Overview of Industrial Pressure Gauges

PRESSURE GAUGE OVERVIEW Pressure gauges are instruments designed to measure the pressure in a most direct way. Measuring the pressure in your system is a critical quality step to ensure consistency of a product and they provide an easy way to see pressure at a glance. The correct pressure gauge can be determined based on selection criteria, to accurately measure the pressure within the system.

Even the best measuring equipment produces a certain deviation from the actual value. It is important to know how this measurement accuracy is defined. Digital gauges in comparison with analog ones have higher accuracy. Read our article on digital pressure gauges if you want to learn more about that type.

Basics of Pressure & Pressure Measurement Pressure is defined as the amount of force applied perpendicular to a surface of object per unit area. In a steady liquid or gas, this is the amount of force applied to the wall of the carrier medium at a given point.

Static pressure is uniform in all directions. However, a moving fluid applies additional pressure in the direction of the fluid flow while having small impact on the surfaces parallel to the flow direction. This additional pressure is called dynamic pressure. The total pressure of a flow is the sum of static and dynamic pressure in that flow.

If a device is incorporating the flow direction, it measures or counts the total pressure of the flow.

Instruments mentioned here are designed to measure static pressure in a system.

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Pressure is often measured in three forms: 

Absolute Pressure represents the total amount of force per unit area. A perfect vacuum has an absolute pressure of zero while earth’s atmosphere at sea level has an absolute pressure of 1 atm.

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Gauge Pressure is what most pressure gauges indicate, which is the pressure of the media relative to the atmospheric pressure. If a pressure gauge is designed to measure pressures less than atmospheric pressure (known as vacuum pressure), they may be labelled as “vacuum gauge” and the negative may be omitted. To signify that a pressure measurement is relative to the atmospheric pressure, the letter “g” follows the unit pressure.

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Differential Pressure is simply the pressure difference between two given points. Some gauges offer this measurement to provide convenience by eliminating the need to subtract two pressure readings in a system.

Types of Pressure Gauges According to Usage 1. Industrial Pressure Gauges – Industrial pressure gauges are general purpose pressure measuring devices commonly used in Heating Ventilation Air Conditioning (HVAC) and Refrigeration. It is best suitable for production processes that would not block the pressure system. Commercial or Industrial gauges are used in manufacturing industries, hydraulic, water treatment and OEM applications.

2. High Precision Test Gauges – Test gauges are demands for processes that require high degree of accuracy and precise calibration as in testing laboratories.

3. Low Pressure Gauges – These are well-suited for measurement of liquid and gaseous pressure, provided they don’t halt its functioning. Plants construction processes, factory pneumatic systems and engine rooms often need low pressure gauges.

4. Seal Gauges – These gauges are well demanded for sealing hazardous leak paths and are used in variety of industrial applications to meet material compatibility requirements, corrosive chemicals, viscous applications, sanitary and pharmaceutical requirements.

5. Process Pressure Gauges – In industries where the production process functions under high mobility conditions, subjected to vibrations, periodic perturbation, Wear and tear environment (like in certain areas of maritime and other petrochemical industries), a process pressure gauge can be safely used without damage.

6. Duplex Pressure Gauges – These are differential pressure gauge that can function like a comparator in extreme environments and measure the difference between two applied pressures.

This is sometimes required in air-handling, refrigeration, chemical and fuel Industries.

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Choosing the Right Pressure Gauge To select a proper pressure gauge, consider the factors like the level of accuracy required, suitable dial size for readability, durability of material to suite environment and the gauge process, range, environmental considerations, mounting requirements and pressure type to be measured etc.

Determine what kind of gauge may be right for you to use, all of which can affect gauge performance. If you choose a manufacturer who gives you a wide variety of gauges to choose from, choosing the right one will be an uncomplicated process.

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