Not to overcomplicate things, pulsed MIG welding (also known as GMAW-P) is an arc welding process in which the wire electrode never touches the weld puddle. It is designed in to be a fast, efficient and spatterless process. All that is achieved thanks to Pulse sprayed transfer in which the power source switches 30-400 times per second between high peak current and low background current. During the peak current the welder pinches off a droplet of wire and propels it into the welding joint, at the same time the background current maintains the arc while it produces very low heat, that means the metal transfer can’t occur during this time, allowing the weld puddle to freeze faster and helping to prevent burn through.
Types of Parameter Functions
Synergic function: Means that you set the wire size, type and the material that you are going to weld, and the machine automatically adjusts the wire feed speed and voltage to start out with, which you can fine tune later yourself.
Non-synergic function: Means that you are going to have to set your wire feed speed and the machine will give you a reference number to where your power level should be. Similar to if you were setting up a voltage and a wire feed speed, only this time you are setting up the power level and the rest is adjusted by the software.
Uses of GMAW-P Method
The welding process was actually invented for industrial use, mainly to weld aluminum. As you know aluminum is thermally very conductive, meaning it would transfer heat away from the weld very fast, making the process extremely difficult and slow thus not efficient in terms of industrial production.
Pulse MIG welding has been used in industrial production for about 20 years, breaking into the handheld market no more than a decade ago, it can be used for multiple things. The most popular uses aside from manufacturing would be leak-tight welds like hydraulic cylinders, tanks and also pipes. Pulse technology offers a great alternative to TIG welding aluminum, silicon bronze, and stainless steel since it does not produce any spatter and is 3-4 times faster.
Pulse Spray Transfer Welding Advantages
- Reduced splatter
The spatter is reduced thanks to not having the actual end of the wire sticking into the puddle. With the arc length keeping you above it, there is less metal to be thrown out of the puddle. By reducing the amount of spatter, you can greatly reduce the amount of rework or post-weld operations like grinding and cleaning.
- Less heat input
It can reduce your heat input because the machine is cycling between a peak current and background current of voltage, which means that the machine is not continuously running on a high level current.
- Saving on wire and gas
Because it is possible to use same wire for different metal thicknesses with this particular method, the inventory cost would decrease. Same goes for the gas because it is possible to use the same gas mixture for multiple applications.
- Ease of use
Because of the synergic function, it is really easy to set up the machine, you only have to adjust one knob and you can start welding without too much
- Faster wire feed speeds/travel speeds
Pulsed MIG welding has very high deposition rate, and thanks to the possibility to set up the right parameters easily, you can start welding instantly.
What About the Price?
The professional machines are sometimes 5-10 times more expensive than regular wire feed welders and considering the applications it still quite expensive. After all, I think the equipment has to evolve to make it affordable to regular home hobbyists, though there are also cheaper alternatives on the market. If you are interested in buying a regular MIG machine take a look at this post as well.
GMAW-P is gaining traction right now, although it is really innovative and great process it is still out of the budget for a lot of people. Some folks even say that they are not using this option because the welder does somewhat scary noise.
Overall the pulse welding technology helps you to weld thin and thick materials, the best part is that helps to achieve better results and it is faster when it comes to welding stainless steel and aluminum.
If you are really interested in buying one, I would recommend you to take a look at Everlast PowerMTS 251Si. I would consider it to be the best option on the market.