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Dixon Sanitary 2014
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Technical
R
a
log of the arithmetic mean of the surface profile.
RPM
Revolutions per minute
SPDT
Single pole double throw, a type of limit switch.
SPST
Single pole single throw, a type of limit switch.
STP
Standard conditions for temperature and pressure. In physical sciences, STP, are standard sets of conditions for
experimental measurements, to allow comparisons to be made between different sets of data. National Institute of Standard and
Technology's (NIST) version is a temperature of 20°C (293.15 K, 68°F) and an absolute pressure of 101.325 kPa (14.696 PSI,
1
atm).
Sanitary (hygienic) Weld
generally considered to be a groove weld in a square butt joint made by the GTAW (or
plasma) process as a fusion weld without the addition of filler material. A sanitary weld must be completely penetrated on the
weld ID, with little or no discoloration due to oxidation and be otherwise without defects that would interfere with maintenance in
a clean and sterile condition.
Santoprene
A thermoplastic elastomer, a rubber-like material that complies to FDA requirements.
Schedule
dimensional standard for pipe as defined by ASTM.
Seal Face
surface point on which a seal is achieved.
Service Temperature
The maximum and minimum temperature of the media.
Shut-Off Head
The maximum head that a pump can generate.
Silicon Carbide
Synthetic mineral of silicon and carbide. It is used in abrasives, refractories, ceramics and numerous high
performance applications.
Silicone
Dimethyl silicone, a synthetic rubber.
Sintering
Heat process in which powdered metal particles are heated to near melting point, fusing the metal granules together.
Specific Gravity
A measure of the weight of a liquid in relation to that of water. If the liquid in question will float on water
then the specific gravity will be less than one and if the liquid will sink when mixed with water the specific gravity will be greater
than one.
Spring-Return (SR) Pneumatic Actuator
Any pneumatic actuator which contains a single coil spring or group of
coil springs to oppose the movement of a piston or diaphragm. As air moves the piston or diaphragm the spring is compressed.
When the air supply is discontinued and exhausted, the spring extends and drives the piston or diaphragm in the opposite
direction. This type of actuator is normally used for applications where it is necessary for the valve to move to the open or close
position upon loss of air supply, whether by design or by system failure.
Static Discharge Head
The vertical distance in feet between the pump center line and the point of free discharge or the
surface of the liquid in the discharge tank.
Glossary of Terms
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