I welcome everyone to our channel, which we conduct for all self-taught beginners in welding and locksmiths. Whoever tried to weld something at least once knows that the metal is deformed after welding. Let's see why this is happening.
Let's start with a simple analogy, which I showed in an old article about welding tacks. Here we have taken a certain amount of snow. Now we blind a round dense snow. The finished snowball will be smaller than the original handful of snow.
The same will happen with the tack weld and the weld seam. As soon as it starts to cool down, it will sharply decrease in volume.
Remember at school in physics class there was such an experience with heating a coin. Cold, she calmly walked between 2 nails driven into a piece of wood. And after heating, it could not pass, from heating the solid expanded and became larger in volume. And with the weld, the opposite will be true, it decreases as it cools.
This means that there will be movement in the heat-affected zone, and this force will affect the entire welded structure as a whole. When the weld cools down, it shrinks and begins to pull together the heat-affected areas of the metal, these areas, in turn, pull more distant areas towards themselves. The simplest analogy, see.
Let's imagine a butterfly. Let her long body be the welding seam, and let her wings be the workpieces that we welded! As soon as the seam begins to cool down, the workpieces should move to the side, as if the butterfly would raise its wings a little.
For the experiment, I will take a piece of a profile pipe and put several seams right on the surface of one of the shelves. As soon as the seams begin to cool, the profile pipe will bend slightly at the edges towards the seams. Everything is like a butterfly analogy! The surface opposite to the seams will become a slightly curved arc.
These physical laws need to be known and always taken into account when welding metal structures. This is an introductory article, in which we will not analyze examples of dealing with deformations, we will do this in other publications.
I hope with simple examples it turned out to clarify this point for self-taught beginners in welding. Until next time!