How and why you should use a wave spring for bearing preload

A bearing is designed to move freely and has multiple moving parts that work together as one unit. Tolerance stack up from both manufacturing and assembly can quickly cause issues. This is where preloading a bearing comes in. Preloading a bearing involves providing a sustained axial load to the bearing.

There are two main methods to preload a bearing. The first is solid preload, which is achieved by holding inner and outer races in place with a locking mechanism.

The more common, simpler, and less expensive method is spring preload, which is achieved by using a spring to apply a constant axial load on one side. A Smalley single-turn wave spring provides necessary preload force between the inner or outer races while also compensating for any tolerance stack-ups or thermal misalignments. Play is reduced both axially and radially, as depicted in the image below.

Controlling play is necessary to maintain bearing functionality and longevity. Preloading a bearing provides constant contact between the bearing type (ball, needle, etc.) and bearing races. The sustained load provided by the spring eliminates axial and radial play, among other benefits. The overall goal of preloading is to prolong bearing life, and therefore, your application.

Properly preloading a bearing will prolong bearing life. Using a spring for preload is critical for high-precision or high-speed applications, as it essentially eliminates the need for holding tighter tolerances and helps withstand high operating speeds.

Smalley’s bearing preload wave spring SSB series is carefully designed with the application in mind. The two types of single-turn wave springs we offer are gap and overlap.

We have over 300+ standard parts available in carbon steel and stainless steel to match popular bearing sizes.

As always, our engineering team can assist you in designing a custom preload bearing spring for your unique application. Come and find us on stand G55