Overview
The HT high throughput series is the pinnacle of our diffusion pump knowledge with technology aimed specifically at industrial users. Edwards diffusion pump is designed for all light and heavy duty industrial applications. The robust construction gives high pumping speed at high pressure. The cast and machined aluminium interior provides consistent performance, while the stainless steel body prevents corrosion and ensures process cleanliness. These pumps are designed to give a high throughput (pressure multiplied by pumping speed) at 4 × 10-3 mbar making them ideal for industrial processes that involve large quantities of gases.
Technology
Industrial applications require robustly constructed vapor pumps often with very high throughputs. Edwards provides a range of vapor diffusion pumps and vapor booster pumps to meet these needs. All industrial diffusion pumps are water-cooled.
All Edwards diffusion pumps are fully fractionating. This means that volatile components are fed to the lower stages of the vapor pump and the vapor fed to the inlet stage is stripped of these fractions. This improves ultimate vacuum. Cooled baffles above the pump help to prevent pump fluid condensing on the pump walls, which would prevent the pump attaining its ultimate vacuum. Baffles will also minimize backstreaming.
The ultimate vacuum obtainable with a diffusion pump is dependent upon the parameters of the system under evacuation. The outgassing from the system, its leak tightness, the vapor pressure of the pump fluid and the number of joints and elastomers used all contribute to the achievable vacuum. Additionally, in most industrial applications, the pumps throughput at a particular pressure is more important than obtaining a very low pressure. For these reasons we have elected not to quote an ultimate vacuum for our HT series industrial vapor diffusion pumps since it would not be meaningful.