Duplex Plunger Pump

Plunger pumps are pumps in which a plunger slides back and forth within a stuffing box, increasing and decreasing the working volume. Such designs are better suited for high pressures as seals are stationary within the pump, as opposed to piston designs where the seal slides within a hollow chamber.A plunger, force cup, plumber's friend or plumber's helper is a tool used to clear blockages in drains and pipes. It consists of a rubber suction cup attached to a stick (shaft) usually made of wood or plastic. A different bellows-like design also exists, usually constructed of plastic.