TWIN-TORCH TYPE PLASMA SPRAYING METHOD AND APPARATUS

摘要

PURPOSE:To attain reduction in noise and to save the consumption amount of gas, by forming an arc for generating plasma by using two arc torches and protecting the anode final point of an arc by inert gas and separating plasma immediately before a matrix. CONSTITUTION:Inert gas such as argon is flowed as plasma gas as shown by arrows 34, 40 to start a main torch 29 and a sub-torch 30 and a hairpin arc 45 fixed at the start and final points thereof is generated between electrodes 31, 37 of which the leading ends are respectively protected by inert gas and the plasma gas is heated by said arc to generate plasma. The film material 48 sent in from a material feed-in pipe 47 is immediately heated to high temp. by low-noise laminar plasma 46 and melted to advance while accompanying a plasma flame 54. The plasma is separated immediately before a matrix 56 by a plasma separation means 28 and only a molten film material is collided with the matrix 56.