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JN Series (1-11 gph) Diaphragm Metering Pumps

Quick Specs

JN Series Diaphragm Metering Pump
JN Series Diaphragm Metering Pump
  • Accuracy: Metering accuracy of +/-1%. Won’t fluctuate over time.
  • Flow: 6 models ranging from 1-11 gallons per hour
  • Pressure: up to 250 psi
  • We use standard motors! 56C Frame – 1/3 HP - 60 Hz
Options: Inverter Duty, Washdown Duty, Explosion Proof, 50 Hz, 3 Phase, Mill & Chem Duty
  • Simplex, Duplex, and Triplex options (number of pumping heads)

These simple, rugged, accurate pumps are used in many industrial plants for injecting a controlled flow of highly reactive liquids. Heavy duty industrial grade construction means those little pumps will deliver many years of trouble free 24-7-365 pumping.


  • JN Series Pumps are designed for especially low rates. Double ball checks with Teflon valve seats assure ±1% steady slate repeatable accuracy over a 10:1 turndown range.
  • Manual output control knob is located on top of the pump for easy access.
  • Automatic pump output control is available for pumps equipped with a variable speed motor.
  • Industrial grade worm gear reducer is permanently lubricated and C face mounted to the motor. Precision internal pump parts run in an oil bath for extended service life. No external lubrication required.}
  • Double diaphragm option is available for superior protection from dangerous liquids.
  • When equipped with the proper materials the JN Series pumps are excellent for pumping dangerous liquids such as acids, caustics and solvents.
  • Tough fabric reinforced rubber diaphragms protect the drive train from the pumped liquid. The short .090" stroke with 2" diameter piston increased diaphragm life by reducing fatigue.

JN Series Pumps, Simplex (One Pumping Head)

Model No. Max GPH (L) per head Max PSI Strokes per minute HP Piping NPT
JN101A 1(3.8) 250 22 1/3 1/4"
JN102A 2(7.6) 250 44 1/3 1/4"
JN104A 4(15.1) 250 88 1/3 1/4"
JN105A 5(18.9) 250 115 1/3 1/4"
JN107A 7(26.5) 250 172 1/3 1/4"
JN111A 11(42) 250 230 1/3 1/4"

JN Series Pumps, Duplex (Two Pumping Head)

Model No. Max GPH (L) per head Max PSI Strokes per minute HP Piping NPT
JN201A 1(3.8) 250 22 1/3 1/4"
JN202A 2(7.6) 250 44 1/3 1/4"
JN204A 4(15.1) 250 88 1/3 1/4"
JN205A 5(18.9) 250 115 1/3 1/4"
JN207A 7(26.5) 250 172 1/3 1/4"
JN211A 11(42) 250 230 1/3 1/4"

Wetted end materials to resist corrosion and abrasion

Solution head and valve bodies Diaphragm Backup Diaphragm Valve balls Valve seats
PVC Neoprene Neoprene 316 SS Teflon
Teflon/Kynar Teflon Faced   Ceramic  
316 SS Hypalon Hypalon Hastelloy C  
  Viton Viton Teflon  

JN Series Literature

Madden Metering Pump Selection Guide

For the cleanest and easiest way to inquire about a Madden metering pump, download this fillable pump selection guide, fill it out, and upload it through the RFQ section of our website. We take pride in responding promptly!
Metering Pump Selection Guide

To learn more about our JN Series diaphragm metering pumps, click here to contact us.
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Celebrating 65 years of business

Madden Manufacturing has been designing and producing industrial steam equipment and diaphragm metering pumps for over 65 years now. We take great pride in the fact that our simple, rugged designs have been around since 1952 with only a few changes since.

With our smaller, family owned company, you can always expect responsive customer service and to receive some of the most durable products on the market. Thank you to all our distributors, reps and end users for helping us thrive for the past 65 years. 

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