More than 50 percent of bearing failure is caused by improper lubrication, so in the early design of the roller shaft, bearing lubrication should be given high attention. Roller bearings are generally lubricated by grease instead of oil. The steps for selecting grease are as follows:
1. Determine the consistency grade of the grease. According to DIN 518-1981, grease is divided into different viscosity classes according to the NLGL standard. The higher the NLGL class is, the thicker the grease is. Lubricating grease consistency of roller bearing is nlgi-3.
2. Select additives. According to the requirements of the conveyor function and working conditions to choose the appropriate grease additives. Commonly used additives are extreme pressure antiwear agent, anti - corrosive agent, solid lubricant and special additives.
3. Determine the viscosity of base oil. The viscosity of the base oil determines the fluidity of the base oil. The higher the viscosity of the base oil, the thicker the base oil will be. In order to form the elastohydrodynamic lubrication film and separate the metal parts of the bearing seat, the base oil with appropriate viscosity must be selected according to the specific working condition. The viscosity of the base oil determined shall match the viscosity of the selected grease.
Choosing the proper grease can improve the service life of the bearing, at the same time regularly supplement the grease to prevent dust into the bearing, ensure the normal work of the bearing, extend the service life of the bearing plays a very important role.