|
Glossary of Shaft Seal Terms:
A B C D E F G H I J K L M N O P Q R S T U V W X Y Z |
Bonded Seal: Design feature of a type of radial lip seal. The heel of the sealing element is attached (Bonded) to the seal case by and adhesive during the molding o peration.
Bore, Housing: (Bore, Seal) A cylindrical surface which mates with the outside surface of the seal outer case.
|
Case, Inner: (Shell, Inner) A rigid, cup-shaped component of a seal assembly, which is placed inside the outer seal case. It can function as: reinforcing member, shield, spring retainer, lip-clamping device.
Case, Outer: (Shell, Outer) The outer, cup-shaped, rigid structure of the lip seal assembly. Acts as a protective cover for the head of the sealing
element.
|
Dynamic Seal: A seal which has rotating, oscillating, or reciprocating motion acting upon it.
Durometer: An instrument which measures with an indentor point the hardness of rubber by penetration, without puncturing the
surface of the rubber.
|
Elastomer: An elastic rubber like substance, such as natural or synthetic rubber.
|
F.P.M.: Feet Per Minute; used as a measure of shaft speed instead of R.P.M.
To convert R.P.M into F.P.M., use formula .262 x R.P.M. x diameter (inches) = F.P.M.
Fluid Side: Side of the seal which in normal use faces toward the fluid being sealed.
|
Garter Spring: Coiled wire spring with its ends connected. It is used for maintaining a sealing force between the sealing element and a
sealing surface.
|
|
Machine Lead: Spiral grooves similar to a screw thread on a shaft surface that can result from improper finishing process; may result in early leakage.
|
Primary Lip: The flexible elastomeric component of a lip seal, which contacts the rotating surface.
|
RA: The average of all peaks and valleys from the mean line within cut-off (.010” of .254mm). Ra does not describe the surface profile (texture) and two shafts with the same Ra value can have very different surface characteristic.
RPM: Revolutions per minute.
Run-In: The period of initial operation during which the seal-lip wear rate is greatest and the contact surface is developed.
Run-0ut: That run-out to which the seal lip is subjected due to the outside diameter of the shaft not rotating in a true circle. Usually expressed as T.I.R. (Total Indicator Reading).
RZ (din): Average peak to valley height
Scoring: A type of wear in which is generally defined by the inside and outside lip surfaces and the spring groove.
|
Seal, Heel Section: The portion of the lip seal which is attached to the seal case.
Seal, Outside Diameter: The external diameter of a lip seal assembly. Usually the outside diameter of the outer seal case.
Seal Width: The over-all axial dimension of the lip-seal assembly. Normally the total width measurement of the outer seal case.
Sealing Element: The normally flexible elastomeric component of a lip-seal assembly which rides against the shaft.
Secondary Lip: A short, non-spring loaded lip, which is located at the outside seal face of a radial lip seal. Used to exclude contaminants.
Shaft Diameter: The outside diameter of the shaft at the location where the seal is mounted.
Shaft Finish: The relative roughness, usually expressed in micro inches, of the outside diameter of the shaft. The smaller the number, the smoother the finish.
Shaft Seal: Generally considered to be a lip seal or an oil seal, but a broad definition could include and sealing device mounted on a shaft or sealing a shaft.
Sleeve, Wear: A replaceable metal ring. Generally used in assemblies to eliminate expensive shaft replacement caused by grooving that may occur at the seal-shaft interface.
S.T.B.M. Shaft-to-Bore-Misalignment, the amount by which the shaft is off centre, with respect to the bore’s centre.
|
|
|
 |
|
Technical Resources
|
|
