Although the products of many manufacturers are utilised, there are three basic greases used for turbine plant:
- Silicone-based grease containing molybdenum disulphide. This has a working range of - 50°C to 300°C.
- Mineral oil with Bentone filler; this grease has a slightly lower temperature limit of 260°C.
- Lithium-based grease. These greases are used for a wide range of lubricating duties including ball and roller bearings. The requirements for the testing of this type of grease are laid down in CEGB Standard No. 207001.
The first two greases listed are for the lubrication of high temperature sliding surfaces, such as turbine palms and steam valve pivots.