Clean operation (oil free), low cost of ownership, highest reliability – these are just a few benefits that customers can appreciate when they use a diaphragm pump for laboratory or industrial applications. With a broad range of diaphragm pumps – ultimate vacuum from 75 to 1 mbar and peak flow rates up to 138 l/min – Welch offers specific pump families and models for a variety of uses.

These pumps have superior vapor tolerance and have a gas ballast valve for handling heavy vapor loads. The gas ballast valve preserves the pump performance under heavy vapor load by leaking air into second stage to inhibit condensation.