RAM Whispair water-sealed rotary vacuum pumps are heavy-duty units designed with intergral-shaft ductile iron impellers with a segment waist contour. Whispair vacuum pumps reducce noise and power loss by utilizing an exclusive wrap-around plenum and proprietary Whispair jet to control pressure equalization - feeding backflow in the direction of impeller movement, thereby aiding rotation.

The headplates and rigid, one-piece casing are grey iron, while the drive end cover and gear cover are die-cast aluminium. Carburized and ground alloy steel spur timing gears are taper mounted on the shafts, secured with a locknut. Cylindrical roller bearings are used.

Piston rings reduce air leakage through the shaft openings in the headplates and lip-type oil seals prevent lubricant from entering the air chamber. RAM Whispair vacuum pumps incorporate thrust control, with splash oil lubrication at both ends of the unit. A hydrodynamic seal on the drive shaft prevents seal oil leaks.

All frame sizes are designed with detachable rugged steel mounting feet which permit in-field adaptability to either vertical or horizontal installation requirements.

The top shaft is extendedd for drive on side outlet vacuum pumps and either shaft can be extended for drive on bottom outlet vacuum pumps. An inlet spray nozzle and seal water flow meter are supplied for water injection.

Design Features

1. Low noise level, less operating power required
2. Improved volumetric efficiency & reduced operating temperatures
3. Alloy steel timing gears
4. Cylindrical roller bearings
5. Piston ring air seals - no springs, valves or vanes to wear
6. Lip-type oil seals, hydrodynamic drive shaft seal
7. Splash oil lubrication
8. Horizontal and vertical configuration availability

Operating Principal

Incoming air is trapped by the impellers. Simultaneously, pressurized air is being discharged. As the lower impeller passes wrap-around flange, Whispair jet equalises pressure between trapped air and discharge area, aiding impeller movement and reducing power. Impellers move air into the discharge area. Backflow is controlled, resulting in reduction of noise relative to conventional vacuum pumps.