Maximum Fillet Weld Size

[TJW]

I have searched previous threads and have not found an answer to this exact issue. For a detail similar to the attached sketch. Not sure if I attached it correctly so I'll try to also describe it:

Picture a 1 1/2" diameter pipe nested into the inside corner of an angle such that the top of the angle leg is even with the diameter of the pipe. The angle leg is 3/4" thick and the pipe is 1 1/2" dia (1.9" OD) x 0.2" thick.

AWS and AISC would tell me that the maximum size for a fillet along an edge is material thickness (for t <1/4") or material thickness minus 1/16" (for t > 1/4) and for two edges, I would use the thinner material thickness. In this case however the only "edge" thickness is the 3/4" angle because the weld to the pipe is not at an edge, it is welded to the O.D. So am I limited to fillet weld size by the 0.20" pipe wall or can I go larger since it is not an edge.

In case the sketch did not come through, to maybe avoid some additional question, with the edge of the angle even with the pipe diameter, I am considering the weld to be a fillet rather than a flare bevel.

Any thoughts would be appreciated.

 

[48v]

Assuming AWS D1.1:
I'm not sure you can rightfully call that a fillet, since the joint angle is greater than 100 deg. That said, the maximum fillet size limitation is meant to maintain an edge that can be used to measure the opposite weld leg. The provision only applies to welds in lap joints, so it doesn't technically limit you at all. All the same, you would be following the intention of the rule by limiting your weld to 11/16" based on the 3/4" angle leg.

 

[TJW]

Thanks for the feedback. I see what you are saying about the angle of the "fillet", but not sure what to call it. However, the intent of my question was about the size limitation which you graciously answered for me.

Thank you.
TJW

 

[gtaw]

The size limitation you are quoting is applicable to lap joints. The sketch does not depict a lap joint, so the size limitation does not apply.

If the angle between the two members is between 80 and 100 degrees, it is a fillet weld. If the angle is less than 80 or more than 100 degrees, it can be approached as a skewed T-joint.

Assuming this is a structural application, the weld size can be sized to equal the strength of the members being joined. One limitation is that the base metal cannot be stressed to more than 0.4 times the yield strength of the base metal in shear and .6 times the yield strength of the base metal when loaded in tension.

Best regards - Al

 

[TJW]

Thank you for that additional clarification.

 

[Duwe6]

nice sketch; and I agree with GTAW.