Pressure gauges are used for a variety of industrial and application-specific pressure monitoring applications. Uses include visual monitoring of air and gas pressure for compressors, vacuum equipment, process lines and speciality tank applications such as medical gas cylinders and fire extinguishers. In addition to visual indication, some pressure gauges are configured to provide electrical output of indicated pressure and monitoring of other variables such as temperature.
It is important to select a pressure range that accommodates all anticipated pressure swings, and which prevents excessive needle movement. It is recommended to confine normal operating pressure to 25% to 75% of scale. With fluctuating pressure (e.g., pulsation by a pump or compressor) the maximum operating pressure should be lower (50% of the full range).
Choices for pressure gauges measurement ranges include positive pressure, vacuum measurement, compound measurement, differential pressure, absolute pressure, and sealed pressure.
Level gauges are industrial meters used to determine the level of a liquid in a fixed storage or process tank. Liquid level gauge calibration is used to ensure proper readings are obtained when using level gauges.
There are several basic types of level gauges. Examples include
A magnetic level gauge is used to control the level of fluids. A tank level gauge is used in tank volume monitoring. A fuel level gauge provides a direct fuel level reading for vehicle and equipment. A water level gauge is used for measuring the rise and fall of water levels. A mechanical level gauge monitors levels of underground storage tanks. Other level gauges are also commonly available.
Vacuum gauges are devices for measuring vacuum or sub-atmospheric pressures. They use several different technologies. Manometers are usually made of a transparent U-shaped tube and partially filled with a liquid such as water, mercury or oil.
Thermocouple gauges measure changes in the thermal conductivity of a residual gas within a gauge tube.
Hot cathode ionisation gauges initiate a constant electron flow from the cathode or electron source to the anode or electron drain. Cold cathode ionisation gauges are also available.
Selecting vacuum gauges requires an analysis of display types, scale types and scale units. Some devices include analog or digital meters. Others include a cathode ray tube (CRT), liquid crystal display (LCD), or other multi-line video display. Single scale devices display pressure in only one set of units. By contrast, dual scales devices display pressure in two sets of units on the same dial face. There are many scale units for vacuum gauges. Examples include pounds per square inch (psi), kilo pascals (kPa), atmospheres (atm), bars, inches of mercury (inHg), centimetres of mercury (cmHg), inches of water (inH2O), feet of water (ftH2O), kilogrammes per square centimetres (kg / cm2), and ounces per square inch (oz / in2).
We supply filters and gauges in the UK. For any enquiries on gauges, no matter the type or application, contact Universal Supplies (Clydesdale) Ltd.