1488 results about "Shielding gas" patented technology

A laser welding nozzle includes: a beam guide member allowing a laser beam to pass therethrough and having a diameter that decreases toward a lower end thereof, with a beam discharge port formed at the lower end to have a smallest diameter; and a housing coupled to the beam guide member in such a manner that an inner surface of the housing faces an outer surface of the beam guide member to form a shielding gas line outside the beam discharge port and form a suction line connected to the beam discharge port.

The invention provides a self-adaptive teaching-free welding robot intelligent gas saving monitoring system, which relates to the technical field of industrial robots, and comprises a three-dimensional sensing module used for identifying the workpiece material category through a multispectral sensor integrated with a welding gun of a welding robot, meanwhile, a stereoscopic vision camera and a line structure light scanning camera are used for obtaining three-dimensional point cloud data of the welding seam in real time; the parameter adjusting module is used for calling a heat conductivity coefficient database based on the three-dimensional point cloud data, and correcting the initial flow of the welding current, the arc voltage and the protective gas in real time; and the matching control module is used for calculating the arc length variable quantity based on the arc voltage, controlling the opening degree of the gas flow valve through a dynamic regulator, realizing dynamic matching of the gas flow and the changed arc length, and generating gas dynamic matching control parameters. Through cooperative operation of self-adaptive attitude compensation and real-time gas consumption monitoring, teaching-free accurate operation in the welding process is achieved, and intelligent control over gas consumption is improved.

The invention discloses a steel structural part laser welding device and a welding method thereof, and relates to the technical field of steel structural part laser welding, the steel structural part laser welding device comprises an operation table and a machine base, the machine base is provided with a laser welding mechanism, the laser welding mechanism comprises a control set and a welding head, and the side, close to the welding head, of the laser welding mechanism is fixedly connected with a hanging bracket. The steel structural part laser welding device and the welding method thereof have the beneficial effects that in the steel structural part laser welding process, protective gas is introduced into the gas nozzle and then sprayed to the current laser welding position, weld joint protection is achieved, in the process, the recovery pump is started, and the gas nozzle is started; the recovery pump collects the protective gas escaping from the current laser welding position and guides the protective gas into the recovery frame, the protective gas extrudes the sealing plate and gradually escapes from the escaping holes in the lower portion to flow to the weld joint close to the current welding position, and therefore the effect that the just-solidified weld joint of the part is continuously protected, and the oxidation risk of the weld joint is reduced is achieved.

The invention discloses multifunctional threaded fastener welding equipment, and relates to the technical field of welding equipment.The multifunctional threaded fastener welding equipment comprises a bearing frame and a fixing frame, the fixing frame is arranged in front of the bearing frame, a mechanical arm is arranged at the top of the bearing frame, and a welding device is arranged at the top of the mechanical arm; a butt joint device and a clamping device are arranged on the left side of the fixing frame. The gas bottle is installed on the mechanical arm, the flow and pressure of gas are controlled through the pressure reducing valve, the current flow is checked through the flow meter, the gas is conveyed into the plasma arc welding gun through the pipeline, the gas is output from the output port of the plasma arc welding gun during welding, and a welding area can be prevented from making contact with oxygen through protective gas; therefore, oxidation and impurities are avoided, the welding quality is improved, when the gas cylinder is installed, an operator can replace the gas cylinder more quickly and more conveniently by quickly installing and disassembling the gas cylinder, and the shutdown time caused by replacement of the gas cylinder is avoided.

The invention discloses an intelligent robot for body-in-white welding, and relates to the technical field of welding robots, the intelligent robot comprises a base, a robot joint arm and a welding head, the robot joint arm is installed on the base, the welding head is installed at the end, away from the base, of the robot joint arm, and the upper end of the welding head fixedly communicates with a wire feeding pipe; the wire feeder is installed on the upper portion of the base, the end, away from the welding head, of the wire feeding pipe is installed on the wire feeder, the inner scraping ring and the outer scraping ring can clean the inner surface and the outer surface of the welding head, blockages such as splash welding slag generated by welding on the inner surface and the outer surface of a nozzle of the welding head can be scraped away, smooth circulation of protective gas is guaranteed, and a good welding environment is maintained. The conditions that if welding wire residues remain on the inner wall of the contact tube, friction can be increased in the follow-up welding wire conveying process, abrasion occurs, and the hole diameter becomes large are avoided, impurities prone to abrasion can be removed in time through cleaning, components can be kept in a good initial state, and the normal service life of a welding head is prolonged.

The invention provides a welding tool for an automobile rear auxiliary frame cross beam, and belongs to the technical field of automobile cross beam welding, the welding tool comprises a base, a rear auxiliary frame main body, an operation table and a welding robot, and the operation table and the welding robot are arranged on the base, and the welding tool further comprises a positioning splicing assembly and a flow guide destressing assembly; protective gas is integrated on the third clamping jaw, the third clamping jaw can effectively guide protective gas flow to a welding seam while fixing the side cross beam, and effective flow guide of the protective gas can be achieved in cooperation with arrangement of the movable spraying pipe; during welding, the impeller is static to block gas, the flow speed is reduced, welding fluid is prevented from splashing and losing due to overlarge airflow impact, and stable combustion of welding arcs is maintained; in the cooling stage after welding is completed, the inductor controls the electromagnetic base to be powered off, gas flow is increased, the cooling speed is increased, meanwhile, vibration is generated to be matched with cooling to eliminate welding residual stress, the stability and reliability of a weldment are improved, the production period can be shortened, and the production efficiency is improved.

The invention belongs to the technical field of welding, and discloses a dissimilar metal power modulation galvanometer laser welding method which comprises the following steps: finely cleaning a 6061 aluminum alloy and a 304 stainless steel plate by using acetone, and then airing for more than 20 minutes; the aluminum steel sheet is assembled, pressed and fixed on a welding test platform in a steel-up-aluminum-down mode; the position of the welding test platform is adjusted, argon serves as welding protection gas, and a protection gas nozzle is arranged to be aligned with a welding pool area; laser welding parameters are set, a laser power modulation mode is set to be a gradient power mode, and the gradient power mode is to regulate and control phase point laser power in a circular scanning track in the advancing direction of a welding seam; a welding test is carried out in the mode that a galvanometer laser head is fixed and a welding test platform is moved, and a laser and the welding test platform are synchronously started and stopped; and the protective gas is started 5 seconds before the laser is started, and after the laser is stopped, the protective gas is stopped lagging for 10 seconds so as to continuously protect the welding seam and prevent oxidation.

The invention discloses an intelligent argon arc welding machine based on case machining and a welding method, and relates to the technical field of case machining, the intelligent argon arc welding machine comprises a control box and a welding clamp, and further comprises a welding gun, the welding gun is composed of a grab handle and a welding head, and the welding head is fixedly connected with the grab handle through a butt joint sleeve; the welding head is composed of a welding part and an air injection part, and the welding part comprises a first welding pipe and a second welding pipe. The device has the advantages that when plates are welded, the conveying flow of the protector can be automatically changed according to the inclination angle of the welding gun, so that the protector is conveyed at the optimal flow, the protection effect of the protector is improved, the loss of shielding gas is reduced, meanwhile, the spraying speed of the shielding gas can be kept constant in the shielding gas changing process, and the probability of bubble generation is reduced; in addition, when the shielding gas is jetted, the protector is made to be perpendicular to the welding position all the time, and the protection effect of the shielding gas can be improved.

The invention provides an anti-wind device for gas shielded welding and a welding system. The anti-wind device for gas shielded welding comprises a tube shell, the tube shell is arranged outside a gun head of a welding gun in a sleeving mode, and a shielding gas containing cavity surrounding the gun head is formed between the tube shell and the gun head; the casing pipe is arranged outside the pipe shell in a sleeving mode, and an airflow drainage cavity surrounding the outside of the pipe shell is formed between the casing pipe and the pipe shell; the air source connector is arranged on the sleeve and communicated with the airflow drainage cavity, and the air source connector is used for guiding airflow from an air source into the airflow drainage cavity; the airflow drainage cavity is used for guiding airflow in the axial direction of the gun head so that the airflow can form an air curtain on the periphery of the shielding gas containing cavity. The anti-wind device can achieve the anti-wind function on the shielding gas, and compared with the prior art, the construction difficulty can be reduced, the equipment resource configuration can be simplified, and the construction cost can be saved.

The present invention relates to a flexible full-protection device for a weld seam, and a welding method. The device comprises: a protective cover, a first shielding gas pipe and a partition plate, wherein openings are respectively formed in the lower portion and the front end of the protective cover; the partition plate is located in the protective cover and fixed to the protective cover; the partition plate divides the interior of the protective cover into an upper cavity and a lower cavity; the protective cover and the partition plate are extendable / retractable; and an air outlet of the first shielding gas pipe is located in the lower cavity. According to the present invention, compressed air enters the upper cavity after being blown below a protective lens and flows into the upper cavity to generate negative pressure, so as to suction high-temperature welding fume into the upper cavity and move the welding fume away from the position above a welding point, reducing the adverse effects of the welding fume on the weld seam and preventing the welding fume from blocking laser light emitted by a laser head.

The invention relates to the field of welding devices, and discloses a laser swing welding device and a welding method.The laser swing welding device comprises a supporting table, an adjusting mechanism, a swing mechanism, a laser welding head, a gradient temperature changing mechanism, a housing, an air supply mechanism, an air injection preheating mechanism and a clamping mechanism; the adjusting mechanism is arranged on the supporting table and connected with the gradient temperature changing mechanism so as to change the welding position of the laser welding head. A first plate body and a second plate body are placed on the supporting table so as to be limited by the clamping mechanism. The laser welding head is rotationally arranged on the housing and driven by the swing mechanism so as to conduct swing welding on the welding position between the first plate body and the second plate body. Through cooperation of the gradient temperature changing mechanism, the ultrasonic transducer and the gas supply and jet preheating mechanism and cooperation of the eccentric driving disc and the swing frame, preheating of protective gas, gradient cooling after welding and heating are achieved, thermal stress and thermal shock are reduced, the welding seam performance is improved, laser energy is evenly distributed, and the welding quality of dissimilar metal plates is improved.

The invention belongs to the technical field of metal additive manufacturing, and relates to a preparation method of a large-size thin-wall structure based on magnetic field regulation and control of laser directional energy deposition. According to the method, the part forming area is filled with the protective gas, the oxygen content of the forming area is 100 ppm or below, and oxidation and inclusion pollution of alloy in the forming process are avoided. By starting the electromagnetic field generator, a stable uniform magnetic field is formed in a part forming area, the metallurgical behavior of a molten pool is regulated and controlled through the thermal damping effect and the thermal electromagnetic convection effect generated by the magnetic field in the molten pool, and optimization of the grain structure is achieved. A laser cladding head is started, powder metal materials are conveyed to the position of a molten pool through powder carrying gas, and the powder metal materials are molten through laser to form a stable molten pool; and a laser cladding head is controlled to scan in a uniform magnetic field area according to a set track to carry out circulating deposition, and light stopping is carried out every time deposition of one layer is completed, so that heat of a deposition layer is released, and heat accumulation is reduced until part forming is completed.

The invention relates to the technical field of welding assistance, in particular to an auxiliary device for metal pipe welding, which comprises a welding machining table, a sliding groove is formed in the welding machining table, and a first moving frame and a second moving frame are arranged in the sliding groove in a sliding manner; the first moving frame and the second moving frame are each provided with a first through groove allowing a metal pipe to penetrate through, and the first moving frame and the second moving frame are each provided with a sealing mechanism used for sealing the corresponding first through groove. According to the auxiliary device for metal pipe welding, by starting air cylinders on a first fixing frame and a second fixing frame, a laser welding machine is located over a welding seam, and as two second moving frames drive a second annular frame to be attached to the surface of a rotating ring, multiple sealing rings can abut against one another, the welding seam is made to be in a relatively-sealed environment, and the welding seam is welded. At the moment, the welding seam can be located in the space filled with the protective gas without dead angles by introducing the protective gas.

The present invention provides a handheld laser welding device, belonging to the technical field of laser welding, which is used to solve the problem that in the prior art, the integration of the welding torch and the interface greatly reduces the interchangeability between the welding torch and different laser hosts, restricting the versatility and flexibility of the equipment. The present invention provides a handheld laser welding device, comprising a welding torch head and an output interface that are inserted into each other in a matching manner. The other end of the welding torch head is used for welding, and the other end of the output interface is used for connecting to the host through a wire harness; the insertion interface between the welding torch head and the output interface includes: a laser matching group, a cooling matching group, a shielding gas matching group, and an electrical signal matching group. By optimizing the connection method between the handheld welding torch and the laser host and designing a standardized quick plug-and-play connection interface, both the high reliability of the connection and the high interchangeability of the welding torch are achieved.

The utility model discloses a laser welding device with a shielding gas heating function, which comprises a laser welding module, a shielding gas heating module is arranged on one side of the laser welding module, the shielding gas heating module comprises a cavity, the cavity is provided with a gas inlet and a gas outlet, a heating rod is arranged in the cavity, and the shielding gas heating module is arranged in the cavity. The air outlet is connected with an air supply pipe, and an outlet of the air supply pipe is arranged below a laser vibration mirror of the laser welding module. According to the utility model, nitrogen reaching a working procedure can be heated in advance, so that the consistency of the temperature of protective gas is ensured; and meanwhile, the shielding gas heating device has a temperature adjustable and controllable function, and the optimal temperature of the shielding gas can be confirmed by discussing the influence of the shielding gas at different temperatures on gas holes and cracks after welding, so that the cooling speed after welding is slowed down, the gas escapes from a molten pool, the probability of generating the welding cracks and the gas holes is reduced, and the welding quality is improved.

The invention provides a production process for stably controlling adhesive force of a DP steel zinc layer. The production process comprises the following steps: step 1, setting a heating section 1, a heating section 2 and a furnace nose section in a total radiation heating annealing furnace; 2, according to the model and thickness of DP steel, target dew points of a first heating section, a second heating section and a furnace nose section are set; 3, according to the target dew points set in the first heating section, the second heating section and the furnace nose section in the step 2, water vapor is put into the protective gas for humidification, and the water vapor reacts with Si, Mn and Cr elements enriched on the surface of the steel plate to generate volatile oxides; the dew point of the annealing furnace is precisely controlled in a segmented mode, different humidification modes are adopted, and the surface state is controlled, so that surface oxide residues are reduced, cleanliness of a steel substrate is guaranteed, and the binding force of a zinc layer is improved; the iron oxide layer formed on the surface of the steel plate enters a reducing atmosphere annealing furnace containing hydrogen, the hydrogen can reduce the iron oxide layer on the surface of the steel plate to form a reduced iron layer, and the adhesive force of a zinc layer is improved.

The invention belongs to the technical field of welding, and provides a laser welding tool and method for a thin-wall titanium alloy runner plate. A small-diameter welding wire is adopted, the laser power is adjusted, protective gas purging is started, and laser welding is conducted in the anticlockwise direction from the left lower portion; in the welding process, active cooling is carried out at the same time until welding is completed; after welding is completed, the fixing module is detached; the active cooling specifically comprises the steps that absolute ethyl alcohol is sprayed on the welded surface, after absolute ethyl alcohol on the surface of the cold plate (3) to be welded volatilizes completely and ventilation is kept for 2 min, protective gas is started again for purging for 10 s, and one-time active cooling is completed. The method is used for solving the problem that a laser welding method in the prior art easily causes heat accumulation deformation of the titanium alloy sheet, so that the welding precision of the sheet is ensured.

The utility model discloses a press fitting assembly and a welding device. The press-fitting assembly comprises a base and a welding protection disc. The base is used for placing a battery cell, the welding protection disc is used for pressing the current collecting disc on the top of the battery cell, and the welding protection disc is provided with a first flow channel, a second flow channel and a laser channel. The laser channel is used for allowing laser to enter and irradiate the flow collecting disc. An air outlet of the first flow channel is a first air outlet, and the first air outlet is located in the inner wall face of the laser channel. An air inlet of the second flow channel is a second air inlet, an air outlet of the second flow channel is a second air outlet, the second air inlet is located in the inner wall face of the laser channel, and the second air outlet is used for being connected with first air extraction equipment. According to the welding protection disc, air enters from the laser channel penetrating through the welding protection disc, the first air outlet is formed in the inner wall face of the laser channel, protection gas directly falls on the flow collecting disc for protection after coming out of the first air outlet, interference between the protection gas and the air is reduced through the arrangement, and the welding quality is improved.

To provide a metal laminate molding device capable of stabilizing a build-up height and a molding shape by keeping a molten pool and shield gas at a constant state.SOLUTION: A metal laminate molding device 10 forms a three-dimensional molding object 7 by feeding a wire 42 via a wire nozzle 41 to perform build-up welding while irradiating the molding object 7 with a laser beam from an irradiation head 21. A wire nozzle rotation drive unit 54 rotates the wire nozzle 41 around a central axis 23 of the irradiation head 21.SELECTED DRAWING: Figure 1

The invention provides a robot welding machine, and belongs to the technical field of welding robots, the robot welding machine comprises a robot body, and further comprises a shunting heat conduction assembly and a supporting cleaning assembly; protective gas forms focused gas flow through shunting and secondary shunting, and gas flow sprayed by the cooling channel and the permeable plate is uniformly mixed under the guidance of a conical space at the front end of the nozzle, so that the concentration distribution of the protective gas above a molten pool is consistent, and the welding seam quality is improved; trace moisture in the protective gas is treated under the action of centrifugal force of the turbofan, and water vapor generated by falling and evaporation of water drops is guided to the periphery of the gas hood and cannot intrude into a molten pool area; the heat conduction cylinder rotates to enable airflow to sweep the whole surface of the contact tube, local overheating and heat dissipation dead angles are avoided, and the normal working temperature of the contact tube is guaranteed; the airflow can clean splashing particles attached to the outer side of the contact tube and the inner wall of the nozzle, the scraping arm can be tightly attached to the cleaning face in the rotating process and can abut against the contact tube, the deformation possibility of the contact tube is reduced, and the continuity and stability of the welding process are guaranteed.

The invention relates to the technical field of building construction welding, in particular to steel structure electric arc welding equipment for building construction. The device comprises a welding gun, a nozzle structure is installed at the bottom of a welding head connecting pipe in a threaded mode, the nozzle structure comprises a hollow spraying pipe and a contact tube extending from the interior of the welding head connecting pipe, an isolation inner pipe is installed in the spraying pipe in a clamped mode, and a gas flow channel formed between the spraying pipe and the contact tube is separated through the isolation inner pipe. The external expansion structure at the lower end of the isolation inner pipe is matched with the height difference between the bottom end of the isolation inner pipe and the bottom end of the spray pipe, physical shielding is formed, and high-temperature splashes entering the external sub-runner during welding are reduced; therefore, adhesion on the inner wall of the outer sub-runner is effectively avoided, the outer sub-runner is kept smooth all the time, and stable conveying of the protective gas is guaranteed.

The invention provides a stainless steel ultra-thick plate laser welding method and device, and the method comprises the steps that a to-be-welded end face of ultra-thick stainless steel is subjected to groove machining, the groove form is a combined form of a large truncated edge and a U-shaped groove, with the groove as a boundary, one end is a first base material, and the other end is a second base material; placing the workpiece according to a corresponding welding method, tightly butting the first base metal and the second base metal, fixing by using a clamp, and then cleaning a to-be-welded surface; the relative positions of the laser beam and the protective gas hood and the base metal are adjusted according to parameters required by the process, and a welding path is programmed or demonstrated; setting welding process parameters; and opening a protective gas valve, starting welding after the welding area is filled with protective gas, and performing front welding, back welding or front and back cover welding. The method can be used for penetration welding of stainless steel super-thick plates or backing welding of deep-groove and thick-truncated-edge super-thick plates, the welding efficiency can be remarkably improved, welding deformation is reduced, and the post-welding machining allowance of high-precision products is reduced.

The utility model relates to the technical field of pressing tools, in particular to a copper nozzle pressing tool which comprises a pressing tool body and a copper nozzle, a positioning seat is arranged on the pressing tool body, a copper nozzle positioning hole is formed in the positioning seat, connecting holes are further formed in the positioning seat at intervals, the copper nozzle positioning hole is matched with the copper nozzle in a clamped mode, and the copper nozzle positioning hole is matched with the copper nozzle in a clamped mode. A copper nozzle positioning hole is formed in the positioning seat, a gas circulation gap is further formed between the copper nozzle positioning hole and the copper nozzle, a dust suction channel and a protective gas channel are formed in the two opposite sides of the positioning seat correspondingly and are both obliquely arranged, and a protective gas inlet is formed between the protective gas channel and the gas circulation gap. A dust extraction opening is formed between the dust extraction channel and the gas circulation gap, and the protective gas inlet is lower than the dust extraction opening. According to the copper nozzle pressing tool, the mode that dust is directly extracted from the side face is adopted, it is guaranteed that the welding environment is free of impurities, black holes and explosion holes, an outlet of shielding gas is lower than a dust extraction opening, and the welding protection performance is guaranteed.

The invention discloses a laser welding method for dual-phase steel and aluminum alloy with a preset nanometer rare earth middle layer, and belongs to the field of dissimilar material laser welding. The laser welding method comprises the steps that to-be-welded parts of an aluminum alloy plate and a dual-phase steel plate are subjected to accurate grinding and cleaning; the preparation method comprises the following steps: uniformly mixing aluminum powder with nanoscale CeO2 powder, and adding acetone to obtain pasty Al-CeO2 powder; a groove is cut in the side, making contact with the dual-phase steel plate, of the aluminum alloy plate in the welding seam direction, and the groove is pre-coated with the pasty Al-CeO2 powder; a protective gas device is installed, and argon is used for welding protection; and fifthly, the aluminum alloy and dual-phase steel plate welding test piece is clamped to a universal welding clamp, and laser welding is conducted. According to the method, the problem that cracks are generated on the bonding surface in steel-aluminum welding and the problem that air holes are generated when rare earth oxide is added in steel-aluminum welding are solved, the size and the number of brittle intermetallic compounds at the interface are reduced, and the loading capacity of a steel-aluminum laser welding joint is improved.

The present invention provides a local dry underwater laser welding multi-shielding gas filler wire drainage device, comprising an adjustable straight pipe, a connecting module, a drainage cover, a nozzle, and a wire feeding pipe. The connecting module is provided with a welding shielding gas inlet hole; the connecting module, the adjustable straight pipe, and the nozzle are sequentially connected from top to bottom and jointly form a long straight through path; the welding shielding gas inlet hole is communicated with the long straight through path; the drainage cover is sleeved on the outer side of the adjustable straight pipe to form a drainage cavity having a downward opening; the drainage cover is provided with a drainage gas inlet hole, and the drainage gas inlet hole is communicated with the drainage cavity; a fixing channel is formed on one side of the drainage cover; the wire feeding pipe extends into the drainage cavity from the fixing channel; a third gap is formed between the inner wall of the fixing channel and the outer side of the wire feeding pipe; a welding wire shielding gas inlet hole is formed in the wall of the fixing channel; the welding wire shielding gas inlet hole is communicated with the drainage cavity by means of the third gap. The drainage device can satisfy the requirement of underwater filler wire laser welding, and relates to innovative use of welding wire shielding gas to ensure that welding wires are in a dry state, thereby effectively improving the quality of filler wire welding.

The invention relates to the technical field of silicon nitride material preparation, and in particular to a high thermal conductivity silicon nitride substrate debinding process. The invention comprises the following steps: firstly performing gradient heating debinding after vacuuming a debinding furnace, then charging a protective gas into the debinding furnace to make the pressure in the furnace reach 0.07-0.1Mpa, then sequentially performing ultra-high temperature treatment and temperature control and cooling treatment, and finally cooling the furnace to room temperature to obtain a silicon nitride green sheet; the gradient heating debinding comprises firstly heating the temperature to 150-200°C at 1-3°C / min and keeping the temperature for 0.5-1h, then heating the temperature to 300-350°C / min at 1-3°C / min and keeping the temperature for 1-2h, and finally heating the temperature to 550-600°C at 2-5°C / min and keeping the temperature for 1-2h; the ultra-high temperature treatment comprises heating the temperature to 1100-1150°C at 4-6°C / min and keeping the temperature for 2-6h; and the temperature control and cooling treatment comprises cooling the temperature to 150-200°C at 2-5°C / min. The present invention reduces the carbon atomic percentage of the silicon nitride green sheet to the greatest extent through the debinding process, thereby further improving the thermal conductivity of the silicon nitride substrate.

The invention discloses a gas saving device for welding shielding gas, and relates to the technical field of shielding gas saving, the gas saving device comprises gas saving equipment, a fluid pipeline and a control part are arranged in the gas saving equipment, the control part drives a baffle in the fluid pipeline to move through obtained seam width data so as to obtain the maximum flow of welding the seam width; according to the method, the maximum fluid flow during welding of the seam width is determined through the seam width, namely, targeted fluid flow adjustment can be conducted according to different welding seam widths, the purpose of preliminary gas saving is achieved, and meanwhile covering of protective gas can be guaranteed. And the rotating angle of the dynamic adjusting plate is adjusted according to the proportion, so that the flow is dynamically adjusted to further save gas. According to the real-time change of the welding current, the gas flow is intelligently controlled, and gas is supplied after being specially treated on the premise that the gas formula is not changed. And the gas consumption is effectively reduced while the welding quality is ensured.

The invention provides a solid-core welding wire and a welding method for high-strength weathering steel for a 500MPa-grade railway bridge by adopting the solid-core welding wire. The solid welding wire comprises the following chemical components in percentage by mass: 0.02%-0.08% of C, 1.10%-1.60% of Mn, 0.18%-0.60% of Si, less than or equal to 0.01% of P, less than or equal to 0.005% of S, 0.40%-0.60% of Cr, 0.30%-0.60% of Ni, 0.30%-0.45% of Cu, 0.05%-0.20% of Mo, less than or equal to 0.05% of V and the balance of Fe and inevitable impurities. According to the welding method, welding parameters are set as follows: the welding voltage is 26-30 V, the welding current is 260-300 A, the welding speed is 30-40 cm / min, the welding heat input is 12-15 kJ / cm, and the protective gas flow is 15-20 L / min; and after each welding seam is completed, the next welding seam is welded when the temperature of the welding seam is less than or equal to 150 DEG C.

The invention provides a coal mine hydraulic support gas shield welding wire with the strength higher than 900 MPa and a preparation method of the coal mine hydraulic support gas shield welding wire. The gas shield welding wire comprises, by mass, 0.03%-0.06% of C, 0.51%-0.70% of Si, 1.35%-1.64% of Mn, smaller than or equal to 0.010% of P, smaller than or equal to 0.005% of S, 0.20%-0.38% of Cr, 2.35%-2.65% of Ni, 0%-0.09% of Cu, 0.45%-0.70% of Mo, 0.015%-0.030% of Ti, 0.025%-0.035% of Nb, 0.002%-0.006% of Ce, 0.0005%-0.0012% of B, smaller than or equal to 0.004% of O, smaller than or equal to 0.006% of N and the balance Fe and The invention has the following beneficial effects: (1) through reasonable design of chemical components, the yield strength of weld metal is greater than or equal to 820 MPa, the tensile strength is greater than or equal to 900 MPa, the ductility is greater than or equal to 21%, and the low-temperature impact toughness at-40 DEG C is greater than or equal to 75 J; (2) inclusions in a weld joint are dispersed and refined after the welding wire is welded, refined acicular ferrite instead of bainite and martensite is taken as a main structure, and the strength and toughness of the weld joint are excellent; and (3) the composition proportion of the welding wire is optimized, a stable welding wire preparation process is developed according to the components, and the comprehensive performance of the high-strength coal mine hydraulic support welding seam is considered.

The invention belongs to the technical field of metal preparation, and particularly relates to a Fe-Al-Nb alloy and a preparation method thereof. Comprising the following steps: mixing ferric oxide, niobium pentoxide powder and a metal diluent, performing ball milling, and pressing into a green body; and the blank is put into a reaction kettle, then an ignition agent is added, protective gas is inflated, a self-propagating reaction is conducted at the temperature of 260-300 DEG C, and the Fe-Al-Nb alloy is obtained. The Fe-Al-Nb alloy is prepared through the self-propagating reaction, the reaction temperature is reduced, the thermal stress during forming is improved, the temperature of the self-propagating reaction is only 260-300 DEG C, meanwhile, the self-propagating reaction mode is adopted, the alloy is rapidly cooled after reacting, the fine grain strengthening effect is promoted to be more obvious, a microstructure of a Fe3Al matrix phase and a C14 Laves reinforced phase is formed, and the Fe-Al-Nb alloy is obtained. And the distribution of a reinforced phase is more uniform, and the wear resistance of the material is improved.