A comparative analysis of a four-stage and five-stage cold forging of a hollow element

Abstract

Abstract The paper presents the results of a computer simulation of the process of cold forging of a hollow element with an outer flange. Computer testing was conducted in DEFORM 2D/3D using the calculation module 2D. A tube-shaped billet, made of 42CrMo4 grade steel and the inner diameter of Ø45mm, wall thickness 8 mm and length 193.5 mm was used. The analysed process was conducted in two variants. The first one was conducted in four stages, with the first two stages consisting of upsetting the flange part and the next two stages forging on cones. In the second variant, an additional stage of forging on cones was performed, aiming at elimination of the folding on the inner wall of the forging. An analysis of the technology was conducted on the basis of distributions of effective strain, values of the Cockcroft-Latham fracture criterion and progresses of the forming force. On the basis of the research conducted, it was claimed that the five-stage forging process is more favourable.