Norstan's Electrical Contact Manufacturing Blog

Differences Between Spot Welding & Projection Welding

Website Team

The resistance welding process is commonly utilized in budget projects because it requires no additional materials outside of the metal that’s being joined.

Fortunately, the cost-effective nature of the process doesn’t translate to a less reliable weld. While differing welding methods vary in cost, the appropriate method is largely chosen by what is best suitable for the application.

Each type of welding has merit for particular types of jobs, including resistance welding.

Norstan offers our clients two varieties of resistance welding: spot and projection welding.

Projection welding is actually a modification of spot welding, the pioneer resistance welding process. Projection welding is generally used for projects with thicker materials (around 0.035” and thicker).

While it can be also used to join thinner metal pieces together, that tends to be a job left for spot welding.

Spot Welding

Spot welding typically joins metal sheets. It’s one of the oldest welding practices still in use today.

Using electrodes with pointed tips to create opposing forces allows pieces of metal to be heated and subsequently joined with ease.

The electrode shape used in this process determines the various weld factors, such as:

  • Current
  • Heat generation
  • Weld nugget size

The automotive industry relies heavily on spot welding when it comes time to join segments of automobile bodies and other large components. Other large items, such as household furniture and other domestic appliances and equipment are also frequently assembled using spot welding.

Spot welding is ideal for applications utilizing carbon steel and aluminum. In some cases, stainless steels, nickel alloys, and titanium can also be spot welded. The process also lends itself well to automation, which is seen as a notable benefit for many fabricators. Robots and manipulation systems can easily be programmed to perform spot welds.

The spot welding process offers manufacturers a range of advantages, including:

  • Affordability
  • Speed
  • Efficiency
  • Easily automated
  • Sheets as thin as 0.25” can be spot welded without issue

Projection Welding

Like spot welding, the projection welding process relies on heat generated by an electric current to join metal pieces together. Projection electrodes are capable of carrying more current than spot welding electrodes and can, therefore, weld much thicker materials.

During the projection welding process, two flat electrodes cover the face of a fastener. The projections themselves absorb and disperse heat, which allows strong welds with exceptional aesthetics to be produced.

Even contact and pressure between the fastener’s projections and the base metal helps avoid excessive electrode pressure.

The projection welding process is ideal for joining together metal components with embossments. It’s frequently utilized in electrical, automotive, and construction applications, in part due to the strength of the welds it creates.

Projection welding offers benefits such as:

  • A superior heat balance compared to other resistance welding methods
  • Ideal for scenarios requiring thick pieces of metal to be joined together

Welding Services at Norstan

Norstan offers clients both spot and projection welding services tailored to meet their individual needs. Our resistance welding services are ideal for those in the automotive, aerospace, and manufacturing industries, but can benefit any organization in need of strong welds.

Our team specializes in both spot and projection welding. With our knowledgeable, responsive staff at your side as you embark on your project, you’ll never need to worry about the quality of the parts or service you’ll receive. We’re fully committed to providing 100% customer satisfaction through innovative and attentive work.

A member of our team will be glad to speak with you about the specific requirements of your industry or application.

From there, we’ll work towards building an affordable, forward-thinking, and effective solution tailored to your project. If you’re interested in learning more about Norstan’s welding services, contact us today.