What is pressure?
Pressure is the amount of force applied perpendicular per unit area.
Pressure can be divided into absolute pressure and gauge pressure according to its reference point.
Everyday pressure measurements, such as for vehicle tire pressure, are usually made relative to ambient air pressure. In other cases measurements are made relative to a vacuum or to some other specific reference. These zero references distinguish different types of pressure.
Types of Pressure
Absolute Pressure：
Absolute pressure is zero-referenced against a perfect vacuum, using an absolute scale, so it is equal to gauge pressure plus atmospheric pressure. Absolute pressure sensors are used in applications where a constant reference is required, like for example, high-performance industrial applications such as monitoring vacuum pumps, liquid pressure measurement, industrial packaging, industrial process control and aviation inspection.
Gauge Pressure：
Gauge pressure is zero-referenced against ambient air pressure, so it is equal to absolute pressure minus atmospheric pressure. A tire pressure gauge is an example of gauge pressure measurement; when it indicates zero, then the pressure it is measuring is the same as the ambient pressure.
Since ambient air (or atmospheric) pressure is a pressure of weight of ambient air (atmospheric), pressure changes depending on the atmospheric pressure fluctuations caused by the measurement location, weather, etc. Therefore, when measuring with a pressure gauge, it is necessary to take the atmospheric pressure into account and correct it before checking the pressure.
Differential Pressure：
Differential pressure is the difference in pressure between two points. Differential pressure sensors are used to measure many properties, such as pressure drops across oil filters or air filters, fluid levels (by comparing the pressure above and below the liquid) or flow rates (by measuring the change in pressure across a restriction). Technically speaking, most pressure sensors are really differential pressure sensors; for example a gauge pressure sensor is merely a differential pressure sensor in which one side is open to the ambient atmosphere.
What is a Pressure gauge??
Instruments used to mechanically measure and display pressure are called pressure gauges, and there are various types depending on the reference point and measurement range.
The relationship between pressure types and pressure gauges is as shown in the diagram below.
Pressure gauges are named differently depending on the range: pressure gauges for positive pressure only, vacuum gauges for negative pressure only, and compound gauges for positive and negative pressure.
To summarize, they are as follows:
We will provide the future of customers.(81)467-87-1552
Inquiry Please send E-mail