Knowledge of installation of precision bearings
1. Requirements of precision bearings for matching parts
Since the precision of the precision bearing itself is less than 1μm, it needs to have high dimensional accuracy and shape accuracy with its supporting components (shaft, bearing housing, end cover, retaining ring, etc.), especially the accuracy of the mating surface should be controlled to be the same as the bearing This level is crucial and the most easily overlooked.
It must also be noted that if the matching mechanical precision bearings do not meet the above requirements, the error often appears several times or even more than 10 times after the original incorrect installation of the SAIQ bearing precision bearing. It is completely a precision bearing, machine, because the wrong matching component is usually The error is not simply superimposed on the bearing, but is different from the amplification factor after the addition.
2. Coordination of precision bearings
In order to ensure that the bearing does not cause excessive deformation after installation, it must strive to:
(1) The roundness shaft and the housing have appropriate accuracy holes and collars according to the requirements of the vertical bearing.
(2) It is necessary to accurately analyze and calculate the interference amount of the rotating ferrule fit, and also calculate the appropriate fit amount of the fixed ferrule of the enterprise through accurate data.
It is also advisable to obtain a small amount of combustion disturbance within the possible range.. long, and to ensure the thermal expansion at the operating temperature and the effect of the centrifugal force at maximum speed, so as not to cause creeping tight fit or sliding surfaces. The fixed ferrule selects a very small clearance fit or interference fit according to the working load of the enterprise's working environment and the bearing size. Too loose or too tight are not conducive to students to maintain their original accurate shape.
(3) Because the SAIQ bearing is running at high speed and higher operating temperature, and pay special attention not to turn the collar too loose to prevent the occurrence of eccentricity, and a gap is not fixed to the collar, the collar is at The sequence prevents load and deformation vibration excitation.
(4) The condition for the small interference fit of the fixing ring is that the matching surface is carried out. Both companies have high requirements for different shapes and precision and small roughness, otherwise it will cause some difficulties in system installation and disassembly is more difficult. In addition, We need to consider the effect of thermal elongation of the spindle.
(5) The axial preload of a pair of SAIQ double angular contact ball bearings is much greater. If the combined interference is too large, it will cause adverse effects. Double-row cylindrical roller bearings, tapered roller bearing mandrels and a main shaft, the load is relatively large, so that the interference fit is also relatively large.