Month: December 2019

Avoiding Common Defects with CD Stud Welding

Posted on by norfas by norfas

Stud welding is an operation that many industries utilize because of its diverse benefits to a wide range of production processes. While drawn arc stud welding is key for heavy-duty studs, load-bearing composite building, and other large-scale construction, CD stud welding has an equal frequency of use in different types of construction.

 

If you’re using CD stud welding in your production process, you will gain the benefits of rapid, economical, low-energy welding that provides a clean weld with no reverse-side marking. With the help of Northland Fastening Systems technical support and our selection of all the tools, studs, pins, and accessories you might need for CD stud welding, you can get your job done with ease and quality.

 

CD stud welding is a form of resistance welding, unlike drawn arc welding. Arc welding is a fusion welding process that often requires a filler material and frequently leaves a slag from the flux used that has to be cleaned to finish the product. CD stud welding doesn’t require a filler material and it leaves a clean weld that won’t need finishing after the weld is done.

 

When done correctly, CD stud welding is a fast and easy process that leaves a pristine, strong weld. However, there are some defects that can occur when CD stud welding is not performed accurately or with the right materials:

 

  • Spread of molten metal from the weld site is a common issue when weld pressure is too low, the current is too high, or the weld is timed incorrectly. Molten metal expulsion can also be evidence of surface contamination.
  • Spattering of metal is another sign of too high a current. It creates excess heat that can cause explosive spray and loss of metal at the weld site, weakening the weld overall.
  • Cracked weld connections are a clear alert to a weak weld. These cracks often occur due to lack of pressure during the weld leading to an incomplete or porous connection. Inadequate pressure during the weld leads to a low tensile strength at the connection point.
  • Indentations at the weld site are another result of incorrect pressure and/or current. With too much pressure, the current decreases and a poor weld connection is formed because of the low pressure. Welding studs indented into surface material even slightly are a sign of too high of pressure and too low of current/temperature.
  • Misshapen weld spots are also a common defect with incorrectly performed CD stud welding. A strong, accurate weld should have a perfectly circular weld mark. Bloated, smushed, or otherwise misshapen weld spots are a result of contamination or misaligned electrodes in the welding tool.

 

These defects can be easily avoided when you choose to work with NFS products and take advantage of our technicians’ expertise whenever questions arise. To learn more about our CD stud welding products and other stud welding supplies, contact NFS at (651) 730-7770 today. Request a quote online to get started on your stud welding project now.

 

Glossary of Terms for Stud Welding

Posted on by norfas by norfas

For any builders, fabricators, or manufacturers who are just beginning to use stud welding operations as a tool in their work, there is a lot to learn. While stud welding appears to be a relatively simple, straightforward operation, there are many complexities about the varying types of processes. At Northland Fastening Systems, we offer a comprehensive supply of stud welding tools, studs, and accessories in addition to our expert technical support services. If you are a beginner or even an experienced stud welder, our team of skilled service technicians can provide the support and tools that you need to get the job done.

 

If you are just beginning to work with stud welding tools and processes, it’s important to understand the basic terms used to describe aspects of the operation. Some of the most important, widely used terms in the stud welding industry include:

 

  1. Stud: Any fastener used in the stud welding process. This includes pins, shear connectors, and bar anchors as well as standard studs. Studs can be made from steel, aluminum, brass, copper, or related alloys.
  2. Gun: The hand-operated tool used by the technician performing the weld. Studs are inserted in the tip of the gun and applied to the surface that it will be welded to.
  3. Controller: The electrical unit controlling the supply of voltage to the welding gun or welding tip. The controller used depends on the type of welding process, the stud dimensions, and the material to be welded to.
  4. Parent material: The surface material that the stud will be welded to. This is also called the “workpiece.” If done correctly, the bond between the stud and the parent material will be much stronger than the stud or parent material alone.
  5. Capacitor discharge (CD): A type of stud welding process that uses electrical discharge heat to connect the stud to the parent material. CD stud welding is fast, cost-effective, and clean.
  6. Drawn arc: Another common type of stud welding. The process uses an arcing current to heat the stud inside a ceramic ferrule while it is held against the parent material. This process is suited for welding heavy-duty studs with larger diameters.
  7. Ceramic ferrule: A ceramic containment piece for the stud used in a drawn arc process. It serves to regulate the weld temperature and prevent the molten metal from moving outside a desired range.
  8. Chuck: A component that holds a stud in the tip of the welding gun during the CD stud welding process.
  9. Flux: An aluminum coating on the tip of a drawn arc welding stud. It improves the ignition and de-oxidizes the pooling of the weld point.

 

There are many other terms used for different components of various welding processes, but this list covers the basic vocabulary used in most stud welding operations. To learn more about stud welding and the tools or terms used, contact Northland Fastening Systems at (651) 730-7770 or request a quote online today.

 

 

 

 

 

Application of Shear Connectors in Thru-Deck Stud Welding

Posted on by norfas by norfas

Stud welding is a versatile process with many industrial applications. While stud welding is often primarily used in exterior or visible interior installations, it is also a key operation for large-scale construction. Shear connectors and other anchor bar systems provide necessary strengthening of a structure and critical support against stresses. If you are fabricating a system with metal decking or other weld-thru metal structures, Northland Fastening Systems (NFS) can provide the shear connectors, anchor bars, welding tools, and any other studs or accessories you need to get the job done. When it comes to thru-deck stud welding operations, NFS offers the technical support and tools needed.

 

Composite construction applications like thru-deck welding requires careful consideration of each material used in the process and understanding of the process itself. When it comes to the composite building of structural beams, galvanized decking, and concrete, shear connectors welding studs are key for long-term structural integrity.

 

The included image shows a three-dimensional cross section of a weld-thru decking application. The shear connecter studs welded directly through the galvanized decking material fasten it to steel I-beams. A rebar webbing is overlaid for support and flexibility of the final layer of concrete finishing the composite system. As a complete decking system, this composite structure can be utilized in a range of applications, but is primarily used in the construction of multilevel buildings with steel beam skeletons.

 

The use of shear connector welding studs is critical in this type of composite construction system. If you are working with thru-deck weld construction processes, NFS can provide comprehensive shear connectors in varying dimensions, including stud diameter and length.

 

For general-purpose thru-deck composite welding, our shear connector studs have a minimum tensile strength of 61,000 psi (420 MPa) and a minimum yield strength of 49,000 psi (340 MPa). For shear connectors that will be used in composite beam construction like the processes used in multilevel buildings, our specialized studs have a minimum tensile strength of 65,000 psi (450 MPa) and a minimum yield strength of 51,000 psi (350 MPa). NFS also offers custom lengths for both types of shear connectors with any of our available diameter.

 

Not only do the connector studs fasten galvanized decking to structural beams, they are also key in shear load bearing. The minimum tensile and yield strength of each stud works together to support entire buildings upward of 100 stories. The system of a composite beam construction increases the flex range and support strength of the building as a whole, which allows it to react to movements of the earth plates, the wind, and other natural elements; weight inside the building; and changes in molecular size with temperature shifts. In every composite structure, shear connectors are key components.

 

To learn more about weld-thru decking and the use of stud welding in composite construction, contact NFS at (651) 730-7770 today, or request a quote online to get started with us today.