In the situation, when it is necessary to connect metal parts, most often resort to the method of creating a weld, as it is able to provide a fairly high reliability. This method has become widespread not only in industry, but also in ordinary daily life.
The vast majority of home builders periodically use welding. Lucky for those of them, who has welding skills. If they do not exist, then in this case nothing remains, how to turn to specialists.
But if everyone wants to learn how to cook. And the first, what you should pay attention to at the beginning - to get acquainted with the basics of electric welding for beginners. It's about lessons, which tell about features of creation of various seams. It is necessary to start performance of more difficult works only after that, as the owner will gain sufficient experience. Next we will dwell in more detail on the nuances of welding and certain tricks of this process.
Where to start the preparatory stage?
First, what to do, who wants to learn to cook - buy the necessary equipment. Complete set, which will be required to perform such work, will include:
- welding machine;
- set of electrodes;
- slag hammer;
- brush.
When choosing an electrode, you must pay attention to its diameter, which will be determined by the thickness of the welded metal sheet. You should also take care of protection. We will need it for welding:
- welding mask with a special light filter;
- tight clothes with long sleeves;
- gloves, preferably suede.
Mandatory tools for welding must include a welding rectifier, transformer or inverter. It is with the help of these devices and will solve the problem of converting alternating current into direct current, that will allow to carry out welding.
Welding process technology
Starting electric welding, keep that in mind, that this work is carried out in conditions of high temperatures. The electric arc provides performance of similar works, which must be maintained between the electrode and the welded product.
It is during its contact with the workpiece that the base metal and the welding electrode melt. At this point, the phenomenon occurs, which among experts is called a welding bath. In it, the base and the electrode metal are mixed into a homogeneous mass.
The bath can be of different sizes, determined by the welding mode used, spatial position, the speed of movement of the arc, shapes and sizes of the edge, etc. Usually it reaches a width of about 8-15 mm, in length 10-30 mm, and in depth - about 6 mm.
Each electrode has a special coating, called smear. At the time of its melting there is a special gas zone in the arc and above the bath. Thanks to it, the air bond is lost and the interaction of molten metal with oxygen is eliminated. It also contains base and electrode metal vapors.
An alloy appears at the seam, which will allow the melt to come into contact with air, which would worsen the quality of welding. As the electric arc is removed, metals crystallize, as a result there is a seam, thanks to which the parts are firmly connected, welded. There is a protective layer of slag on the seam itself, which must be removed after welding.
These welding
To get the best results when creating a weld, novice welders first need to learn the lessons, where attention is paid to the proper implementation of this work in the early stages. It is desirable to get the practice of welding under the guidance of an experienced specialist, which will not only point out mistakes, but also prompts, how to prevent them in the future. Before you start welding parts, you need to make sure, that it is fairly securely fixed.
It is equally important to ensure compliance with fire safety rules: it is not superfluous to place a bucket of water nearby. This also prohibits the use of wood-based welding. Attention should also be paid to small residues of used electrodes, which should not be left in the workplace after work. Without this, it is impossible to learn to cook metal properly.
Make sure you make sure, that the "ground clamp" is securely fixed. You need to make sure, that the cable was insulated and precisely inserted into a special holder. Before operating the welding inverter, select the calculated current rating, in determining which should be based on the diameter of the electrode. You can then light the arc. This is done as follows: you need to place the electrode at an angle of about 60 degrees relative to the product. Next, you need to slowly spend them on the surface. At this point, sparks appear, now the electrode must touch the metal, and then pick it up, but not higher 5 mm.
If all the recommendations are followed strictly, the arc should ignite. Until the welding is completed, you need to keep the electrode at a distance 5 mm. It should be borne in mind, that during metal welding the electrode rod will gradually burn out.
Therefore, at regular intervals you need to reduce the distance between it and the metal. Approach the electrode to the workpiece slowly. This situation may occur, that it will stick. In this case, you need to turn it slightly to the side. If all attempts do not allow to ignite the arc, then you can try to increase the current.
When the arc lights up, and its flame will become stable, it is possible to begin already to be engaged in surfacing of the platen. The electrode with the ignited other needs to be moved slowly and smoothly horizontally, performing weak oscillating movements. This will lead to that, that the liquid metal will begin to move directly to the center of the arc. If you follow all the recommendations, you can make a reliable seam, formed in the form of small waves, which were created using weld metal.
This situation may occur, that during welding of products the electrode will be completely spent, but it was not enough to create the whole seam. In this case, you need to take a break from work. Turning off the device, you need to insert a new electrode, remove slag from the surface of the seam, and then continue welding. From the recess created at the end of the seam, often referred to as a crater, need to indent about 12 mm and ignite the arc. The electrode should be approached with that calculation, that at contact there was an alloy from metal of the old and again established electrode. Then the welding is performed in the normal mode.
Features of inverter pipeline welding
The method of electric arc welding is suitable for creating a vertical seam provided, that it is located at the end of the pipe. In the case of creating a horizontal seam, the latter must be on its circumference. If you have to perform ceiling and bottom seams, then they must be above and below. Of all these, the latter creates fewer performance problems.
If you have to deal with steel pipes, then the most commonly used method of butt welding, which involves boiling each edge along the height of the walls. To minimize inflows inside the pipe, the electrode should be placed at an angle of no more 45 degrees relative to the horizontal. Such a seam should reach a height 2-3 mm, but wide 6-8 mm. If the products overlap, then in this case the seam will have a height 3 mm, but the width 6-8 mm.
preparation
Before you start electric welding of metal products, preparatory measures need to be taken:
- From the welded alimony it is necessary to remove the top layer.
- If there are irregularities at the ends of the pipe, they should be cut or corrected.
- Next, we begin to process the edges. No less is needed here 10 millimeters of surface, adjacent to the edges of the pipe outside and inside stylishly count to the appearance of metallic luster.
The main stages
Then you can start welding the pipe directly. Each joint must be treated continuously, until they are fully welded. To create rotary and non-rotary joints of pipes with walls no more 6 mm should be in at least two layers. If the walls are wide 6-12 mm, then three layers must be created, more 19 mm - 4 layers. One important nuance must be taken into account when welding pipes: from the next seam, created at the joint, it is necessary to remove slag, only then can you move on to creating a new one.
Particular attention should be paid to creating the first seam, because a lot depends on him. It should be performed as follows, to melt each edge and areas of blunting. It is very important to examine it very carefully, as it may have cracks. If they are found, they must be smelted or cut down, then the area is brewed again. When creating other layers it is necessary to turn the pipe slowly. You need to remember, that the beginning and end of each layer should be offset from the last layer at a distance 15-30 mm.
It is necessary to create a finishing layer with that calculation, that it provided smooth transition to the base metal and at the same time had a smooth surface. It is possible to achieve the highest quality of welding of pipes by means of welding, if the next layer will be executed in the opposite direction in relation to the previous one, while their locking points must be scattered from each other.
conclusion
Welding works are quite complex, therefore, novice welders have to spend a lot of time and effort, to create quality and strong welded joints. But first they need to get an idea of the highlights of the lessons, without which it is impossible to perform high-quality and correct cooking of metal.
It is important not only to prepare all the necessary tools and materials, but also with special care to approach the study of welding technology. This is very important because, that any error may subsequently affect the quality of the weld, and if this is not paid attention to at the initial stage, then in the future all efforts will be in vain, as a result, everything will have to be reworked.