DIN 9250 VS Safety Lock Washers

DIN 9250 VS Safety Lock Washers are heavy-duty conical serrated washers developed for bolted joints requiring higher preload capacity than standard safety washer designs. Their defining feature is the increased washer thickness, which allows the conical section to withstand greater compressive loading while retaining its spring action under higher bolt pretension.

The VS type is commonly identified in the fastener market as a VS safety washer, VS serrated safety washer, heavy-duty ribbed lock washer, or Schnorr-type VS safety washer. It retains the characteristic serrations on both bearing faces, but its heavier cross-section distinguishes it from the standard S type. The inside diameter, outside diameter, and serration geometry remain the same as the corresponding S type, while the greater thickness is intended for higher pretension loads.

The VS design is particularly relevant to high-strength bolted joints using property classes 8.8 and 10.9. Compared with the standard S type, its increased thickness gives the washer greater load capacity when the joint requires higher preload. It is also used where the bearing conditions are more demanding, including elongated holes and hardened contact surfaces. The original SCHNORR specification lists VS washers for screw sizes M5 to M30.

Typical applications include machinery, industrial equipment, automotive assemblies, mechanical structures, and other bolted connections exposed to vibration, fluctuating loads, or high tightening forces. When selecting a VS safety washer, the bolt diameter and strength class, required preload, hole configuration, and hardness of the mating surfaces are important considerations.