What item is not commonly used when piping up a reducing station?

A thermometer is not commonly used in a reducing station setup. Reducing stations are primarily responsible for controlling pressure and typically include components such as pressure gauges, flow meters, and shut-off valves to monitor and manage the flow and pressure of the fluid being transported.

The pressure gauge is essential for checking the inlet and outlet pressure to ensure that the system operates within safe parameters. A flow meter is used to measure the volume of the fluid passing through the system, providing crucial data for monitoring system efficiency and effectiveness. The shut-off valve is key for controlling the flow of the fluid and ensuring safety during maintenance or in emergencies.

In contrast, while temperature can be an important factor in many systems, it is not a primary concern for the operation of a reducing station. Thus, a thermometer is less commonly integrated into this particular setup compared to the other listed items, which are directly related to pressure and flow management.