API - 614 1

[massunpcao]

On API-614 (Lubrication, Shaft-Sealing, and Control-Oil Systems and Auxiliaries for Petroleum, Chemical and Gas Industry Services), item 6.4.9.5 says "Control valve(s) may be either DIRECT-ACTING or pneumatically-operated.".
1 - What is a direct-acting valve? Is is the same as a self-regulated valve?

M Assunpcao

 

[jsummerfield]

Direct acting control valves could be the self-contained pressure regulators, temperature regulators using filled systems or lever-operated level control valves.

John

 

[tiffy023]

Quite a confusing quote as pneumatic valves can be direct or reverse acting.

From this quote i would say that direct acting is a valve that's hydraulic/electrical/mechanically actuated.