The modern process of manufacturing metal products involves the use of the latest technology. This allows products to meet demand requirements. For this, various materials with certain characteristics are used.
An electrode is an element necessary for welding. For each type of metal and its processing techniques, various types are used. Therefore, there are quite a few brands of electrodes.
general characteristics
As already mentioned, an electrode is a material involved in the arc welding process . They began to be used in the 19th century. But today's varieties of them have improved characteristics. They allow you to speed up the manufacturing process and reduce the consumption of materials, energy, etc.
In order for the weld to meet the norms and quality standards, for each type of metal it is necessary to select its own specific type of electrodes. Otherwise, the product will be unusable.
It should also be noted that the electrodes, whose price is much lower than average, are made of low-quality materials. Therefore, to comply with the correct technology, it is necessary to purchase welding elements from trusted manufacturers. Only in this case, there is no doubt that the electrodes will be made in compliance with all requirements.
Device
The metal rod of the electrode is capable of conducting current. Thanks to this design, electricity comes to the work surface, and the master performs arc welding.
Previously, the described elements were used only uncovered. Today, such products are used as a wire for welding in an inert gas environment. A characteristic of the electrodes suggests the presence of a special coating layer on them. It is possible to carry out work with their help in different positions, which reflects the class of the product.
Products manufactured by manufacturers are mostly universal in terms of current flow. It can be constant of direct or reverse polarity, as well as variable. The choice depends on the properties of the metal.
Electrode Classes
The allowable welding positions distinguish 4 classes of electrodes:
- Products that accept all the provisions for creating a seam.
- Electrodes suggesting use in almost all directions except the vertical (from bottom to top).
- Electrodes of the 3rd class are designed for welding from top to bottom, its horizontal and lower versions.
- Products used for the lower direction.
To indicate the purpose of the electrodes, Russian letters are used. But if the product is imported, then the marking will have English designations. Such varieties are more expensive than domestic ones. For example, for high-carbon steel, the designation is letter U. But alloyed heat-resistant steels go on sale with the designation T.
Also, modern electrodes can be non-melting and melting. The last of them, in turn, are divided into 2 varieties - covered or not. Coating plays the role of protection for the welding arc from exposure to the atmosphere.
Electrodes 4 mm in diameter are most often used in arc welding. But on sale are products with a rod from 2.5 to 5.0 mm.
Varieties of application
Existing brands of electrodes allow you to choose their most suitable variety for each type of work. This guarantees high quality processing.
An improperly selected type of electrode causes an unsatisfactory result. There is a list of the main varieties of materials to be welded:
- heat-resistant alloyed steel;
- high alloy steel with special properties;
- structural steel;
- non-ferrous metals;
- cast iron.
Each of them requires its own type of electrodes. Experienced craftsmen know which class of product is more suitable for each process and will not use, for example, for surfacing electrodes used for welding cast iron.
Types of Coatings
The determination of the brand of electrodes is also carried out based on their coverage. They are indicated by letters.
A - have an acid coating (iron oxide, silicon, manganese).
B - the main coating (calcium carbonate, calcium fluoride).
C - electrodes have a cellulose top layer. It can be flour, cellulose or another organic compound.
P - coating is made of rutile. Certain mineral or organic compounds are introduced into the layer of this substance.
P - other, less frequent in use varieties of coating. They are used for special technological operations.
Methods of application of electrodes also depend on the type of coating. Therefore, it is necessary to know their properties.
Description of Coatings
The acidic electrodes of brand A have certain toxic characteristics. Most often, their purchase is carried out in bulk at a price of 1 kg from 70 rubles.
When purchasing the main varieties of class B, it is necessary to remember that they are used for welding critical structures with direct current of variable polarity. Their cost also starts from 70 rubles / kg.
Grade C creates gas protection for the material. These are electrodes, the price of which can reach 200 rubles / kg.
Well proven in the manufacturing process of products of brand P. Additives that are part of the coating, not only provide gas surface protection, but also contribute to low metal spatter. On sale there are similar products worth 700 rubles / kg.
Other varieties can even be sold individually. Their cost varies depending on the type of work.
Subclasses
Electrodes for carbon low alloy steel include 9 types of products. These are MR-3, OZS-6, ANO-3, UONI 13/45, 13/55, etc. Their group is marked U.
For alloy structural steels use 5 varieties of electrodes. Their marking has the letter L.
If it is necessary to work with heat-resistant alloy steel, type T products are purchased. This group includes 9 electrodes.
Group B is for high alloy steel with special characteristics.
When surfacing, use electrodes with the designation N. This allows you to weld layers of materials that have special characteristics.
What type of current to use in the work also depends on the type of product. Many varieties are universal today. But there are narrowly targeted subspecies. The alternating current electrodes are MR-3, ANO, and the constant electrodes are UONI 13/55, 13/45.
Selection tips
An electrode is one of the elements of arc welding, on which the quality of the final product depends. Therefore, it is necessary to approach his choice as responsibly as possible.
In no case should you buy cheap products. Their production is most often performed without compliance with regulatory requirements. In the process, they may lead to marriage or create insufficiently durable seams.
The price range for the products presented is quite large. But it does not make sense to purchase cheaper but inappropriate electrodes for this metal processing process. Their characteristics must fully comply with welding technology for a particular type of work. Savings in this case are simply inappropriate. Knowing the labeling of the electrodes, you can easily choose the right kind of product.
Having become acquainted with the equipment for welding, we can conclude that the electrode is an indispensable element of the process. The result of the work depends on its type and quality.