Polarity and Current for Weld Fastening Systems

From ship building to composite thru-deck welding, stud welding is a simple operation used in many complex construction projects. The process of stud welding is a relatively new one, with a history dating only back to the turn of the 19th century. The newness of stud welding fastening systems is largely due to its use of electricity as a sole power source and arc generator. Because of this, the polarity and current supplied to a stud welding unit must be perfectly calibrated for the tool, stud, surface material, and weld circumstances.

 

If you are using stud welding to complete a project, you can rely on Northland Fastening Systems for all your studs, tools, accessories, and service needs. We provide a comprehensive selection of everything needed for stud weld fastening systems and expert technical support to customers worldwide.

 

If you are working with a stud welding unit and calibrating that tool for the weld you need, it’s important to understand the role of polarity and current for drawn arc and capacitor discharge (CD) welds.

 

Polarities

Every electrical current has a polarity that is either positive or negative. There are types of stud welding tools that use either polarity, but choosing which tool and polarity depends on the stud, the welding operation, and the surface material of what you will connect the stud to. Negative-electrode polarities are also referred to as “straight,” and positive-electrode polarities are also called “reverse” polarities. Positive polarities offer a weld with deeper penetration into the surface material. A reverse polarity weld is suitable for heavy-duty welding with larger studs. Negative polarities, on the other hand, offer a quick-melt weld with faster deposition rate, making it ideal for stud pins and rapid construction.

 

Currents

The pattern of electrical currents will also affect the weld results. Currents will move in negative or positive polarities directly or in alternating patterns between the two. Direct current (DC) welding paired with the correct shielding gas offers a smoother, cleaner weld thanks to a stable arc. DC welds also limit splatter in the weld. Because of this, most professionals use DC welding currents with either positive or negative polarities.

 

In some cases, however, alternating currents are more suitable. Beginners may choose AC welding tools that tend to be less expensive and easier to use. Alternating currents change polarities around 120 times per second with 60 hertz currents. AC welds are also used heavily in shipbuilding because the movement of the ship in construction may cause an arc to blow side-to-side.

 

Find the Right Fastening System Today

If you are using stud welding as one of your fastening systems in any given project, choosing the right polarity and current type is critical to performing an accurate, clean, and strong weld. To learn more about stud welding specifications or to find everything you need for studs, tools, and accessories, contact Northland Fastening Systems at (651) 730-7770, or request a quote online to get started with us today.

AC vs. DC Polarities in Stud Welding

Stud welding is a manufacturing application that is made possible by electricity. Before the development of electrical currents into various systems usable by individual consumers and businesses alike, the only format of welding possible was the ancient technique of forge welding. With the use of electrically generated currents, stud welders can create a bond between the stud and surface material that is stronger than either metals put together. If you are using stud welding on site, Northland Fastening Systems (NFS) can provide anything you might need, including welding studs, welding units for rent or purchase, and welding accessories for both drawn arc and CD stud welding.

 

When it comes to stud welding, there are two electrical current polarities that can be used depending on the welding situation and tools used: alternating current (AC) and direct current (DC). For the most part, DC polarities are used in almost every stud welding application. However, there are some instances when AC polarities are necessary and advantageous.

 

DC Polarities in Stud Welding

 

DC polarities move in what is essentially a straight line. The electrical current, whether positive or negative, flows directly from the power source through the tool and is applied at the weld site in either a capacitor discharge weld or a drawn arc current. DC welding is typically used because it provides a more controlled weld with a smoother arc that is stable and predictable. Positive DC welding performs a higher penetration into surface material for heavy-duty welding studs, while negative DC welding has a lighter penetration but greater deposition for effective welds on thin sheet metal.

 

AC Polarities in Stud Welding

 

AC polarities have a balanced transition between positive and negative direct currents throughout the application. Because of this, AC welding is beneficial over DC if you need lower penetration and an overall different type of weld. AC welding is a secondary option if the location of the worksite only offers that type of current, but it is also used in specialized welding processes such as welding magnetized materials. In addition, AC welding is used heavily in ship building, repairs, and other projects that need rapid, easily portable welding tools. However, AC welding often has a great splatter and is a messier weld than DC stud welding.

 

Learn More from Northland Fastening Systems

If you are using stud welding of any kind on your worksite, Northland Fastening Systems can help you determine whether AC or DC welding is a better option. For more information about polarities  or to find a comprehensive selection of equipment, contact us at (651) 730-7770. You can also request a quote online to get started with our team of expert technicians today.