298results about How to "Reduce welding defects" patented technology

A compound welding method by using semiconductor laser and CO2 laser comprises the steps: using a semiconductor laser and a CO2 laser to be positioned on one side of a welding line of welded metals in a certain angle, adjusting a focusing position of the CO2 laser to cause a light spot of the CO2 laser to be positioned in the light spot of the semiconductor laser so that the welding direction is consistent with the slow axis direction of the semiconductor laser; using the semiconductor laser to pre-heat the welded metals, heating the part to be welded entering into the light spot of the semiconductor laser to 200-400 DEG C, using the CO2 laser to weld, and performing a post-welding thermal treatment to the welded metals by using the semiconductor laser for the welded parts of the welded metals welded by the welding of the CO2 laser. Due to synchronous pre-heating and post-heating treatments to the welding process, the invention can effectively solve the problem of cold cracking in high-strength steel welding and improve the quality of high-strength steel laser welding.

The invention discloses a hybrid welding method and hybrid welding equipment for laser electromagnetic pulse. The method can be used for laser seam welding and laser spot welding technology, a pulsed high magnetic field is applied to a welding region during the process of laser welding on a workpiece with the effect of laser beams so as to mutually react with an induced plasma, a welding pool and a stress strain field through welding and complete welding task. The equipment comprises a laser device, an electromagnetic pulse generator, a numerical control system, an optical transmission system and a laser electromagnetic pulse combined machining head. The combined machining head is used for integrating the laser beams with the pulsed high magnetic field and adjusting the distance between an electromagnetic conversion device and the workpiece; the combined machining head is arranged on a machine tool. The structural deformation can be reduced, the welding quality and machining efficiency are improved, and insurmountable technical problems when a metallic material structure is manufactured through existing single welding technology are solved.

The invention relates to a method for deep penetration laser welding of a plate under the assistance of ultrasound. The method is characterized by comprising the following steps that firstly, first base metal (10) and second base metal (11) are machined to form butt joint end faces, and a series of inclined semicircular grooves are machined; secondly, the first base metal (10) and the second base metal (11) are in butt joint and are clamped, and a series of inclined blind holes are formed in a weld bead; thirdly, a first ultrasonic amplitude-changing rod (3) is pressed to the upper surface of a workpiece to be welded; fourthly, a second ultrasonic amplitude-changing rod (4) is fixed to one side of a laser welding head; fifthly, an ultrasonic generation device is started, the ultrasonic frequency is adjusted; sixthly, a laser beam (5) perpendicularly irradiates the upper surface of the workpiece, and the welding process is completed under continuous ultrasonic vibration; and seventhly, after welding is completed, ultrasonic vibration is maintained for 1-2 minutes. In the method, due to the pre-formed inclined blind holes and ultrasonic vibration, weld joint root leakage caused by molten pool downward flowing driven by local evaporation back flushing pressure of the front edge walls of the small holes is avoided.

The composite rotary double focus laser-MIG electric arc welding head includes mainly two parts, the rotary double focus laser welding head and the MIG electric arc welding wire feeding welding gun, connected via a connecting plate. It has welding wire feeder fixed on the connecting plate, welding wire feeding hose connected to the feeder, conducting nozzle and goose neck for welding wire to pass through; protecting nozzle in the end of the goose neck; and rotating table with reflecting cavity, regulating frame, reflector, connecting barrel and welding laser head. The present invention combines the rotary double focus laser welding and the MIG electric arc welding, and has greatly raised welding performance and lowered assembling precision requirement for even wide application.

A stainless heat-proof self-protecting flux-cored wire for a magnesium smelting reduction tank belongs to the technical field of materials processing engineering. A normal stainless steel band 304L or common carbon steel serves as a coating layer, and alloys in a powder core are rutile, sodium carbonate, feldspar, compound fluorides, chromium, nickel, manganese, molybdenum, chromium nitride, aluminium-magnesium alloy, misch metal and iron power. Compared with a conventional stainless steel welding rod, the stainless heat-proof self-protecting flux-cored wire has the advantages that higher welding current can be used; higher welding speed can be realized; the production efficiency is improved; and the labor intensity is lowered; c. Compared with a conventional stainless steel submerged-arc welding solid wire, the stainless heat-proof self-protecting flux-cored wire has the advantages that all-position welding can be realized; the heat input is small; the slag detachability is good; and the manufacturing technique is simpler. A welded joint formed by using the stainless heat-proof self-protecting flux-cored wire provided by the invention has favorable heat resistance, oxidation resistance, vulcanization and corrosion resistance and high-temperature creep resistance compared with welded joints formed by welding the stainless steel welding rod and the stainless steel solid wire.

The invention discloses an intelligent online detection device based on multi-source information fusion for a welded joint. High-quality and time-varying infrared imaging information is acquired according to the welding residue temperature, an infrared light video and a visible light video of a real-time welded joint during the welding process are acquired through an infrared ray array sensor anda visible light camera, the fusion and the intelligent identification of two video information are realized through a video information acquisition module and an intelligent processing module, information such as the weld width, the center path, the welded joint texture and the surface temperature field distribution of the welded joint is acquired, and the quality of the welded joint is evaluatedby utilizing a deep learning algorithm; and the video information and a processing result are sent to a server through a wireless data transmission module, the image splicing and the matched fusing ofthe whole welded joint are carried out through the server according to the obtained infrared and visible light images of the welded joint, and a whole welding process quality evaluation database is built, so that a decision support is provided for welding process evaluation.

The invention relates to a semiautomatic argon tungsten-arc welding technological process of a bimetal compounding sea pipe, a labour hand-held semi-automatic welding gun welding is adopted, a wire feeder continuously feeds wires, and argon gas is utilized as protective gas. The technological process comprises the following operation steps of: firstly, procedure preparation before welding: manufacturing a groove, picking up fitting the groove, and selecting a welding material; secondly, backing welding process: adopting single layer one-pass welding, wherein two welders respectively stand thetwo sides of a welding seam so as to finish the backing welding; thirdly, hot-runner welding procedure: adopting single layer two-way welding and two-person welding; fourthly, filling welding procedure: adopting five-layer two-way welding and the two-person welding, and dismantling the protective gas after welding four layers; and fifthly, a cover surface welding process: adopting the single layer one-pass welding. The technological process provided by the invention has the advantages of high welding quality, small labour intensity, low construction cost, and high production efficiency; and the technological process is suitable for a compounding submarine pipeline and welding procedure of a subsidiary vertical pipe of the compounding submarine pipeline, and is suitable for the welding of a deep water composite material pressure container and deep water pipe manifold nickel base alloy and the like.

The invention discloses a preparation method for wear-resistant steel and carbon structural steel composite plates. The method includes the steps: processing a groove on each carbon structural steel plate according to the size of each wear-resistant steel plate, and cleaning the surfaces of the grooves and the wear-resistant steel plates; placing the wear-resistant steel plates into the grooves correspondingly, placing the wear-resistant steel plates and the carbon structural steel plates into a vacuum chamber in a clamping manner, performing seal welding for the bonding positions of the peripheries of the grooves with the wear-resistant steel plates to form wear-resistant steel plate blanks, and spraying high-temperature anti-adhesion coating on the bottom surfaces of the carbon structural steel plates; stacking the bottom surfaces of the carbon structural steel plates sprayed with the high-temperature anti-adhesion coating in two composite plate blank groups in a relative bonding manner, placing into the vacuum chamber in a clamping manner, and performing seal welding for the peripheries of the bonding surfaces of the two composite plate blank groups to form a combined blank; placing the combined blank into a heating furnace for heating prior to rolling; and conveying the rolled combined blank onto a roller type quenching machine for quenching prior to trimming so that the two wear-resistant steel and carbon structural steel composite plates are obtained. The method is capable of decreasing probability of welding defects and improving interfacial strength of the composite plates without changing performances of base plate layers, and is high in production efficiency.

The invention discloses a semi-automatic argon-arc welding method for bimetal composite pipes. The semi-automatic argon-arc welding method includes preprocessing orifices of welded pipelines; sequentially welding root welding layers, transition layers, filling layers and capping layers. The semi-automatic argon-arc welding method for the bimetal composite pipes has the advantages that difficult problems of low welding speeds, high labor intensity of workers and welding heat input quantities, influence on corrosion resistance of stainless steel layers and the like due to the fact that bimetal composite pipes are only welded and constructed manually can be solved, the problem of welding stress concentration at seal welding positions due to high welding head input for conventional cosmetic welding can be solved, the welding quality can be improved, and the welding speed can be increased.

A laser and electric-resistance seam-welding synchronous composite welding method for an envelope-framework structure relates to a novel laser and electric-resistance seam-welding synchronous composite welding method, belongs to the welding field, and aims to solve the problems in welding the envelope-framework structure by the single laser, such as narrow seam, low shear strength of the seam, a plurality of air vents on the faying surface of the envelope and the framework. The invention aims at the workpiece with the envelope-framework structure to be welded, and adopts the laser and the electric-resistance seam-welding synchronous composite welding; the electric-resistance seam-welding adopts double-roller single-side welding, two roller electrodes are disposed on the front and the back sides of the upper top surface of the envelope along the seam formed by the contact of the envelope and the framework, so that the envelope is pressed to the lower framework in the travel forward, and the laser beam is always positioned in the middle position of the two roller electrodes during the welding process. The seam formed by the welding method can improve the shear strength more than twice in comparison with the base material, and the air vent amount per area can be reduced from about 10% to about 2% of the laser welding.

The invention discloses a coaxial hollow tungsten electrode TIG device and a welding gun thereof, a using method and application and belongs to the technical field of electric arc additive manufacturing. The welding gun of the TIG device comprises a gun body and a hollow tungsten electrode, wherein the front end of the gun body is provided with a ceramic nozzle. The gun body is internally provided with a protective air cavity, and an air inlet hole communicated with the protective air cavity is formed in the gun body and used for being connected with an air source. The hollow tungsten electrode is arranged in the gun body, the front end of the hollow tungsten electrode extends out of the ceramic nozzle, and the middle of the hollow tungsten electrode is provided with a hollow wire feeding cavity. The side wall of the hollow tungsten electrode is provided with an air hole, and the air hole enables the wire feeding cavity of the hollow tungsten electrode to be communicated with the protective air cavity of the gun body. The welding gun is good in welding wire preheating effect, an additive manufacturing cracking phenomenon is avoided, the deposition efficiency is high, the welding speed is quick, weld defects are fewer, and the welding quality is high. According to the device, superspeed and high-quality electric arc additive manufacturing can be performed, and the device is particularly suitable for additive manufacturing of active metals such as copper and aluminum as well as alloy thereof. According to the using method, high quality weld joints can be obtained, and the welding quality is improved.

The invention discloses a metal inert gas (MIG) welding method of an aluminum alloy thin plate for a high speed train. The method is characterized in that an ER5356 welding wire and 99.9% argon protective gas are selected to conduct single pass welding. The method includes the following steps: 1) surface machining of a workpiece to be welded; 2) MIG welding; 3) welding gap defect checking. The step 1) includes that the workpiece to be welded is not preheated, an organic solvent is directly adopted to remove grease dirt and dust on the surface of the workpiece to be welded, and a mechanical method is adopted to remove an oxidation film on the surface of the workpiece in a washing mode. The step 2) includes that weld heat input is controlled between 4.0KJ/cm and 5.0KJ/cm during MIG welding, and environment humidity is controlled to be smaller than or equal to 70%. The step 3) includes that pore defects of a welded workpiece are removed through a steel wire brush or an air chipper. The method has the advantage that thin plate aluminum alloy welding connector pore welding hot crack number can be greatly reduced, welding gap forming is good, welding deformation is small, welding connector strength is higher, the MIG welding quality of the aluminum alloy thin plate for the high speed train is effectively improved, and welding quality stability is ensured.

The invention relates to a processing technology for refining weld joint structures in a welding process, in particular to a method and a device for refining weld joint structures by using pulsed magnet fields in the welding process, and belongs to the technical field of welding. The method for refining weld joint structures by using pulsed magnet fields in the welding process includes that welding is performed by using an ordinary gas metal arc welding method, an applied magnetic field is added above a gas metal arc welding pool, mechanical movement and welding gun movement of the magnet fields are synchronous, electric arc and melt drip transition action is controlled by the magnet fields in a welding process, metal melt in the gas metal arc welding pool is forced to move, an electromagnetic stirring effect is produced, and weld joint structures are finally refined in the welding process. According to the method and the device, in the welding process, the weld joint structures are refined, welding defects are reduced, and further the cost is reduced, and the welding quality and the production efficiency are improved.

The invention discloses a double-side double-arc welding process for a root layer of a pipeline, and the process comprises preparation before welding and backing welding. By utilizing the backing welding process of the double-side double-arc welding for the root layer of a pipeline disclosed by the invention, the inside and outside welding seams of the pipeline can be formed once, and the both surfaces of a molten pool for the pipeline are always in the protection of argon, so that the generation of air vents is avoided, the formation for the inside and outside welding seams of the pipeline is good, the dimensional requirements are relatively decreased due to assembly, the welding difficulty of welders is decreased, welding deformations are reduced, welding speed is increased, welding efficiency is increased, welding defects are reduced, energy and welding materials are saved, and welding cost is reduced. Simultaneously, by virtue of the design for the process parameters of a welding gun for the inside and outside of the pipeline, and under the action of the blowing force of double arcs, the flowability of metals in the molten pool is improved, the heat energy of the double arcs is adequately exerted, the penetration capacity is improved, and the welding characteristics of stainless steel are adapted, thus improving the quality of welding joints, and guaranteeing the welding quality.

The invention discloses a machining process of a propeller shell, comprising the following steps of: A, taking a steel plate and cutting the steel plate by a straight-line cutter or a cutting machine, so as to guarantee that the error degree of the cut steel plate is less than 2 mm; B, rolling the cut steel plate by using a rolling machine; C, butting and welding two ends of the rolled steel plate to form a cylinder, and carrying out nondestructive testing on a welding part; D, grinding a welding seam by using a grinding machine; and E, pressing and molding the grinded cylinder by using a mould to prepare the propeller shell. The machining process of the propeller shell has the advantages of improving the working efficiency and further improving the quality of products.