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Oil-free pumps meet industrial analytical needs

Edited by the Engineeringtalk editorial team Jan 16, 2001

Welch Vacuum has developed a range of small, oil-free, standard duty dry piston pumps and patent pending diaphragm pumps for industrial analytical applications and general industrial duties

Welch Vacuum has developed a range of small, oil-free, standard duty dry piston pumps and patent pending diaphragm pumps for industrial analytical applications and general industrial duties such as vacuum packaging and electronic component manufacture.

These compact, competitively priced pumps offer high flow rates at low pressures, whilst at the same time overcoming the inherent unreliability problems of many other designs.

The range includes single and two-stage dry piston pumps offering flows from 1m3/hr to 10m3/hr.

The single stage pumps in the range can provide ultimate pressures of 80mbar, whilst the two stage designs offer ultimate pressures of 10mbar.

Typical applications for the pumps include gas analysers, analytical instruments, dental ovens, drying, vacuum packaging and semiconductor manufacturing processes.

Also included in the range is a two-stage diaphragm pump designed for backing turbo molecular pumps, providing an ultimate pressure of 2mbar.

Being dry running, all the pumps in the range run without the possibility of contaminating the process with oil mist.

In addition, both the piston pump designs and the diaphragm pump designs overcome the practical problems which can lead to the reduced effectiveness or early failure of oil-sealed rotary vane pumps.

For standard duties, the dry piston pumps in the range eliminate the problems of unreliability and frequent breakdowns that beset oil-sealed rotary pumps.

At the same time, the vacuum against flow rate curves for these piston pumps are vastly superior to those of membrane pumps, giving far higher flows at any given vacuum to ensure a more consistent operation and giving longer life operation, or allowing a physically smaller pump to be used to perform any given task.

The PTFE diaphragm pump also improves on other designs, delivering excellent performance in a very small package.

Using forced valve operation (patent pending) and minimal dead space, the best performance in a 2-stage diaphragm is achieved.

The innovative dry pump is designed as a backing pump for hybrid turbomolecular and molecular drag pumps used in applications such as helium leak detectors, mass spectrometers, MVD chambers, electron microscopes, surface science engineering, reaction cell analysers, and in electron microscopes.

Additionally it may be used for dental vacuum ovens and degassing polymers.

Other applications may also be found in medicine or analytical engineering.

The two-stage standard duty diaphragm pump delivers 2mbar ultimate vacuum with a free air displacement of 32 L/min The new valve technology is very efficient, with the suction valve located at the very edge of the pump chamber.

Small and lightweight, all the pumps in the range benefit from volume manufacture, ensuring highly competitive prices.

A complete range of highly reliable and competitively priced Welch vacuum pumps and systems is available across Europe from ASF Thomas, along with a correspondingly high level of local service and support.