In order to make the one-way needle roller bearing work normally, it must be effectively lubricated to prevent metal-to-metal contact between the rotating elements, raceways and cages. Therefore, the most important effect of adding lubricant is to separate these surfaces.
Lubricants can also protect the bearing surface from corrosion. In addition to its other functions, the lubricant can also provide a seal against contaminants, or as a heat transfer medium. Choosing the right lubricant for each bearing is very tight.
The working conditions will determine the correct selection of lubricants, that is, temperature limitations, speed and surrounding conditions. Please note that because the lubricant in the bearing arrangement fails its function due to work, aging and dirt storage, it needs to be replaced and updated regularly to achieve proper bearing performance. This is called "relubrication".
Oil is usually used to lubricate one-way needle roller bearings at high speeds, high temperatures, or when heat must be removed from the bearing location. The very tense characteristic of lubricating oil is its viscosity. The viscosity of lubricating oil is directly related to the thickness of the oil film that it can produce. The thickness of the oil film is a very important part of the separation between the rotating surface and the sliding surface of the bearing.
Mineral oil is usually used for the lubrication of one-way needle roller bearings, with rust inhibitors and oxidation inhibitors as increasing agents. In extreme situations such as extremely low or extremely high operating temperatures, consider using synthetic oil for lubrication.
Oil lubrication techniques for one-way needle roller bearings:
Oil bath: can be used for medium and low speeds. The oil stays in the oil sump at the bottom of the bearing, and as the bearing twists, the oil is distributed, and then flows back to the oil bath at the bottom.
Oil collecting ring: Regarding bearings that operate at higher speeds and temperatures, the oil collecting ring transports oil by loosely hanging on the shaft and twisting with the shaft to circulate the oil. Then, the oil flows through the bearing back to the oil tank at the bottom.
Circulatory system: This technique is the first choice in high-speed maneuvers. Under the auspices of the pump, the oil circulates to the bearings, drains and returns to the tank, where it is filtered and cooled before returning to the bearings.
Injector: used in very high-speed applications, where the injector under high pressure points to the side of the bearing. For this reason, the speed of the injector must be high enough to break the turbulence around the torsion bearing.
Oil mist: It is only used under exceptional conditions today, and oil and air under proper pressure are supplied to the bearing box.
Oil spot method: Use compressed air to simply transport the lubricating oil to the bearing. The oil is sent to the air supply pipe of the bearing box at a set time interval.

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