Pneumatic Solenoid Valves

[g1a1]

Looking for a 3-way, S/S, Normally Closed, 12vdc-low power Pneumatic Solenoid Valves for -40F service. One at a Cv=0.7 min and the other at a Cv=3.00 min. It must exhaust a 2" and 8" (respectively) ball valve equipped with a actuator(port=0.7Cv and 3.00Cv) in 2.0 sec or less. I have tried some off-the-shelf solenoids rated to -40F, but closing times at -40F were too slow. Ambient speeds were OK. I have surfed the web and have made numerous contacts, but have not had any success. I would appreciate any assistance.
Thanks

 

[jsummerfield]

You may want to post in the Control Systems and the Measurement and control instrumentation industry forums.

John

 

[g1a1]

Thanks for the tip

 

[ALEXFV]

Hello:
You could try model SCG327A111 from ASCO Control (Netherlands) It's an special model suited for low temperature. Maybe Cv is around 0.49 (port 1-2) and 0.56 (port 2-3).
Is almost sure that this valve can handle ypu request, but is a special model from ASCO Netherlands.

If need more specs. please write to soporte@calfer.com

 

[israelkk]

The seconds closig time is for the electro-penumatic valve alone or combined with the ball valve?

 

[g1a1]

Closing time includes the solenoid combined with ball valve mounted with actuator.

 

[israelkk]

If so, maybe the ball valve is the problem such as ball friction increase in colder temperatures. Electro-pneumatic Valve on and off time are ususally very short I assume 10 to 100msec only. I will look for the ball valve closing time and the actuator return time. In cold temperatures the gas inside the actuator become more sluggish and need more time to exit the actuator volume. Add to this the option that there is moisture in the actuator volume that might freeze and block the gas exhaust passage too.

 

[g1a1]

A test was performed on the Valve/Actuator assembly only and closing time was under 2 secs. This confirmed that (1) no moisture was enter the system and (2) the Valve/Actuator was capable of cycling shut in the required time.

 

[israelkk]

But, how fast you want the electro-pneumatic valve to be? You didn't give the desired electro-pneumatic valve opening and closing time. Can you clarify how much time it took for the ball valve and the actuator to close and how much time it took for the electro-pneumatic valve to close when the whole system was too slow?

 

[g1a1]

Closing time for the solenoid only was not recorded, just the overall time when the solenoid was energized. We eliminated the issue by using a quick exhaust. That was using a brass Asco Solenoid Valve. Our customer has changed requirements to a S/S which is not offered in the same design as the Brass. It appears the internal pilot sticks at -40F and supply air is exhausted when the solenoid is de-energized. After sufficient time has passed (30sec), the pilot kicks in (warms up ?. Tha solenoid valve is a special from asco rated at -40F, but does not appear to work. Have you any experience with Versa Solenoid valves at -40F?

 

[israelkk]

I would call ASCO. Ihis is a mulfunction valve, maybe the grease or the rubber parts are incorrect and are not compatible for the low temperature. This shouldn't happen unless something in the manufacturing process was faulty. I am not familiar with Versa Solenoid valves but to my knowledge ASCO is a good producer. My experience with valves comes from the aerospace area, I have developed and designed variaty of fast custom ON-OFF electro-pneumatic valves so your post caught my attention.

 

[g1a1]

Thanks for your assistance