Wet Flue Gas Desuplurization ( WFGD ) - Shell repair
Wet Flue Gas Desuplurization ( WFGD ) - Shell repair
(OP)
I did not know where to post this as I do not know what original code of construction these are built to. I am assuming ASME Sec. 8 Div. 1.
We want to repair erosion on the floor ( 2205 Duplex S.S) using 1/4" plate of the same material - welding with NiCrMo-3 as per the customer. My question is , if we do a full sheet 4' x 8' , does it need reinforcing plug welds. I have searched through Sec. 8 and cannot find anything pertaining to patches.
Thank you in advance and I am sorry if this thread is in the wrong category.
We want to repair erosion on the floor ( 2205 Duplex S.S) using 1/4" plate of the same material - welding with NiCrMo-3 as per the customer. My question is , if we do a full sheet 4' x 8' , does it need reinforcing plug welds. I have searched through Sec. 8 and cannot find anything pertaining to patches.
Thank you in advance and I am sorry if this thread is in the wrong category.





RE: Wet Flue Gas Desuplurization ( WFGD ) - Shell repair
RE: Wet Flue Gas Desuplurization ( WFGD ) - Shell repair
Welding procedures are generally required to be qualified per ASME IX. Whereas the repairs are most likely considered weld build up to restore thickness the procedure should be qualified as a groove weld with tensile tests and bends.
There are problems with this type of repair. While the NiCrMo-3 will resist the corrosion, the HAZ of the 2205 may well not due to the galvanic mismatch and un-removed heat tint on the 2205 duplex. There has also been some concern that corrosion is MIC related and the weld repair zone may be ideal for microbial colonization. What one ends up with is a continuous weld repair cycle. And trust me, this indeed is what is happening to a number of wet scrubbers fabricated from 2205 that I am highly familiar with. Blend grinding the deposited weld metal coupled with glass bead blasting or pickling (pickle paste) to remove the heat tint is advised.
RE: Wet Flue Gas Desuplurization ( WFGD ) - Shell repair
RE: Wet Flue Gas Desuplurization ( WFGD ) - Shell repair
RE: Wet Flue Gas Desuplurization ( WFGD ) - Shell repair
We were planning on seal welding it to the floor with approx. a 3/16" seal weld. But with the flex in the floor and the plate itself, I didn't know if there was somewhere that said you had to put a plug weld every X amount of feet. I didn't even know what the original code of construction let alone repair.
RE: Wet Flue Gas Desuplurization ( WFGD ) - Shell repair
RE: Wet Flue Gas Desuplurization ( WFGD ) - Shell repair
RE: Wet Flue Gas Desuplurization ( WFGD ) - Shell repair