How to Service Seals on Plunger Pumps | Video

In this video, CAT Pumps® demonstrates how to service, repair, and replace the seals on the 650 or 660 series plunger pumps. This includes proper removal of the manifold, removal of the seals, inspection and servicing of the seals, and reassembly of the pump.

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Plunger pumps, a type of positive displacement pump, work by expanding and contracting a cavity in a cylindrical chamber using a plunger rod. As the rod contracts the cavity, fluid is expelled through a discharge valve. The rod is then backed off of the cavity, closing the discharge valve and opening an inlet valve, which floods the cavity with fluid again.

CAT PUMPS® offers several different designs of plunger pump, all of which share the same basic concept. A direct flow pump, described above, a flushing port pump, which adds an inlet and outlet valve to move a flushing liquid through the pump, and a "Superflow" pump that includes a flow-through ceramic plunger.