Gas Pressure Gauge
A gas pressure gauge is an instrument designed to measure and display the pressure of a gas. Pressure gauges assess the pressure of fuel, oil, water, air, and vacuums and indicate the results on a screen or on a dial. Display types include graphical and video displays, digital readouts, or analog meters and needles.
Gas pressure gauges indicate the internal pressure of whole systems or individual vessels and are essential for applications where the accurate function of a system or vessel depends directly on the correct pressure as determined through gauges.
Quick links to Gas Pressure Gauge Information
Components of Gas Pressure Gauges
Materials
Gas pressure gauges are constructed of:
- Stainless Steel
- Bronze
- Brass
- Aluminum
Internal Components
The internal components are held inside a metal housing, and the viewing window is made from double-strength glass. Some gauges require rubber or plastic seals, plugs, or rods.
Applications and Design of Gas Pressure Gauges
Pressure gauges are a type of sensor and are usually combined with other instruments or devices such as shutoff valves, couplings, or fittings. Pressure gauges can also be equipped with electric contacts to turn on signal lights and sound alarms or operate a pump or valve. In this case, they are called pressure transducers.
Gas pressure gauges vary in style, size, and material, depending on the application. They are widely used by manufacturing plants or industrial companies where it is important to monitor any changes in pressure in order to control the rate of flow of gases such as propane or natural gas.
Types of Gauges
- Hydrostatic Gauges
- Use liquid to compare pressure to the pressure exerted by the force of gravity on a fluid at equilibrium. These measurements are independent of the type of gas that is being measured, and they have a poor dynamic response, so they are not generally used for gas.
- Aneroid Gauges
- The majority of gas pressure gauges are aneroid. Aneroid pressure gauges use a flexible metal membrane that bends, curls, or twists according to the pressure being exerted. Aneroid gauges are able to evaluate both liquid and gas pressure and do not need to use any liquid to do so.
Within this category are Bourdon tubes and diaphragm gauges, both of which use bellows.
- A C-shaped or coiled tube in the Bourdon gauge is connected to the system or vessel where the pressure must be read.
- The tubes coil and uncoil depending on a decrease or increase in pressure.
- A diaphragm gauge uses a membrane sealed in between two regions of varying pressure.
- The membrane flexes or deflects, and the deformation is measured as the pressure.
- Even the slightest bend in the bellows or membrane is detected by the pressure sensing element and transmitted to the display.