Screw pumps guarantee a high level of vacuum and a smaller oxygen residue in the package. By working in a good manner and without oil, they can be installed in white chambers. Service Air can organize tests for those who want to evaluate the replacement of an old rotary oil-lubricated vacuum pump with a new screw pump, in order to cut maintenance and energy costs. Scaled down in size and more efficient, such pumps feature an inverter integrated in the electric motor: screw pumps for medium vacuum are suitable for the suction of non-aggressive substances. Their operation is based on the scroll operation principle, without contact; their synchronization is obtained thanks to a pair of gears secluded from the compression chamber. No lubricants such as oil are used for their (oil-free) operation; the two screws never come into contact, and work frictionless. The single-stage construction enables operation without limitation between atmospheric pressure and final vacuum. These pumps stand out for their simplicity, compact size, low noise, yield, and low installed power.