680 results about "Gas protection" patented technology

The invention belongs to the technical field of laser welding, and discloses a multi-parameter cooperative control laser welding method and system.The method comprises the steps that a laser energy control model is established based on material strength-thickness-gap ternary coupling, and the output power of an optical fiber laser is controlled; coaxial three-layer gradient gas is adopted for protection of a welding area, preheating before welding and double-temperature-zone gradient annealing after welding are adopted, the output power of an optical fiber laser and the three-layer gradient gas protection flow are regulated and controlled in real time through combination of multiple sensors and a control algorithm, the temperature of a heat affected zone is monitored in real time, and a cooling nozzle is controlled for cooling. And continuous parameter optimization is achieved through machine learning, and multi-parameter control laser welding is achieved.

A copper-aluminum composite plate material prepared by aluminum liquid continuous casting and a process thereof. The method includes: S1, heating an aluminum ingot to 700-800° C. and smelting for 1-3 h; S2, degassing smelted aluminum liquid, and keeping the temperature and standing; S3, texturing a copper strip, and then cleaning; S4, heating the pretreated copper strip to 200-650° C.; S5, under the protection of inert gas, continuously casting the treated aluminum liquid on the treated copper strip, performing quenching crystallization on a copper-aluminum composite material, and performing oxygen-free continuous casting; and S6, continuous rolling: rolling the continuously cast copper-aluminum composite material to obtain the copper-aluminum composite plate material prepared by aluminum liquid continuous casting.

The invention discloses a welding method of a high-strength steel vertical rod for a ring lock type scaffold and the vertical rod. A target high-frequency welded pipe is selected as a vertical rod main body; the gap between the disc buckle and the high-frequency welded pipe is controlled to be 0.3 mm-0. 7 mm through a positioning device; according to a preset target welding process specification, gas shielded welding wires are adopted to conduct angle welding with low welding heat input on the two sides of the disc buckle, and the value of the low welding heat input ranges from 3.23 KJ / cm to 4.94 KJ / cm. Therefore, the high-strength light-weight vertical rod is used, and the vertical rod and the disc buckle are welded according to the target welding process specification, so that the safety of the high-strength steel scaffold vertical rod in use is ensured, the mounting efficiency of the vertical rod is improved, and the working intensity of constructors is reduced.

The invention provides a Q890qE and Q420qE bridge steel flat butt joint combined welding method which comprises the following steps: step 1, grinding and derusting grooves of upper and lower asymmetric double-sided V-shaped joints to expose metallic luster; 2, preheating is conducted in an electric heating mode; 3, a solid welding wire CO2 gas shielded welding is adopted for backing welding of one weld joint on the upper V-shaped deep groove side; 4, welding seams are filled in the side of the V-shaped deep groove through submerged arc automatic welding, and the filling thickness is about 1 / 2 of the groove depth; 5, back gouging is conducted on the back face through carbon arc air gouging, and a carburized layer is polished and cleaned till metallic luster is exposed; 6, the V-shaped shallow groove is welded and filled; seventhly, the submerged arc automatic welding continues to weld the remaining weld joints of the V-shaped deep groove till the remaining weld joints are filled; and 8, postweld heat treatment is conducted. According to the method, a combined welding method of solid welding wire CO2 gas shielded welding bottoming, submerged arc automatic welding filling and capping is adopted, the problems of welding cold cracking and early joint breakage of the dissimilar bridge steel are solved by combining joint design, and the mechanical properties of a welding seam and a fusion area meet the standard requirements.

The invention relates to an inner cavity curved surface welding line laser light path turning welding method which is used for solving the technical problem that an existing welding method is difficult to operate when curved surface welding is carried out in an inner cavity, and the method comprises the steps that a reflecting mirror is arranged on a light emitting path of a laser welding head, and original laser beams are deflected; the laser beam enters the inner cavity space and irradiates the to-be-welded area of the curved surface weld joint; surface cleaning and fixing are conducted on a to-be-welded area, and the folded laser beams are focused to the center of a welding seam; enabling the laser beam to perform scanning welding on the curved surface welding seam according to a preset scanning track; in the welding process, protective gas is jetted to the position, acting on the workpiece, of the laser beam so as to blow away welding spatter and provide gas protection for a welding seam. The propagation direction of laser beams is changed through the reflecting mirror, so that laser can enter the inner cavity to weld a curved surface weld joint, the application range of laser welding is expanded, and the problem that curved surface welding is difficult to operate in the inner cavity space through an existing welding method is solved.

The invention discloses a magnetic attraction synchronous walking type inert gas protection titanium alloy pipe welding robot which comprises a titanium alloy pipe to be welded, an active welding robot, a follow-up inert gas protection robot and a mechanical arm. After the two titanium alloy to-be-welded pipes are coaxially spliced, a circle of to-be-welded seam is formed at the splicing position; the active welding robot walks and is attached to the outer wall face of a titanium alloy to-be-welded pipe under connection of the mechanical arm, the follow-up inert gas protection robot walks and is attached to the inner wall of the titanium alloy to-be-welded pipe, and the follow-up inert gas protection robot and the active welding robot magnetically attract each other through a magnetic attraction device. The follow-up inert gas protection robot follows the active welding robot under the action of magnetic force; and no oxidation of a welding area is realized in an invisible pipeline by the equipment.

The invention relates to the technical field of welding equipment, and discloses steel product gas shielded welding equipment which comprises a machining table, a continuous automatic welding mechanism, a synchronous filtering and dust collecting mechanism and a flow adjusting mechanism. Side plates are vertically and fixedly arranged on the two sides of the top of the machining table, and a top plate is fixedly arranged on the tops of the side plates. According to the gas shielded welding equipment for the steel products, constant-speed automatic welding of the workpieces is achieved through the constant-speed automatic welding mechanism, and the situation that the welding quality is affected due to unstable connection of weld joints of welding rods and the workpieces due to the uneven welding speed is avoided; when the constant-speed automatic welding mechanism operates, the synchronous filtering and dust collecting mechanism is driven to collect and treat smoke generated during welding, air pollution caused by the smoke is avoided, and when the synchronous filtering and dust collecting mechanism operates, the flow adjusting mechanism is driven to automatically adjust the flow of protective gas. And instability of a protective dielectric layer formed by protective gas when the welding speed is different is avoided, so that the protective effect on the weld joint is improved.

The invention discloses a double-pulse gas shielded welding machine and a using method thereof, and relates to the technical field of double-pulse gas shielded welding machines, the double-pulse gas shielded welding machine comprises a welding machine main body, a mounting frame is fixedly arranged on the welding machine main body, a wire winding roll for winding a welding wire is arranged on the mounting frame, and a wire feeding unit is further mounted on the mounting frame; the wire feeding unit comprises a wire feeder body and a fixing pipe which are fixedly arranged on the mounting frame, a welding wire state detection mechanism is mounted on the inner side of the fixing pipe, and when a welding wire jumps in the radial direction, a pushing rod fixedly connected with a wheel seat can be pushed to slide relative to a top plate, and then a V-shaped swing rod is pushed to rotate around a second rotating shaft; the push rod drives the impact ball connected through the vibration spring to knock the copper sheet, the vibration spring is matched to improve the knocking frequency and the warning effect, abnormal jumping of the welding wire can be captured in the first time, the reset structure arranged on the outer side of the push rod in a sleeving mode can guarantee the stability of repeated use of the detection mechanism, and abrasion caused by radial jumping of the welding wire to an inner channel of a welding gun is effectively avoided.

The invention provides a vertical position welding method for bridge steel. The vertical position welding method comprises the steps that 1, a groove is manufactured, specifically, the X-shaped groove without a truncated edge is manufactured in a vertical position mode through a flame cutting technology; and the groove is polished and derusted according to requirements. 2, preheating, wherein the bridge steel is preheated to 75 DEG C in an electric heating mode; and 3, welding, wherein solid welding wire argon-rich mixed gas shielded welding is adopted for vertical position welding. And 4, post-weld heat treatment is conducted, specifically, after welding is completed, post-heat treatment is conducted at 200-250 DEG C through a crawler-type heater, and slow cooling is conducted to the room temperature after heat preservation is conducted for 3 hours. By researching and developing a welding material and a welding process matched with the Q890qE high-strength bridge steel, the technical problem of quality of a Q890qE vertical position butt welding seam is solved. Welding forming is stable, efficiency is high, deformation is small, the appearance is good, strength and weather resistance are balanced, the service life is long, and economical efficiency and environment friendliness are both considered; the method is especially suitable for engineering scenes with strict requirements on strength, toughness and durability such as long-span bridges and alpine region bridges, and has remarkable economic advantages and social value.

The utility model provides a CFB stokehole storage device. The CFB stokehole storage device comprises a stokehole bin, a main control system, an oxygen detector, a temperature detector and a gas protection assembly, wherein the oxygen detector and the temperature detector are arranged in the stokehole bin; wherein the oxygen detector is used for detecting a real-time oxygen content signal in the furnace front bin and sending the real-time oxygen content signal to the main control system; the temperature detector is used for detecting a real-time temperature signal in the furnace front bin and sending the real-time temperature signal to the main control system; the main control system is used for controlling the gas protection assembly to input protection gas into the furnace front bin according to the real-time oxygen content signal and the real-time temperature signal. According to the utility model, multi-index automatic monitoring can be carried out on the stokehole bin in real time, and the stokehole bin can be protected in time through the protective gas under the condition that safety risks exist, so that the safety and reliability of stored articles are ensured.

The invention provides a welding device for power plant boiler installation, and belongs to the technical field of boiler installation and welding. Comprising a welding installation part, a knocking auxiliary part is installed on the welding installation part, the knocking auxiliary part is used for preventing the welding installation part from being damaged, an attaching installation part is installed on the welding installation part, a gas facing protection part is installed on the attaching installation part, and the gas facing protection part is used for ensuring the gas protection quality. A swing limiting piece is installed on the attaching installation piece and used for improving operation standardability, and a gas protection prompting piece is installed on the welding installation piece. The gas facing protection part is arranged to be matched with the attaching installation part to be used for limiting the operation standardization of workers, and the carbon dioxide protection quality is guaranteed; the problems that an existing welding device for installing the boiler of the power plant is inconvenient to automatically control and limit gas-facing welding of workers, and welding wires for carbon dioxide protection welding are also prone to being blocked by splashing objects are solved.

The invention relates to the technical field of powder material processing, and discloses an inert gas protected micro-powder impact mill system which comprises a crushing and grading module, an inert gas circulating module, a material closed conveying module and a safety monitoring and regulating module, the crushing and grading module comprises an impact mill and a worm gear grader, and a bottom discharge port of the impact mill is communicated with a top feed port of the worm gear grader through a sealing pipeline; the inert gas circulation module comprises a gas storage tank, an induced draft fan, a pulse type bag-type dust collector and a return air cooler, a gas outlet of the gas storage tank is in sealed connection with a gas inlet of the induced draft fan through a first communicating pipe with a control valve, and a gas outlet of the induced draft fan is communicated with a gas inlet of the impact mill through a second communicating pipe. By constructing a complete inert gas closed circulation loop and combining with a safety monitoring regulation and control module of the integrated control system, potential safety hazards caused when flammable, explosive and oxidizable materials are processed by an existing common impact mill are effectively solved.

The utility model discloses a movable tubular pile gas shielded welding windshield which comprises a radius adjusting cover and a perimeter adjusting block, the radius adjusting cover is of an arc-shaped structure, the inner ring of the radius adjusting cover is attached and adsorbed to the circumferential outer wall of a tubular pile, and the outer ring of the radius adjusting cover is symmetrical and is connected with a welding gun rod in an elastic tensioning mode. Perimeter adjusting blocks are telescopically inserted into two circumferential end surfaces of the arc-shaped structure of the radius adjusting cover. The windproof cover is used for covering and protecting the flame of the welding gun, can adaptively adjust the local covering radius and arc length according to the diameter of a pipe pile, can move along with the movement of the welding gun, and is simple in structure and easy to implement.

The utility model relates to the technical field of welding machines, and discloses a gas shielded welding machine for corner bracket production, which comprises a movable seat, a welding machine main body is arranged at the top of the movable seat, and an adjustable push handle positioned on the left side of the welding machine main body is arranged at the top of the movable seat. A welding gun pipeline assembly located on the right side of the welding machine body and connected with the welding machine body is arranged at the top of the movable base. According to the gas shielded welding machine for corner bracket production, by arranging a welding gun pipeline assembly and a protection assembly, firstly, a threaded rod is rotated to drive a protection frame to move upwards, so that a winding roller is opened, a worker can wind a pipeline outside the winding roller at the moment, and the welding gun pipeline is clamped in a U-shaped clamping seat at the moment; and at the moment, a fastening bolt is screwed off to fasten and limit the welding gun pipeline, then the purpose of winding and unwinding the pipeline can be achieved, then a threaded rod is rotated to drive a protection frame to move downwards to protect the pipeline, the practicability of the device is improved, and the device is convenient to use by workers.

The invention provides a method for manufacturing a copper-aluminum composite pipe, which comprises the following steps of: preheating a copper pipe to 600-620 DEG C, and conveying the copper pipe to a graphite mold filled with inert gas; the medium-frequency aluminum melting furnace heats an aluminum raw material to 700-730 DEG C, the aluminum raw material is injected into the copper pipe in the graphite mold, the aluminum solution wraps the outer surface of the copper pipe, and then the cast copper pipe is pulled out of the graphite mold. And a cooling mechanism is used for cooling twice, and the copper-aluminum composite pipe is obtained. By preheating the copper pipe and cooperating with inert gas protection, temperature difference impact and oxidation interference are reduced, and it is guaranteed that molten aluminum is evenly spread; molten aluminum is heated, silicon is added, the liquidity and wettability of the molten aluminum are improved, and CuAl2 brittle phase nucleation is inhibited; a layered cooling mechanism is matched to precisely regulate and control the temperature gradient, and local stress concentration is avoided; and finally, through cooperative control of technological parameters and a dynamic model, the copper-aluminum interface bonding strength and the plasticity of the composite pipe are improved, the interface defect problem is solved, and the copper-aluminum composite pipe with high reliability and long service life is obtained.

The invention discloses a rolled plate welding process for a steel tower drum, and relates to the technical field of wind power tower drum rolled plate welding processes, and the process comprises the steps of steel plate pretreatment, intelligent plate rolling, gradient groove processing, segmented temperature control welding, pulse stress relief treatment and the like. The surface of a steel plate is cleaned by adopting a laser cleaning technology, the quality of the steel plate is ensured by combining eddy current detection and the like, the radian deviation of the intelligent rolled plate is corrected in real time through a plate rolling machine with an automatic aligning function and three-dimensional scanning, a composite structure of a 45-degree main groove and a 15-degree auxiliary groove is formed through gradient groove processing, and the size of a truncated edge is adaptively adjusted; the sectional temperature control welding adopts double-wire gas metal arc welding, temperature, current and voltage are controlled in a preheating section, a penetration section and a slow cooling section, residual stress is quickly released through pulse current in pulse stress relief treatment, and the process effectively solves the problems of large welding deformation, low welding efficiency, long stress relief treatment time and the like in large-scale tower drum manufacturing. And the welding quality and the production efficiency are both improved.

The application provides an austenitic welding wire suitable for high-strength steel structure and a welding method, and belongs to the technical field of welding.The application adopts a multi-element protective gas, wherein the multi-element protective gas comprises Ar 43-50%, He 43-50%, N2 2-7% and O2 0-2% in terms of volume content, and Ar+He is greater than or equal to 93%; wherein Ar can effectively isolate air, He can shrink the electric arc, improve the electric arc temperature, N2 can improve the electric arc stiffness, supplement the N element loss of the weld, ensure the strength and toughness of the weld, and O2 can improve the electric arc stability. The multi-element protective gas can improve the forming condition of the austenitic welding material in the gas shielded arc welding, reduce welding defects and improve the strength and toughness of the weld by mixing in different proportions. The application can improve the proportion and size of the strengthening phase by controlling the composition of the welding wire, and further improve the strength and toughness of the weld.

The invention relates to the technical field of filling devices, and discloses an oral liquid filling auxiliary device capable of eliminating discharging bubbles, which comprises a frame body, a feeding and discharging station, a filling station, an exhaust station and an inert gas injection station are sequentially arranged on the frame body in the clockwise direction, and a directional transmission system is mounted on the frame body. The directional transmission system is connected with a rotatable station rotating frame, the station rotating frame is provided with four centrifugal and oscillation bubble removing systems, each centrifugal and oscillation bubble removing system is connected with a rotating tray capable of synchronously rotating and vertically vibrating in a reciprocating mode at a non-feeding and non-discharging station, and an inner cylinder is fixedly installed at the top of the frame body. Through innovative designs such as multi-physical-field collaborative bubble removal, intelligent regulation and control of exhaust, inert gas protection and high-precision transmission, the core problems of bubble residues, oxidation risks, low efficiency and poor stability of a traditional filling device are systematically solved, and remarkable breakthrough is achieved in the technical effect and the economic benefit.

A gas protection system, a gas protection method, and an energy storage system are provided. The gas protection system includes: a gas transmission pipe in communication with a sealed cabinet, where the gas transmission pipe is configured to input and output a protective gas to and from the sealed cabinet; a first detection module disposed in the gas transmission pipe; and a gas supply module configured to acquire gas parameters of the protective gas in the gas transmission pipe from the first detection module and supply a gas to the sealed cabinet based on the gas parameters.

The invention provides a grain storage process of an airtight heat insulation type green grain storage container, and relates to the technical field of grain storage, the grain storage process comprises the following steps: S1, arranging an air film bin; the cover body is opened, the air film bin is laid in the box body, the grains are placed in the air film bin, and after the grains are placed, the air film bin is controlled to be closed; and S2, gas protection structure arrangement is conducted, specifically, the multiple airtight protection assemblies sequentially penetrate through the installation panel from one side, the airtight protection assemblies slide to the preset positions, and the airtight protection assemblies and the installation panel are controlled to be in a mutually-engaged sliding state. The air bags do not need to be pumped during preliminary installation, installation and arrangement of workers are facilitated, after the multiple airtight protection assemblies are arranged, the expanded air bags abut against one another to push the air bags and the positioning plates on the inner sides to slide to the preset positions, finally, a compact gas protection face is formed, simplicity and convenience are achieved, the overall arrangement time is shortened, and the working efficiency is improved. And the overall arrangement difficulty is greatly reduced.

The utility model discloses a gas shield automatic welding device for welding a cladding layer of a composite plate. The device comprises a crawling welding robot which comprises a box body and a box body base, and the box body base is fixed to the bottom of the box body through welding; the crawling welding robot is installed on the walking soft rail and can walk through walking tooth holes in the walking soft rail; one end of the first main body rotating connecting piece is fixed to the box base; a second body rotation link having one end connected to the other end of the first body rotation link; the plurality of magnets are arranged below the walking soft rail; a longitudinal adjusting block and a transverse adjusting block, the other end of the second main body rotation connecting piece is fixed to the longitudinal adjusting block, and the longitudinal adjusting block and the transverse adjusting block are connected together; and the gas shielded welding gun head is fixed to the transverse adjusting block. The device improves the welding efficiency and improves the quality of the inner surface and the outer surface of a welding seam.

This utility model relates to the field of titanium alloy welding and discloses an auxiliary device for gas protection in titanium alloy MIG welding. The device includes a cover, with auxiliary plates on both the left and right sides of the bottom surface of the cover, rubber components on both sides of the cover, a mounting ring fixedly connected to the top of the cover, and a gas supply assembly on the upper part of the cover. Multiple ball bearings are rotatably connected to the bottom of the auxiliary plates, and a mounting groove is formed in the middle of the auxiliary plates. A mounting plate is fixedly connected to the bottom surface of the cover, and the mounting plate is movably connected to the mounting groove. Multiple bolts are threadedly connected between the mounting plate and the mounting groove. In this utility model, the interaction between the cover, auxiliary plates, ball bearings, and other components effectively reduces friction during cover movement. Furthermore, the interaction between the mounting plate, mounting opening, and bolts makes the auxiliary plate easier to replace and more practical.

This invention relates to a double-sided welding process for U-rib plates used in the construction of orthogonal steel structure bridges or the reinforcement of dangerous bridges. The process includes: welding the inner weld of the U-rib plate in the patch section using a small, dedicated U-rib welding robot via gas metal arc welding (GMAW); removing the welding wire feeder and the GMAW robot from the opening of the next adjacent patch section; cleaning the root of the outer weld of the patch section; welding the outer joint of the U-rib plate using GMAW; and using ultrasonic impact to impact the outer weld of the patch section to reduce welding tensile stress. This invention addresses the problem of double-sided welding of the inner and outer joints of the U-rib patch section in orthogonal steel structure bridges, offering both economic and social benefits.

The invention discloses a high-temperature alloy turbine blade directional solidification method based on multistage dynamic gas protection control. The high-temperature alloy turbine blade directional solidification method comprises the following steps that a high-temperature alloy mother alloy material is put into a crucible; filling inert gas to a preset pressure, heating the crucible, heating to a preset temperature, and keeping the temperature to ensure that the alloy liquid is liquefied; continuously filling inert gas to preset pressure and then refining, wherein a vibration generator generates a magnetic field in the refining process to carry out electromagnetic vibration on the alloy liquid; continuously filling inert gas to preset pressure, and then transferring the crucible; inert gas is continuously filled to preset pressure, then the crucible is tilted, pouring is conducted, and in the pouring process, a gas purging device sprays the inert gas to conduct purging protection on the alloy liquid; and continuously filling inert gas to preset pressure, and pulling the shell to finish the directional solidification process. The method can reduce the gas content in the melt, prevent the melt from being oxidized, promote the removal of a surface oxidation film, reduce pores and oxidation film inclusion, and improve the purity, mechanical properties and yield of the casting.

Gas-shielded arc welding in which the tip-to-work distance changes is configured so that fluctuations in welding current are curbed while arc length control is maintained. This is achieved with a corrected current calculating unit that includes a first controlling expression where a first gain G1 is multiplied by an instantaneous voltage error value that is the difference between an instantaneous output voltage setting value and an output voltage detection value, and / or a second controlling expression where a second gain G2 is multiplied by an average voltage error value that is the difference between an output voltage setting value and an average output voltage detection value of a pre-set period of time, determines an arc property gain G1 and / or G2 based on a torch position detection value determined by a torch position determinator, and calculates a corrected current based on the first and / or the second controlling expression.

The utility model discloses a dismounting and mounting structure for a welding gas protection cover, which comprises a welding gun connector, a contact tube is arranged at the bottom end of the welding gun connector, and a fixing sleeve is mounted on the outer side of the welding gun connector; a fixing mechanism is arranged on the outer side of the welding gun connector, and a connecting assembly is arranged in the fixing mechanism. Wherein the fixing mechanism comprises a first arc-shaped cover and a second arc-shaped cover, the first arc-shaped cover and the second arc-shaped cover are connected to the outer side of the welding gun connector in a sleeving mode, and a first connecting plate is installed on one side of the first arc-shaped cover, so that the effect of rapidly splicing and fixing the first arc-shaped cover and the second arc-shaped cover can be achieved; the first arc-shaped cover and the second arc-shaped cover are quickly and conveniently mounted and dismounted, so that the operation difficulty and time in a narrow space can be greatly reduced, the cleaning efficiency of the first arc-shaped cover and the second arc-shaped cover is improved, and the situation that a gas circuit is blocked and the welding quality is influenced is avoided.

The invention provides a Q890qE and Q420qE bridge steel vertical position butt welding method which comprises the following steps: step 1, polishing and derusting a single-side V-shaped joint groove of a steel plate according to standard requirements to expose metallic luster; step 2, preheating the welded joint by adopting an electric heating mode, wherein the preheating temperature is 75 + / -5 DEG C; step 3, pasting a ceramic liner on the reverse side of the groove; 4, solid welding wire CO2 gas shielded welding, single-face welding double-face forming and multi-layer and multi-pass welding modes are adopted till the groove is filled; 5, the ceramic liner on the back face of the weld joint is removed and cleaned up; and 6, post-heat treatment is conducted on a welded joint after welding, the post-heat temperature ranges from 200 DEG C to 250 DEG C, after heat preservation is conducted for 3 hours, a power source is turned off, and the welded joint is naturally cooled to the room temperature. The method is excellent in welding quality and mechanical property, efficient in welding and suitable for popularization.

The invention discloses an all-position welding process stability evaluation method based on the mechanical property of a gas shield welding wire. The method comprises the following steps that S1, the mechanical property of the welding wire is measured; s2, the elastic-plastic ratio rD and the strain strengthening factor sD of the welding wire are obtained; s3, constructing a wire feeding stability comprehensive factor SWF; and S4, a criterion of wire feeding stability and all-position welding process stability is established, and therefore all-position welding process stability evaluation is conducted on the to-be-evaluated welding wire. According to the method, the stability of the gas shield solid welding wire all-position welding process can be indirectly evaluated without actual arc-starting welding.

The invention provides a bridge steel combined welding method. A groove is an asymmetric V-shaped double-faced groove. GMAW-Ar (argon-rich mixed gas shielded welding) and SAW (submerged arc welding automatic welding) combined welding is adopted, a solid welding wire, a submerged arc welding wire and a welding flux are selected, and welding is conducted in a multi-layer and multi-pass mode; an alloy system of chemical components of the submerged arc welding wire is Mn-Ni-Cr-Mo, rare earth elements are added in the formula, and high-purity deposited metal is obtained while grains are refined. By means of the method, welding of the ultrahigh-strength steel above the 890 MPa grade of the Q890qE bridge is achieved, the mechanical property of a welded joint is excellent, and the welding efficiency is high; the mechanical property index of a welded joint is higher than the required value RP0.2 > = 890, Rm > = 1000,-40 DEG C KV2 > = 54J, and A > = 12%; as the steel plate strength is improved, the bridge span is increased, and the number of piers is reduced; as the steel plate is thinned, the welding workload is reduced, and the preheating requirement is lowered; along with reduction of the weight of the bridge member, transportation and bridge site hoisting operation are more convenient.

The invention belongs to the technical field of pipeline installation and construction, particularly relates to a welding unit of a non-consumable electrode gas shielded welding type internal welding machine, and aims to solve the problem of welding spatter during welding. The non-consumable electrode gun head comprises a frame and a non-consumable electrode gun head assembly installed on the frame. The non-consumable electrode gun head assembly comprises a gun seat body mounted on the frame, a tungsten electrode mounted on the gun seat body, a ceramic gas guide cover mounted on the gun seat body and used for covering the tungsten electrode, and a welding wire mounted on the gun seat body and spaced from the tungsten electrode; the tip of the tungsten electrode penetrates out of the ceramic gas guide cover, and the end of the welding wire is inserted into a molten pool in a welding seam. According to the invention, the non-gas metal arc welding unit is adopted to replace the existing gas metal arc welding unit, so that the welding of the inner circumferential weld of the pipeline without splashing is realized.