Study on automatic removal of spatter from an arc welding torch nozzle

Abstract

Summary A method to automatically remove the spatter which sticks to the torch nozzle during GMA welding using magnetic electrode wire without touching it has been developed. By selecting a suction method with magnetic force which does not require maintenance work on both the torch and the removal equipment used in various non-touching methods, the countermeasures for decreasing the sticking force of spatter, the removal mechanism and a suitable removing force for it have been examined. With a carbon nozzle, the sticking force of spatter is less and is stable for a long time. With a silicon nitride nozzle, the sticking force of spatter is unstable even at the initial stage and there are some cases where it increases to about ten times that of the carbon nozzle. With a copper nozzle, the sticking force of spatter is less at the initial stage, but after use for a long time, it becomes impossible to remove because it has fused with the nozzle and stuck firmly. The impulse and peak value of the suction force which are necessary for success in removing the spatter when using the carbon nozzle becomes higher accordingly as the increasing speed of the current is lowered. Both the condenser power source and the air-core coil are used as the equipment providing the suction force, and their effectiveness has been confirmed.