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`This application is a divisional of U.S. Patent Application 13/003,673,
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`filed
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`January 11, 2011, which is a U.S. National Phase Application of PCT International
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`Application PCT/JP2010/000927, which is incorporated herein by reference.
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`TECHNICAL FIELD
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`The present invention relates to a welding method and a welding system which
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`uses a plurality of welding robot systems, and performs simultaneous welding on one
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`welding line using welding electrodes mounted on the welding robot systems.
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`BACKGROUND ART
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`Conventionally,
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`in a welding method at production sites, welding robots have
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`been introduced to advance automation and labor saving. Moreover,
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`in recent years,
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`so—called high-deposition welding with a large amount of a consumable welding electrode
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`(that is, a welding wire) which melts and transfers to a base material tends to be
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`performed in order to achieve high efficiency in the welding method.
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`"Tandem welding"
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`of aligning two electrodes on a welding line and performing one-pool two—arc welding is
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`often adopted, as a welding method for performing high-deposition welding while
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`maintaining high welding quality.
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`A two—electrode integrated torch, or two single-electrode torches which are
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`fixedly arranged in proximity to each other are generically referred to as a "tandem
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`welding—dedicated torch" for convenience of the following description. Tandem welding
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`is applied to a welding process for actual production by a welding system which has a
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`tandem welding—dedicated torch mounted on a welding robot, and is constituted by
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`required apparatuses (for example, refer to PTL 1).
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