Welding Tips and Tricks

Ha all
I'm fixing some cracks in a stainless tub for uses on a medical machine. I know that it is stainless can I use ER308L or do I need different rod. Please help
Thanks

It depends what kind of stainless you are working with. You need to know that. If its 304 you can use 308 if its 316 you need to use 316l. And make sure to purge it and no undercut. All the medical stuff I have done has been with 316.

I expect someone will disagree - but in my limited experience most commercial medical equipement & food grade stainless is 316 - so you should stick with 316 filler rod - it's never great welding something of unknown material - but I believe 316 filler can be used on most non critical parts of lower alloy numbers without a problem - using 304 or 308 on higher number alloys seems to be prone to cracks in the heat affected zone & weird corrosion issues - not something you want.

I tried 308l on a junk one part. The part also has a heat blanket glued to the back side that can not be removed. I tried welding it but when the puddle hot 1 second in I think it melted the blanket and the puddle blow out from the middle. I don't think 308l would that. I don't know where to go from here other then the 316l. Any suggestions.
Thanks

You're going to have to lose the backing somehow.

It will continue to contaminate your weld as long as it's within the HAZ, even with 316l filler.

One option,

Weld it out with 308, 9, or 16, and let it go to hell, so the heat burns the backing away. Grind it clean, then do a shallow 309 root. Then cap with 316.

I agree with Otto you need to loose the backing. Could you use a solvent to eat the glue away so you can remove the heat blanket and then re adhere it to the tub after you are done making the repair? I would go with the 316 l for safety. You don't want to use 308 on 316 cause your weld will now have the same corrosion resistant properties as the base metal.

First of all im newbie so sorry for the stupid questions

Quote from http://www.arc-zone.com/index.php?main_ ... ts_id=8698

ER308L AWS A5.9 CLASS ER 308L
ER308L is similar to 308 but contains an average .02% carbon producing a
weld deposit with good resistance against intergranular corrosion caused by
carbide precipitation. 308L is commonly used for welding AISI types 304L,
308L, 321 and 347.

So this is for 304 type austenitic stainless, but what it does differently? Creates more ferritic phase on the weld than 316L rod?

There are no stupid questions here.

That, however, has not stopped me from giving a stupid answer or two...

There are a couple of folk here who know the metallurgy well enough to answer your question. They're not daily visitors, though, so it may take a while to get an answer. Jody might know, so I'd also pose that question directly, under the "contact us" tab on www.weldingtipsandtricks.com as well, though it might take a while to get a response there, as he gets many questions.

Welcome to the forum!

Steve S

Thanks mate!

I think its just better to wait... Jody puts so much effort on videos that sometimes I even wonder how he manage to create decent and usefull videos every week, so that in mind don't want to hesitate him