Oil sealed pumps D.V.P. Vacuum Technology
Oil sealed high vacuum pumps are used when the final absolute pressure required is very low. These pumps may run continuously connected to closed containers to be emptied, and may not run continuously at length, at atmospheric pressure. The exhaust from these pumps is not filtered, thus, special purifiers are available for fumes.
The operating principle of these pumps is similar to the lubrificated pumps one. However, in this case, the stator is immersed in the lubrification oil which has also the function of sealing the air loss. The pressure levels reached by this type of pumps are higher than any other rotary vane pump. These pumps are equipped with a Gas Ballast system to avoid the condensation of the water vapour.
These kind of pumps can be made of a single rotor-stator group and are called Single Stage; or they can be made of two rotor-stator groups connected in series so the first group drain is connected to the second group intake system. The latter are called Double Stage.
The main application fields include: refrigeration and air conditioning systems, laboratory applications, freeze-drying, spectrometry and ultracentrifugation. Special Pneurop fittings are available to connect the various elements of the system.