Rotary vane: Rotary vane pumps are comprised of a series of vanes that are mounted to a rotor that turns in the cavity. As the vanes rotate, centrifugal power extends them from their individual slots, forming compression cellular material that get bigger to draw air in from the intake and smaller to push atmosphere out the exhaust.
Articulated piston: An articulated piston commercial vacuum pump functions in a manner similar to that of a car engine. As the piston moves downward in the cylinder, air is used through the consumption valve. Industrial Vacuum Pumps During the piston’s upward stroke, the air flow is permitted to escape via an exhaust valve. Two spring-backed piston bands are accustomed to seal the piston to the cylinder.
Screw: Rotary screw pumnps include two parallel rotary screws in the pump casing. The screws are synchronized to carefully turn in opposing directions, which in turn causes the compression action that occurs. The gas is compressed in direction of the pump’s discharge slot.
Liquid ring: Liquid ring pumps also operate via positive displacement. During procedure, the pump’s impeller rotates in the pump casing. A rotating liquid band after that seals the impeller 
and its blades. Liquid can be sucked into the compression chamber to keep carefully the ring steady. Conveyed gas can be compressed during each impeller revolution.
Claw: Claw vacuum pumps consist of two rotors that are extremely close but usually do not are exposed to one another during rotation. As the rotors convert they actually enlarge the area between them to draw in air, then because they rotate around, physically reduce the space between them to compress the surroundings out from the chamber.