Poly Diaphragm Pump DP-282.1-P

3 diaphragms. Through input shaft: 1″ diameter one end, 1-3/8″ 6-spline opposite end. Negative pressure – max: 4.9 ft; intermittent: 9.8 ft.

The DP-282.1-P features new and innovative DuraMax diaphragms. These diaphragms are “pre-deformed” and provide longer life and better performance with a wide range of chemicals. The plastic polymer provides great strength and long-lasting reliability. The diaphragm washer is made of stainless steel to prevent abnormal deformation of the diaphragm and guides it along the piston stroke. The piston crown has a friction-proof form to eliminate wear caused by rubbing.



  • The heads are designed with a patented technology that includes an aluminum die-cast core inside a polypropylene structure offering superior strength.
  • Washers and diaphragm bolts are in 316 stainless steel, an exclusive feature.
  • Die cast crankcase incorporating a new cooling system.
  • New chemically resistant diaphragm material pre-deformed to reduce the amount of deflection, increasing diaphragm life. The diaphragm material is compatible with most of the corrosive chemicals on the market today.
  • A short crankshaft stroke means the longest life possible.
  • New connecting rods in special bronze alloy offer economical and trouble free service.
  • 316 stainless steel inlet and outlet check valves.


Model Max Flow GPM Max Pres. PSI Max Speed RPM Max Power HP Max Temp. ° F Suct. Hose Diam. Disch. Hose Diam. Weight LB Lube Oil
DP-282.1-P 28.2 218 550 4.1 140° F 1-1/2″ Hose 1″ NPT 41.8 30 SAE


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