1. Manual lubrication method
This is the most traditional method and is suitable for situations where the lubricant is insufficient. The lubricant is replenished manually using a refueling device. However, this method is difficult to maintain a stable oil volume and there is a risk of forgetting to refuel, so it is mostly used in situations with light loads, low speeds or intermittent movement. When operating, it is recommended to install a dust cover or ball valve on the refueling hole and use items such as felt, cotton or plush as a filter device.
2. Dripping lubrication method
This method is usually used for light and medium-load bearings with a circumferential speed of less than 4~5m/s. A fixed amount of lubricating oil is supplied through containers, holes, needles, valves and other components. The dripping oil cup is a classic device, but the amount of oil dripping will be affected by many factors such as the viscosity of the lubricating oil, the bearing clearance and the position of the oil supply hole.
3. Oil ring lubrication technology
This technology uses an oil ring that is hung on the shaft and can rotate to bring the lubricating oil in the oil pool to the bearing. However, this method is only suitable for the lubrication of horizontal shafts. For medium-speed and high-speed bearings with a shaft diameter greater than 50mm, the oil ring is preferably seamless. When the bearing width-to-diameter ratio is less than 2, one oil ring can be used; otherwise, two are required.
4. Oil wick lubrication method
This method relies on the capillary and siphon effect of the oil wick to introduce the lubricating oil in the oil cup into the bearing. At the same time, the oil wick can also play a filtering role in the whole process. This method is mainly used for light-loaded and medium-loaded bearings with a circumferential speed of less than 4~5m/s.
5. Oil pad lubrication method
Use the capillary action of the oil pad to apply the lubricating oil in the oil pool to the shaft diameter surface. This method can keep the friction surface clean, but dust may clog the capillary pores, resulting in insufficient oil supply. The oil supply of oil pad lubrication is usually only 1/20 of that of oil lubrication.
6. Oil bath lubrication mode
This method immerses part of the bearing in lubricating oil. It is often used for thrust bearings of vertical shafts, but not for radial bearings of horizontal shafts.
7. Splash lubrication system
This system uses the slapping effect of the rotating parts in the oil tank to supply the splashed lubricating oil to the bearing, which is suitable for bearings with higher speeds.
8. Spray lubrication scheme
This method sprays the lubricating oil onto the friction surface after atomization, which is suitable for high-speed bearings.
9. Pressure oil supply lubrication technology
This technology uses the pressure of the lubrication pump to supply oil to the bearing, and recovers the lubricating oil flowing out of the bearing to the oil pool for recycling. This is the lubrication method with the largest oil supply and the most stable, suitable for high-speed, heavy-loaded and important sliding bearings.
10. Circulating oil lubrication system
This system uses an oil pump to deliver filtered oil to the bearing components, and then filters and cools it after passing through the bearings. Since the circulating oil can take away a certain amount of heat and reduce the bearing temperature, this method is suitable for bearing components with higher speeds.
11. High-pressure oil jet lubrication technology for bearings
An advanced lubrication method is to precisely spray high-pressure oil into the bearing through an oil pump. The oil enters at one end of the bearing, and after being lubricated inside the bearing, it flows into the collection tank from the other end. During the high-speed rotation of the bearing, the rolling elements and the cage drive the surrounding air flow at a very high speed, forming a barrier, making it difficult for conventional lubrication methods to deliver lubricating oil into the bearing. At this time, high-pressure jet technology is needed to deliver lubricating oil directly into the bearing through a nozzle. The precise position of the nozzle should be between the inner ring and the center of the cage to ensure maximum lubrication effect.
