Determining weave bead width

Q: When welding with 1/8-in. E7018 welding rods, what's the maximum width for weaving? I've heard different answers but can't find anything in the D1.1 structural code.

A: For the process you mentioned, shielded metal arc welding (SMAW) with E7018, you will not find many restrictions on weave/oscillation width in AWS D1.1, but there are some. Table 4.6 in Clause 4—"Qualification" limits weave/oscillation width in Charpy V-notch (CVN) testing applications by restricting heat input and weld metal volume (see: Electrical Characteristics 9). Travel speed plays a key role in both those calculations, and weave width has a direct impact on travel speed (the wider the weave, the slower the weld progression, or travel).

With other processes, such as gas metal arc welding or flux-cored arc welding, weave width is governed by the "split layer" limitations of Table 3.6, Note e; the travel speed limitations of Table 4.5 (see: 18); and the heat input/volume limitations of Table 4.6 (see: 9).

Long story short, what you're looking for most likely will not come from a code book. Information may be available from the electrode manufacturer or found in the electrode specification (Example: A5.XX), but for the most part, determining maximum weave width comes from years of testing and trying.

During my time as a weld engineer, I've come up with weave width limitations that I have found to work in my applications. They were not limitations listed on a weld procedure specification (WPS) because of a code requirement, they were listed on the WPS because of the engineer’s requirement—my requirement.

I'm sure you came looking for a hard-and-fast number you could use to determine weave or oscillation width, but that is a number that you will need to calculate on your own with your specific process, electrode, and customer’s or manufacturer’s requirements in mind.