X-series combines Nord-Lock’s wedge-locking protection against spontaneous bolt loosening (due to vibration and dynamic loads) with an exclusive spring effect that protects against slackening due to settlement and relaxation. This combination makes X-series the first, true multifunctional solution, and offers the highest security for critical joints, without compromise.
Upon tightening the fastener, the washers flatten and the serrations engage the contact surfaces. Since the cam angle αis larger than the thread pitch β, the wedge-locking effect will prevent any rotation of the fastener. Directly after tightening, the joint settles and the fastener sinks into the surface material. The washers immediately deflect and the spring effect (Fs) counteracts the slackening movement of the bolt, thereby preventing loss of preload on the joint. These multiple functions continuously act on the bolted joint to maintain preload and prevent spontaneous bolt loosening, serving as an effective solution for vibration, dynamic loads, settlement and relaxation