CEMP-E
TI 809-26
1 March 2000
CHAPTER 6
STUD WELDING
1. GENERAL.
Stud welding for building applications is generally for shear connectors in composite beams, but may
also include shear connector applications for composite columns and frames. Studs may be welded
either directly to the structural steel or through metal decking. The purpose of most shear connectors is
to integrally connect steel and concrete materials so that they act as a single unit in resisting load.
Occasionally, threaded studs may be used for special connections where bolting is not practical, such as
embedment plates or inaccessible connections. Stud welding is a fully automated process with controlled
arc length and arc time, and is conducive to a suitable convenient load test, and therefore is treated
separately by AWS D1.1 for procedure qualification, personnel qualification, and inspection.
2. STUD WELDING PROCESS.
The arc stud welding process is used for structural studs, rather than the capacitor discharge stud
welding process. A DCEN (straight) current is used to create an arc between the stud base and the steel.
The stud welding gun draws the stud away from the steel, creating the arc, allows a brief period for the
melting of the steel and stud base, then plunges the stud into the molten pool and terminates the current
flow. The weld arc and molten pool is protected with the use of a flux tip on the base of the stud, plus the
use of a ceramic ferrule to contain the molten pool. See AWS C5.4, Recommended Practice for Stud
Welding, for complete information.
3. STUD BASE QUALIFICATION.
Stud bases are qualified by the manufacturer for application on bare steel in the flat position only.
Qualification procedures for this application are provided in AWS D1.1 Annex IX. For all other
applications, including studs applied through metal decking, studs applied to curved surfaces, studs
welded in vertical or overhead positions, or studs welded to steels not listed as Group I or II in AWS D1.1
Table 3.1, the contractor must perform qualification testing. For the Type B studs used in composite
construction, ten (10) specimens must pass a 90o bend test using representative material and
application. Alternatively, a tension test method may be used. See AWS D1.1 Section 7.6.
4. WELDING PERSONNEL QUALIFICATION.
The welding operator conducting the two pre-production tests at the start of the day or work shift is
qualified for performing stud welding that day or shift. See AWS D1.1 Section 7.7.4.
5. PRE-PRODUCTION TESTING.
After stud base qualification by the manufacturer, or qualification testing by the contractor for the
applications listed, installation may begin. However, pre-production testing is required at the start of each
day or shift to verify the setup of the equipment. This testing requires two studs to be welded, on the
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