AWS doesn't limit the size of single pass fillets based on electrode diameter. The size is limited by position, with an exception for single pass wels on bare, unpainted weathering steel exposed to the weather.
In addition, there is no restriction when using a WPS qualified by CJP groove, as the limitations of Clause 3 are not invoked. If qualifying through separate fillet weld test, it's based on the size established by the maximum single pass fillet portion of the qualification.
One thing many people do not take into account when discussing weld sizes is the travel speed range. Regardless of what size is deposited, if the welder is operating outside the travel speed range then it is a moot point.
If the WPS is qualified by testing, the travel speed recorded is one of the variables recorded. If the applicable AWS D1 code is D1.2 as an example, the WPS can increase or decrease the travel speed by 20 percent before the WPS must be requalified. The change in travel speed will affect the fillet weld size. Still, the maximum size of the single pass fillet weld is limited by the weld deposited and recorded by the PQR.
The same limitation is not impose on prequalified WPSs. As stated previously, when using prequalified WPSs, the maximum fillet weld size limitation only comes into play along the edge of a lap joint in all of the AWS D1.X weldng codes.
