Usually the bearing and the shaft are used together, the bearing inner sleeve and the shaft are installed together, and the bearing jacket and the bearing seat are installed together. If the inner sleeve rotates with the shaft, the inner sleeve and the shaft are closely matched, and the bearing jacket and the bearing body are gap matched; On the contrary, if the bearing body and the bearing jacket turn together, the bearing jacket and the bearing body are closely matched, and the bearing inner sleeve and the shaft are gap matched. In the process of operation, lap running faults often occur, which needs analysis and treatment, or it will cause accidents, resulting in large losses
Reasons for running bearings:
1. Poor coordination
shaft
Running laps is a common fault, and the causes of running laps are various. First is mismatch, we know that running bearings will produce heat, axis and inner sleeve, coat and bearing body there is a difference in temperature, the temperature difference causes with the changes of firmness, if closely bearing inner sleeve size is greater than the shaft diameter, with the extension of time, will generate wear, run laps is inevitable, and will send out more heat, The temperature of the bearing body will also increase, once the bearing body expands, the bearing clearance disappears, the inner and outer sleeve of the bearing becomes an integral whole, with the shaft rotating, then the bearing jacket is doing rotating movement in the bearing body, and generates a lot of heat, and the accident occurs, and the inner hole of the bearing body is also ground large. This is the temperature difference
Running laps caused by improper tightness.
2. Laps caused by vibration
Vibration is run laps, if the equipment vibration is larger, the greater the bearing load bearing of east, shaft is like being in operation, over time, the shaft will be beat, journal and it destroyed the original firmness, formed the micro, fever, run laps, journal will mill, mill bearing hole in the body will be big.
3. Lubrication failure
Lubrication failure. When lubrication fails, the friction generates more heat, the temperature difference between the inner and outer sleeve of the bearing and the bearing body is large, which destroys the original fit size, and the bearing journal and bearing body wear.
4. Improper selection of lubricating oil
Lubricating oil selection is improper or even more impurities. When large grease hardness or impurities, will cause bearing rolling body cavity effect, stop rolling element has its own spin, friction heat, it will also drive the coat on the choice of bearing body, wear, when the resistance is bigger, the resistance can overcome the friction of the bearing inner sleeve on the shaft, the shaft from the inner sleeve slip, slide, causing wear and tear.
5. Improper installation
Improper installation. Improper installation mainly refers to such as bearing heating temperature is too high, bearing expansion, size can not be returned; The remaining clearance of the free end bearing of the shaft is insufficient, resulting in heat generation by friction on the side of the bearing; Bearing, shaft, bearing body cleaning is not clean, resulting in stuck; Split the bearing seat and press the bearing flat, resulting in poor conditions such as local stagnation of the bearing, which will cause bearing heating, leading to bearing running.
6. Chronic vibration
Long-term vibration and percussion will make the shaft fatigue spalling, once the debris is discharged, it will inevitably cause loosening, resulting in bearing running laps.
7. Bearing failure
Bearing failure. Bearing running for a long time, the raceway will produce point fatigue pitting corrosion, falling debris will produce weir effect, once heating, temperature difference will be generated at the same time, it will cause running laps.
Post time: Mar-18-2022