Tips for quality inspection of bearing operation

After the bearing is installed, it should be checked to ensure that the bearing is installed in place, rotating flexibly and without stagnation. If the bearing is not installed properly, it will cause the bearing temperature to rise rapidly and damage, and even the bearing will be stuck and broken.

First, the rotation sound of the bearing is checked by stethoscope, and there are strong metal noise, abnormal sound, irregular sound, etc. The causes include poor lubrication, poor accuracy of shaft or bearing seat, bearing damage, foreign matter invasion, etc.

Second, the bearing temperature can be inferred from the external temperature of the bearing seat. But it is more accurate to measure the temperature of bearing outer ring directly by oil hole. The temperature of the bearing increases gradually from the beginning of operation, and it is usually stable after 1 ~ 2 hours. If the bearing is not installed properly, the temperature will rise sharply, resulting in abnormal high temperature. The reasons include too much lubricant, too small bearing clearance, poor installation, too much friction of sealing device, etc. In the case of high-speed rotation, the wrong selection of bearing structure and lubrication mode is also the reason.

Third, small machines can be rotated by hand to make sure they rotate smoothly. The inspection items include poor operation caused by foreign matter, scar and indentation, unstable torque caused by poor installation and poor processing of mounting seat, excessive torque caused by too small clearance, installation error and seal friction, etc. If there is no abnormality, power operation can be started.

Fourth, large machinery can not be manually rotated, so immediately cut off the power after no-load start, machine idling, check whether there is vibration, noise, rotating parts contact, etc., after confirming that there is no abnormality, enter the power operation.