Gas pressure reduction systems are needed in order to match the quality of the gas in the pipelines with the gas conditions required by the consumer. These specifications include the amount of gas flow, pressure and gas temperature which must be automatically controlled and recorded.
Pressure Reducing Stations:
City Gate Station (CGS)
CGS stations are stations that have been installed at the beginning of city entrances to reduce the gas pressure of the main and secondary transmission lines from high to medium pressure. Gas enters CGS stations through transmission pipelines with a pressure of 400-1000 psig. In CGS stations, in some cases, the pressure reaches a pressure of 250 psig in one step and in some cases, in two stages, first from 1000 psig pressure to 400 psig pressure and then from 400 psig pressure to 250 psig pressure.
Tower Border Station (TBS)
TBS stations are stations that are installed on the outskirts and inside cities to reduce the gas pressure of supply lines. In these stations, the gas first enters the station through the main lines of the power supply network or the belt loop with a maximum pressure of 250 psig. After reducing the gas pressure, it reaches a pressure of 60 psig and enters the distribution network lines, which are designed as rings and branches.
A combined station is a collection of two stations, CGS and TBS. Combined stations are used in stations and areas away from the city, where it is not economical to use both CGS and TBS stations.
Regulator Station (RS)
Most of the gas supply to special commercial consumers inside the cities is through network lines and by installing RS pressure reducing stations on site. The input pressure to RS stations is 60 psig and distribution will be based on consumption and pressure required for consumers.
Distribution Regulating Station (DRS)
DRS stations branch off from the urban power supply ring and are essentially a type of TBS station which are different in design. These stations are usually installed for specific areas.
Metering stations are stations that are installed solely to meter the amount of gas passing through. At metering stations, the volumetric flow rate of gas is metered without reducing the gas pressure. Metering stations are made in two types of flats and cabinets, which are cost-effective and useful in terms of space occupied by construction costs and sound control. The gas flow metering device is in two ways diaphragm and turbine, and in stations that use turbine flowmeter, the metering accuracy is less.