Nylon Insert Lock Nut

A nylon insert lock nut is a hex nut with a nylon ring at the top. The ring grips the thread to resist loosening from vibration.

A nylon insert lock nut holds a bolt or screw against vibration. The nylon insert grips the thread and resists loosening. It takes a bolt or screw of the same thread and often a washer.

Hot-dip galvanising gives a thick coating for outdoor and wet areas. Zinc plating gives a thin, bright coating for indoor use. A plain finish has no coating and can rust unless protected.

This kind of lock nut is often made in steel, stainless steel 304, stainless steel 316 or brass. Stainless steel 304 suits general outdoor use, while 316 gives better resistance to salt and chemicals. Brass is used where corrosion resistance and non-magnetic properties matter.

This is a general guide to checking this kind of part. It says nothing about any supplier's parts.

Ask for a mill test certificate or a certificate of conformance for the material and grade. On receipt, check the nylon insert is seated and undamaged, and that the nut runs onto a matching bolt with the expected resistance. Confirm the thread form and hex dimensions.