Numerical Simulation of Hot Extrusion Process for Dual-metal Clad Pipe

The-extrusion process of dual-metal clad pipe is numerically simulated with the DEFORM-3D finite element software.Also analyzed are the distribution and size of the stress and strain in the deformed body and their corresponding relationship with the extrusion temperature and the die temperature.Moreover the optimal extrusion is determined as 1 150~1 200℃.Pre-heating of the die before hot-extrusion is helpful for a smooth extrusion operation.Thanks to the hetero-temperature extrusion technique,the maximum equivalent stress difference in the deformed body is reduced,and the plastic flow difference between the inner layer and the outer layer of metal is reduced so as the extruded head and extruded end proportion is reduced,resulting in enhancement of the yield.Through the actual production verification,the calculated result of the simulated hot extrusion process are in good agreement with the measured result.