Self Locking nuts contain some arrangement that provides resistance to becoming loose during service conditions. 

Some of the types are given below.

Nyloc Nut

A nyloc nut, also referred to as a nylon-insert lock nut, polymer-insert lock nut, or elastic stop nut, is a kind of locknut with a nylon collar insert that resists turning.

Nylon lock nuts differ from a standard hex nut in that they have a nylon insert secured within the nut. The nylon insert is located in a tapered section located at the back of the nut.

When you install the nylon lock nut onto a bolt or threaded stud, the nylon insert wraps around the threads and locks the nut in place.

This gives a nylon lock nut a distinct advantage over a lock washer when the bolt or threaded stud is subject to vibration, as the nylon lock nut is unaffected by vibration.

The plastic insert is placed at the end of the nut, with an inner diameter (ID) slightly smaller than the major diameter of the screw. The insert deforms elastically over the threads of the screw, without having threads in turn cut into it.

The nylon insert locks the nut by friction against the screw under the applied radial compressive force. Nyloc nuts retain their locking ability up to 250 °F (121 °C).

Installation:

Always fix a Nylock Nut with the metal thread going on first.

Inspect the nylon insert of the lock nut to ensure that it is intact after installation.

Caution – A nylock nut should only be used once and the nylon insert no longer performs its function to 100% of design .. therefore nylock nuts should be discarded and replaced after each use.

A variety of locking nuts available in ready stock with us.

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Flanged Nylock Nuts

These nuts are created to a standard of DIN 6926.
Flange Nyloc (nylon insert) Nuts are torque prevailing nuts which use plastic/nylon inserts that are located towards the top of the nut – which reduce its inner diameter – therefore deforming the insert over the mating thread and capturing the bolt or screw and providing a locking feature.

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Metal Lock Nuts

All Metal lock nuts work on the principle of a slight deformation in the nut. Locking is achieved by deformation of the last thread. This is a top locking style nut.
Our metal lock nuts are similar to DIN 980

Metal Lock Nut SS-304 A2 B4C58 – Download Datasheet
Metal Lock Nut SS-316 A4 B6C58 – Download Datasheet

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Nylock Dome Nuts

Nylock Dome nuts (also known as Self Locking Acorn Nuts) are made to a standard of DIN 986.

Nyloc (nylon insert) Dome Nuts are dome nuts which use plastic/nylon inserts that are located towards the top of the nut – which reduce its inner diameter – therefore deforming the insert over the mating thread and capturing the bolt or screw and providing a locking feature which resists vibrations.

The dome or cap provides a seal, which protects against entry of moisture giving longer life to the assembly. The dome shape is also aesthetically pleasing.