Fracture Analysis and Improvement Research on 42CrMo Steel Pull Rod of DMS Soluble Ball Seat

Based on the fracture problem of pull rod in the process of joint operation of soluble tee segmentation and cluster perforation, through fracture macro-analysis, force analysis, chemical composition analysis, hardness test, metallographic structure analysis and tensile property test, analyzed comprehensively reasons for fracture of pull rod. The results showed that the main causes of fracture of pull rod were the two factors: tensile strength of pull rod was insufficient; the performance of material organization was poor.Proposed three improvement measures for anti-fracture design of pull rod: the tempering hardness should be increased;the heat treatment process should be improved; the design of pull rod should be optimized.