Abstract: As a key component connecting the mounting device and the turnout, the bolts at the angle iron of the mounting device are prone to fracture during daily operation. Aiming at this problem, this paper conducts a study, summarizes the causes of bolt fracture through on-site investigation and theoretical analysis, and puts forward targeted treatment measures. The research results can provide a scientific basis for the maintenance of turnout equipment and effectively reduce the potential safety hazards and operation costs caused by bolt fracture.