Abstract: The invention relates to a laser cutting method for cutting a stainless steel workpiece using laser beam generation means comprising a silica fibre with an ytterbium-doped core to generate the laser beam. Preferably, the laser beam generated by the ytterbium-based fibre has a wavelength between 1.07 and 1.09 ?m, a quality factor of the laser beam is between 0.33 and 8 mm.mrad, and the laser beam has a power of between 0.1 and 25 kW. The assistance gas for the laser beam is chosen from nitrogen, helium, argon and mixtures thereof, and, optionally, it further contains one or more additional compounds chosen from O2, CO2, H2 and CH4.

Abstract: The invention relates to a laser cutting method for cutting a C—Mn steel workpiece, characterized in that laser beam generation means comprising at least one silica fiber with an ytterbium-doped core is used to generate the laser beam. Preferably, the ytterbium-based fiber has a wavelength between 1.07 and 1.1 ?m, preferably 1.07 ?m, the quality factor of the laser beam is between 0.33 and 8 mm.mrad, and the laser beam has a power of between 0.1 and 25 kW. The assistance gas for the laser beam is chosen from nitrogen, helium, argon, oxygen, CO2 and mixtures thereof, and, optionally, it further contains one or more additional compounds chosen from H2 and CH4.

Abstract: The invention relates to a wire-guide/nozzle assembly (11, 13) for an electric arc welding torch, comprising at least one nozzle (11) for delivering gas and at least one wire-guide system (13) for guiding at least one consumable wire, characterized in that the downstream end (20) of the wire-guide system (13) runs into the nozzle (11). The peripheral wall of the nozzle (11) has at least one cut-out (10) through which the wire-guide system (13) passes. The wire-guide system (13) is fastened to the nozzle (11). The TIG welding torch comprises a wire-guide/nozzle assembly (11, 13).

Abstract: The invention relates to a wire-guide/nozzle assembly (11, 13) for an electric arc welding torch, comprising at least one nozzle (11) for delivering gas and at least one wire-guide system (13) for guiding at least one consumable wire, characterized in that the downstream end (20) of the wire-guide system (13) runs into the nozzle (11). The peripheral wall of the nozzle (11) has at least one cut-out (10) through which the wire-guide system (13) passes. The wire-guide system (13) is fastened to the nozzle (11). The TIG welding torch comprises a wire-guide/nozzle assembly (11, 13).

Abstract: The invention relates to a wire-guide/nozzle assembly (11, 13) for an electric arc welding torch, comprising at least one nozzle (11) for delivering gas and at least one wire-guide system (13) for guiding at least one consumable wire, characterized in that the downstream end (20) of the wire-guide system (13) runs into the nozzle (11). The peripheral wall of the nozzle (11) has at least one cut-out (10) through which the wire-guide system (13) passes. The wire-guide system (13) is fastened to the nozzle (11). The TIG welding torch comprises a wire-guide/nozzle assembly (11, 13).

Abstract: Methods for hybrid laser/MIG welding processes. A bevel formed between the edges of material to be welded together is partially filled with molten metal. The molten metal is delivered in the form of a filler wire, which is melted by a combined electric arc and laser beam. The welding speed is at least 2 m/min, the filler wire feed speed is at least 20 m/min and the filler wire diameter is less than 1.2 mm.

Abstract: A method and an apparatus for a hybrid laser beam and electric arc welding process. A laser beam, an electric arc, a shielding gas and a consumable welding wire are used to create a weld on a steel work piece by melting the welding wire. The weld contains 30 to 1000 ppm titanium by weight, at least 0.7% manganese by weight, 50 to 1000 ppm oxygen by weight, and less than 10% nickel. The welding wire is either solid welding wire or cored welding wire, and may contain, in varying percentages: titanium, manganese, iron, nickel, boron, molybdenum, carbon or chromium.

Abstract: The invention relates to a laser cutting method for cutting a C-Mn steel workpiece, characterized in that laser beam generation means comprising at least one silica fiber with an ytterbium-doped core is used to generate the laser beam. Preferably, the ytterbium-based fiber has a wavelength between 1.07 and 1.1 ?m, preferably 1.07 ?m, the quality factor of the laser beam is between 0.33 and 8 mm.mrad, and the laser beam has a power of between 0.1 and 25 kW. The assistance gas for the laser beam is chosen from nitrogen, helium, argon, oxygen, CO2 and mixtures thereof, and, optionally, it further contains one or more additional compounds chosen from H2 and CH4.

Abstract: The invention relates to a laser cutting method for cutting a stainless steel workpiece using laser beam generation means comprising a silica fibre with an ytterbium-doped core to generate the laser beam. Preferably, the laser beam generated by the ytterbium-based fibre has a wavelength between 1.07 and 1.09 ?m, a quality factor of the laser beam is between 0.33 and 8 mm.mrad, and the laser beam has a power of between 0.1 and 25 kW. The assistance gas for the laser beam is chosen from nitrogen, helium, argon and mixtures thereof, and, optionally, it further contains one or more additional compounds chosen from O2, CO2, H2 and CH4.

Abstract: An electric-arc welding process for assembling parts that are components of a motor vehicle, in which a consumable wire is used that is subjected to a cyclic mechanical movement. The wire is moved closer to and then further away from the parts to be welded so as to create a short arc between the end of the consumable wire and at least one of the parts to be joined. In this way, molten metal is deposited in order to progressively produce a welded joint between the parts.

Abstract: A welding machine with a power source and an inverter. The inverter has at least one switching leg, made up of switches in series, and an output terminal. The power source has a circuit for controlling the switches by delivering an on-signal or and off-signal. The power source also has a transformer linked to a rectifier. The power source also has a circuit for detecting the voltage that the terminals of each switch of the inverter. A pilot circuit is also present for receiving control and voltage signals. The pilot circuit then sends a pilot circuit to each of the switches. The pilot signal corresponds to an on-command when the control signal corresponds to an on-signal and when the voltage between the power electrodes is very close to zero.

Abstract: A wire-guide/nozzle assembly for an electric arc welding torch, with at least one nozzle for delivering gas and at least one wire-guide system for guiding at least one consumable wire, distinguished in that the downstream end of the wire-guide system runs into the nozzle. The peripheral wall of the nozzle has at least one cut-out through which the wire-guide system passes. The wire-guide system is fastened to the nozzle. A TIG welding torch utilizing such a wire-guide/nozzle assembly.

Abstract: A method and a system for the plasma arc cutting of a workpiece with automatic adaptation of the characteristics of the plasma jet by making various corrections, simultaneously and in real time, to several parameters, including the cut path.

Abstract: An emissive electrode insert formed from an alloy containing hafnium and zirconium. The insert typically contains at least about 80% hafnium by weight and about 0.1 to about 8% zirconium by weight. The invention also relates to a plasma torch electrode formed from an electrode body with a cavity into which such an emissive insert is fitted, to a plasma torch utilizing such an electrode, and to a plasma cutting process for cutting a steel workpiece, in which such a plasma torch is employed.

Abstract: Process for the arc welding in pulsed mode of one or more workpieces made of carbon steel, stainless steel, aluminum or aluminum alloy, with the use of a gas shield, in which an electric arc welding torch is supplied with at least one consumable wire at a wire feed speed (Vwire) and the consumable wire is subjected to current pulses, in order to melt the end of the consumable wire in which, for a given pulse frequency, a wire feed speed (Fwire), a mean current (Imean) value and an rms current (Irms) value are chosen, so as to detach one drop of molten metal per current pulse and to obtain a low degree of spatter.

Abstract: Protective cap for a plasma arc working torch, includes a cap body (7) having an opening (17) for the passage of plasma gas, the cap body (7) being made of at least one material of ceramic type. The ceramic is a silicon nitride or an aluminum silicate. Preferably, the ceramic cap body (7) is clad with boron nitride deposited on the external surface of the cap body, the thickness of the cladding of boron nitride being less than 3 mm. Torch provided with such a cap and its use in a steel plate plasma cutting operation.

Abstract: A flux-cored wire for welding shielded by a flow of gas, in particular of the rutile or slag-free type, composed of an outer metal sheath and a central core comprising filling elements, and an MAG gas-shielded welding process using such a flux-cored wire for producing a welded joint on a steel construction, such as an offshore platform or a storage tank. The welded joint obtained has improved impact strength and proved toughness, and contains less than 65 ppm nitrogen, from 300 ppm to 0.12% carbon, from 0.01% to 0.6% silicon, from 0.9% to 1.9% manganese, from 20 ppm to 0.08% titanium, from 1 ppm to 80 ppm boron, from 5 ppm to 150 ppm alumin from 10 ppm to 0.02% niobium and from 10 ppm to 0.02% vanadium.

Abstract: An installation and a method for oxygen arc cutting of a metal workpiece containing at least a ferrous material, in particular a structural steel workpiece, which consists in: pre-heating locally a priming zone of the metal workpiece to be cut by subjecting the priming zone to a plasma jet; then in producing a localized fusion and/or combustion of the ferrous material contained in the workpiece, using the plasma jet or a combination of the plasma jet and an oxidizing gas flow to obtain a perforation along the whole thickness of the metal workpiece; once the perforation has been obtained, in synchronously displacing, the plasma jet and the oxidizing gas flow along a cutting path to produce a predefined slit through the metal workpiece.

Abstract: The invention relates to an oxy-fuel torch. The torch comprises a body (10) comprising a number of pipes for conveying at least two streams of gas between inlets (14, 15) and outlets; at least two valves (16, 20, 22) mounted in said body capable of adopting a closed rest position and an open active position; a single control (12) for said valves and mounted so that it can move on the body and able to be moved so that it collaborates with said valves, capable of adopting a first stable position in which all the valves are at rest and at least one second stable position in which at least one of the valves is in the active position; controllable means (40) of locking said control (12) so as to secure it, at rest, to said body; and at least one controllable delivery adjusting means (46, 48) mounted on said body for adjusting the delivery of at least one of said streams of gas.

Abstract: A method and a device for pulsed arc welding in which the electric current has conductance with pulse drops and/or pulse rises between 50 A/ms and 1000 A/ms, and more particularly between 100 A/ms and 500 A/ms, with the exception of a triangular pulse. The invention is applicable to MIG or MAG welding.