Shaft seal design is never complete without giving due consideration to the shaft on which the seal will be asked to function. There are several important shaft-related factors that determine a sealing lip’s ability to establish and maintain a proper dynamic seal with the shaft.

These include the shaft material, surface finish, hardness, diameter, chamfer, and tolerances. Also critical are the shaft’s motion (rotating, reciprocating, or oscillating) and speed, as well as the amount of eccentricity (shaft-to-bore misalignment and/or dynamic run-out) present.

MATERIAL
SURFACE FINISH SPECIFICATIONS
SURFACE FINISHING METHODS
HARDNESS
DIAMETER
CHAMFER
TOLERANCES
MOTION
ECCENTRICITY