In my experience, yes, you can overlay an AISI 410 steel lining with 316 or 317 stainless steel. From a technical point of view, OK.
Now, the doubt I have is whether it is convenient from an economical point of view. From what you say, seems that you're talking about an existing chemical reactor which is already installed and has been used for a while. In this case, you'll have a lot of trouble before the 316 stainless overlay is complete and ready for operation.
I suggest that you make a cost comparison between applying the new overlay on the existing vessel and making a new one out of 516 Gr 70 carbon steel cladded with 316 stainless.
Attention though! In the estimate you must take into account ALL costs involved, and not just the materials cost.
Giovanni S. Crisi
Sao Paulo - Brazil
In the weld metal itself, you will probably be ok up to about 30% dilution (no martensite formation), your weld metal would typically be austenitic with 5-10% ferrite based on typical chemistry of 316/317/410 weld metals. However, the HAZ of the overlay that would be in the 410 might be a problem. 410 usually requires PWHT to temper the martensite that would form in the HAZ of the new overlay. Otherwise, there could be a good possibility that cracks will develop. However, if you give the vessel a Stress relief PWHT, you will have to develop an overlay procedure for the 316/317 that doesn't pick up much carbon from the 410 or you will get sensitization during the PWHT. You would obviously have to start with 316L or 317L to begin with. Alternatively, you could do one layer of 316/317, then PWHT, and then deposit another layer of 316/317 that would not need PWHT. (Technically wouln't need PWHT, but check any codes to make sure.) By the way, what did NiDi say? They certainly know what they are talking about.
I haven't heard back from Nidi yet, but when I do, I'll post their suggestions as well.
Thanks for the responses, it definitely looks like this won't be an easy one to tackle.
Darren.
Typically, we use a layer of 309L on carbon steel before going on with a second pass of stainless. eg 308L, or 316L. Maybe it would be better to have a layer of 309L onto the 410, then PWHT, then 316L/317L?
Comments?
Since 410 already has significant alloy in it, using 309L would be accepable, but not necessary. The less costly 316L/317L should give you enough alloy to avoid martensite &/or cracking in the weld if you keep the dilution to reasonable levels. However, if you are planning on using SAW, then 309L might be a consideration due to high dilution. What process are you planning on using?
We would be using an automatic flux cored welding procedure. So a layer of 309L and the the final layer of 316L/317L shouldn't be out of the question then. We can control the dilution of the 309L pretty well to keep it as low as possible.
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