Fill grease. Lubricating oil does not need to be cleaned in general. However, the bearings for instruments or high-speed use should be cleaned with clean oil to remove the rust inhibitor coated on the bearings. Bearings with anti-rust agent removed are easy to rust, so they cannot be left alone. In addition, bearings that have been sealed with grease can be used directly without cleaning.

The installation method of the bearing varies with the bearing structure, fit, and conditions. Generally, because most of the shaft rotates, the inner ring needs an interference fit. Cylindrical bore bearings are usually pressed in with a press or hot-fitting method. In the case of a tapered hole, install it directly on the tapered shaft or install it with a sleeve.

When it is installed in the shell, there is generally a lot of clearance fit and interference in the outer ring. It is usually pressed in with a press or a shrink fit method is also used for installation after cooling. When dry ice is used as the coolant, the moisture in the air will condense on the surface of the bearing when the shrink fit is installed. Therefore, appropriate anti-rust measures are required.

1. Installation of cylindrical bore bearings

(1) Press-fitting method with a press

Small bearings are widely used press-fitting method. Pad the spacer block into the inner ring, and press it statically with a press until the inner ring is in close contact with the shoulder of the shaft. Mounting the outer ring with a spacer block to install the inner ring is the cause of indentation and crushing on the raceway, so it is absolutely forbidden.

During operation, it is best to apply oil to the mating surface in advance. If you must use a hammer to install, you must put a block on the inner ring. This practice has repeatedly become the reason for bearing operation, so it is limited to the case of small interference and cannot be used for large interference, or medium and large bearings.

For non-separable bearings such as deep groove ball bearings, where the inner ring and outer ring need to be installed with interference, use a spacer block to pad, use a screw or oil pressure to connect the inner ring and the outer ring. The ring is pressed in at the same time. The outer ring of self-aligning ball bearing is easy to tilt, even if it is not an interference fit, it is best to install it with a pad.

For separate bearings such as cylindrical roller bearings and tapered roller bearings, the inner ring and outer ring can be installed on the shaft and housing respectively, and the installed inner ring and outer ring can be compared with each other. When combining, the key is to steadily close the two, so that the center of the two does not deviate, and pressing in will cause the raceway surface to jam.

(2) Method of hot-fitting

Large bearings require a lot of force when pressed in, so it is difficult to press in. Therefore, the hot fitting method of heating the bearing in oil to expand it and then installing it on the shaft is widely used. Using this method, the operation can be completed in a short time without adding improper force to the bearing.

The heating temperature of the bearing is based on the bearing size and the required interference. The precautions for hot fitting are as follows:

(a) Do not heat the bearing above 120°C;

(b) In order to prevent the bearing from directly contacting the bottom of the oil tank, it is best to consider Put the bearing on the metal mesh table, or hoist the bearing;

(c) Heat the bearing to 20℃-30℃ higher than the required temperature so that the inner ring does not become cold during operation. Difficult to install;