The oil groove of the bearing is primarily used in conjunction with grease lubrication to replace lip seals, especially in environments with a large amount of dust. This sealing method typically features several oil grooves on both the inner and outer diameters. These grooves become filled with a mixture of dust and grease, which hardens over time, sealing the oil grooves tightly. When oil lubrication is applied, the oil grooves disrupt capillary action, preventing the lubricant from overflowing from the bearing cavity. These grooves can also be spiral-shaped to recirculate the lubricant back into the bearing cavity, but this is only applicable when the axis is horizontal and rotating in the same direction.

When machines operate in extremely dirty environments, the oil sump with labyrinthine sealing will more effectively protect grease-lubricated bearings.

This type of sealed *** is effective when using very small gaps and a certain number of oil grooves.