what control and noncontrol valve in subsea wells

[a_m_shiha]

I have specification for sud sea wells said"all actuated valves ,except control valve,shall be hydraulic actuated"

and when I saw the topside P&ID I couldn't realize the different because I found shutdown valves instrument air actuated and others are hydraulic actuated.

How can I to distinguish between control and non control valve?

[13392017]

Hi Shiha,
i try to answer your question. However, it's very difficult. There is a missing information.

Just for your information, All subsea valves will be actuated using hydraulic as driving force. But, recently a few of subsea equipment vendor invent new design that using electric actuated valve.
If you have API 17A, perhaps you will know what is subsea valve, the method to control it etc.

I think, what your subsea spec say about control valve is Directional control valve in subse control module. This DCV usually controlled by pulsed electric signal.