100% oil-free vacuum pump

THE VARODRY is a completely oil-free, dry compressing screw vacuum pump that has several applications including food-related freeze drying, says Leybold GmbH. The new pump tolerates the rigors of industrial processes such as handling of particles, dirt, and vapors. Like an extruder, it pushes out disturbing particles together with the regular material at its exhaust. Its variable inlet flange arrangement enables a flexible installation of the pump within the plant. The pump's integrated silencer for quiet operation has no “sponge-like” damper materials. The exhaust flange located at the lowest point of the pump facilitates pushing-out liquids or condensed vapors. This prevents potential formation of rust and contributes significantly to process reliability. 

Being completely oil free, Leybold's vacuum pump will have a significant impact on cost reduction and process room cleanliness.

VARODRY has a process advantage in that it can operate continuously at any inlet pressure and is fully resistant even against repeated shock venting. Any number of cycles can be run without overload, which is still not the current market standard, according to Leybold.

Since VARODRY is 100% oil-free, there is no chance for lubricating oils to migrate from gear chamber to the pumps compression chamber. The vacuum pump uses grease-lubricated bearings and there are no oil-lubricated synchronization gears. Drive and synchronization are done with a high-tech tooth-belt, which on demand can be exchanged by the user himself in a matter of minutes. This also eliminates the gear oil exchanges which are still required at other screw-type pumps. No oil will migrate back to the process chamber, be blown out of the exhaust, or leak on the floor during gear-box exchange. The VARODRY is therefore the first pump on the market which is 100% oil-free – this will have a significant impact on cost reduction and process room cleanliness. 

Another technical advantage for industrial use is the pump’s complete air cooling. This simplifies the integration of the pump into the plant as there is no need for water supply.

In contrast to most competitor products, the VARODRY has a moderate temperature profile. The low internal temperatures which peak around 100 to 130°C (depending on operation point) also allow a handling of temperature sensitive media, often preventing that those react immediately and build-up layers inside the pump. This moderate heat is the optimum for many applications enabling long-time operation without need for compression room cleaning.

The screw vacuum pumps will initially be available in sizes VD65 (65 m³/h) and VD100 (100 m³/h); sizes VD160 and VD200 are already in preparation.