U 4.400 SA/K + U 4.400 F/K
 U 4.630 SA/K + U 4.630 F/K

... The standard-featured circulating-oil lubrication system with integrated oil cooler and cover additionally minimise noise emission. Controlled by a float valve, the oil return suction system also makes these vacuum pumps suitable for use in rough-vacuum applications. Optional water cooling significantly prolongs the life of the oil, even in difficult ambient conditions.

Optional gas ballast valves prevent condensing vapours from contaminating the pump oil. The oil-water emulsion arising from contamination reduces the pump effi ciency or leads to a failure. The valve permits a regulated amount of fresh air (the gas ballast) to fl ow into the pump‘s compression chamber. By mixing saturated intake air with unsaturated fresh air, condensing is suppressed. 

The new generation of oil-lubricated rotary vane vacuum pump: U 4.300

The new size between U 4.250 and U 4.400.

U 4.300 - U 4.250: comparison and differences:

• realization of faster pump-down times
• realization –for example– of more packaging cycles per unit time
• as far as possible to keep up with the dimensions
• to keep up with the installed motor capacities of 5.5/6.3 kW respect. 7.5/8.6 kW (50/60 Hz)
• in general: rise in productivity of our customers machines and systems
• increased air flow
• decreased dead storage capacities
• no differentiation between versions SA/K and F/K; the only remaining pump is a version with a final pressure of
• axial lubrication of the rotor for a secured final pressure
• improved oil return suction at free air
• decreased pressure differential
• decreased power consumption
• improved noise level during cold start-up