Ball Bearing Preload Disc Springs are basically designed to use with radial Ball Bearings. They help with maintaining accuracy and positioning of the Bearing with no end play. They also assist with vibration and shaft deflections.
Using this type of Disc, will help increase the rigidity of a Bearing and help reduce noises.
These Preload Disc Springs are available to purchase online, please click this link: https://springfasteners.co.uk/product-category/disc-springs/ball-bearing-pre-load-disc-springs/