The performance of the machine tool depends to a large extent on the precision and dynamic performance of the spindle assembly, which is directly related to the installation and adjustment of the spindle bearing.

Rolling bearings for machine tools are precision components, and are particularly sensitive to improper operations during installation and adjustment. If the installation method is not proper, it may damage the 

bearing and destroy the precision of the bearing. If the adjustment is not proper, there will also be poor precision, low rigidity, high temperature, high noise or poor vibration resistance. Therefore, the installation

and adjustment of precision bearings must have a set of strict operating procedures, and appropriate installation and adjustment tools must be prepared.

Preparations before installation

It is recommended that precision bearings be unpacked immediately before installation. The preparatory work before the installation of precision bearings includes the following items.

In order to prevent bearings from rusting during transportation and storage, precision bearings are usually packed with a thin layer of anti-rust oil on the bearing surface. 

In order to prevent poor bearing lubrication due to the incompatibility between lubricating oil or grease and anti-rust oil, it is recommended that precision bearings

 be carefully cleaned after opening the package. If conditions permit, the operator can wear it once. Non-toxic plastic gloves, do not touch the bearing directly with your hands.

Cleaning of bearings

(1) Clean, high-purity gasoline should be used for bearing cleaning fluid, preferably at least No. 90 gasoline;

(2) The cleaning of the bearing can be done in two steps. Prepare two clean containers, pour enough cleaning liquid, and place a metal mesh pad in one of the containers. 

First, soak the bearings taken out of the packing box in a dry container with mesh pads, or use a brush to remove the anti-rust oil film on the surface of the bearings, 

and then perform final cleaning on the bearings in the second container, cleaning while rotating. Note that the cleaning solution should be replaced in time during 

the cleaning process to ensure the cleanliness of the cleaning solution. Sealed bearings are not suitable for cleaning and can be installed and used directly;

(3) After cleaning, the bearing should be air-dried or dried naturally. After the residual cleaning fluid of the bearing is completely air-dried, proceed to the subsequent operation;

(4) If the bearing is lubricated with oil, it should be installed under the condition that the bearing is not rotated as much as possible. If the bearing is grease lubricated, 

proceed with subsequent grease filling and installation procedures;

(5) In order to facilitate the smooth installation of the bearing, it is recommended to apply a thin layer of lubricating oil on the installation surface of the bearing.

For grease-lubricated bearings, if the grease is not selected properly, or the amount of grease injected is not appropriate, or even the method of injecting grease 

is incorrect, it will affect the working state of the bearing and even affect the service life of the bearing. Therefore, it is necessary to strictly formulate the injection procedures of grease.

Injection of grease

(1) Select the appropriate grease and prepare a syringe of appropriate size;

(2) Put the grease into the syringe;

(3) Use a syringe to evenly inject grease into the bearing raceway from between two adjacent rolling elements;

(4) Gently rotate the bearing by hand so that the grease is evenly distributed on the raceway of the bearing, the guide surface of the cage, the surface of the pocket hole of 

the cage and the surface of the rolling body.