1. Bearing installation:
The installation of bearings must be carried out under dry and clean environmental conditions. Before installation, carefully check the processing quality of the mating surface of the shaft and the housing, the end face of the shoulder, the groove and the connection surface. All mating connection surfaces must be carefully cleaned and deburred, and the unprocessed surface of the casting must be cleaned of molding sand.
Bearings should be cleaned with gasoline or kerosene before installation, used after drying, and well lubricated. Bearings are generally lubricated with grease or oil. When using grease lubrication, grease with excellent properties such as no impurities, anti-oxidation, anti-rust, and extreme pressure should be selected. The filling amount of grease is 30%-60% of the volume of the bearing and bearing box, and it should not be too much. The double-row tapered roller bearings with sealed structure and the shaft-connected bearings of the water pump have been filled with grease and can be used directly by the user without further cleaning.
When installing the bearing, it is necessary to apply equal pressure on the circumference of the end face of the ferrule to press the ferrule in. Do not directly hit the end face of the bearing with a hammer or other tools to avoid damage to the bearing. In the case of small interference, the sleeve can be used to press the end face of the bearing ring at room temperature, and the sleeve can be tapped with a hammer head to press the ring evenly through the sleeve. If it is installed in large quantities, a hydraulic press can be used. When pressing in, it should be ensured that the end face of the outer ring and the shoulder end face of the shell, and the end face of the inner ring and the shoulder end face of the shaft are pressed tightly, and no gap is allowed.
When the interference is large, the bearing can be installed by heating in an oil bath or by an inductor. The heating temperature range is 80°C-100°C, and the maximum cannot exceed 120°C. At the same time, nuts or other appropriate methods should be used to fasten the bearing to prevent the bearing from shrinking in the width direction after cooling, resulting in a gap between the ring and the shaft shoulder.
Clearance adjustment should be carried out at the end of single row tapered roller bearing installation. The clearance value should be determined specifically according to different operating conditions and the size of the interference fit. When necessary, tests should be carried out to confirm. The clearance of double-row tapered roller bearings and water pump shaft bearings has been adjusted before leaving the factory, and there is no need to adjust them during installation.
After the bearing is installed, the rotation test should be carried out. First, it is used for the rotating shaft or the bearing box. If there is no abnormality, it will be powered for no-load and low-speed operation, and then gradually increase the rotation speed and load according to the operation situation, and detect noise, vibration and temperature rise. , found abnormal, should stop and check. It can be delivered for use only after the running test is normal.
2. Bearing disassembly:
When the bearing is dismantled and intended to be used again, an appropriate dismounting tool should be selected. To disassemble a ring with an interference fit, only the pulling force can be applied to the ring, and the disassembly force must not be transmitted through the rolling elements, otherwise the rolling elements and raceways will be crushed.
3. The use environment of bearings:
The selection of specifications, dimensions and precision according to the location of use, service conditions and environmental conditions, and the matching of appropriate bearings are the prerequisites for ensuring the life and reliability of the bearings.
1. Use parts: Tapered roller bearings are suitable for bearing combined radial and axial loads mainly based on radial loads. Usually, two sets of bearings are used in pairs. They are mainly used in front and rear hubs of automobiles, active bevel gears, and differentials. Gearbox, reducer and other transmission parts.
2. Permissible speed: Under the condition of correct installation and good lubrication, the allowable speed is 0.3-0.5 times of the limit speed of the bearing. Under normal circumstances, 0.2 times the limit speed is the most suitable.
3. Allowable inclination angle: Tapered roller bearings generally do not allow the shaft to incline relative to the housing hole. If there is inclination, the maximum shall not exceed 2′.
4. Permissible temperature: Under the conditions of bearing normal load, lubricant with high temperature resistance and sufficient lubrication, general bearings are allowed to work at an ambient temperature of -30°C-150°C.