Piston type vacuum pumps and compressors are being used where oil-free air is crucial. The oil free character of the pump can be a guaranty of zero-maintenance costs. The pumps are Piston Vacuum Pump china available in capacities of maximum 6 m3/hr and 
they are capable to reach vacuum pressure of 10 mbar(a). Used since a compressor they reach a pressure of approx. 7 bar(g) optimum.
These pumps are getting used for light industrial functions, medical industry, printing and device industry, plastic, meals and packaging, electronic, chemical and textile industry.