Clad Plate use in Pressure Vessel need a Fabricator's view - Eng-Tips

We are designing vessels (various 12 - 15 ft diameter) which each use a single shell belt of clad plate (mill bonded) which coincides with an internal wet process condition.
Cladding is 0.1 inch x AISI-317L over 7/8" 516-70
The plate, and hence the shell belt will be 8 ft wide.
The internal process section needed to be lined is only 7'-6" wide and there are (2) flat heads (just baffles with no real pressure requirement) dividing the vessel laterally.
These baffles are made from Duplex steel.

If we specify the cladding to be removed over 3.5" of the plate edge to permit the attachment of the to the base shell (and then overlay the inside weld for about 1/2") are we creating unnecessarily difficult work?

The other option would be to put the shell circ seam just inside the baffles but then we would probably need to crop the clad plate down to 7'-2" wide and weld overlay roughly 2" each side to keep the seam away from the internal plate edge.

Thanks for any advice

David Flareman

Without knowing the details of you modification if I were you I would weld AISI 317L support rings for the baffles on vessel shell. The duplex plates would be fixed on the support rings through bolts and washers on oblong holes of support ring to absorb duplex plates expansion.

I feel that it is not your case, but if you need your baffles to be completely leak free the above suggestion doesn’t work.

Good luck

luismarques
SnTMAN
I had originally thought that I might weld the baffles to the cladding but I'm uncertain about the strength of the shear bond between the clad and the base plate and the impact of a heavy weld (3/8" fillet?) from the baffle onto the very thin (0.1") cladding. Although the baffle is lightly loaded, it does carry a shear load, due to modest pressure differential, out from the vessel center toward the end, of roughly 150 lbf/in of circumference.
Do you have knowledge or experience that would allow me to believe this to be acceptable?

And yes , because of this pressure load I do need to seal the baffle edges.

Thanks for jumping in
David