Head Fabrication

[PAN]

In my company standard, head shall be fabricated from 1 piece. However, the segmental plates may be inevitable for large diameter of vessel.

Please advise me about the additional inspection program for QA/QC during head fabrication.

 

[bmoorthy]

If the dish head is formed from the welded plate then you may have to check the following as a minimum


1) NDE (radiography of the weld Seam)
2) WPS/PQR
3) If the client has called for hardness, then check hardness

 

[PAN]

bmoorthy,

Thanks for your comment. For further understanding, please advise me in the following queries :-
- Should we confirm RT after forming?
- Should we confirm MT/PT after forming?
- What is the acceptable hardness?

In my case, head material is 2.25Cr-1Mo steel. Vessel diameter is 2 to 3 m (hemispherical head).

 

[pve5]

Pan ( mechanical )
I suggest as follows :
1) RT before forming
2) RT after forming
3) MPI after stress relieving
4) Acceptable heardness for 2.25 Cr-1Mo 225 BHN