Solenoid Valves

Solenoid Valve Controlled Media Considerations

Solenoid Valves are designed to work according to specific media, function, pressure and temperature parameters. Making sure you have the correct solenoid valve according to the media being controlled will prevent costly machine down time, production delays and allow a maintenance trouble free solenoid valve control.  

Air & Inert Gases

Compressed Air and other inert Gases such as Argon, Helium, Nitrogen and Carbon Dioxide. These inert non aggressive gases can be controlled with standard Brass solenoid valves with NBR seals as these gases at ambient temperature are will not corrode the standard materials of construction.   

Natural Gas

Natural Gas, Town gas or LPG (Liquid Petroleum Gas) normally require an EN161 Gas Board approved solenoid valve that is designed to offer good sealing capabilities, high flow for low pressure systems and have been approved specifically for Gas Systems. 

Light Oil

Light Oil under 50 CST (Centistokes) can be used on most standard brass solenoid valves but attention needs to be given to the seal material compatibility. Normally FKM would be recommended however it is good practise to check with the oil supplier. Some solenoid valves require a viscosity under 40 CST and consideration needs to be given to working temperatures of the oil. Hot oil will require specialist solenoid valve and cold oil becomes thicker and may prevent a solenoid valve from functioning correctly.

Steam

Steam solenoid valves weather Brass, Bronze or Stainless Steel are normally fitted with PTFE seals to resist the aggressive nature of steam up to 200 centigrade. EPDM can also be used for low pressure steam applications up to 150 centigrade but as these are normally less expensive elastomer seal offering better sealing they are not normally the best long term solution. Steam solenoid valves are also fitted with High Temperature Class H (180 C rated) or class N (200 C Rated) coils as opposed to the industry standard Class F (155 C Rated).

Thick Liquids

Thick viscous liquids such as heavy oils, greases, syrups, glutinous media are not suitable for most solenoid valves which are limited to a viscosity of 40 or 50 CST (Centistokes). Specialist coaxial solenoid valves and air operated angle seat piston valves hand handle thick liquids up to 600 CST.  

Vacuum

Solenoid valves are readily available that are suitable for vacuum, low pressure, gravity fed and closed loop systems. These assisted lift - hung diaphragm and direct acting solenoid valves do not require a differential pressure to operate and although normally more expensive than servo / pressure assisted are ideal for vacuum applications.

Water

Water or General Purpose solenoid valves normally of Brass Construction with NBR (Nitrile Buna Rubber) seals are ideal for ambient temperature mains water applications. However these are not suitable for Pure Water, Demin Water and RO water which require a more specialised solenoid control valve.

Slightly Aggressive Media

Solenoid Valves for Slightly Aggressive media such as Pure / Demin / RO Water, Slight Acid or Alkali is normally better suited to either Stainless Steel or Plastic Solenoid Valves. Attention must be given to the seal material and solenoid valve other materials of construction.  

Very Aggressive Media

Solenoid Valves are available for very aggressive media such as Hydrogen Di-Sulphide, Strong Acids and Alkalis etc which utilise a dry armature design which only allows the controlled media to contact the valve body and seal. The core tube (Normally AISI 304),  the armature (Normally AISI430F) and springs (AISI 302 + 303) are sealed and kept dry from the aggressive media.

 

Articles By Category

A catalouge of articles covering all aspects of solenoid valves