If rolling bearings are to operate reliably they must be adequately lubricated to prevent direct metal-to-metal contact between the rolling elements, raceways and cages .

A wide selection of greases and oils is available for the skf bearing lubrication of rolling bearings and there are also solid lubricants,for extreme temperature conditions. The actual choice of a lubricant depends primarily on the operating conditions,that is to say,the temperature range and speeds as well as the influence of the surroundings.

The skf bearing lubricant also inhibits wear and protects the bearing surfaces against corrosion. The choice of a suitable lubricant and method of lubrication for each individual bearing  application is therefore important, as is correct maintenance. 

The most favorable operating temperatures will be obtained when the minimum amount of lubricant needed for reliable bearing lubrication is provided. However, when the lubricant has additional functions, such as sealing or the removal of heat, additional amounts of lubricant may be required. 

The skf bearing lubricant in a bearing arrangement gradually loses its lubricating properties as a result of mechanical work, ageing and the build-up of contamination. It is therefore necessary for grease to be replenished or  renewed and for oil to be filtered and changed at regular intervals.

The information and recommendations in this article relate to bearings without integral seals or shields. The principles of lubrication of plain or sleeve-type bearings are not considered as well. The article is based on relevant, recent SKF publications .