---
title: "What Are Wedge-Lock Washer Pairs Used For?"
description: "Wedge-Lock Washer Pairs (Trade series (cam wedge-lock pair)) are used for joints under vibration or dynamic load, locked by a cam angle greater than the thre…"
url: https://engineeringhardware.com/applications/wedge-lock-washer-pairs/
source: Engineering Hardware & Fasteners
---

# What Are Wedge-Lock Washer Pairs Used For?

Washers · Trade series (cam wedge-lock pair) · Application guide

Typical applications, the industries that specify wedge-lock washer pairs, and how to choose the right size, material and finish for the joint.

Wedge-Lock Washer Pairs are used for joints under vibration or dynamic load, locked by a cam angle greater than the thread lead rather than by friction. They are manufactured to Trade series (cam wedge-lock pair), and selection is driven by the nominal bolt size, the fit and tolerance the assembly requires, and the service environment.

- **Primary duty:** Joints under vibration or dynamic load, locked by a cam angle greater than the thread lead rather than by friction
- **Governing standard:** Trade series (cam wedge-lock pair)
- **Nominal bolt size range:** M6 to M20
- **Category:** Washers

Application notes are general engineering guidance. Verify the property class and any approval requirement against your own design calculation.

![What Are Wedge-Lock Washer Pairs Used For? application image](https://engineeringhardware.com/wp-content/uploads/2026/09/Wedge-Lock-Washers.webp)

The primary duty of Wedge-Lock Washer Pairs is joints under vibration or dynamic load, locked by a cam angle greater than the thread lead rather than by friction. Below: the sectors that specify them in volume, the checklist used to select the right size and material for the application, installation notes, and the known limits of the type. Stocked across roughly M6 to M20, they cover general to heavy-duty work.

## Typical Applications for Wedge-Lock Washer Pairs

The most common settings where these are specified:

- **Vibration applications:** spring and serrated types that maintain tension under cyclic load.
- **Timber & soft materials:** large-OD types that prevent pull-through.
- **General machine building:** fastening covers, brackets, motors and sub-assemblies on production equipment.
- **Maintenance & repair (MRO):** a stocked size for servicing existing plant where the original fastener spec must be matched.
- **Fabrication & metalwork:** bench and on-site assembly of steel frames, enclosures and weldments.

Product catalog

## Related Wedge-Lock Washers products

[![Lock Preventing Double Fold Self Wedge Lock Washer Nl6 S6oc Carbon Steel Stainless Steel and Steelplain DIN Light Industry](https://img.engineeringhardware.com/Lock-Preventing-Double-Fold-Self-Wedge-Lock-Washer-Nl6-S6oc-Carbon-Steel-Stainless-Steel-and-Steelplain-DIN-Light-Industry.webp)](https://engineeringhardware.com/product/lock-preventing-double-fold-self-wedge-lock-washer-nl6-s6oc-carbon-steel-stainless/)

Wedge-Lock & Anti-Vibration Washers

### [Lock Preventing Double Fold Self Wedge Lock Washer Nl6 S6oc Carbon Steel Stainless Steel and Steelplain DIN Light Industry](https://engineeringhardware.com/product/lock-preventing-double-fold-self-wedge-lock-washer-nl6-s6oc-carbon-steel-stainless/)

Lock Preventing Washers · DIN

**US$0.24**MOQ 100 pieces

[![DIN 25201 Double Fold Self-Locking Wedge Locking Washers for Mechanical Applications in High Vibration and High Temperature](https://img.engineeringhardware.com/DIN-25201-Double-Fold-Self-Locking-Wedge-Locking-Washers-for-Mechanical-Applications-in-High-Vibration-and-High-Temperature.webp)](https://engineeringhardware.com/product/din-25201-double-fold-self-locking-wedge-locking-washers-for-mechanical-applications/)

Wedge-Lock & Anti-Vibration Washers

### [DIN 25201 Double Fold Self-Locking Wedge Locking Washers for Mechanical Applications in High Vibration and High Temperature](https://engineeringhardware.com/product/din-25201-double-fold-self-locking-wedge-locking-washers-for-mechanical-applications/)

Flat Gasket · Stainless Steel

**US$0.0011 – 1.20**MOQ 1,000 pieces

[![SS304 316 DIN 25201 Double Fold Self Locking Washers Safety Knurling Wedge Lock Washers](https://img.engineeringhardware.com/SS304-316-DIN-25201-Double-Fold-Self-Locking-Washers-Safety-Knurling-Wedge-Lock-Washers.webp)](https://engineeringhardware.com/product/ss304-316-din-25201-double-fold-self-locking-washers-safety-knurling-wedge-lock-2/)

Wedge-Lock & Anti-Vibration Washers

### [SS304 316 DIN 25201 Double Fold Self Locking Washers Safety Knurling Wedge Lock Washers](https://engineeringhardware.com/product/ss304-316-din-25201-double-fold-self-locking-washers-safety-knurling-wedge-lock-2/)

Lock Washer · Stainless Steel

**US$0.012 – 0.036**MOQ 1,000 pieces

[![Zinc Plated DIN6797A External Tooth Lock Washer for Anti-Vibration Fastening](https://img.engineeringhardware.com/Zinc-Plated-DIN6797A-External-Tooth-Lock-Washer-for-Anti-Vibration-Fastening.webp)](https://engineeringhardware.com/product/zinc-plated-din6797a-external-tooth-lock-washer-for-anti-vibration-fastening/)

Wedge-Lock & Anti-Vibration Washers

### [Zinc Plated DIN6797A External Tooth Lock Washer for Anti-Vibration Fastening](https://engineeringhardware.com/product/zinc-plated-din6797a-external-tooth-lock-washer-for-anti-vibration-fastening/)

Lock Washer · Stainless Steel

**US$0.0252 – 0.12**MOQ 5,000 pieces

[![DIN25201 Wedge Lock Washer for Railway and Rail Transit Applications](https://img.engineeringhardware.com/DIN25201-Wedge-Lock-Washer-for-Railway-and-Rail-Transit-Applications.webp)](https://engineeringhardware.com/product/din25201-wedge-lock-washer-for-railway-and-rail-transit-applications/)

Wedge-Lock & Anti-Vibration Washers

### [DIN25201 Wedge Lock Washer for Railway and Rail Transit Applications](https://engineeringhardware.com/product/din25201-wedge-lock-washer-for-railway-and-rail-transit-applications/)

Lock Washer · Carbon Steel / Stainless Steel

**US$0.06 – 18.00**MOQ 1,000 sets

[![DIN25201 Stainless Steel Wedge Lock Washer](https://img.engineeringhardware.com/DIN25201-Stainless-Steel-Wedge-Lock-Washer.webp)](https://engineeringhardware.com/product/din25201-stainless-steel-wedge-lock-washer/)

Wedge-Lock & Anti-Vibration Washers

### [DIN25201 Stainless Steel Wedge Lock Washer](https://engineeringhardware.com/product/din25201-stainless-steel-wedge-lock-washer/)

Flat Gasket · Stainless Steel 304

**US$0.19**MOQ 1,000 pieces

[View all Wedge-Lock & Anti-Vibration Washers →](https://engineeringhardware.com/fastener-products/washers/wedge-lock-anti-vibration-washers/) [Full product catalog](https://engineeringhardware.com/products/)

## How to Specify Wedge-Lock Washer Pairs for Your Application

- **Size:** Match the nominal size to the mating thread or hole. This product spans M6–M20; check the full table below for the exact dimensions of each size.
- **Type & OD:** Select flat for load spreading, spring/serrated for anti-loosening, or fender/large-OD for soft or oversized holes.
- **Environment:** For damp, coastal or chemical exposure prefer A4/316 stainless or a suitable coating; indoors, plated steel or A2 is usually sufficient.
- **Standard:** This product is supplied to Trade series (cam wedge-lock pair). Quoting the standard on your order guarantees interchangeable dimensions between suppliers.

## Installation & Assembly Practice

- Place the washer under the rotating element (usually the nut) so tightening does not score the surface.
- Chamfered-hole side of a hardened washer faces the bolt head fillet.
- On serrated-flange hardware, do not add a plain washer — it defeats the serrations.

## Common Selection Mistakes with Wedge-Lock Washer Pairs

- Relying on a spring washer for locking on class 8.8+ joints — at high preload it flattens and adds nothing.
- Choosing an OD too small for soft material, so the head pulls through or embeds.

## Where Wedge-Lock Washer Pairs Are Not the Right Choice

A washer does not replace a locking feature on its own in severe vibration, and a spring washer adds little clamp on high-strength joints.

Custom manufacturing · Made to drawing

## Need a wedge-lock washer pairs outside the standard range?

Bore, outside diameter, thickness, temper and finish are the variables here — there is no thread to specify, so the fit and the bearing area are what the drawing has to pin down. Made by stamping or punching.

Minimum order from 2,000 pieces; samples within 7 days of drawing approval.

[Custom washer manufacturing](https://engineeringhardware.com/custom/washers/)[Send a drawing](https://engineeringhardware.com/custom/washers/#rfq)

## Technical Drawing

Dimensioned line drawing of M6 Wedge-Lock Washer Pairs to Trade series (cam wedge-lock pair). Side view and top view, drawn to the dimensions in the table below and redrawn for any size selected.

- **Inner diameter d1 (mm):** 6.4
- **Outer diameter d2 (mm):** 10.8
- **Thickness of pair t (mm):** 2.5
- **Cam angle:** approx. 12°
- **Fits property class up to:** 12.9
- **Material:** Hardened steel, Delta Protekt
- **Re-use:** Yes, teeth permitting

## Dimensions & Specifications (Trade series (cam wedge-lock pair))

| For bolt size | Inner diameter d1 (mm) | Outer diameter d2 (mm) | Thickness of pair t (mm) | Cam angle | Fits property class up to | Material | Re-use |
| --- | --- | --- | --- | --- | --- | --- | --- |
| M6 | 6.4 | 10.8 | 2.5 | approx. 12° | 12.9 | Hardened steel, Delta Protekt | Yes, teeth permitting |
| M8 | 8.7 | 13.5 | 3.4 | approx. 12° | 12.9 | Hardened steel, Delta Protekt | Yes, teeth permitting |
| M10 | 10.7 | 16.6 | 3.4 | approx. 12° | 12.9 | Hardened steel, Delta Protekt | Yes, teeth permitting |
| M12 | 13.0 | 19.5 | 4.0 | approx. 12° | 12.9 | Hardened steel, Delta Protekt | Yes, teeth permitting |
| M16 | 17.0 | 25.4 | 4.6 | approx. 12° | 12.9 | Hardened steel, Delta Protekt | Yes, teeth permitting |
| M20 | 21.4 | 30.7 | 5.2 | approx. 12° | 12.9 | Hardened steel, Delta Protekt | Yes, teeth permitting |

Inside the plant

## Manufactured in our own plant

This part is cold-formed, threaded, heat-treated and finished in-house. The stages below are where its class and finish are actually decided.

1. ![Wire rod feeding into a cold heading machine](https://engineeringhardware.com/wp-content/uploads/2026/08/09-wire-rod-feed-cold-heading-machine.webp) 01 **Cold heading** Wire rod is drawn to size and cold-formed into blanks. Forming rather than cutting keeps the grain flow continuous around the head, which is where a bolt is most likely to fail. Head dimensions and under-head radius checked at set-up and per shift.
2. ![Thread rolling machine producing bolt threads](https://engineeringhardware.com/wp-content/uploads/2026/08/03-thread-rolling-machine-bolt-production.webp) 02 **Thread rolling** Threads are rolled between hardened dies rather than cut. Rolled threads are stronger in fatigue than cut threads and hold pitch and flank angle far more consistently across a batch. Go / no-go ring gauges to ISO 965 tolerance class 6g.
3. ![Baskets of bolts staged for heat treatment](https://engineeringhardware.com/wp-content/uploads/2026/08/05-heat-treatment-baskets-black-bolts.webp) 03 **Heat treatment** Quench-and-temper brings carbon and alloy steel to the property class ordered — 8.8, 10.9 or 12.9 — with the furnace charge tracked so a finished lot can be traced back to it. Core hardness and tensile tested per lot to ISO 898-1.
4. ![Zinc plated bolts in a treatment basket](https://engineeringhardware.com/wp-content/uploads/2026/08/23-zinc-plated-bolts-treatment-basket.webp) 04 **Surface treatment** Zinc, zinc-nickel, hot-dip galvanizing, black oxide, phosphate and Dacromet, selected against the service environment rather than against the price list. Coating thickness and neutral salt spray hours to ISO 9227.

## Frequently Asked Questions

### What material should Wedge-Lock Washer Pairs be for outdoor use?

For damp, coastal or chemical environments specify A4 (316) stainless or a suitably coated steel. For indoor or dry use, A2 (304) stainless or zinc-plated steel is normally adequate.

### Are Wedge-Lock Washer Pairs made to a recognized standard?

Yes — they are manufactured to Trade series (cam wedge-lock pair), so dimensions are interchangeable between suppliers when you quote the standard on your order.

### What are Wedge-Lock Washer Pairs used for?

Joints under vibration or dynamic load, locked by a cam angle greater than the thread lead rather than by friction. They are supplied to Trade series (cam wedge-lock pair).

### Which industries use Wedge-Lock Washer Pairs?

They are commonly specified in fabrication & metalwork, bolted structural joints and vibration applications, among other sectors.

### Can I get a quote for Wedge-Lock Washer Pairs in the size and material I need?

Yes. Use the technical drawing and quote form on this page to set the size and options, then send the exact configuration to our team for pricing and lead time.

## Related Pages

Product page: [Wedge-Lock Washer Pairs — specifications & sizes](https://engineeringhardware.com/fastener/wedge-lock-washer-pairs/)

### Wedge-Lock Washer Pairs Specification Guides

### Related Fastener Applications