Hobson M12 Galvanised Spring Washer - Each

The spring washer was the first washer that offered a solution to the loosening of bolted assemblies. These are hardened washers that are split with out of plane deformations. They should be used under the head of the bolt with the assembly being tensioned by rotating the nut. If they need to be used on the nut side, another hardened flat round washer should be used between the nut and the split washer. When the washers are flattened, a prescribed tension is achieved in the assembly. When the threaded fasteners are tightened, the protruding corner edges of the split-lock spring washers bite into both the compressing surfaces in a manner that resists anti-clockwise rotation to vibration in a manner similar to a ratchet.