I think there are rods specifically for this- either 308 or 309, I forget which- one is used for stainless to stainless, other for stainless to carbon.
One issue is that you can have dissimilar metal corrosion, which would tend to corrode the carbon steel. While I know this CAN happen, I've never heard or seen anything that predicts how fast this happens, or if it's a problem in a specific application. And of course, you're contaminating your stainless steel, which reduces corrosion resistance of it.
Normally one would use 309 SS electrodes for a dissimilar (CS/SS) weld. To overcome a potential field welding problem would be to Shop weld a CS tab/tabs to the hood with 309 SS and then use the E70 electrodes to field weld it to the support.
You can get by with using E70 but there will be a time it will give you trouble.
Comeback with more information as to alloy used for the hood and the configuration of support connection.
To unclesyd, Stainless Steel series 430 and 18 guage thick, is being used for the two hoods. Also what do the initials CS stand for? and give me an idea how strong these tabs are (i.e.,how much weight can these tabs support). I had initially intended for the welder to apply continuous fillet welds between the A36 structural angle frame and the hoods but now you have brought up the idea of using these tabs and I am curious.
In my opinion 430 SS isn't the best material for this application. Normally if you weld 430 SS it will require an anneal procedure after welding. Also 430 SS isn't very corrosion resistant, it gets an oxide quite similar to rust.
No,the hoods have not yet been fabricated, however, I have nothing to do their fabrication. My responsibility is to design a vertical frame system from which will be hanging a horizontal frame welded to the top of the hoods. This entire framework is to support the entire weights of the hoods, inlet and outlet ducts, blowers, fire extinguishing system. There will be lateral forces and since the two hoods would bear such forces , I decided instead to have this horizontal frame bear the brunt of such forces.
