Due to the limitations of its working conditions, most coal mining machinery operates underground, with harsh working conditions, long continuous operation time, and narrow mine space. Therefore, coal mining machinery requires a more compact structure and small volume. Coal mining machinery bears significant pressure and load on bearings and gears, leading to bearing failure due to fatigue caused by bearing wear.

The economic losses caused each year are staggering. Only by selecting the correct bearings, conducting regular maintenance, timely maintenance, improving maintenance quality, and ensuring that all production equipment operates in good condition, can we reduce the wear and tear of coal mining machinery, extend its service life, and achieve efficient and safe production of coal. Only then can mining operators ensure high productivity and achieve the expected service life of the equipment.

Double row cylindrical roller bearings have the advantages of compact structure, high rigidity, strong load-bearing capacity, and small deformation after being loaded, and are widely used in various coal mining equipment. The data shows that an increase in its working load will significantly increase the maximum contact load and maximum contact stress between the roller and raceway; As the radial working clearance increases in the positive direction, the maximum contact load and maximum contact stress show a trend of first decreasing and then increasing, and the bearing fatigue life shows a trend of first increasing and then decreasing; There is a specific clearance value that maximizes the fatigue life of the bearing.

Cylindrical roller bearings used in coal mining equipment usually have clearance. When subjected to radial loads, the inner and outer rings will undergo relative displacement in the direction of external forces, causing contact deformation between the bearing roller and the raceway. For double row cylindrical roller bearings, when bearing the working load, it can be considered to evenly distribute the working load between the two rows of rollers.