Respectively Oil-Free Compressing Vacuum Pumps

In accordance with DIN 28 400 (Part 2) a dry compressing vacuum pump is a positive displacement vacuum pump which operates without an oil seal (as the liquid seal). A diaphragm vacuum pump is a dry compressing pump, a type of pump which chiefly has its role in connection with laboratory apphcations. Here the diaphragm vacuum pump replaces the universal laboratory water jet pumps, the water consumption of which and thus the high operating costs due to the generation of contaminated waste water are factors which are not desired. 

The diaphragm vacuum pump which in connection with chemical production facihties is practically of no great significance is not covered here. Information on this kind of pump can be found in [2]. 

For the same reasons on which the move in the chemistry laboratory to dry compressing vacuum pumps is based, dry compressing pumps have also been developed for chemical production facilities. The different pumps operate according to 

Chiefly the following fundamentally known vacuum pump principles have been relied on in the development of oil-free compressing pumps  

Dry compressing rotary vane vacuum pumps based on multi-vane designs with self-lubricating vane materials are hardly used. This dry compressing type of vacuum pump has been found to be too prone to wear if used in chemistry applications. 

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