Electrodes

Manual arc welding is used to solve domestic and professional problems. Moreover, the result of its application depends not only on the skill of the welder, but also on consumables. Currently, there are dozens of manufacturers that produce various brands of electrodes. According to a number of signs, they can be divided into several types.

The electrode is a metal core coated with a special compound called “coating”. In the process, the core melts and forms a seam together with the metal of the product. The coating burns out at the same time with the formation of gas, which is necessary to protect the welding zone from the harmful effects of air (we are talking primarily about the negative effect of oxygen and nitrogen on the molten metal).

To obtain high-quality welds, the chemical composition of the electrode core should be similar to the chemical composition of the metal being welded. On this basis, consumables are distinguished for welding carbon, alloy, high alloy, stainless and heat-resistant steels, as well as aluminum and cast iron. For household needs, carbon and low alloy steel electrodes are most often used.

Types of electrodes by appointment:

• for welding carbon and low alloy structural steels with temporary tensile strength up to 60 kgf/mm² (600 MPa). Indicated by the letter U (GOST 9467-75);
• for welding alloy structural steels with a temporary tensile strength of more than 60 kgf/mm² (600 MPa). Indicated by the letter L (GOST 9467-75);
• for welding alloyed heat-resistant steels. Indicated by the letter T (GOST 9467-75);
• for welding high alloy steels with special properties. Indicated by the letter B (GOST 10052-75);
• for surfacing of surface layers with special properties. Indicated by the letter H (GOST 10051-75).

Coating the welding electrodes is able to absorb moisture from the air. In this case, the wet coating burns unevenly and does not melt well. As a result, it is difficult to carry out welding work, and the resulting seams may have defects in the form of cracks or pores. To remove excess moisture from the electrodes, they are calcined at a certain temperature (it is indicated in the documents for the electrodes or on the packaging).