Two-Stage Liquid Ring Vacuum Pumps PW2 Hydro-Vacuum



Vacuum pumps– are designed for suction and pumping of dry gas, with temperature up to 150°С, and vapour saturated gases, distinguished by the fact that their temperature does not exceed 100°С, and the possibility of the use of working media with its viscosity up to 60 mm²/s and density of 800-1200 kg/m³; water temperature at the outlet of the pump must not exceed 80°С.

"Hydro-Vacuum" produces two stage vacuum pumps with their main distinguishing feature of achieving deeper vacuum (33-40 mbar abs.) in comparison with single stage pumps. Maximum capacity and productivity ranges between 100-200 mbar abs.

Characteristic feature of these pumps is the built-in anti-cavitation valve which comes between pump stages. The pumps are robust, easy to operate, and are able to discharge almost any gaseous media or vapour. PW1-21 – PW7-24 liquid ring vacuum pumps appear to be two stage vacuum pumps

Ultimate pressure up to 33 mbar, pump capacity ranges from 4.5 till 1600 m³/h

Property Sheet

Model QR - Capacity,
PS - Intake pressure,
P-power of motor,
Sizes (LхWхH),


PW1.21 10.5 40 0.75 694x240x250 46.9
PW1.22 22.0 40 1.1 728x240x250 49.0
PW1.23 50.0 40 2.2 815x240x260 56.0
PW4.21 81.0 40 4.0 1013x342x482 148.0
PW4.22 110.0 40 4.0 1033x315x482 151.0
PW4.23 180.0 33 5.5 1148x315x482 174.5
PW4.24 220.0 33 7.5 1226x315x482 196.0
PW5.21 285.0 33 11.0 1240x415x563 303.0
PW5.22 360.0 33 11.0 1280x415x563 299.0
PW5.23 420.0 33 15.0 1387x396x563 344.5
PW5.24 515.0 33 18.5 1487x396x563 395.5
PW7.21 700.0 40 30.0 2040x640x903 1056.0
PW7.22 920.0 40 30.0 2185x665x903 1081.0
PW7.23 1250.0 40 37.0 2410x700x903 1331.0
PW7.24 1600.0 40 45.0 2590x750x903 1480.0

Field of application of liquid ring vacuum pumps

  • Chemical industry
  • Pharmaceutical industry
  • Food industry
  • Cellulose and paper production
  • Textile industry
  • Filling of centrifugal pumps and siphons
  • Brick and cement production
  • Foundry production
  • Wood processing industry

Design features of liquid ring vacuum pumps Hydro-Vacuum

The pumps are designed and manufactured according to the ISO 9001 standard. All the manufactured pumps, submitted at the stalls, undergo detailed checkouts and tests. Wide range of construction materials used in vacuum pumps manufacturing is shown in Table below.

Cast iron framing.
The pumps are equiped with various types of seals depending on the customer's demand:

  • Soft cord packing seal №6498
  • «ANGA» 43А1 Mechanical seal
  • «Crane»2100 Mechanical seal

Various protection coverings are available

  • Standard
  • Special

Possibility of choosing scope of supply

  • Pump with a free shaft end.
  • Pump with coupling.
  • Pump with coupling and bed plate.
  • Complete set No3 with electric motor.

Availability of spare parts even after the decades of operation
Warranty period is 24 months

Property sheet of operation of two stage liquid ring vacuum pumps of PW.1.21 - PW.7.24 Series

Таблица параметров работы двухступенчатых водокольцевых вакуумных насосов PW.1.21 - PW.7.24

PB– operation of liquid ring pump with fresh liquid supply

PZ– operation of liquid ring pump in the system with partial liquid recirculation

∆t0C– increase of water temperature has been observed in the pump when operated in PZ mode, as compared to the PB mode operation

Values taken for pump capacity refer to air with its temperature of 20°С, under atmospheric pressure (1013 mbar abs), with application of water (as working medium) with its temperature of 15°С (measured at the pump outlet).

Interchangeability table of BBH liquid ring vacuum pumps and PW vacuum pumps

Advantages of Hydro-Vacuum vacuum pumps of PW Series compared to the vacuum pumps of BBH Series:

  • Possibility of using one stage and two stage vacuum pumps depending on requirements of technological process.
  • High vacuum level (up to 33 mbar abs)
  • Possibility of equipping with the tank which is designed for closed-circuit systems of working medium supply (water saving)
  • Wide range of construction materials
  • Possibility of equipping with various types of seals
  • Big model range of vacuum pumps
  • Use of low-power electric motors
  • Possibility to choose scope of delivery
  • Full sale technical support