Infrared instruments for astronomy require many bearings for motion that must move in cryogenic conditions. There are poor and expensive options for this, and the companies with qualified bearings only supply after a long time. To attend these constrains, the Instituto de Astrofísica de Canarias (IAC) started to develop a procedure to upgrade commercial bearing to operate to cryogenic conditions.



The initial attempts involved sprinkling molybdenum disulfide (MoS2) inside the bearing without disassembling it after cleaning. However, this method prevented uniform lubrication, leading to potential failures. The IAC mechanical team diligently refined the procedure, which included disassembling the bearings and replacing the cage by a technical polyamide cage.



This innovative approach significantly enhances efficiency; however, it comes at a higher cost due to high price of some technical polyamides such as Vespel. Additional research and testing have demonstrated that the pre-lubrication the bearing races with MoS2 significantly increases bearing life, although it involves a laborious process.



In recent years our focus has been on exploring more cost-effective material and how to improve bearing life.



This presentation discusses these techniques and the selected material for bearing preparation and presents the results of the latest cryogenic temperature life tests conducted on the produced bearings, along with the conclusions reached.