Open AccessWelding Current Distribution in the Work-piece and Pool in Arc Welding
Author(s) -
Alexander Rybachuk,
Tsejen Gu
Publication year - 2015
Publication title -
nauka i obrazovanie
Language(s) - English
Resource type - Journals
ISSN - 1994-0408
DOI - 10.7463/0615.0782051
Subject(s) - welding , current (fluid) , work (physics) , arc welding , arc (geometry) , distribution (mathematics) , mechanical engineering , materials science , metallurgy , engineering , electrical engineering , mathematics , mathematical analysis
In order to select the optimal configuration of controlling magnetic fields and build rational construction of magnetic systems, we need to know the distribution of welding current in the molten metal of the weld pool. So the objective of the work is to establish the calculated methods for determining current density in the weld pool during arc welding. The distribution of welding current in the pool depends on the field of the electrical resistance, which is determined by the deformed temperature field while arc moves with the welding speed. The previous works have shown experimentally and by simulation on the conductive paper that deformation of temperature field defines deformation of electric field. On the basis thereof, under certain boundary conditions the problem has been solved to give a general solution of differential equation, which relates the potential distribution to the temperature in the product during arc welding. This solution is obtained under the following boundary conditions: 1) metal is homogeneous; 2) input and output surfaces of heat flux and electric current coincide; 3) input and output surfaces of heat flux and electric current are insulated and equipotential; 4) other (lateral) surfaces are adiabatic boundaries. Therefore, this paper pays basic attention to obtaining the analytical solution of a general differential equation, which relates distribution of potential to the temperature in the product. It considers the temperature field of the heat source, which moves at a welding speed with normal-circular distribution of the heat flow at a certain concentration factor. The distribution of current density is calculated on the assumption that the welding current is introduced through the same surface as the heat flux and the distribution of current density corresponds to the normally circular at a certain concentration factor. As a result, we get an expression that allows us to calculate the current density from the known distribution of heat flux density in the product. Using the results we can define the desired configuration of magnetic fields to create the necessary electromagnetic forces in the weld pool