The pressure in the compressor industry refers to the pressure (P)
The force of 1N per unit area is 1Pa, that is, 1Pa = 1N / ㎡, Pa is the basic unit of pressure. When the pressure value is large, kPa (1kPa = 1000Pa) and MPa (1MPa = 1000000Pa) are available.
Ⅰ Standard atmospheric pressure (atm)
Ⅱ gauge pressure and absolute pressure
① The pressure measured with a pressure gauge is the gauge pressure. It is the difference between the pressure in the container and the local atmospheric pressure. It is the pressure measured at the zero point of atmospheric pressure and is expressed by P (G).
② The pressure with absolute vacuum as the zero point is called absolute pressure, which is the sum of the pressure in the container and the local atmospheric pressure, which is expressed by P (A).
The relationship between gauge pressure and absolute pressure: gauge pressure + atmospheric pressure = absolute pressure
Usually the discharge pressure given on the compressor nameplate is the gauge pressure.
Working pressure
Suction and exhaust pressure refers to the pressure of air compressor suction and exhaust
The gas pressure measured at the intake flange of the first-stage cylinder working chamber of the compressor and the exhaust flange of the last-stage cylinder working chamber is called the suction and discharge pressure of the compressor.
In some cases, the discharge pressure of the compressor is also called "back pressure"
The suction and exhaust pressure of the screw air compressor refers to the suction and exhaust pressure of the entire air compressor. Generally speaking, the working pressure of the air compressor refers to the exhaust pressure.
Ⅵ Common pressure unit conversion for air compressor
1MPa (Mpa) = 1000kPa (KPa) = 1000000Pa (Pascal)
1bar (bar) = 0.1MPa
1atm (standard atmospheric pressure) = 0.1013MPa = 1.013bar = 760mmHg = 10.33mH2O
1kgf / cm2 (engineering kilogram force) = 0.981bar = 0.0981Mpa
1psi (Lb / in2) = 0.07031kgf / cm2 = 0.06893 bar = 6.893kpa
1MPa = 145psi
Psi (lb / in2) pounds per square inch, commonly used in product parameters of European and American English-speaking countries
Generally speaking, "kg" in the air compressor industry refers to "bar"
