Does arc stud welding require a WPS?

Yes, but the format differs from a groove or fillet weld WPS. AWS D1.1 Clause 7 requires a stud welding procedure that specifies stud type, base metal, power source settings, ferrule type, and technique. It's typically documented on a separate form from an Annex M WPS.

What are the pre-production weld tests for studs?

Before production welding begins each shift, the welder makes test welds on a separate plate of matching base metal and passes a bend test or torque test. For headed shear studs, two test studs are bent to 30° from vertical — they must show no cracks in the weld or HAZ to pass.

Does AISC 360 composite design specify stud installation requirements?

AISC 360 references AWS D1.1 Clause 7 for stud installation. The structural engineer of record sizes the studs for composite action; the CWI and fabricator ensure the installation procedure and pre-production qualification match Clause 7.

Can studs be welded through deck in the field?

Yes. Through-deck welding is addressed in AWS D1.1 Clause 7 and is the standard method on composite floor systems. It introduces additional technique requirements — longer weld cycle to burn through the galvanized deck, minimum embedment through the deck panel, and often higher power settings than direct-to-beam welding.

Stud welding under AWS D1.1: WPS and qualification basics

Arc stud welding for composite deck follows AWS D1.1 Clause 7, not the process chapters. Here's what qualifies the procedure and what production tests to run.

Arc stud welding (ASW) is the process behind the headed shear studs used in composite steel-deck floor systems. If you've watched field crews fire a stud gun into a beam flange through galvanized deck — that's AWS D1.1 Clause 7 work. The WPS and qualification requirements are entirely separate from the groove-weld and fillet-weld process chapters, and audit reviews of stud packages frequently find thinner documentation than for any other weld type on a project.

What Clause 7 covers

AWS D1.1 Clause 7 governs the design and welding of steel studs to a structural steel base. The primary application is shear connectors for composite construction — headed studs welded to the top flange of a steel beam, subsequently embedded in concrete poured over metal deck.

Clause 7 addresses:

Stud base material (ASTM A108 is the dominant specification for headed shear connectors)
Ferrule (arc shield) requirements and their role in shaping the molten pool
Equipment qualification — power source, stud-welding controller, stud gun
Pre-production qualification tests before each shift or after process changes
Post-weld visual inspection criteria and bend testing for production acceptance
Geometric requirements: head diameter, shank diameter, overall height after welding

The main process chapters — and the essential variable tables in Section 6 — do not apply to arc stud welding. There is no Table 6.6 essential-variable analysis for studs. The qualification framework is purpose-built for the stud process.

The stud welding procedure document

A stud welding procedure must specify, at minimum:

Stud type and geometry. Manufacturer, nominal shank diameter, head diameter, and length before welding. Standard headed shear studs for composite construction are most commonly 3/4 in diameter. The overall height after welding determines composite capacity and cover requirements.

Base metal. ASTM designation, minimum yield strength, and thickness. A procedure qualified on A36 plate may not cover A992 wide-flange flanges if the flange thickness falls outside the qualified range.

Power source and controller settings. Lift height (the distance the stud is drawn away from the base at arc initiation), plunge depth, weld current in amperes, and arc duration in milliseconds. These are the primary variables that control heat input and pool penetration. Changes to these settings beyond the procedure's qualified range require retesting.

Ferrule type. Ceramic ferrules are single-use and must match the stud diameter and application type. Through-deck applications use a different ferrule geometry than direct-to-beam applications.

Technique. Stud gun angle, surface condition (clean mill scale, primed, galvanized deck), and whether the weld is direct-to-beam or through-deck.

Unlike an Annex M WPS, the stud procedure document is compact — often a single page — but it must be on file, signed by a responsible engineer or CWI, and available on the job site for the inspector.

Pre-production qualification tests

Before the first stud goes on a production member, Clause 7 requires pre-production testing. The purpose is to verify that the equipment, power settings, and technique produce sound welds on the actual base metal used that day. This is separate from the initial procedure qualification — it happens before every shift.

Bend test (headed shear studs). Weld two test studs to a separate test plate of matching base metal. Bend each stud to 30° from vertical using a bar or tube against the shank. Examine the weld fillet and HAZ after bending. Cracks or separations in the weld or base metal are a failure. No cracks after bending to 30° is a pass.

Torque test (alternative for threaded studs). Torque the stud to the manufacturer's specified value; acceptance is no rotation or fracture. More common for threaded insert studs than for headed shear connectors.

Frequency. Tests are required at the start of each shift, whenever the stud lot number changes, whenever the base metal heat changes, whenever power settings are adjusted, and whenever the operator changes. A new operator on the same equipment still needs to run test welds.

The pre-production test is the most commonly skipped item in a stud-weld audit. On a composite deck floor, a crew may weld 500–800 studs per shift. The pressure to skip the 15-minute test is real. A CWI should witness or verify the test plate before production starts and retain the bent test specimens or a photograph in the job record.

Through-deck welding

Through-deck welding is the dominant technique on composite floor systems. The stud is fired through a pre-punched or power-tool-pierced hole in the galvanized steel deck, fusing to the beam flange below.

Key requirements that differ from direct-to-beam welding:

Longer arc duration and higher current. The arc must burn through the deck material and galvanized coating before fusing to the beam flange. Power settings for through-deck welding are typically higher than for direct-to-beam, and the procedure must reflect the specific deck profile and thickness.

Embedment. The stud shank must penetrate fully through the deck and achieve fusion to the beam flange. After welding, the weld fillet at the base of the stud should be visible above the deck surface on the stud perimeter. An incomplete weld that fuses only to the deck panel — not to the beam — is a structural failure.

Deck tab and ferrule position. Some deck profiles trap the ferrule or misalign the gun. The procedure should specify the ferrule seating method for the specific deck profile used.

Production inspection

Post-weld visual inspection of stud welds examines:

Weld fillet continuity. A full 360° fillet is required at the stud base. Stud welding produces a characteristic flash or collar around the full perimeter — gaps in the collar, porosity visible in the fillet, or incomplete fusion at the base are rejections.

Stud verticality. Studs tilted more than 5° from vertical are typically rejected. Excessive lean affects concrete load transfer regardless of weld quality.

Stud height. After welding, the stud loses approximately 1/4 in of its pre-weld length as the tip burns off and the molten pool forms. Heights outside the specified range indicate a process problem.

Studs that fail visual inspection are replaced. Replacement procedure: cut or break the stud at the base, grind the weld area flush, verify the base metal surface condition, and re-weld per procedure. Avoid prying — prying at a failed stud can raise a notch in the flange that is harder to repair than the stud itself.

Common documentation gaps

CWIs reviewing stud-weld packages regularly find:

No pre-production test records for daily shift starts
Power settings on the procedure don't match the controller settings the crew actually used
No procedure document — the foreman set up the gun from memory and a prior job's settings
Through-deck procedures cited for a direct-to-beam application, or vice versa

A maintained stud welding procedure, shift-by-shift pre-production test logs, and a straightforward production inspection record satisfy most owner and AISC certification audits. The documentation overhead is lighter than a full test-plate PQR package, but it still requires a system.

For how stud welding fits within a broader procedure library covering SMAW, GMAW, and other processes, see how to write an AWS D1.1 WPS and welding procedure library, audit-ready. For a platform that manages all procedure types in one place, see pricing.

Rule library based on AWS D1.1:2025; verify against your governing edition.