Everything on electrode welding
How does it work?
Electrode welding is also called MMA welding (Manual Metal Arc) and arc welding with coated electrodes (BMBE). Typical of this welding technique is working with a melting electrode. You draw an electric arc between the workpiece and the electrode by striking it against the material, much as you would light a match. Then the electrode, which consists of a metal core wire and a coating (jacket), melts. The core wire is your welding additive material and the gases that are in the upholstery and released by the heat, ensure that you maintain the arc. Because of this you do not need a separate protective gas. The additive material melts on the workpiece and to protect the solidified weld material, a 'slag' is created. You remove it with a pitting hammer when it has cooled down.
When do you use it?
Electrode welding can be done, for example, if you make short welds. Your electrode melts after all, so if you have to weld large pieces, replacing your electrodes will considerably slow down the welding process. In addition, the removal of the slag takes extra time and this method of welding is less used for industrial purposes. But this welding technique can be performed in all positions, so that you also have a pipeline above your load or in hard-to-reach places in a weld construction to carry out repairs. In addition, this type of welding machine is ideally suited for mobile use, both indoors and outdoors.
What do you need?
Electrode welding is done with a welding machine that provides constant current. In addition to a suitable welding machine, you need coated electrodes to weld, which are available in different diameters. Each welding machine is suitable for electrodes up to a certain size, for example from 2 to 4 millimeters. In addition, the coating of electrodes can be divided into 3 main groups: rutile, basic and cellulose. In a nutshell:
Electrodes with a ** rutile ** coating are most commonly used and there are several reasons for this. This way you read with this electrode in every position, you make strong welds and there are relatively few splashes. You use these electrodes for unalloyed steel. Welding with ** basic ** electrodes ensures that the welded joint is strong and has a low degree of brittleness. The weldability of these electrodes is less good than that of rutile electrodes. You make coarser welds with it and the slag is harder to remove. If you are going to weld low-alloy steel, then basic electrodes are the best choice. ** Cellulose ** electrodes cause a lot of smoke and splashes during welding due to the high cellulose content in the coating. This is not ideal, but on the other hand, you will suffer quickly, in all positions. The weld is also deep and less susceptible to corrosion. Electrodes with this coating are widely used in the welding of pipelines together.
Many electrodes are a combination of the above coatings and the associated fabrics, because they all have their advantages and disadvantages. If you get started with coated electrodes, it is crucial that the upholstery is not damaged and the electrodes are not damp. This has a big influence on welding. Electrodes are for that reason available in vacuum packaging, so that they remain well preserved. Once the package is open, store the electrodes in a dry room.
Which materials can you weld with it?
Which materials you are going to weld depends on the type of coating on your electrode. Basically you can connect any type of material with electrode welding, except aluminum. However, it is important which type of electrode you use. For example, to weld cast iron you use a different kind of electrode than when you connect stainless steel, or just two different materials. The thickness of the material that you are going to weld is also something to be reckoned with. Electrode welding is less suitable for thin plates, because it is rather a rough way of welding and you run the risk of burning the material.
What are the advantages?
As mentioned, electrode welding is a welding technique that is both popular with the freelancer and the do-it-yourselfer. It is no coincidence that electrodes can also be purchased in small packages, ideal for the af-and-toe welders. For a professional, electrode welding is ideal for carrying out small repair and construction jobs. Due to the absence of protective gas it is good to use in the open air. The required welding machine is compact and light, so that the freelancer can easily dispose of it in his bus and the do-it-yourselfer in the shed. An additional advantage is the relatively low cost of the equipment and the fact that there is little damage to this type of welding machine, so that it is certainly an attractive welding technique for the starting welder to start with.