Patent ID: 6031203
Filing Date: 2000-02-29
Classification: B23K

Abstract:
A method for determining a stability of arc welding between a base metal and a welding electrode, with a welding voltage applied thereto by a welding power source to supply a welding current, repeating arc and short-circuit between said base metal and said welding electrode, said method comprising the steps of:sampling the welding current for the arc period and the welding current for the short-circuit period fed from said welding power source into said base metal and said welding electrode, every cycle of the repetition of arc and short-circuit, in accordance with a predetermined frequency;integrating the welding current for the arc period, and calculating a standard deviation of the integrated welding current for the arc period;integrating the welding current for the short-circuit period, and calculating a standard deviation of the integrated welding current for the short-circuit period;multiplying the standard deviation of the welding current for the arc period by the standard deviation of the welding current for the short-circuit period to produce a first product;sampling the welding voltage for the arc period and the welding voltage for the short-circuit period applied by said welding power source to said base metal and said welding electrode, every cycle of the repetition of arc and short-circuit, in accordance with a predetermined frequency;integrating the welding voltage for the arc period, and calculating a standard deviation of the integrated welding voltage for the arc period;integrating the welding voltage for the short-circuit period, and calculating a standard deviation of the integrated welding voltage for the short-circuit period;multiplying the standard deviation of the welding voltage for the arc period by the standard deviation of the welding voltage for the short-circuit period to produce a second product;calculating a welding stability parameter on the basis of at least one of said first product and said second product;comparing the welding stability parameter with a predetermined reference value; anddetermining the welding stability between said base metal and said welding electrode in response to the result of comparison.