Nameplate Stamping

[yl0525]

I have a drum with bottom smls elips head joint to a smls pipe and finally welded with a std flange with blind cover. Noted that there is no longitudinal seams involved but top and bottom circ seam are spot RT.

Anyone could advise whether the nameplate shall be stamped RT-2 or RT-3?

Thank you.
YL0525

 

[vesselfab]

are the spot x-rayed in accordance with u-11(a)(5)(b) or uw-11 (b)?

and what joint efficiency are you using for head and shell?

 

[yl0525]

Joint efficiency used are 1.0 for both smls shell and smls head, spot x-rayed to uw-11(b).
What if it is spot x-rayed to uw-11(a)(5)(b)?

 

[doct9960]

yl0525,

Joint efficiency used are 1.0 for both smls shell and smls head, spot x-rayed to uw-11(b).

Joint efficiency should be per Table UW-12 for Type 1 or 2 butt joints radiographed in accordance to UW-11(b). So E = 0.85 for Type and E = 0.8 for Type 2. Nameplate to be stamped RT-3.

What if it is spot x-rayed to uw-11(a)(5)(b)?

Joint efficiencies would be E = 1. Nameplate to be stamped RT-2.

 

[brandonb73]

Someone correct me if I'm wrong, these must be 2 different shots, the spot RT for UW-11(b) connot be used to also satisfy UW-11(a)(5)(b).

 

[yl0525]

Thank you brandonb73 and doct9960 =)

 

[vesselfab]

The code says if you want to use E=1.0 you have to radiographed seamless sections joined together per UW-11(a)(5)(b)

if your calculations say E=1.0 you have to stamp RT-2

if you calculations say E=0.85 then you have to stamp RT-3

It's really RT-2 but if you need to keep MAWP down some then you could use RT-3 and 0.85% on calcs.
Some may argue with this...but....

 

[GenB]

RT-3 for spot rt performed