GLOSSARY OF VALVE TERMS
NORMALLY OPEN SOLENOID VALVE An electrically operated valve whose inlet orifice is open when the solenoid coil is not energized. Energize to close. See Solenoid (Section 2). NPS (Nominal Pipe Size) Numerical inches designation of size which is common to components in piping systems of any one size. The nominal pipe size is designated by the letters NPS followed by a number. See also National Pipe Thread and API 6D / ISO 14313. OD (Outside Diameter) The measurement of the outermost diameter of a circular part. OPERATOR A device which conver ts manual, hydraulic, pneumatic or electrical energy into mechanical motion to open and close a valve.
Hydraulic Actuator
OPERATING TEMPERATURE A media temperature that the valve is operating in and will be required to be opened or closed at any time in this temperature range. OPERATING TIME The time required for a power operator to stroke the valve from the full open to full closed position or vice versa. O-RING An elastomeric or synthetic seal ring of circular cross section.
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