Shear studs are everywhere in composite steel framing—headed anchor rods welded through deck or directly to beam flanges, transferring shear between the concrete slab and the steel beam to create composite action. Despite their ubiquity, stud welding qualification is one of the more frequently misunderstood requirements in structural fabrication and erection. AWS D1.1:2025 Section 8 governs stud welding, and its requirements differ materially from the groove and fillet weld provisions that occupy most of the code.
Rule library based on AWS D1.1:2025; verify against your governing edition (the AHJ or contract may specify 2020 or earlier).
What Section 8 Covers—and What It Doesn't
AWS D1.1 Section 8 applies to stud welding using the drawn arc stud welding process: a stud gun that lifts the stud, strikes an arc, and then plunges the stud into the molten pool under spring pressure. This process is used for headed shear studs (Nelson-type or equivalent) for composite construction, as well as other stud-type fasteners.
Section 8 does not apply to resistance-welded studs (a different process used for thin sheet applications) or to standard structural welds on stud baseplates. The moment a crew picks up a stud gun on a structural job, Section 8 controls—regardless of whether the stud is for composite floor framing, a concrete embedment, or a headed anchor in a base plate connection.
Why Stud Welding Cannot Be Prequalified
The prequalified WPS provisions in AWS D1.1 rely on decades of research establishing that certain joint geometries, processes, and base metals produce reliable welds within a defined parameter range without requiring a test weld every time. That confidence does not extend to stud welding because the process is highly equipment-sensitive. The drawn arc stud gun's lift height, arc time, plunge force, and ferrule condition all affect weld quality—and these variables interact with the specific stud size, flux load, base metal composition, and surface condition in ways that are not fully predictable from tabulated parameters alone.
As a result, every new combination of stud size, base metal, and welding equipment must be qualified by pre-production testing before production begins.
Pre-Production Qualification Testing
Pre-production qualification under AWS D1.1:2025 Section 8 requires welding a minimum of four test studs under the same conditions—same equipment, same settings, same base metal, same stud diameter and length, same position—that will be used in production. If studs will be welded through deck, the test must be done through deck of the same profile and gauge.
After welding, each test stud must be bent to at least 30° from vertical using a ring, collar, or suitable bending tool. The bend direction should simulate what a failing stud would experience in service. The acceptance criterion is simple: no cracking in the weld or heat-affected zone after bending to 30°. Visual inspection of the weld base (the "flash" formed by the molten pool) should also show a full 360° ring of weld flash, indicating complete fusion around the stud perimeter.
If any test stud fails, the welding parameters must be adjusted—typically arc time (which controls heat input), gun lift height, or stud flux condition—and four more studs must be welded and tested. This cycle repeats until four consecutive studs pass.
Document the qualified parameters: amperage, arc time, lift height, shielding (if used), and the ferrule part number for the stud size. That documentation becomes the project's stud welding procedure.
Essential Variables for Stud Welding
Although stud welding procedures cannot be prequalified, the essential variables that require re-qualification when changed are defined in Section 8. Key variables include:
Stud diameter. A procedure qualified on 3/4 in (19 mm) studs does not automatically cover 7/8 in (22 mm) studs. Heat input and arc dynamics differ with stud diameter, and each size requires its own qualification.
Base metal specification. Changing from A36 to A572 Grade 50, or adding a weathering steel, requires re-qualification even if the yield strengths are similar. Composition affects how the HAZ responds to the arc.
Welding through deck versus direct-to-flange. Qualifying direct-to-flange does not cover through-deck welding and vice versa. The deck profile, its galvanizing or coating, and the additional heat demand of burning through the deck are all process variables.
Stud gun type and model. Different stud gun models have different arc characteristics. If the contractor changes gun manufacturer or model mid-project, re-qualification is required.
Welding position. In structural erection, studs are most commonly welded in the flat position (1G). If any studs will be welded in another position—for example, overhead on transfer beams—a separate procedure qualified in that position is required.