What is a Pressure Gauge and How Does it Work?

Posted by David Cannon on 2nd Apr 2020

What is a Pressure Gauge and How Does it Work?

A pressure instrument is a device that measures the pressure of a gas or liquid. Pressure is typically measured in units of force per unit of surface area. A pressure gauge is a measuring instrument used to measure the level of pressure in a liquid or gas, across industries. It is a crucial instrument as it also helps control the levels of pressure in liquids and gases and keep them in the required limit. 

The measuring mechanism in a pressure indicator or instrument can be electronic, mechanical or both. Mechanical measuring mechanisms use a pointer to indicate the pressure, while electronic measuring mechanisms use a digital display.

It raises an alarm in case the pressure exceeds. This is important from a safety perspective because an instrument or machine may explode if the pressure level exceeds and goes unnoticed for a long time. This may harm the workers as well as damage the equipment. So, a pressure gauge is crucial for overall plant safety. This post discusses the working principle and other details of a pressure gauge meter.

A Brief Discussion on the Working Principle of a Pressure Gauge

The working principle of  pressure gauges is based on Hooke’s law, which states that the force required to expand or compress a spring scales in a linear manner with regards to the distance of extension or compression. There is inner pressure and outer pressure. So, when pressure is applied on the surface of the object, it is more on the inner side as the pressure area is less. Bourdon pressure gauges are widely used across industries, and they work on this principle.

Digital pressure gauges are nowadays commonly used. In case of digital pressure gauges, the AC and DC power supplies play a major role. The switching circuit or AC is converted to DC. The measured pressure is transmitted to the sensor diaphragm which senses the pressure, based on which an electrical signal is generated to reach to the computer or smartphone. These gauges come with a small LCD display.

pressure gauge

Other Important Details of Pressure Gauges

Pressure gauges range from basic measuring ones to completely automated ones, which can be connected to your smartphone to send alerts. Pressure sensors are crucial components of pressure gauges. There are various types of pressure gauges in the market such as commercial gauges, general service gauges, stainless steel industrial pressure gauges, differential pressure gauges, double-sided pressure gauges, and so on. With so many choices, it is obvious to get confused. Among various factors, the size of an application must be one of the key considerations when it comes to choosing it for any process. It need to be serviced and maintained regularly as an out of service gauge is as much a threat to the plant as not having one. So, it is always better to have few but well-serviced gauges in your plant. From an accuracy perspective, installing and correct calibration of the pressure gauge are important aspects. Calibration can be a complicated task and needs to be done by experts, after considering the application requirements.

A Focus on Double-Sided Pressure Gauges

Double-sided pressure gauges are one of the most important types of pressure gauges. They are widely used in industries such as chemical and oil & gas. Here are some beneficial features of it:

  • Mostly made of a plastic body, they have a heavy duty rugged design.
  • They are resistant to chemicals, corrosion, abrasive materials, high temperatures and so on.
  • They are highly accurate and compatible in multiple pressure ranges.
  • They have a Bourdon tube Teflon diaphragm.
  • They are molded as a single piece and hence cannot be assembled or disassembled.
  • You do not require any filling for these gauges, as they are pre-filled with glycerin or optical silicone gauge fluid.
  • They come with a polycarbonate lens, which has a high impact resistance and a colored display with bright range tabs.
  • They come with a dual scale and you can choose the unit between PSI/KPA and PSI/BAR.
  • They have an alert mechanism in case the filter or BAG need to be replaced.
  • These are suitable even in areas where visibility is an issue. You can install on machines or chemical pumps in such areas.

If you are a manufacturer in oil & gas or other such industries, you would need high-quality pressure gauge meter. Ensure you study all the features of the gauge and the autonomy of its operation, and source them from certified and trusted manufacturers and suppliers. Cannon Water Technology is one of the well-known distributors of various types of pressure gauges and other test and water treatment equipment. The company stocks gauges made by reputed and trustworthy brands.

Truflo OBS Plastic Pressure Gauge With Isolator, Chemical Resistant

Truflo 2VU Double Sided Pressure Gauge With Isolator, Chemical Resistant