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Manometer vs Pressure Gauge: Key Differences

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Pressure measurement is the measure of the force applied by a gas or liquid on a surface. Pressure measurement is an essential measurement in continuous process industries. Usually, manometers and pressure gauges are used for the measurement of pressure. Many technicians usually get confused while choosing their instrument for pressure measurement. That's why we're here to discuss the comparison between a manometer vs pressure gauge. 

What is a Pressure Gauge?

A pressure gauge is an instrument used to measure the intensity of a fluid. Pressure gauges are involved in the tuning and building fluid power mechanics and are essential in the troubleshooting process. You can install them anywhere in the machine where you need to keep an eye on pressure variations. 

The most commonly used types of pressure gauges are the diaphragm, Bellow, and Bourdon tube, out of which the Bourdon pressure gauge is most important.

What is a Manometer?

A Manometer is an instrument used to measure the pressure of a fluid by balancing and creating a hydraulic pressure against a predetermined column of fluid. A manometer will also help you to measure comparatively high and negative pressure. 

The most commonly used manometers are the U-tube manometer, small manometer, inclined manometer, and well tube manometer. 

Manometer vs Pressure Gauge – Working Principles

To understand the significant differences between manometer and pressure gauge, you need to learn about the working principle of both. There are many points to answer how the pressure gauges are different from manometers.

Working Principle of Manometers

The working principle of the manometer is very simple. It says that the pressure at any point of a liquid in a tube is the same when it is at a rest state, called hydrostatic equilibrium. For example, the pressure level of liquid on the right-hand side is equal to the pressure level of liquid on the left-hand side. 

Now, if you open one end of the tube, which is connected to some additional tube, this will create a different pressure on the open end of the tube. So, suppose the pressure of an additionally connected tube is greater than the atmospheric pressure. In that case, it will create downward pressure on the measuring liquid, which results in pushing down the liquid with more significant pressure and raising the liquid on the other hand side. 

The opposite will occur when the pressure in the additionally connected tube is less than the atmospheric pressure. Ultimately you will notice the liquid would go down on the open section of the U-tube and rise on the other side, connected to the additional tube.

Working Principle of Pressure Gauges

A pressure gauge works the principle which says; when you apply the pressure on the flattened tube, it will try to get straight in cross-section. However, you can hardly notice this change because it involves the minor stress remaining in the lower range of elasticity on workable materials.

You can notice the change in the shape and elasticity of the tube, which increases to change the tube in a C shape or even more complex in a helix. After reforming the tube, when you apply the pressure tube will tend to uncoil or straighten. As a result, there would be the accountable elongation of 2 to 3 millimeters in the size of the tube. This deflection in elasticity is your exact measure of changing pressure.

Which is More Accurate: A Bourdon Gauge or Electronic Manometer? 

In comparing pressure gauges VS manometers, by watching the principle of manometers and power gauges, you can see manometers are found easier to use. The best thing about electronic manometers every technician may love, is it’s compact size, and portability. 

The type of manometer always stands out from other pressure measurement instruments regarding accuracy and resolution.