Pressure Control and Measurement

Fluid pressure measurement

Fluid pressure measurement analyzes an applied force by a fluid, liquid or gas, on a surface. Pressure is typically measured in units of force per unit of surface area.

How is fluid pressure measured?

Many techniques have been developed for the measurement of pressure and vacuum. Instruments used to measure and display pressure in an integral unit are pressure meters, pressure gauges, or vacuum gauges. A manometer uses the surface area and weight of a liquid column to measure and indicate pressure. Likewise, the widely used Bourdon gauge, a mechanical device, measures and indicates.

Other pressure measurement methods involve sensors that can transmit the pressure reading to a remote indicator or control system.

Why is it important to measure fluid pressure?

Across various industries, measuring the pressure of a substance is an integral part of the manufacturing process. Obtaining accurate and meaningful data is vital in determining the quality and consistency of the product. For these reasons, accurate sensors are critical in receiving this information. Each sensor takes the physical pressure of the element and transfers it into electrical energy of some kind that can be measured.

 

Types of pressure measurement

Pressure measurements can be divided into three different categories: absolute pressure, gauge pressure, and differential pressure.

Absolute pressure refers to the total value of the force per unit/area exerted by a fluid surface. Therefore, absolute pressure is the difference between the pressure at a given point in a fluid and total zero pressure or a perfect vacuum. Gauge pressure is the difference between absolute pressure and local atmospheric pressure, and local atmospheric pressure can vary depending on ambient temperature, altitude, and local weather conditions.

Differential pressure is simply the measurement of one unknown pressure concerning another unknown pressure. The pressure measured is the difference between the two unknown pressures. This pressure measurement is commonly used to measure the pressure drop in a fluid system. Since a differential pressure measures one pressure referenced to another, it is not necessary to specify a pressure reference.