Locking Washers

Uses for Lock Washers

While lock washers are commonly used throughout many different industries to hold together critical joints, they're not as common around the home. Here are a few everyday items that might call for a lock washer over a standard washer due to either spontaneous self-loosening or slackening:

• Automotive components
• Household appliances
• Furniture pieces
• HVAC units
• Soft materials (metal, wood, or plastic)

Types of Lock Washers

Listed below are common lock washer types and the applications in which each would be most useful. Lock washers come in various metals, including stainless steel, galvanized steel, zinc-plated steel, and silicone bronze (a brass alloy made of 96 percent copper and stronger than bronze). Use a lock washer material that is the same as the bolt you are securing. However, you will typically use a type of steel lock washer for its corrosion resistance.

1. Split Lock Washer

Split lock washers are washers that have been split, resulting in two opposed edges. These sharp edges slightly dig into each side of the joint and create friction between the bolt and the bolted material, which helps to hold the bolt in place.

2. High Collar Lock Washer

   A high collar is similar to a split washer but much thicker and springier. These washers can be used similarly but they can handle a significantly higher torque load.

3. External Serrated Washer

   External serrated washers look similar to a standard washer, but feature teeth along the edge. The serrated edge creates friction by digging into the materials. These are commonly used for appliances, HVAC units, and various electrical connections.

4. Internal Serrated Washer

   Internal serrated washers work similarly to external serrated washers, only the teeth are on the inside rather than the outside. This makes them suitable for smaller head bolts or instances when the teeth should be hidden.

5. Belleville Washer

   A Belleville washer, otherwise known as a conical spring washer, is a conically shaped washer without splits or serrations. The conical shape makes the washer springy once a load is applied, which protects the bolt's preload and prevents bolt creep.