G design radial shaft seals
G design radial shaft seals are made of acrylonitrile-butadiene rubber (NBR). The seals for shaft diameters ≥ 8 mm (fig 1) are reinforced with sheet steel. The rubber outside diameter enhances the seal around the housing bore and reduces the risk of damage to the seal and housing during installation and removal.
To attain an adequate degree of rigidity for seals for shaft diameters ≤ 7 mm (fig 2), the rubber material is metal cased. These seals are identified by the designation suffix S.
If the seal is to be used primarily for lubricant retention it should be mounted with the lip facing inward. If the primary purpose of the seal is to exclude contaminants, the lip should face outward, away from the bearing (fig 3).
For information about the chemical resistance of acrylonitrile-butadiene rubber (NBR), refer to the section Chemical resistance.