Overpressure Protection By System Design

[alex2010]

I would like to know if the requirements ASME Sec VIII, Div 1, Subsection UG-140 (Overpressure Protection By System Design) would apply to B31.1 and B31.3 designed system that do not have safety valves installed for overpressure protection?

I have read both codes and neither one mentions the use of UG-140.

Thank you.

 

[BigInch]

You should have a look at this one,

http://www.eng-tips.com/viewthread.cfm?qid=231963&page=14

We are more connected to everyone in the world than we've ever been before, except to the person sitting next to us. Lisa Gansky

 

[Korichnevijgigant]

Are you protecting a vessel or just components and pipe?

 

[alex2010]

I am protecting components and associated piping.

I read the suggested topic but could not draw a conclusion from it.

 

[BigInch]

You're nuclear. What kind of chance do you want to give us to survive?

We are more connected to everyone in the world than we've ever been before, except to the person sitting next to us. Lisa Gansky

 

[alex2010]

haha luckly this particular piping system is for an experiment and is not nuclear

 

[MJCronin]

Alex,

Generally speaking, a piping system is protected from pressure when the MAOP is selected by the owner and all system components(ie. piping flanges, valves etc) are properly selected for that service.

This is most commonly done by developing and using a piping "line spec" for the service.

When the system pressure does not exceed that of the line spec, no relief devices are required.

Exceptions to this general rule exists with fluids that change state (vaporize) within the piping system and thereby can increase pressure if contained between valves. Chlorine would be one example. A chlorine piping system subject to warming must have relief valves on piping segments that can be "blocked-in"

-MJC

 

[CodeBum]

As a member of B31.3, I can tell you we don't ref UG-140 specifically, but B31.3 adopts the philosophy of UG-140, in that you can protect a piping system by design (para 301.2.2). There are no specific documentation requirements in B31.3 to protect a system by design as there are using UG-140 with pressure vessels. B31.3 is performance based meaning it does not tell you how to design for containment, but if it fails, the finger is pointed back at the designer.

If you'd like an official position from B31.3 look at App Z. It outlines how to submit an inquiry to the committee.

All I can say about B31.1 is that being power piping, they are further removed from UG-140 than B31.3. There maybe owner's approval required, I don't know. But you can also submit an inquiry to B31.1 via App H.

 

[BigInch]

CodeBum, Speaking for all of us here, welcome to the PPFM forum. Comments from committee members are especially welcome, official or unofficial, so we hope you will be a frequent visitor here, if not a full time resident.

Only put off until tomorrow what you are willing to die having left undone. - Pablo Picasso

 

[alex2010]

Thank you for your responses.