Best Diaphragm Pumps

Learn more about the best diaphragm pumps on the market with rankings, prices, FAQs and other important information.

Updated on July 16th, 2019

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A diaphragm pump is a motorized pump that expels liquid by pushing it through a series of valves. Diaphragm pumps can be used to displace water or other liquids in industrial settings.

15 Best Diaphragm Pumps:

Our Rank

Model

List Price

1.

Welch 2014B-01 1 Ph DryFast Collegiate Diaphragm Pump

$1,547.69

2.

Welch 2037B-01 1 Ph DryFast Diaphragm Pump

$1,959.06

3.

Alemite 8322 1/2" Diaphragm Poly Pump, Buna Diaphragm Material

$499.99

4.

Alemite 8301 1/4" Diaphragm Poly Pump Teflon Diaphragm Material

$362.12

5.

Welch 2019B-01 Diaphragm Pump - Vacuum Filtration

$850.00

6.

Welch 2034B-01 DryFast 25 l/min 1 Phase Diaphragm PTFE Pump

$2,166.77

7.

Ace Glass 13070-07 Liquid Pump, PTFE Diaphragm, Analog

$1,264.00

8.

Ace Glass 14101-04 Vacuum Pump, PTFE Diaphragm, 75torr, 15psig

$754.00

9.

Welch 411721-01 1 Phase Standard Duty Diaphragm Pump

$2,100.44

10.

AR North America AR135BP-SP 1" 33.8 GPM 290 PSI Low Pressure Diaphragm Pump

$970.00

11.

Alemite 8323 1" Diaphragm Aluminum Pump, Buna Diaphragm Material

$479.99

12.

Alemite 8325 1" Diaphragm Pump, Buna Diaphragm Material

$706.35

13.

Alemite 8324 1-1/2" Diaphragm Aluminum Pump, Buna Diaphragm Material

$772.91

14.

Alemite 8322-A 1/2" Diaphragm Aluminum Pump, Buna Diaphragm Material

$688.79

15.

Alemite 8322-C 1/2" Diaphragm Poly Pump, Teflon Diaphragm Material

$684.46

FAQs:

What is a diaphragm water pump?

A diaphragm or membrane made of a rubber or plastic material flexes to lower the pressure inside the pump, drawing in fluid. The diaphragm then flexes back to pump out the water. A check valve will keep the liquid from flowing back into the pump.

Learn more about diaphragm pumps.

How does a pneumatic diaphragm pump work?

A pneumatic diaphragm pump uses compressed air in a vacuum to draw liquid in and push it through the diaphragm to the other end of the pump.

Read our guide to diaphragm pumps.

Can diaphragm pumps run dry?

Air operated double diaphragm pumps can be used while dry without causing any damage, but other types may require liquid for operation.

For more information, read our detailed guide.

Are diaphragm pumps reversible?

You can find diaphragm pumps that are reversible and some that are not.

Are diaphragm pumps self priming?

The casing of a centrifugal pump should be primed before you turn it on. However, most positive displacement pumps are self-priming, so they do not need to be primed before each use. Always check the user manual before use.

Where are diaphragm pumps used?

Diaphragm pumps are used in practically every industry that requires fluid transfers, particularly dewatering, water removal, filling, dispensing, or metering.

How do you troubleshoot a diaphragm pump?

  1. Check the inlet air line size and pressure.
  2. Inspect for muffler icing and restrictions.
  3. Inspect sealing surfaces for leakage.
  4. Ensure you have the proper tubing and piping size.
  5. Slow the pump down to prime it.
  6. Clear any fluid line restrictions.

How does a diaphragm pump work?

In simplest terms, a diaphragm pump uses air displacement to draw liquid into a chamber, which it then expels through the contraction of the diaphragm. This is why diaphragm pumps are sometimes called air diaphragm pumps.

What is a double diaphragm pump?

A double diaphragm pump has two diaphragms that move back and forth to create fluid motion. An air valve connects the diaphragms to create the displacement.

Best Diaphragm Pumps

What are the best diaphragm pumps?:

  • Welch, 2014B-01 1 Ph DryFast Collegiate Diaphragm Pump.
  • Welch, 2037B-01 1 Ph DryFast Diaphragm Pump.
  • Alemite, 8322 1/2" Diaphragm Poly Pump, Buna Diaphragm Material.
  • Alemite, 8301 1/4" Diaphragm Poly Pump, Teflon Diaphragm Material
  • Welch, 2019B-01 Diaphragm Pump - Vacuum Filtration

See our diaphragm pump guide.

What are small diaphragm pumps used for?

Small diaphragm pumps can be used for everything from removing dirty water, processing harmful chemicals, moving thick fluids, and moving oils from one container to another.