Valves

Manual valve

Automated valve

Valves are required along the gas delivery system so that sections of the system can be isolated and shut down in the event of a leak or other emergency, or for controlling flow or performing maintenance. 

Valve applications include:

  • Mainline valves are used to shut off main flow stream.
  • Tap valves are used to shut off deliveries at offline delivery points.
  • Blowdown valves are used to release gas to de-energize a piping system.
  • Station valves are used to isolate compressor stations, pressure limiting stations, and metering stations.
  • Emergency valves are any valves used to isolate pipeline sections or a facility in an emergency.
  • MAOP valves are used to isolate sections of system where maximum allowable operating pressures (MAOPs) are different
  • Therm billing area (TBA) valves are used to isolate sections of system where gas Btu content is different.
  • Relief valves are used to release gas to atmosphere if pressure exceeds set point.
  • Excess flow valves are used to automatically close if excess flow is sensed.
  • Service valves are used to shut off flow of gas to customer at the meter.
  • Curb valves are valves in the street or sidewalk used to shut off services between the main and a customer meter (used when a service value at the meter might be inaccessible to a crew).

Most values are operated manually by a crew member, but some values are automated and may operate on their own given certain conditions or may be able to be operated remotely via electronic signal.


Up next …