Table of Contents

What is a Pressure Gauge
A pressure gauge is an instrument used to measure a liquid or gas inside of a machine or tank. The gauge works by reading the force/pressure that is being applied from the fluids inside a tank or piece of equipment and then outputting that measurement on a dial or digital output.
Common Places to Find a Pressure Gauge

Cars have gauges to measure things like tire pressure which uses a type of pressure gauge and sensor, a lesser-known thing it is used for is measuring your oil level. These are all done by reading the pressure that these fluids are producing or lack thereof.
Ever seen the dashboard of an aircraft? Airplanes and other aircraft are filled with dial readings of things about the aircraft, things like fuel pressure to atmospheric pressure are all accounted for.
Chemicals don’t make themselves. The Chemical manufacturing world relies on pressure gauges. Moving large amounts of fluids from container to container accurately is vital. Having improper measurements can have lasting effects on consumers which is why the chemical industry has strict accuracy requirements.

Types of Pressure Gauges
Absolute pressure gauges
Absolute pressure is found by comparing the pressure to the pressure in a vacuum or an area where there is no pressure. These gauges have a measuring cell that is separated by a diaphragm making up a mechanical absolute pressure gauge.
Bellows Pressure Gauges
Bellows gauges are made with an accordion-looking tube that is connected to a spring and a pivot that when pressure is applied the spring extends as the pressure increases and the tubes condense giving you an accurate reading. These types of gauges are commonly used in low-pressure situations as they are sensitive gauges.

Bourdon Pressure Gauge
Bourdon Pressure gauges have a Bourdon Tube, this tube looks like a c-shaped tube. This tube is open to the atmosphere at one end and closed on the other. Any increase in system pressure within the tube causes the tube to expand and straighten, the change is small but magnified due to the shape of the tube.

Capsule Pressure Gauge
The capsule pressure gauge has two thin diaphragms that are sealed together. One of these has a hole to allow for the medium to enter, while the other is sealed. When pressure is applied the diaphragms expand or contract changing their shape. The created movement then appears on the face of the gauge. Capsule gauges are used almost always for measuring the pressure of gases.
Differential Pressure Gauge
These pressure gauges measure the difference between the two chambers. Separated by a piece that moves back and forth, the pressure is then measured by to the moving piece. This moving piece causes movement on the pointer on the face of the gauge providing a reading. These gauges are fairly common for their simplicity.

Get Pressure Gauges
Looking to buy pressure Gauges? GR Metrology supplies pressure gauges and can service them. GR Metrology does pressure gauge calibrations. Get yours today.