Patent ID: 7335853
Filing Date: 2008-02-26
Classification: B23K

Abstract:
1. A method for the orbital welding of tubular elements held in abutment comprising the steps of: a) striking an arc at a strike point with an orbital welder between an electrode and a seam formed by a first tubular element and a second tubular element held in abutment within a fixture, said first tubular element having a wall, said second tubular element having a wall; b) initiating an orbit of said electrode around an abutment of said first tubular element and said second tubular element; c) adjusting the current of said arc in a pulsed manner from a maximum current to a minimum current at a set frequency; d) decreasing said maximum current in a generally continuous manner as said orbit of said electrode progresses from said strike point, the rate of decrease of said maximum current having a generally inverse relationship to the rate of increase in temperature experienced by said tubular elements; wherein an average current is generally decreasing continuously over time; and wherein said minimum current is held generally constant; and wherein an average temperature of said tubular elements is maintained within a predetermined range; and wherein a resulting weld bead is fully penetrated through said walls of said first tubular element and said second tubular element.