Stainless Steel Minimum Fillet Weld Size

[KB4444]

Carbon steel welding is governed by CSA W59; which provides Table 4.4 for the minimum fillet weld sizes for welding different material thicknesses. I can not find anything outlining the same requirements for stainless steel.

I have (2) pieces of 304 stainless steel to be fillet welded together; a 1/2" piece is being welded to a 3/4" piece. The load being carried through the weld is low, only requiring a 1/8" weld with the weld length available. Is there a similar table/code requirement for stainless steel that provides the minimum size required for the different material thicknesses? The situation I have is very repetitive so the smallest weld size to meet code is required, not just picking 1/2 the material size to follow a common practice (but maybe this is code).

 

[EngDM]

Read clause 1.7, for stainless steel welding W59 defers to the American AWS D1.1

AWS D1.1 then says that AWS D1.6 should be used for stainless steel structure welding. I haven't been able to find anything specifying minimum fillet welds.

As far as I am aware, the minimum fillet weld is to prevent cracking in the weld itself due to temperature fluctuations, so I'm not sure if the base material being stainless steel vs carbon steel; unless of course they have wildly different thermal properties.

P.S. make sure you specify an applicable welding process as well, since some of the carbon steel ones may not be applicable to stainless.

 

[lexpatrie]

Stainless transmits thermal more poorly than normal steel. Factor of 10 I think.

 

[Smoulder]

AISC spec 370-21 table J2.4 gives 5mm = 3/16" based on the 1/2" plate (the thinner piece). Same as for normal steel.