76 FR 39850 - Seamless Refined Copper Pipe and Tube From Mexico: Notice of Initiation of Antidumping Duty New...

Science.gov (United States)

2011-07-07

... and Tube From Mexico and the People's Republic of China: Antidumping Duty Orders and Amended Final... copper pipe and tube from Mexico exported by GD, for the period November 22, 2010, through April 30, 2011... and Tube From Mexico: Notice of Initiation of Antidumping Duty New Shipper Review AGENCY: Import...

78 FR 69820 - Seamless Refined Copper Pipe and Tube From the People's Republic of China: Preliminary Results...

Science.gov (United States)

2013-11-21

...\\ \\1\\ See Seamless Refined Copper Pipe and Tube From Mexico and the People's Republic of China... and Tube From the People's Republic of China: Preliminary Results and Partial Rescission of... China (``PRC''), covering the period November 1, 2011 through October 31, 2012. The Department has...

76 FR 33200 - Light-Walled Rectangular Pipe and Tube from Turkey; Notice of Preliminary Results of Antidumping...

Science.gov (United States)

2011-06-08

...) metallic coating; (3) painted/non-painted; (4) perimeter; (5) wall thickness; and (6) shape. See the... pipe and tube from Turkey. Atlas Tube, Inc. and Searing Industries, Inc. are petitioners in this case... through April 2010. Our analysis indicated, based on record evidence, that the appropriate date of sale of...

77 FR 2318 - Certain Circular Welded Pipe and Tube From Brazil, India, Korea, Mexico, Taiwan, Thailand, and...

Science.gov (United States)

2012-01-17

..., Taiwan, Thailand, and Turkey; Scheduling of Full Five-Year Reviews AGENCY: United States International... Turkey, the antidumping duty orders on welded carbon steel pipe and tube from India, Thailand, and Turkey...

Heat pipe and method of production of a heat pipe

International Nuclear Information System (INIS)

Kemp, R.S.

1975-01-01

The heat pipe consists of a copper pipe in which a capillary network or wick of heat-conducting material is arranged in direct contact with the pipe along its whole length. Furthermore, the interior space of the tube contains an evaporable liquid for pipe transfer. If water is used, the capillary network consists of, e.g., a phosphorus band network. To avoid contamination of the interior of the heat pipe during sealing, its ends are closed by mechanical deformation so that an arched or plane surface is obtained which is in direct contact with the network. After evacuation of the interior space, the remaining opening is closed with a tapered pin. The ratio wall thickness/tube diameter is between 0.01 and 0.6. (TK/AK) [de

78 FR 286 - Circular Welded Carbon Steel Pipes and Tubes From Turkey; Amended Final Results of Antidumping...

Science.gov (United States)

2013-01-03

... the scope of this order, except for line pipe, oil country tubular goods, boiler tubing, cold-drawn or... order (``APO'') of their responsibility concerning the disposition of proprietary information disclosed...

The performance of solar collector CPC (compound parabolic concentrator) type with three pipes covered by glass tubes

Science.gov (United States)

Gaos, Yogi Sirodz; Yulianto, Muhamad; Juarsa, Mulya; Nurrohman, Marzuki, Edi; Yuliaji, Dwi; Budiono, Kabul

2017-03-01

Indonesia is a tropical country that has potential energy of solar radiation worth of 4.5 until 4.8 kWh/m2. However, this potential has not been utilized regularly. This paper will discuss the performance of solar collector compound parabolic concentrator (CPC) type with water as the working fluid. This CPC solar collector utilized three pipes covered by glass tubes. This paper has contribution to provide the temperature achievement between three pipes covered by glass tubes with and without glass cover of solar collector CPC type. The research conducted by varying the water flow rate of 1 l/m up to 6 l/m with three pipes arranged in series and parallel. From the results, the used of solar collector CPC type in the current study shows that the decrease of solar radiation, which was caused by climate change, did not influence the heat absorbance by water in the pipe. Therefore, the design of the solar collector in this research has potential to be used in future when solar radiation are used as the energy source.

77 FR 39736 - Certain Circular Welded Pipe and Tube From Brazil, India, Korea, Mexico, Taiwan, Thailand, and...

Science.gov (United States)

2012-07-05

..., Taiwan, Thailand, and Turkey Determinations On the basis of the record \\1\\ developed in the subject five... circular welded pipe and tube from Brazil, India, Korea, Mexico, Taiwan, Thailand, and Turkey would be likely to lead to continuation or recurrence of material injury to an industry in the United States...

Superconducting pipes and levitating magnets.

Science.gov (United States)

Levin, Yan; Rizzato, Felipe B

2006-12-01

Motivated by a beautiful demonstration of the Faraday and the Lenz laws in which a small neodymium magnet falls slowly through a conducting nonferromagnetic tube, we consider the dynamics of a magnet falling coaxially through a superconducting pipe. Unlike the case of normal conducting pipes, in which the magnet quickly reaches the terminal velocity, inside a superconducting tube the magnet falls freely. On the other hand, to enter the pipe the magnet must overcome a large electromagnetic energy barrier. For sufficiently strong magnets, the barrier is so large that the magnet will not be able to penetrate it and will be levitated over the mouth of the pipe. We calculate the work that must done to force the magnet to enter a superconducting tube. The calculations show that superconducting pipes are very efficient at screening magnetic fields. For example, the magnetic field of a dipole at the center of a short pipe of radius a and length L approximately > a decays, in the axial direction, with a characteristic length xi approximately 0.26a. The efficient screening of the magnetic field might be useful for shielding highly sensitive superconducting quantum interference devices. Finally, the motion of the magnet through a superconducting pipe is compared and contrasted to the flow of ions through a trans-membrane channel.

78 FR 35251 - Seamless Refined Copper Pipe and Tube From the People's Republic of China: Final Results and...

Science.gov (United States)

2013-06-12

... of the order, the products covered are all seamless circular refined copper pipes and tubes.\\6\\ The..., 2011). The Department announced a refinement to its assessment practice in non-market economy cases.\\12... for the PRC- wide entity. \\12\\ See Non-Market Economy Antidumping Proceedings: Assessment of...

Thermal performance of evacuated tube heat pipe solar collector

Science.gov (United States)

Putra, Nandy; Kristian, M. R.; David, R.; Haliansyah, K.; Ariantara, Bambang

2016-06-01

The high fossil energy consumption not only causes the scarcity of energy but also raises problems of global warming. Increasing needs of fossil fuel could be reduced through the utilization of solar energy by using solar collectors. Indonesia has the abundant potential for solar energy, but non-renewable energy sources still dominate energy consumption. With heat pipe as passive heat transfer device, evacuated tube solar collector is expected to heat up water for industrial and home usage without external power supply needed to circulate water inside the solar collector. This research was conducted to determine the performance of heat pipe-based evacuated tube solar collector as solar water heater experimentally. The experiments were carried out using stainless steel screen mesh as a wick material, and water and Al2O3-water 0.1% nanofluid as working fluid, and applying inclination angles of 0°, 15°, 30°, and 45°. To analyze the heat absorbed and transferred by the prototype, water at 30°C was circulated through the condenser. A 150 Watt halogen lamp was used as sun simulator, and the prototype was covered by an insulation box to obtain a steady state condition with a minimum affection of ambient changes. Experimental results show that the usage of Al2O3-water 0.1% nanofluid at 30° inclination angle provides the highest thermal performance, which gives efficiency as high as 0.196 and thermal resistance as low as 5.32 °C/W. The use of nanofluid as working fluid enhances thermal performance due to high thermal conductivity of the working fluid. The increase of the inclination angle plays a role in the drainage of the condensate to the evaporator that leads to higher thermal performance until the optimal inclination angle is reached.

76 FR 3612 - Circular Welded Carbon Steel Pipes and Tubes From Taiwan; Extension of Time Limit for Preliminary...

Science.gov (United States)

2011-01-20

... DEPARTMENT OF COMMERCE International Trade Administration [A-583-008] Circular Welded Carbon Steel... Steel Pipes and Tubes From Taiwan: Notice of Partial Rescission of Antidumping Duty Administrative... complete the preliminary results of this review within the original time frame because we require...

Parabolic solar cooker: Cooking with heat pipe vs direct spiral copper tubes

Science.gov (United States)

Craig, Omotoyosi O.; Dobson, Robert T.

2016-05-01

Cooking with solar energy has been seen by many researchers as a solution to the challenges of poverty and hunger in the world. This is no exception in Africa, as solar coking is viewed as an avenue to eliminate the problem of food insecurity, insufficient energy supply for household and industrial cooking. There are several types of solar cookers that have been manufactured and highlighted in literature. The parabolic types of solar cookers are known to reach higher temperatures and therefore cook faster. These cookers are currently being developed for indoor cooking. This technology has however suffered low cooking efficiency and thus leads to underutilization of the high heat energy captured from the sun in the cooking. This has made parabolic solar cookers unable to compete with other conventional types of cookers. Several methods to maximize heat from the sun for indirect cooking has been developed, and the need to improve on them of utmost urgency. This paper investigates how to optimize the heat collected from the concentrating types of cookers by proposing and comparing two types of cooking sections: the spiral hot plate copper tube and the heat pipe plate. The system uses the concentrating solar parabolic dish technology to focus the sun on a conical cavity of copper tubes and the heat is stored inside an insulated tank which acts both as storage and cooking plate. The use of heat pipes to transfer heat between the oil storage and the cooking pot was compared to the use of a direct natural syphon principle which is achieved using copper tubes in spiral form like electric stove. An accurate theoretical analysis for the heat pipe cooker was achieved by solving the boiling and vaporization in the evaporator side and then balancing it with the condensation and liquid-vapour interaction in the condenser part while correct heat transfer, pressure and height balancing was calculated in the second experiment. The results show and compare the cooking time, boiling

Stress corrosion cracking of steam generator tube and primary pipe in PWR type nuclear power plants

International Nuclear Information System (INIS)

Zhang Weiguo; Gao Fengqin; Zhou Hongyi

1992-03-01

The behavior of stress corrosion cracking (SCC) was studied by slow strain rate test (SSRT), constant load test (CLT) and low frequency cyclic loading test (LFCLT). The purpose of these tests is to get the test data for evaluating the integrity of pressurized boundary of pipes in Qinshan and Guangdong nuclear power plants (NPPs). Tested materials are 316 nuclear grade stainless steel (SS) for primary pipes in welded heat affected zone (WHAZ) and tubes of heat transfer, such as Incoloy-800, Inconel-600 and 321 SS which are used for steam generator in PWR NPPs. The effects of material metallurgy, shot peening treatment, tensile load, strain rate, cyclic load and water chemistry on the behavior of SCC were considered

Stress corrosion cracking of steam generator tube and primary pipe in PWR type nuclear power plants

International Nuclear Information System (INIS)

Zhang Weiguo; Gao Fengqin; Zhou Hongyi

1993-01-01

The behavior of stress corrosion cracking (SCC) is studied by slow strain rate test (SSRT), constant load test (CLT) and low frequency cyclic loading test (LFCLT). The purpose of these tests is to get the test data for evaluating the integrity of pressurized boundary of pipes in Qinshan and Guangdong nuclear power plants. Tested materials are 316 nuclear grade stainless steel (SS) for primary pipes in welded heat affected zone (WHAZ) and steam generator tubes, such as Incoloy-800, Inconel-600, Inconel-690 and 321 SS which are used for steam generator in PWR. The effects of material metallurgy, shot-peening treatment, tensile load, strain rate, cyclic load and water chemistry on the behavior of SCC are investigated

46 CFR 182.455 - Fuel piping.

Science.gov (United States)

2010-10-01

... system is of nickel-copper or copper-nickel. When making tube connections, the tubing must be cut square...) MACHINERY INSTALLATION Specific Machinery Requirements § 182.455 Fuel piping. (a) Materials and workmanship. The materials and construction of fuel lines, including pipe, tube, and hose, must comply with the...

PIPE STRESS and VERPIP codes for stress analysis and verifications of PEC reactor piping

International Nuclear Information System (INIS)

Cesari, F.; Ferranti, P.; Gasparrini, M.; Labanti, L.

1975-01-01

To design LMFBR piping systems following ASME Sct. III requirements unusual flexibility computer codes are to be adopted to consider piping and its guard-tube. For this purpose PIPE STRESS code previously prepared by Southern-Service, has been modified. Some subroutine for detailed stress analysis and principal stress calculations on all the sections of piping have been written and fitted in the code. Plotter can also be used. VERPIP code for automatic verifications of piping as class 1 Sct. III prescriptions has been also prepared. The results of PIPE STRESS and VERPIP codes application to PEC piping are in section III of this report

The study on pressure oscillation and heat transfer characteristics of oscillating capillary tube heat pipe

International Nuclear Information System (INIS)

Kim, Jong Soo; Bui, Ngoc Hung; Jung, Hyun Seok; Lee, Wook Hyun

2003-01-01

In the present study, the characteristics of pressure oscillation and heat transfer performance in an oscillating capillary tube heat pipe were experimentally investigated with respect to the heat flux, the charging ratio of working fluid, and the inclination angle to the horizontal orientation. The experimental results showed that the frequency of pressure oscillation was between 0.1 Hz and 1.5 Hz at the charging ratio of 40 vol.%. The saturation pressure of working fluid in the oscillating capillary tube heat pipe increased as the heat flux was increased. Also, as the charging ratio of working fluid was increased, the amplitude of pressure oscillation increased. When the pressure waves were symmetric sinusoidal waves at the charging ratios of 40 vol.% and 60 vol.%, the heat transfer performance was improved. At the charging ratios of 20 vol.% and 80 vol.%, the waveforms of pressure oscillation were more complicated, and the heat transfer performance reduced. At the charging ratio of 40 vol.%, the heat transfer performance of the OCHP was at the best when the inclination angle was 90 .deg., the pressure wave was a sinusoidal waveform, the pressure difference was at the least, the oscillation amplitude was at the least, and the frequency of pressure oscillation was the highest

75 FR 1335 - Circular Welded Carbon Steel Pipes and Tubes from Taiwan; Extension of Time Limit for Preliminary...

Science.gov (United States)

2010-01-11

... DEPARTMENT OF COMMERCE International Trade Administration [A-583-008] Circular Welded Carbon Steel... review of the antidumping duty order on circular welded carbon steel pipes and tubes from Taiwan.\\1\\ On... review within the original time frame because we require additional time to obtain information from the...

Long-term creep rupture strength of weldment of Fe-Ni based alloy as candidate tube and pipe for advanced USC boilers

Energy Technology Data Exchange (ETDEWEB)

Bao, Gang; Sato, Takashi [Babcok-Hitachi K.K., Hiroshima (Japan). Kure Research Laboratory; Marumoto, Yoshihide [Babcok-Hitachi K.K., Hiroshima (Japan). Kure Div.

2010-07-01

A lot of works have been going to develop 700C USC power plant in Europe and Japan. High strength Ni based alloys such as Alloy 617, Alloy 740 and Alloy 263 were the candidates for boiler tube and pipe in Europe, and Fe-Ni based alloy HR6W (45Ni-24Fe-23Cr-7W-Ti) is also a candidate for tube and pipe in Japan. One of the Key issues to achieve 700 C boilers is the welding process of these alloys. Authors investigated the weldability and the long-term creep rupture strength of HR6W tube. The weldments were investigated metallurgically to find proper welding procedure and creep rupture tests are ongoing exceed 38,000 hours. The long-term creep rupture strengths of the HST weld joints are similar to those of parent metals and integrity of the weldments was confirmed based on with other mechanical testing results. (orig.)

Advanced industrial ceramic heat pipe recuperators

Energy Technology Data Exchange (ETDEWEB)

Strumpf, H.J.; Stillwagon, T.L.; Kotchick, D.M.; Coombs, M.G.

1988-01-01

This paper summarizes the results of an investigation involving the use of ceramic heat pipe recuperators for high-temperature heat recovery from industrial furnaces. The function of the recuperator is to preheat combustion air with furnace exhaust gas. The heat pipe recuperator comprises a bundle of individual ceramic heat pipes acting in concert, with a partition separating the air and exhaust gas flow streams. Because each heat pipe is essentially an independent heat exchanger, the failure of a single tube does not compromise recuperator integrity, has only a minimal effect on overall heat exchanger performance and enables easier replacement of individual heat pipes. In addition, the heat pipe acts as an essentially isothermal heat transfer device, leading to a high thermodynamic efficiency. Cost estimates developed for heat pipe recuperator systems indicate favorable payback periods. Laboratory studies have demonstrated the feasibility of fabricating the required ceramic tubes, coating the inside of the tubes with CVD tungsten, and sealing the heat pipe with an electron-beam-welded or vacuum-brazed end cap.

Investigation of mechanical properties of bimetallic square tubes produced by shape rolling of Al/Cu circular pipes

International Nuclear Information System (INIS)

Tajyar, Ali; Masoumi, Abolfazi

2016-01-01

We investigated the effect of shape rolling process on the bond strength and mechanical properties of Al/Cu bimetal pipes. A bimetal circular pipe was fabricated by the explosive welding process. Then, the bimetal explosive-welded circular pipe was reshaped to a square tube by means of the shape rolling process. The mechanical properties of explosive welded pipes and shape-rolled tubes at the various stages of the rolling process were experimentally investigated by using the shear testing, micro hardness testing along the thicknesses and measurement of yield. The obtained results show that with the increase of roll gap reduction during the various stages, the hardness increases, while the shear strength decreases. However, their effects on hardness increase are not the same for both materials. Yield stress measurement results indicate that the average yield stress increases during explosive welding and also shape rolling process, but the rate of increase is more intensive in the explosive welding process. Moreover, the morphology of the interface before and after the Shape rolling was examined by Optical microscope (OM) and the presence of the intermetallic compounds at the interface was investigated by the electron microscope (SEM) and EDS analysis. Examination of the interfaces morphology revealed that, due to the brittle nature of the intermetallic compounds at the joining interface, the nucleation and propagation of micro cracks accelerated during the shape rolling process and the amount of micro cracks increases which makes the shear strength decrease

Investigation of mechanical properties of bimetallic square tubes produced by shape rolling of Al/Cu circular pipes

Energy Technology Data Exchange (ETDEWEB)

Tajyar, Ali; Masoumi, Abolfazi [School of Mechanical Engineering, College of Engineering, University of Tehran, Tehran (Iran, Islamic Republic of)

2016-09-15

We investigated the effect of shape rolling process on the bond strength and mechanical properties of Al/Cu bimetal pipes. A bimetal circular pipe was fabricated by the explosive welding process. Then, the bimetal explosive-welded circular pipe was reshaped to a square tube by means of the shape rolling process. The mechanical properties of explosive welded pipes and shape-rolled tubes at the various stages of the rolling process were experimentally investigated by using the shear testing, micro hardness testing along the thicknesses and measurement of yield. The obtained results show that with the increase of roll gap reduction during the various stages, the hardness increases, while the shear strength decreases. However, their effects on hardness increase are not the same for both materials. Yield stress measurement results indicate that the average yield stress increases during explosive welding and also shape rolling process, but the rate of increase is more intensive in the explosive welding process. Moreover, the morphology of the interface before and after the Shape rolling was examined by Optical microscope (OM) and the presence of the intermetallic compounds at the interface was investigated by the electron microscope (SEM) and EDS analysis. Examination of the interfaces morphology revealed that, due to the brittle nature of the intermetallic compounds at the joining interface, the nucleation and propagation of micro cracks accelerated during the shape rolling process and the amount of micro cracks increases which makes the shear strength decrease.

Water driven turbine/brush pipe cleaner

Science.gov (United States)

Werlink, Rudy J. (Inventor)

1995-01-01

Assemblies are disclosed for cleaning the inside walls of pipes and tubes. A first embodiment includes a small turbine with angled blades axially mounted on one end of a standoff support. An O-ring for stabilizing the assembly within the pipe is mounted in a groove within the outer ring. A replaceable circular brush is fixedly mounted on the opposite end of the standoff support and can be used for cleaning tubes and pipes of various diameters, lengths and configurations. The turbine, standoff support, and brush spin in unison relative to a hub bearing that is fixedly attached to a wire upstream of the assembly. The nonrotating wire is for retaining the assembly in tension and enabling return of the assembly to the pipe entrance. The assembly is initially placed in the pipe or tube to be cleaned. A pressurized water or solution source is provided at a required flow-rate to propel the assembly through the pipe or tube. The upstream water pressure propels and spins the turbine, standoff support and brush. The rotating brush combined with the solution cleans the inside of the pipe. The solution flows out of the other end of the pipe with the brush rotation controlled by the flow-rate. A second embodiment is similar to the first embodiment but instead includes a circular shaped brush with ring backing mounted in the groove of the exterior ring of the turbine, and also reduces the size of the standoff support or eliminates the standoff support.

Fabrication of an improved tube-to-pipe header heat exchanger for the Fuel Failure Mockup (FFM) Facility

International Nuclear Information System (INIS)

Prislinger, J.J.; Jones, R.H.

1977-05-01

The procedure used in fabricating an improved tube-to-pipe header heat exchanger for the Fuel Failure Mockup (FFM) Facility is described. Superior performance is accomplished at reduced cost with adherence to the ASME Boiler and Pressure Vessel Code. The techniques used and the method of fabrication are described in detail

Evaluation of wall thinning profile by flow accelerated corrosion in separation and union pipe

International Nuclear Information System (INIS)

Watanabe, Shun; Yoneda, Kimitoshi

2013-01-01

Flow Accelerated Corrosion (FAC) is a pipe wall thinning phenomena to be monitored and managed in power plants with high priority. At present, its management has been conducted with conservative evaluation of thinning rate and residual lifetime of the piping based on wall thickness measurements. However, noticeable case of wall thinning was occurred at separation and union pipe. In such pipe system, it is a problem to manage section beneath reinforcing plate of T-tube pipe and 'crotch' of T-joint pipe; the region where wall thickness measurement is difficult to conduct with ordinary ultrasonic testing device. In this study, numerical analysis for separation and union part of T-tube and T-joint pipe was conducted, and wall thinning profile by Flow Accelerated Corrosion was evaluated by calculating mass transfer coefficient and geometry factor. Based on these results, we considered applicable wall thinning management for T-tube and T-joint pipe. In the case of union flow from main and branch pipe, the wall thinning profile of T-tube showed the tendency of increase at main pipe like semielliptical region. On the other hand, noticeable profile appeared at 'crotch' in T-joint. Although it was found that geometry factor of T-joint in this case was half the value of T-tube, an alternative evaluation method to previous one might be needed for the profiles of 'semielliptical region' and 'crotch'. (author)

Dual manifold heat pipe evaporator

Science.gov (United States)

Adkins, D.R.; Rawlinson, K.S.

1994-01-04

An improved evaporator section is described for a dual manifold heat pipe. Both the upper and lower manifolds can have surfaces exposed to the heat source which evaporate the working fluid. The tubes in the tube bank between the manifolds have openings in their lower extensions into the lower manifold to provide for the transport of evaporated working fluid from the lower manifold into the tubes and from there on into the upper manifold and on to the condenser portion of the heat pipe. A wick structure lining the inner walls of the evaporator tubes extends into both the upper and lower manifolds. At least some of the tubes also have overflow tubes contained within them to carry condensed working fluid from the upper manifold to pass to the lower without spilling down the inside walls of the tubes. 1 figure.

Pressure tube reactor

International Nuclear Information System (INIS)

Seki, Osamu; Kumasaka, Katsuyuki.

1988-01-01

Purpose: To remove the heat of reactor core using a great amount of moderators at the periphery of the reactor core as coolants. Constitution: Heat of a reactor core is removed by disposing a spontaneous recycling cooling device for cooling moderators in a moderator tank, without using additional power driven equipments. That is, a spontaneous recycling cooling device for cooling the moderators in the moderator tank is disposed. Further, the gap between the inner wall of a pressure tube guide pipe disposed through the vertical direction of a moderator tank and the outer wall of a pressure tube inserted through the guide pipe is made smaller than the rupture distortion caused by the thermal expansion upon overheating of the pressure tube and greater than the minimum gap required for heat shiels between the pressure tube and the pressure tube guide pipe during usual operation. In this way, even if such an accident as can not using a coolant cooling device comprising power driven equipment should occur in the pressure tube type reactor, the rise in the temperature of the reactor core can be retarded to obtain a margin with time. (Kamimura, M.)

Finned Carbon-Carbon Heat Pipe with Potassium Working Fluid

Science.gov (United States)

Juhasz, Albert J.

2010-01-01

This elemental space radiator heat pipe is designed to operate in the 700 to 875 K temperature range. It consists of a C-C (carbon-carbon) shell made from poly-acrylonitride fibers that are woven in an angle interlock pattern and densified with pitch at high process temperature with integrally woven fins. The fins are 2.5 cm long and 1 mm thick, and provide an extended radiating surface at the colder condenser section of the heat pipe. The weave pattern features a continuous fiber bath from the inner tube surface to the outside edges of the fins to maximize the thermal conductance, and to thus minimize the temperature drop at the condenser end. The heat pipe and radiator element together are less than one-third the mass of conventional heat pipes of the same heat rejection surface area. To prevent the molten potassium working fluid from eroding the C C heat pipe wall, the shell is lined with a thin-walled, metallic tube liner (Nb-1 wt.% Zr), which is an integral part of a hermetic metal subassembly which is furnace-brazed to the inner surface of the C-C tube. The hermetic metal liner subassembly includes end caps and fill tubes fabricated from the same Nb-1Zr alloy. A combination of laser and electron beam methods is used to weld the end caps and fill tubes. A tungsten/inert gas weld seals the fill tubes after cleaning and charging the heat pipes with potassium. The external section of this liner, which was formed by a "Uniscan" rolling process, transitions to a larger wall thickness. This section, which protrudes beyond the C-C shell, constitutes the "evaporator" part of the heat pipe, while the section inside the shell constitutes the condenser of the heat pipe (see figure).

Design of a cavity heat pipe receiver experiment

Science.gov (United States)

Schneider, Michael G.; Brege, Mark H.; Greenlee, William J.

1992-01-01

A cavity heat pipe experiment has been designed to test the critical issues involved with incorporating thermal energy storage canisters into a heat pipe. The experiment is a replication of the operation of a heat receiver for a Brayton solar dynamic power cycle. The heat receiver is composed of a cylindrical receptor surface and an annular heat pipe with thermal energy storage canisters and gaseous working fluid heat exchanger tubes surrounding it. Hardware for the cavity heat pipe experiment will consist of a sector of the heat pipe, complete with gas tube and thermal energy storage canisters. Thermal cycling tests will be performed on the heat pipe sector to simulate the normal energy charge/discharge cycle of the receiver in a spacecraft application.

Method of fabricating a poision tube for reactor control rods

Energy Technology Data Exchange (ETDEWEB)

Mori, Yasuhiko; Yoshida, Toshimi; Masaoka, Isao; Naruse, Akisuke

1983-04-28

A method to unify the neutron absorbing performance, enhance the workability in the insertion of neutron absorber tube and further decrease the stresses acting on the neutron absorber coating tube is described. The neutron absorber coated rod comprising neutron absorbing substance and a metal pipe is fabricated by compressing a metal pipe filled with the neutron absorber. Specifically, neutron absorbing substance such as boron carbide powder or the like is filled in a metal pipe such as made of stainless steel tube by way of vibration packing or the like. Then, after heating the metal pipe, it is applied with compression working such as swaging into a fine tube to increase the packing density of the absorbing substance filled in the pipe to greater than 60% of the theoretical density and completely contacted closely to the inner wall of the pipe. The neutron absorber coated rod thus fabricated can be inserted to an external coating tube with ease at a predetermined gap.

Design and manufacture of ceramic heat pipes for high temperature applications

International Nuclear Information System (INIS)

Meisel, Peter; Jobst, Matthias; Lippmann, Wolfgang; Hurtado, Antonio

2015-01-01

Heat exchangers based on ceramic heat pipes were designed for use under highly abrasive and corrosive atmospheres at temperatures in the range of 800–1200 °C for high-temperature power-engineering applications. The presented heat pipes are gravity assisted and based on a multi-layer concept comprising a ceramic cladding and an inner metal tube that contains sodium as the working fluid. Hermetical encapsulation of the working fluid was achieved by electron-beam welding of the inner metal tube. Subsequently, closure of the surrounding ceramic tube was performed by laser brazing technology using a glass solder. Temperature resistance and functionality of the manufactured ceramic thermosyphons could be confirmed experimentally in a hot combustion gas atmosphere at temperatures up to 1100 °C. The ceramic tubes used had an outer diameter of 22 mm and a total length of 770 mm. The measured axial heat transfer of the ceramic gravity assisted heat pipes at the stationary operating point with cold/hot gas temperature of 100 °C/900 °C was 400 W. The result of the calculation using the created mathematical model amounted to 459 W. - Highlights: • Heat-pipe design consists of a ceramic shell and an inner metallic tube. • Laser brazing technology is suitable to seal ceramic heat-pipes. • Thermal characteristic of double wall thermosyphon was modelled using FEM code. • Experimental investigations demonstrated functionality of double wall thermosyphons

Modelling of fiberglass pipe destruction process

Directory of Open Access Journals (Sweden)

А. К. Николаев

2017-03-01

Full Text Available The article deals with important current issue of oil and gas industry of using tubes made of high-strength composite corrosion resistant materials. In order to improve operational safety of industrial pipes it is feasible to use composite fiberglass tubes. More than half of the accidents at oil and gas sites happen at oil gathering systems due to high corrosiveness of pumped fluid. To reduce number of accidents and improve environmental protection we need to solve the issue of industrial pipes durability. This problem could be solved by using composite materials from fiberglass, which have required physical and mechanical properties for oil pipes. The durability and strength can be monitored by a fiberglass winding method, number of layers in composite material and high corrosion-resistance properties of fiberglass. Usage of high-strength composite materials in oil production is economically feasible; fiberglass pipes production is cheaper than steel pipes. Fiberglass has small volume weight, which simplifies pipe transportation and installation. In order to identify the efficiency of using high-strength composite materials at oil production sites we conducted a research of their physical-mechanical properties and modelled fiber pipe destruction process.

Experimental studies of PWR primary piping under loca

International Nuclear Information System (INIS)

Caumette, Pierre; Garcia, J.L.

1980-07-01

The experimental program performed on AQUITAINE II facility is directed to study the mechanical behavior of primary PWR pipes and the forces exerted on the neighbouring structures as a consequence of a breach opening. It has been developed in the form of a quadripartite agreement between the Commissariat a l'Energie Atomique, Framatome, Electricite de France and Westinghouse. Some forty tests have been carried out with different pipe configurations (straight tube, elbow, S- or U-shaped tube) and different break types (single or double guillotine). The following aspects are investigated: - the dynamic behavior of the pipe and in particular the formation of a plastic hinge at the restraint; - the impact function of a pipe or an energy-absorbing bumper; - the lateral stability of both ends of a pipe, after a double-guillotine break [fr

Apparatus for measuring total flow in pipes

International Nuclear Information System (INIS)

Matthews, H.

1986-01-01

To obtain a sample representative of the total flow in a pipe over a given period a Pitot tube is located in the pipe and connected to a collector outside the pipe. The collector is pressurised to a pressure substantially equal to the static head of the flow in the pipe via a line. Liquid is discharged from a collector to a container which is vented to atmosphere. (author)

Magnet fall inside a conductive pipe: motion and the role of the pipe wall thickness

Energy Technology Data Exchange (ETDEWEB)

Donoso, G; Ladera, C L; Martin, P [Departamento de Fisica, Universidad Simon BolIvar, Apdo. 89000, Caracas 1080 (Venezuela, Bolivarian Republic of)], E-mail: clladera@usb.ve, E-mail: pmartin@usb.ve

2009-07-15

Theoretical models and experimental results are presented for the retarded fall of a strong magnet inside a vertical conductive non-magnetic tube. Predictions and experimental results are in good agreement modelling the magnet as a simple magnetic dipole. The effect of varying the pipe wall thickness on the retarding magnetic drag is studied for pipes of different materials. Conductive pipes of thinner walls produce less dragging force and the retarded fall of the magnet is seen to consist of an initial transient accelerated regime followed by a stage of uniform motion. Alternative models of the magnet field are also presented that improve the agreement between theory and experiments.

76 FR 50173 - Drill Pipe From the People's Republic of China: Initiation of Anti-circumvention Inquiry

Science.gov (United States)

2011-08-12

... facility exports PRC-produced pipe and tool joints to AlMansoori/Hilong in the UAE, which friction welds... Emirates (the ``UAE''). \\3\\ ``Pipe'' is heat treated and upset green tube, minus the tool joint. See... collars (including all drill collar green tubes) and unfinished drill pipe (including drill pipe green...

Experimental analytical study on heat pipes

International Nuclear Information System (INIS)

Ismail, K.A.R.; Liu, C.Y.; Murcia, N.

1981-01-01

An analytical model is developed for optimizing the thickness distribution of the porous material in heat pipes. The method was used to calculate, design and construct heat pipes with internal geometrical changes. Ordinary pipes are also constructed and tested together with the modified ones. The results showed that modified tubes are superior in performance and that the analytical model can predict their performance to within 1.5% precision. (Author) [pt

Multiple-effect diffusion solar still coupled with a vacuum-tube collector and heat pipe

KAUST Repository

Chong, Tze-Ling

2014-08-01

The present study develops a multiple-effect diffusion solar still (MEDS) with a bended-plate design in multiple-effect diffusion unit (MDU) to solve the peel-off problem of wick material. The MDU is coupled with a vacuum-tube solar collector to produce a high temperature gradient for high productivity. A heat pipe is used to transfer the solar heat to the MDU. A prototype MEDS-1L was built and tested outdoors. Four performance indexes are proposed for the performance evaluation of MEDS, including daily pure water production per unit area of glass cover, solar absorber, and evaporating surface (Mcov, Msol, Mevp, respectively), and solar distillation efficiency Rcov. The outdoor test results of MEDS-1L show that the solar collector supply temperature Th reaches 100°C at solar radiation 800Wm-2. The highest Mcov is 23.9kgm-2d-1 which is about 29% higher than the basin-type MEDS [11]. The highest value is 25.9kgm-2d-1 for Msol and 2.79kgm-2d-1 for Mevp. The measured Rcov is 1.5-2.44, higher than the basin-type MEDS (1.45-1.88). The Mcov, Msol, Mevp and Rcov of MEDS-1L are all higher than the theoretical calculation of a MEDS with a flat-plate solar collector coupled with a heat pipe (MEDS-FHP) [17].© 2014 Elsevier B.V.

An in-pipe mobile micromachine using fluid power. A mechanism adaptable to pipe diameters

International Nuclear Information System (INIS)

Yoshida, Kazuhiro; Yokota, Shinichi; Takahashi, Ken

2000-01-01

To realize micro maintenance robots for small diameter pipes of nuclear reactors and so on, high power in-pipe mobile micromachines have been required. The authors have proposed the bellows microactuator using fluid power and have tried to apply the actuators to in-pipe mobile micromachines. In the previous papers, some inchworm mobile machine prototypes with 25 mm in diameter are fabricated and the traveling performances are experimentally investigated. In this paper, to miniaturize the in-pipe mobile machine and to make it adaptable to pipe diameters, firstly, a simple rubber-tube actuator constrained with a coil-spring is proposed and the static characteristics are investigated. Secondly, a supporting mechanism which utilizes a toggle mechanism and is adaptable to pipe diameters is proposed and the supporting forces are investigated. Finally, an in-pipe mobile micromachine for pipe with 4 - 5 mm in diameter is fabricated and the maximum traveling velocity of 7 mm/s in both ahead and astern movements is experimentally verified. (author)

Performance analysis of a solar still coupled with evacuated heat pipes

Science.gov (United States)

Pramod, B. V. N.; Prudhvi Raj, J.; Krishnan, S. S. Hari; Kotebavi, Vinod

2018-02-01

In developing countries the need for better quality drinking water is increasing steadily. We can overcome this need by using solar energy for desalination purpose. This process includes fabrication and analysis of a pyramid type solar still coupled with evacuated heat pipes. This experiment using evacuated heat pipes are carried in mainly three modes namely 1) Still alone 2) Using heat pipe with evacuated tubes 3)Using evacuated heat pipe. For this work single basin pyramid type solar still with 1m2 basin area is fabricated. Black stones and Black paint are utilised in solar still to increase evaporation rate of water in basin. The heat pipe’s evaporator section is placed inside evacuated tube and the heat pipe’s condenser section is connected directly to the pyramid type solar still’s lower portion. The output of distillate water from still with evacuated heat pipe is found to be 40% more than the still using only evacuated tubes.

Simplified pipe gun

International Nuclear Information System (INIS)

Sorensen, H.; Nordskov, A.; Sass, B.; Visler, T.

1987-01-01

A simplified version of a deuterium pellet gun based on the pipe gun principle is described. The pipe gun is made from a continuous tube of stainless steel and gas is fed in from the muzzle end only. It is indicated that the pellet length is determined by the temperature gradient along the barrel right outside the freezing cell. Velocities of around 1000 m/s with a scatter of +- 2% are obtained with a propellant gas pressure of 40 bar

New developments of belt conveyor systems; Inclined belt systems, vertical pipe elevators, vibration belts, oscillating tubes

Energy Technology Data Exchange (ETDEWEB)

Bahke, E.A. (Universitaet Karlsruhe, Karlsruhe (Germany, F.R.). Inst. fuer Foerdertechnik)

1991-03-01

Factors that have influenced the design of belt conveyor systems are discussed - these include strength and shaping. Belt conveyor systems for inclined, steep-angle and vertical conveying are described and comparison made between cable belt and steel cord belt conveyors used in coal mines. Hose-belt or tube conveyors such as are used in the PWH/Conti-Rollgurt Conveyor System for feeding boilers in German coal fired power stations are mentioned and advantages of the pipe-belt conveyor for vertical transport discussed. Design of the vibratory conveyor for transporting solids upwards by pulses is described. 29 refs., 19 figs., 2 tabs.

Duplex-tube sodium-indication steam generator

International Nuclear Information System (INIS)

Matal, O.; Martoch, J.

1984-01-01

The steam generator with duplex tubes and sodium indication is connected to the main sodium input and output via the inlet and outlet chambers and has indication spaces connected to the interspaces of the duplex tubes. The first indication space is linked with the auxiliary inlet pipe to the inlet chamber and the second indication space is connected with the auxiliary pipe to the outlet chamber. Mounted to the auxiliary inlet pipe is at least one closure, i.e., a valve or electromagnetic stop. Mounted on the auxiliary outlet pipe is an indication sensor, e.g., a sodium flow sensor. At least one indication space is provided with an alarm sensor, e.g., a thermocouple, a pressure gauge and one sensor to monitor the hydrogen content of sodium. (J.P.)

Heat Pipe with Axial Wick

Science.gov (United States)

Ambrose, Jay H. (Inventor); Holmes, Rolland (Inventor)

2016-01-01

A heat pipe has an evaporator portion, a condenser portion, and at least one flexible portion that is sealingly coupled between the evaporator portion and the condenser portion. The flexible portion has a flexible tube and a flexible separator plate held in place within the flexible tube so as to divide the flexible tube into a gas-phase passage and a liquid-phase artery. The separator plate and flexible tube are configured such that the flexible portion is flexible in a plane that is perpendicular to the separator plate.

77 FR 10722 - Drill Pipe From the People's Republic of China: Termination of Anti-Circumvention Inquiry

Science.gov (United States)

2012-02-23

... treated and upset green tube, minus the tool joint. See the Petitioners' request at 3. \\5\\ Specifically... joints to Almansoori/Hilong in the UAE, which friction welds the pipe to the tools joints, and then... collars (including all drill collar green tubes) and unfinished drill pipe (including drill pipe green...

Pipe inspection using the pipe crawler. Innovative technology summary report

International Nuclear Information System (INIS)

1999-05-01

The US Department of Energy (DOE) continually seeks safer and more cost-effective remediation technologies for use in the decontamination and decommissioning (D and D) of nuclear facilities. In several of the buildings at the Fernald Site, there is piping that was used to transport process materials. As the demolition of these buildings occur, disposal of this piping has become a costly issue. Currently, all process piping is cut into ten-foot or less sections, the ends of the piping are wrapped and taped to prevent the release of any potential contaminants into the air, and the piping is placed in roll off boxes for eventual repackaging and shipment to the Nevada Test Site (NTS) for disposal. Alternatives that allow for the onsite disposal of process piping are greatly desired due to the potential for dramatic savings in current offsite disposal costs. No means is currently employed to allow for the adequate inspection of the interior of piping, and consequently, process piping has been assumed to be internally contaminated and thus routinely disposed of at NTS. The BTX-II system incorporates a high-resolution micro color camera with lightheads, cabling, a monitor, and a video recorder. The complete probe is capable of inspecting pipes with an internal diameter (ID) as small as 1.4 inches. By using readily interchangeable lightheads, the same system is capable of inspecting piping up to 24 inches in ID. The original development of the BTX system was for inspection of boiler tubes and small diameter pipes for build-up, pitting, and corrosion. However, the system is well suited for inspecting the interior of most types of piping and other small, confined areas. The report describes the technology, its performance, uses, cost, regulatory and policy issues, and lessons learned

Pipe inspection using the pipe crawler. Innovative technology summary report

Energy Technology Data Exchange (ETDEWEB)

NONE

1999-05-01

The US Department of Energy (DOE) continually seeks safer and more cost-effective remediation technologies for use in the decontamination and decommissioning (D and D) of nuclear facilities. In several of the buildings at the Fernald Site, there is piping that was used to transport process materials. As the demolition of these buildings occur, disposal of this piping has become a costly issue. Currently, all process piping is cut into ten-foot or less sections, the ends of the piping are wrapped and taped to prevent the release of any potential contaminants into the air, and the piping is placed in roll off boxes for eventual repackaging and shipment to the Nevada Test Site (NTS) for disposal. Alternatives that allow for the onsite disposal of process piping are greatly desired due to the potential for dramatic savings in current offsite disposal costs. No means is currently employed to allow for the adequate inspection of the interior of piping, and consequently, process piping has been assumed to be internally contaminated and thus routinely disposed of at NTS. The BTX-II system incorporates a high-resolution micro color camera with lightheads, cabling, a monitor, and a video recorder. The complete probe is capable of inspecting pipes with an internal diameter (ID) as small as 1.4 inches. By using readily interchangeable lightheads, the same system is capable of inspecting piping up to 24 inches in ID. The original development of the BTX system was for inspection of boiler tubes and small diameter pipes for build-up, pitting, and corrosion. However, the system is well suited for inspecting the interior of most types of piping and other small, confined areas. The report describes the technology, its performance, uses, cost, regulatory and policy issues, and lessons learned.

Lateral impact on pressurized glass/epoxy pipes

Energy Technology Data Exchange (ETDEWEB)

Santiago, Rafael C.; Alves, Marcilio [Universidade de Sao Paulo (USP), SP (Brazil). Escola Politecnica], e-mail: rafael.santiago@poli.usp.br, e-mail: maralves@usp.br

2009-07-01

This work studies the impact of a drop mass against glass/epoxy composite pipes. The experimental tests comprises an impact hammer and the set-up is such that a drop mass falls transversally to the main length of the tube. The impact response is measured with a non-contact laser system and reveals some issues explored here in a numerical model. Inner pressure was applied to the tube in order to access its influence on failure. It has been found that the numerical model represents well the structural collapse of a pressurized pipe under a lateral impact. (author)

Installation of groundwater observation tubes OL-PVP30-35 at Olkiluoto in Eurajoki 2009

International Nuclear Information System (INIS)

Toropainen, V.

2009-10-01

In order to widen the Posivas groundwater monitoring network at Olkiluoto, Suomen Malmi Oy (Smoy) to install eight new groundwater observation tubes. The identification numbers of the groundwater observation tubes are OL-PVP30, OL-PVP31A and 31B, OL-PVP32, OL-PVP33, OL-PVP34A and 34B and OL-PVP35. The observation tubes were installed between January 28th and February 17th in 2009. The drilling rig used in the installation work was a GM-200 rig. Drilling equipment consisted of casing tubes (n 90/77 mm) with drilling bit, 55 mm geo rods and 64 mm drilling bits. Monitoring pipes (PVC, n 60/52 mm) were lowered into the holes inside the casings. The monitoring pipes consist of a lower section of riser pipe, a middle section of screen pipe and an upper section of riser pipe. The screen pipe slot size is 0.3 mm and the length of the screen section is one or two metres. Protective stainless steel covers with lock-up caps were installed around the monitoring tubes. In addition to the installation of the tubes, the work included observation of soil/drill cuttings quality during drilling, time-penetration measurements and water level measurements after installation. (orig.)

Analysis of cantilever pipes in transverse fluid flow with motion limiting stopper at the free end

International Nuclear Information System (INIS)

Jiyavan, R.

1983-01-01

Flow-induced vibration in heat exchanger tubes can result in impact with the baffle plates and subsequent tube failure through fatigue, fracture and fretting wear. As a step towards the correlation between the random flow excitations and the rate of wear, this paper presents a general theory for predicting the tube motion and the tube baffle impact forces through a case of cantilever pipe with motion limiting stopper at the free end and simultaneously subjected to transverse fluid flow. The mathematical model has been developed using the theory of fluid-structure interactions with model superposition technique. The pipe displacement induced by lift forces is evaluated by numerical integration. When displacement increases to greater than the pipe-stopper clearance, the pipe impacts on stopper. Assuming semielastic impact, the equation of pipe motion during impact is developed using extended Hertz's theory to include the vibration of one of the colliding bodies. The stopper is assumed to be at rest before and after the impact. The constraint imposed on pipe motion, at the free end due to impact of the pipe on stopper, is considered as one of the boundary conditions and is used to evaluate the pipe natural frequencies. The nonlinear equations are solved numerically. The response of the pipe due to wake induced lift forces superposed by the impact response is evaluated. (orig./GL)

Minimization of the negative influence on the biosphere in heavy oil extraction and ecologically clean technology for the injection of the steam with supercritical parameters in oil strata on the basis of new ecologically clean tubing pipes with heat-resistant coatings

Science.gov (United States)

Komkov, M. A.; Moiseev, V. A.; Tarasov, V. A.; Timofeev, M. P.

2015-12-01

Some ecological problems related to heavy-oil extraction and ways for minimizing the negative impacts of this process on the biosphere are discussed. The ecological hazard of, for example, frequently used multistage hydraulic fracturing of formation is noted and the advantages and perspectives of superheated steam injection are considered. Steam generators of a new type and ecologically clean and costeffective insulating for tubing pipes (TPs) are necessary to develop the superheated steam injection method. The article is devoted to solving one of the most important and urgent tasks, i.e., the development and usage of lightweight, nonflammable, environmentally safe, and cost-effective insulating materials. It is shown that, for tubing shielding operating at temperatures up to 420°C, the most effective thermal insulation is a highly porous material based on basalt fiber. The process of filtration deposition of short basalt fibers with a bunch of alumina thermal insulation tubing pipe coatings in the form of cylinders and cylindrical shells from liquid pulp is substantiated. Based on the thermophysical characteristics of basalt fibers and on the technological features of manufacturing highly porous coating insulation, the thickness of a tubing pipe is determined. During the prolonged pumping of the air at an operating temperature of 400°C in the model sample of tubing pipes with insulation and a protective layer, we find that the surface temperature of the thermal barrier coating does not exceed 60°C. Introducing the described technology will considerably reduce the negative impact of heavy-oil extraction on the biosphere.

Study of the performances of acoustic emission testing for glass fibre reinforced plastic pipes containing defects; Etude des performances du controle par emission acoustique de tubes en materiaux composites resine-fibre de verre contenant des defauts

Energy Technology Data Exchange (ETDEWEB)

Villard, D.; Vidal, M.C.

1995-08-01

Glass fibre reinforced plastic pipes are more and more often used, in nuclear power plants, for building or replacement of water pipings classified `nuclear safety`. Tests have been performed to evaluate the performances of acoustic emission testing for in service inspection of these components. The tests were focused on glass fibre reinforced polyester and vinyl-ester pipes, in as received conditions or containing impacts, and intentionally introduced defects. They have been carried out by CETIM, following the ASTM Standard E 1118 (code CARP), to a maximum pressure lever of 25 Bar The results show that the CARP procedure can be used for detection of defects and evaluation of their noxiousness towards internal pressure: most of the tubes containing low energy impacts could not be distinguished from tubes without defect; on the other hand the important noxiousness of lacks of impregnation of roving layer appeared clearly. Complementary tests have been performed on some tubes at a more important pressure lever, for which the damage of the tubes in enough to deteriorate there elastic properties. The results showed that CARP procedure give valuable informations on damage level. It would be interesting to evaluate acoustic emission on tubes containing realistic in-service degradations. (author). 11 refs., 15 figs., 6 tabs., 2 appends.

Tracking chamber made of 15-mm mylar drift tubes

Science.gov (United States)

Kozhin, A.; Borisov, A.; Bozhko, N.; Fakhrutdinov, R.; Plotnikov, I.

2017-05-01

We are presenting a drift chamber composed from three layers of mylar drift tubes with outer diameter 15 mm. The pipe is made of strip of mylar film 125 micrometers thick covered with aluminium from the both sides. A strip of mylar is wrapped around the mandrel. Pipe is created by ultrasonic welding. A single drift tube is self-supported structure withstanding 350 g wire tension without supports and internal overpressure. About 400 such tubes were assembled. Design, quality control procedures of the drift tubes are described. Seven chambers were glued from these tubes of 560 mm length. Each chamber consists of 3 layers, 16 tubes per layer. Several chambers were tested with cosmic rays. Results of the tests, counting rate plateau and coordinate resolution are presented.

Tracking chamber made of 15-mm mylar drift tubes

International Nuclear Information System (INIS)

Kozhin, A.; Borisov, A.; Bozhko, N.; Fakhrutdinov, R.; Plotnikov, I.

2017-01-01

We are presenting a drift chamber composed from three layers of mylar drift tubes with outer diameter 15 mm. The pipe is made of strip of mylar film 125 micrometers thick covered with aluminium from the both sides. A strip of mylar is wrapped around the mandrel. Pipe is created by ultrasonic welding. A single drift tube is self-supported structure withstanding 350 g wire tension without supports and internal overpressure. About 400 such tubes were assembled. Design, quality control procedures of the drift tubes are described. Seven chambers were glued from these tubes of 560 mm length. Each chamber consists of 3 layers, 16 tubes per layer. Several chambers were tested with cosmic rays. Results of the tests, counting rate plateau and coordinate resolution are presented.

49 CFR Appendix B to Part 192 - Qualification of Pipe

Science.gov (United States)

2010-10-01

..., “Standard Specification for Carbon and Alloy Steel Pipe, Electric-Fusion-Welded for High Pressure Service at... by reference, see § 192.7). ASTM D2517—Thermosetting plastic pipe and tubing, “Standard Specification...

Self-assembling segmented coiled tubing

Science.gov (United States)

Raymond, David W.

2016-09-27

Self-assembling segmented coiled tubing is a concept that allows the strength of thick-wall rigid pipe, and the flexibility of thin-wall tubing, to be realized in a single design. The primary use is for a drillstring tubular, but it has potential for other applications requiring transmission of mechanical loads (forces and torques) through an initially coiled tubular. The concept uses a spring-loaded spherical `ball-and-socket` type joint to interconnect two or more short, rigid segments of pipe. Use of an optional snap ring allows the joint to be permanently made, in a `self-assembling` manner.

Enhancement of heat transfer rate with structural modification of double pipe heat exchanger by changing cylindrical form of tubes into conical form

International Nuclear Information System (INIS)

Hashemian, Mehran; Jafarmadar, Samad; Nasiri, Javid; Sadighi Dizaji, Hamed

2017-01-01

Highlights: • An improved geometry is presented by changing tubes form into conical. • Enhancement of heat transfer rate is investigated. • Frictional characteristics for novel geometry are studied. • For a proper understanding of the subject, the exact physical interpretation is added. • The effect of flow, geometry and thermodynamic parameters is considered. - Abstract: In this paper, cylindrical tubes of a double pipe heat exchanger were changed into the conical tubes as an innovative design which causes improvement of thermal performance of heat exchanger without increment of its weight. Utilization of conical tube instead of cylindrical tube can impress both thermal and frictional characteristics of heat exchanger. Hence, the effect of conical tubes on Nusselt number, friction factor and thermal performance factor are evaluated in present research which was not covered already. Moreover, the effects of hydrodynamic, thermodynamic and geometrical characteristics are analyzed. All said parameters are numerically investigated for nine different combinations of flow direction and conical tubes geometry. The results of simulations of the said configurations are presented to compare the cases from different points of view and determine the most thermally efficient case. The results reveal modified geometry makes 63% increment in Nu number and 54% increment in heat transfer rate at optimum condition.

Void fraction in steam-water mixture downward motion in tubes and intertubular spaces

International Nuclear Information System (INIS)

Miropol'skij, Z.L.; Shneerova, R.I.; Karamysheva, A.I.

1978-01-01

Experiments have been carried out with a view to determining the averaged cross-section virtual steam contents for downward steam-air mixture flows in a pipe (diameter 40 mm, length 600 mm) and in a 400 mm-long cylindrical channel, which accomodated 19 cylindrical tubes. Equivalent channel diameter was 9.2 mm. The tests were carried out both under adiabatic flow conditions and in the presence of heat transfer through pipes, which were electrically heated. The p pressure was 3 mPa, specific heat fluxes g=0-0.27 MW/m 2 , mass rates wsub(p)=110-395 kg/m 2 xs in the tube bunch and 95-345 kg/m 2 xs in the pipe. The test results indicate that: the virtual volumetric steam contents in a downward flow of a steam-air mixture are higher than those in an upward flow; x in a tube bunch is substantially smaller than that in a pipe

Theoretical and experimental investigation of the performance of solar thermosyphon heat pipe

International Nuclear Information System (INIS)

Hamidi, A.A.; Khalji Asadi, M.; Yousefi, L.; Moeini, G.

2001-01-01

Thermosyphon is a kind of heat pipe consisting of a tube which after through degassing has been filled with the required working fluid under vacuum, the pipe is equipped with wide fines on both sides in order to absorb solar radiation effectively. In order to eliminate conduction and convection heat transfer phenomena the tube is situated inside an evacuated glass bulb. In order to increase the efficiency and improve the design and working conditions of various types of heat pipes, a fundamental knowledge of the variation of operating parameters inside the heat pipes is necessary. In this paper, effective operating parameters of a thermosyphon heat pipe in uniform and steady condition are studied. These parameters include saturation temperature of the fluid inside the pipe, the variation of liquid and vapor flow rates inside the pipe and finally the pressure drop of liquid and vapor along the length of the pipe. The modeling is first started by writing an energy balance for the control volume of the pipe so that a first approximation for the above mentioned parameters is obtained. In this balance, depending on the type of fluid next to the condenser section and the type of heat transfer phenomena (free or forced convection) and also with due regards to the experimental correlations available, first the Nusselt number and then the heat transfer coefficient is calculated. From the latter, a first estimate of the required values for the liquid and vapor flow rates are found to be 0.222 and 0.0001126 Kg/s, respectively. The thickness of the film was determined to be 0.2 mm. In order to calculate the variations of the above mentioned parameters along the length of the tube, mass heat and momentum balances were written in next step for the control volumes on the liquid film, vapor phase and the system as a whole. Diagrams of these variations were obtained. The results were compared with both the data available in the literature and the experimental findings of a heat

Multi-objective shape optimization of double pipe heat exchanger with inner corrugated tube using RSM method

International Nuclear Information System (INIS)

Han, Huai-Zhi; Li, Bing-Xi; Wu, Hao; Shao, Wei

2015-01-01

Integrated a fully developing three-dimensional heat transfer and flow model, a multi-objective optimization aims to fulfill the geometric design for double-tube heat exchangers with inner corrugated tube is investigated in this work with RSM. Dimensionless corrugation pitch (p/D), dimensionless corrugation height (H/D), dimensionless corrugation radius (r/D) and Reynolds number (Re) are considered as four design parameters. Considering the process parameters, the characteristic numbers involving heat transfer characteristic, resistance characteristic and overall heat transfer performance calculated by CFD, and are served as objective functions to the RSM (Nu c , f c , Nu c /Nu s , f c /f s and h in this paper). The results of optimal designs are a set of multiple optimum solutions, called 'Pareto optimal solutions'. It reveals the identical tendency of Nu c /Nu s and f c /f s reflecting the conflict between them that means augmenting the heat transfer performance with various design parameters in the optimal situation inevitably sacrificed the increase of flow resistance. According to the Pareto optimal curves, the optimum designing parameters of double pipe heat exchanger with inner corrugated tube under the constrains of Nu c /Nu s ≥1.2 are found to be P/D = 0.82, H/D = 0.22, r/D = 0.23, Re = 26,263, corresponding to the maximum value of η = 1.12. (authors)

Magnet Fall inside a Conductive Pipe: Motion and the Role of the Pipe Wall Thickness

Science.gov (United States)

Donoso, G.; Ladera, C. L.; Martin, P.

2009-01-01

Theoretical models and experimental results are presented for the retarded fall of a strong magnet inside a vertical conductive non-magnetic tube. Predictions and experimental results are in good agreement modelling the magnet as a simple magnetic dipole. The effect of varying the pipe wall thickness on the retarding magnetic drag is studied for…

Thermal performance and pressure drop of spiral-tube ground heat exchangers for ground-source heat pump

International Nuclear Information System (INIS)

Jalaluddin; Miyara, Akio

2015-01-01

Thermal performance and pressure drop of the spiral-tube GHE were evaluated in this present work. A numerical simulation tool was used to carry out this research. The heat exchange rates per meter borehole depth of the spiral-tube GHE with various pitches and their pressure drops were compared with that of the U-tube GHE. Furthermore, a comparative analysis between a spiral pipe and straight pipe was performed. In comparison with the straight pipe, using the spiral pipe in the borehole increased the heat exchange rate to the ground per meter borehole depth. However, the pressure drop of water flow also increased due to increasing the length of pipe per meter borehole depth and its spiral geometry. The accuracy of the numerical model was verified for its pressure drop with some pressure drop correlations. The heat exchange rate and pressure drop of the GHEs are presented. As an example, the heat exchange rate per meter borehole depth of spiral pipe with 0.05 m pitch in the turbulent flow increased of 1.5 times. Its pressure drop also increased of 6 times. However, from the view point of energy efficiency, using the spiral pipe in the ground-source heat pump system gives a better performance than using the straight pipe. The heat exchange rate and pressure drop are important parameter in design of the ground-source heat pump (GSHP) system. - Highlights: • Thermal performance and pressure drop of spiral-tube GHE are presented. • Effects of spiral pitch on thermal performance and pressure drop are analyzed. • Using a spiral pipe increases heat exchange rate per meter borehole depth of GHE. • Pressure drop per meter borehole depth also increases in the spiral pipe.

High-performance heat pipes for heat recovery applications

Science.gov (United States)

Saaski, E. W.; Hartl, J. H.

1980-01-01

Methods to improve the performance of reflux heat pipes for heat recovery applications were examined both analytically and experimentally. Various models for the estimation of reflux heat pipe transport capacity were surveyed in the literature and compared with experimental data. A high transport capacity reflux heat pipe was developed that provides up to a factor of 10 capacity improvement over conventional open tube designs; analytical models were developed for this device and incorporated into a computer program HPIPE. Good agreement of the model predictions with data for R-11 and benzene reflux heat pipes was obtained.

Theoretical analysis to investigate thermal performance of co-axial heat pipe solar collector

Science.gov (United States)

Azad, E.

2011-12-01

The thermal performance of co-axial heat pipe solar collector which consist of a collector 15 co-axial heat pipes surrounded by a transparent envelope and which heat a fluid flowing through the condenser tubes have been predicted using heat transfer analytical methods. The analysis considers conductive and convective losses and energy transferred to a fluid flowing through the collector condenser tubes. The thermal performances of co-axial heat pipe solar collector is developed and are used to determine the collector efficiency, which is defined as the ratio of heat taken from the water flowing in the condenser tube and the solar radiation striking the collector absorber. The theoretical water outlet temperature and efficiency are compared with experimental results and it shows good agreement between them. The main advantage of this collector is that inclination of collector does not have influence on performance of co-axial heat pipe solar collector therefore it can be positioned at any angle from horizontal to vertical. In high building where the roof area is not enough the co-axial heat pipe solar collectors can be installed on the roof as well as wall of the building. The other advantage is each heat pipe can be topologically disconnected from the manifold.

Theoretical analysis to investigate thermal performance of co-axial heat pipe solar collector

Energy Technology Data Exchange (ETDEWEB)

Azad, E. [Iranian Research Organization for Science and Technology (IROST), Advanced Materials and Renewable Energy Department, Tehran (Iran, Islamic Republic of)

2011-12-15

The thermal performance of co-axial heat pipe solar collector which consist of a collector 15 co-axial heat pipes surrounded by a transparent envelope and which heat a fluid flowing through the condenser tubes have been predicted using heat transfer analytical methods. The analysis considers conductive and convective losses and energy transferred to a fluid flowing through the collector condenser tubes. The thermal performances of co-axial heat pipe solar collector is developed and are used to determine the collector efficiency, which is defined as the ratio of heat taken from the water flowing in the condenser tube and the solar radiation striking the collector absorber. The theoretical water outlet temperature and efficiency are compared with experimental results and it shows good agreement between them. The main advantage of this collector is that inclination of collector does not have influence on performance of co-axial heat pipe solar collector therefore it can be positioned at any angle from horizontal to vertical. In high building where the roof area is not enough the co-axial heat pipe solar collectors can be installed on the roof as well as wall of the building. The other advantage is each heat pipe can be topologically disconnected from the manifold. (orig.)

Development of an integrated heat pipe-thermal storage system for a solar receiver

Science.gov (United States)

Keddy, E. S.; Sena, J. T.; Merrigan, M. A.; Heidenreich, G.; Johnson, S.

1987-01-01

The Organic Rankine Cycle (ORC) Solar Dynamic Power System (SDPS) is one of the candidates for Space Station prime power application. In the low Earth orbit of the Space Station approximately 34 minutes of the 94-minute orbital period is spent in eclipse with no solar energy input to the power system. For this period the SDPS will use thermal energy storage (TES) material to provide a constant power output. An integrated heat-pipe thermal storage receiver system is being developed as part of the ORC-SDPS solar receiver. This system incorporates potassium heat pipe elements to absorb and transfer the solar energy within the receiver cavity. The heat pipes contain the TES canisters within the potassium vapor space with the toluene heater tube used as the condenser region of the heat pipe. During the insolation period of the Earth orbit, solar energy is delivered to the heat pipe in the ORC-SDPS receiver cavity. The heat pipe transforms the non-uniform solar flux incident in the heat pipe surface within the receiver cavity to an essentially uniform flux at the potassium vapor condensation interface in the heat pipe. During solar insolation, part of the thermal energy is delivered to the heater tube and the balance is stored in the TES units. During the eclipse period of the orbit, the balance stored in the TES units is transferred by the potassium vapor to the toluene heater tube.

Development of an integrated heat pipe-thermal storage system for a solar receiver

Science.gov (United States)

Keddy, E. S.; Sena, J. T.; Merrigan, M. A.; Heidenreich, G.; Johnson, S.

1987-07-01

The Organic Rankine Cycle (ORC) Solar Dynamic Power System (SDPS) is one of the candidates for Space Station prime power application. In the low Earth orbit of the Space Station approximately 34 minutes of the 94-minute orbital period is spent in eclipse with no solar energy input to the power system. For this period the SDPS will use thermal energy storage (TES) material to provide a constant power output. An integrated heat-pipe thermal storage receiver system is being developed as part of the ORC-SDPS solar receiver. This system incorporates potassium heat pipe elements to absorb and transfer the solar energy within the receiver cavity. The heat pipes contain the TES canisters within the potassium vapor space with the toluene heater tube used as the condenser region of the heat pipe. During the insolation period of the Earth orbit, solar energy is delivered to the heat pipe in the ORC-SDPS receiver cavity. The heat pipe transforms the non-uniform solar flux incident in the heat pipe surface within the receiver cavity to an essentially uniform flux at the potassium vapor condensation interface in the heat pipe. During solar insolation, part of the thermal energy is delivered to the heater tube and the balance is stored in the TES units. During the eclipse period of the orbit, the balance stored in the TES units is transferred by the potassium vapor to the toluene heater tube.

The method for measuring residual stress in stainless steel pipes

International Nuclear Information System (INIS)

Shimov, Georgy; Rozenbaum, Mikhail; Serebryakov, Alexandr; Serebryakov, Andrey

2016-01-01

The main reason of appearance and growth of corrosion damages of the nuclear steam generator heat exchanger tubes is the process of stress-corrosion cracking of metal under the influence of residual tensile stress. Methods used in the production for estimating residual stresses (such as a method of ring samples) allow measuring only the average tangential stress of the pipe wall. The method of ring samples does not allow to assess the level of residual stress in the surface layer of the pipe. This paper describes an experimental method for measuring the residual stresses on the pipe surface by etching a thin surface layer of the metal. The construction and working principle of a trial installation are described. The residual stresses in the wall of the tubes 16 × 1.5 mm (steel AISI 321) for nuclear steam generators is calculated. Keywords: heat exchange pipes, stress corrosion cracking, residual stresses, stress distribution, stress measurement.

78 FR 21105 - Circular Welded Carbon Steel Pipes and Tubes From Thailand: Preliminary Results of Antidumping...

Science.gov (United States)

2013-04-09

.../exporters of the subject merchandise, Saha Thai Steel Pipe (Public) Company, Ltd. (Saha Thai), and Pacific Pipe Company Limited (Pacific Pipe). The period of review (POR) is March 1, 2011, through February 29...) Company, Ltd 0.00 Pacific Pipe Company Limited * * No shipments or sales subject to this review. The firm...

Pressure tube reactor

International Nuclear Information System (INIS)

Susuki, Akira; Murata, Shigeto; Minato, Akihiko.

1993-01-01

In a pressure tube reactor, a reactor core is constituted by arranging more than two units of a minimum unit combination of a moderator sealing pipe containing a calandria tube having moderators there between and a calandria tube and moderators. The upper header and a lower header of the calandria tank containing moderators are communicated by way of the moderator sealing tube. Further, a gravitationally dropping mechanism is disposed for injecting neutron absorbing liquid to a calandria gas injection portion. A ratio between a moderator volume and a fuel volume is defined as a function of the inner diameter of the moderator sealing tube, the outer diameter of the calandria tube and the diameter of fuel pellets, and has no influence to intervals of a pressure tube lattice. The interval of the pressure tube lattice is enlarged without increasing the size of the pressure tube, to improve production efficiency of the reactor and set a coolant void coefficient more negative, thereby enabling to improve self controllability and safety. Further, the reactor scram can be conducted by injecting neutron absorbing liquid. (N.H.)

Twenty-Four Tuba Harmonics Using a Single Pipe Length

Science.gov (United States)

Holmes, Bud; Ruiz, Michael J.

2017-01-01

Harmonics arise naturally from the resonances in strings and pipes. A video demonstration (Ruiz 2016 "YouTube: Tuba Harmonics" (https://youtu.be/souhEzOP9c4)) is provided where a tubist (coauthor Holmes) produces a phenomenal 24 harmonics using a single tuba pipe length by controlling the buzz of his lips. The frequencies of the…

A study on the concentration of CO by the length and the variation of the bent tube of the exhaust pipe for a household gas boiler

International Nuclear Information System (INIS)

Leem, Sa Hwan; Huh, Yong Jeong; Lee, Jong Rark

2008-01-01

Energy and environment become increasingly serious after the industrial revolution. The demand for gas as an ecofriendly energy source is also increasing. With the demand, the installation and the use of gas boilers have also increased, so the damage to human life by the waste gas (CO and CO 2 ) continues increasing every year. Hence, the aim of this study was to investigate the concentration of CO (Carbon Monoxide) by the length and the variation of the bent tube of the exhaust pipe by installing a boiler with the same method as a household boiler and to discover the harm to humans. For the effect of the length, the allowable concentration of CO is 50ppm, and the 3m of the once bent tube starts exceeding the allowable concentration of CO after 5 minutes, and the 4m and 5m starts exceeding after 3 minutes. In addition, the 1m of three times bent tube starts exceeding the allowable concentration of CO after 3 minutes

76 FR 66899 - Certain Circular Welded Non-Alloy Steel Pipe From Brazil, Mexico, the Republic of Korea, and...

Science.gov (United States)

2011-10-28

... construction, shipbuilding, trucking, farm equipment, and related industries. Unfinished conduit pipe is also..., shipbuilding, trucking, farm-equipment, and related industries. Unfinished conduit pipe is also included in the... Steel Tube Works Co., Ltd 11.63 Pusan Steel Pipe Co., Ltd 4.91 All Others 6.37 Taiwan: Kao Hsing Chang...

Manufacture of piping components for nuclear power plants

International Nuclear Information System (INIS)

Bartecek, R.

1983-01-01

Hammer forging of hollow forging ingots, extrusion and elestroslag remelting may be used for the manufacture of large pipes. Technologies have been developed for the manufacture of elbows based on various types of forming. These procedures mainly include the hydraulic pressing of elbows from tubes and the pressing of symmetrical halves of elbows with subsequent welding. The hammer forging of valves, cross pieces, etc., has been replaced by forging and pressing. In order to prevent failures from occurring in the pipes during operation of nuclear power plants, pipes are being made of larger forgings, which reduces the number of welds. This improves the quality of the pipes, reduces production and assembly costs and is metal-saving. (E.S.)

Ultrasonic guided waves in eccentric annular pipes

International Nuclear Information System (INIS)

Pattanayak, Roson Kumar; Balasubramaniam, Krishnan; Rajagopal, Prabhu

2014-01-01

This paper studies the feasibility of using ultrasonic guided waves to rapidly inspect tubes and pipes for possible eccentricity. While guided waves are well established in the long range inspection of structures such as pipes and plates, studies for more complex cross sections are limited and analytical solutions are often difficult to obtain. Recent developments have made the Semi Analytical Finite Element (SAFE) method widely accessible for researchers to study guided wave properties in complex structures. Here the SAFE method is used to study the effect of eccentricity on the modal structures and velocities of lower order guided wave modes in thin pipes of diameters typically of interest to the industry. Results are validated using experiments. The paper demonstrates that even a small eccentricity in the pipe can strongly affect guided wave mode structures and velocities and hence shows potential for pipe eccentricity inspection

Computer simulation of LMFBR piping systems

International Nuclear Information System (INIS)

A-Moneim, M.T.; Chang, Y.W.; Fistedis, S.H.

1977-01-01

Integrity of piping systems is one of the main concerns of the safety issues of Liquid Metal Fast Breeder Reactors (LMFBR). Hypothetical core disruptive accidents (HCDA) and water-sodium interaction are two examples of sources of high pressure pulses that endanger the integrity of the heat transport piping systems of LMFBRs. Although plastic wall deformation attenuates pressure peaks so that only pressures slightly higher than the pipe yield pressure propagate along the system, the interaction of these pulses with the different components of the system, such as elbows, valves, heat exchangers, etc.; and with one another produce a complex system of pressure pulses that cause more plastic deformation and perhaps damage to components. A generalized piping component and a tee branching model are described. An optional tube bundle and interior rigid wall simulation model makes such a generalized component model suited for modelling of valves, reducers, expansions, and heat exchangers. The generalized component and the tee branching junction models are combined with the pipe-elbow loop model so that a more general piping system can be analyzed both hydrodynamically and structurally under the effect of simultaneous pressure pulses

Axial and radial velocities in the creeping flow in a pipe

Directory of Open Access Journals (Sweden)

Zuykov Andrey L'vovich

2014-05-01

Full Text Available The article is devoted to analytical study of transformation fields of axial and radial velocities in uneven steady creeping flow of a Newtonian fluid in the initial portion of the cylindrical channel. It is shown that the velocity field of the flow is two-dimensional and determined by the stream function. The article is a continuation of a series of papers, where normalized analytic functions of radial axial distributions in uneven steady creeping flow in a cylindrical tube with azimuthal vorticity and stream function were obtained. There is Poiseuille profile for the axial velocity in the uniform motion of a fluid at an infinite distance from the entrance of the pipe (at x = ∞, here taken equal to zero radial velocity. There is uniform distribution of the axial velocity in the cross section at the tube inlet at x = 0, at which the axial velocity is constant along the current radius. Due to the axial symmetry of the flow on the axis of the pipe (at r = 0, the radial velocities and the partial derivative of the axial velocity along the radius, corresponding to the condition of the soft function extremum, are equal to zero. The authors stated vanishing of the velocity of the fluid on the walls of the pipe (at r = R , where R - radius of the tube due to its viscous sticking and tightness of the walls. The condition of conservation of volume flow along the tube was also accepted. All the solutions are obtained in the form of the Fourier - Bessel. It is shown that the hydraulic losses at uniform creeping flow of a Newtonian fluid correspond to Poiseuille - Hagen formula.

Reliability-based assessment of polyethylene pipe creep lifetime

International Nuclear Information System (INIS)

Khelif, Rabia; Chateauneuf, Alaa; Chaoui, Kamel

2007-01-01

Lifetime management of underground pipelines is mandatory for safe hydrocarbon transmission and distribution systems. The use of high-density polyethylene tubes subjected to internal pressure, external loading and environmental variations requires a reliability study in order to define the service limits and the optimal operating conditions. In service, the time-dependent phenomena, especially creep, take place during the pipe lifetime, leading to significant strength reduction. In this work, the reliability-based assessment of pipe lifetime models is carried out, in order to propose a probabilistic methodology for lifetime model selection and to determine the pipe safety levels as well as the most important parameters for pipeline reliability. This study is enhanced by parametric analysis on pipe configuration, gas pressure and operating temperature

Reliability-based assessment of polyethylene pipe creep lifetime

Energy Technology Data Exchange (ETDEWEB)

Khelif, Rabia [LaMI-UBP and IFMA, Campus de Clermont-Fd, Les Cezeaux, BP 265, 63175 Aubiere Cedex (France); LR3MI, Departement de Genie Mecanique, Universite Badji Mokhtar, BP 12, Annaba 23000 (Algeria)], E-mail: rabia.khelif@ifma.fr; Chateauneuf, Alaa [LGC-University Blaise Pascal, Campus des Cezeaux, BP 206, 63174 Aubiere Cedex (France)], E-mail: alaa.chateauneuf@polytech.univ-bpclermont.fr; Chaoui, Kamel [LR3MI, Departement de Genie Mecanique, Universite Badji Mokhtar, BP 12, Annaba 23000 (Algeria)], E-mail: chaoui@univ-annaba.org

2007-12-15

Lifetime management of underground pipelines is mandatory for safe hydrocarbon transmission and distribution systems. The use of high-density polyethylene tubes subjected to internal pressure, external loading and environmental variations requires a reliability study in order to define the service limits and the optimal operating conditions. In service, the time-dependent phenomena, especially creep, take place during the pipe lifetime, leading to significant strength reduction. In this work, the reliability-based assessment of pipe lifetime models is carried out, in order to propose a probabilistic methodology for lifetime model selection and to determine the pipe safety levels as well as the most important parameters for pipeline reliability. This study is enhanced by parametric analysis on pipe configuration, gas pressure and operating temperature.

Square through tube

International Nuclear Information System (INIS)

Akita, Junji; Honma, Toei.

1975-01-01

Object: To provide a square through tube involving thermal movement in pipelines such as water supply pump driving turbine exhaust pipe (square-shaped), which is wide in freedom with respect to shape and dimension thereof for efficient installation at site. Structure: In a through tube to be airtightly retained for purpose of decontamination in an atomic power plant, comprising a seal rubber plate, a band and a bolt and a nut for securing said plate, the seal rubber plate being worked into the desired shape so that it may be placed in intimate contact with the concrete floor surface by utilization of elasticity of rubber, thereby providing airtightness at a corner portion of the square tube. (Kamimura, M.)

Study of pipe-whip parameters in pipelines

International Nuclear Information System (INIS)

Guerreiro, J.N.C.; Loula, A.F.D.; Galeao, A.C.N.R.

1980-01-01

The problem of the high energy pipe-whip, assuming an elastic-plastic behavior for the tube material and taking in account the internal pressure, is studied. The constraints are simulated as bilinear springs and viscous dampers. A general research, based on the finite element method was developed to analyse the phenomenon. The influence of the following parameters: gap, damping coefficient, stiffness, constraints positioning and internal pressure of the tube is studied. (Author) [pt

Installation of groundwater observation tubes OL-PVP39 - 40 and drilling of shallow drillhole OL-PP90 at Olkiluoto in Eurajoki 2013

Energy Technology Data Exchange (ETDEWEB)

Toropainen, V. [Suomen Malmi Oy, Espoo (Finland)

2013-11-15

In order to extend the groundwater monitoring network at Olkiluoto, Posiva Oy contracted Suomen Malmi Oy (Smoy) to install new groundwater observation tubes to two locations and to drill one shallow drillhole with a standpipe. The identification numbers of the groundwater observation tubes are OL-PVP39, OL-PVP40A and 40B, and the shallow drillhole is named OL-PP90. The observation tubes were installed and the shallow hole drilled between July 29th and August 6th in 2013. The drilling rig used in the installation work was a GM-200 rig. Drilling equipment consisted of casing tubes (v 90/77 mm) with drilling bit, 55 mm geo rods and 64 mm drilling bits and T76-equipment for drilling the shallow hole. Monitoring pipes (PVC, v 60/52 mm) were lowered into the holes inside the casings. The monitoring pipes consist of a lower section of riser pipe, a middle section of screen pipe and an upper section of riser pipe. The screen pipe slot size is 0.3 mm and the length of the screen section is two or three metres. Protective stainless steel covers with lock-up caps were installed around the monitoring tubes and the shallow drillholes. In addition to the installation of the tubes, the work included water level measurements after installation. The core samples of the shallow drillhole were logged and reported by geologist. Geological logging included the following parameters: lithology, foliation, fracture parameters, fractured zones, core loss, weathering, fracture frequency, RQD and rock quality. (orig.)

Inner tubes cutting method by electrical arc saw

International Nuclear Information System (INIS)

Thome, P.

1990-01-01

The research program deals on the definition of tools used for dismantling steam generator tubes bundle of PWR and on tool used for cutting pipes of great diameter by using the process of cutting by electrical arc saw. The remote tools are used for cutting by the interior pipes of contamined circuits [fr

Theoretical model of an evacuated tube heat pipe solar collector integrated with phase change material

International Nuclear Information System (INIS)

Naghavi, M.S.; Ong, K.S.; Badruddin, I.A.; Mehrali, M.; Silakhori, M.; Metselaar, H.S.C.

2015-01-01

The purpose of this paper is to model theoretically a solar hot water system consisting of an array of ETHPSC (evacuated tube heat pipe solar collectors) connected to a common manifold filled with phase change material and acting as a LHTES (latent heat thermal energy storage) tank. Solar energy incident on the ETHPSC is collected and stored in the LHTES tank. The stored heat is then transferred to the domestic hot water supply via a finned heat exchanger pipe placed inside the tank. A combination of mathematical algorithms is used to model a complete process of the heat absorption, storage and release modes of the proposed system. The results show that for a large range of flow rates, the thermal performance of the ETHPSC-LHTES system is higher than that of a similar system without latent heat storage. Furthermore, the analysis shows that the efficiency of the introduced system is less sensitive to the draw off water flowrate than a conventional system. Analysis indicates that this system could be applicable as a complementary part to conventional ETHPSC systems to be able to produce hot water at night time or at times with weak radiation. - Highlights: • The ETHPSC is integrated with PCM at manifold side for night hot water demands. • The thermal performance of the ETHPSC-PCM is often higher than the baseline model. • The efficiency of the proposed model is stable for different flow rates. • Using PCM as thermal storage increases reliability on the performance of the system.

Cryogenic and Gas System Piping Pressure Tests (A Collection of PT Permits)

International Nuclear Information System (INIS)

Rucinski, Russell A.

2002-01-01

This engineering note is a collection of pipe pressure testing documents for various sections of piping for the D-Zero cryogenic and gas systems. High pressure piping must conform with FESHM chapter 5031.1. Piping lines with ratings greater than 150 psig have a pressure test done before the line is put into service. These tests require the use of pressure testing permits. It is my intent that all pressure piping over which my group has responsibility conforms to the chapter. This includes the liquid argon and liquid helium and liquid nitrogen cryogenic systems. It also includes the high pressure air system, and the high pressure gas piping of the WAMUS and MDT gas systems. This is not an all inclusive compilation of test documentation. Some piping tests have their own engineering note. Other piping section test permits are included in separate safety review documents. So if it isn't here, that doesn't mean that it wasn't tested. D-Zero has a back up air supply system to add reliability to air compressor systems. The system includes high pressure piping which requires a review per FESHM 5031.1. The core system consists of a pressurized tube trailer, supply piping into the building and a pressure reducing regulator tied into the air compressor system discharge piping. Air flows from the trailer if the air compressor discharge pressure drops below the regulator setting. The tube trailer is periodically pumped back up to approximately 2000 psig. A high pressure compressor housed in one of the exterior buildings is used for that purpose. The system was previously documented, tested and reviewed for Run I, except for the recent addition of piping to and from the high pressure compressor. The following documents are provided for review of the system: (1) Instrument air flow schematic, drg. 3740.000-ME-273995 rev. H; (2) Component list for air system; (3) Pressure testing permit for high pressure piping; (4) Documentation from Run I contained in D-Zero Engineering note

On the performance of air conditioner with heat pipe for cooling air in the condenser

Energy Technology Data Exchange (ETDEWEB)

Naphon, Paisarn, E-mail: paisarnn@swu.ac.t [Thermo-Fluids and Heat Transfer Enhancement Laboratory (TFHT), Department of Mechanical Engineering, Faculty of Engineering, Srinakharinwirot University, 63 Rangsit-Nakhornnayok Rd., Ongkharak, Nakhorn-Nayok 26120 (Thailand)

2010-11-15

Improvement of the air conditioning system performance by using the heat pipe for cooling air before entering the condenser is presented. In the experiment, the heat pipe is fabricated from the straight copper tube with the diameter and length of 10, 600 mm, respectively. The arrangements of the heat pipe sets are arranged in the staggered layout with the tube rows of 1, 2, 3. R134a refrigerant is used as working fluid in the heat pipe set for this present study. By comparing with a conventional air conditioning system, the air conditioning system with three rows of heat pipe gives the highest COP and EER with increasing of 6.4%, 17.5%, respectively. On the global warming and environment problems, the results of this study are expected to lead to guidelines that will allow the improved performance of the air conditioning systems which reduce its energy consumption.

On the performance of air conditioner with heat pipe for cooling air in the condenser

International Nuclear Information System (INIS)

Naphon, Paisarn

2010-01-01

Improvement of the air conditioning system performance by using the heat pipe for cooling air before entering the condenser is presented. In the experiment, the heat pipe is fabricated from the straight copper tube with the diameter and length of 10, 600 mm, respectively. The arrangements of the heat pipe sets are arranged in the staggered layout with the tube rows of 1, 2, 3. R134a refrigerant is used as working fluid in the heat pipe set for this present study. By comparing with a conventional air conditioning system, the air conditioning system with three rows of heat pipe gives the highest COP and EER with increasing of 6.4%, 17.5%, respectively. On the global warming and environment problems, the results of this study are expected to lead to guidelines that will allow the improved performance of the air conditioning systems which reduce its energy consumption.

Automatic detection of ''bore slug'' in tubes; Detection automatique des manques de metal internes sur tubes

Energy Technology Data Exchange (ETDEWEB)

Bisiaux, B.; Deutsch, S.; Tailleux, O.; Mette, F. [CEV Vallourec, Aulnoye (France)

2001-07-01

During the tube manufacturing for the petroleum industry, the lacks of internal metal (called Bore Slug) can be created during the hot rolling. These large defects are not good detected by the classic UT and by the wall thickness measurement. That's why VALLOUREC developed an automatic UT device which works by transmission. Nevertheless, this system is too little selective and can cause no doubtful pipes (tubes good detected bad). We adapted a Bore Slug control system on the VMOG UK RP20 at the end of August. The results are rather good and showed a good detection of the Bore Slug and very little no doubtful pipes. (authors)

Feasibility study on the application of a heat-pipe type adsorption chiller

Energy Technology Data Exchange (ETDEWEB)

Ahn, Sang Hyeok; Chung, Jae Dong [Dept. of Mechanical Engineering, Sejong University, Seoul (Korea, Republic of); Kwon, Oh Kyung [Energy System R and D Group, Korea Institute of Industrial Technology, Cheonan (Korea, Republic of)

2017-01-15

A parametric study on a heat-pipe type adsorption chiller with SWS-1L (mesoporous silica gel impregnated with CaCl{sub 2}) and water pair was conducted using a numerical method in this research. A heat pipe that is in direct contact with the adsorbent is applied to the adsorption chiller to improve the heat transfer capacity of the adsorption bed. A feasibility study was performed on the heat-pipe type adsorption bed with a single layer. The Coefficient of performance (COP) and the Specific cooling power (SCP) were 0.231 and 844.8 W/kg, respectively. These values are lower than the system performance values of the existing fin-tube type adsorption bed. However, when the number of bed layers was increased to seven, the COP and SCP of the heat-pipe type adsorption bed were 0.520 and 752.4 W/kg, respectively. These values are 5.25 % and 39.8 % higher than the COP and SCP, respectively, of the fin-tube type adsorption bed. These findings indicate that the heat-pipe type adsorption bed can potentially address the disadvantage caused by the system size of the adsorption chiller. A parametric study was also conducted for six design parameters, namely, number of layers, heat pipe pitch, heat pipe radius, fin width, fin spacing, and hot water temperature.

Feasibility study on the application of a heat-pipe type adsorption chiller

International Nuclear Information System (INIS)

Ahn, Sang Hyeok; Chung, Jae Dong; Kwon, Oh Kyung

2017-01-01

A parametric study on a heat-pipe type adsorption chiller with SWS-1L (mesoporous silica gel impregnated with CaCl_2) and water pair was conducted using a numerical method in this research. A heat pipe that is in direct contact with the adsorbent is applied to the adsorption chiller to improve the heat transfer capacity of the adsorption bed. A feasibility study was performed on the heat-pipe type adsorption bed with a single layer. The Coefficient of performance (COP) and the Specific cooling power (SCP) were 0.231 and 844.8 W/kg, respectively. These values are lower than the system performance values of the existing fin-tube type adsorption bed. However, when the number of bed layers was increased to seven, the COP and SCP of the heat-pipe type adsorption bed were 0.520 and 752.4 W/kg, respectively. These values are 5.25 % and 39.8 % higher than the COP and SCP, respectively, of the fin-tube type adsorption bed. These findings indicate that the heat-pipe type adsorption bed can potentially address the disadvantage caused by the system size of the adsorption chiller. A parametric study was also conducted for six design parameters, namely, number of layers, heat pipe pitch, heat pipe radius, fin width, fin spacing, and hot water temperature

The development and manufacture of size for size feeder pipe for feeder replacement

International Nuclear Information System (INIS)

Legate, G.; Schreiter, D.; Townley, N.

2008-01-01

The recently recognised problem of feeder pipe thinning created a unique sourcing problem. Operators require relatively small quantities of nuclear class 1 seamless feeder pipe for such replacement which prior to the introduction of this product in 2006 was not available. It was desired that the pipe be produced at the exact size of the pipe currently in use at the specific reactor site (feeder pipe size varies from site to site). Secondly the pipe had to be made in conformance to the original code year of issue and to conform to the intent of the original material specifications. Finally a supply strategy had to be implemented allowing for timely manufacture of replacement piping. This presentation will report upon how replacement size for size feeder tube was developed and is currently manufactured at Nu-Tech Precision Metals. The paper will also detail the current supply strategy to ensure timely manufacture of the product.

Design rules for piping: Plastic stability of straight parts under level D loadings

International Nuclear Information System (INIS)

Touboul, F.; Ben Djidia, M.; Acker, D.

1989-01-01

Design rules for piping, elaborated for Fast Breeder Reactors, are based on analysis performed for Pressure Water Reactors. Interpretation of largely diversified straight parts tests, enable us to validate and improve existing rules and to propose a more suitable formula. Design rules for piping appear to be non conservative for austenitic thin tubes in bending or torsion. By introducing a B 2 coefficient, geometrically dependent, the gap between thin and thick tubes may be withheld. Conservatism of rules can be ensured by considering the allowable stress defined by ASME, Section III, Appendix F

Experimental investigation of thermal mixing phenomena in a tee pipe

Energy Technology Data Exchange (ETDEWEB)

Chen, Mei-Shiue; Hsieh, Huai-En; Zhang, Zhi-Yu; Pei, Bau-Shi [National Tsing Hua Univ., Taiwan (China). Inst. of Nuclear Engineering and Science

2015-05-15

T-pipe designs have been widely used in the industry. Among them, mixing of hot and cold water is a common application. In the mixing process, cold and hot fluids are respectively injected through main and branch pipes, and are mixed in the downstream area of T-tube. High temperature hot water flows through the main pipe for a long time; hence, the pipe wall is at high temperatures. The fluid injected into the branch pipe is a cooling fluid. After mixing, the wall of the main pipe is under high thermal fluctuations causing strong thermal stresses, which will eventually lead to pipe damage and water loss. Through flow rate adjustments of the branch and main pipes, when the branch/main velocity ratio was greater than 7.8, showing that cold water hit the bottom of the main pipe and created a reverse flow. This reverse flow created large thermal stresses on the wall. Hence, the branch/main velocity ratio and the hot-water-mixing phenomenon are the focus of this study.

A elastic-plastic model for pipe whip

International Nuclear Information System (INIS)

Maneschy, J.E.A.

1980-04-01

The dynamic behavior of a cantilever beam simulating a pipe after full rupture at a given cross-section is investigated. This problem, known as pipe whip, has to be analysed within the frame of plastic deformations. The physical model is represented by a cantilever, subjected to a step-load at the free end, and a support designed to absorb the maximum possible kinetic energy of the tube generated by suddenly applied force. The analysis is performed using the Bernoulli theory for straight beams, assuming for the moment-curvature relation a bi-linear law. (author)

Installation of groundwater observation tubes OL-PVP36-38 and drilling of shallow drillholes OL-PP70-71 at Olkiluoto in Eurajoki 2011

International Nuclear Information System (INIS)

Toropainen, V.

2012-05-01

In order to widen the groundwater monitoring network at Olkiluoto, Posiva Oy contracted Suomen Malmi Oy (Smoy) to install new groundwater observation tubes to three locations and to drill two shallow drillholes with standpipes. The identification numbers of the groundwater observation tubes are OL-PVP36, OL-PVP37A, 37B, 37C, OL-PVP38A, 38B, 38C and 38D, and the shallow drillholes are named OL-PP70 and OL-PP71. The observation tubes were installed and the shallow holes drilled between September 22nd and October 12th in 2011. The drilling rig used in the installation work was a GM-200 rig. Drilling equipment consisted of casing tubes (90/77 mm) with drilling bit, 55 mm geo rods and 64 mm drilling bits and T76-equipment for drilling the shallow holes. Monitoring pipes (PVC, 60/52 mm) were lowered into the holes inside the casings. The monitoring pipes consist of a lower section of riser pipe, a middle section of screen pipe and an upper section of riser pipe. The screen pipe slot size is 0.3 mm and the length of the screen section is two metres. Protective stainless steel covers with lock-up caps were installed around the monitoring tubes and the shallow drillholes. In addition to the installation of the tubes, the work included water level measurements after installation. The core samples of the shallow drillholes were logged and reported by geologist. Geological logging included the following parameters: lithology, foliation, fracture parameters, fractured zones, core loss, weathering, fracture frequency, RQD and rock quality. (orig.)

Installation of groundwater observation tubes OL-PVP36-38 and drilling of shallow drillholes OL-PP70-71 at Olkiluoto in Eurajoki 2011

Energy Technology Data Exchange (ETDEWEB)

Toropainen, V. [Suomen Malmi Oy, Espoo (Finland)

2012-05-15

In order to widen the groundwater monitoring network at Olkiluoto, Posiva Oy contracted Suomen Malmi Oy (Smoy) to install new groundwater observation tubes to three locations and to drill two shallow drillholes with standpipes. The identification numbers of the groundwater observation tubes are OL-PVP36, OL-PVP37A, 37B, 37C, OL-PVP38A, 38B, 38C and 38D, and the shallow drillholes are named OL-PP70 and OL-PP71. The observation tubes were installed and the shallow holes drilled between September 22nd and October 12th in 2011. The drilling rig used in the installation work was a GM-200 rig. Drilling equipment consisted of casing tubes (90/77 mm) with drilling bit, 55 mm geo rods and 64 mm drilling bits and T76-equipment for drilling the shallow holes. Monitoring pipes (PVC, 60/52 mm) were lowered into the holes inside the casings. The monitoring pipes consist of a lower section of riser pipe, a middle section of screen pipe and an upper section of riser pipe. The screen pipe slot size is 0.3 mm and the length of the screen section is two metres. Protective stainless steel covers with lock-up caps were installed around the monitoring tubes and the shallow drillholes. In addition to the installation of the tubes, the work included water level measurements after installation. The core samples of the shallow drillholes were logged and reported by geologist. Geological logging included the following parameters: lithology, foliation, fracture parameters, fractured zones, core loss, weathering, fracture frequency, RQD and rock quality. (orig.)

Flow induced vibrations of piping

International Nuclear Information System (INIS)

Gibert, R.J.; Axisa, F.

1977-01-01

In order to design the supports of piping systems, estimations of the vibrations induced by the fluid conveyed through the pipes are generally needed. For that purpose it is necessary to calculate the model parameters of liquid containing pipes. In most computer codes, fluid effects are accounted for just by adding the fluid mass to the structure. This may lead to serious errors. This paper presents a method to take into account these effects, by solving a coupled mechanical-acoustical problem: the computer code TEDEL of the C.E.A /D.E.M.T. System, based on the finite-elements method, has been extended to calculate simultaneously the pressure fluctuations in the fluid and the vibrations of the pipe. By this way the mechanical-acoustical coupled eigenmodes of any piping system can be obtained. These eigenmodes are used to determine the response of the system to various sources. Equations have been written in the hypohesis that acoustical wave lengths remain large compared to the diameter of the pipe. The method has been checked by an experiment performed on the GASCOGNE loop at D.E.M.T. The piping system under test consists of a tube with four elbows. The circuit is ended at each extremity by a large vessel which performs acoustical isolation by generating modes for the pressure. Excitation of the circuit is caused by a valve located near the downstream vessel. This provides an efficient localised broad band acoustical source. The comparison between the test results and the calculations has shown that the low frequency resonant characteristics of the pipe and the vibrational amplitude at various flow-rates can be correctly predicted

Decontamination laboratory design for iron pipes contaminated with uranium and thorium series

International Nuclear Information System (INIS)

Sahyun, Adelia; Sordi, Gian M.; Ghobril, Carlos N.; Puga Sanches, Matias; Rodrigues, Demerval L.

2008-01-01

The Brazilian soil is very rich in the ore processing, after some time, the pipes are contaminated with trace levels of uranium and thorium. When the pipes are exchanged, to recovery the funds, the best is to sell them as scrap, however, because they are contaminated and present a considerable amount of dose can not be marketed until they are decontaminated. The question is that the tube is incrusted with the contaminated material, and is difficult to remove it. For the removal this material, that comes to be 2 inches thick, for the larger pipes diameter, requires special equipment as a motor-pump units with ultra high pressure water jetting, of the order of 40000 psi. The purpose of this paper is to suggest a design of one laboratory able to perform the decontamination avoiding large scale production of radioactive wastes. The solids and liquids wastes produced during the process of decontamination will be collected in different containers and classified according to their contamination level. The laboratory was designed to facilitate its decontamination with a minimum dose for their operators. The most difficult question to be solved during the project, was to perform the laboratory decontamination during the pipe decontamination in continuous operation since we can't stop the process for the reason of it expensive cost. The paper will show how will be made all the steps of the tubes decontamination and the laboratory decontamination. It will be shown how we collect the liquids and solids wastes, separate, for their classification. After the pipe, decontamination we show as will be measure the dose to release or to return for the laboratory to development a further decontamination. At last, it will show the temporary storage place for the decontaminated pipes that will be later collected as scrap. (author)

Performance Measurements of a 7 mm-Diameter Hydrogen Heat Pipe

International Nuclear Information System (INIS)

Abdel-Bary, M.; Abdel-Samad, S.; Kiliana, K.; Ritman, J.; Abdel-Bary, M.; Abdel-Samad, S.

2008-01-01

A gravity assisted heat pipe with 7-mm diameter has been developed and tested to cool a liquid hydrogen target for extracted beam experiments at COSY. The liquid flowing down from the condenser surface is separated from the vapor flowing up by a thin wall 3 mm diameter plastic tube located concentrically inside the heat pipe. The heat pipe was tested at different inclination angles with respect to the horizontal plane. The heat pipe showed good operating characteristics because of the low radiation heat load from the surroundings, low heat capacity due to the small mass, higher sensitivity to heat loads (to overcome the heat load before the complete vaporization of the liquid in the target cell) due to the higher vapor speed inside the heat pipe which transfers the heat load to the condenser

LHCb celebrates completion of its beam pipe

CERN Multimedia

2007-01-01

Members of the LHCb collaboration and of the AT and TS Departments are ready to pop open the champagne bottles and celebrate the complete installation and commissioning of the LHCb experiment’s beam pipe. Members of the LHCb collaboration and of the AT and TS Departments gather near the newly completed beam pipe in the foreground. All four sections of LHCb’s beam pipe have been installed, interconnected, pumped down and baked out.. Three of the conical tubes are made of beryllium in order to minimize the level of background in the experiment, while the fourth and largest section is composed of stainless steel. The first of the beryllium sections, an important connection to the Vertex Locator vacuum vessel (VELO) was installed in August 2006 (see Bulletin No. 37/2006). One of the more challenging tasks was the installation of the longest (6 m) piece of beryllium beam pipe through the 2.4 m long RICH2 detector in January 2006. Deli...

A novel method for coiled tubing installation

Energy Technology Data Exchange (ETDEWEB)

Simpson, Peter J. [2H Offshore, Houston, TX (United States); Tibbetts, David [Aquactic Engineering and Construction Ltd., Aberdeen (United Kingdom)

2009-12-19

Installation of flexible pipe for offshore developments is costly due to the physical cost of the flexible pipe, expensive day rates and the availability of suitable installation vessels. Considering the scarcity of flexible pipe in today's increasingly demanding and busy market, operators are seeking a cost effective solution for installing piping in a range of water depths using vessels which are readily on hand. This paper describes a novel approach to installing reeled coiled tubing, from 1 inch to 5 inch diameter, from the back of a small vessel in water depths from 40 m up to around 1000 m. The uniqueness of the system is the fact that the equipment design is modular and compact. This means that when disassembled, it fits into standard 40 ft shipping containers, and the size allows it to be installed on even relatively small vessels of opportunity, such as anchor handling or installation vessels, from smaller, and cheaper quay side locations. Such an approach is the ideal solution to the problem faced by operators, in that it allows the installation of cheaper, readily available coiled tubing, from cost-effective vessels, which do not need to transit to a pick up the system. (author)

Ductile failure of pipes with defects under combined pressure and bending

International Nuclear Information System (INIS)

Darlaston, B.J.L.; Harrison, R.P.

1977-01-01

The main part of the experimental programme was carried out on 3.5'' diam. pipes with a wall thickness of 0.064''. Various lengths of defect were assessed but only two depths, 0.044'' and 0.060''. Some full penetration defect tests were carried out under bending loading. The defects were 0.012'' wide and nominally flat bottomed. The tensile properties of the pipes were determined by taking specimens from each of the tubes. The pipes were exposed to pressure only test, bending only test and combined bending and pressure test. The results are given in tables. The observations led to the postulation of a design rule relating to the effect of defect in pipes under combined internal pressure and bending. It applies only to ductile situations in which the mode of failure is by a collapse mechanism: If the failure of a pipe containing an axial defect occurs by plastic collapse then provided the bending moment does not exceed half that for collapse due to bending alone, it will have a negligible effect on the failure pressure. (J.B.)

Temperature control of thermal-gas-dynamical installation in cleaning oil-well tubes

Science.gov (United States)

Penner, V. A.; Martemyanov, D. B.; Pshenichnikova, V. V.

2017-08-01

The article provides the study results of cleaning oil-well tubes, the oil-well tube failure reasons for service by their types have been considered. The chemical method of cleaning oil-well tubes as the least expensive has been reviewed when acid solution moves to the interptube space mixing up with oil and liquidates paraffin and pitches deposits on the internal pipe surface. Except the chemical method of pipes cleaning the mechanical one was considered as well. Also the disadvantages -such as the low productivity of cleaning and design complexity- of this deposits removal method on the internal oil-well tube surface have been considered. An effective method for cleaning oil-well tubing from paraffin and pitches by the thermodynamic plant based on the aircraft engine has been introduced for the first time. The temperature distribution graph in the gas stream at the engine output has been given.

77 FR 64465 - Circular Welded Carbon-Quality Steel Pipe From the United Arab Emirates: Final Affirmative...

Science.gov (United States)

2012-10-22

... of the Government of the UAE's (``GUAE''), Universal Tube and Plastic Industries, Ltd., KHK... Universal Tube and Plastic Industries, Ltd.; KHK 2.06 Scaffolding and Formwork LLC; Universal Tube and Pipe... Industry Usage Data Comment 4 Countervailability of Alita's Tariff Exemptions B. Subsidies Within the Jebel...

Hydrogen isotope effect through Pd in hydrogen transport pipe

International Nuclear Information System (INIS)

Tamaki, Masayoshi

1992-01-01

This investigation concerns hydrogen system with hydrogen transport pipes for transportation, purification, isotope separation and storage of hydrogen and its isotopes. A principle of the hydrogen transport pipe (heat pipe having hydrogen transport function) was proposed. It is comprised of the heat pipe and palladium alloy tubes as inlet, outlet, and the separation membrane of hydrogen. The operation was as follows: (1) gas was introduced into the heat pipe through the membrane in the evaporator; (2) the introduced gas was transported toward the condenser by the vapor flow; (3) the transported gas was swept and compressed to the end of the condenser by the vapor pressure; and (4) the compressed gas was exhausted from the heat pipe through the membrane in the condenser. The characteristics of the hydrogen transport pipe were examined for various working conditions. Basic performance concerning transportation, evacuation and compression was experimentally verified. Isotopic dihydrogen gases (H 2 and D 2 ) were used as feed gas for examining the intrinsic performance of the isotope separation by the hydrogen transport pipe. A simulated experiment for hydrogen isotope separation was carried out using a hydrogen-helium gas mixture. The hydrogen transport pipe has a potential for isotope separation and purification of hydrogen, deuterium and tritium in fusion reactor technology. (author)

Heating tubes of cross-linked polyethylene

International Nuclear Information System (INIS)

Knoeppler, H.; Hoffmann, M.

1981-01-01

Oxygen permeability of plastic tubes for floor heating systems was measured as a function of the reduced oxygen content of water in plastic tubes at a flow rate of 0.5 m/s and a temperature of 30 0 C and as a function of oxygen uptake of low-oxygen water in floor heating tubes. Pipes of VEP, periodically cross-linked polyethylene (Engels process), polypropylene copolymeride, and polybutene were compared. The permeability of periodically cross-linked polyethylene is twice as high as that of VEP. Measurements, results, and consequences for floor heating systems are discussed. (KH) [de

Apparatus and method for pulsed laser deposition of materials on wires and pipes

Science.gov (United States)

Fernandez, Felix E.

2003-01-01

Methods and apparatuses are disclosed which allow uniform coatings to be applied by pulsed laser deposition (PLD) on inner and outer surfaces of cylindrical objects, such as rods, pipes, tubes, and wires. The use of PLD makes this technique particularly suitable for complex multicomponent materials, such as superconducting ceramics. Rigid objects of any length, i.e., pipes up to a few meters, and with diameters from less than 1 centimeter to over 10 centimeters can be coated using this technique. Further, deposition is effected simultaneously onto an annular region of the pipe wall. This particular arrangement simplifies the apparatus, reduces film uniformity control difficulties, and can result in faster operation cycles. In addition, flexible wires of any length can be continuously coated using the disclosed invention.

Study of the performances of acoustic emission testing for glass fibre reinforced plastic pipes containing defects

International Nuclear Information System (INIS)

Villard, D.; Vidal, M.C.

1995-08-01

Glass fibre reinforced plastic pipes are more and more often used, in nuclear power plants, for building or replacement of water pipings classified 'nuclear safety'. Tests have been performed to evaluate the performances of acoustic emission testing for in service inspection of these components. The tests were focused on glass fibre reinforced polyester and vinyl-ester pipes, in as received conditions or containing impacts, and intentionally introduced defects. They have been carried out by CETIM, following the ASTM Standard E 1118 (code CARP), to a maximum pressure lever of 25 Bar The results show that the CARP procedure can be used for detection of defects and evaluation of their noxiousness towards internal pressure: most of the tubes containing low energy impacts could not be distinguished from tubes without defect; on the other hand the important noxiousness of lacks of impregnation of roving layer appeared clearly. Complementary tests have been performed on some tubes at a more important pressure lever, for which the damage of the tubes in enough to deteriorate there elastic properties. The results showed that CARP procedure give valuable informations on damage level. It would be interesting to evaluate acoustic emission on tubes containing realistic in-service degradations. (author). 11 refs., 15 figs., 6 tabs., 2 appends

ANALYSIS OF MATERIALS IN AN EXPERIMENTAL TESTING PIPE SYSTEM FOR AN INHIBITOR OF MUSSEL KILL

Energy Technology Data Exchange (ETDEWEB)

Daniel P. Molloy

2003-06-04

A comprehensive series of 16 laboratory experiments demonstrated that the presence of vinyl tubing within a recirculating pipe system was responsible for lowering zebra mussel kill following treatment with the bacterium Pseudomonas fluorescens. All vinyl tubing was replaced in all testing units with silicone tubing, and high mussel kill (>95%) was then obtained.

Precision heat forming of tetrafluoroethylene tubing

Science.gov (United States)

Ruiz, W. V.; Thatcher, C. S. (Inventor)

1981-01-01

An invention that provides a method of altering the size of tetrafluoroethylene tubing which is only available in limited combination of wall thicknesses and diameter are discussed. The method includes the steps of sliding the tetrafluoroethylene tubing onto an aluminum mandrel and clamping the ends of the tubing to the mandrel by means of clamps. The tetrafluorethylene tubing and mandrel are then placed in a supporting coil which with the mandrel and tetrafluorethylene tubing are then positioned in a insulated steel pipe which is normally covered with a fiber glass insulator to smooth out temperature distribution therein. The entire structure is then placed in an event which heats the tetrafluorethylene tubing which is then shrunk by the heat to the outer dimension of the aluminum mandrel. After cooling the aluminum mandrel is removed from the newly sized tetrafluorethylene tubing by a conventional chemical milling process.

Flow and oscillations in collapsible tubes: Physiological applications ...

Indian Academy of Sciences (India)

pressure changes associated with fluid flow in the tube may be enough to generate large area changes. Collapsible ... As a very simple model, consider a single, uniform pipe containing viscous fluid flowing steadily at volume ..... (1986). For each mode the instability occurs through a Hopf bifurcation, which is supercritical.

SEALING LARGE-DIAMETER CAST-IRON PIPE JOINTS UNDER LIVE CONDITIONS

Energy Technology Data Exchange (ETDEWEB)

Kiran M. Kothari; Gerard T. Pittard

2003-06-01

Utilities in the U.S. operate over 75,000 km (47,000 miles) of old cast-iron pipes for gas distribution. The bell-and-spigot joints tend to leak as these pipes age. Current repair practices are costly and highly disruptive. The objective of this program is to design, test and commercialize a robotic system capable of sealing multiple cast-iron bell and spigot joints from a single pipe entry point. The proposed system will perform repairs while the pipe remains in service by traveling through the pipe, cleaning each joint surface, and attaching a stainless-steel sleeve lined with an epoxy-impregnated felt across the joint. This approach will save considerable time and labor, avoid traffic disruption, and eliminate any requirement to interrupt service (which results in enormous expense to utilities). Technical challenges include: (1) repair sleeves must compensate for diametric variation and eccentricity of cast-iron pipes; (2) the assembly must travel long distances through pipes containing debris; (3) the pipe wall must be effectively cleaned in the immediate area of the joint to assure good bonding of the sleeve; and (4) an innovative bolt-on entry fitting is required to conduct repair operations on live mains. The development effort is divided into eleven tasks. Task 1-Program Management was previously completed. Two reports, one describing the program management plan and the other consisting of the technology assessment, were submitted to the DOE COR in the first quarter. Task 2-Establishment of Detailed Design Specifications and Task 3-Design and Fabricate Ratcheting Stainless-Steel Repair Sleeves are now well underway. First-quarter activities included conducting detailed analyses to determine the capabilities of coiled-tubing locomotion for entering and repairing gas mains and the first design iteration of the joint-sealing sleeve. The maximum horizontal reach of coiled tubing inside a pipeline before buckling prevents further access was calculated for a wide

A flexible film type EMAT for inspection of small diameter pipe

Energy Technology Data Exchange (ETDEWEB)

Pei, Cuixiang; Xiao, Pan; Zhao, Siqi; Chen, Zhenmao [Xi' an Jiaotong University, Xi' an (China); Takagi, Toshiyuki [Institute of Fluid Science, Tohoku University, Sendai (Japan)

2017-08-15

Pipe structures are widely applied in industries, and different kinds of defects may occur in the structures during their long-time service. For non-destructive testing of defects in pipes of small diameter, it has to be conducted from the inner side of the pipe when there is no space for detection from the outside or the geometry of the outside tube surface is too complicated. In this work, a flexible film type Electromagnetic acoustic transducer (EMAT) probe with a dual coil configuration is developed. The new probe is flexible and can be inserted into the pipe for inspection. First, the feasibility of the new probe was studied through numerical simulation. Then the feasibility of the proposed flexible EMAT for detection of wall thinning in small diameter pipe was verified experimentally. It was found that the new EMAT method is suitable for the detection of wall thinning defects for small pipes.

Magnetic forces on a ferromagnetic HT-9 first wall/blanket and coolant pipe

International Nuclear Information System (INIS)

Lechtenberg, T.A.; Dahms, C.; Attaya, H.; Univ. of Wisconsin, Madison)

1984-01-01

The GFUN 3D code was used to model the toroidal fields and determine the magnetic body forces on the STARFIRE design for coolant pipes exiting the first wall sector and first wall/blanket modules. The HT-9 coolant pipes were modeled on the basis of a square bar having the same length and material volume as the coolant pipes. The stress analysis was performed using these magnetic forces applied to a pipe of 4 meters length, 8.25 cm O.D., and 0.75 cm thickness by the MODSAP stress analysis code. For the first wall/blanket module, GFUN 3D does not allow full modeling of the complex thin-walled structure or numerous small tubes because of the element aspect ratio limitations. Therefore, to obtain three dimensional loads, a solid homogeneous equivalent structure was used

Simulation of boiling flow in evaporator of separate type heat pipe with low heat flux

International Nuclear Information System (INIS)

Kuang, Y.W.; Wang, Wen; Zhuan, Rui; Yi, C.C.

2015-01-01

Highlights: • A boiling flow model in a separate type heat pipe with 65 mm diameter tube. • Nucleate boiling is the dominant mechanism in large pipes at low mass and heat flux. • The two-phase heat transfer coefficient is less sensitive to the total mass flux. - Abstract: The separate type heat pipe heat exchanger is considered to be a potential selection for developing passive cooling spent fuel pool – for the passive pressurized water reactor. This paper simulates the boiling flow behavior in the evaporator of separate type heat pipe, consisting of a bundle of tubes of inner diameter 65 mm. It displays two-phase characteristic in the evaporation section of the heat pipe working in low heat flux. In this study, the two-phase flow model in the evaporation section of the separate type heat pipe is presented. The volume of fluid (VOF) model is used to consider the interaction between the ammonia gas and liquid. The flow patterns and flow behaviors are studied and the agitated bubbly flow, churn bubbly flow are obtained, the slug bubble is likely to break into churn slug or churn froth flow. In addition, study on the heat transfer coefficients indicates that the nucleate boiling is the dominant mechanism in large pipes at low mass and heat flux, with the heat transfer coefficient being less sensitive to the total mass flux

Manufacture of seamless stainless steel tubings and related equipment

International Nuclear Information System (INIS)

Wali, D.K.; Chaudhary, S.

1997-01-01

Production of seamless tubes for special application is one of the important production activities of Nuclear Fuel Complex (NFC), Hyderabad. NFC had set up facility of Hot Extrusion Press and Cold Pilger Mills with related finishing and inspection equipment for manufacturing quality seamless tubes of zirconium alloy for application in nuclear power reactors in early 70''s. Being aware that the demand for seamless tube in a developing economy gradually increases till it reaches around 30 to 40% of the total requirement of tubes and pipes and also of the fact that manufacturing technology developed for production of zircaloy seamless tubes for nuclear application, can easily be harnessed and spinned off for production of seamless tubes in materials generally difficult to hot roll (in other than extrusion process), NFC augmented its seamless tube manufacturing facility by adding, a vertical piercing press, series of induction furnaces and large size pilger mills to meet existing market demand of power sector, engineering, fertilisers and petro chemical industries and any other specialised applications

Machining of the nuclear tube sheet with small hole diameter

International Nuclear Information System (INIS)

Lin Lifeng

2010-01-01

Regarding the tube sheet for the heat exchanger of Qinshan Phase II extension project, its material is 00Cr19Ni10 forgings, the tube sheet thickness is 125 mm, requiring 178-φ10.35 0 +0.05 hole, the tube array shall take the shape of equilateral triangle, the center distance is 15 mm, and the tube hole roughness is Ra 3.2. The guide sleeve shall be adopted for positioning prior to machining of the high precision small hole of the thick tube sheet, and the gun drill and BTA drill shall be adopted for testing, finally BTA drilling with internal chip removal shall be adopted, this method shall overcome the disadvantage factor of BTA drilling and shall be the new approach for drilling. The diameter of BTA drill is φ10.34 mm. The machined hole diameter shall be φ10.375-φ10.355 mm. The ellipticity of the tube hole shall be less than 0.01 mm, the pipe bridge dimension shall be 4.6 mm, conforming to the requirement of the drawing. The paper presents the precautions during machining so as to provide the reference for the similar pipe hole machining in the future. (author)

Air injection evaluation in open steam discharge pipes based on ejector equipment theory

International Nuclear Information System (INIS)

Bigu, M.; Nita, I.; Tenescu, M.

2005-01-01

The paper starts from the finding that the calculation method proposed by ANSI B31.1 for open steam discharge pipes (normative 'ANSI/ASMF B31.1-1980 appendix II Non-Mandatory rules for the design of safety valve installation') shows an air injection in steam system without making a quantitative evaluation of this process of air injection in the exhaust steam. For this it is proposed an assimilation of process with an ejection process in which either steam or air is the ejected fluid. The reason of using opened exhaust systems instead of closed exhaust systems is the fact that expansions and especially shock load from discharge valves and especially in exhaust elbow, are not conducted over the pipe system (ventilation tube). In order to estimate the quantity of air flow which enters through the ejection effect the present paper makes use of gas-gas ejectors. The interest for optimal operating of the system is that the air mixture have a value low in comparison with steam flow (i.e. 2-3% or upmost 5-7%). These percents of mixture lead to properly choosing of the ratio of the two pipe diameters (ventilation tube D/ exhaust elbow d). The results show that optimum ratio is between D/d = 1.10 to 1.15 and in extreme cases 1.20. A lower value of ratio is not acceptable because the pipes come in direct contact when expansion and/or hydraulic hammer occur and stresses from exhaust elbow of safety valve are propagated towards ventilation tube. A higher value of the ratio D/d leads to great air injection in ventilation tube and so to an unjustified large diameter of ventilation tube. It must be mention that the optimal ratio is obtained at sub critical flow of ejected air with Mach number lower then unity, at a static pressure between 0.6 to 1.0 bar in mixture zone of the two fluids. (authors)

Air injection evaluation in open steam discharge pipes based on ejector equipment theory

International Nuclear Information System (INIS)

Bigu, M.; Nita, I.; Tenescu, M.

2005-01-01

Full text: The paper starts from the finding that the calculation method proposed by ANSI B31.1 for open steam discharge pipes (normative 'ANSI/ASMF B31.1-1980 appendix II Non-Mandatory rules for the design of safety valve installation') shows an air injection in steam system without making a quantitative evaluation of this process of air injection in the exhaust steam. For this it is proposed an assimilation of process with an ejection process in which either steam or air is the ejected fluid. The reason of using opened exhaust systems instead of closed exhaust systems is the fact that expansions and especially shock load from discharge valves and especially in exhaust elbow, are not conducted over the pipe system (ventilation tube). In order to estimate the quantity of air flow which enters through the ejection effect the present paper makes use of gas-gas ejectors. The interest for optimal operating of the system is that the air mixture have a value low in comparison with steam flow (i.e. 2-3% or upmost 5-7%). These percents of mixture lead to properly choosing of the ratio of the two pipe diameters (ventilation tube D/ exhaust elbow d). The results show that optimum ratio is between D/d = 1.10 to 1.15 and in extreme cases 1.20. A lower value of ratio is not acceptable because the pipes come in direct contact when expansion and/or hydraulic hammer occur and stresses from exhaust elbow of safety valve are propagated towards ventilation tube. A higher value of the ratio D/d leads to great air injection in ventilation tube and so to an unjustified large diameter of ventilation tube. It must be mention that the optimal ratio is obtained at sub critical flow of ejected air with Mach number lower then unity, at a static pressure between 0.6 to 1.0 bar in mixture zone of the two fluids

Detection of underground water distribution piping system and leakages using ground penetrating radar (GPR)

Science.gov (United States)

Amran, Tengku Sarah Tengku; Ismail, Mohamad Pauzi; Ahmad, Mohamad Ridzuan; Amin, Mohamad Syafiq Mohd; Sani, Suhairy; Masenwat, Noor Azreen; Ismail, Mohd Azmi; Hamid, Shu-Hazri Abdul

2017-01-01

A water pipe is any pipe or tubes designed to transport and deliver water or treated drinking with appropriate quality, quantity and pressure to consumers. The varieties include large diameter main pipes, which supply entire towns, smaller branch lines that supply a street or group of buildings or small diameter pipes located within individual buildings. This distribution system (underground) is used to describe collectively the facilities used to supply water from its source to the point of usage. Therefore, a leaking in the underground water distribution piping system increases the likelihood of safe water leaving the source or treatment facility becoming contaminated before reaching the consumer. Most importantly, leaking can result in wastage of water which is precious natural resources. Furthermore, they create substantial damage to the transportation system and structure within urban and suburban environments. This paper presents a study on the possibility of using ground penetrating radar (GPR) with frequency of 1GHz to detect pipes and leakages in underground water distribution piping system. Series of laboratory experiment was designed to investigate the capability and efficiency of GPR in detecting underground pipes (metal and PVC) and water leakages. The data was divided into two parts: 1. detecting/locating underground water pipe, 2. detecting leakage of underground water pipe. Despite its simplicity, the attained data is proved to generate a satisfactory result indicating GPR is capable and efficient, in which it is able to detect the underground pipe and presence of leak of the underground pipe.

Development and test of a space-reactor-core heat pipe

International Nuclear Information System (INIS)

Merrigan, M.A.; Runyan, J.E.; Martinez, H.E.; Keddy, E.S.

1983-01-01

A heat pipe designed to meet the heat transfer requirements of a 100-kW/sub e/ space nuclear power system has been developed and tested. General design requirements for the device included an operating temperature of 1500 0 K with an evaporator radial flux density of 100 w/cm 2 . The total heat-pipe length of 2 m comprised an evaporator length of 0.3 m, a 1.2-m adiabatic section, and a condenser length of 0.5 m. A four-artery design employing screen arteries and distribution wicks was used with lithium serving as the working fluid. Molybdenum alloys were used for the screen materials and tube shell. Hafnium and zirconium gettering materials were used in connection with a pre-purified distilled lithium charge to ensure internal chemical compatibility. After initial performance verification, the 14.1-mm i.d. heat pipe was operated at 15 kW throughput at 1500 0 K for 100 hours. No performance degradation was observed during the test

Piping structural design for the ITER thermal shield manifold

Energy Technology Data Exchange (ETDEWEB)

Noh, Chang Hyun, E-mail: chnoh@nfri.re.kr [ITER Korea, National Fusion Research Institute, Daejeon 305-333 (Korea, Republic of); Chung, Wooho, E-mail: whchung@nfri.re.kr [ITER Korea, National Fusion Research Institute, Daejeon 305-333 (Korea, Republic of); Nam, Kwanwoo; Kang, Kyoung-O. [ITER Korea, National Fusion Research Institute, Daejeon 305-333 (Korea, Republic of); Bae, Jing Do; Cha, Jong Kook [Korea Marine Equipment Research Institute, Busan 606-806 (Korea, Republic of); Kim, Kyoung-Kyu [Mecha T& S, Jinju-si 660-843 (Korea, Republic of); Hamlyn-Harris, Craig; Hicks, Robby; Her, Namil; Jun, Chang-Hoon [ITER Organization, Route de Vinon-sur-Verdon, CS 90 046, 13067 St. Paul Lez Durance Cedex (France)

2015-10-15

Highlights: • We finalized piping design of ITER thermal shield manifold for procurement. • Support span is determined by stress and deflection limitation. • SQP, which is design optimization method, is used for the pipe design. • Benchmark analysis is performed to verify the analysis software. • Pipe design is verified by structural analyses. - Abstract: The thermal shield (TS) provides the thermal barrier in the ITER tokamak to minimize heat load transferred by thermal radiation from the hot components to the superconducting magnets operating at 4.2 K. The TS is actively cooled by 80 K pressurized helium gas which flows from the cold valve box to the cooling tubes on the TS panels via manifold piping. This paper describes the manifold piping design and analysis for the ITER thermal shield. First, maximum allowable span for the manifold support is calculated based on the simple beam theory. In order to accommodate the thermal contraction in the manifold feeder, a contraction loop is designed and applied. Sequential Quadratic Programming (SQP) method is used to determine the optimized dimensions of the contraction loop to ensure adequate flexibility of manifold pipe. Global structural behavior of the manifold is investigated when the thermal movement of the redundant (un-cooled) pipe is large.

Experimental study of thermal performance of heat pipe with axial trapezoidal grooves

International Nuclear Information System (INIS)

Suh, Jeong Se; Lee, Woon

2003-01-01

Analysis and experiment are performed to investigate the thermal performance of a heat pipe with axial grooves. The heat pipe was designed in a 6.5 mm I.D., 17 axial trapezoidal grooves, 1000 mm long tube of aluminium, and ammonia as working fluid. A mathematical equations for heat pipe with axial grooves is formulated to obtain the capillary limitation on heat transport rate in a steady state. As a result, heat transport factor of heat pipe has the maximum at the operating temperature of 293K in 0m elevation. As the elevation of heat pipe increases, the heat transport factor of the heat pipe is reduced markedly, comparing with that of horizontal elevation of the heat pipe. It may be considered that such behavior of heat pipe is caused by the working fluid swarmed back to the condenser port due to gravity force and supercooled by a coolant of heat exchanger. Analytical results of heat transport factor are in a good agreement with those of experiment

Numerical simulation of double-pipe condensers and evaporators

Energy Technology Data Exchange (ETDEWEB)

Garcia-Valladares, O. [Universidad Nacional Autonoma de Mexico, Morelos (Mexico). Centro de Investigacion en Energia; Perez-Segarra, C.D.; Rigola, J. [Universitat Politecnica de Catalunya, Terrassa (Spain). Centre Tecnologic de Transferencia de Calor, Lab. de Termotecnia i Energetica

2004-09-01

A detailed one-dimensional steady and transient numerical simulation of the thermal and fluid-dynamic behaviour of double-pipe heat exchangers (evaporators and condensers) has been carried out. The governing equations (continuity, momentum and energy) inside the internal tube and the annulus, together with the energy equation in the internal tube wall, external tube wall and insulation, are solved iteratively in a segregated manner. The discretized governing equations in the zones with fluid flow are efficiently coupled using an implicit step by step method. This formulation requires the use of empirical correlations for the evaluation of convective heat transfer, shear stress and void fraction. An implicit central difference numerical scheme and a line-by-line solver was used in the internal and external tube walls and insulation. A special treatment has been implemented in order to consider transitions (single-phase/two-phase, dry-out,...). All the flow variables (enthalpies, temperatures, pressures, mass fractions, velocities, heat fluxes,...) together with the thermophysical properties are evaluated at each point of the grid in which the domain is discretized. Different numerical aspects and comparisons with analytical and experimental results are presented in order to verify and validate the model. (author)

Performance Study of Solar Heat Pipe with Different Working Fluids and Fill Ratios

Science.gov (United States)

Harikrishnan, S. S.; Kotebavi, Vinod

2016-09-01

This paper elaborates on the testing of solar heat pipes using different working fluids, fill ratios and tilt angles. Methanol, Acetone and water are used as working fluids, with fill ratios 25%, 50%, 75% and 100%. Experiments were carried out at 600 and 350 inclinations. Heat pipe condenser section is placed inside a water basin containing 200ml of water. The evaporator section is exposed to sunlight where the working fluid gets heated and it becomes vapour and moves towards the condenser section. In the condenser section the heat is given to the water in the basin and the vapour becomes liquid and comes back to the evaporator section due to gravitational force. Two modes of experiments are carried out: 1) using a parabolic collector and 2) using heat pipe with evacuated tubes. On comparative study, optimum fill ratio is been found to be 25% in every case and acetone exhibited slightly more efficiency than methanol and water. As far as the heat pipe orientation is concerned, 600 inclination of the heat pipe showed better performance than 350

Computer program TMOC for calculating of pressure transients in fluid filled piping networks

International Nuclear Information System (INIS)

Siikonen, T.

1978-01-01

The propagation of a pressure wave in fluid filles tubes is significantly affected by the pipe wall motion and vice versa. A computer code TMOC (Transients by the Method of Characteristics) is being developed for the analysis of the coupled fluid and pipe wall transients. Because of the structural feedback, the pressure can be calculated more accurately than in the programs commonly used. (author)

Advanced evacuated tube collectors

Science.gov (United States)

Schertz, W. W.; Hull, J. R.; Winston, R.; Ogallagher, J.

1985-04-01

The essence of the design concept for these new collectors is the integration of moderate levels of nonimaging concentration inside the evacuated tube itself. This permanently protects the reflection surfaces and allows the use of highly reflecting front surface mirrors with reflectances greater than 95%. Previous fabrication and long term testing of a proof-of-concept prototype has established the technical success of the concept. Present work is directed toward the development of a manufacturable unit that will be suitable for the widest possible range of applications. Design alternatives include scaling up the original prototype's tube diameter from 5 cm to 10 cm, using an internal shaped metal concentrating reflector, using a variety of profile shapes to minimize so-called gap losses and accommodate both single ended and double-ended flow geometries, and allowing the use of heat pipes for the absorber tube.

Gas propagation following a sudden loss of vacuum in a pipe cooled by He I and He II.

Science.gov (United States)

Garceau, N.; Guo, W.; Dodamead, T.

2017-12-01

Many cryogenic systems around the world are concerned with the sudden catastrophic loss of vacuum for cost, preventative damage, safety or other reasons. The experiments in this paper were designed to simulate the sudden vacuum break in the beam-line pipe of a liquid helium cooled superconducting particle accelerator. This paper expands previous research conducted at the National High Magnetic Field Laboratory and evaluates the differences between normal helium (He I) and superfluid helium (He II). For the experiments, a straight pipe and was evacuated and immersed in liquid helium at 4.2 K and below 2.17 K. Vacuum loss was simulated by opening a solenoid valve on a buffer tank filled nitrogen gas. Gas front arrival was observed by a temperature rise of the tube. Preliminary results suggested that the speed of the gas front through the experiment decreased exponentially along the tube for both normal liquid helium and super-fluid helium. The system was modified to a helical pipe system to increase propagation length. Testing and analysis on these two systems revealed there was minor difference between He I and He II despite the difference between the two distinct helium phases heat transfer mechanisms: convection vs thermal counterflow. Furthermore, the results indicated that the temperature of the tube wall above the LHe bath also plays a significant role in the initial front propagation. More systematic measurements are planned in with the helical tube system to further verify the results.

Enhanced heat transfer performances of molten salt receiver with spirally grooved pipe

International Nuclear Information System (INIS)

Lu, Jianfeng; Ding, Jing; Yu, Tao; Shen, Xiangyang

2015-01-01

The enhanced heat transfer performances of solar receiver with spirally grooved pipe were theoretically investigated. The physical model of heat absorption process was proposed using the general heat transfer correlation of molten salt in smooth and spirally grooved pipe. According to the calculation results, the convective heat transfer inside the receiver can remarkably enhance the heat absorption process, and the absorption efficiency increased with the flow velocity and groove height, while the wall temperature dropped. As the groove height increased, the heat losses of convection and radiation dropped with the decrease of wall temperature, and the average absorption efficiency of the heat receiver can be increased. Compared with the heat receiver with smooth pipe, the heat absorption efficiency of heat receiver with spirally grooved pipe e/d = 0.0475 can rise for 0.7%, and the maximum bulk fluid temperature can be increased for 31.1 °C. As a conclusion, spirally grooved pipe can be a very effective way for heat absorption enhancement of solar receiver, and it can also increase the operating temperature of molten salt. - Highlights: • Spirally grooved tube is a very effective way for solar receiver enhancement. • Heat absorption model of receiver is proposed with general heat transfer correlation. • Spirally groove tube increases absorption efficiency and reduces wall temperature. • Operating temperature of molten salt remarkably increases with groove height. • Heat absorption performance is promoted for first and second thermodynamics laws

Hybrid heat pipe based passive cooling device for spent nuclear fuel dry storage cask

International Nuclear Information System (INIS)

Jeong, Yeong Shin; Bang, In Cheol

2016-01-01

Highlights: • Hybrid heat pipe was presented as a passive cooling device for dry storage cask of SNF. • A method to utilize waste heat from spent fuel was suggested using hybrid heat pipe. • CFD analysis was performed to evaluate the thermal performance of hybrid heat pipe. • Hybrid heat pipe can increase safety margin and storage capacity of the dry storage cask. - Abstract: Conventional dry storage facilities for spent nuclear fuel (SNF) were designed to remove decay heat through the natural convection of air, but this method has limited cooling capacity and a possible re-criticality accident in case of flooding. To enhance the safety and capacity of dry storage cask of SNF, hybrid heat pipe-based passive cooling device was suggested. Heat pipe is an excellent passive heat transfer device using the principles of both conduction and phase change of the working fluid. The heat pipe containing neutron absorber material, the so-called hybrid heat pipe, is expected to prevent the re-criticality accidents of SNF and to increase the safety margin during interim and long term storage period. Moreover, a hybrid heat pipe with thermoelectric module, a Stirling engine and a phase change material tank can be used for utilization of the waste heat as heat-transfer medium. Located at the guide tube or instrumentation tube, hybrid heat pipe can remove decay heat from inside the sealed metal cask to outside, decreasing fuel rod temperature. In this paper, a 2-step analysis was performed using computational fluid dynamics code to evaluate the heat and fluid flow inside a cask, which consisted of a single spent fuel assembly simulation and a full-scope dry cask simulation. For a normal dry storage cask, the maximum fuel temperature is 290.0 °C. With hybrid heat pipe cooling, the temperature decreased to 261.6 °C with application of one hybrid heat pipe per assembly, and to 195.1 °C with the application of five hybrid heat pipes per assembly. Therefore, a dry

Quality Determination of Pipe-Borne Water in Sokoto Metropolis ...

African Journals Online (AJOL)

The quality of the pipe-borne water supplied to Sokoto metropolis was determined in this study. The total bacterial count was carried out using surface plating method of inoculation. The coliforms were enumerated using multiple tube fermentation technique (Most Probable Number Method). Some physicochemical ...

Method of repairing pressure tube type reactors

International Nuclear Information System (INIS)

Asada, Takashi.

1983-01-01

Purpose: To enable to re-start the reactor operation in a short time, upon occurrence of failures in a pressure tube, as well as directly examine the cause for the failures in the pressure tube. Method: The pressure tube reactor main body comprises a calandria tank of a briquette form, pressure tubes, fuel assemblies and an iron-water shielding body. If failure is resulted to a pressure tube, the reactor operation is at first shutdown and nuclear fuel assemblies are extracted to withdraw from the pressure tube. Then, to an inlet pipe way and an outlet pipeway connected to the failed pressure tube, are attached plugs by means of welding or the like at the appropriate position where the radiation exposure dose is lower and the repairing work can be performed with ease. The pressure tube is disconnected to withdraw from the inlet pipeway and the outlet pipeway and, instead, radiation shielding plug tube is inserted and shield cooling device is actuated if required, wherein the reactor is actuated to re-start the operation. (Yoshino, Y.)

Nuclear piping and pipe support design and operability relating to loadings and small bore piping

International Nuclear Information System (INIS)

Stout, D.H.; Tubbs, J.M.; Callaway, W.O.; Tang, H.T.; Van Duyne, D.A.

1994-01-01

The present nuclear piping system design practices for loadings, multiple support design and small bore piping evaluation are overly conservative. The paper discusses the results developed for realistic definitions of loadings and loading combinations with methodology for combining loads under various conditions for supports and multiple support design. The paper also discusses a simplified method developed for performing deadweight and thermal evaluations of small bore piping systems. Although the simplified method is oriented towards the qualification of piping in older plants, this approach is applicable to plants designed to any edition of the ASME Section III or B31.1 piping codes

Device for the automatic X-ray testing of welded joints of pipes

International Nuclear Information System (INIS)

Ries, K.; Hannoschieck, K.; Rozic, K.M.; Basler, G.

1979-01-01

The notification flows of the tested pipes determined by the ultrasonic inspection are transmitted to the X-ray film automatic charger in the X-ray test room. The roll table for the pipes from the ultrasonic inspection to the X-ray test room is provided with an arrangement for weld detection and tube lathe, so that the X-ray films can be set on the corresponding spot by means of a cantilever. (RW) [de

Simulation studies on Tube End Expansion of AA2014 Alloy Tubes

Science.gov (United States)

Venugopal, L.; Prasad, N. E. C.; Geeta Krishna, P.; Praveen, L.

2018-03-01

End forming is defined as forming the end of tubular forms either by inverting the tube or by expanding it. It finds application in many fields such as in automotive and aerospace sectors as power transmission elements, fuel lines, exhaust pipes etc. The main aim of the present work is to expand the AA2014 alloy tubes with different die sets without any fracture. Deform 2D software was used for performing simulations on expanding the tubes with different die set (punch) values having differed forming angles (α = 15°, 30° and 45°) and expansion ratios (rp/r0 = 1.39, 1.53 and 1.67). Experiments were also conducted and the results correlate with the simulation results. The results shows that for the punch having less cone angle (α) values the linear displacement is more rather than higher cone angles. But in the case of higher cone angles the radial displacement is more than the linear displacement.

Development of Evaluation Technology of the Integrity of HWR Pressure Tubes

International Nuclear Information System (INIS)

Kim, Y. S.; Jeong, Y. M.; Ahn, S. B.

2005-03-01

Major degradation of the feeder pipe is the thinning due to the flow accelerated corrosion and the cracking in the bent region due to the stress corrosion cracking. The feeder pipe in a PHWR is a pipe to supply the coolant to the pressure tube and the heated coolant to the steam generator for power generation. Approximately 380 pipes are installed on the inlet side and outlet side each with two bent regions in the 600 MW-class PHWR. After a leakage in the bent region of the feeder pipe, it is required to examine all the pipes in order to ensure the integrity of the pressure boundaries. It is not easy, however, to examine all the pipes with the conventional ultrasonic method, because of a high dose of radiation exposure and a limited accessibility to the pipe. In order to get rid of the limited accessibility, the ultrasonic guided wave method are developed for detection and evaluation of the cracks in the feeder pipe. The dispersion mode analysis was performed for the development of long-range guided wave inspection for the feeder pipe. An analytical approach for the straight pipe as well as numerical approach for the bent pipe with 2-D FFT were accomplished. A computer program for the calculation of the dispersion curves and wave structures was developed. Based on the dispersion curves and wave structure of the feeder pipe, candidates for the optimal parameters on the frequencies and vibration modes were selected. A time-frequency analysis methodology was developed for the mode identification of received ultrasonic signal. A high power tone-burst ultrasonic system has been setup for the generation of guided waves. Various artificial notches were fabricated on the bent feeder pipes for the experiment on the flaw detection. Considering the results of dispersion analysis and field condition, the torsional vibration mode, T(0,1) is selected for the first choice. An array of electromagnetic acoustic transducers (EMAT) was designed and fabricated for the generation of T

Development of Evaluation Technology of the Integrity of HWR Pressure Tubes

Energy Technology Data Exchange (ETDEWEB)

Kim, Y S; Jeong, Y M; Ahn, S B [and others

2005-03-15

Major degradation of the feeder pipe is the thinning due to the flow accelerated corrosion and the cracking in the bent region due to the stress corrosion cracking. The feeder pipe in a PHWR is a pipe to supply the coolant to the pressure tube and the heated coolant to the steam generator for power generation. Approximately 380 pipes are installed on the inlet side and outlet side each with two bent regions in the 600 MW-class PHWR. After a leakage in the bent region of the feeder pipe, it is required to examine all the pipes in order to ensure the integrity of the pressure boundaries. It is not easy, however, to examine all the pipes with the conventional ultrasonic method, because of a high dose of radiation exposure and a limited accessibility to the pipe. In order to get rid of the limited accessibility, the ultrasonic guided wave method are developed for detection and evaluation of the cracks in the feeder pipe. The dispersion mode analysis was performed for the development of long-range guided wave inspection for the feeder pipe. An analytical approach for the straight pipe as well as numerical approach for the bent pipe with 2-D FFT were accomplished. A computer program for the calculation of the dispersion curves and wave structures was developed. Based on the dispersion curves and wave structure of the feeder pipe, candidates for the optimal parameters on the frequencies and vibration modes were selected. A time-frequency analysis methodology was developed for the mode identification of received ultrasonic signal. A high power tone-burst ultrasonic system has been setup for the generation of guided waves. Various artificial notches were fabricated on the bent feeder pipes for the experiment on the flaw detection. Considering the results of dispersion analysis and field condition, the torsional vibration mode, T(0,1) is selected for the first choice. An array of electromagnetic acoustic transducers (EMAT) was designed and fabricated for the generation of T

Three-dimensional numerical modeling of turbulent single-phase and two-phase flow in curved pipes

International Nuclear Information System (INIS)

Xin, R.C.; Dong, Z.F.; Ebadian, M.A.

1996-01-01

In this study, three-dimensional single-phase and two-phase flows in curved pipes have been investigated numerically. Two different pipe configurations were computed. When the results of the single-phase flow simulation were compared with the experimental data, a fairly good agreement was achieved. A flow-developing process has been suggested in single-phase flow, in which the turbulence is stronger near the outer tube wall than near the inner tube wall. For two-phase flow, the Eulerian multiphase model was used to simulate the phase distribution of a three-dimensional gas-liquid bubble flow in curved pipe. The RNG/κ-ε turbulence model was used to determine the turbulence field. An inlet gas void fraction of 5 percent was simulated. The gas phase effects on the liquid phase flow velocity have been examined by comparing the results of single-phase flow and two-phase flow. The findings show that for the downward flow in the U bend, the gas concentrates at the inner portion of the cross section at φ = π/18 - π/6 in most cases. The results of the phase distribution simulation are compared to experimental observations qualitatively and topologically

27 CFR 41.72a - Notice for pipe tobacco.

Science.gov (United States)

2010-04-01

... 27 Alcohol, Tobacco Products and Firearms 2 2010-04-01 2010-04-01 false Notice for pipe tobacco. 41.72a Section 41.72a Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE BUREAU, DEPARTMENT OF THE TREASURY (CONTINUED) TOBACCO IMPORTATION OF TOBACCO PRODUCTS, CIGARETTE PAPERS AND TUBES...

Determination of the acoustic damping characteristics of an annular tail pipe

OpenAIRE

Boonen, Rene; Sas, Paul; Van den Bulck, Eric

2010-01-01

A damping device, consisting of an annular tail-pipe, has been developed. It is applicable in situations wherein acoustic damping is required in combination with low flow resistance. Examples are ventilation systems, turbo- engines, intake and exhaust systems for internal combustion engines. The device consists of a central tube surrounded by a narrow slit. The central tube has an acoustic mass which impedance increases with frequency. When the frequency has been increased sufficiently, a con...

Remote field eddy current testing of ferromagnetic tubes

International Nuclear Information System (INIS)

David, B.

1990-01-01

In order to test ferromagnetic tubes using internal probes, Intercontrole and the CEA have carried out theoretical and experimental works and developed a method to adapt the Remote Field Eddy Current technique which has been known and used for 30 years now. This document briefly recalls the basic principles of the Remote Field Eddy Current technique, the various steps of the works carried out and mainly describes examples of field inspection of ferromagnetic tubes and pipes [fr

Use of CATHENA to model calandria-tube/moderator heat transfer after pressure-tube/calandria-tube ballooning contact

International Nuclear Information System (INIS)

Fan, H.Z.; Bilanovic, Z.; Nitheanandan, T.

2004-01-01

A study was performed to assess the effect of the calandria-tube/moderator heat transfer after pressure-tube/calandria tube ballooning contact using CATHENA. Results of this study indicated that the analytical tool, CATHENA, can be applied for pool boiling heat transfer on the external surface of a large diameter tube, such as the calandria tube used in CANDU reactors. The methodology in such CANDU-generic study can be used to simulate the tube surface with multiple boiling regimes and to assess the benefits of closely coupling thermalhydraulics modelling and fuel/fuel channel behaviour modelling. CATHENA (Canadian Algorithm for THErmalhydraulic Network Analysis) is a one-dimensional, two-fluid thermalhydraulic simulation code designed by AECL to analyse two-phase flow and heat transfer in piping networks. The detailed heat transfer package in CATHENA allows a connection to be established from the multiple solid surfaces of tubes to the surrounding large amount of moderator water, which acts as a heat sink during a postulated loss of coolant event. The generalized heat transfer package within CATHENA allows the tube walls to be divided into several layers in the radial direction and several sectors in the circumferential direction, to account for heat transfer conditions in these two directions. The CATHENA code with the generalized heat transfer package is capable of capturing key pool-boiling phenomena such as nucleate, transition and film boiling heat transfer as well as an ability to model the rewet phenomenon to some extent. A CATHENA input model was generated and used in simulations of selected contact boiling experiment test cases. The transient wall temperatures have been calculated in different portions of the calandria tube. By using this model an adequate agreement was achieved between CATHENA calculation and experimental measurement The CATHENA code enables one to investigate the transient and local thermal-mechanical behaviour of the calandria tube

76 FR 77770 - Certain Circular Welded Non-Alloy Steel Pipe From Mexico: Final Results of Antidumping Duty...

Science.gov (United States)

2011-12-14

... previous review or the original less-than-fair-value (LTFV) investigation, the cash deposit rate will... Determination of Sales at Less Than Fair Value: Circular Welded Non-Alloy Steel Pipe From Mexico, 57 FR 42953... structural pipe tubing used for framing and support members for reconstruction or load-bearing purposes in...

Automated numerical simulation of cracked plates, pipes and elbows

International Nuclear Information System (INIS)

Reddy, Babu; Sreehari Kumar, B.; Bhate, S.R.; Kushwaha, H.S.

2008-01-01

In the nuclear industry, piping components are one of the key elements participating in its operation. Integrity of structural tubes and pipes plays a major role in nuclear power plants. The ideal procedure to ensure this aspect would be to conduct experimental studies on pilot/test specimens. However, it may not always be feasible to carry out the experimental investigation, as it requires pre-requisite infrastructure which may not be economically viable. This makes it imperative to conduct numerical simulations of the same particularly in the study of presence of cracks in the critical components. While performing the effect of cracks, the quality of the finite element mesh nearer to the crack tip plays a critical role while estimating J-integral value. The designer is often familiar with design methodology only and he obviously requires a convenient and reliable numerical tool to model and perform the analysis. In this context, an effort has been made in NISA, the general purpose finite element software, to automate the generation of FE meshes for a set of pre-defined components with different crack configurations. To simplify the procedure of FE mesh generation, analysis, and post processing, a graphical user interface (GUI) has been developed accordingly. This paper discusses the automated numerical simulation of plates and pipes with different crack configurations. This simulation software is also designed to help parametric study of cracked pipes. (author)

27 CFR 45.45a - Notice for pipe tobacco.

Science.gov (United States)

2010-04-01

... 27 Alcohol, Tobacco Products and Firearms 2 2010-04-01 2010-04-01 false Notice for pipe tobacco. 45.45a Section 45.45a Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE BUREAU, DEPARTMENT OF THE TREASURY (CONTINUED) TOBACCO REMOVAL OF TOBACCO PRODUCTS AND CIGARETTE PAPERS AND TUBES...

Standard specification for Nickel-Chromium-Iron alloys (UNS N06600, N06601, N06603, N06690, N06693, N06025, N06045, and N06696), Nikel-Chromium-Cobalt-Molybdenum alloy (UNS N06617), and Nickel-Iron-Chromium-Tungsten alloy (UNS N06674) seamless pipe and tube

CERN Document Server

American Society for Testing and Materials. Philadelphia

2011-01-01

Standard specification for Nickel-Chromium-Iron alloys (UNS N06600, N06601, N06603, N06690, N06693, N06025, N06045, and N06696), Nikel-Chromium-Cobalt-Molybdenum alloy (UNS N06617), and Nickel-Iron-Chromium-Tungsten alloy (UNS N06674) seamless pipe and tube

Fabrication and performance evaluation of flexible heat pipes for potential thermal control of foldable electronics

International Nuclear Information System (INIS)

Yang, Chao; Chang, Chao; Song, Chengyi; Shang, Wen; Wu, Jianbo; Tao, Peng; Deng, Tao

2016-01-01

Highlights: • A flexible and high-performance heat pipe is fabricated. • Bending effect on thermal performance of flexible heat pipes is evaluated. • Theoretical analysis is carried out to reveal the change of thermal resistance with bending. • Thermal control of foldable electronics with flexible heat pipes is demonstrated. - Abstract: In this work, we report the fabrication and thermal performance evaluation of flexible heat pipes prepared by using a fluororubber tube as the connector in the adiabatic section and using strong base treated hydrophilic copper meshes as the wick structure. Deionized water was chosen as working fluid and three different filling ratios (10%, 20%, and 30%) of working fluid were loaded into the heat pipe to investigate its impact on thermal performance. The fabricated heat pipes can be easily bended from 0"o to 180"o in the horizontal operation mode and demonstrated consistently low thermal resistances after repeated bending. It was found that with optimized amount of working fluid, the thermal resistance of flexible heat pipes increased with larger bending angles. Theoretical analysis reveals that bending disturbs the normal vapor flow from evaporator to condenser in the heat pipe, thus leads to increased liquid–vapor interfacial thermal resistance in the evaporator section. The flexible heat pipes have been successfully applied for thermal control of foldable electronic devices showing superior uniform heat-transfer performance.

First Research Coordination Meeting on Prediction of Axial and Radial Creep in HWR Pressure Tubes. Presentations

International Nuclear Information System (INIS)

2013-01-01

Pressure tube deformation is a critical aging issue in operating Heavy Water Reactors (HWRs). According to the service year, horizontal pressure tubes have three kinds of deformation: diametral creep leading to the flow bypass and the penalty to critical heat flux for fuel rods, longitudinal creep leading to the interference of feeder pipes and/or with fuelling machine, and sagging leading to the interference with in-core components and potential contact between the pressure tube and calandria tube. The CRP scope includes the establishment of a database for pressure tube deformation, microstructure characterization of pressure tube materials collected from HWRs currently operating in Member States and development of a prediction model for pressure tube deformation

Heat resistant wire and cable and heat shrinkable tubes

Energy Technology Data Exchange (ETDEWEB)

Ueno, Keiji [Sumitomo Electric Industries Ltd. (Japan)

1994-12-31

Radiation processes have been used in industrial fields (e.g. wire and cable, heat shrinkable tubes) for about 30 years. In Japan, 60 electron beam accelerators were used in R and D, 54 in wire and cable, 24 in tire rubber, 16 in paint curing, 14 in PE foam and 9 accelerators were used in heat shrinkable tubes in 1993. Many properties (e.g. solder resistance, thermal deformation, and solven resistance) of wire and cable are improved by using radiation processes, and many kinds of radiation crosslinked wire and cable are used in the consumer market (TV sets, VTR`s, audio disc players, etc.), automobiles (automobile wire harnesses, fusible link wires, sensor cables etc.), and the industrial market (computer cables, cables for keyboards, coaxial cables, etc.). Another important industrial application of E{beta} radiation process is heat shrinkable tubes. Heat shinkable tubes, heated by a hot gun, shrink 1/2 {approx} 1/3 of their inner diameters. Heat shrinkable tubes are used for covers of distributing line terminals, joint covers of telecommunication lines, protection of fuel pipe lines and so on. In this seminar, actual applications and characteristic properties of radiation crosslinked materials are presented.

Heat resistant wire and cable and heat shrinkable tubes

International Nuclear Information System (INIS)

Keiji Ueno

1994-01-01

Radiation processes have been used in industrial fields (e.g. wire and cable, heat shrinkable tubes) for about 30 years. In Japan, 60 electron beam accelerators were used in R and D, 54 in wire and cable, 24 in tire rubber, 16 in paint curing, 14 in PE foam and 9 accelerators were used in heat shrinkable tubes in 1993. Many properties (e.g. solder resistance, thermal deformation, and solven resistance) of wire and cable are improved by using radiation processes, and many kinds of radiation crosslinked wire and cable are used in the consumer market (TV sets, VTR's, audio disc players, etc.), automobiles (automobile wire harnesses, fusible link wires, sensor cables etc.), and the industrial market (computer cables, cables for keyboards, coaxial cables, etc.). Another important industrial application of Eβ radiation process is heat shrinkable tubes. Heat shinkable tubes, heated by a hot gun, shrink 1/2 ∼ 1/3 of their inner diameters. Heat shrinkable tubes are used for covers of distributing line terminals, joint covers of telecommunication lines, protection of fuel pipe lines and so on. In this seminar, actual applications and characteristic properties of radiation crosslinked materials are presented

Steam generator with U-tube bank arranged within an oblong pressure vessel

International Nuclear Information System (INIS)

Beckmann, G.; Fritz, K.

1976-01-01

This steam generator equipped with a U-tube bundle differs substantially from standard types because of its operational condition. The boiler is at a tilt of 45 0 , the piping base, the inlet, and the outlet for the primary medium are arranged at the top. This improves the heat flow of the secondary medium within the boiler. The steam room placed near the piping base is enlarged on the hot side of the U-tube bundle due to the tilt of the water level, allowing drying and overheating of the steam without additional mounting of water separators and special overheaters. The additional space obtained by this construction is estimated at 6%. (FW) [de

Heat transfer pipe shielding device for heat exchanger

International Nuclear Information System (INIS)

Hanawa, Jun.

1991-01-01

The front face and the rear face of a frame that surrounds the circumference of the water chamber body of a multi-tube heat exchanger are covered by a rotational shielding plate. A slit is radially formed to the shielding plate for the insertion of a probe or cleaner to the heat transfer pipe and a deflector is disposed on the side opposite to the slit. The end of the heat transfer pipe to be inspected is exposed to the outer side by way of the slit by the rotation of the shielding plate, and the probe or cleaner is inserted in the heat transfer pipe to conduct an eddy current injury monitoring test or cleaning. The inside of the water chamber and the heat transfer pipe is exhausted by a ventilation nozzle disposed to the frame. Accordingly, a shielding effect upon inspection and cleaning can be obtained and, in addition, inspection and exhaustion at the cleaning position can be conducted easily. Since the operation for attachment and detachment is easy, the effect of reducing radiation dose per unit can be obtained by the shortening of the operation time. (N.H.)

Pipe inspection using the BTX-II. Innovative technology summary report

International Nuclear Information System (INIS)

1999-05-01

The US Department of Energy (DOE) continually seeks safer and more cost-effective remediation technologies for use in the decontamination and decommissioning (D and D) of nuclear facilities. In several of the buildings at the Fernald Site, there is piping that was used to transport process materials. As the demolition of these buildings occur, disposal of this piping has become a costly issue. Currently, all process piping is cut into ten-foot or less sections, the ends of the piping are wrapped and taped to prevent the release of any potential contaminants into the air, and the piping is placed in roll off boxes for eventual repackaging and shipment to the Nevada Test Site (NTS) for disposal. Alternatives that allow for the onsite disposal of process piping are greatly desired due to the potential for dramatic savings in current offsite disposal costs. No means is currently employed to allow for the adequate inspection of the interior of piping, and consequently, process piping has been assumed to be internally contaminated and thus routinely disposed of at NTS. The BTX-II system incorporates a high-resolution micro color camera with lightheads, cabling, a monitor, and a video recorder. The complete probe is capable of inspecting pipes with an internal diameter (ID) as small as 1.4 inches. By using readily interchangeable lightheads, the same system is capable of inspecting piping up to 24 inches in ID. The original development of the BTX system was for inspection of boiler tubes and small diameter pipes for build-up, pitting, and corrosion. However, the system is well suited for inspecting the interior of most types of piping and other small, confined areas. The report describes the technology, its performance, uses, cost, regulatory and policy issues, and lessons learned

Pipe inspection using the BTX-II. Innovative technology summary report

Energy Technology Data Exchange (ETDEWEB)

NONE

1999-05-01

The US Department of Energy (DOE) continually seeks safer and more cost-effective remediation technologies for use in the decontamination and decommissioning (D and D) of nuclear facilities. In several of the buildings at the Fernald Site, there is piping that was used to transport process materials. As the demolition of these buildings occur, disposal of this piping has become a costly issue. Currently, all process piping is cut into ten-foot or less sections, the ends of the piping are wrapped and taped to prevent the release of any potential contaminants into the air, and the piping is placed in roll off boxes for eventual repackaging and shipment to the Nevada Test Site (NTS) for disposal. Alternatives that allow for the onsite disposal of process piping are greatly desired due to the potential for dramatic savings in current offsite disposal costs. No means is currently employed to allow for the adequate inspection of the interior of piping, and consequently, process piping has been assumed to be internally contaminated and thus routinely disposed of at NTS. The BTX-II system incorporates a high-resolution micro color camera with lightheads, cabling, a monitor, and a video recorder. The complete probe is capable of inspecting pipes with an internal diameter (ID) as small as 1.4 inches. By using readily interchangeable lightheads, the same system is capable of inspecting piping up to 24 inches in ID. The original development of the BTX system was for inspection of boiler tubes and small diameter pipes for build-up, pitting, and corrosion. However, the system is well suited for inspecting the interior of most types of piping and other small, confined areas. The report describes the technology, its performance, uses, cost, regulatory and policy issues, and lessons learned.

Direct solar steam generation inside evacuated tube absorber

Directory of Open Access Journals (Sweden)

Khaled M. Bataineh

2016-12-01

Full Text Available Direct steam generation by solar radiation falling on absorber tube is studied in this paper. A system of single pipe covered by glass material in which the subcooled undergoes heating and evaporation process is analyzed. Mathematical equations are derived based on energy, momentum and mass balances for system components. A Matlab code is built to simulate the flow of water inside the absorber tube and determine properties of water along the pipe. Widely accepted empirical correlations and mathematical models of turbulent flow, pressure drop for single and multiphase flow, and heat transfer are used in the simulation. The influences of major parameters on the system performance are investigated. The pressure profiles obtained by present numerical solution for each operation condition (3 and 10 MPa matches very well experimental data from the DISS system of Plataforma Solar de Almería. Furthermore, results obtained by simulation model for pressure profiles are closer to the experimental data than those predicted by already existed other numerical model.

Theory and design of heat exchanger : Double pipe and heat exchanger in abnormal condition

International Nuclear Information System (INIS)

Min, Ui Dong

1996-02-01

This book introduces theory and design of heat exchanger, which includes HTRI program, multiple tube heat exchanger external heating, theory of heat transfer, basis of design of heat exchanger, two-phase flow, condensation, boiling, material of heat exchanger, double pipe heat exchanger like hand calculation, heat exchanger in abnormal condition such as Jackets Vessel, and Coiled Vessel, design and summary of steam tracing.

The precision cutting control research of automotive stainless steel thin wall pipe

Directory of Open Access Journals (Sweden)

Jin Lihong

2015-01-01

Full Text Available Stainless steel thin-walled tube are widely used in automobile industry at present, but as a result of thin wall pipe is poor strength and poor rigidity,which lead to deformation, shaped differencer and other problems in the process, it is hard to ensure the processing quality of parts. This paper proposes a method of thin stainless steel thin wall pipe cutting process in vehicle, greatly improved the problems and technical difficulties in the traditional process, the main research is about the cutting system and the hydraulic fixture design, obtained under low cost circumstances, it can realize high precision stainless steel pipes, high degree of automation to automatic cutting,simplified operation steps at the same time, increased the applicability of the system, provided a kind of advanced stainless steel thin wall pipe cutting device for the small and medium-sized enterprises.

Track chambers based on precision drift tubes housed inside 30 mm mylar pipe

International Nuclear Information System (INIS)

Borisov, A; Bozhko, N; Fakhrutdinov, R; Kozhin, A; Leontiev, B; Levin, A

2014-01-01

We describe drift chambers consisting of 3 layers of 30 mm (OD) drift tubes made of double sided aluminized mylar film with thickness 0.125 mm. A single drift tube is self-supported structure withstanding 350 g tension of 50 microns sense wire located in the tube center with 10 microns precision with respect to end-plug outer surface. Such tubes allow to create drift chambers with small amount of material, construction of such chambers doesn't require hard frames. Twenty six chambers with working area from 0.8 × 1.0 to 2.5 × 2.0 m 2 including 4440 tubes have been manufactured for experiments at 70-GeV proton accelerator at IHEP(Protvino)

Track chambers based on precision drift tubes housed inside 30 mm mylar pipe

Science.gov (United States)

Borisov, A.; Bozhko, N.; Fakhrutdinov, R.; Kozhin, A.; Leontiev, B.; Levin, A.

2014-06-01

We describe drift chambers consisting of 3 layers of 30 mm (OD) drift tubes made of double sided aluminized mylar film with thickness 0.125 mm. A single drift tube is self-supported structure withstanding 350 g tension of 50 microns sense wire located in the tube center with 10 microns precision with respect to end-plug outer surface. Such tubes allow to create drift chambers with small amount of material, construction of such chambers doesn't require hard frames. Twenty six chambers with working area from 0.8 × 1.0 to 2.5 × 2.0 m2 including 4440 tubes have been manufactured for experiments at 70-GeV proton accelerator at IHEP(Protvino).

Sensitivity of the magnetization curves of different austenitic stainless tube and pipe steels to mechanical fatigue

International Nuclear Information System (INIS)

Niffenegger, M.; Leber, H.J.

2008-01-01

In meta-stable austenitic stainless steels, fatigue is accompanied by a partial strain-induced transformation of paramagnetic austenite to ferromagnetic martensite [G.B. Olsen, M. Cohen, Kinetics of strain induced martensite nucleation, Metall. Trans. 6 (1975) 791-795]. The associated changes of magnetic properties as the eddy current impedance, magnetic permeability or the remanence field may serve as an indication for the degree of fatigue and therefore the remaining lifetime of a component, even though the exact causal relationship between martensite formation and fatigue is not fully understood. However, measuring these properties by magnetic methods may be limited by the low affinity for strain-induced martensite formation. Thus other methods have to be found which are able to detect very small changes of ferromagnetic contents. With this aim the influence of cyclic strain loading on the magnetization curves of the austenitic stainless tube and pipe steels TP 321, 347, 304L and 316L is analysed in the present paper. The measured characteristic magnetic properties, which are the saturation magnetization, residual magnetization, coercive field and the field dependent permeability (AC-magnetization), are sensitive to fatigue and the corresponding material changes (martensitic transformation). In particular, the AC-magnetization was found to be very sensitive to small changes of the amount of strain induced martensite and therefore also to the degree of fatigue. Hence we conclude that applying magnetic minor loops are promising for the non-destructive evaluation of fatigue in austenitic stainless steel, even if a very small amount of strain induced martensite is formed

A Study on the Development of Nonglass Solar Vacuum Tube Collector

International Nuclear Information System (INIS)

Oh, Seung Jin

2008-02-01

Nature has been providing us energy from the beginning of the world. However human has hardly used it wisely. Solar energy is a kind of renewable energy from the nature. This study has been carried out to study the use of solar energy as it is harnessed in the form of thermal energy. Solar energy is one of the most promising energy resources such as hydrogen, biomass, wind and geothermal energy, because it is clean and inexhaustible. Space heating in buildings can be provided from solar energy by systems that are similar in many respects to water heater systems. By tapping into solar energy, we can not only solve the problem of energy shortage, but also can protect the environment and benefit the human beings. There are currently two types of evacuated tube; a single glass tube and a double glass tube. The former consists of a single glass tube which contains a flat or curved aluminium plate attached to a copper heat pipe or water flow pipe. The latter consists of rows of parallel transparent glass tubes, each of which contains an absorber tube. Evacuated tube collectors introduced above, however, pose some problems as they break rather easily under mechanical stresses. This paper introduces some preliminary results in design and fabrication of a non-glass solar vacuum tube collector in which the thermosyphon(heat pipe)made of copper is used as a heat transfer device. A series of tests have been performed to assess the ability of a non-glass solar vacuum tube collector. The series of experiments are as follows: 1)Vacuum level inside a vacuum tube. 2)Effects of the air remaining inside a vacuum tube on the temperature on the absorber plate. 3)Comparison of a non-glass vacuum solar collector with a single glass evacuated tube(SEIDO 5). Different vacuum levels inside non-glass vacuum tubes were applied to check any leakage or unexpected physical or chemical developments with time. The vacuum level changed from 10 -2 torr to 5torr in 5 days due to air infiltration from

Coiled Tube Gas Heaters For Nuclear Gas-Brayton Power Conversion

Energy Technology Data Exchange (ETDEWEB)

Peterson, Per F.

2018-03-31

This project developed an alternative design for heat exchangers for application to heating supercritical carbon dioxide (S-CO₂) or air for power conversion. We have identified an annular coiled tube bundle configuration–where hot sodium enters tubes from multiple vertical inlet manifold pipes, flows in a spiral pattern radially inward and downward, and then exits into an equal number of vertical outlet manifold pipes–as a potentially attractive option. The S-CO₂ gas or air flows radially outward through the tube bundle. Coiled tube gas heaters (CTGHs) are expected to have excellent thermal shock, long-term thermal creep, in-service inspection, and reparability characteristics, compared to alternative options. CTGHs have significant commonality with modern nuclear steam generators. Extensive experience exists with the design, manufacture, operation, in-service inspection and maintenance of nuclear steam generators. The U.S. Nuclear Regulatory Commission also has extensive experience with regulatory guidance documented in NUREG 0800. CTGHs leverage this experience and manufacturing capability. The most important difference between steam generators and gas-Brayton cycles such as the S-CO₂ cycle is that the heat exchangers must operate with counter flow with high effectiveness to minimize the pinch-point temperature difference between the hot liquid coolant and the heated gas. S-CO₂-cycle gas heaters also operate at sufficiently elevated temperatures that time dependent creep is important and allowable stresses are relatively low. Designing heat exchangers to operate in this regime requires configurations that minimize stresses and stress concentrations. The cylindrical tubes and cylindrical manifold pipes used in CTGHs are particularly effective geometries. The first major goal of this research project was to develop and experimentally validate a detailed, 3-D multi-phase (gas-solid-liquid) heat transport model for

Behavior of Corrosion of a Heat Pipe Cooling Device in a Computer

Directory of Open Access Journals (Sweden)

S. Rittidech

2017-12-01

Full Text Available The aim of this study was to perform life testing and to determine the effect of working time on the corrosion of a heat pipe used for cooling in a computer. The heat pipe was made from a copper tube. The heat pipe consists of evaporator and condenser section. It had a specification similar with the use in ordinary computers, the working fluid being distilled water. When the computer starts, the concentration of the copper solution slightly increases. The greater copper concentration was 0.00062 ppm upon 3000-5000 hours of testing. The surface traces of corrosion rises due to the oxidation of the porous material within the working fluid. The test found that oxygen (O and carbon (C are component contents.

Development and Manufacture of Cost-Effective Composite Drill Pipe

Energy Technology Data Exchange (ETDEWEB)

James C. Leslie

2008-12-31

Advanced Composite Products and Technology, Inc. (ACPT) has developed composite drill pipe (CDP) that matches the structural and strength properties of steel drill pipe, but weighs less than 50 percent of its steel counterpart. Funding for the multiyear research and development of CDP was provided by the U.S. Department of Energy Office of Fossil Energy through the Natural Gas and Oil Projects Management Division at the National Energy Technology Laboratory (NETL). Composite materials made of carbon fibers and epoxy resin offer mechanical properties comparable to steel at less than half the weight. Composite drill pipe consists of a composite material tube with standard drill pipe steel box and pin connections. Unlike metal drill pipe, composite drill pipe can be easily designed, ordered, and produced to meet specific requirements for specific applications. Because it uses standard joint connectors, CDP can be used in lieu of any part of or for the entire steel drill pipe section. For low curvature extended reach, deep directional drilling, or ultra deep onshore or offshore drilling, the increased strength to weight ratio of CDP will increase the limits in all three drilling applications. Deceased weight will reduce hauling costs and increase the amount of drill pipe allowed on offshore platforms. In extreme extended reach areas and high-angle directional drilling, drilling limits are associated with both high angle (fatigue) and frictional effects resulting from the combination of high angle curvature and/or total weight. The radius of curvature for a hole as small as 40 feet (12.2 meters) or a build rate of 140 degrees per 100 feet is within the fatigue limits of specially designed CDP. Other properties that can be incorporated into the design and manufacture of composite drill pipe and make it attractive for specific applications are corrosion resistance, non-magnetic intervals, and abrasion resistance coatings. Since CDP has little or no electromagnetic force

Stress analysis of HTR-10 steam generator heat exchanging tubes

International Nuclear Information System (INIS)

Dong Jianling; Zhang Xiaohang; Yin Dejian; Fu Jiyang

2001-01-01

Steam Generator (SG) heat exchanging tubes of 10 MW High Temperature Gas Cooled Reactor (HTR-10) are protective screens between the primary loop of helium with radioactivity and the secondary loop of feeding water and steam without radioactivity. Water and steam will enter into the primary loop when rupture of the heat exchanging tubes occurs, which lead to increase of the primary loop pressure and discharge of radioactive materials. Therefore it is important to guarantee the integrity of the tubes. The tube structure is spiral tube with small bending radius, which make it impossible to test with volumetric in-service detection. For such kind of spiral tube, using LBB concept to guarantee the integrity of the tubes is an important option. The author conducts stress analysis and calculation of HTR-10 SG heat exchanging tubes using the FEM code of piping stress analysis, PIPESTRESS. The maximum stress and the dangerous positions are obtained

Comparative study of linear and nonlinear ultrasonic techniques for evaluation thermal damage of tube like structures

International Nuclear Information System (INIS)

Li, Weibin; Cho, Younho; Li, Xianqiang

2013-01-01

Ultrasonic guided wave techniques have been widely used for long range nondestructive detection in tube like structures. The present paper investigates the ultrasonic linear and nonlinear parameters for evaluating the thermal damage in aluminum pipe. Specimens were subjected to thermal loading. Flexible polyvinylidene fluoride (PVDF) comb transducers were used to generate and receive the ultrasonic waves. The second harmonic wave generation technique was used to check the material nonlinearity change after different heat loadings. The conventional linear ultrasonic approach based on attenuation was also used to evaluate the thermal damages in specimens. The results show that the proposed experimental setup is viable to assess the thermal damage in an aluminum pipe. The ultrasonic nonlinear parameter is a promising candidate for the prediction of micro damages in a tube like structure

PIV Measurement of Pulsatile Flows in 3D Curved Tubes Using Refractive Index Matching Method

Energy Technology Data Exchange (ETDEWEB)

Hong, Hyeon Ji; Ji, Ho Seong; Kim, Kyung Chun [Pusan Nat’l Univ., Busan (Korea, Republic of)

2016-08-15

Three-dimensional models of stenosis blood vessels were prepared using a 3D printer. The models included a straight pipe with axisymmetric stenosis and a pipe that was bent 10° from the center of stenosis. A refractive index matching method was utilized to measure accurate velocity fields inside the 3D tubes. Three different pulsatile flows were generated and controlled by changing the rotational speed frequency of the peristaltic pump. Unsteady velocity fields were measured by a time-resolved particle image velocimetry method. Periodic shedding of vortices occurred and moves depended on the maximum velocity region. The sizes and the positions of the vortices and symmetry are influenced by mean Reynolds number and tube geometry. In the case of the bent pipe, a recirculation zone observed at the post-stenosis could explain the possibility of blood clot formation and blood clot adhesion in view of hemodynamics.

PIV Measurement of Pulsatile Flows in 3D Curved Tubes Using Refractive Index Matching Method

International Nuclear Information System (INIS)

Hong, Hyeon Ji; Ji, Ho Seong; Kim, Kyung Chun

2016-01-01

Three-dimensional models of stenosis blood vessels were prepared using a 3D printer. The models included a straight pipe with axisymmetric stenosis and a pipe that was bent 10° from the center of stenosis. A refractive index matching method was utilized to measure accurate velocity fields inside the 3D tubes. Three different pulsatile flows were generated and controlled by changing the rotational speed frequency of the peristaltic pump. Unsteady velocity fields were measured by a time-resolved particle image velocimetry method. Periodic shedding of vortices occurred and moves depended on the maximum velocity region. The sizes and the positions of the vortices and symmetry are influenced by mean Reynolds number and tube geometry. In the case of the bent pipe, a recirculation zone observed at the post-stenosis could explain the possibility of blood clot formation and blood clot adhesion in view of hemodynamics.

Open Loop Heat Pipe Radiator Having a Free-Piston for Wiping Condensed Working Fluid

Science.gov (United States)

Weinstein, Leonard M. (Inventor)

2015-01-01

An open loop heat pipe radiator comprises a radiator tube and a free-piston. The radiator tube has a first end, a second end, and a tube wall, and the tube wall has an inner surface and an outer surface. The free-piston is enclosed within the radiator tube and is capable of movement within the radiator tube between the first and second ends. The free-piston defines a first space between the free-piston, the first end, and the tube wall, and further defines a second space between the free-piston, the second end, and the tube wall. A gaseous-state working fluid, which was evaporated to remove waste heat, alternately enters the first and second spaces, and the free-piston wipes condensed working fluid from the inner surface of the tube wall as the free-piston alternately moves between the first and second ends. The condensed working fluid is then pumped back to the heat source.

High performance passive solar heating system with heat pipe energy transfer and latent heat storage

NARCIS (Netherlands)

Dijk, van H.A.L.; Galen, van E; Hensen, J.L.M.; Wit, de M.H.

1983-01-01

Preliminar results are reported from a current project on the development of a high performance passive solar heating system. Two special components are introduced: a. A heat pipe as a thermal diode tube for the efficient transfer of collected solar heat from the absorber plate to behind an

Thermomechanical CSM analysis of a superheater tube in transient state

Science.gov (United States)

Taler, Dawid; Madejski, Paweł

2011-12-01

The paper presents a thermomechanical computational solid mechanics analysis (CSM) of a pipe "double omega", used in the steam superheaters in circulating fluidized bed (CFB) boilers. The complex cross-section shape of the "double omega" tubes requires more precise analysis in order to prevent from failure as a result of the excessive temperature and thermal stresses. The results have been obtained using the finite volume method for transient state of superheater. The calculation was carried out for the section of pipe made of low-alloy steel.

Simulation and Experimental Determination of Technological Liquid Molding Parameters of Tubing Basalt Insulation

Directory of Open Access Journals (Sweden)

Yu. V. Badanina

2015-01-01

Full Text Available The article is dedicated to one of the most important and urgent tasks in mechanical engineering development - the creation of low-density and environmentally-friendly thermoinsulation from available cheap basalt fibers for products to operate at temperatures up to 700°C.One of the most effective applications of such thermo-insulation is to develop and provide highly porous coatings from short basalt fibers by liquid filtration for tubing (T to supply superheated up to 420° C steam under pressure of 35 MPa in the deep layers with severe highviscosity oil. Tubing with the short low-density basalt insulation can be used for a greater depth than the vacuum-insulated tubing, which are also called "thermo-cases", and do not fully meet business needs for long-term reliability of oil vacuum tubes, too large mass per unit length of their design and, as a consequence, the impossibility to use such pipes for deep wells.The aim of the work is to simulate a liquid filtration process of short fibers and determine technological parameters of producing thermal insulation coatings of tubing pipes from basalt fibers and mineral binder shaped as cylinders and cylindrical shells. The paper proposes a mathematical model of free filtration deposition of short fibers from liquid slurry, which describes dynamics of creating thermal insulation products and allows us to determine the rational parameters of their manufacturing process. It shows methods to improve the products quality while forming the thermal insulation by filtration through additional vacuum deposition of a filtrate chamber and the final prepressing of sediment layer, giving dimensions and shape to the final product.The paper defines a prescription hydro mass composition. It shows that to increase the compressive strength of highly fibrous rings and cylindrical shells it is necessary to use based on oxide А12O3 5-7% by weight mineral binder, which fixes basalt fibers in places of their contacts. It

Pipe drafting and design

CERN Document Server

Parisher, Roy A; Parisher

2000-01-01

Pipe designers and drafters provide thousands of piping drawings used in the layout of industrial and other facilities. The layouts must comply with safety codes, government standards, client specifications, budget, and start-up date. Pipe Drafting and Design, Second Edition provides step-by-step instructions to walk pipe designers and drafters and students in Engineering Design Graphics and Engineering Technology through the creation of piping arrangement and isometric drawings using symbols for fittings, flanges, valves, and mechanical equipment. The book is appropriate primarily for pipe

Performance analysis of a heat pipe solar collector having different pitch distance

Energy Technology Data Exchange (ETDEWEB)

Sivaraman, B.; Mohan, N.K. [Annamalai Univ., Tamil Nadu (India). Dept. of Mechanical Engineering

2006-07-01

Heat pipe solar collectors are more efficient than conventional solar collectors. This paper provided details of experimental analyses conducted to examine the effect of pitch distance on the heat pipe's performance. Two solar collectors with pitch distances of 7.5 cm and 8.5 cm were used in the study. Copper tubing was used as the container material, and methanol was selected as a working fluid for the experiments, which were conducted during the summer at a collector tilt angle of 11 degrees. Experiments were conducted and the impacts of various parameters were measured. Solar intensity was measured using a pyranometer. Water exit and inlet temperatures were measured using mercury thermometers. Results showed that the heat pipe performed optimally when the pitch distance was 0.085 m. 8 refs., 1 tab., 9 figs.

A high performance cocurrent-flow heat pipe for heat recovery applications

Science.gov (United States)

Saaski, E. W.; Hartl, J. C.

1980-01-01

By the introduction of a plate-and-tube separator assembly into a heat pipe vapor core, it has been demonstrated that axial transport capacity in reflux mode can be improved by up to a factor of 10. This improvement is largely the result of eliminating the countercurrent shear that commonly limits reflux heat pipe axial capacity. With benzene, axial heat fluxes up to 1800 W/sq cm were obtained in the temperature range 40 to 80 C, while heat flux densities up to 3000 W/sq cm were obtained with R-11 over the temperature range 40 to 80 C. These very high axial capacities compare favorably with liquid metal limits; the sonic limit for liquid sodium, for example, is 3000 W/sq cm at 657 C. Computational models developed for these cocurrent flow heat pipes agreed with experimental data within + or - 25%.

Control rod guide tube cleaning device

International Nuclear Information System (INIS)

Tsuji, Tadashi; Shiota, Yoshiaki.

1990-01-01

Since there was no exclusive device for cleaning control rods, no effective cleaning could not be conducted and there was a possibility that obstacles may not be recovered. Then, there are disposed a first pump for supplying pressurized water, a spray nozzle for forming a swirling flow in a control rod guide tube, a second pump for pressurizing water introduced by a sucking pipeline and a collecting device for recovering obstacles intruding to water from the second pump. The pressurized water supplied from the first pump is introduced to a head passing through a blowing pipe and jetted from the spray nozzle to the control rod guide tube. In this case, a swirling stream occurs and obstacles in the control guide tube are mixed into water. The water containing the obstacles passes from the sucking port through a pipeline, introduced to the second pump and recovered to the collecting device. Since there is no water staying portion upon cleaning operation, the obstacles accumulating over the entire region of the bottom of the guide tube can be recovered reliably and efficiently. (N.H.)

Film Thickness Estimation for the Oil Applied to the Inner Surface of Slim Tubes

Directory of Open Access Journals (Sweden)

Jozef Svetlík

2017-09-01

Full Text Available The article deals with the approximation of the results of experimental measurement of coating of the inner surface of slim pipes with special oil, using a dispersion oil fraction. The reason for such treatment of the inner surface of the tubes is the anti-corrosion protection or various other requirements. The oil manufacturer prescribes the minimum required layer to guarantee the anti-corrosion protection parameters. Therefore, it is advisable to know the most exact coating parameters for different pipe diameters. The measured results give us an assumption of how much oil is sufficient to coat the inside of a pipe. The main idea lies in the correct estimation of coefficients in the three-parameter exponential dependence. For the initial estimates, Nelder–Mead’s minimization method was used. The condition for meeting the lower estimate of the minimum thickness of the oil layer was determined. Following graphic processing of minimization of individual pipe diameters, in some cases, the coefficients were adjusted manually. The result is that the oil thickness depends on the distance of the investigated point from the beginning of the tube, or on the point of entry of the dispersion oil fraction.

Study on drop pressure and flow distribution of double-tube heat exchanger

International Nuclear Information System (INIS)

Liu Junqiang; Chen Minghui; Hu Yumin; Li Rizhu; Kong Dechun; Zhang Weijie

2007-01-01

The parallel connection channel pressure drop characters of the double-tube bundle heat exchange were experimentally investigated in this paper in order to find out how the flow of the heat exchanger is distributed and then to optimize the structure of heat exchanger according to the flow distribution. A double-tube bundle heat exchanger was built according to the similarity criteria. The experiment system was also built to test the optimization of the heat exchanger. The experiment results reveal that the calculating model is reliable and decreasing pipe space to optimize the heat exchanger is reasonable. (authors)

Origami tubes with reconfigurable polygonal cross-sections.

Science.gov (United States)

Filipov, E T; Paulino, G H; Tachi, T

2016-01-01

Thin sheets can be assembled into origami tubes to create a variety of deployable, reconfigurable and mechanistically unique three-dimensional structures. We introduce and explore origami tubes with polygonal, translational symmetric cross-sections that can reconfigure into numerous geometries. The tubular structures satisfy the mathematical definitions for flat and rigid foldability, meaning that they can fully unfold from a flattened state with deformations occurring only at the fold lines. The tubes do not need to be straight and can be constructed to follow a non-linear curved line when deployed. The cross-section and kinematics of the tubular structures can be reprogrammed by changing the direction of folding at some folds. We discuss the variety of tubular structures that can be conceived and we show limitations that govern the geometric design. We quantify the global stiffness of the origami tubes through eigenvalue and structural analyses and highlight the mechanical characteristics of these systems. The two-scale nature of this work indicates that, from a local viewpoint, the cross-sections of the polygonal tubes are reconfigurable while, from a global viewpoint, deployable tubes of desired shapes are achieved. This class of tubes has potential applications ranging from pipes and micro-robotics to deployable architecture in buildings.

Origami tubes with reconfigurable polygonal cross-sections

Science.gov (United States)

Filipov, E. T.; Paulino, G. H.; Tachi, T.

2016-01-01

Thin sheets can be assembled into origami tubes to create a variety of deployable, reconfigurable and mechanistically unique three-dimensional structures. We introduce and explore origami tubes with polygonal, translational symmetric cross-sections that can reconfigure into numerous geometries. The tubular structures satisfy the mathematical definitions for flat and rigid foldability, meaning that they can fully unfold from a flattened state with deformations occurring only at the fold lines. The tubes do not need to be straight and can be constructed to follow a non-linear curved line when deployed. The cross-section and kinematics of the tubular structures can be reprogrammed by changing the direction of folding at some folds. We discuss the variety of tubular structures that can be conceived and we show limitations that govern the geometric design. We quantify the global stiffness of the origami tubes through eigenvalue and structural analyses and highlight the mechanical characteristics of these systems. The two-scale nature of this work indicates that, from a local viewpoint, the cross-sections of the polygonal tubes are reconfigurable while, from a global viewpoint, deployable tubes of desired shapes are achieved. This class of tubes has potential applications ranging from pipes and micro-robotics to deployable architecture in buildings. PMID:26997894

Tube sheet design for PFBR steam generator

International Nuclear Information System (INIS)

Chellapandi, P.; Chetal, S.C.; Bhoje, S.B.

1991-01-01

Top and bottom tube sheets of PFBR Steam Generators have been analysed with 3D and axisymmetric models using CASTEM Programs. Analysis indicates that the effects of piping reactions at the inlet/outlet nozzles on the primary stresses in the tube sheets are negligible and the asymmetricity of the deformation pattern introduced in the tube sheet by the presence of inlet/outlet and manhole nozzles is insignificant. The minimum tube sheet thicknesses for evaporator and reheater are 135 mm and 75 mm respectively. Further analysis has indicated the minimum fillet radius at the junction of tube sheet and dished end should be 20 mm. Simplified methodology has been developed to arrive at the number of thermal baffles required to protect the tube sheet against fatigue damage due to thermal transient. This method has been applied to PFBR steam generators to determine the required number of thermal baffles. For protecting the bottom tube sheet of evaporator against the thermal shock due to feed water and secondary pump trip, one thermal shield is found to be sufficient. Further analysis is required to decide upon the actual number to take care of the severe thermal transient, following the event of sudden dumping of water/steam, immediately after the sodium-water reaction. (author)

Convective heat transfer in foams under laminar flow in pipes and tube bundles.

Science.gov (United States)

Attia, Joseph A; McKinley, Ian M; Moreno-Magana, David; Pilon, Laurent

2012-12-01

The present study reports experimental data and scaling analysis for forced convection of foams and microfoams in laminar flow in circular and rectangular tubes as well as in tube bundles. Foams and microfoams are pseudoplastic (shear thinning) two-phase fluids consisting of tightly packed bubbles with diameters ranging from tens of microns to a few millimeters. They have found applications in separation processes, soil remediation, oil recovery, water treatment, food processes, as well as in fire fighting and in heat exchangers. First, aqueous solutions of surfactant Tween 20 with different concentrations were used to generate microfoams with various porosity, bubble size distribution, and rheological behavior. These different microfoams were flowed in uniformly heated circular tubes of different diameter instrumented with thermocouples. A wide range of heat fluxes and flow rates were explored. Experimental data were compared with analytical and semi-empirical expressions derived and validated for single-phase power-law fluids. These correlations were extended to two-phase foams by defining the Reynolds number based on the effective viscosity and density of microfoams. However, the local Nusselt and Prandtl numbers were defined based on the specific heat and thermal conductivity of water. Indeed, the heated wall was continuously in contact with a film of water controlling convective heat transfer to the microfoams. Overall, good agreement between experimental results and model predictions was obtained for all experimental conditions considered. Finally, the same approach was shown to be also valid for experimental data reported in the literature for laminar forced convection of microfoams in rectangular minichannels and of macrofoams across aligned and staggered tube bundles with constant wall heat flux.

Controlled Thermal-Mechanical Processing of Tubes and Pipes for Enhanced Manufacturing and Performance

Energy Technology Data Exchange (ETDEWEB)

Kolarik, Robert V.

2005-11-11

The Alloy Steel Business of The Timken Company won an award for the controlled thermo-mechanical processing (CTMP) project and assembled a strong international public/private partnership to execute the project. The premise of the CTMP work was to combine Timken's product understanding with its process expertise and knowledge of metallurgical and deformation fundamentals developed during the project to build a predictive process design capability. The CTMP effort succeeded in delivering a pc-based capability in the tube optimization model, with a virtual pilot plant (VPP) feature to represent the desired tube making process to predict the resultant microstructure tailored for the desired application. Additional tasks included a system for direct, online measurement of grain size and demonstration of application of CTMP via robotically enhanced manufacturing.

Pipe-to-pipe impact program

International Nuclear Information System (INIS)

Alzheimer, J.M.; Bampton, M.C.C.; Friley, J.R.; Simonen, F.A.

1984-06-01

This report documents the tests and analyses performed as part of the Pipe-to-Pipe Impact (PTPI) Program at the Pacific Northwest Laboratory. This work was performed to assist the NRC in making licensing decisions regarding pipe-to-pipe impact events following postulated breaks in high energy fluid system piping. The report scope encompasses work conducted from the program's start through the completion of the initial hot oil tests. The test equipment, procedures, and results are described, as are analytic studies of failure potential and data correlation. Because the PTPI Program is only partially completed, the total significance of the current test results cannot yet be accurately assessed. Therefore, although trends in the data are discussed, final conclusions and recommendations will be possible only after the completion of the program, which is scheduled to end in FY 1984

Failure Analysis of Cracked FS-85 Tubing and ASTAR-811C End Caps

International Nuclear Information System (INIS)

ME Petrichek

2006-01-01

Failure analyses were performed on cracked FS-85 tubing and ASTAR-811C and caps which had been fabricated as components of biaxial creep specimens meant to support materials testing for the NR Space program. During the failure analyses of cracked FS-85 tubing, it was determined that the failure potentially could be due to two effects: possible copper contamination from the EDM (electro-discharge machined) recast layer and/or an insufficient solution anneal. to prevent similar failures in the future, a more formal analysis should be done after each processing step to ensure the quality of the material before further processing. During machining of the ASTAR-811FC rod to form end caps for biaxial creep specimens, linear defects were observed along the center portion of the end caps. These defects were only found in material that was processed from the top portion of the ingot. The linear defects were attributed to a probable residual ingot pipe that was not removed from the ingot. During the subsequent processing of the ingot to rod, the processing temperatures were not high enough to allow self healing of the ingot's residual pipe defect. To prevent this from occurring in the future, it is necessary to ensure that complete removal of the as-melted ingot pipe is verified by suitable non-destructive evaluation (NDE)

Investigation of straitified and countercurrent flows in horizontal piping during a loss-of-coolant accident

International Nuclear Information System (INIS)

Bourteele, J.P.

1980-06-01

The ECTHOR program consists in a loop having as objective to study the flow regimes in horizontal pipings (stratification, countercurrent flows) in conditions representative of small break transients within commercial PWR. The ECTHOR tests are in process. Experimental results are already available and are presented in this paper: scaling problem, U tube experiments, hot leg experiments, high pressure tests

Externally mounted radioactivity detector for MWD employing radial inline scintillator and photomultiplier tube

International Nuclear Information System (INIS)

Meisner, J.E.; Mumby, E.S.; Groeschel, V.E.

1991-01-01

Improved radioactivity well logging may be achieved by mounting a scintillator and photomultiplier tube in a single case interfacing with a hole extending through a drill collar at the lower end of a drill string so that measurements can be made while drilling. Radioactive sources (when required for well logging) are mounted in cavities which open to the exterior of the drill collar. Light from the scintillator is coupled directly to the aligned photomultiplier tube both of which are mounted in a case extending radially within the drill collar and sealingly engaging an electronics housing within the drill collar and the drill collar wall surrounding the hole. The scintillator is of greater diameter than the photomultiplier tube. A frustoconical light pipe connects the scintillator and the photomultiplier tube, channeling scintillation in the crystal to the photomultiplier to provide an amplified detection capability over that for a scintillator having the same diameter as the photomultiplier tube. (author)

Selenide isotope generator for the Galileo Mission: copper/water axially-grooved heat pipe topical report

International Nuclear Information System (INIS)

Strazza, N.P.

1979-01-01

This report presents a summary of the major accomplishments for the development, fabrication, and testing of axially-grooved copper/water heat pipes for Selenide Isotopic Generator (SIG) applications. The early development consisted of chemical, physical, and analytical studies to define an axially-grooved tube geometry that could be successfully fabricated and provide the desired long term (up to seven years) performance is presented. Heat pipe fabrication procedures, measured performance and accelerated life testing of heat pipes S/Ns AL-5 and LT-57 conducted at B and K Engineering are discussed. S/N AL-5 was the first axially-grooved copper/water heat pipe that was fabricated with the new internal coating process for cupric oxide (CuO) and the cleaning and water preparation methods developed by Battelle Columbus Laboratories. Heat pipe S/N LT-57 was fabricated along with sixty other axially-grooved heat pipes allocated for life testing at Teledyne Energy Systems. As of June 25, 1979, heat pipes S/Ns AL-5 and LT-57 have been accelerated life tested for 13,310 and 6,292 respectively, at a nominal operating temperature of 225 0 C without any signs of thermal performance degradation

A study on the impulse wave discharged from the exit of a right-angle pipe bend

International Nuclear Information System (INIS)

Lee, D. H.; Hur, S. C.; Kweon, Y. H.; Kim, H. D.

2001-01-01

The current study addresses experimental and computational work of impulse wave discharged from the exit of two kinds of right-angle pipe bends, which are attached to the open end of a simple shock tube. The weak normal shock wave with its magnitude of Mach number from 1.02 to 1.20 is employed to obtain the impulse wave propagating outside the exit of the pipe bends. A Schlieren optical system visualizes the impulse wave discharged from the exit of the pipe bends at an instant. The experimental data of the magnitude of the impulse wave and its propagating directivity are analyzed to characterize the impulse waves discharged from the exit of the pipe bends and compared with those discharged from a straight pipe. Computational results well predict the experimented dynamic behaviors of the impulse wave. The results obtained show that a right-angle miter bend considerably reduces the magnitude of the impulse wave and its directivity toward to the pipe axis, compared with the straight pipe and right-angle smooth bend. It is believed that the right-angle miter bend pipe can play a role of a passive control against the impulse wave

Experimental study of Large-scale cryogenic Pulsating Heat Pipe

Science.gov (United States)

Barba, Maria; Bruce, Romain; Bonelli, Antoine; Baudouy, Bertrand

2017-12-01

Pulsating Heat Pipes (PHP) are passive two-phase heat transfer devices consisting of a long capillary tube bent into many U-turns connecting the condenser part to the evaporator part. They are thermally driven by an oscillatory flow of liquid slugs and vapor plugs coming from phase changes and pressure differences along the tube. The coupling of hydrodynamic and thermodynamic effects allows high heat transfer performances. Three closed-loop pulsating heat pipes have been developed by the DACM (Department of Accelerators, Cryogenics and Magnetism) of CEA Paris-Saclay, France. Each PHP measures 3.7 meters long (0.35 m for the condenser and the evaporator and 3 m for the adiabatic part), being almost 20 times longer than the longest cryogenic PHP tested. These PHPs have 36, 22 and 12 parallel channels. Numerous tests have been performed in horizontal position (the closest configuration to non-gravity) using nitrogen as working fluid, operating between 75 and 90 K. The inner and outer diameters of the stainless steel capillary tubes are 1.5 and 2 mm respectively. The PHPs were operated at different filling ratios (20 to 90 %), heat input powers (3 to 20 W) and evaporator and condenser temperatures (75 to 90 K). As a result, the PHP with 36 parallel channels achieves a certain level of stability during more than thirty minutes with an effective thermal conductivity up to 200 kW/m.K at 10 W heat load and during forty minutes with an effective thermal conductivity close to 300 kW/m.K at 5 W heat load.

Design and technology parameters influence on durability for heat exchangers tube to tubesheet joints

Science.gov (United States)

Ripeanu, R. G.

2017-02-01

The main failures of heat exchangers are: corrosion of tubes and jacket, tubes blockage and failures of tube to tubesheet joints also by corrosion. The most critical zone is tube to tubesheet joints. Depending on types of tube to tubesheet joints, in order to better respect conditions of tension and compression, this paper analyses the tubesheet holes shapes, smooth and with a grove, on corrosion behavior. In the case of welding tubes with tubesheet, welding parameters modify corrosion behavior. Were realized welded joints by three welding regimes and tested at corrosion in two media, tap water and industrial water. Were tested also samples made of smooth tubes, finned tubes and tubes coated with a passive product as applied by a heat exchanger manufacturer. For all samples, the roughness parameters were measured, before and after the corrosion tests. The obtained corrosion rates show that stress values and their distribution along the joint modify the corrosion behavior. The optimum welding parameters were established in order to increase the joint durability. The paper has shown that passive product used is not proper chosen and the technology of obtaining rolled thread pipes diminishes tubes’ durability by increasing the corrosion rate.

The installation welding of pressure water reactor coolant piping

International Nuclear Information System (INIS)

Deng Feng

2010-01-01

Large pressure water reactor nuclear power plants are constructing in our country. There are three symmetry standard loops in reactor coolant system. Each loop possesses a steam generator and a primary poop, in which one of the loops is equipped with a pressurizer. These components are connected with reactor pressure vessel by installation welding of the coolant piping. The integrity of reactor coolant pressure boundary is the second barrier to protect the radioactive substance from release to outside, so the safe operation of nuclear power plant is closely related to the quality of coolant piping installation welding. The heavy tube with super low carbon content austenitic stainless steel is selected for coolant piping. This kind of material has good welding behavior, but the poor thermal conductivity, the big liner expansion coefficient and the big welding deformation will cause bigger welding stress. To reduce the welding deformation, to control the dimension precision, to reduce the residual stress and to ensure the welding quality the installation sequence should be properly designed and the welding technology should be properly controlled. (authors)

Corrosion caused by elevator and spider marks on CRA pipe: Comparison of conventional inserts and a new gripping system

Energy Technology Data Exchange (ETDEWEB)

NONE

1997-05-01

Corrosion-resistant alloys (CRA) are used to reduce corrosion damage to casing and tubing strings and prolong the life span of the well pipe. An analysis of various corrosion mechanisms shows that surface integrity is an important factor in corrosion prevention. Surface damage caused by inappropriate handling or conventional slip markings contribute directly to the development and propagation of corrosion. A newly developed gripping system distributes the load equally onto a large number of small peaks, minimizing the indentation of each single peak. The new gripping system does not damage the surface integrity of the pipe, virtually eliminating the corrosion potential.

Film holder for radiographing tubing

International Nuclear Information System (INIS)

Davis, E.V.; Foster, B.E.

1976-01-01

A film cassette is described which may be easily placed about tubing or piping and readily held in place while radiographic inspection is performed. A pair of precurved light-impervious semi-rigid plastic sheets, hinged at one edge, enclose sheet film together with any metallic foils or screens. Other edges are made light-tight with removable caps, and the entire unit is held securely about the object to be radiographed with a releasable fastener such as a strip of Velcro

Film holder for radiographing tubing

Science.gov (United States)

Davis, Earl V.; Foster, Billy E.

1976-01-01

A film cassette is provided which may be easily placed about tubing or piping and readily held in place while radiographic inspection is performed. A pair of precurved light-impervious semi-rigid plastic sheets, hinged at one edge, enclose sheet film together with any metallic foils or screens. Other edges are made light-tight with removable caps, and the entire unit is held securely about the object to be radiographed with a releasable fastener such as a strip of Velcro.

Monitoring of Soft Deposition Layers in Liquid-Filled Tubes with Guided Acoustic Waves Excited by Clamp-on Transducers.

Science.gov (United States)

Tietze, Sabrina; Singer, Ferdinand; Lasota, Sandra; Ebert, Sandra; Landskron, Johannes; Schwuchow, Katrin; Drese, Klaus Stefan; Lindner, Gerhard

2018-02-09

The monitoring of liquid-filled tubes with respect to the formation of soft deposition layers such as biofilms on the inner walls calls for non-invasive and long-term stable sensors, which can be attached to existing pipe structures. For this task a method is developed, which uses an ultrasonic clamp-on device. This method is based on the impact of such deposition layers on the propagation of circumferential guided waves on the pipe wall. Such waves are partly converted into longitudinal compressional waves in the liquid, which are back-converted to guided waves in a circular cross section of the pipe. Validating this approach, laboratory experiments with gelatin deposition layers on steel tubes exhibited a distinguishable sensitivity of both wave branches with respect to the thickness of such layers. This allows the monitoring of the layer growth.

Experimental determination of the thickness of aluminum cascade pipes in the presence of UF{sub 6} gas during enrichment measurements

Energy Technology Data Exchange (ETDEWEB)

Lombardi, M.L., E-mail: lombardi@lanl.gov [Los Alamos National Laboratory, P.O. Box 1663, Los Alamos NM 87545 (United States); Favalli, A.; Goda, J.M.; Ianakiev, K.D.; MacArthur, D.W.; Moss, C.E. [Los Alamos National Laboratory, P.O. Box 1663, Los Alamos NM 87545 (United States)

2012-04-21

We present a method of determining the wall thickness of a pipe in a Gas Centrifuge Enrichment Plant (GCEP) when an empty pipe measurement is not feasible. Our method uses an X-ray tube for transmission measurements and a lanthanum bromide (LaBr{sub 3}) scintillation detector on the opposite side of the pipe. Two filters, molybdenum (K-edge 20.0 keV) and palladium (K-edge 24.35 keV) are used to transform the bremsstrahlung spectra produced by the X-ray tube into more useful, sharply peaked, spectra. The maximum energies of the peaks are determined by the K-edges of the filters. The attenuation properties of the uranium hexafluoride (UF{sub 6}) gas allow us to determine wall thickness by looking at the ratio of selected regions of interest (ROIs) of the Mo and Pd transmitted spectra. While the attenuation factor at these two transmission energies in the UF{sub 6} gas is nearly equal, attenuation in the aluminum pipe wall at these two energies differs by a factor of about 60. This difference allows measurement of attenuation in the pipe independent of attenuation in the UF{sub 6} gas. Feasibility studies were performed using analytical calculations, and filter thicknesses were optimized. In order to experimentally validate our attenuation measurement method, a UF{sub 6} source with variable enrichment and pipe thickness was built. We describe the experimental procedure used to verify our previous calculations and present recent results.

Influence of the receiver’s back surface radiative characteristics on the performance of a heat-pipe evacuated-tube solar collector

International Nuclear Information System (INIS)

Zheng, Hongfei; Xiong, Jianying; Su, Yuehong; Zhang, Haiyin

2014-01-01

Highlights: • A model for describing the heat transfer characteristics of the ETSC is derived. • A method by performing roughness treatment is proposed to change the emissivity. • Increasing the receiver’s back surface emissivity can greatly affect the heat loss. • Real weather test verifies the proposed method in controlling overheat phenomenon. - Abstract: The receiver’s back surface radiative characteristics of a heat-pipe evacuated-tube solar collector (ETSC) may have a significant influence on its performance. This influence is generally related to the back surface emissivity and temperature; however it has been not studied previously. This paper firstly presents a heat transfer model for the ETSC, which is then derived to characterize the relationship between the heat loss and the back surface emissivity of the ETSC. A steady state experiment has been also performed to measure the heat loss of ETSC with different back surface emissivity values. The experimental results indicate that the heat loss of the ETSC increases with the increase of the back surface emissivity, but the rate of increase differs for different operation temperatures. When the back surface emissivity increases from 0.03 to 0.12, the heat loss of ETSC only increases by 31% when the operation temperature is below 100 °C, but the heat loss will increase to 96% when the operation temperature is over 200 °C. This means that the change of back surface emissivity can significantly affect the performance of the ETSC at higher temperature but affect little at lower temperature. Based on this, a novel method by performing roughness treatment on the receiver’s back surface is proposed to solve the overheating problem of ETSC in summer. Two solar water heaters including 6 ETSCs with standard and roughness-treated tubes were tested under real weather condition. Experiment reveals that when the water temperature in tank is below 60 °C, the two solar water heaters own similar temperature

Study of thermal and hydraulic efficiency of supersonic tube of temperature stratification

Science.gov (United States)

Tsynaeva, Anna A.; Nikitin, Maxim N.; Tsynaeva, Ekaterina A.

2017-10-01

Efficiency of supersonic pipe for temperature stratification with finned subsonic surface of heat transfer is the major of this paper. Thermal and hydraulic analyses of this pipe were conducted to asses effects from installation of longitudinal rectangular and parabolic fins as well as studs of cylindrical, rectangular and parabolic profiles. The analysis was performed based on refined empirical equations of similarity, dedicated to heat transfer of high-speed gas flow with plain wall, and Kármán equation with Nikuradze constants. Results revealed cylindrical studs (with height-to-diameter ratio of 5:1) to be 1.5 times more efficient than rectangular fins of the same height. At the same time rectangular fins (with height-to-thickness ratio of 5:1) were tend to enhance heat transfer rate up to 2.67 times compared to bare walls from subsonic side of the pipe. Longitudinal parabolic fins have minuscule effect on combined efficiency of considered pipe since extra head losses void any gain of heat transfer. Obtained results provide perspective of increasing efficiency of supersonic tube for temperature stratification. This significantly broadens device applicability in thermostatting systems for equipment, cooling systems for energy converting machinery, turbine blades and aerotechnics.

Evaluation on the thermal-hydraulic behavior of condensation pool and piping system

Energy Technology Data Exchange (ETDEWEB)

Kwon, Soon Bum; Lee, B. E.; Baek, S. C.; Joo, S. Y.; Lee, D. E.; Woo, S. W. [Kyungpook National Univ., Daegu (Korea, Republic of)

2002-03-15

The In-containment Refueling Water Storage Tank (IRWST) has the function of heat sink, when steam is released from the pressurizer. The hydrodynamic behaviors occurring at the piping system and sparger are very complex because of the wide variety of operating conditions and the complex geometry. Hydrodynamic behavior when air is discharged through a sparger in a condensation pool is investigated using CFD techniques in the present study. The effect of pressure acting on the sparger header during both water and air discharge through the sparger is studied. In addition, pressure oscillation occurring in the IRWST during air discharge through the sparger is studied for a better understanding of mechanisms of air discharge md an advanced evaluation technology of reactor safety. Understanding of flow behaviors occurring m the various types of pipes when POSRV is opened are also very important because those are very complex and may damage the structures of reactor coolant system. The principle of shock tube has been applied to analyze flow behaviors occurring in the piping system and several important phenomena which can be used for the evaluation of nuclear reactor safety has been obtained.

Comparing studies for an optimization of steam-heated tube bundle heat exchangers

International Nuclear Information System (INIS)

Horn, M.

1975-01-01

The problems of designing an apparatus are to be shown by the example of the steam-heated tube bundle heat exchanger, and optimizations are to be carried through by relevant examples. From the results of the optimization, a set of apparatus types is to be derived where the dimensions of the shell and the heat pipes as well as the length of the tube bundle are to be determined by as few data as possible. (orig./TK) [de

Pipe whip: a summary of the damage observed in BNL pipe-on-pipe impact tests

International Nuclear Information System (INIS)

Baum, M.R.

1987-01-01

This paper describes examples of the damage resulting from the impact of a whipping pipe on a nearby pressurised pipe. The work is a by-product of a study of the motion of a whipping pipe. The tests were conducted with small-diameter pipes mounted in rigid supports and hence the results are not directly applicable to large-scale plant applications where flexible support mountings are employed. The results illustrate the influence of whipping pipe energy, impact position and support type on the damage sustained by the target pipe. (author)

Heat pipes and use of heat pipes in furnace exhaust

Science.gov (United States)

Polcyn, Adam D.

2010-12-28

An array of a plurality of heat pipe are mounted in spaced relationship to one another with the hot end of the heat pipes in a heated environment, e.g. the exhaust flue of a furnace, and the cold end outside the furnace. Heat conversion equipment is connected to the cold end of the heat pipes.

Flow induced vibration of secondary piping of LMFBR

International Nuclear Information System (INIS)

Gibert, R.J.; Axisa, F.

1977-01-01

This paper presents a method for evaluating the characteristics of vibrations caused by internal flow in three-dimensional piping systems conveying high density fluids. The excitation of the circuit is mainly caused by the flow singularities, and it is shown that the problem may be reduced to calculate the response of the circuit to an acoustical pressure discontinuity, localised at each flow singularity. The paper is divided into two main parts: First part is devoted to the theoretical formulation of the coupled acoustical-mechanical problem and to its numerical solution by the french computer code TEDEL. Second part describes an experimental test of the method. The tested piping system consists of a stainless steel tube circuit comprising four 909 bends, conveying water. Vibrations are excited by a half closed gate valve. Satisfactory results are obtained concerning both the frequencies of resonance of the circuit and the level of the vibrations observed

Numerical simulation of flow and melting characteristics of seawater-ice crystals two-phase flow in inlet straight pipe of shell and tube heat exchanger of polar ship

Science.gov (United States)

Xu, Li; Huang, Chang-Xu; Huang, Zhen-Fei; Sun, Qiang; Li, Jie

2018-05-01

The ice crystal particles are easy to enter into the seawater cooling system of polar ship together with seawater when it sails in the Arctic. They are easy to accumulate in the pipeline, causing serious blockage of the cooling pipe. In this study, the flow and melting characteristics of ice particles-seawater two-phase flow in inlet straight pipe of shell-and-tube heat exchanger were numerically simulated by using Eulerian-Eulerian two-fluid model coupled with the interphase heat and mass transfer model. The influences of inlet ice packing factor, ice crystal particle diameter, and inlet velocity on the distribution and melting characteristics of ice crystals were investigated. The degree of asymmetry of the distribution of ice crystals in the cross section decreases gradually when the IPF changes from 5 to 15%. The volume fractions of ice crystals near the top of the outlet cross section are 19.59, 19.51, and 22.24% respectively for ice packing factor of 5, 10 and 15%. When the particle diameter is 0.5 mm, the ice crystals are gradually stratified during the flow process. With particle diameters of 1.0 and 2.0 mm, the region with the highest volume fraction of ice crystals is a small circle and the contours in the cloud map are compact. The greater the inlet flow velocity, the less stratified the ice crystals and the more obvious the turbulence on the outlet cross section. The average volume fraction of ice crystals along the flow direction is firstly rapidly reduced and then stabilized after 300 mm.

Pipe support

International Nuclear Information System (INIS)

Pollono, L.P.

1979-01-01

A pipe support for high temperature, thin-walled piping runs such as those used in nuclear systems is described. A section of the pipe to be suppported is encircled by a tubular inner member comprised of two walls with an annular space therebetween. Compacted load-bearing thermal insulation is encapsulated within the annular space, and the inner member is clamped to the pipe by a constant clamping force split-ring clamp. The clamp may be connected to pipe hangers which provide desired support for the pipe

Pipe clamp effects on thin-walled pipe design

International Nuclear Information System (INIS)

Lindquist, M.R.

1980-01-01

Clamp induced stresses in FFTF piping are sufficiently large to require structural assessment. The basic principles and procedures used in analyzing FFTF piping at clamp support locations for compliance with ASME Code rules are given. Typical results from a three-dimensional shell finite element pipe model with clamp loads applied over the clamp/pipe contact area are shown. Analyses performed to categorize clamp induced piping loads as primary or secondary in nature are described. The ELCLAMP Computer Code, which performs analyses at clamp locations combining clamp induced stresses with stresses from overall piping system loads, is discussed. Grouping and enveloping methods to reduce the number of individual clamp locations requiring analysis are described

Safety catching device for pipe lines in missile shielding cylinders of nuclear power plants

International Nuclear Information System (INIS)

Hering, S.; Doll, B.

1975-01-01

The safety catching device for pipes in the missile shielding cylinders consists of a flexible steel cable surrounding the pipe in a distance in U-shape. The arrester cable - which works as a spring and is freely movable in all directions - is attached to the cylinder wall. For this, the ends of the cable are primarily fastened to anchor boxes which are then inserted in a stay tube with the same axis as the cable ends. The anchor boxes are fastened to the outer wall of the missile shielding cylinder by anchor bolts and holding plates. (DG/AK) [de

Analysis of autofrettaged metal tubes

International Nuclear Information System (INIS)

Malik, M. Afzaal; Khan, Muddasar; Rashid, Badar; Khushnood, Shahab

2007-01-01

Thick-walled cylinders are widely used as compressor cylinders, pump cylinders, high pressure tubing, process reactors and vessels, nuclear reactors, isostatic vessels and gun barrels. In practice, cylinders are generally subjected to sudden and frequently drastic pressure fluctuations, such as the pressure generated in a gun barrel upon the firing of the weapon, pressure reversals in pump cylinders or in process reactors employing high-pressure piping, necessitating enhanced strength of such cylinders. A process for enhancing the strength of thick-walled cylinders has been in service, and is referred to as 'autofrettage'. It extends the service life of the cylinder. The autofrettage is achieved by increasing elastic strength of a cylinder with various methods such as hydraulic pressurization, mechanical swaging, or by utilizing the pressure of a powder gas. This research work deals with the hydraulic and mechanical autofrettage of metal tubes with the objective to attain enhanced strength. Five metal tubes are taken randomly for analysis purpose. The experimental data for five metal tubes is obtained to analyze the behavior of different parameters used during, before, and after autofrettage process. For this research, two-stage autofrettage is taken into consideration. The modeling of the metal tube is carried out in WildFire-ProEngineering, and for analysis purpose, finite element software ANSYS7 and COSMOS are used. The graphical analysis of swage autofrettage is carried out using MATLAB7. The results are validated using available experimental and numerical data. (author)

Heat pipes and heat pipe exchangers for heat recovery systems

Energy Technology Data Exchange (ETDEWEB)

Vasiliev, L L; Grakovich, L P; Kiselev, V G; Kurustalev, D K; Matveev, Yu

1984-01-01

Heat pipes and heat pipe exchangers are of great importance in power engineering as a means of recovering waste heat of industrial enterprises, solar energy, geothermal waters and deep soil. Heat pipes are highly effective heat transfer units for transferring thermal energy over large distance (tens of meters) with low temperature drops. Their heat transfer characteristics and reliable working for more than 10-15 yr permit the design of new systems with higher heat engineering parameters.

Analytical studies of blowdown thrust force and dynamic response of pipe at pipe rupture accident

International Nuclear Information System (INIS)

Miyazaki, Noriyuki

1985-01-01

The motion of a pipe due to blowdown thrust when the pipe broke is called pipe whip. In LWR power plants, by installing restraints, the motion of a pipe when it broke is suppressed, so that the damage does not spread to neighboring equipment by pipe whip. When the pipe whip of a piping system in a LWR power plant is analyzed, blowdown thrust and the dynamic response of a pipe-restraint system are calculated with a computer. The blowdown thrust can be calculated by using such physical quantities as the pressure, flow velocity, density and so on in the system at the time of blowdown, obtained by the thermal-fluid analysis code at LOCA. The dynamic response of a piping-restraint system can be determined by the stress analysis code using finite element method taking the blowdown thrust as an external force acting on the piping. In this study, the validity of the analysis techniques was verified by comparing with the experimental results of the measurement of blowdown thrust and the pipe whip of a piping-restraint system, carried out in the Japan Atomic Energy Research Institute. Also the simplified analysis method to give the maximum strain on a pipe surface is presented. (Kako, I.)

Design Evaluation of a Piping System in the SELFA Sodium Test Facility

Energy Technology Data Exchange (ETDEWEB)

Son, Seok-Kwon; Jo, Young-Chul; Lee, Hyeong-Yeon; Jeong, Ji-Young [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

2015-10-15

In this study, design evaluations on the SELFA piping system has been conducted according to the ASME B31.1 and RCC-MRx RD-3600. The conservatism of the two codes was quantified based on the evaluation results. It was shown that B31.1 was more conservative for the sustained loads while less conservative for thermal expansion loads when compare with those of RD-3600. However, all the evaluation results according to the two codes were within the code allowables. There are two main piping systems in the SELFA test loop. In this study, the integrity of the SELFA piping system has been evaluated according to the two design-by-rule (DBR) codes of ASME B31.1 and RCC-MRx RD-3600. B31.1 is an industry design code for power piping while RD-3600 is a class 3 nuclear DBR code. The conservatism of the two codes was quantified based on the evaluation results as per the two DBR codes. The sodium test facility of the SELFA is under construction at KAERI for the investigation of thermo-hydraulic behavior of finned-tube sodium-to-air heat exchanger.

Piping reliability model development, validation and its applications to light water reactor piping

International Nuclear Information System (INIS)

Woo, H.H.

1983-01-01

A brief description is provided of a three-year effort undertaken by the Lawrence Livermore National Laboratory for the piping reliability project. The ultimate goal of this project is to provide guidance for nuclear piping design so that high-reliability piping systems can be built. Based on the results studied so far, it is concluded that the reliability approach can undoubtedly help in understanding not only how to assess and improve the safety of the piping systems but also how to design more reliable piping systems

Pipes of glassfiber reinforced plastics and prestressed concrete for hot-water transportation

International Nuclear Information System (INIS)

Schmeling, P.; Roseen, R.

1980-06-01

The report constitutes stage 2-3 of a project for the evaluation of pipes made from glass reinforced plastics and prestressed concrete. This stage was made possible through funds from the Swedish National Board for Energy Source Development and the participation of three industrial firms. Experimental pipes of large dimensions (O.D. 0.5 m) were tested at elevated temperatures and pressures. The glass reinforced plastic tubes showed in general an acceptable short term strength at 100-110 degree C. Further long term testing is needed in order to predict the life time; their manufacture requires a strictrly controlled process. The pipes made from prestressed concrete were tested at 95 and 110 degree C for more than a year with good results, and their resistence to thermal shocks was shown to be acceptable. Long term stress relaxation of the EPDM rubber for the joints was measured at 125 and 110 degree C. The best rubbers can be used for 3 years at 110 degree C and a compression of 35 percent, a longer life time is most probable but cannot be foreseen until results from continued testing have been collected. It was demonstrated that the relaxation rate is lowered in water with low oxygen contents. (author)

Perturbation treatment of the longitudinal coupling impedance of a toroidal beam tube

International Nuclear Information System (INIS)

Hahn, H.; Tepikian, S.

1991-01-01

A simple analytical expression for the longitudinal coupling impedance of a toroidal beam tube below the resonance region has been derived by expanding the electromagnetic fields of the toroidal beam tube in a power series in curvature and substituting directly into Maxwell's equations. The resulting expression consists of the impedance of the straight beam pipe plus a correction terms due to the curvature. It has been verified that this result gives excellent agreement to the exact solution below the first resonance. 5 refs., 2 figs., 3 tabs

Piping engineering and operation

International Nuclear Information System (INIS)

1993-01-01

The conference 'Piping Engineering and Operation' was organized by the Institution of Mechanical Engineers in November/December 1993 to follow on from similar successful events of 1985 and 1989, which were attended by representatives from all sectors of the piping industry. Development of engineering and operation of piping systems in all aspects, including non-metallic materials, are highlighted. The range of issues covered represents a balance between current practices and implementation of future international standards. Twenty papers are printed. Two, which are concerned with pressurized pipes or steam lines in the nuclear industry, are indexed separately. (Author)

Tube Expansion Under Various Down-Hole End Conditions

Directory of Open Access Journals (Sweden)

FJ Sanchez

2013-06-01

Full Text Available Fossil hydrocarbons are indispensables commodities that motorize the global economy, and oil and gas are two of those conventional fuels that have been extracted and processed for over a century. During last decade, operators face challenges discovering and developing reservoirs commonly found up to several kilometers underground, for which advanced technologies are developed through different research programs. In order to optimize the current processes to drill and construct oil/gas wells, a large number of mechanical technologies discovered centuries ago by diverse sectors are implemented by well engineers. In petroleum industry, the ancient tube forming manufacturing process founds an application once well engineers intend to produce from reservoirs that cannot be reached unless previous and shallower troublesome formations are isolated. Solid expandable tubular is, for instance, one of those technologies developed to mitigate drilling problems and optimize the well delivery process. It consists of in-situ expansion of a steel-based tube that is attained by pushing/pulling a solid mandrel, which permanently enlarge its diameters. This non-linear expansion process is strongly affected by the material properties of the tubular, its geometry, and the pipe/mandrel contact surface. The anticipated force required to deform long sections of the pipe in an uncontrollable expansion environment, might jeopardize mechanical properties of the pipe and the well structural integrity. Scientific-based solutions, that depend on sound theoretical formulation and are validated through experiments, will help to understand possible tubular failure mechanisms during its operational life. This work is aimed to study the effect of different loading/boundary conditions on mechanical/physical properties of the pipe after expansion. First, full-scale experiments were conducted to evaluate the geometrical and behavioral changes. Second, simulation of deformation

Compact water depth sensor with LPFG using the photoelastic effect and heat-shrinkable tube

Science.gov (United States)

Takama, Shinya; Kudomi, Takamasa; Ohashi, Masaharu; Miyoshi, Yuji

2011-12-01

We propose a compact water depth sensor with a long period fiber grating (LPFG) using a heat-shrinkable tube. The pressure property of the LPFG is investigated experimentally to confirm the feasibility of the water depth sensor. Moreover, the water depth in the 2m long water-filled pipe is successfully estimated by the proposed water sensors.

On the computer simulation of LMFBR piping systems

International Nuclear Information System (INIS)

A-Moneim, M.T.; Chang, Y.-W.; Fistedis, S.H.

1977-01-01

A two-dimensional coupled hydrodynamic-structural response analysis of piping systems is described. Implicit Continuous-Fluid Eulerian (ICE) technique is utilized in the hydrodynamics while a finite-element technique is used in the structural analysis. Different piping components such as elbows, valves, reducers, expansions, heat exchangers, and tees are modelled and coupled with the straight pipe model. An axisymmetric general component model that can be used in modelling valves, reducers, expansions, and heat exchangers is described. At the inlet and outlet region of such component the cross-sectional area may change suddently or gradually, or many not change at all. Among the options available in this model are deformable exterior walls, interior rigid wall simulation, and tube bundle effect. Exterior walls of pipes and components are treated as thin axisymmetric shell. A convected coordinate explicit finite-element scheme for large displacement small strain, elastic-plastic material behavior in which membrane and bending strengths are accounted for is employed. The strains are linearly related to the displacement of the element relative to its convective coordinates, and similarly, the nodal forces are linearly related to the elements stresses. The coupling of the hydrodynamics and structural problems is done in such a way that the hydrodynamics supplies the structure with a pressure loading and the structure supplying the hydrodynamics with a moving boundary condition. Because of the difficulties of handling interior walls that may occupy partial zones, the walls are assumed rigid and limited in their orientation to be parallel to the radial or axial directions, their position to zone boundaries, and their thickness to zero

Study on pressure pulsation and piping vibration of complex piping of reciprocating compressor

International Nuclear Information System (INIS)

Xu Bin; Feng Quanke; Yu Xiaoling

2008-01-01

This paper presents a preliminary research on the piping vibration and pressure pulsation of reciprocating compressor piping system. On the basis of plane wave theory, the calculation of gas column natural frequency and pressure pulsation in complex pipelines is done by using the transfer matrix method and stiffness matrix method, respectively. With the discretization method of FEM, a mathematical model for calculating the piping vibration and stress of reciprocating compressor piping system is established, and proper boundary conditions are proposed. Then the structural modal and stress of the piping system are calculated with CAESAR II. The comparison of measured and calculated values found that the one dimensional wave equation can accurately calculate the natural frequency and pressure pulsation in gas column of piping system for reciprocating compressor. (authors)

Temperature control of paddy bulk storage with aeration-thermosyphon heat pipe

International Nuclear Information System (INIS)

Dussadee, Natthawud; Punsaensri, Tammasak; Kiatsiriroat, Tanongkiat

2007-01-01

A technology of an aeration-thermosyphon heat pipe is developed for controlling paddy temperature in a paddy bulk silo. A prototype of paddy bulk storage of 1000 kg has a set of copper tubes with steel fins embedded in the paddy bed. The total heat transfer area of the tubes with fins is 16 m 2 . The tubes act as the evaporator of a thermosyphon heat pipe and absorb heat resulting from the paddy respiration. The thermosyphon has a total condenser area of 12.2 m 2 that is exposed to ambient air. At the bottom of the silo, ambient air is fed upward through the paddy bed for the aeration. The initial moisture content of the paddy is around 12.8% wet basis. A mathematical model to predict the paddy bed temperature in the silo with the hybrid aeration-thermosyphon is developed, and the results agree very well with the experimental data. The operating period of its blower could be found from the simulation. The blower is on when the paddy bed temperature, T b , is over or equal to 28 deg. C and the difference temperature between the bed and the ambient, T d , is over or equal to 1 deg. C. The appropriate evaporator area should be over 8 m 2 . At the area of 8 m 2 , the operation time of the blower is 8-9% of the annual period compared with 30-40% for normal aeration alone. The monthly paddy bed temperature could be maintained between 24 and 27 deg. C under the climate of Chiang Mai, Thailand

77 FR 20782 - Circular Welded Carbon Steel Pipes and Tubes From Thailand: Preliminary Results of Antidumping...

Science.gov (United States)

2012-04-06

... Memorandum. We revised Pacific Pipe's financial expense ratio calculation to be based on its consolidated financial statements rather than its unconsolidated financial statements as reported. We increased Pacific... Saha Thai's financial expense ratio to zero. For more information on the changes to Saha Thai's COP...

Status of FRJ-2 refurbishment of tank pipes and essential results of aging analysis

International Nuclear Information System (INIS)

Hansen, G.; Thamm, G.; Thome, M.

1993-01-01

An aging evaluation program for FRJ-2 (DIDO) of the Forschungszentrum Juelich GmbH has been developed and is currently executed in cooperation with the licensing and regulatory and TUV experts in order to determine the overall life expectancy of the facility and to identify critical systems and components that need to be upgraded or refurbished for future safe reactor operation. In Phase A (completed) a so called master list of the FRJ-2 mechanical, electrical and structural components was compiled on a system-by system basis and the operational documentation with respect to regular inspections, maintenance, repair and unusual occurences was carefully examined. Critical components were selected and their ageing respectively life limiting mechanisms identified. In Phase (currently under way) special inspections, examinations and tests for critical systems/components are being elaborated, executed and evaluated. Current work is being concentrated on non replaceable components (e.g. reactor aluminium tank (RAT) and the connecting pipes to the primary cooling circuit, the reactor steel tank and pipe work inside the concrete reactor block). As a consequence of first results of the aging evaluation program and due to leaks in the weir and drain pipes of the RAT a repair/refurbishment program was set up for the Al-RAT pipes (risers, downcomers weir and drain pipes) and the steel guide tubes. Details of the r/r program which is in far progress and first essential results of the aging evaluation will be presented. The results achieved until today are encouraging with respect to safe reactor operation on short and medium term. (author)

Status of FRJ-2 Refurbishment of tank pipes and essential results of aging analysis

International Nuclear Information System (INIS)

Hansen, G.; Thamm, G.; Thome, M.

1994-01-01

An aging evaluation program for FRJ-2 (DIDO) of the Forschungszentrum Juelich GmbH has been developed and is currently executed in cooperation with the licensing and regulatory and TUEV experts in order to determine the overall life expectancy of the facility and to identify critical systems and components that need to be upgraded or refurbished for future safe reactor operation. In Phase A (completed) a so called master list of the FRJ-2 mechanical, electrical and structural components was compiled on a system-by system basis and the operational documentation with respect to regular inspections, maintenance, repair and unusual occurrences was carefully examined. Critical components were selected and their ageing respectively life limiting mechanisms identified. In Phase B (currently under way) special inspections, examinations and tests for critical systems/components are being elaborated, executed and evaluated. Current work is being concentrated on non replaceable components (e.g. reactor aluminium tank (RAT) and the connecting pipes to the primary cooling circuit, the reactor steel tank and pipe work inside the concrete reactor block). As a consequence of first results of the aging evaluation program and due to leaks in the weir and drain pipes of the RAT a repair/refurbishment program was set up for the Al-RAT pipes (risers, downcomers, weir and drain pipes) and the steel guide tubes. Details of the r/r program which is in far progress and first essential results of the aging evaluation will be presented. The results achieved until today are encouraging with respect to safe reactor operation on short and medium term. (J.P.N.)

77 FR 72818 - Circular Welded Carbon Steel Pipes and Tubes From Turkey; Final Results of Antidumping Duty...

Science.gov (United States)

2012-12-06

... description outlined above are included in the scope of this order, except for line pipe, oil country tubular... Analysts, through Robert James, Program Manager, entitled ``Final Results in the 2010/2011 Administrative...

Using of Multiwall Carbon Nanotube Based Nanofluid in the Heat Pipe to Get Better Thermal Performance

Directory of Open Access Journals (Sweden)

Y. Bakhshan

2014-09-01

Full Text Available Thermal performance of a cylindrical heat pipe is investigated numerically. Three different types of water based nanofluids, namely, Al2O3 + Water, Diamond + Water, and Multi-Wall Carbon Nano tube (MWCNT + Water, have been used. The influence of using the simple nanofluids and MWCNT nanofluid on the heat pipe characteristics such as liquid velocity, pressure profile, temperature profile, thermal resistance, and heat transfer coefficient of heat pipe has been studied. A new correlation developed by Bakhshan and Saljooghi (2014 for viscosity of nanofluids has been implemented. The results show, a good agreement with the available analytical and experimental data. Also the results show, that the MWCNT based nanofluid has lower thermal resistance, higher heat transfer coefficient, and lower temperature difference between evaporator and condenser sections, so it has good thermal specifications as a working fluid for use in heat pipes. The prepared code has capability for parametric studies also.

Experience of measuring wall thicknesses of district heating pipes in use with free-floating salamanders (pigs)

International Nuclear Information System (INIS)

Barbian, O.A.; Goedecke, H.; Krieg, W.

1992-01-01

A test system for district heating pipes (laid above ground or in the ground or in the offshore field) is introduced, a so-called 'intelligent' test 'pig' which, like in a pneumatic tube, floats through the pipe with the medium during operation and finds out any corrosion damage. The equipment works on the principle of ultrasonic wall thickness testing in immersed technique, and is equipped with a large number of test heads in order to scan the pipe surface completely in one run-through. The data processing in the pig with the aid of microprocessors and the type of data collection in mass memories is briefly described. The test results are clearly shown by coloured graphics, which makes efficient assessment and evaluation of the faults possible. The ability of the system to supply information (data collection, data storage, assessment and evaluation) is demonstrated by a series of typical faults, which were found worldwide in oil and gas pipes. (orig./HP) [de

Misleading Claims About Tobacco Products in YouTube Videos: Experimental Effects of Misinformation on Unhealthy Attitudes.

Science.gov (United States)

Albarracin, Dolores; Romer, Daniel; Jones, Christopher; Hall Jamieson, Kathleen; Jamieson, Patrick

2018-06-29

Recent content analyses of YouTube postings reveal a proliferation of user generated videos with misleading statements about the health consequences of various types of nontraditional tobacco use (eg, electronic cigarettes; e-cigarettes). This research was aimed at obtaining evidence about the potential effects of YouTube postings about tobacco products on viewers' attitudes toward these products. A sample of young adults recruited online (N=350) viewed one of four highly viewed YouTube videos containing misleading health statements about chewing tobacco, e-cigarettes, hookahs, and pipe smoking, as well as a control YouTube video unrelated to tobacco products. The videos about e-cigarettes and hookahs led to more positive attitudes toward the featured products than did control videos. However, these effects did not fully translate into attitudes toward combustive cigarette smoking, although the pipe video led to more positive attitudes toward combustive smoking than did the chewing and the hookah videos, and the e-cigarette video led to more positive attitudes toward combustive cigarette smoking than did the chewing video. This research revealed young people's reactions to misleading claims about tobacco products featured in popular YouTube videos. Policy implications are discussed. ©Dolores Albarracin, Daniel Romer, Christopher Jones, Kathleen Hall Jamieson, Patrick Jamieson. Originally published in the Journal of Medical Internet Research (http://www.jmir.org), 29.06.2018.

X-ray tube monitor apparatus

International Nuclear Information System (INIS)

Holland, W.P.; Pellergrino, A.

1981-01-01

An x-ray tube with a rotating anode target is provided with a detector of x-rays located outside a port of a housing of the tube and positioned at or near a tangent line to the radiating surface for observing variations in the radiation intensity due to rotation of the target, the variations being pronounced due to the heel effect of the radiation pattern. The x-ray detector can employ a scintillation material and be coupled by a light guide to a photodetector which is removed from the path of the radiation and detects scintillations of the x-ray detector. Alternatively, the photodetector and light pipe may be replaced by a detector of germanium, silicon or an ion chamber which converts x-ray photons directly to an electric current. An electronic unit determines the speed of rotation from the electric signal and can also, by fourier transform and signature analysis techniques, monitor the state of the radiating surface. (author)

78 FR 22515 - Seamless Refined Copper Pipe and Tube From Mexico: Rescission, in Part, of Antidumping Duty...

Science.gov (United States)

2013-04-16

... DEPARTMENT OF COMMERCE International Trade Administration [A-201-838] Seamless Refined Copper Pipe... Administration, International Trade Administration, Department of Commerce. DATES: Effective Date: April 16, 2013..., Import Administration, International Trade Administration, U.S. Department of Commerce, 14th Street and...

Subprogram Calculating The Distance Between Pipe And Plane For Automatic Piping System Design

International Nuclear Information System (INIS)

Satmoko, Ari

2001-01-01

DISTLNPL subprogram was created using Auto LISP software. This subprogram is planned to complete CAPD (Computer Aided Piping Design) software being developed. The CAPD works under the following method: suggesting piping system line and evaluating whether any obstacle allows the proposed line to be constructed. DISTLNPL is able to compute the distance between pipe and any equipment having plane dimension such as wall, platform, floors, and so on. The pipe is modeled by using a line representing its axis, and the equipment is modeled using a plane limited by some lines. The obtained distance between line and plane gives information whether the pipe crosses the equipment. In the case of crashing, the subprogram will suggest an alternative point to be passed by piping system. So far, DISTLNPL has not been able to be accessed by CAPD yet. However, this subprogram promises good prospect in modeling wall, platform, and floors

Visualization of the boiling phenomena and counter-current flow limit of annular heat pipe

Energy Technology Data Exchange (ETDEWEB)

Kim, In Guk; Kim, Kyung Mo; Jeong, Yeong Shin; Bang, In Cheol [UNIST, Ulsan (Korea, Republic of)

2015-10-15

The thermal resistance of conventional heat pipes increases over the capillary limit because of the insufficient supplement of the working fluid. Due to the shortage of the liquid supplement, thermosyphon is widely used for vertically oriented heat transport and high heat load conditions. Thermosyphons are two-phase heat transfer devices that have the highly efficient heat transport from evaporation to condensation section that makes an upward driving force for vapor. In the condenser section, the vapor condenses and releases the latent heat. Due to the gravitation force acting on the liquid in the tube, working fluid back to the evaporator section, normally this process operate at the vertical and inclination position. The use of two-phase closed thermosyphon (TPCT) for the cooling devices has the limitation due to the phase change of the working fluid assisted by gravity force. Due to the complex phenomenon of two-phase flow, it is required to understand what happened in TPCT. The visualization of the thermosyphon and heat pipe is investigated for the decrease of thermal resistance and enhancement of operation limit. Weibel et al. investigated capillary-fed boiling of water with porous sintered powder wick structure using high speed camera. At the high heat flux condition, dry-out phenomenon and a thin liquid film are observed at the porous wick structure. Wong and Kao investigated the evaporation and boiling process of mesh wicked heat pipe using optical camera. At the high heat flux condition, the water filing became thin and partial dry-out was observed in the evaporator section. Our group suggested the concept of a hybrid heat pipe with control rod as Passive IN-core Cooling System (PINCs) for decay heat removal for advanced nuclear power plant. The hybrid heat pipe is the combination of the heat pipe and control rod. It is necessary for PINCs to contain a neutron absorber (B{sub 4}C) to have the ability of reactivity control. It has annular vapor space and

Visualization of the boiling phenomena and counter-current flow limit of annular heat pipe

International Nuclear Information System (INIS)

Kim, In Guk; Kim, Kyung Mo; Jeong, Yeong Shin; Bang, In Cheol

2015-01-01

The thermal resistance of conventional heat pipes increases over the capillary limit because of the insufficient supplement of the working fluid. Due to the shortage of the liquid supplement, thermosyphon is widely used for vertically oriented heat transport and high heat load conditions. Thermosyphons are two-phase heat transfer devices that have the highly efficient heat transport from evaporation to condensation section that makes an upward driving force for vapor. In the condenser section, the vapor condenses and releases the latent heat. Due to the gravitation force acting on the liquid in the tube, working fluid back to the evaporator section, normally this process operate at the vertical and inclination position. The use of two-phase closed thermosyphon (TPCT) for the cooling devices has the limitation due to the phase change of the working fluid assisted by gravity force. Due to the complex phenomenon of two-phase flow, it is required to understand what happened in TPCT. The visualization of the thermosyphon and heat pipe is investigated for the decrease of thermal resistance and enhancement of operation limit. Weibel et al. investigated capillary-fed boiling of water with porous sintered powder wick structure using high speed camera. At the high heat flux condition, dry-out phenomenon and a thin liquid film are observed at the porous wick structure. Wong and Kao investigated the evaporation and boiling process of mesh wicked heat pipe using optical camera. At the high heat flux condition, the water filing became thin and partial dry-out was observed in the evaporator section. Our group suggested the concept of a hybrid heat pipe with control rod as Passive IN-core Cooling System (PINCs) for decay heat removal for advanced nuclear power plant. The hybrid heat pipe is the combination of the heat pipe and control rod. It is necessary for PINCs to contain a neutron absorber (B 4 C) to have the ability of reactivity control. It has annular vapor space and it

Elastic-plastic dynamic behavior of guard pipes due to sudden opening of longitudinal cracks in the inner pipe and crash to the guard pipe wall

International Nuclear Information System (INIS)

Theuer, E.; Heller, M.

1979-01-01

Integrity of guard pipes is an important parameter in the design of nuclear steam supply systems. A guard pipe shall withstand all kinds of postulated inner pipe breaks without failure. Sudden opening of a crack in the inner pipe and crash of crack borders to the guard pipe wall represent a shock problem where complex phenomena of dynamic plastification as well as dynamic behavior of the entire system have to be taken in consideration. The problem was analyzed by means of Finite Element computation using the general purpose program MARC. Equation of motion was resolved by direct integration using the Newmark β-operator. Analysis shows that after 1,2 m sec crack borders touch the guard pipe wall for the first time. At this moment a considerable amount of local plastification appears in the inner pipe wall, while the guard pipe is nearly unstressed. After initial touching, the crack borders begin to slip along the guard pipe wall. Subsequently, a short withdrawal of the crack borders and a new crash occur, while the inner pipe rolls along the guard pipe wall. The analysis procedure described is suitable for designing numerous guard pipe geometries as well as U-Bolt restraint systems which have to withstand high-energy pipe rupture impact. (orig.)

Pipe damping

International Nuclear Information System (INIS)

Ware, A.G.

1985-01-01

Studies are being conducted at the Idaho National Engineering Laboratory to determine whether an increase in the damping values used in seismic structural analyses of nuclear piping systems is justified. Increasing the allowable damping would allow fewer piping supports which could lead to safer, more reliable, and less costly piping systems. Test data from availble literature were examined to determine the important parameters contributing to piping system damping, and each was investigated in separate-effects tests. From the combined results a world pipe damping data bank was established and multiple regression analyses performed to assess the relative contributions of the various parameters. The program is being extended to determine damping applicable to higher frequency (33 to 100 Hz) fluid-induced loadings. The goals of the program are to establish a methodology for predicting piping system damping and to recommend revised guidelines for the damping values to be included in analyses

76 FR 78612 - Certain Welded Carbon Steel Standard Pipes and Tubes From India: Rescission of Antidumping Duty...

Science.gov (United States)

2011-12-19

... Corporation, we initiated reviews of Arihant Domestic Appliances Ltd., Good Luck Steel Tubes Ltd. and all affiliates, Good Luck Industries, Innoventive Industries Ltd., Jindal Group and all affiliates, Jindal... for a review of the order with respect to Arihant Domestic Appliances Ltd., Good Luck Steel Tubes Ltd...

Suggestion of an average bidirectional flow tube for the measurement of single and two phase flow rate

International Nuclear Information System (INIS)

Yun, B.J.; Kang, K.H.; Euh, D.J.; Song, C.H.; Baek, W.P.

2005-01-01

Full text of publication follows: A new type instrumentation, average bidirectional flow tube, was suggested to apply to the single and two phase flow condition. Its working principle is similar to that of the Pitot tube. The pressure measured at the front of the flow tube is equal to the total pressure, while that measured at the rear tube is slightly less than static pressure of flow field due to the suction effect at the downstream. It gives an amplification effect of measured pressure difference at the flow tube. The proposed instrumentation has the characteristics that it could be applicable to low flow condition and measure bidirectional flow. It was tested in the air-water vertical and horizontal test sections which have 0.08 m inner diameter. The pressure difference across the average bidirectional flow tube, system pressure, average void fraction and injection phasic mass flow rates were measured on the measuring plane. Test was performed primarily in the single phase water and air flow condition to get the amplification factor k of the flow tube. The test was also performed in the air-water two phase flow condition and the covered flow regimes were bubbly, slug, churn turbulent flow in the vertical pipe and stratified flow in the horizontal pipe. In order to calculate the phasic and total mass flow rates from the measured differential pressure, Chexal drift-flux correlation and momentum exchange factor between the two phases were introduced. The test result shows that the suggested instrumentation with the measured void fraction, Chexal drift-flux correlation and Bosio and Malnes' momentum exchange model can predict the phasic mass flow rates within 15% error compared to the true values. A new momentum exchange model was also suggested and it gives up to 5% improvement of the measured mass flow rate compared to combination of Bosio and Malnes' momentum exchange model. (authors)

Pipe Crawler internal piping characterization system. Deactivation and decommissioning focus area. Innovative Technology Summary Report

International Nuclear Information System (INIS)

1998-02-01

Pipe Crawler reg-sign is a pipe surveying system for performing radiological characterization and/or free release surveys of piping systems. The technology employs a family of manually advanced, wheeled platforms, or crawlers, fitted with one or more arrays of thin Geiger Mueller (GM) detectors operated from an external power supply and data processing unit. Survey readings are taken in a step-wise fashion. A video camera and tape recording system are used for video surveys of pipe interiors prior to and during radiological surveys. Pipe Crawler reg-sign has potential advantages over the baseline and other technologies in areas of cost, durability, waste minimization, and intrusiveness. Advantages include potentially reduced cost, potential reuse of the pipe system, reduced waste volume, and the ability to manage pipes in place with minimal disturbance to facility operations. Advantages over competing technologies include potentially reduced costs and the ability to perform beta-gamma surveys that are capable of passing regulatory scrutiny for free release of piping systems

Transient Pressure Surges Due to Pipe Movement in an Oil Well Surpressions transitoires dues au mouvement des colonnes de tubes dans les puits.

Directory of Open Access Journals (Sweden)

Lubinski A.

2006-11-01

Full Text Available A pressure surge which could cause lost circulation, results from running a stand of drill pipe or a joint of casing into a hole. Similarly, a negative pressure surge, which could cause a blowout, results from pulling pipe from a hole. In past investigations, pressure surges were calculated on the basis of steady state flow. It is shown in this paper that this led to erroneous results. In thls investigation, pressure surges are calculated on the basis of transient wave propagation phenomena. A computer program was developed to that effect. Results are presented in :the first part of the paper, and the mathematics in the second. La descente d'une longueur de tiges ou d'un tube de casing dans le trou provoque une surpression pouvant entraîner des pertes de circulation. De même, la remontée des tiges provoque une surpression négative pouvant entraîner une éruption. Au cours des précédentes recherches, les surpressions étaient calculées pour des débits en régime permanent. Il est montré dans cet étude que les résultats ainsi obtenus ne sont pas exacts. Dans cette recherche, les calculs des surpressions sont basés sur le phénomène de propagation transitoire des ondes. Un programme de calcul sur ordinateur a été développé à cet effet. Les résultats sont présentés dans la première partie de cet article et les calculs font l'objet de la deuxième partie.

Field survey and laboratory tests on composite materials case of GRP (Glass Fiber Reinforced Polyester tubes for water suply

Directory of Open Access Journals (Sweden)

Radu Hariga

2013-09-01

Full Text Available In the Moldova land, were made two lines of water adduction, having 6000 m length and 40 m slope, or 1/150 slope. The water supply component tubes were disposed under the plant: The tubes are made of glass – reinforced thermosetting plastics (GRP. After about 180 days of operation, one of the lines showed severe deterioration of the quality pipe components. This paper deals with some laboratory tests in order to detect the failure cases of the pipelines components.

The development of an auto-sealing system using an electrically shrinkable tube under a low-pressure condition

Energy Technology Data Exchange (ETDEWEB)

Okano, Yoshihiro; Kitagawa, Takao [NKK Corp, Tsu, Mie (Japan); Shoji, Norio [NKK Corp., Yokohama (Japan); Namioka, Toshiyuki [Nippon Kokan Koji Corp., Yokohama (Japan). Research and Development Dept.; Komura, Minoru [Nitto Denko Corp., Fukaya, Saitama (Japan)

1997-04-01

This article describes the development of a system to create high quality, automatic sealing of field joints of polyethylene coated pipelines. The system uses a combination of an electrically heated shrinkable tube and a low-pressure chamber. The self-heating shrinkable tube includes electric heater wires that heat when connected to electricity. A method was developed to eliminate air trapped between the tube and the steel pipe by shrinking the tube under a low-pressure condition. The low-pressure condition was automatic and easily attained by using a vacuum chamber. It was verified that the system produced high quality sealing of the field joints.

Pipe connector

International Nuclear Information System (INIS)

Sullivan, T.E.; Pardini, J.A.

1978-01-01

A safety test facility for testing sodium-cooled nuclear reactor components includes a reactor vessel and a heat exchanger submerged in sodium in the tank. The reactor vessel and heat exchanger are connected by an expansion/deflection pipe coupling comprising a pair of coaxially and slidably engaged tubular elements having radially enlarged opposed end portions of which at least a part is of spherical contour adapted to engage conical sockets in the ends of pipes leading out of the reactor vessel and in to the heat exchanger. A spring surrounding the pipe coupling urges the end portions apart and into engagement with the spherical sockets. Since the pipe coupling is submerged in liquid a limited amount of leakage of sodium from the pipe can be tolerated

Condensation driven water hammer studies for feed water distribution pipe

International Nuclear Information System (INIS)

Savolainen, S.; Katajala, S.; Elsing, B.; Nurkkala, P.; Longvinov, S.A.; Trunov, N.B.; Sitnik, Yu.K.

1997-01-01

Special T-shaped feedwater distribution pipes were installed in steam generators at the Loviisa (Finland) and Rovno (Russia) nuclear power plants. The new shape was tested in an extensive testing programme. Since the tubes frequently suffer from corrosion damage, large-scale water hammer experiments were performed on a model facility in 1996. The main objectives of the water hammer experiments were to find out the prevailing parameters leading to water hammers, as well as the sensitivity of hammering to boundary conditions. A water hammer may occur when the mass flow rate into the steam generator exceeds 6 kg/s and the temperature difference between steam generator and feedwater exceeds 100 degC. Visual experiments and stress analyses of the pipe were also carried out. The weakest part, the T-joint, may hold against such water hammers only for a limited time of the order of few minutes. (M.D.)

CT image reconstruction of steel pipe section from few projections using the method of rotating polar-coordinate

International Nuclear Information System (INIS)

Peng Shuaijun; Wu Zhifang

2008-01-01

Fast online inspection in steel pipe production is a big challenge. Radiographic CT imaging technology, a high performance non-destructive testing method, is quite appropriate for inspection and quality control of steel pipes. The method of rotating polar-coordinate is used to reconstruct the steel pipe section from few projections with the purpose of inspecting it online. It reduces the projection number needed and the data collection time, and accelerates the reconstruction algorithm and saves the inspection time evidently. The results of simulation experiment and actual experiment indicate that the image quality and reconstruction time of rotating polar-coordinate method meet the requirements of inspecting the steel tube section online basically. The study is of some theoretical significance and the method is expected to be widely used in practice. (authors)

Investigation and recovery of unrecovered fuel pellets and cladding tube pieces

International Nuclear Information System (INIS)

Kobayashi, Keiji

1980-01-01

The total weight of the fuel pellets lost due to break was about 1206 g, and cladding tube pieces were about 217 g. Among these, the pellets of about 527 g and the cladding tube pieces of about 152 g were recovered when broken fuel rods were discovered. It is not desirable to leave these broken pieces as unrecovered in view of safety and the management of nuclear fuel materials. Kansai Electric Power Co., Inc., investigated the position and the amount of these pellets and cladding tube pieces for about a year, and recovered a part of them. The results were written in two reports. The objects of the investigation and recovery, and the method of recovery are explained. The UO 2 and zirconium recovered were 58.52 g and 369.58 g, respectively. The solid pellets were recovered from the reactor, fuel assemblies, a spent fuel pit and canals, and the content in sludge was recovered from other installations. The amounts of unrecovered pellets and cladding tube pieces in primary cooling water, coolant filters, sealing water filters, primary cooling pipes, waste resins and fuel assemblies were estimated. The problems concerning the recovery and estimation are pointed out. The results of estimating the amount of uranium in coolant filters and sealing water filters are useful to know the time of the occurrence of accident. (Kako, I.)

The thermal performance of a loop-type heat pipe for passively removing residual heat from spent fuel pool

Energy Technology Data Exchange (ETDEWEB)

Xiong, Zhenqin [School of Nuclear Science and Engineering, Shanghai Jiao Tong University, No. 800 Dongchuan Road, Shanghai 200240 (China); Gu, Hanyang, E-mail: guhanyang@stu.edu.cn [School of Nuclear Science and Engineering, Shanghai Jiao Tong University, No. 800 Dongchuan Road, Shanghai 200240 (China); Wang, Minglu [School of Nuclear Science and Engineering, Shanghai Jiao Tong University, No. 800 Dongchuan Road, Shanghai 200240 (China); Cheng, Ye [Shanghai Nuclear Engineering Research and Design Institute, Shanghai 200233 (China)

2014-12-15

Highlights: • Feasibility of applying loop-type heat pipes for SFP is studied. • The heat transfer rate of the heat pipes was tested. • The heat transfer coefficient was between 200 and 490 W/m{sup 2}/s. • The effect of the water temperature is dominant. • Three kinds of the filling ratio 27%, 21% and 14% are compared. - Abstract: Heat pipe is an efficient heat transfer device without electrically driven parts. Therefore large-scale loop type heat pipe systems have potential uses for passively removing heat from spent fuel pools and reactor cores under the accidental conditions to improve the safety of the nuclear power station. However, temperature difference between the hot water in the spent fuel pool and the ambient air which is the heat sink is small, in the range of 20–60 °C. To understand and predict the heat removal capacity of such a large scale loop type heat pipe in the situation similar to the accidental condition of the spent fuel pool (SFP) for the design purpose, a loop-type heat pipe with a very high and large evaporator has been fabricated and was tested using ammonia as the working fluid. The evaporator with inner diameter of 65 mm and length of 7.6 m is immersed in a hot water tube which simulate the spent fuel pool. The condenser of the loop-type heat pipe is cooled by the air. The tests were performed with the velocity of the hot water in the tube in the range of 0.7–2.1 × 10{sup −2} m/s, the hot water inlet temperature between 50 and 90 °C and the air velocity ranging from 0.5 m/s to 2.5 m/s. Three kinds of the ammonia volumetric filling ratio in the heat pipe were tested, i.e. 27%, 21% and 14%. It is found that the heat transfer rate was in the range of 1.5–14.9 kW, and the heat transfer coefficient of evaporator was between 200 and 490 W/m{sup 2}/s. It is feasible to use the large scale loop type heat pipe to passively remove the residual heat from SFP. Furthermore, the effect of air velocity, air temperature, water flow

The thermal performance of a loop-type heat pipe for passively removing residual heat from spent fuel pool

International Nuclear Information System (INIS)

Xiong, Zhenqin; Gu, Hanyang; Wang, Minglu; Cheng, Ye

2014-01-01

Highlights: • Feasibility of applying loop-type heat pipes for SFP is studied. • The heat transfer rate of the heat pipes was tested. • The heat transfer coefficient was between 200 and 490 W/m 2 /s. • The effect of the water temperature is dominant. • Three kinds of the filling ratio 27%, 21% and 14% are compared. - Abstract: Heat pipe is an efficient heat transfer device without electrically driven parts. Therefore large-scale loop type heat pipe systems have potential uses for passively removing heat from spent fuel pools and reactor cores under the accidental conditions to improve the safety of the nuclear power station. However, temperature difference between the hot water in the spent fuel pool and the ambient air which is the heat sink is small, in the range of 20–60 °C. To understand and predict the heat removal capacity of such a large scale loop type heat pipe in the situation similar to the accidental condition of the spent fuel pool (SFP) for the design purpose, a loop-type heat pipe with a very high and large evaporator has been fabricated and was tested using ammonia as the working fluid. The evaporator with inner diameter of 65 mm and length of 7.6 m is immersed in a hot water tube which simulate the spent fuel pool. The condenser of the loop-type heat pipe is cooled by the air. The tests were performed with the velocity of the hot water in the tube in the range of 0.7–2.1 × 10 −2 m/s, the hot water inlet temperature between 50 and 90 °C and the air velocity ranging from 0.5 m/s to 2.5 m/s. Three kinds of the ammonia volumetric filling ratio in the heat pipe were tested, i.e. 27%, 21% and 14%. It is found that the heat transfer rate was in the range of 1.5–14.9 kW, and the heat transfer coefficient of evaporator was between 200 and 490 W/m 2 /s. It is feasible to use the large scale loop type heat pipe to passively remove the residual heat from SFP. Furthermore, the effect of air velocity, air temperature, water flow rate and

Water-hammer in the feed-water pipes for PWR steam generators

International Nuclear Information System (INIS)

Gonnet, Bernard; Leroy, Claude; Oullion, Jean; Yazidjian, J.-C.

1979-01-01

PWR boiler water feed pipes have been known for several years to be affected by violent water-hammer during start-ups and operation of the plant. In view of the varying results of corrective design modifications in America and Europe, FRAMATOME undertook an experimental research programme which resulted in the adoption of cruciform tubes on the feed-water distributor as the most reliable solution. Subsequent tests at Fessenheim I confirmed the effectiveness of this device [fr

Characterization of pipes, drain lines, and ducts using the pipe explorer system

International Nuclear Information System (INIS)

Cremer, C.D.; Kendrick, D.T.; Cramer, E.

1997-01-01

As DOE dismantles its nuclear processing facilities, site managers must employ the best means of disposing or remediating hundreds of miles of potentially contaminated piping and duct work. Their interiors are difficult to access, and in many cases even the exteriors are inaccessible. Without adequate characterization, it must be assumed that the piping is contaminated, and the disposal cost of buried drain lines can be on the order of $1,200/ft and is often unnecessary as residual contamination levels often are below free release criteria. This paper describes the program to develop a solution to the problem of characterizing radioactive contamination in pipes. The technical approach and results of using the Pipe Explorer trademark system are presented. The heart of the system is SEA's pressurized inverting membrane adapted to transport radiation detectors and other tools into pipes. It offers many benefits over other pipe inspection approaches. It has video and beta/gamma detection capabilities, and the need for alpha detection has been addressed through the development of the Alpha Explorer trademark. These systems have been used during various stages of decontamination and decommissioning of DOE sites, including the ANL CP-5 reactor D ampersand D. Future improvements and extensions of their capabilities are discussed

HPFRCC - Extruded Pipes

DEFF Research Database (Denmark)

Stang, Henrik; Pedersen, Carsten

1996-01-01

The present paper gives an overview of the research onHigh Performance Fiber Reinforced Cementitious Composite -- HPFRCC --pipes recently carried out at Department of Structural Engineering, Technical University of Denmark. The project combines material development, processing technique development......-w$ relationship is presented. Structural development involved definition of a new type of semi-flexiblecement based pipe, i.e. a cement based pipe characterized by the fact that the soil-pipe interaction related to pipe deformation is an importantcontribution to the in-situ load carrying capacity of the pipe...

Experimental study on heat pipe heat removal capacity for passive cooling of spent fuel pool

International Nuclear Information System (INIS)

Xiong, Zhenqin; Wang, Minglu; Gu, Hanyang; Ye, Cheng

2015-01-01

Highlights: • A passively cooling SFP heat pipe with an 8.2 m high evaporator was tested. • Heat removed by the heat pipe is in the range of 3.1–16.8 kW. • The heat transfer coefficient of the evaporator is 214–414 W/m 2 /K. • The heat pipe performance is sensitive to the hot water temperature. - Abstract: A loop-type heat pipe system uses natural flow with no electrically driven components. Therefore, such a system was proposed to passively cool spent fuel pools during accidents to improve nuclear power station safety especially for station blackouts such as those in Fukushima. The heat pipe used for a spent fuel pool is large due to the spent fuel pool size. An experimental heat pipe test loop was developed to estimate its heat removal capacity from the spent fuel pool during an accident. The 7.6 m high evaporator is heated by hot water flowing vertically down in an assistant tube with a 207-mm inner diameter. R134a was used as the potential heat pipe working fluid. The liquid R134a level was 3.6 m. The tests were performed for water velocities from 0.7 to 2.1 × 10 −2 m/s with water temperatures from 50 to 90 °C and air velocities from 0.5 m/s to 2.5 m/s. The results indicate significant heat is removed by the heat pipe under conditions that may occur in the spent fuel pool

Crack growth rate of PWR piping

International Nuclear Information System (INIS)

Bethmont, M.; Doyen, J.J.; Lebey, J.

1979-01-01

The Aquitaine 1 program, carried out jointly by FRAMATOME and the CEA is intended to improve knowledge about cracking mechanisms in AISI 316 L austenitic stainless steel under conditions similar to those of the PWR environment (irradiation excluded). Experiments of fatigue crack growth are performed on piping elements, scale 1/4 of primary pipings, by means of internal hydraulic cyclic pressure. Interpretation of results requires a knowledge of the stress intensity factor Ksub(I) at the front of the crack. Results of a series of calculations of Ksub(I) obtained by different methods for defects of finite and infinite length (three dimensional calculations) are given in the paper. The following have been used: calculations by finite elements, calculations by weight function. Notches are machined on the test pipes, which are subjected to internal hydraulic pressure cycles, under cold conditions, to initiate a crack at the tip of the notch. They are then cycled at a frequency of 4 cycles/hour on on water demineralised loop at a temperature of 280 0 C, the pressure varying at each cycle between approximately 160 bars and 3 bars. After each test, a specimen containing the defect is taken from the pipe for micrographic analysis. For the first test the length of the longitudinal external defect is assumed infinite. The number of cycles carried out is 5880 cycles. Two defects are machined in the tube for the second test. The number of cycles carried out is N = 440. The tests are performed under hot conditions (T = 280 0 C). For the third test two defects are analysed under cold and hot conditions. The number of cycles carried out for the external defect is 7000 when hot and 90000 when cold. The number of cycles for the internal defect is 1650 when hot and 68000 when cold. In order to interpret the results, the data da/dN are plotted on a diagram versus ΔK. Comparisons are made between these results and the curves from laboratory tests

Mathematical modeling of the dynamic stability of fluid conveying pipe based on integral equation formulations

International Nuclear Information System (INIS)

Elfelsoufi, Z.; Azrar, L.

2016-01-01

In this paper, a mathematical modeling of flutter and divergence analyses of fluid conveying pipes based on integral equation formulations is presented. Dynamic stability problems related to fluid pressure, velocity, tension, topography slope and viscoelastic supports and foundations are formulated. A methodological approach is presented and the required matrices, associated to the influencing fluid and pipe parameters, are explicitly given. Internal discretizations are used allowing to investigate the deformation, the bending moment, slope and shear force at internal points. Velocity–frequency, pressure-frequency and tension-frequency curves are analyzed for various fluid parameters and internal elastic supports. Critical values of divergence and flutter behaviors with respect to various fluid parameters are investigated. This model is general and allows the study of dynamic stability of tubes crossed by stationary and instationary fluid on various types of supports. Accurate predictions can be obtained and are of particular interest for a better performance and for an optimal safety of piping system installations. - Highlights: • Modeling the flutter and divergence of fluid conveying pipes based on RBF. • Dynamic analysis of a fluid conveying pipe with generalized boundary conditions. • Considered parameters fluid are the pressure, tension, slopes topography, velocity. • Internal support increase the critical velocity value. • This methodologies determine the fluid parameters effects.

Simulation of ratcheting in straight pipes using ANSYS with an improved cyclic plasticity model

International Nuclear Information System (INIS)

Hassan, T.; Zhu, Y.; Matzen, V.C.

1996-01-01

Ratcheting has been shown to be a contributing cause of failure in several seismic experiments on piping components and systems. Most commercial finite element codes have been unable to simulate the ratcheting in those tests accurately. The reason for this can be traced to inadequate plasticity constitutive models in the analysis codes. The authors have incorporated an improved cyclic plasticity model, based on an Armstrong-Frederick kinematic hardening rule in conjunction with the Drucker-Palgen plastic modulus equation, into an ANSYS user subroutine. This modified analysis code has been able to simulate quite accurately the ratcheting behavior of a tube subjected to a constant internal pressure and axially strain controlled cycling. This paper describes simulations obtained form this modified ANSYS code for two additional tests: (1) a tube subjected to constant axial stress and prescribed torsional cycling, and (2) a straight pipe subjected to constant internal pressure and quasi-static cyclic bending. The analysis results from the modified ANSYS code are compared to the experimental data, as well as results from ABAQUS and the original ANSYS code. The resulting correlation shows a significant improvement over the original ANSYS and the ABAQUS codes

Numerical Simulation Analysis of Five-Step Variable-Diameter Pipe with Solid-Liquid Two-Phase Abrasive Flow Polishing

Science.gov (United States)

Li, Junye; Zhang, Hengfu; Wu, Guiling; Hu, Jinglei; Liu, Yang; Sun, Zhihui

2018-01-01

In many areas of precision machining abrasive flow polishing technology has an important role. In order to study the influence of abrasive flow on the polishing effect of variable diameter parts, the fifth step variable diameter tube was taken as the research object to analyze the dynamic pressure and turbulent kinetic energy distribution of inlet velocity on the fifth-order variable diameter tube influences. Through comparative analysis, the abrasive flow polished variable diameter pipe parts have very effective and significant polishing effect and the higher the inlet speed, the more significant the polishing effect.

Pipe damping

International Nuclear Information System (INIS)

Ware, A.G.; Arendts, J.G.

1984-01-01

A program has been developed to assess the available piping damping data, to generate additional data and conduct seperate effects tests, and to establish a plan for reporting and storing future test results into a data bank. This effort is providing some of the basis for developing higher allowable damping values for piping seismic analyses, which will potentially permit removal of a considerable number of piping supports, particularly snubbers. This in turn will lead to more flexible piping systems which will be less susceptible to thermal cracking, will be easier to maintain and inspect, as well as less costly

Pipe rupture and steam/water hammer design loads for dynamic analysis of piping systems

International Nuclear Information System (INIS)

Strong, B.R. Jr.; Baschiere, R.J.

1978-01-01

The design of restraints and protection devices for nuclear Class I and Class II piping systems must consider severe pipe rupture and steam/water hammer loadings. Limited stress margins require that an accurate prediction of these loads be obtained with a minimum of conservatism in the loads. Methods are available currently for such fluid transient load development, but each method is severely restricted as to the complexity and/or the range of fluid state excursions which can be simulated. This paper presents a general technique for generation of pipe rupture and steam/water hammer design loads for dynamic analysis of nuclear piping systems which does not have the limitations of existing methods. Blowdown thrust loadings and unbalanced piping acceleration loads for restraint design of all nuclear piping systems may be found using this method. The technique allows the effects of two-phase distributed friction, liquid flashing and condensation, and the surrounding thermal and mechanical equipment to be modeled. A new form of the fluid momentum equation is presented which incorporates computer generated fluid acceleration histories by inclusion of a geometry integral termed the 'force equivalent area' (FEA). The FEA values permit the coupling of versatile thermal-hydraulic programs to piping dynamics programs. Typical applications of the method to pipe rupture problems are presented and the resultant load histories compared with existing techniques. (Auth.)

Feasibility evaluations for the integration of laser butt welding of tubes in industrial pipe coil production lines

Science.gov (United States)

Penasa, Mauro; Colombo, Enrico; Giolfo, Mauro

1994-09-01

Due to the good performance shown by laser welded joints, to the quality and repeatability achievable by this welding technique and to its high process productivity, a feature inherent to the laser technology which, together with its high flexibility, allows different operations to be performed by a single source, consistent savings in a production line may be obtained. Therefore laser welding techniques may be of high relevance for industrial applications, provided that a sufficient attention is paid to avoiding a low utilization time to the operating laser source. The paper describes a feasibility study for the integration of a laser source as an automatic unit for circumferential butt welding of tubes in production lines of pipe coils, just before the cold bending station. Using a 6 kW CO2 source, thickness ranging from 3.5 to 11.2 mm in carbon, low alloyed Cr-Mo and austenitic stainless steels, have been successfully welded. Cr-Mo steels require on line preheating treatment, which however can be achieved by laser defocused passes just before welding. The results of the preliminary qualification performed on laser welded joints of the involved topologies of product (materials, diameters and thicknesses) are described together with technological tests required for approval: laser circumferential butt welding of tubes has proven to be effective, with satisfactory and repeatable results and good joint performances. An exhaustive comparison with current welding techniques (TIG, MIG) is then carried out, along with a detailed analysis of the potential advantages and benefits which may be expected by using the laser welding technique, as well as with a first estimation of the investments and running costs. Since laser productivity is saturated only at a rough 35% during the year, an accurate analysis of other possible applications and of a possible lay out of a laser working cell integrated in the factory production lines is performed. Usually little attention is

Calculation of critical heat transfer in horizontal evaporator pipes in cooling systems of high-rise buildings

Science.gov (United States)

Aksenov, Andrey; Malysheva, Anna

2018-03-01

An exact calculation of the heat exchange of evaporative surfaces is possible only if the physical processes of hydrodynamics of two-phase flows are considered in detail. Especially this task is relevant for the design of refrigeration supply systems for high-rise buildings, where powerful refrigeration equipment and branched networks of refrigerants are used. On the basis of experimental studies and developed mathematical model of asymmetric dispersed-annular flow of steam-water flow in horizontal steam-generating pipes, a calculation formula has been obtained for determining the boundaries of the zone of improved heat transfer and the critical value of the heat flux density. A new theoretical approach to the solution of the problem of the flow structure of a two-phase flow is proposed. The applied method of dissipative characteristics of a two-phase flow in pipes and the principle of a minimum rate of entropy increase in stabilized flows made it possible to obtain formulas that directly reflect the influence of the viscous characteristics of the gas and liquid media on their distribution in the flow. The study showed a significant effect of gravitational forces on the nature of the phase distribution in the cross section of the evaporative tubes. At a mass velocity of a two-phase flow less than 700 kg / m2s, the volume content of the liquid phase near the upper outer generating lines of the tube is almost an order of magnitude lower than the lower one. The calculation of the heat transfer crisis in horizontal evaporative tubes is obtained. The calculated dependence is in good agreement with the experimental data of the author and a number of foreign researchers. The formula generalizes the experimental data for pipes with the diameter of 6-40 mm in the pressure of 2-7 MPa.

Measurement of 222Rn flux, 222Rn emanation and 226Ra concentration from injection well pipe scale

International Nuclear Information System (INIS)

Rood, A.S.; Kendrick, D.T.

1996-01-01

The presence of Naturally Occurring Radioactive Material (NORM) has been recognized since the early 1930s in petroleum reservoirs and in oil and gas production and processing facilities. NORM was typically observed in barite scale that accumulated on the interior of oil production tubing and in storage tank and heater-treater separation sludge. Recent concern has been expressed over the health impacts from the uncontrolled release of NORM to the public. There are several potential exposure pathways to humans from oil-field NORM. Among these is inhalation of radon gas and its daughter products. For this exposure pathway to be of any significance, radon must first be released from the NORM matrix and diffuse in free air. The radon emanation fraction refers to the fraction of radon atoms produced by the decay of radium, that migrate from the bulk material as free gaseous atoms. The purpose of this investigation was to characterize the radon release rates from NORM-scale contaminated production tubing being stored above ground, characterize the radon emanation fraction of the bulk scale material when removed from the tubing, and characterize the radium concentrations of the scale. Accurate characterization of 222 Rn emanation fractions from pipe scale may dictate the type of disposal options available for this waste. Characterization of radon release from stored pipes will assist in determining if controls are needed for workers or members of the public downwind from the source. Due to the sensitive nature of this data, the location of this facility is not disclosed

CAPD Software Development for Automatic Piping System Design: Checking Piping Pocket, Checking Valve Level and Flexibility

International Nuclear Information System (INIS)

Ari Satmoko; Edi Karyanta; Dedy Haryanto; Abdul Hafid; Sudarno; Kussigit Santosa; Pinitoyo, A.; Demon Handoyo

2003-01-01

One of several steps in industrial plant construction is preparing piping layout drawing. In this drawing, pipe and all other pieces such as instrumentation, equipment, structure should be modeled A software called CAPD was developed to replace and to behave as piping drafter or designer. CAPD was successfully developed by adding both subprogram CHKUPIPE and CHKMANV. The first subprogram can check and gives warning if there is piping pocket in the piping system. The second can identify valve position and then check whether valve can be handled by operator hand The main program CAPD was also successfully modified in order to be capable in limiting the maximum length of straight pipe. By limiting the length, piping flexibility can be increased. (author)

Pipe drafting and design

CERN Document Server

Parisher, Roy A

2011-01-01

Pipe Drafting and Design, Third Edition provides step-by-step instructions to walk pipe designers, drafters, and students through the creation of piping arrangement and isometric drawings. It includes instructions for the proper drawing of symbols for fittings, flanges, valves, and mechanical equipment. More than 350 illustrations and photographs provide examples and visual instructions. A unique feature is the systematic arrangement of drawings that begins with the layout of the structural foundations of a facility and continues through to the development of a 3-D model. Advanced chapters

Improved heat transfer on condensers with Ti tubes by means of granulate spheres

International Nuclear Information System (INIS)

Multer, I.

1985-01-01

Swedish power plants are located on the Baltic Sea coast and on the West coast. The cooling water is of high quality with low to medium impurity concentrations. In spite of this, pipe leakages occurred after a short period of operation, and the SoMs tubes had to be replaced by Ti tubes. Contrary to expectations, the heat transfer coefficient was higher by 10 to 20% with Ti tubes. This improvement is assumed to be due to the fact that Ti tube condensers are easier to clean by means of foamed rubber balls. As it was impossible to obtain a heat transfer coefficient of 100% with foamed rubber balls, experiments were carried out with granulate balls developed by Taprogge. In 6 series of experiments the overall heat transfer coefficient could be raised by 8%. Further experiments will follow. (orig.) [de

Insulated pipe clamp design

International Nuclear Information System (INIS)

Anderson, M.J.; Hyde, L.L.; Wagner, S.E.; Severud, L.K.

1980-01-01

Thin wall large diameter piping for breeder reactor plants can be subjected to significant thermal shocks during reactor scrams and other upset events. On the Fast Flux Test Facility, the addition of thick clamps directly on the piping was undesired because the differential metal temperatures between the pipe wall and the clamp could have significantly reduced the pipe thermal fatigue life cycle capabilities. Accordingly, an insulated pipe clamp design concept was developed. The design considerations and methods along with the development tests are presented. Special considerations to guard against adverse cracking of the insulation material, to maintain the clamp-pipe stiffness desired during a seismic event, to minimize clamp restraint on the pipe during normal pipe heatup, and to resist clamp rotation or spinning on the pipe are emphasized

Heat transfer of a helical double-pipe vertical evaporator: Theoretical analysis and experimental validation

Energy Technology Data Exchange (ETDEWEB)

Colorado-Garrido, D.; Santoyo-Castelazo, E. [Posgrado en Ingenieria y Ciencias Aplicadas, Universidad Autonoma del Estado de Morelos, Av. Universidad 1001. Col. Chamilpa, C.P. 62209 Cuernavaca, Morelos (Mexico); Hernandez, J.A.; Siqueiros, J.; Juarez-Romero, D. [Centro de Investigacion en Ingenieria y Ciencia Aplicadas, Universidad Autonoma del Estado de Morelos, Av. Universidad 1001. Col. Chamilpa, C.P. 62209 Cuernavaca, Morelos (Mexico); Garcia-Valladares, O. [Centro de Investigacion en Energia (CIE), Universidad Nacional Autonoma de Mexico(UNAM), Privada Xochicalco S/N, Temixco, 62580 Morelos (Mexico)

2009-07-15

A predictive model is developed to describe heat transfer and fluid dynamic behavior of a helical double-pipe vertical evaporator used in an absorption heat transformer integrated to a water purification process. The evaporator uses water as working fluid connected in countercurrent. Heat transfer by conduction in the internal tube wall is considered; in addition the change of phase is carried out into the internal tube. The dynamic model considers equations of continuity, momentum and energy in each flow. The discretized governing equations are coupled using an implicit step by step method. The results of this model are compared with the experimental data in steady state, obtaining good agreement in the evaporation process. The model is also evaluated of form dynamic to determine the principal operation variables that affect the evaporator with the main objective to optimize and control the system. (author)

Application of the leak-before-break concept to steam generator tubes

International Nuclear Information System (INIS)

Keim, E.; Kastner, W.

1994-01-01

The Leak-Before-Break (LBB) behaviour of a piping component means that the length of a crack resulting in a leak is smaller than the critical crack length and that the leak is safety detectable by a suitable monitoring system. The LBB-concept of Siemens/KWU is based on computer codes for the evaluation of critical crack lengths, crack openings, leakage areas and leakage rates, developed by Siemens/KWU. The fracture mechanics analysis supplies the input for the thermal-hydraulic analysis. The resulting leakage rate related to the crack length of a longitudinal or circumferential crack and the minimum detectable values of leakage rate and crack length lead to two criteria, which allow for the LBB-behaviour of the pipe: - the critical crack length must be larger than the crack length being safety detected by leakage monitoring systems (LMS) - the critical crack length must be larger than the crack length being safety detected by non-destructive examination (NDE). This LBB-concept is applied to steam generator (SG) tubes. Two examples, which will be presented, show that this concept is a very useful and effective tool which allows the prediction of LBB-behaviour of SG tubes. (Author)

Particle deposition from aqueous suspensions in turbulent pipe flow - a comparison of observed deposition rates and predicted arrival rates

International Nuclear Information System (INIS)

Rodliffe, R.S.

1979-11-01

At the present time, there appear to be only four adequately controlled and characterised experimental studies of particle deposition from single phase water in turbulent pipe flow. These are used to illustrate the ranges of applicability of methods for predicting particle arrival rates at tube walls. Arrival rates are predicted from mass transfer correlations and the theory of Reeks and Skyrme (1976) when transport is limited by Brownian diffusion and inertial behaviour, respectively. The regimes in which finite particle size limits the application of these methods are defined and preliminary consideration is given to the conditions under which gravitational settling may make a contribution to deposition in vertically mounted tubes. (author)

76 FR 36089 - Circular Welded Non-Alloy Steel Pipe From the Republic of Korea: Final Results of the Antidumping...

Science.gov (United States)

2011-06-21

... Tube From Brazil, the Republic of Korea, Mexico, and Venezuela, 61 FR 11608 (March 21, 1996), pipe...) (``Assessment Policy Notice''). This clarification will apply to entries of subject merchandise during the... transaction. See Assessment Policy Notice for a full discussion of this clarification. Cash Deposit...

Thermal performance comparison of oscillating heat pipes with and without helical micro-grooves

Science.gov (United States)

Qu, Jian; Li, Xiaojun; Xu, Qian; Wang, Qian

2017-11-01

This paper presents an experimental investigation to compare the thermal performance of three closed loop oscillating heat pipes (OHPs) with and without internal helical microgrooves at vertical and horizontal orientations. All of these OHPs were made from copper tubes and have three turns with lengths of 70, 230 and 110 mm at the evaporator, adiabatic and condenser sections, respectively. Deionized water was used as the working fluid at a volumetric filling ratio of 50%. The internal diameters (IDs) of two smooth-tube OHPs are 4.0 and 4.8 mm, respectively, and the internal diameter of micro-grooved OHP without groove structures is about 4.5 mm. Experimental results demonstrated that the addition of groove structures make the OHP remarkably outperform smooth-tube OHPs in both effective thermal conductivity and thermal resistance. The thermal resistance of vertically-oriented micro-grooved OHP could be lowered to 0.057 °C/W associated with an effective thermal conductivity of 6.1 × 104 W/ (m·K) at the input heat flux of 3.8 × 104 W/m2. Compared to smooth-tube OHPs, preliminary mechanism analysis reveals that local heat transfer coefficients both at the heating and cooling sections of micro-grooved OHP could be significantly improved. Moreover, enhanced liquid backflow to the evaporator due to microgroove-induced capillarity is also responsible for the OHP performance enhancement.

Management of in-tube projectiles using acoustic channel

Science.gov (United States)

Kostina, M. A.; Bortalevich, S. I.; Loginov, E. L.; Shinyakov, Y. A.; Sukhorukov, M. P.

2018-03-01

The article describes the method of measuring the distance from the operator's console installed outside the pipe to the in-tube projectile. A method for measuring distance in the absence of an echo signal is proposed. To do this, two identical ultrasonic locators operating at different frequencies were installed inside and outside the pipeline. The change in the duration of an acoustic pulse propagating in a circular waveguide with rigid walls is shown, which leads to a decrease in the data transfer rate.

Heat pipe

International Nuclear Information System (INIS)

Triggs, G.W.; Lightowlers, R.J.; Robinson, D.; Rice, G.

1986-01-01

A heat pipe for use in stabilising a specimen container for irradiation of specimens at substantially constant temperature within a liquid metal cooled fast reactor, comprises an evaporator section, a condenser section, an adiabatic section therebetween, and a gas reservoir, and contains a vapourisable substance such as sodium. The heat pipe further includes a three layer wick structure comprising an outer relatively fine mesh layer, a coarse intermediate layer and a fine mesh inner layer for promoting unimpeded return of condensate to the evaporation section of the heat pipe while enhancing heat transfer with the heat pipe wall and reducing entrainment of the condensate by the upwardly rising vapour. (author)

Fundamentals of piping design

CERN Document Server

Smith, Peter

2013-01-01

Written for the piping engineer and designer in the field, this two-part series helps to fill a void in piping literature,since the Rip Weaver books of the '90s were taken out of print at the advent of the Computer Aid Design(CAD) era. Technology may have changed, however the fundamentals of piping rules still apply in the digitalrepresentation of process piping systems. The Fundamentals of Piping Design is an introduction to the designof piping systems, various processes and the layout of pipe work connecting the major items of equipment forthe new hire, the engineering student and the vetera

Multiple-effect diffusion solar still coupled with a vacuum-tube collector and heat pipe

KAUST Repository

Chong, Tze-Ling; Huang, Bin-Juine; Wu, Po-Hsien; Kao, Yeong-Chuan

2014-01-01

The present study develops a multiple-effect diffusion solar still (MEDS) with a bended-plate design in multiple-effect diffusion unit (MDU) to solve the peel-off problem of wick material. The MDU is coupled with a vacuum-tube solar collector

A Multi-Dimensional Heat Transfer Model of a Tie-Tube and Hexagonal Fuel Element for Nuclear Thermal Propulsion

Science.gov (United States)

Gomez, C. F.; Mireles, O. R.; Stewart, E.

2016-01-01

The Space Capable Cryogenic Thermal Engine (SCCTE) effort considers a nuclear thermal rocket design based around a Low-Enriched Uranium (LEU) design fission reactor. The reactor core is comprised of bundled hexagonal fuel elements that directly heat hydrogen for expansion in a thrust chamber and hexagonal tie-tubes that house zirconium hydride moderator mass for the purpose of thermalizing fast neutrons resulting from fission events. Created 3D steady state Hex fuel rod model with 1D flow channels. Hand Calculation were used to set up initial conditions for fluid flow. The Hex Fuel rod uses 1D flow paths to model the channels using empirical correlations for heat transfer in a pipe. Created a 2-D axisymmetric transient to steady state model using the CFD turbulent flow and Heat Transfer module in COMSOL. This model was developed to find and understand the hydrogen flow that might effect the thermal gradients axially and at the end of the tie tube where the flow turns and enters an annulus. The Hex fuel rod and Tie tube models were made based on requirements given to us by CSNR and the SCCTE team. The models helped simplify and understand the physics and assumptions. Using pipe correlations reduced the complexity of the 3-D fuel rod model and is numerically more stable and computationally more time-efficient compared to the CFD approach. The 2-D axisymmetric tie tube model can be used as a reference "Virtual test model" for comparing and improving 3-D Models.

Analysis of a double-pipe heat exchanger performance using heat structure coupling of MARS and CUPID

International Nuclear Information System (INIS)

Amidua, M.; Kim, H.; Cho, H. K.

2015-01-01

Thermal hydraulic phenomena in the inner tube of the double-pipe heat exchanger are expected to be reproducible by one-dimensional system analysis codes (MARS) if a proper condensation heat transfer coefficient is applied. Jeon et al (2013) and Cho et al (2013) conducted comprehensive reviews of the predictive capability of the condensation heat transfer models for the steam-water stratified flow. On the contrary, in the outer tube, a multidimensional analysis tool is required to incorporate the influence of azimuthal angle on the heat transfer rate from the inner tube outer wall to the outer tube fluid. Therefore, a coupled calculation between one dimensional system analysis code and a multidimensional computational fluid dynamics code is an attainable way to predict this effect with a reliable accuracy. CUPID is a three-dimensional computational multiphase fluid dynamics code developed by KAERI (Korea Atomic Energy Research Institute). According to Jeong et al (2010), the objective of the development is to support a resolution for the thermal hydraulic issues regarding the transient multi-dimensional twophase phenomena which can arise in an advanced light water reactor. It uses two-fluid model for the governing equations, which uses two sets of Navier-Stokes' equations for two phases. It can be used as either a typical CFD code or a component code (porous CFD code) depending on the length scale of the phenomena that need to be resolved. On the other hand, MARS is a best estimate thermalhydraulic system code and it was developed at KAERI by consolidating and restructuring the RELAP5/MOD3.2 code and COBRA-TF code (Cho et al., 2014). The MARS code has the capability to analyze best-estimated thermal hydraulic system. In this study, the coupled CUPID-MARS code was used for the simulation of a double-pipe heat exchanger. This paper presents the description of the heat exchanger, the coupling method, and the simulation results using the coupled code. The coupling

Steady finite-Reynolds-number flows in three-dimensional collapsible tubes

Science.gov (United States)

Hazel, Andrew L.; Heil, Matthias

2003-07-01

A fully coupled finite-element method is used to investigate the steady flow of a viscous fluid through a thin-walled elastic tube mounted between two rigid tubes. The steady three-dimensional Navier Stokes equations are solved simultaneously with the equations of geometrically nonlinear Kirchhoff Love shell theory. If the transmural (internal minus external) pressure acting on the tube is sufficiently negative then the tube buckles non-axisymmetrically and the subsequent large deformations lead to a strong interaction between the fluid and solid mechanics. The main effect of fluid inertia on the macroscopic behaviour of the system is due to the Bernoulli effect, which induces an additional local pressure drop when the tube buckles and its cross-sectional area is reduced. Thus, the tube collapses more strongly than it would in the absence of fluid inertia. Typical tube shapes and flow fields are presented. In strongly collapsed tubes, at finite values of the Reynolds number, two ’jets‘ develop downstream of the region of strongest collapse and persist for considerable axial distances. For sufficiently high values of the Reynolds number, these jets impact upon the sidewalls and spread azimuthally. The consequent azimuthal transport of momentum dramatically changes the axial velocity profiles, which become approximately uTheta-shaped when the flow enters the rigid downstream pipe. Further convection of momentum causes the development of a ring-shaped velocity profile before the ultimate return to a parabolic profile far downstream.

System and Method for Traversing Pipes

Science.gov (United States)

Graf, Jodi (Inventor); Pettinger, Ross (Inventor); Azimi, Shaun (Inventor); Magruder, Darby (Inventor); Ridley, Justin (Inventor); Lapp, Anthony (Inventor)

2017-01-01

A system and method is provided for traversing inside one or more pipes. In an embodiment, a fluid is injected into the one or more pipes thereby promoting a fluid flow. An inspection device is deployed into the one or more pipes at least partially filled with a flowing fluid. The inspection device comprises a housing wherein the housing is designed to exploit the hydrokinetic effects associated with a fluid flow in one or more pipes as well as maneuver past a variety of pipe configurations. The inspection device may contain one or more sensors capable of performing a variety of inspection tasks.

Fatigue crack growth rate studies on pipes and pipe welds made of austenitic stainless steel and carbon steel

International Nuclear Information System (INIS)

Arora, Punit; Singh, P.K.; Bhasin, Vivek; Vaze, K.K.; Pukazhendhi, D.M.; Gandhi, P.; Raghava, G.

2011-01-01

The objective of the present study is to understand the fatigue crack growth behavior in austenitic stainless steel and carbon steel pipes and pipe welds by carrying out analysis/predictions and experiments. The Paris law has been used for the prediction of fatigue crack growth life. To carry out the analysis, Paris constants have been determined for pipe (base) and pipe weld materials by using Compact Tension (CT)/Three Point Bend (TPB) specimens machined from the actual pipe/pipe weld. Analyses have been carried out to predict the fatigue crack growth life of pipes/pipe welds having part through cracks on the outer surface. In the analyses, Stress Intensity Factors (K) have been evaluated through two different schemes. The first scheme considers the 'K' evaluations at two points of the crack front i.e. maximum crack depth and crack tip at the outer surface. The second scheme accounts for the area averaged root mean square stress intensity factor (K RMS ) at deepest and surface points. In order to validate the analytical procedure/results, experiments have been carried out on full scale pipe and pipe welds with part through circumferential crack. Fatigue crack growth life evaluated using both schemes have been compared with experimental results. Use of stress intensity factor (K RMS ) evaluated using second scheme gives better fatigue crack growth life prediction compared to that of first scheme. (author)

Underclad crack development of steam generators tube sheets and reactor vessels nozzles in PWR plants

International Nuclear Information System (INIS)

Faure, F.; Bocquet, P.; Boudot, R.; Zacharie, G.

1985-01-01

Defects formed, before stress relieving treatment, under the coating of tube plates of steam generators and vessel pipes are cold cracks formed in the segregation zone during surface coating without pre- and postheating of the 2nd layers and eventually of the following coating layers. To solve this problem, the conditions of pre- and post-heating are reinforced and applied to all the coating layers. 13 refs [fr

Operative behaviour of a condenser tube under ETA chemistry

International Nuclear Information System (INIS)

Chocron, Mauricio; Burkart, Arturo; Rodriguez, Ivanna; Raul, Manera; Diego, Quinteros

2012-09-01

Among the various recommendations for the surveillance of the integrity of the materials of the Secondary Cycle (Balance of Plant) it is the periodic removal of a steam generator tube and a condenser tube and their analysis. It considers assessment of the water chemistry, corrosion and the reciprocal effect on or from other components of the cycle. Embalse N.P.P. is a CANDU 6 type, Pressurized Heavy Water Reactor, located in Cordoba Province, Argentina. Previous papers have shown results on tubes removed from the steam generators (Bordoni et al., NPC'08, September 15-18, 2008, Berlin, Germany; 6 th Canadian Nuclear Society - Steam Generators Conference, November 8-11, 2009, Toronto, Canada). Considering that the Embalse BOP has mixed metallurgy, i.e., steam generator tubes made of A800, piping made of ferrous alloys and condenser tubes made of Admiralty Brass and also taking into account that the chemistry has been modified from Morpholine control to ETA control (Fernandez et. al, NPC'2010, October 3-7, Quebec City, Canada), it has been decided to remove and analyze a condenser tube that has been placed in operation coincidently with the establishment of the ETA chemical control. The extraction is dated along with the November 2011 Plant Programmed Outage. Objectives are assessing the operative behavior of the tube performing visual and optical microscope inspection, SEM analysis of the oxides and deposits in exposed surfaces and occluded locations like tube sheet and other tests as well. Results are compared to the same analysis performed on a new tube in storage and integrated with the chemical operative figures of the cycle during the period: chemical data and corrosion products transport. (authors)

Flow induced vibrations of secondary piping of L.M.F.B.R

International Nuclear Information System (INIS)

Gibert, R.J.; Axisa, F.

1977-01-01

A method for evaluating the characteristics of vibrations caused by internal flow in three-dimensional piping systems conveying high density fluids, is presented. The excitation of the circuit is mainly caused by the flow singularities, and it is shown that the problem may be reduced to calculate the response of the circuit to an acoustical pressure discontinuity, localized at each flow singularity. The theoretical formulation of the coupled acoustical-mechanical problem and its numerical solution by the french computer code TEDEL, are given. An experimental test of the method is described. The tested piping system consists of a stainless steel tube circuit comprising four 90 0 bends, conveying water. Vibrations are excited by a half closed gate valve. Satisfactory results are obtained concerning both the frequencies of resonance of the circuit and the level of the vibrations observed

A study on the impediment of thickness diminution of Carbon steel tube by using a applied magnetic field

International Nuclear Information System (INIS)

Kim, Jong Oh; Kim, Jong Hui; Cho, Wan Sik; Hong, Sung Min; Park, Yun Won

2001-03-01

Magnetic properties of the carbon steel tube which is used as the pipe laying of cooling water in nuclear power plant were measured to research the impediment of thickness diminution of carbon steel tube. Magnetic field distribution of carbon steel tube in the applied magnetic field was simulated by computer program. On the basis of the simulation results, Alnico 5DG and Alnico 5 were selected as the permanent magnets applicable to the carbon steel tube. Sm2Co17 magnet was used to compare the performance of permanent magnets. The experimental apparatus similar to the draining environment of cooling water in nuclear power plant was also manufactured in order to research the impediment of thickness diminution of carbon steel carbon tube

Radiation buildup and control in BWR recirculation piping

International Nuclear Information System (INIS)

Meyer, W.; Wood, R.M.; Rao, T.V.; Vook, R.W.

1987-01-01

Boiling water nuclear reactors (BWRs) employ stainless steel (Types 304 or 316 NG) pipes in which high-purity water at temperatures of ∼ 275 0 C are circulated. Various components of the system, such as valves and bearings, often contain hard facing metal alloys such as Stellite-6. These components, along with the stainless steel tubing and feedwater, serve as sources of 59 Co. This cobalt, along with other soluble and insoluble impurities, is carried along with the circulating water to the reactor core where it is converted to radioactive 60 Co. After reentering the circulating water, the 60 Co can be incorporated into a complex corrosion layer in the form of CoCr 2 O 4 and/or CoFe 2 O 4 . The presence of even small amounts of 60 Co on the walls of BWR cooling systems is the dominant contributor to inplant radiation levels. Thus BWR owners and their agents are expending significant time and resources in efforts to reduce both the rate and amount of 60 Co buildup. The object of this research is twofold: (a) to form a thin diffusion barrier against the outward migration of cobalt from a cobalt-containing surface and (b) to prevent the growth of a 60 Co-containing corrosion film. The latter goal was the more important since most of the radioactive cobalt will originate from sources other than the stainless steel piping itself

Current results for the NRC's short cracks in piping and piping welds research program

International Nuclear Information System (INIS)

Wilkowski, G.; Krishnaswamy, P. Brust, F.; Francini, R.; Ghadiali, N.; Kilinski, T.; Marschall, C.; Rahman, S.; Rosenfield, A.; Scott, P.

1994-01-01

The overall objective of the Short Cracks in Piping and Piping Welds Program is to verify and improve engineering analyses to predict the fracture behavior of circumferentially cracked pipe under quasi-static loading with particular attention to crack lengths typically used in LBB or flaw evaluation criteria. The program consists of 8 technical tasks as listed below. Task 1 Short through-wall-cracked (TWC) pipe evaluations. Task 2 Short surface-cracked pipe evaluations. Task 3 Bi-metallic weld crack evaluations. Task 4 Dynamic strain aging and crack instabilities. Task 5 Fracture evaluations of anisotropic pipe. Task 6 Crack-opening-area evaluations. Task 7 NRCPIPE Code improvements. Task 8 Additional efforts. Since the last WRSM meeting several additional tasks have been initiated in this program. These are discussed in Task 8. Based on results to date, the first seven tasks have also been modified as deemed necessary. The most significant accomplishments in each of these tasks since the last WRSIM meeting are discussed below. The details of all the results presented here are published in the semiannual reports from this program

Pulsating Heat pipe Only for Space (PHOS): results of the REXUS 18 sounding rocket campaign

International Nuclear Information System (INIS)

Creatini, F; Guidi, G M; Belfi, F; Cicero, G; Fioriti, D; Di Prizio, D; Piacquadio, S; Becatti, G; Orlandini, G; Frigerio, A; Fontanesi, S; Nannipieri, P; Rognini, M; Morganti, N; Filippeschi, S; Di Marco, P; Fanucci, L; Baronti, F; Mameli, M; Manzoni, M

2015-01-01

Two Closed Loop Pulsating Heat Pipes (CLPHPs) are tested on board REXUS 18 sounding rocket in order to obtain data over a relatively long microgravity period (approximately 90 s). The CLPHPs are partially filled with FC-72 and have, respectively, an inner tube diameter larger (3 mm) and slightly smaller (1.6 mm) than the critical diameter evaluated in static Earth gravity conditions. On ground, the small diameter CLPHP effectively works as a Pulsating Heat Pipe (PHP): the characteristic slug and plug flow pattern forms inside the tube and the heat exchange is triggered by thermally driven self-sustained oscillations of the working fluid. On the other hand, the large diameter CLPHP works as a two- phase thermosyphon in vertical position and doesn't work in horizontal position: in this particular condition, the working fluid stratifies within the device as the surface tension force is no longer able to balance buoyancy. Then, the idea to test the CLPHPs in reduced gravity conditions: as the gravity reduces the buoyancy forces becomes less intense and it is possible to recreate the typical PHP flow pattern also for larger inner tube diameters. This allows to increase the heat transfer rate and, consequently, to decrease the overall thermal resistance. Even though it was not possible to experience low gravity conditions due to a failure in the yoyo de-spin system, the thermal response to the peculiar acceleration field (hyper-gravity) experienced on board are thoroughly described. (paper)

An assessment of composite repair system in offshore platform for corroded circumferential welds in super duplex steel pipe

Directory of Open Access Journals (Sweden)

Silvio de Barros

2018-04-01

Full Text Available The main aim of this study is to assess the effectiveness of a composite repair system in severely corroded circumferential welds in super duplex stainless steel pipes as a preventive measure against the premature corrosion damage at the welds. Artificial defects were fabricated on the super duplex steel tube in order to reproduce the localized corrosion damage defects found in real welded joints. Three kinds of through thickness defects were considered: 25%, 50% and 96% of the perimeter of the pipe. The performance of the repaired pipe was assessed by hydrostatic tests as per ISO 24817 standard. The results showed that the composite repair system can sustain the designed failure pressure even for the pipe damaged with through-wall defect up to 96% of the perimeter of the pipe. Hence, the composite repair system can be used as a preliminary tool to protect the unexpected or premature failure at the welds and maintain an adequate level of mechanical strength for a given operating pressure. This composite repair system can assure that the pipe will not leak until a planned maintenance of the line. Nevertheless, further work is still desirable to improve the confidence in the long-term performance of bonded composite

Mechanical reliability analysis of tubes intended for hydrocarbons

Energy Technology Data Exchange (ETDEWEB)

Nahal, Mourad; Khelif, Rabia [Badji Mokhtar University, Annaba (Algeria)

2013-02-15

Reliability analysis constitutes an essential phase in any study concerning reliability. Many industrialists evaluate and improve the reliability of their products during the development cycle - from design to startup (design, manufacture, and exploitation) - to develop their knowledge on cost/reliability ratio and to control sources of failure. In this study, we obtain results for hardness, tensile, and hydrostatic tests carried out on steel tubes for transporting hydrocarbons followed by statistical analysis. Results obtained allow us to conduct a reliability study based on resistance request. Thus, index of reliability is calculated and the importance of the variables related to the tube is presented. Reliability-based assessment of residual stress effects is applied to underground pipelines under a roadway, with and without active corrosion. Residual stress has been found to greatly increase probability of failure, especially in the early stages of pipe lifetime.

Numerical Investigation for Strengthening Heat Transfer Mechanism of the Tube-Row Heat Exchanger in a Compact Thermoelectric Generator

Science.gov (United States)

Zhang, Zheng; Chen, Zijian; Liu, Hongwu; Yue, Hao; Chen, Dongbo; Qin, Delei

2018-06-01

According to the basic principle of heat transfer enhancement, a 1-kW compact thermoelectric generator (TEG) is proposed that is suitable for use at high temperatures and high flow speeds. The associated heat exchanger has a tube-row structure with a guide-plate to control the thermal current. The heat exchanger has a volume of 7 L, and the TEG has a mass of 8 kg (excluding the thermoelectric modules (TEMs)). In this paper, the heat transfer process of the tube-row exchanger is modeled and analyzed numerically; and the influences of its structure on the heat transfer and temperature status of the TEMs are investigated. The results show that use of the thin - wall pipes and increase of surface roughness inside the pipes are effective ways to improve the heat transfer efficiency, obtain the rated surface temperature, and make the TEG compact and lightweight. Furthermore, under the same conditions, the calculated results are compared with the data of a fin heat exchanger. The comparison results show that the volume and mass of the tube-row heat exchanger are 19% and 33% lower than those of the fin type unit, and that the pressure drop is reduced by 16%. In addition, the average temperature in the tube-row heat exchanger is increased by 15°C and the average temperature difference is increased by 19°C; the tube-row TEG has a more compact volume and better temperature characteristics.

Numerical Investigation for Strengthening Heat Transfer Mechanism of the Tube-Row Heat Exchanger in a Compact Thermoelectric Generator

Science.gov (United States)

Zhang, Zheng; Chen, Zijian; Liu, Hongwu; Yue, Hao; Chen, Dongbo; Qin, Delei

2018-04-01

According to the basic principle of heat transfer enhancement, a 1-kW compact thermoelectric generator (TEG) is proposed that is suitable for use at high temperatures and high flow speeds. The associated heat exchanger has a tube-row structure with a guide-plate to control the thermal current. The heat exchanger has a volume of 7 L, and the TEG has a mass of 8 kg (excluding the thermoelectric modules (TEMs)). In this paper, the heat transfer process of the tube-row exchanger is modeled and analyzed numerically; and the influences of its structure on the heat transfer and temperature status of the TEMs are investigated. The results show that use of the thin - wall pipes and increase of surface roughness inside the pipes are effective ways to improve the heat transfer efficiency, obtain the rated surface temperature, and make the TEG compact and lightweight. Furthermore, under the same conditions, the calculated results are compared with the data of a fin heat exchanger. The comparison results show that the volume and mass of the tube-row heat exchanger are 19% and 33% lower than those of the fin type unit, and that the pressure drop is reduced by 16%. In addition, the average temperature in the tube-row heat exchanger is increased by 15°C and the average temperature difference is increased by 19°C; the tube-row TEG has a more compact volume and better temperature characteristics.

Spiral multiple-effect diffusion solar still coupled with vacuum-tube collector and heat pipe

KAUST Repository

Huang, Bin-Juine; Chong, Tze-Ling; Wu, Po-Hsien; Dai, Han-Yi; Kao, Yeong-Chuan

2015-01-01

© 2015 Elsevier B.V. A novel solar still with spiral-shape multiple-effect diffusion unit is developed in the present study. The test results of a 14-effect unit coupled with vacuum-tube solar collector (absorber area 1.08m2) show that the highest

Drill pipe bridge plug

International Nuclear Information System (INIS)

Winslow, D.W.; Brisco, D.P.

1991-01-01

This patent describes a method of stopping flow of fluid up through a pipe bore of a pipe string in a well. It comprises: lowering a bridge plug apparatus on a work string into the pipe string to a position where the pipe bore is to be closed; communicating the pipe bore below a packer of the bridge plug apparatus through the bridge plug apparatus with a low pressure zone above the packer to permit the fluid to flow up through the bridge plug apparatus; engaging the bridge plug apparatus with an internal upset of the pipe string; while the fluid is flowing up through the bridge plug apparatus, pulling upward on the work string and the bridge plug apparatus and thereby sealing the packer against the pipe bore; isolating the pipe bore below the packer from the low pressure zone above the packer and thereby stopping flow of the fluid up through the pipe bore; disconnecting the work string from the bridge plug apparatus; and maintaining the bridge plug apparatus in engagement with the internal upset and sealed against the pipe bore due to an upward pressure differential applied to the bridge plug apparatus by the fluid contained therebelow

Pipe supports and anchors - LMFBR applications

International Nuclear Information System (INIS)

Anderson, M.J.

1983-06-01

Pipe design and support design can not be treated as separate disciplines. A coordinated design approach is required if LMFBR pipe system adequacy is to be achieved at a reasonable cost. It is particularly important that system designers understand and consider those factors which influence support train flexibility and thus the pipe system dynamic stress levels. The system approach must not stop with the design phase but should continue thru the erection and acceptance test procedures. The factors that should be considered in the design of LMFBR pipe supports and anchors are described. The various pipe support train elements are described together with guidance on analysis, design and application aspects. Post erection acceptance and verification test procedures are then discussed

A Built for Purpose Micro-Hole Coiled Tubing Rig (MCTR)

Energy Technology Data Exchange (ETDEWEB)

Bart Patton

2007-09-30

This report will serve as the final report on the work performed from the contract period October 2005 thru April 2007. The project 'A Built for Purpose Microhole Coiled Tubing Rig (MCTR)' purpose was to upgrade an existing state-of-the-art Coiled Tubing Drilling Rig to a Microhole Coiled Tubing Rig (MCTR) capable of meeting the specifications and tasks of the Department of Energy. The individual tasks outlined to meet the Department of Energy's specifications are: (1) Concept and development of lubricator and tool deployment system; (2) Concept and development of process control and data acquisition; (3) Concept and development of safety and efficiency improvements; and (4) Final unit integration and testing. The end result of the MCTR upgrade has produced a unit capable of meeting the following requirements: (1) Capable of handling 1-inch through 2-3/8-inch coiled tubing (Currently dressed for 2-3/8-inch coiled tubing and capable of running up to 3-1/2-inch coiled tubing); (2) Capable of drilling and casing surface, intermediate, production and liner hole intervals; (3) Capable of drilling with coiled tubing and has all controls and installation piping for a top drive; (4) Rig is capable of running 7-5/8-inch range 2 casing; and (5) Capable of drilling 5,000 ft true vertical depth (TVD) and 6,000 ft true measured depth (TMD).

Numerical analysis of magnetic field effects on hydro-thermal behavior of a magnetic nanofluid in a double pipe heat exchanger

Energy Technology Data Exchange (ETDEWEB)

Shakiba, Ali, E-mail: Shakiba7858@yahoo.com [Department of Mechanical Engineering, Mazandaran Institute of Technology, Babol (Iran, Islamic Republic of); Vahedi, Khodadad, E-mail: Khvahedi@ihu.ac.ir [Department of Mechanical Engineering, Imam Hossein University, Tehran (Iran, Islamic Republic of)

2016-03-15

This study attempts to numerically investigate the hydro-thermal characteristics of a ferrofluid (water and 4 vol% Fe{sub 3}O{sub 4}) in a counter-current horizontal double pipe heat exchanger, which is exposed to a non-uniform transverse magnetic field with different intensities. The magnetic field is generated by an electric current going through a wire located parallel to the inner tube and between two pipes. The single phase model and the control volume technique have been used to study the flow. The effects of magnetic field have been added to momentum equation by applying C++ codes in Ansys Fluent 14. The results show that applying this kind of magnetic field causes kelvin force to be produced perpendicular to the ferrofluid flow, changing axial velocity profile and creating a pair of vortices which leads to an increase in Nusselt number, friction factor and pressure drop. Comparing the enhancement percentage of Nusselt number, friction factor and pressure drop demonstrates that the optimum value of magnetic number for Re{sub ff}=50 is between Mn=1.33×10{sup 6} and Mn=2.37×10{sup 6}. So applying non-uniform transverse magnetic field can control the flow of ferrofluid and improve heat transfer process of double pipe heat exchanger. - Highlights: • Effect of applying non-uniform transverse magnetic field on a ferrofluid for enhancing the cooling process in a double pipe heat exchanger is investigated. • Heat exchanger is exposed to a non-uniform transverse magnetic field with different intensities. • The magnetic field is generated by an electric current going through a wire located parallel to inner tube and between two pipes. • Applying this field produces kelvin force to change axial velocity profile and creating a pair of vortices increasing Nusselt number, friction factor and pressure drop.

Insulated pipe clamp design

International Nuclear Information System (INIS)

Anderson, M.J.; Hyde, L.L.; Wagner, S.E.; Severud, L.K.

1980-01-01

Thin wall large diameter piping for breeder reactor plants can be subjected to significant thermal shocks during reactor scrams and other upset events. On the Fast Flux Test Facility, the addition of thick clamps directly on the piping was undesired because the differential metal temperatures between the pipe wall and the clamp could have significantly reduced the pipe thermal fatigue life cycle capabilities. Accordingly, an insulated pipe clamp design concept was developed. 5 refs

Experimental investigation of pulsating heat pipe performance with regard to fuel cell cooling application

International Nuclear Information System (INIS)

Clement, Jason; Wang Xia

2013-01-01

A pulsating heat pipe (PHP) is a closed loop, passive heat transfer device. Its operation depends on the phase change of a working fluid within the loop. Design and performance testing of a pulsating heat pipe was conducted under conditions to simulate heat dissipation requirements of a proton exchange membrane (PEM) fuel cell stack. Integration of pulsating heat pipes within bipolar plates of the stack would eliminate the need for ancillary cooling equipment, thus also reducing parasitic losses and increasing energy output. The PHP under investigation, having dimensions of 46.80 cm long and 14.70 cm wide, was constructed from 0.3175 cm copper tube. Heat pipes effectiveness was found to be dependent upon several factors such as energy input, types of working fluid and its filling ratio. Power inputs to the evaporator side of the pulsating heat pipe varied from 80 to 180 W. Working fluids tested included acetone, methanol, and deionized water. Filling ratios between 30 and 70 percent of the total working volume were also examined. Methanol outperformed other fluids tested; with a 45 percent fluid fill ratio and a 120 W power input, the apparatus took the shortest time to reach steady state and had one of the smallest steady state temperature differences. The various conditions studied were chosen to assess the heat pipe's potential as cooling media for PEM fuel cells. - Highlights: ► Methanol as a working fluid outperformed both acetone and water in a pulsating heat pipe. ► Performance for the PHP peaked with methanol and a fill ratio of 45 percent fluid to total volume. ► A smaller resistance was associated with a higher power input to the system.

Riser pipe elevator

Energy Technology Data Exchange (ETDEWEB)

Bennett, W.; Jimenez, A.F.

1987-09-08

This patent describes a method for storing and retrieving a riser pipe, comprising the steps of: providing an upright annular magazine comprised of an inside annular wall and an outside annular wall, the magazine having an open top; storing the riser pipe in a substantially vertically oriented position within the annular magazine; and moving the riser pipe upwardly through the open top of the annular magazine at an angle to the vertical along at least a portion of the length of the riser pipe.

PHASE CHANGE AROUND A FINNED TUBE

Directory of Open Access Journals (Sweden)

Aytunç EREK

2003-01-01

Full Text Available This study presents the heat transfer enhancement in the thermal energy storage system by using radially finned tube. The solution of the system consists of the solving the equations of the heat transfer fluid (HTF, the pipe wall and fin, and the phase change material (PCM as one domain. The control volume finite difference approach and the semi implicit solver (SIS are used to solve the equations. Fully developed velocity distribution is taken in the HTF. Flow parameters (Re number and inlet temperature of coolant and fin parameters (the number of fins, fin length, fin thickness are found to influence solidification fronts and the total stored energy.

Miniature Heat Pipes

Science.gov (United States)

1997-01-01

Small Business Innovation Research contracts from Goddard Space Flight Center to Thermacore Inc. have fostered the company work on devices tagged "heat pipes" for space application. To control the extreme temperature ranges in space, heat pipes are important to spacecraft. The problem was to maintain an 8-watt central processing unit (CPU) at less than 90 C in a notebook computer using no power, with very little space available and without using forced convection. Thermacore's answer was in the design of a powder metal wick that transfers CPU heat from a tightly confined spot to an area near available air flow. The heat pipe technology permits a notebook computer to be operated in any position without loss of performance. Miniature heat pipe technology has successfully been applied, such as in Pentium Processor notebook computers. The company expects its heat pipes to accommodate desktop computers as well. Cellular phones, camcorders, and other hand-held electronics are forsible applications for heat pipes.

Development of an ISI robot for the fast breeder reactor MONJU primary heat transfer system piping

International Nuclear Information System (INIS)

Tagawa, Akihiro; Ueda, Masashi; Yamashita, Takuya; Narisawa, Masataka; Haga, Kouichi

2011-01-01

This paper describes the development of a new inspection robot for the In-Service Inspection of the heat transfer system of the Fast Breeder Reactor MONJU. The inspection was carried out using a tire-type ultrasonic sensor for volumetric tests at high temperature (atmosphere, 55degC; piping surface, 80degC) and radiation exposure condition (dose rate, 10 mGy/h; piping surface dose rate, 15 mGy/h). An inspection robot using a new tire type for the ultrasonic testing sensor and a new control method was developed. A signal-to-noise ratio S/N over 2 was obtained during the functional test for a calibration defect with a depth of 50%t (from the tube wall thickness). In the automatic inspection test, an EDM slit with a depth of 9% from the pipe thickness was detectable and with an S/N ratio = 4.0 (12.0 dB). (author)

Reliability and durability of the 12Kh1MF steel tubes of electroslag remelting and their welded joints

International Nuclear Information System (INIS)

Lanskaya, K.A.; Kulikova, L.V.; Mazel', R.E.; Khromchenko, F.A.; Strizhenova, V.F.

1978-01-01

Results of investigating the positive effect of electrolag remelting (ESR) on the properties of the base metal and welded joint of the 12Kh1MF steel steam pipes with the aim of increasing their durability up to 20,000 hrs, are presented. To estimate the quality and properties of tube billet metal, microstructure, content and nature of nonmetallic inclusions, content of gases, austenite grain size, austenite transformations during continuous cooling, metal ductility, mechanical properties at different temperatures and heat resisting properties, have been investigated. It is established, that the base metal in tubes of electroslag remelting possess higher heat resistance, while welded joints besides, have high deformability and resistance to brittle fracture

Piping research program plan

International Nuclear Information System (INIS)

1988-09-01

This document presents the piping research program plan for the Structural and Seismic Engineering Branch and the Materials Engineering Branch of the Division of Engineering, Office of Nuclear Regulatory Research. The plan describes the research to be performed in the areas of piping design criteria, environmentally assisted cracking, pipe fracture, and leak detection and leak rate estimation. The piping research program addresses the regulatory issues regarding piping design and piping integrity facing the NRC today and in the foreseeable future. The plan discusses the regulatory issues and needs for the research, the objectives, key aspects, and schedule for each research project, or group of projects focussing of a specific topic, and, finally, the integration of the research areas into the regulatory process is described. The plan presents a snap-shot of the piping research program as it exists today. However, the program plan will change as the regulatory issues and needs change. Consequently, this document will be revised on a bi-annual basis to reflect the changes in the piping research program. (author)

Implementation status of performance demonstration program for steam generator tubing analysts in Korea

International Nuclear Information System (INIS)

Cho, Chan Hee; Lee, Hee Jong; Yoo, Hyun Ju; Nam, Min Woo; Hong, Sung Yull

2013-01-01

Some essential components in nuclear power plants are periodically inspected using non destructive examinations, for example ultrasonic, eddy current and radiographic examinations, in order to determine their integrity. These components include nuclear power plant items such as vessels, containments, piping systems, pumps, valves, tubes and core support structure. Steam generator tubes have an important safety role because they constitute one of the primary barriers between the radioactive and non radioactive sides of the nuclear power plant. There is potential that if a tube bursts while a plant is operating, radioactivity from the primary coolant system could escape directly to the atmosphere. Therefore, in service inspections are critical in maintaining steam generator tube integrity. In general, the eddy current testing is widely used for the inspection of steam generator tubes due tube integrity. In general, the eddy current testing is widely used for the inspection of steam generator tubes due to its high inspection speed and flaw detectability on non magnetic tubes. However, it is not easy to analyze correctly eddy current signals because they are influenced by many factors. Therefore, the performance of eddy current data analysts for steam generator tubing should be demonstrated comprehensively. In Korea, the performance of steam generator tubing analysts has been demonstrated using the Qualified Data Analyst program. This paper describes the performance demonstration program for steam generator tubing analysts and its implementation results in Korea. The pass rate of domestic analysts for this program was 71.4%

Implementation status of performance demonstration program for steam generator tubing analysts in Korea

Energy Technology Data Exchange (ETDEWEB)

Cho, Chan Hee; Lee, Hee Jong; Yoo, Hyun Ju; Nam, Min Woo [KHNP Central Research Institute, Daejeon (Korea, Republic of); Hong, Sung Yull [Yeungnam Univ., Gyeongsan (Korea, Republic of)

2013-02-15

Some essential components in nuclear power plants are periodically inspected using non destructive examinations, for example ultrasonic, eddy current and radiographic examinations, in order to determine their integrity. These components include nuclear power plant items such as vessels, containments, piping systems, pumps, valves, tubes and core support structure. Steam generator tubes have an important safety role because they constitute one of the primary barriers between the radioactive and non radioactive sides of the nuclear power plant. There is potential that if a tube bursts while a plant is operating, radioactivity from the primary coolant system could escape directly to the atmosphere. Therefore, in service inspections are critical in maintaining steam generator tube integrity. In general, the eddy current testing is widely used for the inspection of steam generator tubes due tube integrity. In general, the eddy current testing is widely used for the inspection of steam generator tubes due to its high inspection speed and flaw detectability on non magnetic tubes. However, it is not easy to analyze correctly eddy current signals because they are influenced by many factors. Therefore, the performance of eddy current data analysts for steam generator tubing should be demonstrated comprehensively. In Korea, the performance of steam generator tubing analysts has been demonstrated using the Qualified Data Analyst program. This paper describes the performance demonstration program for steam generator tubing analysts and its implementation results in Korea. The pass rate of domestic analysts for this program was 71.4%.

Development of LBB Piping Evaluation Diagram for APR 1000 Main Steam Line Piping

International Nuclear Information System (INIS)

Yang, J. S.; Jeong, I. L.; Park, C. Y.; Bai, S. Y.

2010-01-01

This paper presents the piping evaluation diagram (PED) to assess the applicability of Leak-Before- Break(LBB) for APR 1000 main steam line piping. LBB-PED of APR 1000 main steam line piping is independent of its piping geometry and has a function of the loads applied in piping system. Also, in order to evaluate LBB applicability during construction process with only the comparative evaluation of material properties between actually used and expected, the expected changes of material properties are considered in the LBB-PED. The LBB-PED, therefore, can be used for quick LBB evaluation of APR 1000 main steam line piping of both design and construction

Pipe rupture test results: 4-inch pipe whip tests under PWR LOCA conditions

International Nuclear Information System (INIS)

Miyazaki, Noriyuki; Ueda, Shuzo; Isozaki, Toshikuni; Kato, Rokuro; Kurihara, Ryoichi; Yano, Toshikazu; Miyazono, Shohachiro

1982-09-01

This report summarizes the results of 4-inch pipe whip tests (RUN No. 5506, 5507, 5508 and 5604) under the PWR LOCA conditions. The dynamic behaviors of the test pipe and restraints were studied in the tests. In the tests, the gap between the test pipe and the restraints was kept at the constant value of 8.85 mm and the overhang length was varied from 250 mm to 650 mm. The dynamic behaviors of the test pipe and the restraint were made clear by the outputs of strain gages and the measurements of residual deformations. The data of water hammer in subcooled water were also obtained by the pressure transducers mounted on the test pipe. The main conclusions obtained from the tests are as follows. (1) The whipping of pipe can be prevented more effectively as the overhang length becomes shorter. (2) The load acting on the restraint-support structure becomes larger as the overhang length becomes shorter. (3) The restraint farther from the break location does not limit the pipe movement except for the first impact when the overhang length is long. (4) The ultimate moment M sub(u) of the pipe at the restraint location can be used to predict the plastic collapse of the whipping pipe. (5) The restraints slide along the pipe axis and are subjected to bending moment, when the overhang length is long. (author)

Remote controlled in-pipe manipulators for dye-penetrant inspection and grinding of weld roots inside of pipes

International Nuclear Information System (INIS)

Seeberger, E.K.

2000-01-01

Technical plants which have to satisfy stringent safety criteria must be continuously kept in line with the state of art. This applies in particular to nuclear power plants. The quality of piping in nuclear power plants has been improved quite considerably in recent years. By virtue of the very high quality requirements fulfilled in the manufacture of medium-carrying and pressure-retaining piping, one of the focal aspects of in-service inspections is the medium wetted inside of the piping. A remote controlled pipe crawler has been developed to allow to perform dye penetrant testing of weld roots inside piping (ID ≥ 150 mm). The light crawler has been designed such that it can be inserted into the piping via valves (gate valves, check valves,...) with their internals removed. Once in the piping, all crawler movements are remotely controlled (horizontal and vertical pipes incl. the elbows). If indications are found these discontinuities are ground according to a qualified procedure using a special grinding head attached to the crawler with complete extraction of all grinding residues. The in-pipe grinding is a special qualified three (3) step performance that ensures no residual tensile stress (less than 50 N/mm 2 ) in the finish machined austenitic material surface. The in-pipe inspection system, qualified according to both the specifications of the German Nuclear Safety Standards Commission (KTA) and the American Society of Mechanical Engineers (ASME), has already been used successfully in nuclear power plants on many occasions. (author)

Large-bore pipe decontamination

International Nuclear Information System (INIS)

Ebadian, M.A.

1998-01-01

The decontamination and decommissioning (D and D) of 1200 buildings within the US Department of Energy-Office of Environmental Management (DOE-EM) Complex will require the disposition of miles of pipe. The disposition of large-bore pipe, in particular, presents difficulties in the area of decontamination and characterization. The pipe is potentially contaminated internally as well as externally. This situation requires a system capable of decontaminating and characterizing both the inside and outside of the pipe. Current decontamination and characterization systems are not designed for application to this geometry, making the direct disposal of piping systems necessary in many cases. The pipe often creates voids in the disposal cell, which requires the pipe to be cut in half or filled with a grout material. These methods are labor intensive and costly to perform on large volumes of pipe. Direct disposal does not take advantage of recycling, which could provide monetary dividends. To facilitate the decontamination and characterization of large-bore piping and thereby reduce the volume of piping required for disposal, a detailed analysis will be conducted to document the pipe remediation problem set; determine potential technologies to solve this remediation problem set; design and laboratory test potential decontamination and characterization technologies; fabricate a prototype system; provide a cost-benefit analysis of the proposed system; and transfer the technology to industry. This report summarizes the activities performed during fiscal year 1997 and describes the planned activities for fiscal year 1998. Accomplishments for FY97 include the development of the applicable and relevant and appropriate regulations, the screening of decontamination and characterization technologies, and the selection and initial design of the decontamination system

Characterization of radioactive contamination inside pipes with the Pipe Explorer trademark system

International Nuclear Information System (INIS)

Kendrick, D.T.; Cremer, C.D.; Lowry, W.; Cramer, E.

1995-01-01

The U.S. Department of Energy's nuclear facility decommissioning program needs to characterize radiological contamination inside piping systems before the pipe can be recycled, remediated, or disposed. Science and Engineering associates, Inc. under contract with the DOE Morgantown Energy Technology Center has developed and demonstrated the Pipe Explorer trademark system, which uses an inverting membrane to transport various characterization sensors into pipes. The basic process involves inverting (turning inside out) a tubular impermeable membrane under air pressure. A characterization sensor is towed down the interior of the pipe by the membrane. Advantages of this approach include the capability of deploying through constrictions in the pipe, around 90 degrees bends, vertically up and down, and in slippery conditions. Because the detector is transported inside the membrane (which is inexpensive and disposable), it is protected from contamination, which eliminates cross-contamination. Characterization sensors that have been demonstrated with the system thus far include: gamma detectors, beta detectors, video cameras, and pipe locators. Alpha measurement capability is currently under development. A remotely operable Pipe Explorer trademark system has been developed and demonstrated for use in DOE facilities in the decommissioning stage. The system is capable of deployment in pipes as small as 2-inch-diameter and up to 250 feet long. This paper describes the technology and presents measurement results of a field demonstration conducted with the Pipe Explorer trademark system at a DOE site. These measurements identify surface activity levels of U-238 contamination as a function of location in drain lines. Cost savings to the DOE of approximately $1.5 million dollars were realized from this one demonstration