Abstract: In order to improve the product quality of 16MnDR steel low-temperature pressure vessels and prevent cold cracks during welding, this paper analyzes the selection principles of welding materials, the effects of welding heat input on welding quality, the effects of post-weld heat treatment on the elimination of residual stress and the control of welding process. Through the testing of different welding heat input energies in the process of welding process evaluation, a set of welding process parameters that can ensure the welding quality is selected. The results from non-destructive testing and physical and chemical performance tests show that the optimal welding process can ensure the welding quality of 16MnDR steel low-temperature pressure vessels. This can provide technical support for the manufacture of low-temperature pressure vessels.

Key words: 16MnDR, low-temperature pressure vessel, welding heat input, welding process, post-weld heat treatment