Flux-cored welding wire is a metal sheath, which is made of steel tape with a thickness of 0.2 to 0.5 millimeters. The shell is filled with slag and gas-forming components.
Flux-cored wire is used in shielding gases or for mechanized arc welding with an open arc. Retaining the technological advantages of standard wire, it creates slag and gas protection from atmospheric air. This is especially important when working in open areas. Cored wire provides refining and alloying of the seam. When using it, it is allowed to use a current having a density of 150-170 A / mm2. For manual arc welding with open electrodes, the current density is not more than 20 A/mm2. Cored wire, thus, allows to increase the efficiency of the process by one and a half to two times.
There are different brands of continuous electrodes. So, for example, for cold welding of cast iron, material grade PP-Ch1 is used, for hot welding - PP-Ch3.
It should be noted that the technological process of joining metal using electrodes is one of the main methodssolving various problems of scientific and technological progress. This process is used in almost all areas of the national economy. Cored wire is considered a very promising material. Its use increases not only productivity, but also the quality of work carried out.
It is used to expand the range of deposited steels. Its use is necessary especially in cases where alloyed monolithic wire for certain types of steel cannot be obtained by a metallurgical method.
Cored wire is classified according to the protection method used, the main purpose, core type, mechanical properties, and the ability to weld in various positions.
Most of today's products are used for welding low alloy and low carbon structural steels. Cored wire is produced for special and general purposes. The first category includes the material used in work with the forced formation of a seam.
Of particular importance is the classification of the material according to the properties of the seam and welding joint. This indicator allows you to determine the suitability of products of a particular brand for welding on a given design, if the minimum requirements for the mechanical properties of materials have already been determined for it. Verification of compliance with the requirements is carried out by identifying the minimum required indicators of temporary resistance to rupture, as well as the impact strength of the suture metal. The evaluation is given when testing standard samples. To determine the type of wire according to the guaranteed temporary resistance to rupture, the tensile strength is set. When classifying flux-cored wire, it is customary to indicate the type of product, the strength of the material and the permissible positions (spatial) of welding.
