For a pipeline company to manage its gas pipeline system safely andefficiently, it must know how much gas is in the system at all times. This can be a daunting task, as pipeline systems often extend over thousands of miles. To accomplish this, pipeline companies use metering stations to measure all natural gas entering or exiting the pipeline system.
A meter station may use:
The metering facilities must provide accurate and continuous gas measurement.
Some meter stations also regulate gas pressure and delivery volumes and are called meter and regulator stations (M&R). Pressure regulation equipment ensures that gas delivered into or out of a pipeline system is maintained within a specified pressure range. This is important for safety reasons because engineers design transmission and distribution systems to operate within specific pressure ranges.
Pipeline companies install valves along a gas pipeline system to provide a means of controlling flow.
The valves may be spaced as close together as every five miles or as far apart as 20 miles according to standards established by applicable safety codes. The valves normally are open, but when a section of pipeline requires maintenance, operational engineers close the valves to isolate that section of the pipeline. Once isolated, the maintenance crew can vent the gas from that section of the pipeline and proceed with its work.