Solenoid Valves

Solenoid Valves for Very Aggressive and Corrosive Media

PVC solenoid valve 160 seriesSolenoid Valves are available for very aggressive media such as strong acids, alkali's for dosing and chemical processing systems. However users need to be very aware of the solenoid valve materials of construction and their chemical compatibility. Headaches will arise when you consider that even a general purpose stainless steel or plastic solenoid valve will have typically have other internal parts that will come into contact with the media being controlled such as 430F armature (the magnetic bit within the core tube), 304 stainless steel core tube (the bit the electro magnet or solenoid coil fits over) and internal AISI302 stainless steel springs and clips which many aggressive chemicals will attack and corrode causing the valve to fail.

You can See our article onchemical compatibilityfor more information and guide to help, but we would strongly suggest you seek advise from your solenoid valve supplier in advance and even check with your chemical supplier for approved materials of construction, which is especially helpful when dealing with Branded chemicals comprised of a varied range of unknown aggressive chemical solutions at various dilutions.

How can I simplify the choice of solenoid valve for aggressive and corrosive media?

PTFE solenoid Valves for acid and aggressive mediaThere is a range of Solenoid valves available with a dry armature or isolating diaphragm design, that only allows the controlled media to contact the valve body and seal material isolating the armature, core tube and springs. With media is prevented and isolated from contact with the armature assembly, core tube and other internal parts this radically reduces the chemical compatibility risks as only the solenoid valve body and seal need to be addressed. Typically PTFE solenoid valves will have PTFE body with PTFE seal and as standard will have an isolating diaphragm and as PTFE has great resistance to most aggressive and corrosive chemicals users can feel safe in the knowledge that this type of solenoid valve will resist chemical attack. However keep in mind that the media must be clean and free from any debris as PTFE has poor elastomer properties, and small particles can reduce sealing.

An alternative to a PTFE solenoid valve would be a PVC, PVDF or Nylon bodied solenoid valve, again with this isolating diaphragm and these are typically less expensive than PTFE but will require careful chemical compatibility checks and are typically available with EPDM, Viton and PTFE sealing.

Aggressive media applications can be quite difficult to control when using solenoid valves, one option considered by engineers is to use actuated ball valves but these are typically large, heavy, more expensive and slow acting in comparison.

Keep in mind even when using a dry armature or isolating diaphragm solenoid valve users,  design or maintenance engineers will still need to choose a chemically compatible solenoid valve body material and sealing material. The good news is that there is a full range of PVC, PP, Nylon and PTFE solenoid valves specifically designed for very aggressive media applications.

Read more about valves for acids and alkali applications here...

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