Research On Once Forming Of Thin-wall Head

As the main pressure-containing part of pressure vessel,head is widely used in aviation,aerospace,railway,chemical and nuclear power,and other fields,with high processing technology requirements,manufacturing process difficulty,complex processes and a long production cycle.In order to improve the economy and promote the further development of the industry,it’s necessary to achieve higher requirements on the performance of pressure vessels and pressure-containing parts,such as the ability to meet harsh conditions on strength,toughness,impact resistance,low temperature performance,anti corrosion and radiation properties.At the same time,advanced manufacturing process is required to satisfy the pressure vessel size tending to large-scale,long life,more convenient inspection and maintenance and other demands.Because of its simple processes,low production costs,cold deep drawing technology has become a focus of the present study.The forming process of the large thin-wall head is the key problem in the research of the stamping process.The main content of the research is how to avoid the forming defects such as wrinkling,bulging and cracking.Based on the theory of metal plastic forming,the forming process of the head is studied.As for the actual cold deep drawing forming defects of large thin-walled dished head,this paper presents a new kind of drawbeads design which is based on some study about the forming process of the conventional step-by-step deep drawing and the one-step forming process with drawbeads.The effects of stamping parameters,die design and friction coefficient on the forming defects are also analyzed.By using a finite element software Dynaform,the specific parameters of drawbeads design are determined.According with the finite element simulation and orthogonal tests,the combination of stamping technology parameters are optimized,The feasibility of the new scheme is verified by experiments,and the forming defects in the actual production are solved.providing an optimizational deep drawing process for head.