Ways to Weld Baskets: The Benefits of Medium Frequency Welding

October 29, 2014 | Robotic Manufacturing, Welding

As the years go by, techniques for achieving the best quality in manufactured goods continue to evolve as the tools we use become more sophisticated and precise. Centuries ago, if you wanted two pieces of metal joined, you’d need a hot forge, a hammer, and several hours of intense labor. After a time, the process of joining two metal objects evolved as new processes were discovered and experimented with. Today, we here at Marlin Steel wanted to talk about the process known as medium frequency direct current welding: what it is and the benefits of this welding process.

What Does Medium Frequency Direct Current Welding Mean?

Basically, medium frequency welding means that the welding machine uses a power inverter and semiconductors to increase the frequency of the current into the 1 kilohertz (kHz) range then processes it into a usable current through a welding transformer to apply direct current electricity at the welding point (this is a bit of an oversimplification of the process).

The key part of the above explanation, for most, is that an MFDC welder uses a power inverter to convert AC power into direct current for welding. This is the major difference between most 

standard electric welders and machines such as Marlin’s new automated welder.

What are the Benefits of Medium Frequency Welding?

The use of MFDC welding provides several key benefits when compared to standard AC welding, including:

1: Faster Weld Speeds


A typical AC welding machine can complete a weld in roughly 60 milliseconds, which is pretty quick when compared to the amount of time it takes a human to complete the same weld operation. However, a medium frequency welder can complete a weld in 2 milliseconds, roughly thirty times faster than an AC welder.

To put this in perspective, it takes about 100-400 milliseconds for the average human to blink.

2: Less Spatter and Other Deformities

As a side effect of the increased speed at which a medium frequency welder completes welds, there are fewer deformities in an MFDC weld than an AC weld.


This is because with less time spent on heating and joining the metals in a medium frequency weld, there is less of a chance for heat stress to occur. Heat stress from welding is the primary culprit behind the appearance of deformities in the weld.

3: Greater Strength of Welded Parts

With fewer deformities in the weld, the structural integrity of welded parts is improved and the useful life of the metal form is extended.

“How so,” you ask? By removing deformities in a weld, the shape of joined parts is more regular. This improves the ability of the part to meet exacting tolerances.

For example, say that you were making a custom wire form that needed to be welded. With the older AC machines, each individual piece of wire would have a variance of .5 degrees off-angle from weld deformities. Doesn’t sound like much, right? However, this minor variance from the tolerances set forth in the design could lead to increased strain on the part during operation, leading to premature failure. By reducing or eliminating this minor variance in each weld, the part will not be exposed to as much stress when in use.

4: Less Susceptibility to Power Fluctuations

Even in the most stable power grids, fluctuations happen. It’s a fact of life for manufacturers hooked up to an external power grid that the occasional fluctuation can cause issues for high-energy demand devices such as an automated electric welder.

However, a medium frequency welder is less susceptible to interruptions from power fluctuations because medium frequency welders have that power inverter that is so vital to their operation. When the power causes lights to flicker in the rest of the building, the power inverter’s stored charge is still available to the machine, meaning that a minor interruption in power won’t prevent the welder from completing a weld.

5: Less Power Consumption

When compared to a “normal” AC welder, a medium frequency welder uses up to 35% less power. The medium frequency welder achieves this heightened efficiency through the use of the power inverter.

How does the power inverter help increase energy efficiency? The welder’s power inverter draws balanced line current throughout all phases of a weld, making it less demanding on your power supply in comparison to a typical AC welder.

6: Improved Manufacturing Speed

When you combine the weld speed of the MFDC welding machine with the reduction of sharps, burrs, and other deformities in welded parts, as well as the enhanced operational stability of the welder, you get a significant overall increase in the speed at which custom metal forms can be processed.

This means faster delivery of custom wire baskets and other specialty metal forms.

Curious to see how Marlin Steel’s new medium frequency welder can enhance the production of your custom sheet metal and wire forms? Learn more by contacting Marlin Steel today.


Marlin Steel Ideal Welding Machine