363 results about "Tungsten electrode" patented technology

The invention discloses a laser-hollow tungsten electrode arc coaxial composite welding torch, which relates to the technical field of welding, and comprises a hollow tungsten electrode, a plurality of cavities and a plurality of laser beams, and the laser beams are welded under the gathering action of a first laser beam arranged in the hollow tungsten electrode, an arc of the hollow tungsten electrode and a second laser beam positioned on the periphery of the hollow tungsten electrode and arranged in a second cavity. The welding energy of the laser-hollow tungsten electrode coaxial hybrid welding torch can be greatly improved; impurities such as an oxide layer, dust and attachments of the to-be-welded plate can be cleaned by arranging a third laser beam on the periphery; the welding wire is spirally arranged in the sixth cavity, so that the integration level of the composite welding torch is improved, and meanwhile, the welding quality is better guaranteed; and by arranging the fourth cavity, under the action of the hollow fan, impurities generated by cleaning of the third laser beam can be pumped away, plasma plume generated by the plume effect generated in the welding area can also be pumped away, laser energy loss is avoided, and the welding quality is effectively guaranteed.

This application relates to a laser-plasma composite cladding head and a composite cladding method, and belongs to the field of surface processing of metallic materials. In the laser-plasma composite cladding head of this application, a ring laser beam is split into two half-ring laser beams through an upper roof lens to avoid a tungsten electrode. The two half-ring laser beams pass through a left 45° reflective lens to be coaxial with the tungsten electrode and then are integrated into a complete ring laser beam through a lower roof lens, thereby allowing a coaxial output of the ring laser beam and a plasma beam. This application integrates the advantages of laser cladding and plasma cladding and adopts coaxial compounding and synchronous powder-feeding.

The invention relates to a low-power pulse laser-induced enhanced double-TIG (Tungsten Inert Gas) composite heat source medium-thickness plate narrow-gap efficient welding method, which adopts two independent TIG welding machines, a pulse laser and a wire feeder, and two TIG welding guns are positioned in a narrow-gap groove on the same side of a plane on which a laser beam perpendicular to the plate welding direction is positioned, the angle and distance of each heat source can be independently adjusted, before welding, the space angle and distance among the two TIG welding guns, laser beams and welding wires are adjusted, tungsten electrodes at the front ends of the two TIG welding guns and the laser beams emitted by a laser device are arranged in the corresponding space range, and a plate to be welded and the welding wires can obtain sufficient heat for melting, wetting and spreading; during welding, welding parameters are adjusted, the coupling plasma energy density in the narrow gap space range is controlled, and the droplet transition behavior of a welding wire and the flow characteristic of a molten pool are adjusted and controlled in real time. Compared with traditional arc welding, the welding process window can be improved, and the welding deposition efficiency is improved by more than 10 times.

The utility model discloses an automatic tungsten electrode replacing device which comprises a device base, a first electrode, a second electrode, a third electrode and a fourth electrode. At least part of the tungsten electrode storage warehouse is arranged in the containing space, the tungsten electrode storage warehouse comprises a rotating assembly and a plurality of tungsten electrode storage pieces, each tungsten electrode storage piece is configured to store a tungsten electrode, and each tungsten electrode storage piece is arranged on the rotating assembly so as to rotate along with the rotating assembly; the rotating driving mechanism is arranged in the accommodating space and is configured to be in driving connection with the rotating assembly; the tungsten electrode moving mechanism is arranged in the containing space, and the tungsten electrode moving mechanism is configured to enable the tungsten electrode in the at least one tungsten electrode storage part to move to a first position in the first direction; wherein the tungsten electrode located at the first position is configured to be replaced by a tungsten electrode replacement robot. According to the automatic tungsten electrode replacing device, the requirement for automatically replacing the tungsten electrode in the market is met through the simple structure and the low equipment cost.

The invention relates to the technical field of electric arc welding equipment, and provides electric arc welding equipment for automobile part machining, which comprises a welding head seat, a tungsten electrode welding needle is detachably fixed at the bottom end of the welding head seat, and a gas spraying assembly for spraying protective gas is fixed at the top of the outer side of the welding head seat. The outer side of the welding head base is sleeved with a protection assembly for protecting the tungsten electrode welding needle. The mounting column is fixed at the top end of the welding head seat; by means of the technical scheme, the problems that in the prior art, electric arc welding equipment is not provided with an effective protection mechanism, a tungsten electrode welding needle is exposed outside for a long time and is prone to being impacted to be damaged in the idle or non-working state, an air injection pipeline is usually of a fixed structure, an air cut-off plugging mechanism is lacked, and the equipment is damaged are solved. The diameter of a welding wire guide pipe of an existing electric arc welding device is fixed, the welding wire guide pipe can only adapt to welding wires with one diameter, effective adjustment cannot be conducted according to different welding wire diameters, and the capacity of the welding wire guide pipe for adapting to complex workpieces or various types of welding wires is limited.

The invention provides a positive and negative pressure pulse electric arc welding and additive manufacturing method which comprises the following steps: inducing electric arc plasma to generate a negative pressure electric arc with an anti-gravity adsorption effect through a current-magnetic field-hollow tungsten electrode-gas collaborative design, and forming a time sequence coupling process with a positive pressure electric arc. The core of the method is that a magnetic control positive pressure and negative pressure electric arc welding external field is cooperated with a molten pool reconstruction forming mechanism, that is, the dynamic and thermodynamic states of a molten pool are accurately balanced by dynamically switching the electric arc pressure direction and regulating and controlling the action proportion and alternating frequency of negative pressure and positive pressure electric arcs. A self-adaptive magnetic field threshold model based on current intensity and a gas mode is combined with variable polarity power supply parameters and gas flow rate cooperative control, and the problems of thin plate welding fusion penetration and thin-wall additive molten pool instability are effectively solved. According to the method, a welding wire, powder or laser composite manufacturing mode can be integrated, the forming precision and performance of a complex structure are remarkably improved, and an innovative technical support is provided for high-quality and high-efficiency welding and additive manufacturing.

Disclosed handheld welding devices include: an energy storage device; power conversion circuitry configured to convert input power from the energy storage device to output welding power; a wire feeder configured to deliver welding wire and / or a gas valve configured to control flow of gas from a gas source; a front assembly configured to conduct the welding power to a welding electrode, wherein the front assembly is swappable between two or more of a wire-fed welding process, a stick welding process, or a tungsten electrode welding process; control circuitry configured to control the power conversion circuitry and the at least one of the wire feeder or the gas valve based on the configured one of the two or more welding processes, to selectively provide the welding power and at least one of the welding wire or the gas to the front assembly in response to an input device; and a housing.

The invention provides an argon arc welding tungsten electrode appearance defect detection method and system and a storage medium, and relates to the technical field of tungsten electrode appearance detection.The method comprises the steps that firstly, a sample electrode with known defects is subjected to three-dimensional scanning and discretization into a plurality of space points, and each point is endowed with a defect existence mark; by applying a composite sine wave excitation current, an eddy current signal generated when a collector spirally passes through a detection coil at a constant speed is acquired, and laser ultrasonic scanning is synchronously utilized to acquire full-matrix data and reconstruct a three-dimensional gray model. And constructing a double-branch deep learning model, fusing the eddy current feature vector and the ultrasonic image block feature, and learning a mapping relationship between the eddy current feature vector and the defect mark. And performing the same detection on a to-be-detected electrode, outputting the defect confidence of each position by using the trained model, calculating a comprehensive quality index in combination with a preset defect severity weight and a spatial key region weight, and judging whether the electrode is qualified or not according to a qualified threshold value. According to the invention, high-precision, automatic and comprehensive detection of surface and internal defects is realized.

The invention provides an auxiliary fluid director for protective gas and a welding device, and relates to the technical field of welding protection, a tungsten electrode is arranged at the tail end of a welding gun body, and the auxiliary protective gas fluid director comprises a gas storage enclosure piece fixedly arranged on the periphery of the welding gun body in a sleeving mode, a gas storage cavity is formed between the inner wall of the gas storage fence piece and the outer wall of the welding gun body, and an outlet is formed in the end, facing the tungsten electrode, of the gas storage cavity. The gas sieve is fixedly arranged at the outlet of the gas storage cavity; the gas supply assembly is communicated with the gas storage cavity and is used for supplying protective gas to the gas storage cavity; and the nozzle clamp is fixedly arranged on the outer side of the gas storage enclosure piece, a gap is formed between the nozzle clamp and the gas storage enclosure piece, and the gap extends in the axis direction of the tungsten electrode. The action range of the protective gas can be adjusted, and the welding quality is guaranteed.

The invention discloses an electric arc additive manufacturing method for assisting in titanium alloy grain refinement through coaxial ultrasound. The method comprises the following steps that firstly, an ultrasonic gun is installed on a welding gun in the mode that the ultrasonic gun and a tungsten electrode are coaxial; 2, fully cleaning the surface of the titanium alloy substrate, clamping and fixing the titanium alloy substrate in a to-be-welded area, and adjusting the tip position of a tungsten electrode to the initial position of material increase; thirdly, welding shielding gas is introduced in advance, and after the electric arc is stable, layer-by-layer stacked additive manufacturing is carried out on the titanium alloy substrate through a coaxial ultrasonic auxiliary method; and fourthly, the titanium alloy component obtained after additive manufacturing is completed is cooled and then taken down from the clamp, and the additive manufacturing process is completed. According to the method, the ultrasonic waves are introduced into the electric arc and the molten pool, the electric arc form can be effectively controlled, the fluidity of the molten pool can be effectively improved, then grain size refinement and distribution uniformity of the titanium alloy additive manufacturing component are achieved, the titanium alloy additive manufacturing component is strengthened, the mechanical property of the titanium alloy additive manufacturing component is improved, and the method has very important significance on titanium alloy electric arc additive manufacturing.

The invention relates to the technical field of welding of a titanium alloy or titanium heat exchange tube and a tube plate, and discloses a welding method and a welding protection device for the titanium alloy heat exchange tube and the tube plate. 2, positioning and mounting the positioning shaft head; step 3, mounting and adjusting a main air tap; step 4, mounting and adjusting the auxiliary air tap; 5, welding the tube plate and the heat exchange tube; a welding protection device for welding a titanium alloy heat exchange tube and a tube plate mainly comprises a positioning shaft head, a main air tap, a tungsten electrode and an auxiliary air tap. The device has the beneficial effects that all-directional argon isolation air protection near a welding seam, a heat affected zone and a welding zone in the welding process of the tube plate and the heat exchange tube is achieved, and the protection range of argon in the welding process is enlarged; and the uniformity, compactness and strength of the welding seam are improved, the forming quality of the welding seam is improved on the whole, and a silver welding joint is obtained.

The invention discloses a method for determining the offset distance of a welding gun of a metal plate welding case lock bottom welding seam and a welding method, and belongs to the technical field of fusion welding technologies. The method for determining the offset distance of the welding gun comprises the steps that the machining side welding thickness L1, the metal plate side welding thickness L2 and the bottom locking thickness L3 of the metal plate welding case are obtained, and the axis offset P of a welding gun tungsten electrode and the center of a welding connector is calculated; based on the axis offset P, the opposite position of a welding gun tungsten electrode is determined, the offset angle theta over a welding bead and the diameter phi A of the welding bead are obtained, and the offset distance L between the opposite position of the welding gun tungsten electrode and the position over the welding bead is calculated; and based on the axis offset P of the welding gun tungsten electrode and the center of the welding joint and the offset distance L between the position right opposite to the welding gun tungsten electrode and the position right above the welding bead, the alignment position line of the tip end of the welding gun tungsten electrode is determined at the workpiece welding joint. The welding method comprises the steps that the position of the circumferential automatic welding gun mechanism is adjusted based on the alignment position line, and a welding gun is located in the welding bead upslope direction in the circumferential direction.

The utility model discloses an ultrasonic wire feeding additive manufacturing device which comprises a base plate, a tungsten electrode welding gun, a wire feeder and an ultrasonic vibration system. The tungsten electrode welding gun, the wire feeder and the ultrasonic vibration system are jointly connected with a positioning rod, and the positioning rod is movably arranged above the base plate. The ultrasonic vibration system is located on one side of the wire feeder and used for generating high-frequency vibration signals and transferring the generated high-frequency signals to a welding metal wire. According to the ultrasonic wire feeding additive manufacturing device, ultrasonic vibration is applied to the welding metal wire, so that a high-frequency vibration signal is transmitted into the molten pool through the welding metal wire, cavitation is generated in the molten pool, beta columnar crystals generated in the solidification process can be effectively broken, and the production efficiency is improved. And the anisotropy problem of the internal structure and the mechanical property in the wire feeding direction and the stacking direction is solved, that is, the performance of an additive manufacturing part is improved.

The invention discloses a tungsten-based heavy alloy surface-coated stainless steel component and a preparation method and application thereof, and belongs to the technical field of metal connection. The preparation method of the component with the tungsten-based heavy alloy surface coated with the stainless steel comprises the following steps that a transition layer is additionally attached to the surface of tungsten-nickel-iron alloy; the tungsten-nickel-iron alloy with the transition layer and austenitic stainless steel are assembled, and a sheath assembly is obtained; carrying out degassing and hot isostatic pressing treatment on the sheath assembly; according to the preparation method of the component coated with the stainless steel on the surface of the tungsten-based heavy alloy, the tungsten-based heavy alloy and the austenitic stainless steel are used as matrixes, and preparation of the component coated with the tungsten-based heavy alloy through the austenitic stainless steel is achieved through the method of combining hot isostatic pressure diffusion bonding and powder metallurgy. An existing technology that a stainless steel shell is used for protecting tungsten-based heavy alloy and an end socket is closed in an argon tungsten-arc welding mode is replaced, an original assembly gap is removed through metallurgical bonding, and the whole running-down system is more stable in operation and better in corrosion resistance.

The invention belongs to the technical field of welding, and particularly relates to an online repair welding device for a gate valve seat. Comprising a mechanical body, an adapter, a welding power source, an upper computer, an argon bottle and a pipeline, the mechanical body is connected with the welding power source through the pipeline, the welding power source is connected with the upper computer and the argon bottle through the pipeline, and the mechanical body is installed on a valve through the adapter. The invention has the following beneficial effects: light weight design is adopted, so that carrying is convenient; welding operation can be remotely controlled; the structure is compact, and welding operation in narrow space in the valve can be met; welding of valve seats of different models and different diameters can be adapted by replacing the adapter; the states of welding wires, tungsten electrodes and molten pools can be remotely observed, and the welding quality is guaranteed.

The invention relates to the technical field of dissimilar material welding, and provides a red copper and stainless steel weldment and argon tungsten-arc welding process, which comprises the following steps of: selecting stainless steel and red copper with the thickness of more than or equal to 1mm and less than or equal to 3mm as a to-be-welded workpiece, oppositely butting the stainless steel and the red copper, controlling the width of a gap at the butting part of the stainless steel and the red copper, and forming a V-shaped groove at the butting part of the stainless steel and the red copper; the butt joint of the back faces of the red copper workpiece to be welded and the stainless steel workpiece to be welded is subjected to positioning spot welding; after tack welding, in an argon shielding gas atmosphere, a tungsten electrode is used as a welding heat source, a direct current positive connection mode is adopted for conducting backing welding on the butt joint position, only the tungsten electrode is used for heating in the welding process, the tungsten electrode is close to the side of the stainless steel workpiece to be welded, and welding wire filling is avoided; and after backing welding, the V-shaped groove is filled with a welding wire in the argon shielding gas atmosphere, and then a tungsten electrode is adopted as a welding heat source to conduct cosmetic welding on a backing welding seam. The method has the characteristics of high welding quality, simple and convenient welding process and relatively low cost.

The invention relates to the technical field of air cooler welding, in particular to an automatic welding device and process for an air cooler tube plate and a tube. The tube plate robot is movably arranged on the base, a welding machine head is arranged on the tube plate robot, and the welding machine head is used for welding a tube plate and a tube; the visual positioning camera is fixed on the tube plate robot and is positioned beside the welding machine head; the pipe plate robot welding work depends on the cooperation of the robot and the visual positioning camera, the efficiency is greatly improved, the touch locating function is achieved, the arc height and the arc starting radius can be automatically adjusted according to the actual condition of each pipe, and therefore the welding seam consistency is good; meanwhile, moving, starting and stopping of a welding head of the tube plate robot welding workstation are controlled by equipment, manual intervention is almost not needed, and the technical problems that in the prior art, shielded metal arc welding is greatly influenced by human factors, and the manual participation degree of semi-automatic tube plate tungsten electrode argon arc welding is high are solved.

The invention discloses a manual tungsten electrode welding method for a zirconium pipe, relates to the field of zirconium pipe welding, and provides the following scheme for solving the problems that the zirconium pipe is a new material, few cases are referenced in the welding method, and no matched tool is used for matching so as to improve the welding efficiency. The method comprises the steps that firstly, two sections of zirconium pipes to be welded are clamped on a clamping and polishing tool, and groove machining treatment is conducted on the zirconium pipes to be welded till silver white is exposed on the surfaces; and 2, the two sections of zirconium pipes are assembled, then the assembled zirconium pipes are welded through a tungsten electrode welding gun, and the front face and the back face of a welding seam are protected through welding gun protection gas, zirconium pipe external protection gas and zirconium pipe internal protection gas in the welding process. According to the method, the measures of welding seam front face large nozzle protection and in-pipe argon filling welding seam back face protection are adopted, the protection effect on a high-temperature area welding seam and a heat affected area is ensured, the welding quality is ensured, the clamping and grinding tool is arranged, and the universality during zirconium pipe welding is remarkably improved.

The invention relates to the technical field of hybrid welding, in particular to a laser and TIG magnetic control hybrid welding process for a nickel-based alloy pipe production line, which comprises the following steps: pipe manufacturing, preparation, conveying and preheating, welding and cooling, equipment comprises a dust-free welding chamber and a welding pipe, a welding mechanism is arranged in the dust-free welding chamber, and the welding pipe is arranged in the dust-free welding chamber. The welding mechanism comprises a high-frequency pulse TIG welding gun and a laser transmitter, a magnetic field mechanism is arranged in the high-frequency pulse TIG welding gun, and a tungsten electrode end is arranged at the end, away from the adjusting frame, of the high-frequency pulse TIG welding gun. The method has the advantages that optical fiber laser welding is combined with the high-frequency pulse TIG arc and external alternating magnetic field technology, the welding speed is remarkably increased, rapid heating is achieved through optical fiber laser welding, the stirring and mixing effects of a molten pool are enhanced through adding of the high-frequency pulse TIG arc and the alternating magnetic field, the alternating magnetic field stirs the interior of the molten pool, grains are refined, and the overall performance of a welding seam is improved; therefore, thermal stress and deformation of weld metal are reduced, and welding efficiency and quality are improved.

The invention discloses a welding method for optimizing a welding seam structure of a nickel-based alloy composite board. The nickel-based alloy composite board comprises a base material layer and a nickel-based alloy composite material layer, and a transition layer is arranged at the bonding interface of the base material layer and the nickel-based alloy composite material layer; the welding method comprises the steps that a trapezoidal groove is machined in the position, corresponding to the base material layer, of the welding section of the nickel-based alloy composite board; a U-shaped groove is machined in the position, corresponding to the transition layer, of the welding section of the nickel base alloy; a groove is not machined in the position, corresponding to the nickel-based alloy composite material layer, of the welding section of the nickel-based alloy composite plate, and a truncated edge is reserved; welding the nickel-based alloy composite material layer by adopting single tungsten electrode argon arc welding; welding the transition layer by adopting single tungsten electrode argon arc welding; and welding the base material layer by adopting single tungsten electrode argon arc welding.

The invention discloses a gradient preparation method of a compact barrier type rare earth ceramic coating, and belongs to the technical field of high-temperature protective coatings. The preparation method comprises the following steps: pretreating a tungsten electrode substrate; sequentially preparing a sensor layer integrated with a distributed optical fiber sensor, a gradient transition layer which is realized by adopting a four-channel synchronous powder feeding technology and has continuous and gradual components, and a self-adaptive layer which is prepared by adopting a laser-induced in-situ synthesis technology and contains high-entropy rare earth zirconate and an intelligent additive; the self-healing layer contains a triple temperature triggering microcapsule system; and finally, post-processing and function activation are carried out. The prepared coating forms an intelligent response type gradient composite structure from inside to outside, has excellent interface bonding strength, thermal shock resistance and high-temperature chemical stability and has damage self-healing and service state real-time monitoring functions, and the service life of the tungsten cathode under the severe working condition is remarkably prolonged.

The invention relates to the field of GTAW filling wire control, in particular to a GTAW liquid bridge transition closed-loop control system based on vision and electric arc cooperative sensing. The GTAW liquid bridge transition closed-loop control system based on vision and electric arc cooperative sensing is a GTAW liquid bridge transition closed-loop control system based on vision and electric arc cooperative sensing. Aiming at keeping a continuous liquid bridge transition mode for welding in a GTAW process, the invention provides a GTAW liquid bridge transition closed-loop control system based on visual sense and electric arc cooperative sensing. A GTAW robot is used for controlling the welding action; shooting a GTAW droplet transition process by using a droplet transition image acquisition system; an arc voltage signal between the welding wire end and the workpiece and an arc voltage signal between the tungsten electrode tip and the workpiece are collected through an arc signal collecting system; identifying a liquid bridge transition mode by using a GTAW liquid bridge transition mode identification system; a filling wire height control system is utilized to enable a liquid bridge transition mode to be a continuous liquid bridge transition mode.

The invention discloses an infrared induction feedback type permanent magnet magnetic field auxiliary TIG (Tungsten Inert Gas) welding device and a working method thereof, and the device comprises a TIG welding gun arranged above a workpiece, a welding power supply connected with a tungsten electrode in the TIG welding gun, a permanent magnet group arranged above the workpiece, and a magnet driving mechanism for driving the permanent magnet group, the infrared temperature detector is arranged on the side surface of the workpiece; the driving permanent magnet set and the infrared temperature detector are both connected with the control system, the infrared temperature detector detects the arc temperature distribution condition in real time and feeds back the detected arc temperature to the control system, and the control system compares the arc temperature with a preset threshold value and sends a control signal to the magnet driving mechanism according to the comparison result. The magnet driving mechanism adjusts the distance between the two permanent magnets in the permanent magnet group and the electric arc based on the control signal, and dynamic adjustment of the magnetic field intensity is achieved. According to the invention, the size of the magnetic field can be flexibly changed, and high energy consumption and electromagnetic interference of the electromagnetic coil can be avoided.

The invention belongs to the technical field of underwater welding, and discloses an underwater double-path ultrasonic synergistic laser-electric arc hybrid welding repair device and method. The device comprises a two-way ultrasonic synergistic TIG welding gun and a laser head which are both fixed on an external drainage cover, and sealing penetration pieces are arranged on the external drainage cover for the two-way ultrasonic synergistic TIG welding gun and the laser head; the double-path ultrasonic synergistic TIG welding gun comprises a tungsten electrode sound path and an end part sound path; the tungsten electrode sound path transmits ultrasonic energy to a welding gun tungsten electrode through a tungsten electrode ultrasonic transducer, the electric field at the root of the welding gun tungsten electrode and the micro-motion behavior of the welding gun tungsten electrode are affected, and therefore the electric arc is compressed, and the position of the root of the electric arc is finely adjusted. The end sound path acts on the end of the welding gun through the end ultrasonic transducers in an annular array, directional sound radiation pressure is applied, an electric arc column and the surface of a molten pool are adjusted, heat input is promoted to be evenly distributed, and the symmetry of the molten pool is improved. The welding quality and the process stability are remarkably improved.

The invention provides a filler wire welding device. The wire filling welding device comprises a welding torch, a pipe fitting locking mechanism, a handle and a wire feeding mechanism. Wherein the pipe fitting locking mechanism is used for clamping a to-be-welded pipe fitting, and the pipe fitting locking mechanism clamping the to-be-welded pipe fitting forms a closed cavity at a weld joint of the to-be-welded pipe fitting. The welding torch comprises a tungsten electrode, the wire feeding mechanism is filled with a welding wire matched with the welding seam filling amount, and the tungsten electrode, the wire feeding mechanism and the welding wire are located in the closed cavity in the welding process. The tungsten electrode and the wire feeding mechanism can rotate in the circumferential direction of the pipe fitting to be welded so as to weld a weld joint of the pipe fitting to be welded in the closed cavity. According to the wire filling welding device, wire feeding in the welding process can be achieved on closed cavity welding equipment.

The invention belongs to the technical field of welding, and particularly discloses a solid welding wire fusion repair welding method which comprises the steps that a to-be-fusion repair area is cleaned; the extending length of a tungsten needle on the argon tungsten-arc welding gun is adjusted not to exceed the inner diameter of a nozzle of the argon tungsten-arc welding gun; the height from the tungsten needle to the to-be-repaired area is adjusted to be a preset height, so that the electric arc does not deviate; the fusion repair included angle is adjusted to be within a first preset angle on the two sides of the weld toe included angle bisector; welding toes and plates around the welding toes are molten again through an electric arc, molten metal on the two sides of the welding toes is drained to the middle area through the surface tension of a molten pool after melting, and the surface of the solid welding wire welding seam is made to be smooth. By means of the method, a smooth transition area can be formed on the surface of the weld toe, the effect of stress concentration of the weld toe can be remarkably reduced, the weld bead shape can be finished by replacing a grinding machine with the method of weld toe fusion repair between layers, the incomplete fusion condition is reduced, and therefore the internal quality of the weld is improved.

The invention relates to the technical field of titanium and titanium alloy welding, and provides a titanium alloy annular seam efficient large-deposition vibration wire feeding narrow gap welding method, by innovatively designing an asymmetric inclined groove combined with an asymmetric arc swing and an asymmetric vibration wire feeding technology, by designing an asymmetric inclined groove between the upper and lower parts of the groove, the influence of gravity on the welding molten pool is effectively reduced; the asymmetric arc swing technology is adopted to extend the residence time of the tungsten electrode at the upper part of the groove to preheat the side wall, while shortening the residence time at the lower part, reducing heat input, and preventing the molten pool metal from dripping down; combined with the introduction of asymmetric vibration wire feeding technology, according to the different positions of the tungsten electrode at the upper and lower parts of the groove, the vibration mode of the welding wire is dynamically adjusted, the surface tension of the deposited metal is improved, the uniform spreading of the large deposited metal in the groove is promoted, and the flow of the molten pool is disturbed by vibration, the accumulation of the deposited metal at the lower part of the groove is effectively prevented, and the heat distribution and the molten pool behavior during welding are optimized.

The invention provides an electric arc additive manufacturing system and method based on discontinuous pulse cold welding. The system comprises a discontinuous pulse cold welding gun, a wire feeding guide pipe, a wire feeder and a multi-axis motion platform. The discontinuous pulse cold welding gun is connected with a wire feeder based on a wire feeding guide pipe and installed on the multi-axis motion platform. An electric arc welding wire and a discontinuous pulse cold welding gun are sequentially assembled from front to back; a tungsten electrode of the discontinuous pulse cold welding gun is connected with a negative electrode of the cold welding power source, and the titanium alloy welding wire is connected with a positive electrode of the cold welding power source. According to the method, through the discontinuous pulse cold welding technology, the titanium alloy structural part with the fine-grain weak texture characteristic can be formed in the electric arc additive manufacturing process through simple and convenient equipment and structure; the fine-grain weak texture structure can remarkably improve the strength, toughness and fatigue resistance of the titanium alloy, and has important significance in application of high-performance titanium alloy components in the fields of aerospace, weaponry and other major equipment.

The invention belongs to the technical field of welding, and particularly relates to a sealing welding method for a nuclear power spent assembly overhanging type pipe and pipe plate. Positioning expansion is carried out by adopting a mechanical method; automatic TIG helium arc welding is adopted for welding, helium and argon mixed gas serves as welding shielding gas, a cerium tungsten electrode serves as an electrode, and all-position rotary welding is conducted after arc starting. Spot welding is replaced by mechanical expansion, and almost no gap exists between the tube and the tube plate, so that the welding method is more stable; according to the method, the welding quality is stable (the minimum leakage drift diameter of the root is stable, and welding defects do not exist), the welding efficiency is high (the welding efficiency is two times that of conventional argon arc welding), and the method has important significance on nuclear power outward-extending pipe and pipe plate seal welding.

According to the welding process for the 316LN austenitic stainless steel, the welding process is suitable for the ultralow temperature (-269 DEG C) environment, the multi-layer manual argon tungsten-arc welding (GTAW) technology is adopted, postweld heat treatment is not needed, the production process is simplified, and the cost is reduced. And by accurately controlling welding heat input, it is ensured that a welding joint has excellent toughness at the low temperature, and grain coarsening and harmful intermetallic phase precipitation are avoided. Nitrogen-strengthened 316LN base metal and a low-carbon and high-molybdenum GTS-316LM welding wire are selected, and the low-temperature strength and corrosion resistance of a welded joint are improved. Oxides and slag inclusion in the welding seam are reduced through high-purity argon protection, and the quality of the welding seam is optimized. Metallurgical bonding of welding seams is ensured through the interlayer cleaning process. Tests show that a welded joint shows excellent impact toughness and room-temperature mechanical properties at the temperature of-269 DEG C, and the ultralow-temperature application requirement is met. The process does not need postweld heat treatment, has the advantages of simplifying production, reducing cost and improving performance, and is suitable for equipment manufacturing and pipeline installation at the liquid helium temperature.