Blagdon B25 Metallic Diaphragm Pump

  • Max. Capacity 180 l/min

  • Max. Pressure 8.8 bar

  • Max. Viscosity 5,000 cP

  • Temperature Range Limited by elastomers - Up to 180 deg C.

Blagdon B25 Metallic Diaphragm Pump

Metallic Blagdon Air Operated Double Diaphragm Pump for Waste Water applications and more.

High Suction, Atex extreme environment pump. 

Fully Submersible Pump. 

Up to 180 l/min

1" Air Operated Diaphragm Pump

Metallic Construction suitable for "Work-horse" applications
Blagdon Air-Operated Double Diaphragm (AODD) Pumps provide high performance, reliable solutions for your pumping needs. They specialise in extreme condition environments and applications...keeping your process moving both above and below ground. Their AODD pumps have long been recognised as the "workhorse" of the industry for handling difficult liquids at relatively low pressures and flows. The range of applications is virtually limitless!
The pump chambers are alternately filled and emptied by drawing fluid in through a common (suction) inlet, and out through a common (discharge) outlet. The diaphragms in each chamber are linked by a common shaft so that they move backwards and forwards in unison. Compressed air is directed by the air valve alternatively, behind each diaphragm, to power discharge strokes. Pump speed, fluid output and pressure (or head) is controlled by increasing or decreasing the flow of compressed air to the pump.

Common applications:

Vast range of liquids and chemicals
Optional Atex certification available
Low cost, straight forward construction
When electrical power is not available
Noise sensitive areas


Pump type: Air Operated Double Diaphragm Pump
Control: Valve in air inlet (not included) 
Materials: Metallic casing (see options)
Fluid Connections: 1" BSP Female
Max Solid diameter: 3mm
Max Flow rate: 180 litre/min
Displacement: 0.475 litres/stroke
Max Discharge pressure: 7 bar
Air Inlet: 3/8" BSP(F) 
Pump weight: see options list


  • Simple construction, easy to maintain & control
  • 1" Threaded Ports
  • ATEX approved as option - intrinsically safe
  • Reliable, proven pneumatic air valve
  • Strong, robust design
  • Manufactured in Shannon, Ireland


Casing materials: Aluminium/Aluminium (13.5kg), Stainless/Aluminium (22.5kg), Cast Iron/Aluminium (22.5kg). Stainless/ Stainless (32.5kg) 
Internal material options: Nitrile, EPDM, Neoprene, Santoprene, PTFE, Viton (FKM)
Fluid Connection options: 1" BSP (F) Threaded

Like all air operated diaphragm pumps, this pump requires a compressed air source to function.
Need a compressor and pump combo? Check out the compressors in the "Other Products" menu tab.