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How to choose the right diaphragm valve for optimal performance and durability

The diaphragm valve is a crucial component in the process industry and is used to regulate the flow of gases and liquids. To ensure the best possible performance and long service life, it is important to choose the right diaphragm valve for your specific application. In this article, we will explore what a diaphragm valve is, its function, advantages over other valve types, and how to select and maintain it for optimal efficiency.

What is a diaphragm valve and how does it work?

A diaphragm valve has a flexible diaphragm that moves against a "lug" in the valve body. The spindle can be operated mechanically by a handwheel or pneumatically or electrically. The pneumatic variants come in three versions: spring closing, spring opening or double acting. Spring closing is used for "fail-safe close" and spring opening for "fail-safe open", which means that the valve closes or opens itself in the event of a loss of electricity or air.

Advantages of diaphragm valves

Diaphragm valves offer outstanding efficiency and versatility, especially when precise flow control is essential. These valves are easy to adjust to regulate flow, making them ideal for flow control in a variety of applications.

Use in the process industry

Asahi's diaphragm valves are suitable for most chemicals in the process industry and are available in materials such as PP, PVC, PVDF, EL-PVDF, as well as diaphragms in both EPDM and PTFE, EL-PTFE for best chemical resistance. Their use ranges over various applications such as sulphuric acid, hydrochloric acid, ferric chloride, lye, pickling baths, hydrofluoric acid, nitric acid and quench fluids.

Installation and maintenance

Diaphragm valves are supplied with flanged connections for easy insertion into the pipework. Alternatively, they can be supplied with threaded ends or ends for socket or butt welding, depending on the requirements of the piping system. Maintenance is minimal, and the only thing that needs to be done is to replace the diaphragm, which is easily done by removing the top of the valve. How often this needs to be done depends on factors such as pressure, temperature and type of media.

How to choose the right diaphragm valve

To ensure you choose the right diaphragm valve for your application, you need to know what medium, pressure and temperature the valve will operate under. Then, the optimal material for both the valve and the diaphragm is determined based on these factors.

Contact Lyma to explore our range of diaphragm valves and receive customised recommendations to suit your specific process industry needs.