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Dixon Sanitary 2016
800.789.1718
Technical
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Glossary of Terms
Compression Set
The deformation that remains in rubber or PTFE after it has been subjected to and released from stress
such as a clamp. The longer the stress is maintained the more definitive the deformation.
Durometer
An instrument for measuring the hardness of rubber by resistance to penetration
Durometer Hardness
A numerical value which indicates the resistance to indentation of the blunt indentor of the
durometer.
EPDM
Ethylene propylene diene monome, a synthetic rubber
Elastomer
Any of various elastic substances resembling rubber.
Electropolishing
A controlled electrochemical process utilizing acid electrolyte, DC current, anode and cathode to smooth
the surface by removal of metal.
Encapsulation
The enclosing of material by an encapsulant for protective purposes. In a ball valve the ball is encased in
PTFE, preventing the material flowing through the valve from getting behind the ball causing contamination
problems.
Flow Coefficient (C
v
)
C
v
the flow rate in U.S. gallons of water (at 60°F) that will pass through the valve in one minute with
a differential pressure across the valve of 1 PSI.
Ferrule
A bushing used to secure a tube joint. A special bushing designed for welding to the end of tubing. Two ferrules and a
gasket make a leak-proof connection when used with the complimentary clamps.
Fitting
A small part of an apparatus (may be detachable).
Fluorocarbon
Synthetic rubber and fluoropolymer elastomer known as FKM.
Friction Loss
The part of the total loss that occurs as the fluid flows through straight pipe.
Hex Union Nut
An internally acme-threaded six-sided connector used to assemble bevel seat fittings.
ISO5211
International standard for actuator and valve interface
Internal Expansion (IX)
A plug (or bullet) is pulled through a stem or a set of blades (fingers) increase the stem ID to
the plug OD or a predetermined setting when using expansion blades (fingers). This forces the
stem serrations into the hose tube and the hose cover into the serrations of the ferrule.
Laminar Flow
The smooth flow of a viscous liquid through a tube or pipe. In that case, the velocity of flow varies from zero
at the walls to a maximum along the centerline of the vessel.
Maximum-Shut-Off Pressure
The pressure of the media flowing into the valve against which the valve will have to
close.
Media
The material flowing through the valve.
Modulating Service
Proportional positioning of a valve between the open and closed position. Used for flow control
processes.