MECHANICAL INTERLOCK FOR PSV INLET BLOCK VALVE

[Iranna Shettar]

DEAR ALL,

CAN ANYONE THROW SOME LIGHT ON THE SUBJECT MATTER, WANT TO UNDERSTAND THE MECHANISM AND ALSO HOW TO CAPTURE IN PIPING DELIVERABLES.


THANKS, AND REGARDS
IRANNA SHETTAR

 

[The Obturator]

This is an often repeated subject. Earlier comments can be found in the Safety Relief Valve Forum Section. Use the search box to find previous posts.

One example from earlier posts is thread1203-479775


*** Per ISO-4126, the generic term
'Safety Valve' is used regardless of application or design ***

*** 'Pressure-relief Valve' is the equivalent ASME/API term ***

 

[LittleInch]

Can you elaborate?

Interlock implies you have two PSVs, one duty, one standby and this is to be able to change from one to the other for testing?

Or a simple Locked open valve on a single PSV?

Also please don't write in ALL CAPITALS. It usually implies you're SHOUTING!!!

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

 

[Iranna Shettar]

Yes i am looking for 1st statement requirement.

 

[LittleInch]

Well it's a mechanical Key system.

It prevents you closing the operational valve before the second one is opened. When the second valve opens it releases a key which you can then use to close the first valve.

Just note it on the MTO or valve spec as being one of a pair of interlocked valves where at least one valve is required to be open at all times.

Talk to some vendors like

https://www.smithflowcontrol.com/

https://www.sofisglobal.com/products/valve-interlocks-smith/

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

 

[Iranna Shettar]

Thank You for your time and clarifications.