Solenoid Valve Install On the Control Valve

Well, that would depend on

1. what the control valve is supposed to be doing
2. its configuration
3. what the solenoid valve is supposed to be doing
4. the port configuration on the solenoid valve
5. the interconnection with these valves and the control system

none of which has been shared with the forum.

What does the Control Philosophy document have to say about the control valve, the solenoid valve, their interconnection with the control system and how it is all supposed to operate? After all, there is a Control Philosophy document, isn't there?

I don't know this particular valve at all, but generally:

The solenoid valve controls air flow to or from the actuator. (1) it will allow air to the actuator to operate the valve, or (2) it will allow the actuator to vent/ exhaust air so that valve will go to it's normal (open/closed) position....this is called the fail safe position ie if the air supply fails the valve returns to it's safe position.

The valve configuration (angle valve) is not significant.

You need to know if the valve is NO/NC, and if the actuator is spring-loaded. The air must be connected to the side of the actuator that opposes the spring direction.

You need to confirm what the air pressure to the actuator supposed to be. I note the air pressure regulator on the drawing, but that supply may be for the valve positioner, which may be too low a pressure for actuator air.

I have to jump in with PW on this one. I am a bit confused as to the term "Solenoid Valve" when all the valves in the Diagram are what appear to be proportional. Solenoids are generally single duty....on/off.

Is the solenoid valve a safety device for the entire system?

What is controlling the solenoid valve?

Lots of questions as to why you are going to a solenoid valve rather than what is in the schematic need to be answered before there is and answer.

Liew did you contact the Valtek rep ?

Hello Liew 22

It looks like a Spring Piston actuator in your Drawing but the positioner is double acting and giving input to both close and open the actuator, SO it could be that the sping requires help and is not capable of closing/opening the actuator alone ?

i see a three way valve for input to the actuator bottom and top points what kind of valve is this is this a manual valve.

from what is see the two pnuematic valves will remove the air from the actuator cylinder in case the signal fails ( that is the air supply fails) this makes the valve to go to fail safe position.

So whatever that fail safe position is achived only by cutting the signal so it only make sense to me to put the solenoid valve just after the airset filter regulator so you can by DCS/ PLC control the valve oneshot to the failsafe position in case of any issue/sd requirement,

This is just based on the Drawing provided and the valve types and the already existing pnuematic 3 way valves. you might be interested in discussing this matter with the process engineers or the control engineer as to what they desire to achieve by putting a solenoid valve.

Once you have done this you will have a more clear picture- regarding the purpose of yours introducing a sol valve.

Best regards

Naveen Menon