622 MH25

Stokes 6" series mechanical boosters are designed to be used in conjunction with rotary-piston, dry vacuum, rotary vane and liquid ring pumps to increase pumping speed at working pressures and shorten pump down time significantly. The Stokes 6" series can be mounted separately or on the inlet of the backing pump to create a compact integrated package.

Features and Benefits

  • Mechanical shaft seal – improved life and serviceability
  • Ringfeder® keyless gear locking system – stronger, faster timing
  • Large shaft diameters – allowing improved performance at high pressures
  • Belt drive or direct drive capability
  • Vertical or horizontal gas flow  
  • Drive end roller bearing – resists belt pull and thermal effects
  • Over-sized anti-friction bearings – increased uptime and longer service intervals
  • Rugged proven design and construction
  • Quiet operation
  • Unique impeller design -Dynamically balanced to minimize vibration
  • High volumetric efficiency
  • High differential pressure – operation capability
  • Available by-pass option for improved pumpdown
  • Available process isolation seal option – optimum protection from dust and particulate contamination


  • Automotive
  • Chemical processing
  • Heat treatment
  • Leak detection
  • Metallurgy
  • PET processing
  • Pharmaceuticals
  • Thermal processing
  • Transformer drying and cable fluid conditioning
  • Vacuum coating
  • Vacuum melting
  • Many other industrial applications
Technical data  
V belt (2750 rpm) 5100m3h-1 / 3000ft3min-1
Direct drive (3000 rpm) 5525m3h-1 / 2350ft3min-1
Direct drive (3600 rpm) 6630m3h-1 / 3900ft3min-1
Inlet/outlet flanges 8” ASA/ANSI flange
Motor power EU/Asia 18.5kW
Motor power US TEFC 25hp
Cooling method Air cooled
Oil capacity (horizontal flow) 1.9 litre / 0.51gal
Oil capacity (vertical flow) 4.1 litre / 1.1gal
Max pressure differential 333mbar / 250Torr
Max temp rise 151°C / 275°F
Max discharge temp 177°C / 350°F
Weight bare shaft 335kg / 740lbs
Weight TEFC direct drive 617kg / 1360lbs
Recommended Oil  V- Lube H