The elbow is the pipe system that bends the main p

The elbow is the pipe system that bends the main pipe fitting  

In recent years, with the development of shipbuilding and petrochemical, gas and other industries, as a liquid, gas pipeline elbow has been widely used.  When the pipe is bent, the bearing pressure of the inside and outside of the pipe wall is different due to the different mechanical properties of the inside and outside of the pipe wall.  Elbow, as one of the main connectors of the pipeline system bending, is related to the smooth operation of the whole system, so the structural design of elbow is very important.  To improve the manufacturing level and productivity of elbow forming is the main content to accelerate the key technological transformation of pipe fitting manufacturers.  By using the ABAQUS finite element simulation software of numerical simulation, and combining the test method of heat of elbow push into processes of system simulation, according to the results of simulation of forming process parameters, and analyzes the process parameters (such as push system temperature, push speed, friction coefficient) of the influence of bend forming process.  

The main research contents and results are as follows  

Involute of variation as the forming mandrel hole enlargement section of central axis, its main design thought is infinite radius of curvature decreases to the correct section of the radius of curvature, which facilitates the flow of metal in the process of expanding, the elbow inner arc metal material to flow to the outer arc fully, so as to avoid the hot pushing elbow bend the elbow lateral tensile machine deformation thinning, compression of the medial thickening of the wall thickness  Uniformity ensures the roundness of outer diameter and uniformity of wall thickness.  

The control variable method is used to optimize the design of the central axis, and the excellent design is selected for simulation.  

The bending process under different technological parameters was simulated by finite element simulation software combined with orthogonal test method.  The simulation results show that too high pushing temperature will lead to wrinkling and too low p