11 September 2020

Difference between single stage and multi stage compressor

The easiest way to explain the difference between a single-stage and multi-stage compressor is the number of times that the sir is compressed. In a  single-stage system, the air is compressed once, and in a dual-stage, the sir is compressed twice. So here this article gives the main key difference between single-stage and multi-stage compressors to better understand this topic.

Single-stage compressor:

In a single-stage piston compressor, the air is drawn into a cylinder and compressed in a single-piston stroke to a pressure of approximately 120 PSI. Then it is sent to the storage tank. All rotary compressor is a single stage.

Multi-stage compressor:

While in a multi-stage compressor the first step is the same except that the air is not directed to the storage tank, the air is sent via an intercooler tube to a second, smaller high-pressure piston and compressed a second time and compressed to a pressure of 175 PSI. Then it is sent through the aftercooler to the storage tank.

Difference between single-stage and multi-stage compressor:

  • In a single-stage compressor only one cylinder for the compression process, While in a multi-stage compressor more than one cylinder is connected in series.
  • In a single-stage compressor used in low-pressure ratio application, while in a multi-stage compressor achieve a very high-pressure ratio.
  • Volumetric efficiency is low for given pressure ration in a single-stage compressor whereas volumetric efficiency is high for a given pressure ratio.
  • The temperature of fluid due to compression is very high. No intercooler, while in Multi-stage compressor temperature is low. Intercooling is more efficient than cooling with a cylinder wall surface. It also reduces thermal stress.
  • In a single-stage compressor suitable for the light task, In a multi-stage compressor suitable for the heavy task. It can manage a larger load.
  • In a single-stage compressor large size of flywheel required due to high torque fluctuation, while in a multi-stage compressor provide more uniform torque, it needs a light flywheel.
  • In a single-stage compressor the size of the cylinder is very large when compared to the cylinders in the multistage compressor, While in In a multi-stage compressor individual cylinders are small when compared to single-cylinder compression.