Folks, Hello .Prodolzhaem toss useful articles to our blog welding. And now let us look at a fairly simple, but very important stuff (well, as little things, the big welding school can get without it), but what you need to finish the welding seam correctly? When we perform the welding, the following process takes place - arc instantly heats the surface of the base metal and the obtained point of the molten liquid metal. The arc is at this point carries the molten metal from the electrode to this point as the molten metal at the welded surface. His flow of metal from the electrode to the weld pool arc creates pressure which, in place of the arc and the contact forms a recess bath called crater. Represent faucet in our kitchen, and if you open it harder (to make a lot of pressure) and bring a cup and pour water, then place water jet and water contact surface a small indentation appears in a glass - that's just as well and with welding, but very hot !
And when we cook a little longer weld and dramatically remove the arc at the end of the seam is formed and it is the recess called a crater. So leave in any case can not be - a violation of welding technology, there is obtained a reduction seam section, and thus decreases the strength of the weld joint. Therefore, in such a weld crack can be formed, and this weld joint collapses.
Therefore, we always need to brew this crater. That is, at the end of the weld does not remove the sharp arc and slowly lengthen the arc to break it - at this moment is filled with metal crater. That's it, now our welding seam is welded on the right technology and without jambs! You can also go back to 1 1.5 cm (already laid seam) and here to break the arc, and the crater will be. Or at the end of the joint strike several times in one point for zaplavki crater (I'm doing just that - a habit).