Angle weld to plate 3

[JStructsteel]

Welding a 7/8" thick angle to a 1/2" embed plate, what would you use for the min. weld. I am finding 1/4" min.
Thanks

 

[dik]

Maybe a little thicker.

Maybe a different code...

-----*****-----
So strange to see the singularity approaching while the entire planet is rapidly turning into a hellscape. -John Coates

-Dik

 

[RenHen]

Is that mathcad sheet based on the "Minimum Size of Fillet Welds" table from the AISC manual? (Asking because it looks like it but I thought that table used the thickness of the thinner part being joined to determine the minimum weld size)

 

[271828]

From the AISC Specification Table J2.3, the 1/2 in. plate controls and the minimum fillet weld size is 3/16 in.

 

[dik]

Based on the 7/8" thick plate... not the 1/2".

-----*****-----
So strange to see the singularity approaching while the entire planet is rapidly turning into a hellscape. -John Coates

-Dik

 

[WinelandV]

IIRC, the Canadian code has a minimum thickness check based on the thicker part.

Edit: Ninja'd by 1 minute. Yeesh.

Please note that is a "v" (as in Violin) not a "y".

 

[WesternJeb]

I am with DIK. The minimum size of fillet welds is when you are welding along the edge of a steel plate. The thickness of a plate, when you are welding to the face of it, has nothing to do with minimum weld size. See Fig. C-J2.1 in AISC 360 commentary.

 

[dik]

It's to prevent too rapid cooling, and possible cracking. It is possible that a smaller fillet may be used with pre-heating if there is a procedure for it...

-----*****-----
So strange to see the singularity approaching while the entire planet is rapidly turning into a hellscape. -John Coates

-Dik

 

[dik]

Is the American code different?

-----*****-----
So strange to see the singularity approaching while the entire planet is rapidly turning into a hellscape. -John Coates

-Dik

 

[dik]

Program revised a bit...

-----*****-----
So strange to see the singularity approaching while the entire planet is rapidly turning into a hellscape. -John Coates

-Dik

 

[RenHen]

The AISC steel construction manual has a minimum thickness check based on the thinner part. The commentary section adds "2b. Limitations Table J2.4 provides the minimum size of a fillet weld for a given thickness of the thinner part joined. The requirements are not based on strength considerations, but on the quench effect of thick material on small welds. Very rapid cooling of weld metal may result in a loss of ductility. Furthermore, the restraint to weld metal shrinkage provided by thick material may result in weld cracking. The use of the thinner part to determine the minimum size weld is based on the prevalence of the use of filler metal considered to be "low hydrogen." Because a 5/16-in. (8 mm) fillet weld is the largest that can be deposited in a single pass by the SMAW process and still be considered prequalified under AWS D1.1, 5/16 in. (8 mm) applies to all material 3/4 in. (19 mm) and greater in thickness, but minimum preheat and interpass temperatures are required by AWS D1.1. Both the engineer of record and the shop welder must be governed by the requirements."

 

[phamENG]

dik - AISC only calls for a check based on the thinner part joined. There are special material requirements for rolled and built-up 'heavy shapes' (flanges or plate sections thicker than 2") to minimize fabrication damage during welding. Everything else is generally handled with the welding procedure with preheats, etc.

 

[dik]

Thanks... didn't know that... I think I'll keep my approach... if 1/2" then 3/16 fillet weld is OK then...

-----*****-----
So strange to see the singularity approaching while the entire planet is rapidly turning into a hellscape. -John Coates

-Dik

 

[JStructsteel]

I went with 5/16" weld, but I didnt upsize my plate thickness. I could do a 3/16" weld with 1/2" plate if my strength is there?

 

[kingnero]

I'm missing a major part of the information here - how's the angle loaded? What are the actual loads?
No point in determining weld size from the base material thicknesses, unless the thinnest part is loaded to it's max.

 

[OldDawgNewTricks]

The AISC minimum weld size used to be based on the THICKER part joined. In 2005, it was changed to the THINNER part joined. The commentary said the change was due to the prevalence of low-hydrogen filler metal.

 

[dauwerda]

I am with DIK. The minimum size of fillet welds is when you are welding along the edge of a steel plate. The thickness of a plate, when you are welding to the face of it, has nothing to do with minimum weld size. See Fig. C-J2.1 in AISC 360 commentary.

WesternJeb, you are describing the maximum fillet weld restraints, not the minimum

As others have mentioned, the minimum weld size here is not based on strength requirements, but to ensure the weld doesn't cool too quickly causing embrittlement issues. It should go without saying, that the weld itself needs to be the larger of the size required for strength and the minimum weld size allowed based on thickness.

Is the American code different?

AWS D1.1 has both requirements - depending on the weld process (see footnotes). If a nonlow-hydrogen process is used it is based on the thicker part, if pre-heat or a low-hydrogen process is used it is based on the thinner part:

As others have noted, if you are following AISC, and not just D1.1, AISC assumes it is a low-hydrogen process and goes straight to the thinner part.

 

[WesternJeb]

Dauwerda, thanks for calling me out. 100% Correct.