Welding 5mm stainless pipe to plate.

[Sk_rmouche]

Hi there,

I am making a stainless vessel for a compressed air drier out of a piece of 5mm 8" SS pipe and I have finished the copper coil for the refrigeration unit. I now have to weld that plate onto the 8" pipe.

For the bottom I had a piece of 10 mm 316L plate that was just slighty bigger to fit as an end cap. I tig welded this plate with a root pass and then a filler pass with 316L filler metal. The problem is that I have spent too much time on this joint and the plate has massive distorsion ( mushroom style with the edge pointing up ).

This is not a problem for this particular project, but I would like to do things right for the top plate. It is 6mm thick ( the pipe is 5 mm thick ).

Should I bevel the pipe or is it not necessary for 5 mm ?



Thanks,


Vincent.

 

[Brad93]

No need to bevel that

 

[Sk_rmouche]

Thx Brad, I won't mess with the edges then.

 

[Brad93]

Thx Brad, I won't mess with the edges then.

No. That thickness you should be getting a good bit of penetration. It's only holding airline pressure, what 10bar max?

 

[Sk_rmouche]

Yes design pressure is 10 bar. I probably could have used thinner stuff but I go my hands on this schedule SS pipe for a pack of beers so ... 5 mm on the top plate also gives me option if I want to tap of weld fittings.

 

[Migmad]

Dont bevel as that is likely to increase your distortion, can you clamp the base plate to something thick to hold it in position?

 

[Sk_rmouche]

Yes, I have a small plate of 10mm 6061. I will get all the drilling and other stuff done before closing the vessel as I won't have any access afterward. I will post the result here.

So this is probably what gave me the distorsion on the other side ( 10 mm 316 plate ), I did put a bevel, thinking that it was needed for the root joint ...

 

[Sk_rmouche]

Thought I would share the final result :

Hardly any distorsion compared to the other really thick plate that looks like a giant SS mushroom ! Not an issue here but still looks funny.