Good Afternoon:
Segmented Vessel Heads, Standard Procedure. Who among you can tell me what the Industry Standard Practice is used in the shop fabrication of large diameter (>30’Ø & >1”Thick) ASME Semi Elliptical heads? What is taught in the trade schools and apprenticeship programs? When ordering, what allowance if any is made for weld shrinkage? Should a root opening be specified in the purchase order or would a zero root opening be specified? I assume that a head manufacturer would fabricate the segments and crown plate without any allowance for root opening, pre-assemble and tack weld the head, QC check, match mark and disassemble for shipping. Is this correct? What textbooks or publications are available that would spell out the Industry Standard Practice for fabricating ASME segmented heads?
Thank you, Kent.