Patent attributes
Interchangeable reaction washer initially penetrates with outward bottom serration edges only during manual pre tightening. Slippage is thereby avoided at begin of the consecutive power torque wrench assisted full tightening of the nut and/or bolt head resting on it. As the load ramps up, the reaction washer flattens out and the bottom serrations gradually penetrate radially inwards. Reaction and actuation sockets of varying sizes matching a broad range of reaction washers and nut and/or bolt heads may be interchangeably snapped on a reaction coupling connected to the torque wrench housing. A clearance undercut underneath the reaction washer torque receiving flanges absorbs eventual debris to further assist unimpeded and fast coupling of the system. Radially oriented contact faces between reaction washer and reaction socket provide a snug contact unaffected by their toroidal movement during washer flattening and a force transfer free of radial force components.