The HT high throughput series is the pinnacle of our diffusion pump knowledge with technology aimed specifically at industrial users.
Edwards HT20B (ANSI20/ISO630 inlet) 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.


Features and Benefits

  •     Highest throughput of comparative sized pumps
  •     Earliest crossover pressure of similar sized pumps
  •     Excellent maximum backing line pressure and tolerance to gas surges
  •     Comparative pumping speed to similar sized pumps
  •     Integral cold cap for best performance and low backstreaming
  •     Self fractionating for low ultimate pressures

Easy change heater assembly


  •     Vacuum metallurgy
  •     Distillation, drying and degassing
  •     Thin film coating and metallizing
  •     Large-scale research
Dane techniczne
Comparative pumping speed 18000 ls-1
ISO pumping speed†  
  Nitrogen 8000 ls-1
  Helium 16000 ls-1
Max throughput (nitrogen) 24 mbar ls-1
  18 Torr ls-1
Critical backing pressure (DC704EU) 1.3 mbar /
  1 Torr
Min backing pump displacement for max throughput 135 m3h-1
  80 ft3min-1
Recommended backing pump‡ GXS250, E2M175
Recommended fluid DC704EU
Fluid charge (dry) 3600 ml / 3.8 qt
Inlet/backing connection ANSI20/ANSI4 or
Water connection 3/4 inch NPT female
Heater power 12.6 kW / 16.9 hp
Warm up time 60 min
Minimum cooling water flow at 25°C 960 l h-1 / 4.2 US gal min-1
Pressure drop across cooling water supply 1.2 bar / 17.4 psi
Weight 275 kg / 605 lbs

† ISO speed and throughout data obtained with total pressure measurement. Partial pressure readings typically increase data by ~30%. ISO speed measurements are typically 10% less than AVS measurements for the same pump.
‡ These are given for guidance

Pliki do pobrania
HT20B High Throughput Diffusion Pump Datasheet