410 stainless with SAW

[twoheads]

can any body forsee any mechanical problems, I have a 8"NB , 30mm thick tubular test coupon to qualify. the electrodes in the past have been horrendous to work with so im im now thinking of, root , hot pass and splitter with GTAW, fill and cap with SAW, all the parts to be welded are easily accessible with this process.

Thanks in Advance.

 

[weldtek]

You specified 410 not 410S, so, unless you have a lot of experience welding this material, I would anticipate problems. Other than the obvious preheat, interpass and DHT, and PWHT considerations, I'd be very cautious with selection of consumables. Carbon, Silicon and Manganese can make or break it for you.

 

[pradipgoswami]

Hi,

410S is a martensitic stainless steel,which could be welded by matching consumables,typicaly ER410NiMo type.This electrode has slight modifed chemistry.Weld metal deposited by these electrodes is modified to contain less chromium and more nickel than weld metal deposited by E410 electrodes. The objective is to eliminate ferrite in the microstructure, as ferrite has a deleterious effect on mechanical properties of this alloy. Final postweld heat treatment typically should be in the range of 1150°F [620°C].

Altenatively austenitc fillers (ER 309L type) with suitable S.S Fluxes could be used.All manufacturers, e.g ESAB, Lincoln Electric and others have good austenitic filler wire & flux combination.

Another option could be Inconel-82 fillers, the choice could be special metals(

http://www.specialmetals.com).

ASME Sec VIII, DIV allows exemption from PWHT, for welding of this alloy,with austenitic electrodes provided:-
-carbon content in the weld does not exceed 0.08%
-for thicknesses over 3?8 in. (10 mm) to 11?2 in. (38 mm) if a preheat of 450°F (232°C) is maintained during welding
and that the joints are completely radiographed.

If the consumable selction is from reputed manufacturers with proven performance knowledge,fillers with matching chemistry with PWHT is a good option. With austenitic consumables, without PWHT the HAZ always remain a suspect due to high hardness and low ductility.

The attached file would provide required information on matching electrodes.

Thanks

Pradip Goswami.

 

[twoheads]

Yeah it is 410s,
Fantastic information Pradip , thank you very much.

 

[pradipgoswami]

Hi twoheads,

Appreciate your feedback,feel free to drop a line if you require any more info.

Thanks.
Pradip

 

[GRoberts]

A word of caution if you end up using the 410NiMo, the final PWHT temperature should not be "in the range of 1150F", but should be 1150F maximum. This is because the lower critical transformation temperature is not much above 1150F.