| 2004 №07 (04) | 2004 №07 (06) |
The Paton Welding Journal, 2004, #7, 21-25 pages
Estimation of forces affecting the spray metal in electric arc metallising
Yu.S. Korobov
The Urals State Technical University, Ekaterinburg, Russian FederationAbstract
Causes of difficulties underlying formation of a concentrated flow of spray material in electric arc metallising are considered. It is assumed that detachment of a large-diameter drop from the electrode tip under the effect of gas-dynamic pressure and its tear into smaller droplets under the impact of electromagnetic and gas-dynamic forces occur simultaneously in the arc. As shown by the estimations performed, forces of an electromagnetic nature have a magnitude similar to that of the aerodynamic ones. However, they differ in direction. Their level and direction satisfactorily explain the possibility of formation of fine droplets. In addition, the calculation data show that designing of a nozzle assembly of the electric arc metallising unit requires that special measures be taken to prevent scatter of droplets from the jet axis.
Keywords: electric arc metallising, spray material, finely dispersed components, gas-dynamic pressure, electromagnetic forces
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