We all know that grease has good adhesion, wear resistance, temperature resistance, rust resistance and lubricity, can improve high temperature oxidation resistance, delay aging, can dissolve carbon deposits, and prevent metal wear debris and oil stains. Poly, to improve the wear resistance, pressure resistance and corrosion resistance of machinery, it will be commonly used in bearing products. For sealed bearings, appropriate grease has been filled during production; for open bearings, a sealing device is also installed in the host to prevent grease leakage. Today, the editor will talk to you about the impact of the amount of bearing grease on the bearing?
The amount of grease injected into the bearing will have a certain impact on its operation. If the amount of grease is too small, it is easy to cause lack of grease or dry friction, which will affect the life span. Too much grease will cause the bearing temperature to rise. A large amount of grease leakage not only pollutes the environment, but also causes waste. It can be seen that the amount of grease injected into the bearing should be as small as possible on the premise of ensuring sufficient lubrication of the bearing.
After understanding the movement process of grease in the bearing, it will naturally come to a conclusion: the grease in the bearing should not be too much. Too much grease is not only a waste, but also harmful. The higher the speed of the bearing, the greater the harm.
The more grease is filled, the greater the friction torque. With the same filling amount, the friction torque of the sealed bearing is greater than that of the open bearing. After the grease filling amount is equivalent to 60% of the internal space volume of the bearing, the friction torque no longer increases significantly. This is because most of the grease in the open bearing has been squeezed out, and the grease in the sealed bearing has also leaked out.
With the increase of the grease filling, the temperature rise of the bearing increases linearly. The temperature rise of the sealed bearing is higher than that of the open bearing at the same filling amount.
It is generally believed that the grease filling amount of sealed rolling bearings should not exceed about 50% of the internal space. Tests have shown that 20% to 30% of ball bearings is appropriate.
Correct lubrication and regular maintenance can avoid bearing damage caused by lubrication problems. To ensure reasonable lubrication:
• Follow the instructions set by the device manufacturer for each device;
• When adding grease, it should be filled between the rolling parts of the bearing and the housing (or retainer) to ensure that sufficient grease enters and the surface of the key raceway is fully lubricated;
• Pay attention to when the bearing should be greased (Re-lubrication);
• Monitor the indicating instruments of the equipment, so as to find signs of problems as early as possible, such as temperature fluctuations and/or abnormal high temperatures;
• Pay attention to equipment noise or abnormal vibration;
• Observe lubricating oil leakage;
• Regularly sample the lubricating oil and check for contamination.
When injecting grease in addition, the site should be clean and clean, and the tools used should be cleaned with gasoline. After the grease is filled, other parts should be assembled as soon as possible to prevent the grease entering the bearing from entraining dust and sundries, especially sand and iron filings.