The following procedure can be used to install stepped sleeves. If stepped sleeves are to be installed against bearings that are already greased, care should be taken that the injected oil / mounting fluid does not mix with the grease and impair its lubricating properties.
- Heat the sleeve to obtain the required temperature difference listed in table 1 and table 2.
- Push the sleeve onto the shaft seat.
- After the sleeve has cooled, inject oil or an SKF mounting fluid between the sleeve and shaft using suitable oil injection equipment (fig. 1 and Oil injection equipment and pressure media). To avoid local stress peaks, the oil should be injected slowly and the oil pressure regulated.
- Use a hydraulic nut and suitable distance sleeve to bring the sleeve to its final position (fig. 1). When using a hydraulic nut, the force of the nut against the bearing arrangement can be controlled by the oil pressure. As the sleeve “floats” on the oil film, any stresses produced during the shrinking of the sleeve (produced as the sleeve cooled) are relieved and the components can be correctly positioned relative to each other. When the required axial force has been obtained, the final position is reached.
- With the tool still in position, release the oil pressure between the mating surfaces and allow the oil to drain. Normally it takes about 24 hours before the sleeve can support its full load.