What types of lubrication can be used for pump bearings?
There are many bearing types, which require different lubrication methods. This response focuses on the most common methods for lubricating rolling element bearings in horizontal process pumps and their application considerations include:
Grease lubrication: An advantage of grease lubrication is simplified maintenance, and some disadvantages are over-pressurization and limited heat dissipation. The use of grease is primarily limited to lower speed and horsepower pumps.
Oil splash: Some advantages of oil bath/splash lubrication are a wider range of speeds than grease and visual verification of oil level is possible, and some disadvantages are sensitivity to oil level and contaminants remaining in the oil bath. Oil splash lubrication can be achieved by the bearing being in direct contact with the oil, oil rings contacting the lubricant and splashing it throughout the bearing housing, or slinger disks that splash the lubricant throughout the bearing housing.
Pure oil mist: Some advantages of pure oil mist lubrication are lower operation temperature compared to oil bath, wear particles are not recirculated and lower oil consumption. Some disadvantages are that it requires higher level of application knowledge and higher initial costs compared to oil bath. The basic concept of oil mist lubrication system is dispersion of an oil aerosol into the bearing housing. There is no reservoir of oil in the housing, and oil rings are not used. The oil is atomized and airflow transports the small oil particles through a piping system into the pump bearing housing.