Branch connection spacing 1

[kryanl]

Hello. I was wonderin gif anyone could tell me where in ASME B31.1 does it reference the required spacing between two or more branch connections on a pipe header. I am talking mainly about weldolets. How close can two weldolets of the same size be on the same header? Can they overlap (maining, can they be located 180 or even 90 degrees apart?) I know there is a rule concerning the spacing between welds (can't remember what that is), and would think that might be the same governing rule.

I know I'd come across it before in the code, but be darned if I can find it again. Would be very appreciative if someone can tell me the section to find it, or even give me the rule of thumb.

Thanks!

Kay

 

[JohnBreen]

Hi Kay,

You will want to read B31.1 paragraph 104.3.1,G.7 and G.8 (these are the last couple of paragraphs before 104.3.3 Miters). Basically the best thing to do is space the openings no closer than they can be without overlapping the reinforcing zones of each opening (reinforcing zones (r1) as defined in paragraph 104.3.1,G). However, if you must make the spacing closer that that it shall be per the requirements of the paragraphs cited above. It must be remembered that you cannot "take credit" twice for area of reinforcement at the two openings. If you can find a copy of Pipe Fabrication Institute Bulletin PFI-ES-7 (Minimum Length and Spacing for Welded Nozzles), you will find guidance there but this document is no longer referenced by the ASME B31 Codes for Pressure Piping.

Even with integrally reinforced (weld-on or weld-in) fittings you should try not to overlap the defined reinforcing areas.

Regards, John.

 

[MJCronin]

Kay

http://www.pfi-institute.org/Product.htm....

Good luck...