2 Way Air Pilot Operated Valves

What is pilot operated?

Pilot operation is the main force required to open the valve is provided by the media pressure. The pilot can be very small as it only controls the flow of a small diameter impulse line that allows the fluid to open the main diaphragm or piston.

What does 2 way mean?

2 Way or 2 port air operated valves refer to the line connections in that there is a single inlet and outlet which makes them ideal for flow isolation. For most of these valves, the flow direction through the valve must be from the inlet to the outlet as reverse flow will cause the valves to fail or operate unreliably.

Depending on the model, 2 way pilot operated valves are used with liquid or gaseous media and can incorporate many varieties of options:

  • Functional – normally open or normally closed
  • Feedback – limit switches, visual position indicators
  • Various elastomers for compatibility with a wide range of gases and liquids 

Normally closed or normally open?

In valve terms:

  • Normally closed means that the valve is shut and fluid cannot flow from the inlet to the outlet. When the pilot pressure is applied, the internal valve parts move and the media flows from inlet to the outlet, as long as the pressure is higher at the inlet.
  • Normally open means that the valve is open and fluid flows from the inlet to the outlet when the pressure at the inlet is higher than the outlet. When pneumatic pressure is applied to the pilot, the internal valve parts move and the valve will close.

Most air operated valves will only stay in the applied pilot pressure position while the pilot pressure exists. They will revert to the rest position as soon as pilot pressure is removed.

View 2 Way Pilot Operated Valves

M22 Normally Closed 0-80bar

M23 Normally Open 0-80bar

M65 Normally Closed 0.2-16bar

M Series Overview Two, Three & Five Way

VPB 2/2 Normally Closed G1/2", G1", G1.5" 0-50bar

YCP Stainless Steel Angle Seat Piston 0-16bar

SX90 Normally Closed Angle Seat Piston 0-10bar

SX91 Normally Open Angle Seat Piston 0-10bar

Not sure which valve or measurement solution is best?
Use our experience to guide you...

For a deeper understanding of which valve or instrument would be best for you please call or email us now so that we can save you time and ensure you can make a truly objective decision for your company.

Contact Us

Get in Touch

+44 (0) 1443 772500 / 02922 780798

Red Dragon Limited T/A
Measure Monitor Control
Unit 15 Abergorki Industrial
Ynyswen Road
South Wales
CF42 6DL
United Kingdom
EORI: GB791056521000

Got a Question?

Need assistance with a product or an enquiry? Fill in the form below and we will get in touch with you as soon as possible:

The contact form requires that you configure reCAPTCHA in the site configuration.

The contact form requires that you select an email template.