Start the prime mover and the compressor crank begins to run, driving the step piston to move up and down. Each working volume begins to shorten in proper order and recycle with variation. The air is admitted in the compressor from the atmosphere via filter cap and compressed in three cylinders successively as to achieve desired final pressure. Air after each-stage compression shall be cooled and then proceed into next-stage cylinder working volume for further compression. Finally, the compressed air is charged in the cylinder after oil-water separation via the separator.
Crankcase assembly: steel casting crankcase is used to support the crank and fix first-stage and second-stage cylinders.
Compressor cylinder assembly: divided into first-stage and second-stage cylinders, third-stage cylinder and cylinder cap.
The first-stage and second-stage cylinders are made of cast iron in a whole with first-stage at the upper and second-stage lower.
The third-stage cylinder is made of cast iron and fixed to the first-stage and second-stage cylinders.
The third-stage cylinder cap made of casting steel has four screws fixed on the cylinder via studs.
On the cylinder cap, there is mounted with second-stage safety valve and third-stage inlet and outlet valves covered by the cap.