1) A step in the production of braided packing where a braided material is fed through rollers to squeeze it to its finished size. 2) A machine which is used to calender a braid.

The reduction of a material to carbon.

A coating applied to the case OD to prevent leakage between the seal case and the housing bore.

An undesirable phenomenon that sometimes occurs in pumps, in which small vapor bubbles are created in the area of the impeller. As these vapor bubbles move along the vanes of the impeller to an area of higher pressure, they rapidly collapse. This collapse or "implosion" is so rapid that it may be heard as a rumbling noise or felt as vibration. The forces generated as a result of cavitation may damage the impeller or even the packing set.

A solid piece of metal used on the OD of a gasket winding in order to center the gasket properly on the sealing surface by locating the ring against the studs in the connection. The ring also acts as a compression limiter to prevent overcompression of the winding.

A type of pump which relies on the rotation of an impeller to generate pressure and cause flow.

The short, shallow cracks on the surface of a rubber product resulting from damaging action or environmental conditions.

Also known as Vee Packing and Stack Packing, an automatic Hydraulic and Pneumatic seal designed for sealing rods, rams, pistons, and plungers. Consisting of a male and female adapter and at least (3) CHEVRON "vee" rings which utilize a distinct hinge area to allow automatic reaction to pressure. CHEVRON-type packing are lip-type seals and are gland sensitive.

Surface roughness of a shaft measured in a direction (plane) normal to the centerline axis.

Same as back-up bars.

Rubber sheet consisting of a ply of fabric or cloth on each surface. CDS: Cloth on just one side.

Rubber sheet containing one or more plies of fabric or cloth, in which the fabric is completely covered with rubber.

An installation in which the plane of the outside seal face is not perpendicular to the shaft axis.

One turn of the coiled wire garter spring.

Gasket for the coke unit in petroleum refineries.

Permanent and continual deformation of a material that occurs as a result of prolonged compression or extension at or near room temperature.

The height of a packing ring or packing set after it has been compressed in the stuffing box.

A gasketing material primarily containing fibers, rubber and fillers, manufactured on a special calender (known as a "sheeter") in such a manner that the compound is caused to build up under high load as an oriented sheet on one roll of the sheeter.

The quality or state of being compressible. In the case of gasketing, it is the percent loss of thickness when subject to a given load.

Ring used in conjunction with a seal to control or limit compression of the seal.

A deformable material used to prevent or control the passage of a pressurized fluid between surfaces that move in relation to each other.

The deformation that remains in the gasketing after it has been subjected to, and released from, a specific compressive stress for a definite period of time at a prescribed temperature (Compression Set measurements are for the purpose of evaluating creep and stress relaxation properties of elastomeric constructions.).

Force per unit area compressing (squeezing) the seal.

A common vacuum industry flange.

Synonym: Angle, Outside Lip.

The line of intersection between the outside and inside lip surfaces of a radial lip seal. In a cross-sectional view, this intersection is illustrated as a point.

The axial distance from the outside seal face to the lip contact line.

The width of the lip contact area of a radial lip seal, measure in the axial direction.

Actual operating temperature of service.

Molded, formed, or radius belt corners of rectangular/square expansion joint.

An ingredient added to packing, which decreases or eliminates the possibility of galvanic corrosion in the stuffing box. Corrosion inhibitors may be classified as either passive or active. See "Active Inhibitor", "Passive Inhibitor", and "Galvanic Corrosion".

Formed into alternating peaks and valleys; typically limited to sheet metal 0.024" and thinner.

The outermost ply of material of an elastomeric expansion joint.

A sharp break or fissure in the sealing element.

A sharp break or fissure in the surface, generally due to excessive strain.

A transient stress-strain condition in which strain increases concurrently with the decay of stress. More simply put, it is the loss of tightness in a gasket, measurable by torque loss.

Of or relating to a very low temperature.

The shape of certain types of die-formed ring sets. In a "cup and cone" set the rings have conical surfaces that nest into one another.

A specific type of hydraulic or pneumatic sealing element which seals primarily on it’s outside diameter.

The act of vulcanization. (Also see Vulcanization)

A deep discontinuity in the seal material whereby no material is removed.

A braided material cut into individual rings for a specific stem/stuffing box size and packaged as a set.

A procedure used to consolidate a packing set after it has been installed in a stuffing box. This procedure helps to reduce the amount of gland load relaxation that occurs after the valve has been put into service.

A device which converts fluid power into linear mechanical force and motion. It usually consists of a moveable element such as a piston and piston rod, plunger rod, plunger, or ram, operating within a cylindrical bore.

The internal diameter of the cylinder.

A cylinder with a piston rod extending from each end.

A cylinder with a piston rod extending from one end.

A cylinder in which the piston and piston rod are one and the same. These cylinders are single-acting and are mounted vertically: the weight of the load retracts the cylinder.