Abstract: A bolt with a partially threaded shank has a plurality of locking grooves located on the shank between the thread and its head. The bolt is inserted through a component stack and spacing washers and a stepped reaction washer such that at least half of the locking grooves are left exposed. A deformable frusto-conical locking ring is positioned on a nut having a circular receiving cavity on one end. The nut and locking ring are positioned on the thread of the bolt and tightened so that the locking ring is deformed from a frusto-conical shape to a substantially flat disc such that its bore diameter is reduced, thereby retaining it within one of the locking grooves. The outer diameter of the receiving cavity abuts the stepped reaction washer.

Abstract: A bolt (10) with a partially threaded shank has a plurality of locking grooves located on the shank between the thread and its head (11). The bolt (10) is inserted through a component stack and spacing washers and a stepped reaction washer such that at least half of the locking grooves (13) are left exposed. A deformable frusto-conical locking ring (17) is positioned on a nut (15) having a circular receiving cavity on one end. The nut (15) and locking ring (17) are positioned on the thread (14) of the bolt (10) and tightened so that the locking ring (17) is deformed from a frusto-conical shape to a substantially flat disc such that its bore diameter is reduced, thereby retaining it within one of the locking grooves (13). The outer diameter of the receiving cavity (16) abuts the stepped reaction washer (18).