In view of the common safety hazards such as braking slip and speed out of control of monorail crane locomotives widely used in auxiliary transportation of mines under complex working conditions such as wet slip and large dip angle, the technical bottlenecks are analyzed in detail. On this basis, the technical breakthroughs of the new monorail crane stall protection device in three dimensions of automatic monitoring, self-locking braking and buffering energy absorption are systematically expounded. Integrating the stall protection device as an independent module into the existing monorail crane system is an efficient and economical way to realize the safety upgrading and technical transformation of mine stock equipment, which is of great practical significance for improving the intrinsic safety level of mine auxiliary transportation.