There are many types of electric welding. There are transformer inverters and simple rectifiers. But the most simple to work is the inverter. It is most often used both in everyday life, and in construction, and in production. Each owner of this device wants to know how to learn how to weld metal using inverter welding. The technology itself is not very complicated and consists of a series of actions.
Scheme of gas welding metal.
The more accurately you follow the sequence, the better the seam will be. Reliable metal welding is a quality connection of two metal surfaces.
Preparations for welding
First you need to carefully prepare the place in which the metal will be welded. There should not be flammable objects nearby: plastic, wood, paper, cardboard, polyethylene, fuels and lubricants. When welding works, an arc is formed, many sparks occur, which can cause ignition. The welding machine must be securely installed on the ground or concrete base. After that, the power cord is plugged into the outlet. The plus pin has a crocodile tip by default. It connects to the metal that needs to be welded. On the negative wire is a device for fixing the electrode.
You need to prepare yourself for the work. First of all, there must be good equipment. The whole body must be protected from the chance of sparks and hot metal.
Scheme of the electric welding apparatus.
Gaiters are gloves that withstand high temperatures. They close their hands almost to the elbow. It is advisable to use them when welding metal. Boots are required to protect the feet, it is not recommended to put on shoes in flip-flops. They are made of synthetic materials that very strongly burn the skin. Jacket and pants must be made of thick material that does not burn well. Of course, many do not have the opportunity to purchase good equipment, which is used by professional welders. Therefore, denim clothes fit perfectly. It is simple and accessible to all.
For beginners, the chameleon mask will be very convenient. In it the light filter is designed so that in daylight it is as transparent as possible. And with increasing brightness (when the arc ignites), the glass darkens. To put it simply, you do not have to constantly raise the mask. This means that you will get to the place of welding with high accuracy. Then install the electrode in the terminal and, without releasing it from your hands, turn on the toggle switch. Usually it is on the back panel, and when turned on, it lights up a red lamp. The welding current is regulated by a potentiometer located on the front panel of the inverter. In everyday life, electrodes are most often used, whose diameter is 3 mm. For it is necessary to establish a current of about 100 A. Now you can start to start welding the metal.Back to table of contents
How to ignite the arc?
The classification of the arc.
The most difficult thing for beginners is to start an arc. That it allows welding two surfaces. The more experience you have, the easier it will be to start the arc. But in the initial stages there will be some difficulties. The electrode may stick or, on the contrary, will not ignite. A lot of time will pass before the moment when you get the required arc. First you need to knock the electrode on the metal to remove the plaster from its end. In order for an arc to appear on a cold metal, it is necessary to make movements with an electrode, as if striking a match across a box. It should not be strongly pressed to the surface, only a light touch is allowed.
The likelihood of the electrode sticking is high. Therefore, you need a sharp movement to tilt the handle with it and break off the rod from the welded surface. If it is impossible to tear it off, it is necessary to de-energize the apparatus, after which the electrode is easily separated from the metal. Strike the strike until a bright arc appears, which can only be viewed through tinted glass. Even the use of sunglasses will not help, so do not experiment. In order for the arc to continue to burn, it is necessary to hold the electrode at a distance of 3.5 mm from the metal surface. At first, this will be problematic, but over time you will get used to it. Do not forget that you can make two mistakes in the process:
The main types of trajectories of transverse vibrations in arc welding.
- reduce the distance between the electrode and the metal, resulting in a short circuit, and the electrode will stick to the surface;
- increase the distance, as a result of which the arc disappears and it will have to be re-ignited.
When conducting metal welding, the electrode decreases, as its core (metal part) fills the weld, and the outer part (plastering) gradually burns out. Your hand should move slowly, but evenly, toward the surface being welded.Back to table of contents
Welds and bath, selection of welding current and polarity
As soon as you start the electric arc, a puddle of molten metal will immediately appear on the welded surface. It is called a bathroom. During work, the edge of the electrode should be moved as slowly as possible between the surfaces being welded. Immediately after the end of the electrode is a bath. To improve the quality of the seam, it is necessary to make the movement of the electrode. Their options can be many.
The movement of the electrode can be carried out both left and right, and spiral, zigzag, herringbone, arc. As a result, your seam will turn out as strong as possible, the metal will melt deeply. From the speed with which the movement of the electrode takes place, the characteristics of the seam depend:
Types of welds.
Greater movement speed means less depth and bulge. But the seam is smooth and very narrow. If you move slowly, then the depth increases, as well as the bulge. Consequently, the strength of the connection also increases.
If you weld metal surfaces with electric welding and remove the electrode at the end of the seam, a crater is formed.
To avoid this, you need to briefly hold it at the end. Molten metal will accumulate in this place. Do not forget that the quality of the seam is directly dependent on the position of the electrode. It should be strictly at right angles. But a deviation of no more than 20 ° is permissible.
For a start, it is better to practice by swiping them left and right along metal surfaces. With the loss of the electric arc, it will be much easier to re-ignite it, since the metal is still hot. As soon as the length of the electrode is reduced to 5 cm, it should be replaced. It is desirable to turn off the welding machine. As soon as you finish the work, you need to tap the seam with a hammer so that all the slag crumbles.
From the current directly depends on the depth at which the metal will be melted. The higher its value, the deeper the surface will be melted. To melt horizontal surfaces, it is necessary to select the maximum current. If metal is being welded on a vertical surface, it is necessary to reduce the value by 15%. If the overhanging surface is welded, then by 20%.
In everyday life, inverters are very often used, the current value of which can be changed in the range of 0-200 A. This is quite enough for work on the house. A very useful quality of inverters is the possibility of direct and reverse current welding. When welding electrons go from minus to plus. Moreover, plus more heated. It is good if you need to weld surfaces with different thicknesses to each other.
Therefore, the positive contact is connected to the metal, and the negative contact to the handle with the electrode. When working with thin sheet steel, it is best to use reverse polarity. So you get the maximum heating of the electrode, but you will not do it in the metal.