Låsmuttern

Låsmuttern, often translated as locknut or locking nut, is a type of nut designed to resist loosening under vibration and torque. This resistance is crucial in applications where fasteners are subjected to dynamic loads or movements, which can cause standard nuts to gradually back off. Various designs exist to achieve this locking function.

One common type is the prevailing torque nut, which uses deformation to create friction. Examples include the nylon insert locknut, where a plastic ring deforms the threads of the bolt as it's screwed in, or distorted thread locknuts, where the nut's threads are intentionally misaligned to create a tight fit against the bolt's threads. Another category is the non-prevailing torque nut, which relies on a separate component or a specific feature of the nut itself to prevent loosening after it has been tightened. Examples include castle nuts and slotted nuts, which require a cotter pin or wire to be inserted through a hole in the bolt or shaft to physically prevent rotation. Serrated flange locknuts have teeth on their underside that bite into the mating surface once tightened, creating a mechanical lock. The choice of locknut depends on factors such as the severity of vibration, the required clamping force, and whether the nut needs to be reusable.