Un-balanced Vane pump The vane-type positive displacement pump is the simplest has a circular rotating inside a larger circular cavity.
Reciprocating pumps use pistons that move up and down, while rotary pumps use plungers that rotate around a fixed point.
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The rotating element develops a liquid seal with the pump casing and creates suction at the pump inlet.
Pumps for these applications are usually or units, and they may use either , which incorporate seals that move with them, or , which move through stationary seals.
Single Acting Reciprocating Pump: In this case, the suction force moves in one direction of the piston and exits in the other direction.