STAINLESS STEEL SERRATED FLANGED NUTS

Serrated Flange Nuts – FAQs

What is a serrated flange nut?

A serrated flange nut is a hexagonal nut with an integral flanged base that incorporates serrations on the bearing surface. The flange acts like a built‑in washer, while the serrations grip the mating surface to help resist loosening caused by vibration.

How do serrated flange nuts work?

The integral flange distributes the load over a wider area, eliminating the need for a separate washer.
The serrations beneath the flange bite into the mating surface during tightening, creating resistance to rotation and helping to prevent the nut from loosening under vibration.

When are serrated flange nuts typically used?

Serrated flange nuts are commonly used:

  • In applications subject to vibration or movement
  • Where a washer is not desirable or practical
  • In mechanical, automotive, and general engineering assemblies
  • Where consistent clamping force is required over a wider surface area

They provide a quick and effective locking solution without additional components.

Are serrated flange nuts suitable as a primary fastening nut?

Yes. Serrated flange nuts are suitable for use as primary fastening nuts, provided they are correctly selected for the application. The nut body carries the mechanical load, while the flange and serrations provide resistance to loosening.

Can serrated flange nuts be reused?

Serrated flange nuts may be reused, but repeated use can reduce the effectiveness of the serrations. If the serrated surface becomes worn or damaged, the nut should be replaced to ensure reliable locking performance.

Do serrated flange nuts damage the mating surface?

The serrations are designed to grip the mating surface and may mark softer materials. For applications where surface damage must be avoided, a smooth flange nut or an alternative locking method should be considered.

What sizes and thread types do you supply?

We supply serrated flange nuts in:

  • Metric thread sizes
  • Inch thread sizes

Availability of sizes may vary depending on material.

What materials are available?

Our range of serrated flange nuts is available in:

  • Stainless steel A2
  • Stainless steel A4

These materials are supplied in both metric and inch thread forms. [pts-uk.com]

Are serrated flange nuts known by any other names?

Serrated flange nuts may also be referred to as:

  • Serrated flanged nuts
  • Flange lock nuts
  • Serrated washer‑face nuts

All describe the same nut design featuring an integral serrated flange.

How do I choose the correct serrated flange nut?

When selecting a serrated flange nut, consider:

  • Thread size and type (metric or inch) to match the mating fastener
  • Vibration levels in the application
  • Suitability of serrations for the mating surface material
  • Material selection (A2 or A4) based on corrosion resistance requirements