There are very few diaphragm valve parts. The primary component is an elastomeric diaphragm, which is similar to a pinch valve that uses an elastomeric liner. Shut-off in a diaphragm valve results when the diaphragm pushes into the bottom surface of the valve body. However, diaphragm valves feature precise control for regulating flow and pressure drop at various levels.

You will find two basic types of valve designs from a diaphragm valve supplier. Firstly, the weir form is well suited for general purposes, and for applications involving corrosive substances. The straight-through form is good for systems where flow direction reverses, and also for applications involving viscous fluids. These valves seldom clog.

These are some of the important characteristics of diaphragm valves:

1. Diaphragm valves are very clean, ideal for drinking water, pharmaceutical and food applications.

2. Diaphragm valves don't require much maintenance, and it's possible to replace them without dismantling pipe lines.

3. Diaphragm valves have relatively low temperature tolerances(-60 to 450 degrees F) and pressure tolerances (about 300 psi).

Action Steps
The best contacts and resources to help you get it done

Find quality diaphragm valve manufacturers and diaphragm valve distributors

Other types of valves are more widely produced, but there are still plenty of diaphragm valve suppliers. Don't settle for a product that's over-priced or not quite the right fit for the application. A good diaphragm valve supplier has a wide selection, or specializes on a particular application.

I recommend: Asahi America carries a wide variety of diaphragm valves, including electrically or pneumatically actuated models. Gemu is another good company that provides industrial diaphragm valves, as well as sanitary diaphragm valves for food, pharmaceutical and many other applications.

Get clear information about the diaphragm valves you want to purchase

Since there are multiple styles of diaphragm valves, you may want to look at sources that provide a lot of information along with their products. This will help you make good decisions as you buy diaphragm valves.

I recommend: Plast-O-Matic Valves, Inc. manufactures somewhat unique valves that prevent product contact with metal, and their valves are compact. Their website not only contains clear descriptions on specifications, uses and operations of their valves, but also a movie. Top Line Process Equipment Company also provides ample information with their products, including pictures, specs, the advantages of each type of diaphragm valve and online brochures.

Repair or replace your diaphragm valve part

Diaphragm valves seldom leak and they are fairly easy to replace. However, just like any valve, you should pay attention to them. Failing to maintain or replace any valve can result in untimely production shutdowns and other inconveniences.

I recommend: ITT provides online maintenance manuals in multiple languages for their products. Whichever manufacturer you buy from, pay attention to the manufacturer information on temperature and pressure ratings and general maintenance and operation. When it comes time to replace diaphragm valve parts, Sanitary Process Components is a good place to look.

Tips & Tactics

Helpful advice for making the most of this Guide

• •  Diaphragm valves are not good for multi-turn operations.