A pressure gauge cock (also known as a stopcock) is an adjustable overpressure safety device used to protect your plumbing system against pressures that exceed the range of the pressure gauge.
How a pressure gauge cock works
As safety devices, pressure gauge cocks serve several functions. In addition to protecting the system against pressure, they can isolate the pressure gauge from the pressure medium and extend the service life of the pressure gauge when the gauge endures continually pulsating pressure.
Types of pressure gauge cocks
Pressure gauge cocks are differentiated by their connection genders (the connections on either side may be exclusively male or female, or both). When examining the types of threads and connections available, you will notice several different abbreviations. BSP indicates that the thread has been made according to the British Standard Pipe family of technical standards. The letter G denotes a parallel thread (or straight thread) with a constant diameter, also referred to as a British Standard Pipe Parallel thread. The body of a pressure gauge cock is typically made from brass, steel or stainless steel .