The invention relates to an orbital welding device for mobile use in order to join a first pipe end (1) and a second pipe end (2) along a circumferential joint (3) by means of at least one weld seam (4), particularly for producing a pipeline (5) to be placed on land. The inventive device comprises a guide ring (6), which can be oriented toward the first pipe end (1) and the circumferential joint (3), and an orbital carriage (7) that can be motor-displaced along the guide ring (6) via an advancing device (8). On the orbital carriage (7), a laser welding head (12) for directing a laser beam (10) into a laser welding zone (13) is mounted in a manner that enables it to be oriented toward the circumferential joint (3) whereby enabling the production of the weld seam (4) along the circumferential joint (3) by displacing the orbital carriage (7). The laser beam (10) is produced by a high-power fiber laser beam source (9) located, in particular, on a mobile transport vehicle (35) while being situated at a distance from the orbital carriage (7), is guided by light guide (11) passing though a tube bundle (50) to the orbital carriage (7) and then supplied to the welding head (12). A significant advantage of the invention resides in the fact that the joining of two pipe ends by means of only one single welding process during a short period of time is made possible in the field with autonomous operation.

Orbital welding device for pipeline construction

Methods and systems are provided for dual fillet or T-joint welding, in which two electrodes are directed to opposite sides of a joint between two workpieces and the electrodes are energized with DC pulse or AC welding waveforms at a controlled waveform phase angle. The systems include a synchronizing controller to synchronize the welding waveforms, and a workpoint allocation system provides one or more workpoint values to the welding machines to provide synergic control of the dual fillet welding according to a user selected system workpoint value or parameter. The systems and methods further provide for synchronized workpoint value modulation for the opposite sides of the dual fillet weld.

Dual fillet welding methods and systems

The invention relates to a welding unit (27), comprising a welding device (1), with a welding torch unit (29) which may be connected thereto by means of a tube group (23, 28). At least one controller (4), a welding power supply (2) and, optionally, a wire supply unit (30) are arranged in the welding device (1). The welding torch unit (29) comprises at least two separate welding burners (10, 35), embodied for carrying out at least two independent separate welding processes. The invention further relates to a welding method, in which at least two different welding processes can be combined. According to the invention, such a welding unit (27) and welding method can be achieved, in which the amount of introduction of additional material and the heat or energy supply into the workpiece (16) may be adjusted as independently from each other as possible, whereby the first welding burner (10) is embodied for carrying out a welding process and at least one second welding burner (35) is embodied for carrying out a cold metal transfer welding process with a back-and-forth movement of a welding rod (32) and for synchronisation of the welding processes carried out with the at least two welding burners (10, 35).

Welding unit and welding method by means of which at least two different welding processes may be combined

Disclosed is a method for hybrid welding in which a laser beam is applied to the welding position of objects to be welded, and at the same time, a first wire is fed to the welding position so as to perform arc welding using an arc generated between the objects to be welded and the first wire. In this method, one or more second wires are fed to a molten weld pool formed by the laser beam and arc welding, thereby increasing the amount of welding without increasing the arc current.

Hybrid welding method and hybrid welding apparatus

The invention relates to a method for welding coated sheet metal (3) by way of a laser hybrid welding method, whereby at least one laser method and one shielded arc-welding method are carried out, and a weld metal (12) is supplied to the weld by way of the shielded arc-welding method. The invention also relates to a laser hybrid welding torch for welding coated sheet metal (3), which comprises at least one laser (13) and at least one shielded arc unit (5) and a rod feeding device (11) for a welding rod (12). The aim of the invention is to provide a method or a device of the aforementioned kind which allows for reducing or completely avoiding inclusions such as are e.g. caused by the evaporation of the coating of the metal sheet (3). For this purpose, a clamping device (6) is used for positioning the coated metal sheet (3) without substantial gaps between the individual sheets. A material having a zinc and/or carbon and/or aluminum content is used as the weld metal or welding rod (12).

Laser Hybrid Welding Method and Laser Hybrid Welding Torch Using a Zinc and/or Carbon and/or Aluminum-Containing Rod

A hybrid welding from a combination of laser beam welding with gas-shielded welding by electric arc uses at least two electrodes are used The electrodes can be flooded by a common shielding gas curtain or separately or in groups The hybrid welding increases the possibility of influencing the welding process and especially provides improved possibilities for automation

Method and apparatus for hybrid welding under shielding gas

The invention relates to a shielding gas for arc-welding metal workpieces The invention also relates to a method for arc-welding metal workpieces using a melting electrode, whereby a stream of shielding gas adjacent to the electrode is fed onto the workpiece For the MSG welding, preferably MAG welding of stainless steel, in particular of nickel-based material, special steel or special alloy steel, the invention recommends shielding gases, which in addition to argon, nitrogen and optionally helium contain, a) a proportion of carbon dioxide between 0001 and 19 % by volume, (if the shielding gas contains no helium) and b) a proportion of carbon dioxide between 0001 and 09 % by volume, (if the shielding gas also contains helium)

Shielding gas and arc-welding method

A shielding gas for d.c. TIG welding of aluminum consists of helium, optionally argon and a small quantity of nitrogen. A shielding gas for d.c. TIG welding of aluminum consists of either (a) helium containing 525-1000 vol. ppm nitrogen or (b) helium and argon containing 500-1000 vol. ppm nitrogen. An Independent claim is also included for d.c. TIG welding of aluminum using the above shielding gas.

Shielding gas for direct current TIG-welding of aluminium

Die Erfindung betrifft ein Schutzgas und ein Verfahren zum WIG-Gleichstromschweisen von Aluminiumwerkstoffen und Aluminiumlegierungen, wobei das Schutzgas der Schweisstelle zugefuhrt wird und wobei das Schutzgas im wesentlichen Helium oder ein Gemisch aus Helium und Argon enthalt. DOLLAR A Erfindungsgemas werden gute Schweisergebnisse mit einem Schutzgas erzielt, welches entweder neben Helium kein Argon und zumindest einen Anteil von 275 vpm bis 475 vpm Stickstoff oder neben Helium und Argon zumindest einen Anteil von 275 vpm bis 500 vpm Stickstoff enthalt. DOLLAR A In Ausgestaltung der Erfindung enthalt das Schutzgas zwischen 300 vpm und 450 vpm Stickstoff. Das Schutzgas weist bevorzugt zumindest 45 Vol.-% Helium auf. Dem Schutzgas konnen als aktive Komponenten 0,01 bis 1 Vol.-% Sauerstoff, Kohlendioxid oder einer Mischung aus Sauerstoff und Kohlendioxid zugemischt sein.

Schutzgas zum WIG-Gleichstromschweißen von Aluminium

Hybrid welding comprises guiding a focussed laser beam onto a moving workpiece and producing an electric arc between an electrode and the workpiece. The axis of the arc is concentric to the laser beam. An Independent claim is also included for an apparatus for hybrid welding comprising a laser beam head for introducing the laser beam to the workpiece; a welding burner for producing an electric arc between the electrode and the workpiece; and a device for producing relative movement between the laser beam head and the burner on one side and the workpiece on the other side, the axis of the arc being concentric to the laser beam.

Hybrid welding comprises guiding a focussed laser beam onto a moving workpiece and producing an electric arc that is concentric to the laser beam between an electrode and the workpiece

Stefan Trube

Papers

Method and apparatus for hybrid welding under shielding gas

Shielding gas and arc-welding method

Shielding gas for direct current TIG-welding of aluminium

Schutzgas zum WIG-Gleichstromschweißen von Aluminium

Hybrid welding comprises guiding a focussed laser beam onto a moving workpiece and producing an electric arc that is concentric to the laser beam between an electrode and the workpiece