Where, how and when i must use doub

[maceca]

Where, how and when i must use double check valves (two check valves in serie)?
I ask it because we are using this configuration in several questionable points. Like liquid level control of equipments, connections in headers and stand by equipments.

 

[mk3223]

The double check valves piping setup was to be one of the acceptable mechanism for the system isolations and typically applied in the process system. But through the years, it was gradually replaced in the operation piping system with other more secured mechanism, such as blind, air gapped, etc.. It still uses in the temporary piping clean-up spool in shutdown.
You may want to review the piping systems in the next PHA study of the Ops Unit and discuss the required action to improve the plant safety.

 

[LittleInch]

maceca,

Please don't double post and if you do want to ask a different but related question, include the link to your other post ~See

https://www.eng-tips.com/viewthread.cfm?qid=518443

for much more information about the situation.

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.