Nylon Insert Nuts

Trojan Special Fasteners Ltd routinely manufactures nylon insert nuts to customer's requirements in multiple material and finish combinations. Nylon insert nuts are typically hexagon nuts with a polyamide (usually Nylon 66) insert.

The non-metallic ring is placed on one of the nut and as it's inner diameter is slightly smaller than the major diameter of the screw, it elastically deforms over the threads of the screw. This means that the non-metallic ring applies a compressive force against the screw which means that the nut doesn't loosen with vibration and also cushions against vibration as well.

These kind of nuts are also known as aircraft lock nuts, elastic lock nuts, elastic stop nuts, nyloc nuts, nylock nuts and nylon insert stop nuts. These are reusable (up to a limited number of time) because the nylon insert will return to its original shape. Nylon insert nuts are a form of prevailing torque nut because they have a mechanism that creates frictional interference between threads of mating components. This also means that application has to be with a wrench or spanner because the nylon ring creates increased torque.

In addition to standard preferred sizes, we also manufacture non preferred and non standard or special thread and nut forms and sizes.

Typical nuts can be used up until 120 degrees Celsius, but certain materials are available (on request) which can be used in nuts for higher temperatures, although we would recommend an all-metal prevailing torque type nut for high temperature use.

There is some disagreement if nyloc/nylock/nylon insert nuts can or should be reused. Some polymer rings are not damaged upon installation, in which case the fastener is reused multiple times. However, this does not take into account any degradation of the polymer ring which comes about due to the stresses it's under upon application or even removal, how long the fastener has been in use, how many times it has been re-tightened or even what chemicals and pollutants it may have come into contact with. It is common for companies to reuse and retighten fasteners if the prevailing torque is within specified ranges.

However, in critical applications, Trojan always suggests replacement of the fastener. They are relatively inexpensive and easy to replace, so there should not be a reason for retightening or reapplication. Various specifications for aerospace-grade self-locking nuts require that the running torque be maintained after a number of cycles of assembly, but without preloading the fastener.

Tall Nylon Insert Nuts (P Type)

Short Nylon Insert Nuts (T type)

Nylon Insert Flange Nuts

We can manufacture to the following specifications:

In addition to machining nuts to your dimensions, sample or drawing, we can machine nylon insert nuts to the following specifications:

Standard Description
ASME/ANSI B18.16.3M Prevailing torque hexagon nylon insert nuts
ASME/ANSI B18.6.6 Prevailing torque hexagon nylon insert nuts
BS 4929-1 Prevailing torque hexagon nylon insert nuts, metric threads
BS 4929-2 Prevailing torque hexagon nylon insert nuts, unified threads
DIN 34814 Plastic/Nylon hexagon nuts
DIN 6924 Prevailing torque hexagon nylon insert nuts
DIN 6926 Prevailing torque hexagon nylon insert flange nuts
DIN 982 Prevailing torque hexagon thick nylon insert nuts
DIN 985 Prevailing torque hexagon thin nylon insert nuts
EN 1663 Prevailing torque hexagon nylon insert nuts
EN 1666 Prevailing torque hexagon nylon insert nuts
ISO 10511 Prevailing torque thin hexagon nylon insert nuts
ISO 10512 Prevailing torque hexagon nylon insert nuts, style 1
Standard Description
ISO 10513 Prevailing torque hexagon nylon insert nuts, style 2
ISO 12125 Prevailing torque hexagon nylon insert flange nuts
ISO 7040 Prevailing torque hexagon nylon insert nuts, style 1
ISO 7041 Prevailing torque hexagon nylon insert nuts, style 2
ISO 7043 Prevailing torque hexagon nylon insert flange nuts
NF E25-409 Prevailing torque hexagon nylon insert nuts, style 1
NF E25-412 Prevailing torque hexagon nylon insert nuts
NF E25-413 Prevailing torque hexagon nylon insert flange nuts
NF E25-506 Prevailing torque hexagon nylon insert flange nuts
UNI 2733 Prevailing torque thick hexagon nylon insert nuts
UNI 7473 Prevailing torque short hexagon nylon insert nuts
UNI 7474 Prevailing torque thick hexagon nylon insert nuts

Additionally, we can manufacture:

  • NU Series nylon insert lock nuts
  • NTU Series nylon insert lock nuts
  • NTE Series nylon insert lock nuts
  • NE Series nylon insert lock nuts