You both have very good points that I agree with. I didn't say structural welds are not important, they definitely are. I just don't see where such tight tolerances on groove angles make any difference in the quality of the weld or the performance of the structure. I would agree that sound engineering decisions need to be made in the selection of joint designs and parameters for the welding procedure. But again, I don't see where variables such as a change in the number of beads in a weld joint outside some tolerance band are that important. I doubt very many welders or inspectors are counting weld beads in the field to make sure the limits of this essential variable are not exceeded. This is a code that has been changed and revised so much that it does not flow well anymore and is very difficult to work with. I think they need to step back a bit and evaluate what factors are most important and how the requirements can be better organized and presented in a manner that the folks in the field can understand it and work with it better. It's kind of like the cartoon I see on jobsites that says "A zebra is a horse created by a committee."
Marty
Dear steveho
“As detail” column in figure 3.4 is for design and drawing. It means when you want to design or draw your joint you must follow its tolerances. D1.1-2000 page 81, double V groove weld butt joint, for example; your groove angle can be between 60 and 70 degree. Because groove angle is determined 60 degree and tolerance is +10,-0 degree.
Now, imagine the groove is designed 65 degree (it’s between 60 and 70 degree). During fit-up groove angle can be between 60 and 75 degree. Because fit-up tolerance is +10, -5 degree.
If you see all “AS fit-up” columns in figure 3.4, all fit-up tolerances are +10, -5 degree. so, it’s not obscure if you see it in figure 5.3 again. All tolerances in figure 5.3 are exactly same as figure 3.4 and they are repeated in chapter 5 for remembrance.
At last, you must follow figures 3.3 and 3.4 even for a non-prequalified joint. Because a change in theses tolerances is an essential variable (table 4.5, No.34).
Best Regards