Abstract: Targeting urban rail transit vehicle bogie brake shoe pin revoked tread braking unit shaft loose phenomenon, based on the characteristics of brake shoe pin revoked shaft connection structure, bolt tightening torque is checked with calculation and bolt quality inspection control is investigated. The brake shoe revoked shaft installation process rules and enforcement is examined, which further concluded that pin screw hole residual rust-preventative oil decreases the intensity of locking glue, which is the root cause of the loose fault of brake shoe pin revocation shaft. The correctness of the inference is verified by the relevant simulation experiments. In view of the fault cause, the optimization measures such as using high strength thread locking glue, adding double self-locking gasket and increasing tightening torque are put forward. The results of relevant tests and applications show that the optimized measures can effectively avoid the occurrence of similar faults.