A WPS for GTAW, as well as one for GMAW allow both stringer and /or weave passes. Can anyone direct me to any restriction for the widthof a weave pass for either of these two processes, in either AWS or ASME codes?
Your help will be greatly appreciated.
QualityREP
(Studying for CWI July)
I understand that for both codes the maximum single pass allowed is 1/2".
Appreciate the resposnse. !/2" is the max weld pass depth or thickness allowed. My query was for face width. Thanks again. REP
AWS D1.1 - 2000 addresses maximum single pass layer width in Table 3.7. For GMAW / FCAW it is 5/8" for flat and 1" for vertical uphill. We require that the width of weave beads be no more than the diameter of the gas cup for GTAW. I am not aware of any formally written guidelines for GTAW.
Regards.
Is that for production or for a pre-qualified procedure. I don't have a D1.1 handy plus I'm not to hip on the D1.1 stuff as it seems to get thicker and thicker on each edition.
Thanks
Gerald Austin
http://www.geocities.com/pipewelder_1999/
In ASME 9, the definition of a "string" bead is a weld made without appreciable weaving. (or something to this effect) The bottom line being that this is such a wide open definition, that it is practically useless. We generally apply the principle that string bead welding is performed when the bead width is less than or equal to 3 times the electrode diameter. (e.g. If you use a 3mm diam. SMAW electrode, then anything narrower than 9mm would be considdered a string bead.)
Obviously, in the case of GMAW, this does not make a whole lot of sense because the elctrodes are so small in diameter.
I hope this helps.
Regards
Niekie
Thanks to all who replied. I like the answer citing Table 3-7 of D1.1.
This fits for my purpose.
A reason for restricting pass width could be limited to heat input limitations for the specific base metal. The cases that I have experienced with a "written specification" limiting bead width have been from manufacturers recommended practices for their material. An example would be welding Quenced and Tempered low alloy steel (A514 or similar). Excessive heat input can affect the properties of this material. The bead width on a ASME procedure is a non-essential variable for most processes. The bead width/heat input limits would be "pre-engineered" into the WPS and tested during the PQR welding. The limits of the WPS/PQR ranges both for ASME and AWS procedures do not always cover all of the things that need to be covered for a particular process/material/application.
In plain carbon steel in static loaded structures or piping without impact limitations I have heard many limits on bead width. I too am curios if there is any engineering reason to limit bead width on these type of materials. I am aware of qrain growth and reduced impact properties but is that always necessary to control?
Gerald Austin
http://www.geocities.com/pipewelder_1999/
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