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Gayathri Vijayakumar - One of the best experts on this subject based on the ideXlab platform.
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Hot Bending of Large Size Seamless Primary Pipe for Sodium Cooled Fast Breeder Reactor
Structural Integrity Assessment, 2020Co-Authors: Gagan Gupta, S. Clement Ravi Chandar, P. Puhtiyavinayagam, Kumar Rathees Chinannan Ramasamy, Sriramachandra Aithal, Ramja Sritharan, Sangeetha Raghupathy, Sakthivel Ramasamy, Vijay Balasubramaniyan, Gayathri VijayakumarAbstract:In a pool-type fast Fast reactor neutron reactor, the primary Pipe supplies cold sodium from pump to grid plate. The primary Pipe of Prototype Fast Breeder Reactor (PFBR) was made from pressing the plates by die and punch and joining the two halves by welding in longitudinal direction. Though weld joints are extensively used and acceptable, it is desirable to reduce the number of weld joints, which increases the reliability of the component. In this context, it is proposed to use Seamless Pipe Seamless Pipe for primary Pipes of future FBRs. However, the large-sized Seamless bends needed for meeting this objective are not readily available and hence, a technology development exercise was taken-up to bend a large size Seamless austenitic stainless steel Pipe (Outer diameter 457 mm and nominal thickness 14.27 mm) to a bend radius of 2 times its diameter for a bend angle of 110°. The objective of the development was to demonstrate the manufacturing feasibility of Seamless Pipe Seamless Pipe bend, with controlled dimensions, before its adoption in the design. This paper discusses the details of development activities carried out in various stages towards bending of a large size Seamless Pipe. The hot bending attempts through die and punch Die and punch method involving large number of trials as well as through induction bending Induction bending technique are detailed out. After many unsuccessful trials of hot bending on carbon steel Pipe with various die and punch options (viz. end support die, full-length support die) and several challenges with induction bending Induction bending , primary Pipe bending has been successfully demonstrated, meeting the specification requirements. The paper also highlights various qualification tests, which the primary Pipe bend has met. The successful completion of hot bending of large diameter Seamless Pipe Seamless Pipe has demonstrated the indigenous manufacturing capability of such bends and has given confidence for its incorporation in the primary Pipes of future FBR.
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Hot Bending of Large Size Seamless Primary Pipe for Sodium Cooled Fast Breeder Reactor
Lecture Notes in Mechanical Engineering, 2019Co-Authors: Gagan D. Gupta, P. Puhtiyavinayagam, Kumar Rathees Chinannan Ramasamy, Sriramachandra Aithal, Ramja Sritharan, Sangeetha Raghupathy, Sakthivel Ramasamy, Vijay Balasubramaniyan, S. Clement Ravi Chandar, Gayathri VijayakumarAbstract:In a pool-type fast neutron reactor, the primary Pipe supplies cold sodium from pump to grid plate. The primary Pipe of Prototype Fast Breeder Reactor (PFBR) was made from pressing the plates by die and punch and joining the two halves by welding in longitudinal direction. Though weld joints are extensively used and acceptable, it is desirable to reduce the number of weld joints, which increases the reliability of the component. In this context, it is proposed to use Seamless Pipe for primary Pipes of future FBRs. However, the large-sized Seamless bends needed for meeting this objective are not readily available and hence, a technology development exercise was taken-up to bend a large size Seamless austenitic stainless steel Pipe (Outer diameter 457 mm and nominal thickness 14.27 mm) to a bend radius of 2 times its diameter for a bend angle of 110°. The objective of the development was to demonstrate the manufacturing feasibility of Seamless Pipe bend, with controlled dimensions, before its adoption in the design. This paper discusses the details of development activities carried out in various stages towards bending of a large size Seamless Pipe. The hot bending attempts through die and punch method involving large number of trials as well as through induction bending technique are detailed out. After many unsuccessful trials of hot bending on carbon steel Pipe with various die and punch options (viz. end support die, full-length support die) and several challenges with induction bending, primary Pipe bending has been successfully demonstrated, meeting the specification requirements. The paper also highlights various qualification tests, which the primary Pipe bend has met. The successful completion of hot bending of large diameter Seamless Pipe has demonstrated the indigenous manufacturing capability of such bends and has given confidence for its incorporation in the primary Pipes of future FBR.
Li Lian-jin - One of the best experts on this subject based on the ideXlab platform.
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Effect of size and temperature on residual stress of the Seamless Pipe in the sizing process
Heavy Machinery, 2006Co-Authors: Li Lian-jinAbstract:The sizing process must be taken in order to eliminate the size and roundness error after the Seamless Pipe rolled and heat treated.As the last procedure of producing the Seamless Pipe,the sizing process plays a key role in not only controlling the Pipe size and geometry shape,but also affecting its mechanical performance.Therefore,to meet the tolerance requirements,investigation has been carried out to find the relationship between residual stress and the sizing measure and temperature.A detailed analysis thus is performed to understand the sizing deformation process,and will help reduce the residual stress of sizing process,and achieve an optimized sizing technology and improve the mechanical performance.The analysis results obtained may provide a theoretical foundation for establishing the sizing process.
L I Lianjin - One of the best experts on this subject based on the ideXlab platform.
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effect of sizing measure and temperature on residual stress of the Seamless Pipe in the sizing process
Journal of Plasticity Engineering, 2007Co-Authors: L I LianjinAbstract:The sizing process must be taken in order to eliminate the size tolerance and roundness one after the Seamless Pipe rolled and heat treated.As the last procedure of producing the Seamless Pipe,the sizing process plays a key role in not only controlling the Pipe size and geometry shape,but also affecting its mechanical performance.Therefore,to meet the tolerance requirements,systematic investigation has been carried out to find the dependence relationship of distribution of residual stress on the sizing measure and temperature.A detailed analysis thus is performed to understand metal flow on the sizing deformation process.This analysis will aid to reduce the residual stress of sizing process,achieve an optimized sizing technology and enhance the mechanical performance.The analysis results obtained may provide a theoretical foundation for establishing the sizing process.
Rafael Colás - One of the best experts on this subject based on the ideXlab platform.
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Hot forging of fittings made from Seamless Pipe
Ironmaking & Steelmaking, 2004Co-Authors: C. Lázaro-naranjo, P. Fodor, M.p. Guerrero-mata, J. Martínez, Rafael ColásAbstract:AbstractThe hot forging of connecting fittings known as tees is analysed and described in the present paper. These parts are forged in a vertical press from preforms cut from Seamless Pipes in which a hole, which will be the third mouth, is cut with an acetylene torch. The process requires that the portion of the preform to be forged is hot enough to allow the flow of material, while the rest of the piece is able to resist the pressure without bending. The experimental work was conducted using instrumented preforms by the insertion of eight type K thermocouples at different portions of the body to record the thermal cycle; a grid was inscribed on the surface of the preforms to compute the various strain components. The pieces were heated and, before forging, were subjected to the standard procedure of immersing the portion opposite to the third mouth in water at room temperature. An attempt to forge one piece directly from heating, without immersion in water, was made, but this was a failure as the materi...
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Forming of Seamless Pipe fittings
Journal of Materials Processing Technology, 2002Co-Authors: A. Rodriguez, P. Fodor, Margarita Mezzetti, Rafael ColásAbstract:Abstract Analysis and results of the high temperature forming of Seamless Pipe fittings produced at a local factory are presented in this work. The studies were conducted by recording the thermal evolution in different parts of the piece as it was being forged, which was done by placing a series of type K thermocouples within the part and logging the data into a computer driven system. The initial trials put in evidence the need to change the heating practice in order to ensure a greater thermal homogeneity. Metallographic evaluation was carried out on formed pieces to study variations in their microstructure before and after the changes in the heating practice were made. Modification of this practice resulted in improvements in quality, such as the reduction in the variation in microstructure and wall thickness, as well as an increase in productivity, as the pressing speed was augmented.
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Strain distribution analysis of hot forged Seamless Pipe fittings
Materials Science and Technology, 2000Co-Authors: A. Rodriguez, G. Olvera, P. Fodor, Rafael ColásAbstract:AbstractA strain distribution analysis was carried out on hot forged Seamless Pipe fittings produced at a factory. The studies were conducted on Pipe preforms, cut from a Seamless Pipe, which had a grid inscribed on the outside surface. The dimensions of the individual cells were measured before processing of the preforms and, once the parts had cooled down to room temperature, the dimensions of the distorted grids were recorded. The different components of strain were evaluated from both sets of measurements. Thermal evolution during forging was recorded by inserting a series of type K thermocouples into the preforms and logging the data into a computer system. Two preforms were loaded together in a single trial, whereas a third one was deformed by itself to evaluate the consistency of the process. Results from the analysis compare favourably with measurements of the change in wall thickness obtained by ultrasonic means in one of the pieces.
Kazuo Yamazaki - One of the best experts on this subject based on the ideXlab platform.
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Control for Straightening Process of Seamless Pipe.
JSME international journal. Series 3 Vibration control engineering engineering for industry, 1991Co-Authors: Takaaki Katoh, Eizo Urata, Minoru Nakanishi, Kazuo YamazakiAbstract:Seamless Pipes have some terminal end bends which must be eliminated before shipment. This paper describes a real-time control system for a press straightening process. The straightening process must account for elastic springback, which is a strong function of the material properties of the Pipe. On-line measurements of reactive forces and deflection of the Pipe during the early part of the bending process are performed to form an elastic-plastic model in a microcomputer. The final correct die position to yield the desired unloaded shape is predicted using the elastic-plastic model. Through a series of experiments on different materials and different sizes and shapes, the resulting straightness of the Pipes was within 0.18 mm, which is sufficiently smaller than product allowance.
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Control for straightening process of Seamless Pipe.
Transactions of the Japan Society of Mechanical Engineers. C, 1990Co-Authors: Takaaki Katoh, Eizo Urata, Minoru Nakanishi, Kazuo YamazakiAbstract:Seamless Pipes have some terminal end bends which must be cured before shipment. This paper describes a real-time control system for a press straightening process. The straightening process must account for elastic springback, which is a strong function of the material properties of the Pipe. On-line measurements of reactive force and deflection of the Pipe during the early part of the bending process are performed to form an elastic-plastic model in a microcomputer. The final correct die position to yield the desired unloaded shape is predicted using the elastic-plastic model. Through a series of experiments on different materials and different sizes and shapes, the straightening process gave an accuracy of 0.18 mm/m, which is sufficiently smaller than product allowances.