Preload Fastener Assemblies
Countersunk (EN14399-7)

Product Code EN14399-7 HR

Sometimes abbreviated to HSFG bolts. Bolts which are of high tensile strength used in conjunction with high strength nuts and hardened steel washers in structural steelwork. The bolts are tightened to a specified minimum shank tension so that transverse loads are transferred across the joint by friction between the plates rather than by shear across the bolt shank. Friction Grip Bolting provides a simple method of transmitting loads through a structural joint, by the friction on the contact face, developed through the high clamping force from correctly tightened high strength bolts.

HSFG are fitted in clearance holes and since the connection is designed to resist slip, they are not subject to bearing or shear forces and therefore remain in virtual static tension throughout their life.