Multiple HS seal installations

When installing two split all-rubber HS seals in one cavity, the locations of the split joints should be staggered by 30° to 60° to minimize the risk of leakage through the joints. The splits should be located toward the top of the bore. Grease the cavity between the seals to provide lubricant to the outer sealing lip.
When two HS seals, split or solid, are installed in the same housing bore, a spacing washer must be placed between the two seals (fig 1). Suitable washer dimensions can be determined based on the shaft and housing bore diameters, d1 and D, respectively:

washer inside diameter = d1 + 6 to 10 mm (0.25 to 0.4 in.)
washer outside diameter = D – 0,5 to 1,5 mm (0.02 to 0.06 in.)
The width of the washer is determined by the application conditions. There should, however, always be sufficient room for lubrication holes to be provided in the circumference, or lubrication grooves in one side face (fig 2). These lubrication provisions must enable grease to be supplied from the housing to the sealing lips via a drilled passage or grease fitting (fig 3). When determining what washer width is appropriate for the depth of a housing bore, it is necessary to consider the axial displacement required when clamping the seals.
SKF logo