In industry and construction, welding of metal products is often used. Sometimes you can not do without it. The process is complex and time-consuming. In some cases, welding of fillet welds should be used as the joint. This type of connection is considered one of the most reliable and durable. However, it is impossible to perform angle welding without special knowledge, because in the process of work it is necessary to take into account many small nuances.
Welding Features
The corner seam is quite common. With it, you can connect two metal plates or profile pipes. The main thing is that the distance between these two products should be no more than 180 degrees.
In some cases, it is necessary to connect several products into one large metal structure, where the joints will have an angle of 90 degrees. All this is necessary so that the design is reliable, durable and can withstand heavy loads.
Corner seams are quite common, especially when you need to produce a large and durable structure. They usually have corners that need to be carefully worked and joined. Many other methods can be used for this, but welding is the most reliable way to join two steel products.
Special requirements are imposed on this type of work, since the strength of the entire structure depends on the quality of the seam. This type of connection is considered one-piece. It can be carried out using gas equipment, or other, more modern installations. The most important thing is to strictly comply with the technology.
Types of seams
The corner seam is divided into the following types:
- overlapped;
- when at the junction the edges of the products are tightly adjacent to each other;
- one edge of the product is applied to the flat surface of the other (T-joint);
- without groove and with hem.
Unlike conventional welding, making neat and durable fillet welds is much more difficult. The work is complicated by the fact that welding must be carried out in different positions. Even a professional welder can have problems in work, for example, if you need to make a T-joint between products that are also turned upside down. In addition, the corner seam may be intermittent or continuous, short or long. A short seam does not exceed 2.5 centimeters, and a long one - 10 centimeters.
Difficulties during welding
In order for the master to be able to carry out the most even and high-quality seam, it is necessary to know about the main defects that may occur during the seam. Most often, the fillet weld is unreliable due to the fact that the deposited material lies unevenly. Under the influence of high temperature, the metal melts and rushes down. As a result, the upper edge cannot normally join the joint. Sooner or later, under the influence of a heavy load, the structure will disintegrate.
Main problems
An incorrect angle can also ruin a vertical fillet. Two products that need to be joined in such a seam are rarely arbitrary shapes. In this matter, it is very important to correctly calculate the fillet weld. Products must be in the correct shape. Usually they have the same parameters (length, width and thickness).
In order to carry out the work qualitatively, it is necessary to carefully approach the choice of voltage parameter. If the current is too weak, this will cause the leg to be convex. This means that the base material will not melt well. Conversely, if the current is too intense, the leg will become concave. The sides of the metal product will have too deep penetration. As a result, the design will still be of poor quality.
Preparation for work
To carry out work as efficiently as possible, it is not enough to have good equipment, to know about possible defects and to observe safety rules. Before the master begins to work, he must properly prepare the sides of the weld.
Basic Rules
If it is necessary to connect plates to each other whose thickness does not exceed 5 mm, then special preparatory measures are not required. If rust is present on the material, it must be removed with a special brush.
Only after this can you markup, fix the products well and start welding. In the same way they act if it is necessary to conduct a weld of an angular joint with an overlap. So that in the end the structure was strong enough, it is necessary to put two seams on each side.
The work is complicated if you need to work with steel, the thickness of which exceeds 5 mm. In this case, the master must perform a slight bevel at 45 degrees on the mounting plate. This will form a small place where molten metal will flow. As a result, the corner seam will be more durable and reliable. When the master works with steel with a thickness of more than 1 cm, he needs to cut edges on both sides. This technology helps protect the seam from burning.
After the edges are prepared, and the parts are firmly installed in place, the specialist should not forget about the installation of tacks on both sides. This is necessary so that during the welding the seam does not warp, and the metal product does not deform.
In order to make the construction as durable and accurate as possible, welding is carried out not simultaneously from two sides, but alternately. It is important to completely finish work on one side, and then switch to the other. If this rule is not followed, tack can not withstand the load and most likely burst.
Angle Welding Methods
During this operation, the likelihood of defects is very high. Professional workers use several basic techniques, thanks to which you can get the most durable and accurate seam. To understand how to cook the fillet weld correctly and what technique to use, you need to pay attention to the general situation and choose the most convenient welding option.
The boat method
This method is suitable for welding if the master works with small structures that are on a solid surface, but not fixed on it. They can be turned over. This technique is mainly used by novice specialists. In this case, the product is installed in the form of the letter V. The design is somewhat reminiscent of a boat, from this came the name of the technique.
The master should hold the electrode vertically, tilting it slightly towards himself. In this case, during operation it is impossible to make oscillatory movements. The duration of the work depends on the thickness of the metal. Sometimes it takes several approaches to make a really strong and even seam.
To give the seam the necessary width, the master can later perform transverse welding. Thanks to this method, the specialist is able to apply filler material simultaneously on two sides. This helps to avoid the occurrence of defects, low-quality joints.
Lower position
The specialist will not be able to fold large structures in the shape of a boat, so welding should be done in the lower position. The master should tilt the electrode slightly and operate at an angle of 45 degrees. In this case, you need to move it left and right. This is necessary in order to completely fill the seam.
When the master just starts welding, there is no need to make lateral movements. At the first stage, it is important to qualitatively connect the metal elements. Experts recommend making small jerks during work. This is necessary in order to slightly drive off the slag flowing down to the seam. If the master does not do this, then the slag can completely block the visibility of the working surface. If the main seam is made correctly, firmly and without defects, then the following seams can be applied.
Even if the master’s work was carried out efficiently, sometimes the weld, which was performed at an angle, can have a sloppy and unattractive appearance. This is due to the fact that the joints are often uneven. They are slightly convex above the main surface. In addition, slag residues, small scale and metal particles may be present on the seam.
Features of stripping
In order for the finished product to have an attractive appearance, you need to get rid of all this. This process is called stripping. The specialist must act in several stages. First, with the help of a skein or chisel, he knocks scales, and then with a grinder he evens the surface of the seam. If the master still cannot make the seam even, this can be corrected by applying molten tin to the surface.