In order to solve the problems of excess ovality and cross-section distortion of longitudinally submerged arc welding pipes after forming,a new three-roller continuous setting round process was proposed.This process c...In order to solve the problems of excess ovality and cross-section distortion of longitudinally submerged arc welding pipes after forming,a new three-roller continuous setting round process was proposed.This process can be divided into three stages:loading stage,roll bending stage and unloading stage.Based on the discretization idea,the mechanical model of the primary statically indeterminate problem of the longitudinally submerged arc welding pipes at the roll bending stage was established,and the deformation response was obtained.The simulation and theoretical results show that there are three positive bending regions and three reverse bending regions along the circumference of the pipe.The loading force of each roller shows growth,stability and downward trend with time.The error between the theoretical fitting curve and the simulated data point is very small,and the simulation results verify the reliability of the theoretical calculation.The experimental results show that the residual ovality decreases with the increase of the reduction,and the reduction of the turning point is the optimum reduction.In addition,the residual ovality of the pipe is less than 0.7%without cross-section distortion,which verifies the feasibility of this process.展开更多
In this article the research and development of X70 large diameter longitudinal seam submerged arc welded (LSAW) steel pipes for West East Gas Transportation Pipeline project (WEGTP) in China are introduced, including...In this article the research and development of X70 large diameter longitudinal seam submerged arc welded (LSAW) steel pipes for West East Gas Transportation Pipeline project (WEGTP) in China are introduced, including the key technique, fabrication of pipe production line, mass production and the latest progress of LSAW steel pipe technique.展开更多
基金supported by the National Natural Science Foundation of China (Nos. 52005431, 51705449 and 51975509)the Natural Science Foundation of Hebei Province of China (No. E2020203086)the National Major Science and Technology Projects of China (No. 2018ZX04007002)
文摘In order to solve the problems of excess ovality and cross-section distortion of longitudinally submerged arc welding pipes after forming,a new three-roller continuous setting round process was proposed.This process can be divided into three stages:loading stage,roll bending stage and unloading stage.Based on the discretization idea,the mechanical model of the primary statically indeterminate problem of the longitudinally submerged arc welding pipes at the roll bending stage was established,and the deformation response was obtained.The simulation and theoretical results show that there are three positive bending regions and three reverse bending regions along the circumference of the pipe.The loading force of each roller shows growth,stability and downward trend with time.The error between the theoretical fitting curve and the simulated data point is very small,and the simulation results verify the reliability of the theoretical calculation.The experimental results show that the residual ovality decreases with the increase of the reduction,and the reduction of the turning point is the optimum reduction.In addition,the residual ovality of the pipe is less than 0.7%without cross-section distortion,which verifies the feasibility of this process.
文摘In this article the research and development of X70 large diameter longitudinal seam submerged arc welded (LSAW) steel pipes for West East Gas Transportation Pipeline project (WEGTP) in China are introduced, including the key technique, fabrication of pipe production line, mass production and the latest progress of LSAW steel pipe technique.
