Inspection before operation of mining machinery bearings
After the bearing is installed, in order to ensure the smooth operation of the bearing, the inspection work before the bearing operation should be paid attention to.
For small machines, you can directly rotate the bearing by hand to see if it can run smoothly. In daily inspection operations, common poor operation phenomena mainly include: poor operation due to foreign objects, scars and indentations; poor operation due to improper installation; large installation errors due to too small clearance, etc. The reason is that the torque is too large, resulting in poor operation of the bearing, etc. If no abnormality is found after careful inspection, the bearing can be used for the next step of power operation.
For large machinery, manual rotation is not possible, but inertial operation can be carried out by stopping the power in time after starting without load, and then carefully observing the vibration and noise of the bearing and the actual contact of each rotating part to confirm that there is no After the abnormality, the next power rotation stage can be carried out.
Power rotation, this stage generally starts from the no-load low-speed stage and gradually increases to the rated operating speed. During the trial operation stage, the focus should be on checking: whether there is abnormal sound in the bearing, whether there is lubricant leakage, and whether the bearing has a large temperature rise change, etc. If an abnormality occurs during the trial operation of the bearing, the bearing should be carefully inspected even if the operation is stopped, and the bearing should be disassembled and inspected if necessary.
The temperature rise of the bearing can usually be known by inspecting the bearing housing, but it is also possible to directly inspect the temperature of the outer ring of the bearing with the aid of the oil filling hole, so that the inspection result obtained will be more accurate. The bearing temperature of mining machinery generally rises gradually from the beginning of the bearing operation, and the bearing temperature usually tends to stabilize after rising to a certain temperature. If the bearing is installed improperly, it may cause the bearing temperature to rise sharply and produce abnormal temperature rise. In addition, excessive bearing lubricant, too small internal free gap, severe wear of the ball, high-speed rotation, etc., may also cause a transitional temperature rise of the bearing.