Hallen Construction also constructs metering and regulating stations for National Grid, Con Edison, Williams Pipeline, Spectra Energy and Iroquois GTS. These stations consist of metering vaults or buildings, regulator buildings, heaters, and data and communication facilities. The main functions of these stations are to reduce the transmission pressure, heat the gas and meter the amount of gas flow.
Hallen’s role in the installation of these stations begins with site preparation, beginning with the excavations for the underground vaults and installing wood shoring. The precast concrete vaults are then delivered and offloaded into the excavations with a crane.
Some stations require buildings which house the piping components. If this is the case, Hallen will install the building foundations and then set the modular building. Whether the project requires buildings or below ground vaults, they are connected with welded steel pipe, communication ducts and control lines. All piping for these stations is welded steel, which must pass x-ray and air or hydro testing. Once the testing and drying is complete, the tie-ins are performed and the station is commissioned for service.