Diaphragm Pump Parts Breakdown

Diaphragm pumps take on the role of heavy-duty jobs of moving liquids, using a diaphragm that expands and contracts to move fluids and even solids. They’ll push abrasive materials and sludge as well. Those in agriculture, construction, emergency applications, and industrial processing are the ones who use these pumps most often. That’s why, when a component wears out on it, it’s imperative that it’s repaired quickly and efficiently to ensure production can continue in a timely manner.

How a Diaphragm Works

Before you purchase a CH&E diaphragm replacement or any other brand, it’s helpful to understand how a diaphragm works.

To put it simply, this pump pulls the liquid or solids in one side and pushes them out the other to transport it effectively. When the diaphragm pulls back, it pulses inward, which creates an empty space to decrease pressure. This works in a natural, science-backed way because fluid will naturally flow from high pressure to low pressure, sucking the liquid outside the pump into the chamber. A one-way inlet check valve will then open and fluid can enter.

The diaphragm will then bend the other way, which means it moves forward. It’ll reduce the space inside the chamber. Pressure is then increased, and any fluid or other material is squeezed out. At this point, all the pressure will open the outlet check valve. The material can then exit through the discharge port. The inlet valve will then close, preventing the material from reentering.

Signs Something Is Wrong with Your Diaphragm

If you’re looking to see if it’s time for replacement, these are some signs to look for:

Loss of Suction

One of the most common signs a diaphragm is failing or has failed is that it’s losing or has lost its suction. As a result, it won’t take in material as it has. This tends to happen when the diaphragm has been overstretched or has a crack or tear. When it’s overstretched, it’s not able to expand and contract as it once did. And cracks or tears will prevent pressure from building.

Reduced Discharge Pressure

The diaphragm may thin, wear over time, or become damaged, hindering it from sealing as it should and continuing to move material through it. As a result, the discharge pressure may be lower than normal. It then can’t operate as efficiently as it should.

Problems with Flow

No matter the type of diaphragm, you may have issues with flow when something is wrong with it. For instance, you might have debris that gets stuck in it frequently because it’s not pumping as thoroughly as it once did. The flow rates may vary at times, or you might notice the flow rate is weak. You could also notice it’s pulsing or surging while the device is in operation.

Leaking Fluid

Whether you’re performing a routine inspection on your diaphragm or just happen to see it’s leaking, that’s sometimes a sign of failure. Cracks, excessive wear, and punctures can all allow fluid to leak out, and these tend to happen over time as the diaphragm wears.

Stretching, Tears, or Cracks

As the diaphragm constantly expands and contracts, it can be stretched beyond its limits. And, in some cases, it’s just overuse that causes it to wear out. You may then see the diaphragm has visible cracks or tears. It may then leak or have problems with suction.

Strange Noises

You get used to the noise a diaphragm makes while it’s running. It is generally a soft, consistent noise that becomes almost like background noise to you. However, if it’s suddenly squeaking, slapping, or rattling, it’s indicating it’s not moving properly. You may have a misalignment, a worn diaphragm, or loose components.

The Diaphragm Parts You Should Know

While each component fails for a different reason, frequency, and average duration of use, these are the main components of your diaphragm:

The Diaphragm Itself

As you’re looking for a CH&E diaphragm replacement or for any other make, know that the diaphragm is the main component. Typically, this component consists of a chemical-resistant material, such as rubber or Santoprene. Over time, this part can easily wear out as it’s stretching and suctioning repeatedly.

Pump Chamber/Housing

The pumping action happens in the pump chamber. This part holds the fluid briefly while the diaphragm moves. Typically, it consists of a metal like aluminum or stainless steel. This part is designed to withstand pressure and resist corrosion, but being exposed to harsh substances or being exposed to incompatible chemicals can break it down. It could also develop cracks, stress fractures, or warping.

Inlet (Suction Valve)

The inlet valve is what lets fluid go into the pump chamber. It either has a flap, spring-loaded, or ball valve. Whenever the diaphragm pulls back, it automatically opens. On the other hand, when the diaphragm moves forward, it closes.

Outlet (Discharge) Valve

The outlet valve is responsible for controlling the fluid when it exits the chamber, preventing backflow. It’s made to handle different temperatures, chemicals with different properties, and pressure, but it can still wear out over time.

Air Distribution System/ Air Chamber

An air-operated double diaphragm (AODD) pump needs compressed air for the pumping action. This has an air valve, pilot valves, and a spool/shuttle mechanism that can all go bad. That isn’t taking into account that dirt and moisture could lead to the air supply staling.

Manifold

The manifold is the connection between the outlet and inlet ports. It serves the purpose of channeling fluid through the pump. It can handle abrasive or thick liquids, but it can crack, warp, erode, or become blocked.

Shaft/ Connecting Rod

If you have a double-diaphragm pump, it has a common rod that connects them. Whenever air pressure pushes forward, the rod pulls the other one back. It needs to be aligned perfectly and rigid. If not, it could wear out sooner than it should or make noise or vibrate.

Outer Casing

The pump has an outer casing that protects the internal components. It also provides structure. It’s manufactured with being able to withstand temperature extremes, chemicals, dirt, and liquid, but it can still fail.

Gaskets and Seals

The gaskets and seals make sure all connections are water- and airtight. They help the pump maintain pressure and ensure it operates optimally and are generally made from Viton or another similar material. These can fail and lead to leaks. Depending on the waste, it can be an environmental hazard.

Check Valves

Your diaphragm has check valves that keep the fluid flowing in the right direction. Wear and tear, as well as debris accumulation, can cause them to fail.

A Wacker, AMT, or CH&E diaphragm replacement might be what you need to fix your pump. However, keep in mind that there are other components involved that can also fail.

Diaphragm Pump Parts Breakdown: Replacement Diaphragms for Wacker, AMT and CH&E Pumps was last modified: December 8th, 2025 by Billy Guteng

Written by Billy Guteng. December 8, 2025

Billy is a content writer for Kukun. He was born in France, and has lived in multiple cities around the world ever since. He loves art, design and architecture as well as construction and real estate.