At a certain wind power client's site, complex operational conditions posed challenges with conventional hydraulic torque wrenches' reaction arms, which exhibited poor adaptability. Not only did this lead to frequent interference during construction work, but insufficient operating clearance also created significant safety risks of hand entrapment. To completely eliminate this hazard and align with actual site conditions, a custom-designed reaction arm was developed. This ensures safe operation of the hydraulic torque wrench without safety concerns.