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SOLUTION PROVIDING ADVANTAGES... Air-Operated Double Diaphragm Pumps

Informed customers select AODD pumps vs. other pump types when challenged with difficult pumping situations including:

• Suspended Solids • Non-Suspended Solids • Line-Size Solids • Abrasive Sludge & Slurries• High Viscosity Fluids • Dry Running • High Suction Lift • Floor Space Restrictions • Corrosive Fluids • Added Costs for Variable Flow Rates • Added Costs for Installation Bypass Lines • Added Costs for Pressure Relief • High Costs Associated with Packing Glands and Mechanical Seals• Loss of Suction (Prime Damage) • Heat Generation • Catastrophic Mechanical Seal Failures • Leakage from Packed Stufï¬�ng Boxes • Insufï¬�cient NPSH (a) Cavitation • Coupling Misalignment• Bearing Lubrication Contamination • Shaft Deflections • Slip • Decreased Volumetric Efï¬�ciency• Bearing/Shaft (load) problems associated with operating below minimum flow • Deadheading

C l a s s i f i c a t i o n o f P u m p T y p e s

D i a p h r a g m ( M e c h a n i c a l ) R e c i p r o c a t i n g P i s t o n P l u n g e r P o s i t i v e D i s p l a c e m e n t V a n e P i s t o n R o t a r y S c r e w G e a r L o b e

Although the AODD pump is a displacement type it is actually a hybrid and de�es strict classi�cation. While its pressure versus

N o n ( S e m i ) P o s i t i v e

P u m p s

D i s p l a c e m e n t D i a p h r a g m ( A O D D )

capacity characteristics resemble those of a centrifugal pump, it is best de�ned as a non (or semi) positive displacement pump. The pumping principle provides 100% ef�ciency at zero flow.

K i n e t i c C e n t r i f u g a l s

AODD pumps are air (or natural gas) operated displacement type pumps which uniquely differ from all other positive displacement pumps. As a result of air pressure acting on the entire surface of the diaphragm, the diaphragm is in a balanced condition while pumping. This measurably extends diaphragm life over that of mechanically operated diaphragm pumps. Because compressed air is limited, the maximum pressure developed by the pump is also safely limited. Thus AODD pumps are appropriately selected for on-demand intermittent requirements. 4 www.warrenrupp.com