Solenoid Valve? Area Adjustment?

[hanson]

Hi all.
I am now looking for a valve whose opening can be quite accurately controlled.
The size of the opening shall be quite small, around 3mm - 1cm?
I am wondering if you know any valve that may suit my usage?
Can the opening of a solenoid valve be adjusted using electric signal?

 

[stewartcs]

I've never seen a solenoid valve that is variable. Sounds like you need some type of servo or proportional control valve.

 

[FredGarvin]

Asco has a proportional valve, the SD8202 series. I can't vouch for its cost or accuracy although the set up looks extremely easy. Their orifice sizes range all the way down to 3/64"

http://www.lesman.com/unleashd/catalog/valves/valves_posiflow.html

 

[Integral]

Do you need to change the flow rate remotely?

Generally you will find a flow control (needle valve) in line with a solenoid, the solenoid turns the flow on and off while the needle valve controls the flow rate. The flow rate is usually adjusted by hand, though I am sure that there are automated solutions, they will be expensive.

 

[FredGarvin]

Companies like Bauman make a nice actuated needle valve that uses dome loaded air to control the position of the pintle. They are pricey on comparison to solenoid valves, but they are cheap when compared to automated valves in general. Plus, you do get better flow characteristics from a needle valve.