Complete joint penetration (CJP) 3

[calmox]

Hi Experts.

To those with great knowledge and experienced. I just want to clarify a Build Up Beam Fabrication with join design of Butt Tee joint but full penetration.
My Question is Is there still a required leg size of weld although the process is CJP. Please quote with reference if there is an existing code for this issue
Thank you so much... Cheers.

 

[MotorCity]

You do not specify a weld size for a CJP weld. By definition, the weld size is equal to the thickness of the part being welded.

 

[dhengr]

Calmox:
If someone actually designed that weld joint btwn. the web and the flange of a built-up beam, they would likely discover that a CJP weld was not really required. The CJP weld joint is seldom actually needed, it just seems to be a fall-back detail for those who don’t know any better. After all, that’s what hot rolled beams look like, but that’s due to the nature of their manufacture, not a real stress need. The CJP weld involves the cutting of bevels on the web plate. These bevels must be wide enough (open enough) to allow good welding at the root passes, depending upon your welding process and equipment, and this determines the weld size, amount of filler metal needed, number of passed needed, etc. This is all part of the joint design. Then, there is likely a small reinforcement fillet in the 90̊ corners btwn. the web and the flange, because you really can’t make the weld otherwise. And, there is also the question, should you back gouge the root/land, to sound weld metal, before welding the root on the second side. The CJP weld joint is usually more expensive than the required fillet welds on both sides of the web to the flange.

The American Welding Society (AWS), Lincoln Electric, and others have good literature on these subjects. Get some of this material for your own edification.

 

[dik]

also a good location for a tri-axial stress state and possible brittle fracture...

Dik

 

[calmox]

thank you so much guys such a great help for your great knowledge.. cheers..