A flux-cored wire according to an aspect of the present invention includes: a steel sheath; and a flux filling the inside of the steel sheath, in which the flux contains 0.11% or more in total of a fluoride in terms of F-equivalent value, 4.30% to 7.50% of a Ti oxide in terms of TiO.sub.2 equivalent, 0.30% to 2.40% in total of an oxide in terms of mass %, and 0% to 0.60% in total of a carbonate in terms of mass %, the amount of a Ca oxide in terms of CaO is less than 0.20% in terms of mass %, the amount of CaF.sub.2 is less than 0.50%, a chemical composition of the flux-cored wire is within a predetermined range, a Z value is 2.00% or less, a V value is 5.0 to 27.0, and Ceq is 0.30% to 1.00% or less.

A method and apparatus for depositing metals and metal-like substances in two and three dimensional form without a substrate in a safe, rapid and economical fashion using gas shielded arc welding equipment and programmable robotic motion. The method and apparatus includes the use and application of robotic controls, temperature and position feedback, single and multiple material feeds, and semi liquid deposition thereby creating near net shape parts particularly well suited to rapid prototyping and lower volume production.

A method for producing an additively manufactured object includes melting and solidifying a filler metal by use of an arc, and depositing and forming a plurality of layers of molten beads to produce a built-up object, and the method includes: shaping the molten bead of a previous layer; and monitoring a temperature of the molten bead of the previous layer. Shaping of the molten bead of a next layer is started when the temperature of the molten bead of the previous layer is equal to or lower than an allowable interpass temperature.

A system for melting metals for casting includes one or more arc welding power supplies configured to provide one or more arc welding outputs, and one or more electrodes operatively connected to the one or more arc welding outputs. A solid metal holder is configured to hold a solid metal to be melted by one or more arcs formed between the one or more electrodes and the solid metal to generate a molten metal. A container is positioned proximate the solid metal holder to receive the molten metal. A robot is proximate both the container and a mold and/or a die cast machine. The robot has an arm configured to manipulate the container containing the molten metal and pour the molten metal from the container into the mold and/or the die cast machine for casting.

A gas shielded triple-wire indirect arc welding device has three welding wires and the two arc power supplies. In a gas shielded triple-wire indirect arc welding method, before welding, one of three welding wires is first connected to positive electrodes of a first arc power supply and a second arc power supply, the other two welding wires are respectively connected to negative electrodes of the first arc power supply and the second arc power supply, and a welding workpiece is not connected to the arc power supplies. The welding wire connected to the positive electrodes of the two arc power supplies are arranged in the middle, and the other two welding wires are respectively arranged on both sides. The welding method is used for implementing build-up welding.

Method for compensating an interfering influence on a welding current, provided by a welding power source (4) for welding a workpiece (3), from another welding power source (4′), comprising the steps of: (a) providing (SA) a compensation voltage (U.sub.Komp), which is calculated on the basis of a welding current progression provided by the other welding power source (4′); (b) subtracting (SB) the compensation voltage (U.sub.Komp) from a measured voltage (U.sub.Mess), measured by a voltage measurement unit (8) of the welding power source (4), so as to determine a corrected measured voltage (U′.sub.Mess); and (c) regulating (SC) the welding current generated by the welding power source (4) as a function of the corrected measured voltage (U′.sub.Mess).

An arc electric welding head comprising a first contact device housing a first duct for feeding a first electrode and providing electrical contact between a first power source and said first electrode, a second contact device housing a second duct for feeding a second electrode and providing electrical contact between a second power source and said second electrode, said first and second contact devices being electrically insulated from each other, said first and second ducts being parallel.

Embodiments of additive manufacturing systems are disclosed. In one embodiment, an additive manufacturing system includes an array of multiple electrodes for sequentially depositing material layer-by-layer to form a three-dimensional (3D) part. The system includes a power source to provide electrical power for establishing a welding arc for each electrode. The system includes a drive roll to drive each electrode. The system also includes a controller to operate the system at a first deposition rate to form first resolution contour portions of a layer of the part. The controller also operates the system at a second deposition rate to form second resolution fill portions of the layer of the part. The system provides variable width deposition at the second deposition rate using a variable number of the electrodes. The first deposition rate is lower than the second deposition rate, and the first resolution is higher than the second resolution.

Systems for multi-wire submerged arc welding including a flux-cored wire electrode comprising an internal flux, the internal flux comprising about 5% to about 70% of a carbonate compound and less than 25% of calcium fluoride (CaF.sub.2) by weight of the flux; an external flux for submerged arc welding, are provided such that, after a submerged arc welding process, the systems provide a weld metal comprising nitrogen in an amount of less than 100 ppm. Methods of performing multi-wire submerged arc welding using a flux-cored electrode and an external flux are also described.

An arc electric welding head comprising a first contact device housing a first duct for feeding a first electrode and providing electrical contact between a first power source and said first electrode, a second contact device housing a second duct for feeding a second electrode and providing electrical contact between a second power source and said second electrode, said first and second contact devices being electrically insulated from each other, said first and second ducts being parallel.