Bearing lubrication is to enable bearings to operate normally, avoid direct contact between raceway and the surface of the rolling body, reduce friction and wear inside bearings, extend the service life of bearings, enhance the performance of bearings, and prevent rust and corrosion caused by foreign body intrusion inside bearings. The following are 11 commonly used lubrication methods for bearings.

 

First, manual lubrication

 

This is the most original method, in the case of insufficient lubricating oil in the bearing, the oil is supplied by the oiler. However, this method is difficult to keep a certain amount of oil, due to negligence and forget the risk of refueling is larger, usually only used for light load, low speed or intermittent movement of the occasion, the best operation, in the refueling hole set dust cover or ball valve, and with felt, cotton, wool as a filter device.

 

Two, drop point lubrication

 

It is usually used for light load and medium load bearings with circular velocity less than 4 ~ 5m/s. It supplies roughly quantitative lubricating oil from the container through the hole, needle and valve, etc. The most classic is the drip oil cup. The drip oil amount varies significantly with the viscosity of lubricating oil, bearing clearance and the position of the oil supply hole.

 

Three, oil ring lubrication

 

The lubricating oil from the oil pool is brought to the bearing by the ring that is hung on the shaft and can be rotated (can only be used for horizontal shaft lubrication method). It is suitable for medium speed and high speed bearings with axle diameter greater than 50mm. The oil ring should be seamless.

 

Four, oil rope lubrication

 

The lubricating oil in the oil cup is led to the bearing by the capillary and siphon action of the oil rope, which is mainly used for light and medium load bearings with circular velocity less than 4 ~ 5m/s. In addition, the oil rope can play a filtering role in the whole process.

 

Five, oil pad lubrication

 

Using the capillary action of the oil pad, the lubricating oil in the oil pool is applied to the axial diameter surface. This method can keep the friction surface clean often, but the dust will block the capillary pores and cause insufficient oil supply. The oil supply of oil pad lubrication is usually only 1/20 of that of oil lubrication.

 

Six, oil bath lubrication

 

This lubrication method is to dip a part of the bearing into the lubricating oil, which is often used for vertical shaft thrust bearings, but not suitable for horizontal shaft radial bearings.

 

Seven, splash lubrication

 

The spattered lubricating oil supplied to the bearing by the tap of the rotating part in the tank is suitable for the bearing with higher speed.

 

Eight, spray lubrication

 

The lubricating oil is atomized and sprayed on the friction surface, which is suitable for high-speed bearings.

 

Nine, pressure oil supply lubrication

 

Oil is supplied to bearings by the pressure of lubrication pump, and the lubricating oil discharged from bearings is recovered to the oil pool for recycling. It is the most stable lubrication method with the largest oil supply and is suitable for high-speed, heavy-duty and important sliding bearings.

 

Ten, circulating oil lubrication

 

The filtered oil is transported to the bearing parts with the oil pump, and the lubricating oil after the bearing is filtered and cooled before use. Because the circulating oil can take away a certain amount of heat and cool the bearing, this method is suitable for the bearing parts with higher speed.

 

 

 

The oil pump is used to shoot the high-pressure oil into the bearing through the nozzle, and the oil in the bearing flows into the oil groove through the other end of the bearing. When the bearing rotates at a high speed, the rolling body and the cage also make the surrounding air flow at a relatively high rotation speed. It is difficult to send the lubricating oil to the bearing with the general lubrication method. At this time, the lubricating oil must be sprayed into the bearing with the method of high pressure injection.

 

Bearing lubrication is a continuous work, and the replacement cycle of lubricating oil is based on the service conditions of bearings and the amount of oil. Under normal circumstances, when the operating temperature is below 50℃ and the dust is less, it is replaced once a year. When the oil temperature reaches 100℃, it is replaced once in 3 months or less.