Self Locking Nuts

What are self locking nuts?

Self locking nuts, also known as prevailing torque nuts or stiff nuts, are fasteners designed to maintain a secure threaded connection under vibration or movement. Unlike standard nuts, they incorporate a locking feature that creates friction between the nut and bolt threads, helping prevent the joint from loosening during operation.

How do self locking nuts work?

Self locking nuts maintain clamping force by introducing resistance into the thread engagement. This resistance is typically created by a nylon insert or a controlled deformation of the nut’s threads. When the nut is tightened onto a bolt, the locking feature increases friction, helping prevent loosening caused by vibration or dynamic loads.

Are self locking nuts reusable?

Most self locking nuts can be reused a limited number of times. However, the prevailing torque created by the locking feature may reduce with repeated installation and removal. When the locking resistance declines below the required level, the nut should be replaced to maintain joint security.

What types of self locking nuts are available?

We supply a wide range of locking nut designs, including:

• Nylon insert lock nuts (Nyloc nuts)
• All-metal prevailing torque nuts
• Flanged locking nuts
• Thin pattern locking nuts
• Turret and specialist locking nuts

Different designs are suited to specific applications, including high vibration environments or high temperature conditions.

What materials are self locking nuts available in?

Self locking nuts are commonly manufactured from materials selected for strength and corrosion resistance. Typical options include:

• Stainless steel
• Carbon steel with protective finishes
• Aluminium
• Titanium

Material selection depends on the operating environment, load requirements, and corrosion exposure.

How do I choose the correct lock nut?

Selecting the appropriate locking nut depends on several factors:

• Application requirements, including vibration, temperature, and environmental exposure.
• Material compatibility, ensuring the nut matches the bolt and operating conditions.
• Thread size and type: The nut must match the mating fastener to ensure proper engagement.
• Strength requirements: The nut must be capable of supporting the required load.

If you require assistance selecting the correct locking nut, don’t hesitate to contact our experts for help, advice and a competitive price on the ideal locking nut whatever your application.