Attaching a nozzle to shell using only fillet welds from the outside

[jgibbs22]

Hey Everybody:

Has anyone ever attached a nozzle to a cylindrical shell while only performing an external fillet weld? I want to do this for an alteration, and while I think I can, just wanted to see if anyone has done this before. Can you do it without any weld inspection if you are under DPS6 using FIg. UW-16.1(u)?

 

[GenB]

Is it ASME__ what Section__ want size__ what type___

 

[GenB]

Is it ASME__ what Section__ want size__ what type___

 

[jgibbs22]

ASME section VIII div 1, 4" schedule 5 nozzle with 4"slip on flange

 

[Duwe6]

Nope - fillet only fails to meet Code. If you get the nozz wall thickness similar to the shell thickness, that weld can be made full-penn from the OD, set-in. Just takes a GOOD open-root pipe welder. Or if you are insistent on using Sch5, same welder can gap the nozz fit-up slightly and set it on. Both Set-In and Set-On meet Sect VIII Code. Just have to be full-penetration.

 

[MJCronin]

Duwe6 gives good advice...... I agree that a full penetration weld is the correct choice here

A fillet welded nozzle is always a simpler and cheaper way to make a nozzle on a pressure vessel.

Unfortunately, ASME and EN pressure vessel codes do not permit this type of weld in this nozzle size.

Also, the schedule 5S nozzle seems like a very bad choice here. 5S piping is nearly impossible to properly weld.....IMHO

A schedule 40S nozzle with a slip-on flange would be the best choice here.

MJCronin
Sr. Process Engineer

 

[SnTMan]

What is DPS6?

Regards,

Mike

 

[Shmulik]

NPS 4" Sch. 5 nozzle fails to meet UG-45 min. wall thickness, unless your nozzle is access or inspection opening.