Environmental Effects on Bearings
High temperature often indicates that the bearing has been in an abnormal condition. High temperatures are also detrimental to bearing lubricants. Sometimes bearing overheating can be attributed to the lubricant of the bearing. If the bearing is continuously rotated at a temperature exceeding 125°C for a long time, the life of the bearing will be reduced. Causes of high temperature bearings include: insufficient lubrication or excessive lubrication, lubricant. Bearing contains impurities, the load is too large, the bearing ring is damaged, the clearance is insufficient, and the high friction caused by the oil seal, etc.
Vibration is quite sensitive to bearing damage. Spalling, dents, rust, cracks, wear, etc. are all reflected in bearing vibration measurements. Therefore, the size of the vibration can be measured by using a special bearing vibration measuring device (frequency analyzer, etc.), and the specific situation of the abnormality cannot be deduced through the frequency division.
The measured value is different due to the service conditions of the bearing or the installation position of the sensor, etc., so it is necessary to analyze and compare the measured value of each machine in advance to determine the judgment standard.
What Should We Do?
Select the bearing specifications and precision according to the use part and use environment.
1. Use parts: Tapered roller bearings are suitable for bearing combined radial and axial loads mainly 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. Generally, under normal circumstances, it is advisable to use 0.2 times the limit speed.
3. Allowable inclination angle: Tapered roller bearings generally do not allow the shaft to incline relative to the housing hole, and if there is inclination, the maximum shall not exceed 2′.
4. Permissible temperature: Under the condition of bearing normal load, the lubricant has high temperature resistance and sufficient lubrication, general bearings are allowed to work at the ambient temperature of -30°C-150°C.