1. Internal compression ratio (ie internal pressure ratio)
The ratio of the final pressure (absolute pressure) of the gas after internal compression to the initial pressure (absolute pressure).
2. External compression ratio (ie external pressure ratio)
The ratio of the compressor 0010010 #39;s outlet discharge pressure (absolute pressure) to the inlet suction pressure (absolute pressure).
For screw air compressors, the internal compression ratio refers to the pressure ratio (absolute pressure) of the suction and exhaust ports of the screw host, and the external compression ratio refers to the pressure ratio (absolute pressure) of the air compressor suction and exhaust ports .
Generally speaking, the compression ratio of an air compressor refers to the external compression ratio, the suction pressure refers to the local atmospheric pressure, and the exhaust pressure refers to the rated working pressure of the air compressor. When the discharge pressure is 8 bar, the compression ratio is 9.
For multi-stage compressors, the pressure ratio is also called the total pressure ratio, which refers to the ratio of the exhaust pressure measured at the last-stage exhaust pipe connection to the intake pressure measured at the first-stage intake pipe connection. The ratio of the nominal suction and discharge pressures of the corresponding levels is called the level pressure ratio.
