The term “pressure gauge” is commonly heard in the industrial world. So, what exactly is a pressure gauge, and what are its functions? Let’s take a closer look at the following article to learn more.

Definition of a Pressure Gauge

A pressure gauge is a safety device that is essential in industrial applications. It is generally used to measure and monitor air or gas pressure. The pressures being monitored may include compressor pressure, vacuum equipment pressure, process line pressure, medical equipment pressure, and fire extinguisher pressure. Pressure readings are typically displayed through numbered scales inside the gauge.

The use of this device is not limited to visual monitoring only, as it can also be configured to provide electrical output from variable pressures and other parameters, such as temperature.

Pressure monitoring is very important for industrial safety. This is because industrial machines may explode if pressure levels exceed safe limits for an extended period. Such incidents can endanger workers and damage industrial equipment.

Working Principle of a Pressure Gauge

The working principle of a pressure gauge is based on Hooke’s Law. This system works by linearly expanding or compressing a spring scale. Hooke’s Law relates to the distance and pressure of extension or compression in a gas tube. In this system, there are two types of pressure: internal and external pressure. Therefore, when pressure is applied to the surface of an object, the resulting pressure is relatively smaller.

Pressure measuring instruments have been used for more than one hundred years. As a result, their designs have continued to evolve. Pressure gauges are generally divided into two types: analog and digital. Today, digital pressure gauges are widely used in industries. Digital gauges can operate using AC or DC power supplies.

In addition, pressure gauges can also operate automatically. Automatic gauges can be connected to smartphones to send alerts, allowing users to monitor gas or air pressure anytime through their smartphones. Monitoring is carried out using pressure sensors installed on important components. There are also various types of pressure measuring instruments available.

However, among the many factors involved, the size of the pressure gauge should be a major consideration. Therefore, selecting a pressure gauge for any process requires careful evaluation. In addition, pressure gauges need regular servicing and maintenance. Important maintenance aspects include ensuring measurement accuracy, proper installation, and correct calibration of the pressure gauge.

Functions of Pressure Gauges in Industry

Pressure gauges have several important functions in the industrial sector. Below are some of their primary functions:

1. Differential Pressure and Duplex Pressure Measurement

Both differential and duplex pressure gauges are capable of measuring three types of pressure: high pressure, low pressure, and static pressure. Therefore, pressure gauges are specially designed for optimal industrial use. They are commonly used in chemical industries, oil and gas industries, alternative fuel industries, and air handling systems.

2. Industrial Pressure Measurement

One common type of pressure gauge is made from stainless steel material. Stainless steel gauges are specially designed for ease of operation and durability. They are widely used in industries such as fuel oil processing, gas industries, chemical manufacturing, and other factory operations. The stainless steel design allows accurate pressure measurement without interfering with the pressure system of the equipment being measured.

With this tool, pressure measurements can also be read digitally. This helps prevent fatal errors in pressure reading. Many industries require pressure gauges to measure system pressure accurately and in detail. The resulting data can generally be considered reliable and precise.

3. Simplifying Pressure Operation Processes

Another function of a pressure gauge is simplifying pressure operation processes. In addition, this device has the advantage of being able to operate under any conditions, including extreme environments such as petrochemical industries. Due to its excellent durability, pressure gauges have become essential equipment commonly found in oil, gas, and chemical industries.

Types of Pressure

Pressure is determined based on perpendicular force per unit area, calculated through various techniques and methods. Accurate pressure measurement depends on the pressure reference being used. Pressure itself is divided into two main types:

• Hydrostatic Pressure: Pressure generated by the weight of a liquid above the measurement point when the liquid is at rest. The height of the liquid affects hydrostatic pressure. In addition, hydrostatic properties are influenced by gravity and fluid density, meaning hydrostatic pressure is not constant.
• Mechanical Pressure: Pressure measured using diaphragms, bellows, or Bourdon tubes, which convert fluid pressure into measurable force.

When discussing pressure, it is also important to understand several pressure dynamics, including absolute pressure, gauge pressure, differential pressure, and atmospheric pressure.

Absolute Pressure

Absolute pressure is pressure measurement relative to a vacuum.

Gauge Pressure

Gauge pressure is pressure measured relative to atmospheric pressure. This pressure is positive above atmospheric pressure and negative below atmospheric pressure.

Differential Pressure

Differential pressure measures the difference between two applied pressures. This measurement does not use a fixed reference because its purpose is to determine the difference between the two pressures.

Types of Pressure Gauges

There are several types of pressure gauges, including differential pressure gauges, pressure switches, pressure transmitters, and digital pressure gauges. Below is an explanation of each type.

1. Pressure Switch

A pressure switch is a device capable of opening or closing a contact when a certain pressure deviation is reached. The pressure limits for opening and closing can be automatically adjusted according to requirements. Unlike ordinary gauges, pressure switches also include pressure indicators.

2. Pressure Transmitter

A pressure transmitter is a type of transducer that converts pressure information into digital form. In industrial applications, transmitters function as system control devices with more accurate and stable measurement results.

In addition, this type of device does not require direct contact with other measuring instruments during operation. The data can be recorded and analyzed from a control room. Therefore, pressure transmitters are suitable for environments with high temperatures and various industrial applications.

3. Differential Pressure Gauge

Differential pressure gauges are instruments capable of measuring two pressures simultaneously. These include high or low pressure as well as static pressure. Differential pressure gauges are commonly used in petrochemical industries, power plants, oil and gas industries, EPC companies, and palm oil industries.

4. Digital Pressure Gauge

A digital pressure gauge is a pressure measuring device that uses zero reference relative to space pressure, while standard pressure gauges use zero reference relative to vacuum pressure. Therefore, the pressure value is equal to the gauge pressure plus atmospheric pressure.

Digital pressure gauges are widely used in industries such as marine, food and beverage, pharmaceutical, oil, and gas industries.

Tips for Choosing a Pressure Gauge

One important consideration when choosing a pressure gauge is the diaphragm seal. A diaphragm seal provides flexibility by isolating the fluid. This method allows pressure effects to pass through the pressure boundary without contamination from surrounding materials.

As a result, the purity of the fluid being measured in industrial factories is maintained, and the pressure sensor is protected from direct fluid exposure. Diaphragm seals are widely used in industries such as food and beverage production and pharmaceuticals.

Another tip when choosing a pressure gauge is to consider additional applications and accessories. Accessories such as syphons and valves are commonly used.

• Syphons are used to cool steam before it enters the measuring instrument, helping prevent damage to the gauge.
• Valves are used as gas or air control devices to regulate pressure. Valves come in various configurations and are generally used in hydraulic systems.

In addition to the pressure gauge information explained above, you can also find more information and solutions on the Winston Indonesia website. The homepage provides the information you need while also offering pumps and other industrial equipment to support your operational needs.