10 Different Types of Pressure
1 Atmospheric Pressure
Atmospheric pressure is the force of pressure exerted by the earth’s atmosphere. Atmospheric pressure at sea level is equivalent to 14.695 psia. The value of atmospheric pressure decreases with increasing altitude.
2 Barometric Pressure
Barometric pressure is the same as atmospheric pressure.
Gauge pressure is a single pressure measurement that indicates the pressure above atmosphere. Gauge pressure represents the positive difference between measured pressure and existing atmospheric pressure. You can
convert gauge pressure to absolute pressure by adding the actual atmospheric pressure value to the gauge pressure reading. For example, 10 psig is equivalent to 24-7 psia. 0 psig is equivalent to 14.7 psia.
Vacuum pressure is a single pressure measurement, which also has a reference to atmospheric pressure. Vacuum pressure is the measure of the depression of process pressure below atmospheric pressure means the pressure which is measured below atmospheric pressure.
Vacuum pressure is generally measured in cm or inches of H20. For example, 14.7 psia is equivalent to 407.5 inches of H20. Therefore, a pressure of 10 inches of H20 vacuum implies process pressure is depressed 10 inches below atmosphere. Or 10 inches of H20 vacuum is equivalent to 397.5 inches of H20 absolute. Vacuum pressure is typically measured using a gauge pressure transmitter with an elevated zero calibration.
5. Line Pressure
Line pressure is simply the amount of pressure, or the force per unit area, exerted on a surface by the flow parallel to a pipe wall.
6. Static Pressure
Static pressure is the same as line pressure.
Working pressure is also referred to as the line or static pressure.
8. Hydraulic Pressure
The Pressure that is exerted by the oil in any process line or tank is known as Hydraulic Pressure.
9. Pneumatic Pressure
The Pressure that is exerted by the air in any line, body or Tank is known as Pneumatic Pressure.
10. Differential pressure: The pressure gauge contains two process connections to measure the difference between two pressures, such as each side of a filter to measure pressure drop.