SIMULATION-AIDED INVESTIGATION OF THE EFFECT OF A PRE FORMING PROCESS ON THE INITIATION OF CRACKS, THE REQUIRED FORGING FORCES AND MATERIAL FLOWLINES FOR MINING GROUND SUPPORT CLAMPS' MANUFACTURE USING THE HOT-FORGING TECHNIQUE

摘要

In this study, the influence of the number of forging stages on the crack formation and forging forces in the hot-forging process for mining support clamps that were produced from 31Mn4 material was investigated. In this context, a single-stage process has been considered and a multiple-stage forging process that included a pre-forming stage was fictionalized with the aim of preventing crack formation by obtaining crack-formation zones. It is aimed to improve the toughness properties of the final product by ensuring that the material flow lines are obtained in accordance with the product geometry as well as preventing the formation of cracks by the forging process design, including the preforming step of the mining support clamp. Designed dies and workpieces were simulated using the finite-volume method. According to the simulation results of forging process, the stress and strain variation of materials is obtained as max. 229 MPa and 3.969 MPa. Damage analysis of the sample with effective stress and strain is exposed as 0.438-1.0 flash surface of material. The increase in the forming step decreased the forging forces per step and the crack formation was prevented and the material flowlines can be arranged in accordance with the product geometry in the presence of the preforming stage in the hot-forging process and that this regulation has a reducing effect on the forging forces. The material flowlines of the samples obtained from real production were examined and validation of the simulations and actual production was provided.