Like in any manufacturing industry, diagnostics are critical for production utilizing stud welding in any capacity. Since its first use in the shipbuilding industry during the early 1900s, stud welding has expanded into many types of fabrication, from composite construction with shear connectors to thin insulation fasteners built into many structures. No matter what type of capacitor discharge (CD), drawn arc, or short cycle stud welding applications you work with, Northland Fastening Systems (NFS) has the supplies you need. Our selection of stud welding supplies includes tools for rent and purchase, studs in a comprehensive range of dimensions, custom stud options, welding accessories, and the expertise of our own staff technicians.
Stud welding operations can be complex, depending on the weld, stud, and material types. Because of this, results diagnostics are key to determine whether a weld process needs any adjustments. Even simple welds with pre-calibrated tools require basic testing to see if a connection point is strong.
Basic Testing
There are standard mechanical and visual diagnostics that can be done to check the first few welds after calibrating a tool for the dimensions, weld type, and surface material, including:
- Form two test welds to an approved base plate material sample.
- Inspect the weld to see if there are visible flaws such as spattering, burring, slag, and so on.
- Bend each test weld to a 30-degree angle from its vertical point. This bend can be done with a hammer, pipe, wrench, or other tool depending on the stud diameter.
- Inspect the weld connection to see if cracks or other flaws have appeared after the stud was bent.
- If no flaws appear and the test weld passes initial visual inspections, you can continue with that calibration for the rest of your job using those stud and base plate specifications.
Threaded Stud Testing
When using threaded studs, similar basic mechanical and visual tests can be done. Like the preceding weld tests, inspect two welds to an approved base material sample to see if visual flaws are apparent.
To perform a mechanical test for a threaded stud, set it in a secured steel sleeve. Then apply a tensile load by tightening a nut and washer down to the sleeve with a torque wrench.
Other Tests
When testing studs that must be attached to non-approved base plate materials, apply visual, tensile, and bend tests to at least 10 weld samples. These tests should be done until a stud failure. An accurate weld will see failure in the stud from metal fatigue, caused by repeat bend tests, rather than at the connection point.
Low-temperature welds can also be tested with a slow bend to 30ºF using a pipe. Impact tests are not useful when welding in low temperatures (50ºF or below).
Accurate testing can protect your final results from potential failure in any stud when applied in an assembly. To learn more about stud welding and the supplies and expertise we provide, contact NFS by calling (651) 730-7770 or requesting a quote online.