After the installation of the INA
bearing is completed, in order to check whether the installation is correct, the operation check is required. The small machine can be rotated by hand to confirm whether the rotation is smooth. The inspection items have poor operation due to foreign matter, scratches, and indentations. The installation is poor, the torque generated by the mounting is not stable, and the torque is too large due to too small clearance, installation error, and sealing friction. Wait. If there is no abnormality, the power running can be started.
Large machinery cannot be rotated manually, so the power is cut off immediately after the start of the no-load, the machine is idling, and the presence or absence of vibration, noise, and contact of the rotating parts is checked. After confirming that there is no abnormality, the power is turned on.
The power running starts from the no-load low speed and slowly increases to the rated operation of the specified conditions. The items to be checked during the test run are whether there is abnormal sound, change in the bearing temperature of the INA bearing, leakage or discoloration of the lubricant, and the like. If an abnormality is found, stop the operation immediately, check the machine, and remove the bearing check if necessary.
INA imported bearing temperature, generally can be estimated based on the external temperature of the bearing housing. However, it is more accurate to directly measure the temperature of the outer ring of the bearing by using the oil hole. The bearing temperature gradually rises from the start of the operation, and the temperature is usually stable after 1 to 2 hours. If the bearing is poorly installed, the temperature will rise sharply and an abnormally high temperature will occur. The reasons are such as excessive lubricant, too small bearing clearance, poor installation, excessive friction of the sealing device, and the like. In the case of high-speed rotation, the selection of INA imported bearing structure and lubrication method is also the reason.
The rotation of the INA bearing is checked with a stethoscope, etc., and there are strong metal noise, abnormal sounds, irregular sounds, etc. The reasons are poor lubrication, poor accuracy of the shaft or housing, bearing damage, and foreign matter intrusion.
The common faults of INA imported
bearings are as follows:
1, tile surface corrosion: spectral analysis found that the concentration of non-ferrous metal elements is abnormal; there are many sub-micron wear particles of non-ferrous metal components in the iron spectrum; lubricating oil moisture exceeds the standard, acid value exceeds the standard.
2, the surface of the journal is strained: there are iron-based cutting abrasive grains or black oxide particles in the iron spectrum, and there is tempering color on the metal surface.
3, the surface corrosion of the journal: Spectral analysis found that the concentration of iron is abnormal, there are many sub-micron particles of iron in the iron spectrum, and the moisture of the lubricating oil exceeds the standard or the acid value exceeds the standard.
4, surface strain: found in the iron spectrum cutting abrasive particles, abrasive particles are non-ferrous metals.
5, fretting wear behind the tile: spectral analysis found that the iron concentration is abnormal, there are many iron components in the iron spectrum sub-micron wear particles, lubricating oil moisture and acid value is abnormal.
Under liquid lubrication conditions, the sliding surface is separated by the lubricating oil without direct contact, and the friction loss and surface wear can be greatly reduced, and the oil film also has a certain vibration absorbing capability.
