Lubrication
SKF inch roller bearing units are intended for grease lubrication.
Initial grease fill
SKF inch roller bearing units are filled with a mineral oil based lithium grease that contains EP additives. The initial grease fill at the factory fills the bearing completely and 40 to 50% of the free space in the housing. The technical specifications of the grease are provided in table 1. The grease provides reliable performance when operating between 95 and 230 °F. During start-up, temperatures down to –5 °F are permissible. For short periods, temperatures above 230 °F can be tolerated.
For additional information about permissible temperatures of rolling bearing greases, refer to Temperature range – the SKF traffic light concept.
Relubrication
SKF inch roller bearing units are typically relubricated in order to realize maximum service life. All bearing units except those in the FYRP series have a lubrication hole with a 1/8-27 NPSF thread. They are provided standard with a grease fitting AH 1/8-27 PTF. Units in the FYRP series have a 1/4-28 UNF straight thread, and are provided with a grease fitting 1/4-28 UNF.