A method for determining an interfering coupling between welding circuits (2-i) of a welding system (1) comprises the following steps: applying (S1) a predetermined current profile (SP) in a first welding circuit (2-1) of the welding system (1); detecting (S2) a voltage progression and/or current progression thus induced in a second welding circuit (2-2) of the welding system (1), and determining (S3) the interfering coupling on the basis of the current profile (SP) of the current applied in the first welding circuit (2-1) and of the voltage progression and/or current progression detected in the second welding circuit (2-2).

Two welding wires whose current values are individually variable are placed along a groove of steel plates, and two operations are repeated, the first operation including: passing substantially the same current through both welding wires; generating a cathode spot in front of a molten pool by one welding wire's arc on a welding-direction forward side; and cleaning the steel plates' surfaces by the arc, and the second operation including: passing a pulse current having a higher value than that of the welding wire through the other welding wire, so that a cathode spot is generated in the molten pool by each welding wire's arc to newly form a molten pool; and advancing both welding wires in the welding direction to move the cathode spot to the newly-formed molten pool, and at the same time performing welding within an area where oxides on the steel plates' surfaces are removed.

The invention relates to a pair of two nozzle assembly receptacles (14, 15) for a dual-wire welding torch (1) for two melting welding wires (2, 3), having a torch body (4), a connection (5) for a hose package (6), and having a common gas nozzle (11) and to a dual-wire welding torch (1) with a pair of two nozzle assembly receptacles (14, 15) are constructed as inserts for accommodating and fastening in interfaces (12, 13) in the torch body (4) provided therefor, and the nozzle assembly receptacles (14, 15) respectively have an opening (16, 17) for the accommodation of a nozzle assembly (7, 8) in each case, which openings (16, 17) are arranged at an angle (α) between 0° and 20° to one another, so that the central axes (a, b) of the contact tubes (9, 10) or the welding wires (2, 3) running therein enclose this angle (α) to one another.

A pair of two nozzle assembly receptacles for a dual-wire welding torch for two melting welding wires, has a torch body, a connection for a hose package, and a common gas nozzle, and a dual-wire welding torch has a pair of two nozzle assembly receptacles constructed as inserts for accommodating and fastening in interfaces in the torch body provided therefor, and the nozzle assembly receptacles respectively have an opening for the accommodation of a nozzle assembly in each case, which openings are arranged at an angle between 0° and 20° to one another, so that the central axes of the contact tubes or the welding wires running therein enclose this angle to one another.

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 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 system and method of welding or additive manufacturing is provided where at least two welding electrodes are provided to and passed through a two separate orifices on a single contact tip and a welding waveform is provided to the electrodes through the contact tip to weld simultaneously with both electrodes, where a bridge droplet is formed between the electrodes and then transferred to the puddle.

A welding device has a central unit and a welding torch unit, which can be connected to the central unit. The central unit includes at least one welding current source for providing electric current needed to operate the welding torch unit and includes a control unit. The welding torch unit includes at least a first welding torch with a first welding wire and a second welding torch with a second welding wire. The control unit is configured to carry out a starting process in such a way that firstly a first arc ignition takes place at one of the two welding torches and after a waiting time since the first arc ignition has passed, a second arc ignition takes place at the other of the two welding torches, which until then was not ignited.

The present application relates to an arc welding arrangement and an electric arc welding method to be used with the arc welding arrangement. The arc welding arrangement comprising a first power source, a first electrode connected to say first power source, and a second electrode, said first electrode being adapted to generate a weld pool via a first electric arc present within a first arc region. The second electrode is operated at welding parameters adapted to ensure that excess energy from at least said first electrode is required to maintain said second arc ignited. The method comprises the step of feeding said second electrode so that it is allowed to consume excess energy from said first electrode to maintain said second arc ignited.

A solid-bowl centrifuge screw with a screw flight is provided. The screw flight has at least a first welding layer on a base body of the solid-bowl centrifuge and at least a second welding layer on the first welding layer. Thus, plural welding layers are disposed successively on one another and are applied by shaping build-up welding.