NDP-50 Series

Yamada® NDP-50 Series Double Diaphragm Pump

Yamada Trial Pump Program

2" Fluid Port

Yamada® NDP-50 series AODD pumps provide a maximum flow rate of 164 gallons per minute. Pumps are available in aluminum, stainless steel (316), Kynar® (PVDF), groundable acetal, and polypropylene construction.

What separates Yamada from the rest of the pack is our air valve technology. Yamada uses a completely non-lubricated main air valve and independent pilot mechanisms to control the air logic.

As compressed air enters the pump, it is directed via the main air valve to one side or the other, depending upon the starting position of the c-spool.  As the air enters the chamber, it forces the diaphragm outward. This outward momentum forces liquid out of the discharge ball valve and loads the opposite inlet ball valve. As the diaphragm travels outward, the connected diaphragm on the opposite side is pulling the diaphragm inward.

When it travels a full stroke, it will contact the pilot valve, depressing it and breaking the seal to open an exhaust port.

The open port allows the compressed air to the exhaust from the back side of the air valve. The pressure drop produces a shift of the main air valve. This motion simply repeats on the other side.

Options > Ultimate Diaphragms, Abrasion Pads



164 Gallons/Minute
2" Fluid Port (NPT or ANSI Flange)


Intake & Discharge Connections
Polypropylene (PPG)
2" ANSI Flange B16.5 #150
Kynar® (PVDF) 2" ANSI Flange B16.5 #150
Aluminum (ADC-12) 2" ANSI Flange B16.5 #150 (with tapped 2" Female NPT)
Stainless Steel (316) 2" ANSI Flange B16.5 #150 or 2" Female NPT
Cast Iron 2" Female NPT
Air Inlet 3/4" Female NPT (includes ball valve)
Air Exhaust 1" Female NPT (includes silencer)


Diaphragm Maximum Liquid Temperature1
Buna N 180°F (82°C)
Neoprene 180°F (82°C)
Santoprene®(TPO) 180°F (82°C)
EPDM 212°F (100°C)
PTFE 212°F (100°C)
Hytrel® (TPE) 248°F (120°C)
Viton® fluoroelastomer 248°F (120°C)
Ultiimate 212°F (100°C)
*The maximum liquuid temperature for metal and Kynar® fitted pumps is determined by the elastomer (diaphragm material). Polypropylene pumps have a maximum liquid temperature of 180°F (82°C) regardless of diaphragm material. 


Air Supply Pressure (All Models) 20 to 100 PSI (1.4 to 7 kgf/cm²)
Discharge Volume Per Cycle

Rubber diaphragm: 1.12 gallons (4.25 liters)
PTFE diaphragm: 0.69 gallons (2.61 liters)

Maximum Cycles Per Minute

Rubber diaphragm: 146
PTFE diaphragm: 220

Maximum Size Solid 5/16" (8 mm)
Maximum Dry Suction Lift Rubber-fitted pump capability: 19-feet
Air Motor

Aluminum - Metal or Plastic Pumps
Plastic - Plastic Pumps

Optional Coating PTFE-coated


Model # Description
852423 NDP-50BAC
852229 NDP-50BAN
852424 NDP-50BAE
852230 NDP-50BAH
852717 NDP-50BAS
852303 NDP-50BAV
852231 NDP-50BAT
852231-U NDP-50BAU
852425 NDP-50BSC
852232 NDP-50BSN
852426 NDP-50BSE
852233 NDP-50BSH
852718 NDP-50BSS
852304 NDP-50BSV
852234 NDP-50BST
852234-U NDP-50BSU
852647 NDP-50BSC-NPT
852643 NDP-50BSN-NPT
852648 NDP-50BSE-NPT
852644 NDP-50BSH-NPT
852721 NDP-50BSS-NPT
852646 NDP-50BSV-NPT
852645 NDP-50BST-NPT
852645-U NDP-50BSU-NPT
852841 NDP-50BFC
852837 NDP-50BFN
852842 NDP-50BFE
852838 NDP-50BFH
852843 NDP-50BFS
852840 NDP-50BFV
852839 NDP-50BFT
852839-U NDP-50BFU
852427 NDP-50BPC
852235 NDP-50BPN
852428 NDP-50BPE
852236 NDP-50BPH
852719 NDP-50BPS
852305 NDP-50BPV
852237 NDP-50BPT
852237-U NDP-50BPU
854836 NDP-50BPC-PP
854837 NDP-50BPN-PP
854838 NDP-50BPE-PP
854841 NDP-50BPH-PP
854842 NDP-50BPS-PP
854839 NDP-50BPV-PP
854840 NDP-50BPT-PP
854840-U NDP-50BPU-PP
852813 NDP-50BVE
852489 NDP-50BVH
852775 NDP-50BVS
852812 NDP-50BVV
852485 NDP-50BVT
852485-U NDP-50BVU
854848 NDP-50BVE-PP
854851 NDP-50BVH-PP
854852 NDP-50BVS-PP
854849 NDP-50BVV-PP
854850 NDP-50BVT-PP
854850-U NDP-50BVU-PP


:: Aluminum
Dimensions: 17.78" W x 30.70" H
Net Weight: 81.6 lbs. (37 kg)
Shipping Weight: 96.6 lbs.
:: Cast Iron
Dimensions: 17.72" W x 30.56" H
Net Weight: 143 lbs. (65 kg)
Shipping Weight: 158 lbs.
:: Stainless Steel (NPT)
Dimensions: 17.72" W x 30.56" H
Net Weight: 132 lbs. (60 kg)
Shipping Weight: 147 lbs.
:: Stainless Steel (ANSI flange)
Dimensions: 17.72" W x 30.78" H
Net Weight: 132 lbs. (60 kg)
Shipping Weight: 147 lbs.
:: Polypropylene (ANSI flange)
Dimensions: 18.30" W x 32.30" H
Net Weight: 77.2 lbs. (35 kg)
Shipping Weight: 92.2 lbs.
:: Polypropylene-PP (ANSI flange)
Dimensions: 18.30" W x 32.30" H
Net Weight: 81.6 lbs. (37 kg)
Shipping Weight: 96.6 lbs.
:: Kynar (PVDF) (ANSI flange)
Dimensions: 18.19" W x 32.24" H
Net Weight: 90.5 lbs. (41 kg)
Shipping Weight: 105.5 lbs.
:: Kynar-PP (ANSI flange)
Dimensions: 18.18" W x 32.24" H
Net Weight: 94.8 lbs. (43 kg)
Shipping Weight: 109.8 lbs.


Air Motor Kit

K45-AM (metal center body) and K50-AM-PP (plastic center body)

Liquid End Kits
  Aluminum: K50-MC, K50-MN, K50-ME, K50-MH, K50-MS, K50-MV, K50-MT, K50-MU
  Stainless Steel: K50-MC, K50-MN, K50-ME, K50-MH, K50-MS, K50-MV, K50-MT, K50-MU
  Cast Iron: K50-MC, K50-MN, K50-ME, K50-MH, K50-MS, K50-MV, K50-MT, K50-MU
  Polypropylene: K50-PC, K50-PN, K50-PE, K50-PH, K50-PS, K50-PV, K50-PT, K50-PU
  Kynar: K50-VE, K50-VH, K50-VS, K50-VV, K50-VT, K50-VU
Filter / Regulators

FR-5, FR-5A (Auto Drain)


AD-50 Series

Liquid Level Controller




Diaphragm Monitor System


DRy Run Detector


The Yamada Advantage

Yamada Air Powered Double Diaphragm Pumps: Engineered for High Performance. Manufactured for Long Life.

Rugged, Bolted Construction

All Yamada pumps feature bolted construction, which eliminates leaks and simplifies post-maintenance reassembly. Bolted construction is superior to clamp band retainers, which frequently require frustrating, unnecessary leakage rebuilds from misalignment during reassembly.

Outside-Accessible Air Valve

Inspection or maintenance of every Yamada air valve may be performed without removing the pump from service. Outside accessible, making it easy to fix / inspect.

Unified Air Valve Concept

Common-size air valve assemblies reduce parts confusion and inventory.

Pilot Valve

Unique to the Yamada design is an individual modular pilot valve that actuates the air valve. It is depressed slightly by the inner center disk creating a pressure drop at one end of the air valve, allowing shifting to occur. It is maintenance free with no cumbersome snap rings or lubricated dynamic o-rings to replace or repair.

Patented Air Valve Technology

Incorporated in every Yamada Air Powered Double Diaphragm pump

Yamada air valve technology is the heart of the air-powered double diaphragm pump and determines reliability. Yamada holds three patents on its field proven valve and enjoys a superior reputation throughout the industry.

Why Specify an AODD Pump?

  • Handles a wide variety of fluids with high solids content
  • Self Priming
  • Ability to Run Dry
  • Variable flow rate and discharge pressure
  • Portable
  • Simple Installation
  • Dead Head
  • Shear Sensitive
  • Safe Operation
  • Submersible
  • Pumping efficiency remains constant
  • Cannot Overheat
  • High Pressure capabilities
  • No mechanical seals, couplings or motors
  • No pressure relief or bypass needed

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