ID
Abbreviation for "Inside Diameter". Used when denoting the inside dimension of a packing set, usually equal to the stem or shaft diameter.
IMPELLER
The part of a centrifugal pump that, when rotated, will generate pressure and cause flow.
IMPRESSION
During vulcanization, the design formed in the surface of any rubber article by a method of transfer. See "Fabric Finish."
INCLUSION
Foreign matter included in the seal material.
INNER CASE
A rigid, cup-shaped component of a seal assembly, which is placed inside the outer seal case. It has one or more of the following functions: reinforcing member, shield, spring retainer, lip-clamping device.
INNER PLY
The inside ply of a multiple-layered joint.
INNER RING
A solid ring used on the ID of a spiral wound gasket in higher pressure applications. This ring also acts as a compression limiter and provides protection from the media stream.
INSIDE FACE
That surface of the inner case which faces, and is usually in contact with, the fluid being sealed.
INSIDE LIP ANGLE
The angle between the inside lip surface and the axis of the seal case.
INSTALLED FACE-TO-FACE DISTANCE
The distance between the expansion joint flanges after installation when the system is in the cold (off) position.
INTEGRALLY FLANGED TYPE EXPANSION JOINT
An expansion joint in which the joint flanges are made of the same material as the body of the joint, as in ÒUÓ type joints.
INTERNAL ARCH CORNER
An expansion joint corner with the arch formed inwardly that is designed primarily for vacuum service. Generally used in conjunction with a rectangular or square expansion joint.
INTERNAL PRESSURE
Pressure (Lbs/Sq. Inch) exerted on the ID of a seal.
ISO
Abbreviation for International Standards Organization.