7 Useful Common Bearing Oil Lubrication Methods [Right Now]

For rolling bearings, bearing oil lubrication is an important issue that affects their performance. The appropriateness of the lubricant or lubrication method will greatly affect the bearing service life. There are 7 common bearing lubrication methods below.

1. Oil cup drip oil lubrication

A method of lubricating the bearing by dripping oil through the oil-saving port in the oil cup.

The advantages of oil cup oil drop lubrication are simple structure, convenient use, and fuel-saving. In addition, you can adjust the oil supply by the fuel-saving port. Generally, the amount of oil drip is preferably one drop every 3-8 seconds. Because excessive oil quantity will cause the bearing temperature to rise.

The disadvantage is that there is a certain requirement for the viscosity of the lubricating oil. It is not possible to use a lubricating oil with high viscosity and there is no heat dissipation function. Oil cup drip oil lubrication is suitable for low-speed and light-load working conditions.

2. Bearing oil bath (oil immersion) lubrication

A method of lubricating the bearing part by immersing it in the lubricating oil and bringing the oil into the other parts of the bearing after it runs. Oil bath lubrication is one of the most common and simple lubrication methods.

Considering the stirring loss and temperature rise during the oil bath lubrication. For horizontal shafts, it's better to limit the bearing part height intruding into the lubricating oil. Generally, control the oil level the center of the lowest bearing rolling body. Oil bath (oil immersion) lubrication, sufficient lubrication, but the oil supply is not easy to adjust. If there is no filtering device in the oil tank, it is easy to bring impurities into the bearing to damage the bearing. The oil bath (oil immersion) is generally suitable for low or medium speed applications. It is more common to use with low-speed bearings.

Experience: Mount the detachable stiffeners on the bottom of the housing to reduce agitation and heat dissipation. You should low the static oil level than the lowest bearing rolling element center of applied to the horizontal axis. For the vertical axis, the static oil level should cover 50% -80% of the rolling elements. If the bearing temperature of the oil bath system is relatively high, you can use the dripping method, splashing or circulating oil system.

3. Splash lubrication

A method of lubricating oil that is splashed into the bearing by other running parts.

The amount of splash lubrication oil supply is not easy to adjust, and the lubricating oil surface should not be too high, otherwise, it is easy to produce stirring loss and temperature rise, and it is easy to bring impurities in the oil tank into the bearing to damage the bearing.

In splash lubrication, splash the oil onto the bearing through a rotating body (impeller or "slinger") mounted on the shaft, and don't immerse the bearing in the oil.

Experience: In gearboxes, gears and bearings often share a fuel tank with gears that serve as slingers. As the viscosity of gear oil may be different from the requirements of the bearing. And the oil contains wear particles from the gear, a separable lubrication system or method can improve the bearing life.

4. Circulating bearing oil lubrication

Suck the lubricating oil from the oil tank by the oil pump and then transported to the bearing where it needs lubrication. Then return it to the oil tank from the oil return port and filtered and reused.

Make the circulating oil fully lubricated, oil supply is easy to control, and heat dissipation and impurity removal ability are strong. Circulating oil lubrication is suitable for occasions with the purpose of dissipating heat or removing impurities, as well as occasions with high speed, high temperature, and heavy load, and has high reliability. It is an ideal lubrication method. However, you will also require a separate oil supply system, and the manufacturing cost is relatively high. The oil supply system consists of oil pumps, coolers, filters, oil tanks, and oil pipelines. This type of lubrication includes oil injection lubrication, forced lubrication, and spray lubrication. They have different angles.

5. Oil mist rolling bearings lubrication

Put the oil in an oil mist generator, using compressed air and a small amount of lubricating oil to form an oil mist and then transporting it to the bearing lubrication part.

Oil mist lubrication has a small stirring loss and temperature rise, saves fuel, and has fewer impurities in the oil. Moreover, the airflow generated during oil mist spraying has a certain cooling effect, and can effectively prevent impurities from invading or discharging impurities. However, the cost of the lubrication device is relatively high, and there are certain requirements for the viscosity of the oil used. Generally, it isn't higher than 340㎜2 / s, otherwise, it will not achieve the atomization effect. In addition, if the seal is not tight during lubrication, some oil mist may escape into the air and pollute the environment. If necessary, use an oil-gas separator to collect the oil mist. Oil mist lubrication is suitable for high-speed applications.

6. Oil injection lubrication method

Bearing lubrication method by injecting lubricating oil into the bearing using a high-pressure injection method. When the bearing is running at a high speed, the rolling elements and the cage rotate at a relatively high speed. Thereby forming an air vortex around the bearing. If you use the general lubrication method, the lubricant will not easily reach the lubrication point. On the other hand, due to the centrifugal force generated at high speed, it is difficult for the lubricating oil to remain in the lubricated part. In order to ensure that a sufficient amount of lubricant is not supplied to the high-speed running bearing. You must force the lubricant in from one end of the bearing for lubrication, and then re-flow into the fuel tank from the other end.

When designing the lubrication system, locate the high-pressure nozzle position between the inner ring and the center of the cage. And throw the lubricating oil to the outer raceway by centrifugation. In order to lubricate the bearings effectively, the spraying speed of the lubricating oil should not be lower than 15m / s.

From the perspective of operating speed, oil injection lubrication is often used for bearings running at high speeds under low or medium loads. From the bearing force perspective, oil injection lubrication is often used for bearings on vertical or inclined shafts.

7. Oil-air method

Oil-air lubrication is usually suitable for the occasion where the bearing runs at a high speed. The oil-air lubrication system mixes a small amount of lubricating oil with a certain pressure of the gas. And then supplies it to the bearing. This method is suitable for high-speed applications, such as machine tools, which people generally less use in the refining and chemical industries