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  2. Reduced pressure zone device - Wikipedia

    en.wikipedia.org/wiki/Reduced_pressure_zone_device

    There is a variety of manufacturers of these gauges, but most utilize either a three-valve or a five-valve design to test the RPZD in different ways. In the UK , [ 6 ] Illinois, New York , [ 7 ] Texas , [ 8 ] and Missouri ( RsMO 10c60-11 ), the RPZD valve must be tested at least every 12 months by an accredited tester.

  3. Shutdown valve - Wikipedia

    en.wikipedia.org/wiki/Shutdown_valve

    A blowdown valve (BDV) is a type of shutdown valve designed to depressurize a pressure vessel by directing vapour to a flare, vent or blowdown stack in an emergency. BDVs fail-safe to the open position upon failure of the control system. [1] The type of valve, type of actuation and performance measurement are similar to an ESD valve.

  4. Blowout preventer - Wikipedia

    en.wikipedia.org/wiki/Blowout_preventer

    Pipe rams close around a drill pipe, restricting flow in the annulus (ring-shaped space between concentric objects) between the outside of the drill pipe and the wellbore, but do not obstruct flow within the drill pipe. Variable-bore pipe rams can accommodate tubing in a wider range of outside diameters than standard pipe rams, but typically ...

  5. Piping and instrumentation diagram - Wikipedia

    en.wikipedia.org/wiki/Piping_and_instrumentation...

    During the design stage, the diagram also provides the basis for the development of system control schemes, allowing for further safety and operational investigations, such as a Hazard and operability study (HAZOP). To do this, it is critical to demonstrate the physical sequence of equipment and systems, as well as how these systems connect.

  6. Relief valve - Wikipedia

    en.wikipedia.org/wiki/Relief_valve

    A relief valve DN25 on cooling water pipe from heat exchanger Schematic diagram of a conventional spring-loaded pressure relief valve. A relief valve or pressure relief valve (PRV) is a type of safety valve used to control or limit the pressure in a system; excessive pressure might otherwise build up and create a process upset, instrument or equipment failure, explosion, or fire.

  7. Piping and plumbing fitting - Wikipedia

    en.wikipedia.org/wiki/Piping_and_plumbing_fitting

    A threaded pipe has a screw thread at one or both ends for assembly. Steel pipe is often joined with threaded connections; tapered threads are cut into the end of the pipe, and sealant is applied in the form of thread-sealing compound or thread seal tape (also known as PTFE or Teflon tape) and the pipe is screwed into a threaded fitting with a ...

  8. Partial stroke testing - Wikipedia

    en.wikipedia.org/wiki/Partial_stroke_testing

    λ D = The dangerous failure rate of the safety function. TI FC = The full closure interval, i.e. how often the valve must be full closed for testing. TI PST = The partial stroke test interval. The proof test coverage is a measure of how effective the partial stroke test is and the higher the PTC the greater the effect of the test.

  9. Control valve - Wikipedia

    en.wikipedia.org/wiki/Control_valve

    A control valve is a valve used to control fluid flow by varying the size of the flow passage as directed by a signal from a controller. [1] This enables the direct control of flow rate and the consequential control of process quantities such as pressure, temperature, and liquid level.