HSF fabric-reinforced seals
The spring-loaded HSF seal assortment consists of the HSF5, HSF6, HSF7 and HSF8 solid seals and their split versions, HSF1 (fig 1), HSF2 (fig 2), HSF3 (fig 3) and HSF4 seals. There is also a pressure profile seal, HSF9, available in the solid version only. These seals are mainly used in heavy-duty applications like gear drives, propeller shafts, cold and hot mill work rolls, pumps, paper machinery, etc.
HSF5, HSF6 and HSF7 seals have a strong, flexible, fabric-reinforced rubber back instead of a metal case. HSF5 seals have a basic single-lip design. HSF6 seals are equipped with radial lubrication grooves in the back of the seal and HSF7 seals include a circumferential lubrication groove. HSF4 and HSF8 seals are designed with an auxiliary lip for additional protection against contaminants.
Threaded spring connections are standard for all HSF seals (fig 4). For the split versions, a hook-and-eye connection can also be specified (fig 5).
All HSF seals are manufactured oversized relative to the housing bore diameter and depth to enable proper compression and stability. A cover plate (fig 6 and fig 7) is required to properly install and apply all HSF seals. The plate creates an axial preload to provide reliable static sealing performance. The plate should also avoid seal distortion during installation. HSF seals are available in nitrile rubber, hydrogenated nitrile rubber and fluoro rubber materials.
A selection of available HSF seal sizes is listed in the product table. Contact your SKF sales representative for additional information regarding availability.