A swing/rotating gas metal arc welding torch, include a hollow shaft motor and a feeder panel. An upper extending shaft of the feeder panel penetrates through a brush mechanism, and is fixedly connected to a lower extension shaft of the hollow shaft by means of a coupling, and a lower extending shaft of the feeder panel penetrates through a support bearing mounted in a brush base and is then connected to an eccentric or bent conductive rod mechanism; the motor base is fixedly connected to the brush base by means of connecting screws, and a welding shielding gas is provided and welding torch cooling is achieved by means of inner holes of the connecting screws as well as a built-in gas passage and a cooling water passage of the brush base; the length of the conductive rod mechanism is adjusted by means of modulation or extension and retraction.

A swing/rotating gas metal arc welding torch, include a hollow shaft motor and a feeder panel. An upper extending shaft of the feeder panel penetrates through a brush mechanism, and is fixedly connected to a lower extension shaft of the hollow shaft by means of a coupling, and a lower extending shaft of the feeder panel penetrates through a support bearing mounted in a brush base and is then connected to an eccentric or bent conductive rod mechanism; the motor base is fixedly connected to the brush base by means of connecting screws, and a welding shielding gas is provided and welding torch cooling is achieved by means of inner holes of the connecting screws as well as a built-in gas passage and a cooling water passage of the brush base; the length of the conductive rod mechanism is adjusted by means of modulation or extension and retraction.

A GTAW system and a welding method suitable for ultra-narrow gaps, and belongs to the technical field of narrow gap welding. The device includes a argon arc welding machine, a GTAW torch, a welding trolley, a wire feeding device, and a gas protection device. The GTAW torch includes a rotating motor, a rotating tungsten, a conductive system, and a gas supply system. The non-axisymmetric rotating tungsten is drived by the rotating motor through the central rotating shaft. The conductive system is used for connecting and supplying electric power from the argon arc welding machine, and the air supply system is used for providing shielding gas into the welding torch. The GTAW torch is fixed on the welding trolley, and the GTAW torch is moved by the welding trolley, and the wire feeding device moves synchronously with the welding torch.

The present invention relates to a process for manufacturing a Yankee cylinder. The process comprises welding the first reinforcement flanges of two workpieces of Yankee cylinder section from inside of the cylinder case, preheating and welding the two workpieces of Yankee cylinder section from outside of the cylinder case, and then removing the first, second reinforcement flanges, radial inner end area of the weld and their surrounding material in the workpieces of the Yankee cylinder section, so that the joint of the two workpieces of Yankee cylinder section is machined to meet the final dimension requirements for the Yankee cylinder inner grooves. The present invention is also related to a workpiece of Yankee cylinder section used in the said process.

The disclosed technology relates generally to welding technologies and more particularly to electrode assemblies for arc welding, e.g., submerged arc welding. In one aspect, an electrode assembly for submerged arc welding (SAW) comprises a head portion and an extension portion that are arranged serially to feed a consumable electrode therethrough such that, during SAW, the head portion is disposed to be distal to an arcing tip of the consumable electrode and the extension portion is disposed to be proximal to the arcing tip of the consumable electrode. The head portion includes a contact tip configured to electrically contact the consumable electrode to deliver power thereto. The extension portion is formed of a single piece insulating article configured for the consumable electrode to finally pass through before the arcing tip is exposed.

Weld metals and methods for welding ferritic steels are provided. The weld metals have high strength and high ductile tearing resistance and are suitable for use in strain based pipelines. The weld metal contains retained austenite and has a cellular microstructure with cell walls containing lath martensite and cell interiors containing degenerate upper bainite. The weld metals are comprised of between 0.02 and 0.12 wt % carbon, between 7.50 and 14.50 wt % nickel, not greater than about 1.00 wt % manganese, not greater than about 0.30 wt % silicon, not greater than about 150 ppm oxygen, not greater than about 100 ppm sulfur, not greater than about 75 ppm phosphorus, and the balance essentially iron. Other elements may be added to enhance the properties of the weld metal. The weld metals are applied using a power source with current waveform control which produces a smooth, controlled welding arc and weld pool in the absence of CO.sub.2 or oxygen in the shielding gas.

A system may include a current source; a first metal or alloy component with a first major surface electrically coupled to the current source; a second metal or alloy component with a second major surface electrically coupled in series to the first component and the current source via an external electrical conductor, where the first and second major surfaces are positioned adjacent to each other to define a joint region; a metal or alloy powder disposed in at least a portion of the joint region; and a controller. The controller may be configured to cause the current source to output an alternating current that conducts through the first component and the second component to induce magnetic eddy currents, magnetic hysteresis, or both within at least a portion of the metal or alloy powder disposed in at least the first portion of the joint region.

Provided are a welding apparatus and a method, including a welding torch, a wire nozzle, a support stand that supports the welding torch and the wire nozzle with a predetermined distance therebetween, and a first support mechanism that supports the support stand so that the support stand is rotatable around a first support axis that is along a direction in which the welding torch and the wire nozzle are arranged.

A stainless steel weldment and pad combined welding method includes steps of: (a) respectively processing and pairing butts of to-be-welded portions of two weldments, wherein, during pairing, inner walls of the two weldments are aligned at the same plane; the butts of the two weldments are opposed to form a V-shaped groove with an angle α; and between bottoms of the butts of the two weldments is kept a gap L of 2-4 mm; (b) providing a copper pad at the gap between the bottoms of the butts of the two weldments, wherein the copper pad closely attaches to the inner walls of the two weldments; (c) welding the V-shaped groove to form a root pass; and (d) removing the copper pad, and filling the root pass to be welded into a cover pass.

A welding system includes at least one high intensity energy source to create a weld puddle during a root pass on a narrow joint of a workpiece with a clad layer. The system also includes a controller to control a weld ramp out process such that, as the molten puddle advances to a start of an existing root pass weld, the controller at least one of decreases an energy output of the at least one high intensity energy source and reduces an interaction time between the at least one high intensity energy source and the weld puddle. After completion of the root pass, a thickness of a root pass weld in a region that is at or near the start point of the existing root pass weld is in a range of 100 percent to 130 percent of a nominal root pass thickness of a remainder of the root pass weld.