A Guide to Choosing the Best bimetallic washer for Your Project

When it comes to construction and engineering projects, ensuring that every component is of high quality is essential to ensure safety and longevity. One such component that needs special attention is the washer, a tiny yet crucial piece of hardware in any build. With a range of washers available in the market, selecting the right one for specific applications is essential. One of the most popular and reliable options is the bimetallic washer.

If you’re considering using Bimetallic Washers for your project, this guide will walk you through everything you need to know to make the best washer selection.

What is a Bimetallic Washer?

A bimetallic washer is a small, thin disk of two metal layers bonded together. It’s used in many mechanical assemblies as a spacer or cushion to reduce friction. These washers are usually made with two metals with different thermal expansion coefficients, so when the temperature changes, one layer will expand or contract more than the other, creating a tension force between them. This tension helps to keep the assembly tight and secure under changing conditions. The most common applications for bimetallic washers include electrical connections and sealing joints against leakage in plumbing and hydraulic systems. Bimetallic washers can reinforce structures subject to vibration or shock, such as automotive engines or fuel tanks. They can also be used to insulate components from heat transfer by creating an air gap between metal surfaces at high temperatures – this application is known as thermal counteraction technology (TCT).

A bimetallic washer is a flat washer made using two different metals with different thermal expansion coefficients. These metals are bonded during manufacturing and designed to accommodate thermal expansion and contraction during temperature changes.

Benefits of Using Bimetallic Washers

The primary benefit of using bimetallic washers is their ability to withstand extreme temperature changes. These washers can prevent damage to other assembly components by creating a buffer and reducing stress caused by thermal expansion.

With bimetallic washers, you can be assured longevity and durability even in harsh conditions. Their construction also enhances electrical conductivity, corrosion resistance, and protection against bacteria and fungi.

Factors to Consider When Choosing Bimetallic Washers

When selecting a bimetallic washer for your project, various factors need to be considered:

Material Choice: 

Different metals have unique properties that can impact the function of the washer. Understand the environment where the washer will be used and choose a combination of metals to offer the best resistance to the expected environment.

Size and Shape:

The size and shape of the washer can affect its performance in various ways. For example, a larger diameter washer will offer better stress distribution than a smaller one.

Load and Tolerance:

 Consider the weight the washer will bear, the pressure expected on the washer, and the degree of flex the washer will require. A thorough understanding of load and tolerance will ensure an appropriate washer choice.


The cost of a bimetallic washer will vary depending on the type and combination of metals used. You should balance the quality of the washer with the price, as this will help prevent over or under-engineering the project.

Installation Requirements of Bimetallic Washers

During installation, you should avoid over-tightening the washers, which may cause them to crack or deform. Ensure that you use the right tool, and depending on the application, consider applying a final torque.


Bimetallic washers offer incredible temperature management, corrosion resistance, and durability, making them the go-to option for most engineering and construction projects. With various factors to consider during the selection process, an educated decision-making strategy ensures the right bimetallic was her choice for the project. Follow best practices during installation and operations to maximize the washer’s lifespan and improve efficiency in the project.