The vacuum pressure gauge is used to measure the pressure that is less than atmos. It is widely used in gas transportation, pipeline liquid and closed container to measure the pressure of the various liquid, gas, steam and other media.
The vacuum pressure gauge helps to determine the total dynamic head (TDH) on the system and with the pressure gauge reading will give an accurate TDH that can be used with the pump curve to determine pumps flow capacity.
This vacuum gauge contains a hermetically sealed, evacuated, thin-walled diaphragm capsule which is located within the instrument. As the vacuum pressure reduces, the capsule bulges. This movement is transferred via a system of levers to a pointer and can then be read off as the pressure on a linear scale.