The degree of influence of pushing temperature, speed

The degree of influence of pushing temperature, speed and friction coefficient on elbow formation  

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 in the pipeline system bending, is related to the safe 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 the hot pushing made form process of elbow has carried on the simulation of the system, and put forward the best forming process parameters according to the simulation results, 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:  

(1) using involute forming period of the central axis of mutation as a core rod hole enlargement, its main design thought is infinite radius of curvature, curvature radius decreases to the plastic section that is conducive to the flow of metal in the process of hole enlargement, causes the elbow arc metal materials can fully to outer arc, so as to avoid the hot pushing elbow bend the elbow lateral tensile machine deformation thinning, compression of the medial thickening  Uneven wall thickness ensures the roundness of outer diameter and uniformity of wall thickness.  

(2) The control variable method is adopted to optimize the design of the central axis, and the optimal design is selected for simulation.  

(3) The bending forming process under different process parameters was simulated by using finite element simulation software Abaqus and orthogonal test method.  The simulation results show that too high pushing temperature will lead to wrinkling and too low pushing temperature will lead to cracking