T Joint Weld Size Determination

[Veer007]

Hey Guys,

As discussed in earlier threads, T joint has no maximum weld size, then what was my concern is, Is there any criteria for bare metal thickness should be min depending size of weld.

I have to weld 6mm fillet weld on 3mm thinner plate. Is this possible?

Thanks in advance!!

 

[Lomarandil]

It is possible.

In some cases, the capacity of the connection will be limited by a tear out failure of the thinner base metal.

In extreme cases, it may be infeasible to build up a large weld without burning through a particularly thin base metal (think composite decking).

----
just call me Lo.

 

[Veer007]

yeah right, But I don't think, in composite decking steel deck can be part of composite as shear stud penetrate through deck and connected with steel beam by weld and bond with concrete above.

But steel deck? just welded with steel beams, right. doesn't seem part of composite, Am I wrong?

Thanks in advance!!

 

[r13]

Veer007,

This is a very short blog worth to read. Link. After that, you can do more research on your own.

 

[Veer007]

.

Thanks in advance!!

 

[dauwerda]

Why does it need to be a 6mm weld? Obviously that will result in a weld much stronger than the base metal.
I am not aware of any codified restrictions, however this will most likely result in serious warping and deformation of the thin plate due to the heat input of the weld.

So to restate, I am not aware of a codified restriction, but this would not be a good design practice.
Why not reduce the size of the weld to all that is needed to develop the strength of the base metal?

 

[kingnero]

A 6 mm fillet weld will almost inevitably be three runs each side. That bottom plate will try to go all directions.
How much deformation do you accept?

 

[r13]

Can you wait it cool before another pass, and work evenly from both sides? Just curious.

 

[Veer007]

you are right, all we have to do is develop weld capacity only depending the thinner part joined, right?

greater weld increase deformation? no, we don't allow any deformation.

that's fine, we can do. But I am not aware how much base metal will be affected?

Thanks in advance!!

 

[r13]

Veer007,

Going forward, I think you need to consult with a welding engineer, to select a process and develop a welding procedure.

 

[kingnero]

no, we don't allow any deformation.

Well that doesn't leave you with much options. 3 mm plate is going to warp as soon as it sees a welding torch coming nearby.

There is also absolutely no need for 2 6mm welds on a 3 mm base plate. But you've got two issues here: the weld size and the deformation issue. If no deformation is acceptable, consider a bolted joint.

 

[Veer007]

yeah guys, much better

Thanks in advance!!

 

[klaus.]

you can (try to) do it...but...makes no sense ...