Diaphragm Pumps Ltd

NDP25 Air Operated Double Diaphragm (AODD) Pumps are becoming the most common pumps for use when Only Air is available or when pumping solid laden liquids or slurries. NDP25 Diaphragm Pumps have no seals as the diaphragm acts as the barrier between the Liquid side and the drive side of the pump. When the liquid pressure reaches the air pressure, the NDP25 pump reaches a point of balance and stalls without the need for bypasses or overload protection.NDP25 Diaphragm Pumps pump can run dry indefinately and have the ability to self prime to 7 metres or more in some cases. They can handle viscosities up to 20000 Centipoise as standard and some NDP25 models can handle cPs into the 100's of 1000's. NDP25 Pumps are some of the most reliable AOD's in the marketplace, Self Priming, Dry running, Intrinsically safe, these are just a few of the features of NDP25 Diaphragm Pumps. Models include pumps for pumping hygienic products, aggressive chemicals aswell as standard industrial duties. High pressure models are also available for filter press applications or for pumping into closed systems. ATEX regulated NDP25 pumps are offered for Zone 1 environments. NDP25 Pumps and spares are available from Diaphragm Pumps Ltd, Stoke On Trent, England. As one of the largest stockists of pumps and spares in Europe, we hope we can supply all your NDP25 Pump needs.

Yamada NDP-25 Series Pumps

49 USGPM - 1" Port Size

    Port Dimensions
    Intake & Discharge Connections
  • Polypropylene (PPG): 1" Female NPT
  • Kynar® (PVDF): 1" Female NPT
  • Aluminum (ADC-12): 1" Female NPT
  • Stainless Steel (316): 1" Female NPT
  • Cast Iron: 1" Female NPT
    • Air Inlet
  • 3/8" Female NPT (includes ball valve)
    • Air Exhaust
  • 3/4" Female NPT (includes silencer)
  • ANSI Flange also available Consult Yamada.
    • Maximum Liquid Temperature*
    Diaphragm Material / Temperature
  • Neoprene: 180°F (82°C)
  • Buna N: 180°F (82°C)
  • EPDM: 212°F (100°C)
  • Hytrel: 248°F (120°C)
  • Santoprene: 225°F (107°C)
  • Viton: 248°F (120°C)
  • Teflon: (PTFE) 212°F (100°C)

    • *Polypropylene pumps have a maximum liquid temperature of 180°F (82°C) regardless of diaphragm material.

    Kynar pumps have a maximum temperature of 248°F (120°C) when fitted with Hytrel or Viton diaphragms.

    Air Supply Pressure (All Models)
  • 20 to 100 PSI (1.4 to 7 kfg/cm)
    • Discharge Volume Per Cycle
  • Rubber diaphragm: 0.23 gallons (862 cc)
  • PTFE diaphragm: 0.17 gallons (654 cc)
    • Maximum Cycles Per Minute
  • Rubber diaphragm: 210
  • PTFE diaphragm: 210
    • Maximum Size Solid
  • 3/16" (4.8 mm)
    • Maximum Dry Suction Lift
  • Rubber-fitted pump capability: 18-feet
    • Air Motor
  • Standard: Aluminum
  • Optional: Epoxy-coated, Teflon-coated, or Electroless Nickel Plate

    All Polypropylene, Aluminum, Cast Iron, and SS Hytrel fitted pumps include Buna N check balls & o-rings and Santoprene fitted pumps include EPDM check balls & wetted o-rings. Kynar (PVDF) pumps fitted with Santoprene, Hytrel, or Teflon include Teflon check balls & o-rings. Kynar/EPDM fitted pumps include EPDM check balls & o-rings and Viton fitted include Viton balls & o-rings.

Click Here for the NDP20 & NDP25 Maintenance Manual