Smoke, bright lights and crackles. All this will accompany metal welding with an electrode. Smoke and light is understandable, but why do the electrodes crack during welding? It's all about the process that takes place between the end of the electrode and the metal to be welded.
The metal from the electrode flows into the weld pool in the form of drops. When we strike the electrode against the metal, a short circuit occurs. Here we raise the electrode slightly from the metal. At this moment, a drop of molten metal is formed, in shape it looks like a pear.
The drop increases, the neck becomes thinner, and the drop is detached and transferred to the weld pool. Next, other drops of molten metal appear, break off and flow into the weld pool.
This process will make a certain sound. When the tap is not completely closed, the drops of water will knock on the sink and bother us with it until we deign to get up from the sofa and close the valve. Everything is the same with welding.
The contact of metal droplets that fly from the electrode and the molten pool of the weld pool will be clearly audible. We will hear this crackling when welding. And there will also be splashes of molten metal, they will scatter on the sides of the weld pool. Therefore, next to the seam, we see many small drops of frozen metal.
From 20 to 50 drops of molten metal are transferred per second, they can be of different sizes. The transfer is small-droplet and large-droplet. The more often and finer the droplets are transferred to the weld pool, the higher the weld quality will be.
This sound can be used to compare the quality of electrodes and welding machines. The more the crackling turns into a uniform hiss, the better the electrodes or welding machine. This means that there is a fast small-drop transfer, there will be less spray, the quality of the seam will be higher. You will try to observe and compare.