Due to a historically high rate of success, stud welding does not require the extensive testing that many welding processes do. However, a two-stud test performed by the stud welding operator is required at the beginning of each production period, whether at the beginning of a production run or at the start of a shift change. Testing should also be performed after equipment maintenance or when welding conditions may have otherwise changed.
Testing studs welded downhand to approved base plate materials
- Pre-production, weld two studs to a production weld plate according to pre-established welding procedure specifications.
- Visually inspect studs to determine a satisfactory weld.
- Bend each stud 30 degrees from the vertical using a pipe, hammer, or other bending device applied two in. (52 mm) above the stud weld.
*Satisfactory studs may be straightened to their original axis and using during production so long as they have not been heated during the process.
Testing threaded studs
After pre-production welding and visual inspection:
- Secure the threaded stud in an appropriately sized steel sleeve.
- Tighten a nut of the same material as the stud against a washer bearing on the sleeve with a torque wrench to apply a tensile load on the stud.
Testing studs at low temperatures
Impact testing, such as a blow with a hammer, should not be performed when studs or base plates are below 50°F (10°C). Instead, perform a tension test, bending the stud slowly with a tube.
Testing studs welded to non-approved base plate material or in alternative positions
- Pre-production, weld ten studs of each style and diameter to be used during production.
- Ensure that the positions, base materials, equipment, processes, etc. used during test weld replicates those found in the production environment.
- Visually inspect studs to determine a satisfactory weld.
- Test to failure by tensile, bend, or torque test, or a combination.
Naturally, a secure, reliable stud weld begins with secure, reliable studs and welding equipment. At PFSNO, we distribute everything needed to create ideal conditions for satisfactory welds. Contact our specialists to learn more today.
References:
Chambers, Harry A. “Principles and practices of stud welding.” PCI Journal 46.5 (2001): 46-59.
“Just the Facts: Destructive Testing of Stud Welds.” 2015. 15 Nov. 2015 <https://app.aws.org/itrends/2008/07/it200807/it0708-14.pdf>
