Design considerations

Abutment dimensions

The abutment dimensions da min and Da max listed in the product table apply for axial bearing loads Fa ≤ 0,1 C0.

For heavier bearing loads, it may be necessary to support the shaft and housing washers over their entire side faces (da = d1 and Da = D1).

For heavy loads, where P > 0,1 C0, the shaft washer bore must be fully supported by the shaft, preferably by an interference fit. Even the housing washer should be radially supported (fig. 1).

For additional information about dimensioning washer supports, contact the SKF application engineering service.

Recessed housing bore for bearings with a stamped steel cage

For bearings fitted with a stamped steel window-type cage, the housing bore must be recessed (fig. 2) to prevent the cage from contacting the housing during possible misalignment. SKF recommends the following guideline values for the recess diameter:
  • D + 15 mm for bearings with an outside diameter D ≤ 380 mm
  • D + 20 mm for bearings with an outside diameter D > 380 mm

Axial clearance in bearing arrangements

SKF spherical roller thrust bearings in face-to-face or back-to-back arrangements should be preloaded. However, at the relatively low speeds shown within the green area in diagram 1, the application can be designed to operate with a small axial clearance. For these applications, bearings with a modified shaft washer (designation suffix VU029) should be used. Small axial clearance enables simple and cost-effective bearing arrangements to be used, e.g. for horizontal shaft applications at relatively low speeds, as no external preload is necessary.

For additional information about bearing arrangements with axial clearance, contact the SKF application engineering service.

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