Fabricated 4way cross section
Fabricated 4way cross section
(OP)
Dear Engineers,
We are using a fabricated Cross 6” x 6”,Sch 80 on the inlet and outlet side of the manifold,Working pressure is 1440 psi.Can you please tell me how to check(calculation) if this design is passing? MOC A234 WPB. Pic is attached for your ref
We are using a fabricated Cross 6” x 6”,Sch 80 on the inlet and outlet side of the manifold,Working pressure is 1440 psi.Can you please tell me how to check(calculation) if this design is passing? MOC A234 WPB. Pic is attached for your ref





RE: Fabricated 4way cross section
RE: Fabricated 4way cross section
RE: Fabricated 4way cross section
RE: Fabricated 4way cross section
RE: Fabricated 4way cross section
RE: Fabricated 4way cross section
for special design, better to perform finite element analysis (FEA) to ensure stress integrity of the equipment/Component.
And to ensure the integrity of product that you have fabricated just follow normal inspection/testing, UT and hydrotest for welding strength.
RE: Fabricated 4way cross section
RE: Fabricated 4way cross section
My motto: Learn something new every day
Also: There's usually a good reason why everyone does it that way
RE: Fabricated 4way cross section
RE: Fabricated 4way cross section
What you're doing is a bit odd, but I can't see why this should be any different than welding two branches side by side, though there are rules somewhere in that section about minimum distance between them.
A forged component would solve all your problems....
At a design pressure of 1440 psig you can't afford to make mistakes.
You also need to talk to whoever is approving / authorising / inspecting this thing to make sure they are happy.
At the very least it's some sort of start point for your analysis.
My motto: Learn something new every day
Also: There's usually a good reason why everyone does it that way
RE: Fabricated 4way cross section
RE: Fabricated 4way cross section
You can't write a code covering everything so need to apply some judgement from time to time.
The reinforcement pad is almost definitely needed on both branches, but that you can work out quite easily.
My motto: Learn something new every day
Also: There's usually a good reason why everyone does it that way
RE: Fabricated 4way cross section
RE: Fabricated 4way cross section
I'm happy to be pulled up on this, but I think it needs some explanation as to why it is not a valid approach?
My motto: Learn something new every day
Also: There's usually a good reason why everyone does it that way
RE: Fabricated 4way cross section
Interference in the HAZ?
Warping during fabrication?
Axial stress?
Bending Stress?
Torsion?
Stress concentration factors?
There's just very little metal left that can handle any kind of a load.
I'd tend to leave it only for someplace I would know will always be in a very low stress condition.
RE: Fabricated 4way cross section
http://www.notokfittings.com/equal%20tee%20buttwel....
Unreinforced (stub-in) type intersections in this pressure and diameter range will fail ASME B31.1.
If pad reinforced intersections are used, it may become to expensive/difficult to fabricate.
Have weld-o-lets been considered ? They have slightly more cost but the pressure reinforcement is assured and fabrication is easy.
http://www.bonneyforge.com/resources/BC.pdf
I also have a lot of trouble with this " I just welded something up, now you engineers tell me why I can't use it" approach.
If your piping fabricator does not understand simple piping/pressure vessel concepts like pressure reinforcement, there is real trouble here.....
MJCronin
Sr. Process Engineer
RE: Fabricated 4way cross section
Let alone the fact IF you can get a full WOL (i.e. 6" to 6").
RE: Fabricated 4way cross section
RE: Fabricated 4way cross section
Piping Design Central
RE: Fabricated 4way cross section
RE: Fabricated 4way cross section
RE: Fabricated 4way cross section
RE: Fabricated 4way cross section
RE: Fabricated 4way cross section
RE: Fabricated 4way cross section
RE: Fabricated 4way cross section
(a) Except for branch connections and assemblies of standard pipe and fittings joined by circumferential welds, the design pressure of each component fabricated by welding, whose strength cannot be determined, must be established in accordance with paragraph UG-101 of the ASME Boiler and Pressure Vessel Code (BPVC) (Section VIII, Division 1) (incorporated by reference, see§ 192.7).
(b) Each prefabricated unit that uses plate and longitudinal seams must be designed, constructed, and tested in accordance with section 1 of the ASME BPVC (Section VIII, Division 1 or Section VIII, Division 2) (incorporated by reference, see§ 192.7), except for the following:
* * * * *
(d) Except for flat closures designed in accordance with the ASME BPVC (Section VIII, Division 1 or 2), flat closures and fish tails may not be used on pipe that either operates at 100 p.s.i. (689 kPa) gage or more, or is more than 3 inches in (76 millimeters) nominal diameter.
RE: Fabricated 4way cross section
The thing pictured needs some reinforcement but is simply a branch connection x 2.
Remember - More details = better answers
Also: If you get a response it's polite to respond to it.
RE: Fabricated 4way cross section