Centerline misalignment shell/head Fig UW.13.1

[ElCidCampeador]

Hi,

Pressure vessel designed acc. to ASME VIII Div.1, material SA 516 Gr.60.
This vessel has a shell and an ellipsoidal head 2:1 that have to be welded with a butt weld according to fig. UW 13.1
In particular:
+Shell: I.D. 1220mm
O.D. 1390mm
Thk. 85mm
+Head: I.D. 1200mm
O.D. 1380mm
Starting thk.90mm
M.A.F. thk: 80mm
I'm verifying if condition of figure UW-13.1 is ok:

(difference between shell/head centerline)<=1/2(th-ts)
In this case: 7,5<=0,5*(90-85) -> 7,5<=2,5 FALSE

Now I have to weld shell with head, what should I have to do to make it acc. to code? Is necessary an internal/external transition?

Thank you

 

[SnTMan]

OK, so is it possible to reduce the cylinder thickness to 85mm, even for a short course? Match OD or ID, again for a short course? Introduce a short conical section?

The problem with sloppy work is that the supply FAR EXCEEDS the demand

 

[david339933]

Fair enough.

 

[r6155]

ElCidCampeador
Your original post say +Shell: I.D. 1220mm +Head: I.D. 1200mm
After this you say "...I have to respect I.D. of shell because of internal cartridge dimensions (fixed by client)".
What is true?.

Regards
r6155

 

[ElCidCampeador]

ElCidCampeador
Your original post say +Shell: I.D. 1220mm +Head: I.D. 1200mm
After this you say "...I have to respect I.D. of shell because of internal cartridge dimensions (fixed by client)".
What is true?.

Regards
r6155

Both, because 1220mm is fixed by client's internal, 1200mm is fixed by forming limits of head supplier (it can't respect 1220 but only 1200). Consider that internal cartridge parts are present only in the shell.