All necessary parts, tools, equipment and relevant data shall be prepared before installation. Also carefully Preparation Before Installation study the drawings or relevant instructions to determine the correct installation sequence of different components.
Carefully check the SKF Bearing Pedestal, shaft, seal and other parts in SKF Bearing configuration to ensure that the mating surface is clean and good. In addition, special inspection shall be carried out on screw holes, conduits or grooves to prevent some machining residues. For the cast SKF Bearing Pedestal, ensure that the coreless sand remains on some unmachined surfaces and remove all burrs.
Check the dimensional tolerance and shape tolerance of all components in SKF Bearing configuration. Relevant components must reach the required accuracy and meet the specified Preparation Before Installation tolerance range before SKF Bearing can play its due performance.
The diameter of cylindrical journal and seat hole is generally measured with micrometer or inner micrometer in Preparation Before Installation two cross sections and four different positions. The taper of journal can be measured by ring gauge, special taper gauge or sine gauge.
Relevant inspection and measurement results are recommended to be kept as records for reference when Preparation Before Installation necessary. During measurement, parts and measuring instruments shall be kept at approximately the same temperature to ensure the accuracy of measurement.
This means that it may be necessary to place the parts and measuring equipment in the same place for a considerable time to reach the same temperature. This is particularly Preparation Before Installation important for large SKF bearings and their related components.
In general, there is no need to remove the antirust agent coated on SKF Bearing before leaving the factory, just wipe the outer circle and inner hole of SKF Bearing. However, if SKF bearings are lubricated with grease and applied at very high or low temperatures, or all greases are incompatible with antirust agents, it is necessary to clean SKF bearings and dry them carefully before installation to avoid damaging the effect of grease.
If the SKF Bearing may be contaminated due to improper Preparation Before Installation treatment, it is also necessary to clean and dry the SKF Bearing before installation.
If the antirust agent on the surface of SKF Bearing removed from the original package is relatively thick or has high viscosity, it is also necessary to clean and dry the SKF Bearing. This may happen to some oversized SKF bearings with an outer diameter Preparation Before Installation greater than 420mm. In this case, petroleum solvent or paraffin can be used to remove the preservative on SKF bearings.
If SKF Bearing with sealing ring or dust cover is used, it cannot be cleaned before installation because it has been filled with grease at the Preparation Before Installation factory. The tapered hole bearing can be directly installed on the tapered journal, or it can be installed on the cylindrical journal with the tightening sleeve and disassembly sleeve as the intermediary.
The reduction of radial clearance is the difference between the radial clearance of SKF Bearing before and after installation. The original radial clearance of SKF Bearing shall be Preparation Before Installation measured before installation, and the clearance shall be measured frequently during installation until the radial clearance reduction corresponding to the ideal interference is achieved
The measurement of radial clearance reduction can also be replaced by the measurement of the propulsion of SKF Bearing on conical journal. For the standard taper of 1:12, the reduction of radial clearance is about 1 / 15 of the axial thrust. In this proportion, for the solid shaft, the interference of the mating surface is only 75% ~ 85%, which plays a role in expanding the inner ring.
The reduction of radial clearance of large spherical roller SKF Bearing and cylindrical roller bearing is usually measured with feeler gauge. Note that for spherical roller SKF Bearing, the radial clearance at the two rows of rollers must be measured from the two end faces respectively. Only when the clearance value at the two rows of rollers is the same, can the inner ring and outer ring be relatively positive.
The small tapered hole SKF Bearing cannot be measured with a feeler gauge because its radial clearance is too small. A dial indicator can be used to contact the shaft or SKF bearing seat to measure the lifting amount during propulsion.
At this time, attention is paid to the change of radial clearance, and the elastic deformation of rolling element and raceway is not considered. The force used to push SKF Bearing or bearing seat should be roughly equivalent to their weight.