This series of welding wire is based on the actual needs of our country pipeline construction and market present situation, the innovation of the high toughness self-protection flux cored wire series, do not need gas shielded welding process, especially suitable for field construction. This series of welding wire to fill the domestic blank, broke the monopoly of the foreign product technology, as the only winners in the domestic like product successfully applied in national key project "the second line of west-east gas". This series of wire has been applied to metallurgical blast furnace installation, outdoor large steel structure manufacture, high-rise steel structure building, offshore oil platform construction, etc.