How does an electric welding machine work?
Electric welding is also known as manual arc welding and manual electric welding and is one of the oldest electric welding methods for metals.
Electric welding equipment
Electric welding machines work in such a way that an arc burns between the electrode and the workpiece, which supplies the energy required for the welding process. The high temperature of the arc melts the material at the joint. At the same time, the electrode melts as a filler material, whereby the type of electrode used depends on which materials are to be joined together, the extent to which the electrode is stressed and which welding power source is used.
Electrode protects against oxidation
On the packaging of the electrode it is marked for which positions the electrode is suitable, whether it works with direct or alternating current and how easy it is to handle. Nowadays, the rod electrodes are usually encased, and when this encapsulation melts, gases are produced which protect the arc and the joints from oxidation. Furthermore, slag is formed from the coating, which minimizes the surface tension and binds impurities.
Welding process with electric welding machines
When welding with an electric welding machine, the electrode is first clamped in a holder provided for this purpose and the arc is ignited by means of contact ignition, i.e. a short-circuit by briefly tapping the electrode on the material or by means of high-frequency ignition. Then the torch is guided to the welding point. The molten materials flow into each other during the welding process and solidify after cooling, creating the weld seam. Electric welding machines work with direct or alternating current.
Welding power source for electric welding machines
So-called welding transformers, welding units or welding inverters serve as welding power sources. The rule for electrofusion welding is that the thinner the material to be joined, the more expensive the welding equipment is, since thinner metals would burn through due to high current intensity during welding. In electrofusion welding, the electric arc burns between the melting electrode and the material.
Inverter welding machines
The very compact electric welding machines are relatively easy to handle. Since no shielding gas is required when welding with these devices, it is possible to weld even outdoors or in wind. Inverter welding units are also suitable for special electrodes and have particularly good welding properties. When welding with such devices, high frequencies ensure a very stable arc. For all electric welding machines it is essential that the electrodes are always stored in a dry place and that the temperature does not fall below the temperature when welding with an electric welding machine.