Abstract: This disclosure relates to a highly durable positive displacement pump capable of dry-priming and pumping of a liquid containing abrasive non-soluble material. The pump assembly comprises an internally pressurized diaphragm assembly secured to a pump bowl and a pump bowl tube. A suction inlet and discharge outlet are located at opposite ends of the pump bowl tube, the inlet and outlet are each configured to receive a valve that limits flow of the liquid to a single direction. The internally pressurized diaphragm assembly comprises an upper diaphragm positioned atop a lower diaphragm wherein a cavity is formed between the diaphragms that is pressurized thereby reducing fatigue failure inducing stresses. Reciprocating axial movement of the internally pressurized diaphragm assembly, produced by a drive means, suctions the liquid in through the suction inlet and then discharges the liquid through the discharge outlet.

Abstract: This disclosure relates to a highly durable positive displacement pump capable of dry-priming and pumping of a liquid containing abrasive non-soluble material. The pump assembly comprises an internally pressurized diaphragm assembly secured to a pump bowl and a pump bowl tube. A suction inlet and discharge outlet are located at opposite ends of the pump bowl tube, the inlet and outlet are each configured to receive a valve that limits flow of the liquid to a single direction. The internally pressurized diaphragm assembly comprises an upper diaphragm positioned atop a lower diaphragm wherein a cavity is formed between the diaphragms that is pressurized thereby reducing fatigue failure inducing stresses. Reciprocating axial movement of the internally pressurized diaphragm assembly, produced by a drive means, suctions the liquid in through the suction inlet and then discharges the liquid through the discharge outlet.