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917 results about "Submerged arc welding" patented technology

Submerged arc welding (SAW) is a common arc welding process. The first patent on the submerged-arc welding (SAW) process was taken out in 1935 and covered an electric arc beneath a bed of granulated flux. Originally developed and patented by Jones, Kennedy and Rothermund, the process requires a continuously fed consumable solid or tubular (metal cored) electrode. The molten weld and the arc zone are protected from atmospheric contamination by being "submerged" under a blanket of granular fusible flux consisting of lime, silica, manganese oxide, calcium fluoride, and other compounds. When molten, the flux becomes conductive, and provides a current path between the electrode and the work. This thick layer of flux completely covers the molten metal thus preventing spatter and sparks as well as suppressing the intense ultraviolet radiation and fumes that are a part of the shielded metal arc welding (SMAW) process.

Marine engineering large thick steel plate submerged arc welding process method in low-temperature environment

The invention belongs to the field of welding, in particular to a process method applicable to marine engineering large thick steel plate submerged arc welding in low-temperature environment, which comprises a welding method, welding material selection, a welding order, a welding process and the selection and control of various welding process parameters. The method renders with carbon dioxide gas protection welding, and fills and faces through an automatic submerged arc welding; stops welding when the welding reaches more than two thirds of the thickness of a large groove during the welding process, clears chips on the back side and completes the welding of the other side; finally completes the welding of the first side; strictly controls all relevant process parameters of the welding during the welding process, and solves the problems of poorer anti-crack toughness of welding seams and heat affected zones caused by too high cooling speed of the welding seams and too high temperature; can ensure good anti-crack toughness of a welding seam connector without heat treatment after welding; and can meet the requirements of welding of an E36 plate with the thickness of 35 to 77mm under the working environment at the temperature of above -30DEG C, simplifies the production process, shortens the production cycle and reduces the cost.
Owner:PENGLAI JUTAL OFFSHORE ENG HEAVY IND CO LTD

Girth welding technology for vacuum container

ActiveCN102357741AGuaranteed absolute penetrationAvoid the phenomenon of localized high temperatureArc welding apparatusWorkpiece edge portionsShielded metal arc weldingButt welding
The invention discloses a girth welding technology for a vacuum container, which comprises the following steps: processing beveled edges, assembling and welding. In the step of processing the beveled edges, a 14mm thick 0Cr18Ni9 austenitic stainless steel material is selected as a cylinder base material, X-shaped beveled edges are adopted, an inside beveled edge is processed for 10mm with a single-side angle of 32.5 degrees, an outside beveled edge is processed for 4mm with a single-side angle of 35 degrees, and no truncated edge is left. In the step of assembling, reserved clearances of 2.0-2.5mm are assembled, argon tungsten-arc welding is adopted to position, a positioning welding length is 10-15mm, an interval is 200mm, and then a 'strut having a shape of Chinese character 'mi' which is used for adjusting the roundness of a cylinder is welded in the cylinder. In the step of welding, an argon arc welding double-gun butt-welding method is used for bottoming the interior of the cylinder, two layers are filled in an inner welding bead of the cylinder in the manner of manual arc welding, an external welding bead is covered in the manner of submerged-arc welding, and finally, the inner welding bead is covered in the manner of manual arc welding. The girth welding technology can be used for controlling the welding deformation and has the advantages that the method is simple and is easy to realize.
Owner:无锡市创新低温环模设备科技有限公司

Butt joint submerged-arc welding method of bridge steel with tensile strength more than 690Mpa grade

The invention relates to a butt joint submerged-arc welding method of bridge steel with tensile strength more than 690Mpa grade, overcoming the defects that at the present, bridge steel and other engineering structural steel which are in 690Mpa strength grade needs preheating before welding and heat treatment after welding and has severe welding environment and the like during manual and gas protective welding. The butt joint submerged-arc welding method comprises the following steps: adopting steel with tensile strength Rm of between 690Mpa and 745Mpa, the yield strength ReL of between 550 and 690Mpa, the extension rate A of between 19 percent and 21 percent, KV2 ballistic work of between 165J and 180J at 40 DEG C below zero and the thickness of 40mmm, and adopting same-thickness butting;adopting matched welding wires with the tensile strength more than 690Mpa and diameter phi of 4.0mm, and using CHF105 as a welding flux; adopting a double-sided X-type asymmetrical submerged-arc welding groove with the angle of 60 degrees and the truncated edge of 5mm; continuously welding until welding seams are full, and under the conditions that the welding current is 570A, the voltage is 31V,the speed is 35cm/min and the linear energy is 30kj/cm; baking the welding flux for 1 hour at 350DEG C and keeping the temperature of welding layers between 100 DEG C and 150DEG C.
Owner:武钢集团有限公司

Method for manufacturing double metal composite wear-resistant metallurgical rollers

ActiveCN103009015AIncrease the amount of steelAvoid Roll Breaking AccidentsArc welding apparatusWear resistantHardness
A method for manufacturing double metal composite wear-resistant metallurgical rollers includes steps of roller core processing, preheating, surfacing of a composite layer, finish machining and thermal treatment. The roller core processing step includes subjecting steel good in tensile strength, yield strength and impact resistance to forging, pressing and tempering, manufacturing roller core blanks, subjecting the roller core blanks to rough machining to reserve size for a surfaced composite layer. The preheating step includes preheating the roller cores to the optimum surfacing temperature of 380 DEG C +/- 5 DEG C. The surfacing step of the composite layer includes surfacing and filling the reserved surfaced composite layer by flux-cored wires on the surface of the preheated roller cores by means of submerged-arc welding process. The finish machining step includes processing the surfaced double metal composite wear-resistant metallurgical roller blanks into design size. The thermal treatment step includes quenching and tempering the double metal composite wear-resistant metallurgical rollers subjected to finish machining, so that the surfaces of the double metal composite wear-resistant metallurgical rollers can meet the requirements for good anti-sticking abrasion, grain abrading resistance, red hardness, resistance to cold and hot fatigue, and peeling resistance.
Owner:邯郸市永固冶金备件有限公司

Method for welding Q500qE ultralow-carbon bainite steel for bridge

The invention provides a method for welding Q500qE ultralow-carbon bainite steel for a bridge. The method is excellent in joint mechanical performance and high in welding efficiency and specifically includes that aiming at specific chemical components, applicable technical conditions and different plate thicknesses of the Q500qE ultralow-carbon bainite steel for the bridge, preheating temperature before welding, groove types and welding process parameters are determined; a welding joint type adopts butt joint, penetration angle joint or ship position T-shaped angle joint; a welding method adopts submerged arc welding, CO2 gas shielded semiautomatic welding or shielded metal arc welding. By the welding method, the joint type and thickness specifications of a bridge structure are comprehensively covered, the technical scheme is simple, convenient and high in adaptivity, all implementing effects meet technical requirements of standards related to building of bridge steel and the bridge structure, and the method is of great significance in promoting upgrading of the bridge steel and development of large-span steel bridge building technology. The method can be applied to building of the bridge structure, can also be applied to welding of other ultrathin-carbon bainite steel and is high in adaptivity.
Owner:CHINA RAILWAY SHANQIAO GRP CO LTD

Technology for repairing surfacing of piston rod of super large marine diesel engine

InactiveCN101444881ALow roughness requirementsLow cleanliness requirementsArc welding apparatusRoom temperatureEngineering
The invention discloses a technology for repairing surfacing of a piston rod of a super large marine diesel engine, and the technology can carry out the deep repair of the surface of the piston rod. The adopted surfacing process is as follows: flaw detection and straightening are carried out on the piston rod, turning machining is carried out on the surface of the piston rod to remove a defect layer, and individual deeper cracks are manually removed by grinding; fire whirl is used for heating the piston rod twice, the first heating is carried out till 200 DEG C-250 DEG C, the heating is stopped, the race rotation is carried out for 30 minutes, the second heating is further carried out after the temperature difference between the interior and the exterior is reduced, and a surfacing machine tool is rotated after reaching 250 DEG C-300 DEG C; submerged arc welding is used for rotating dual heads of the surfacing machine tool and a 2Cr13 flux-cored welding wire for carrying out the simultaneous surfacing, and asbestos cloth is used for wrapping and keeping the temperature during the welding process; the piston rod wrapped by the asbestos cloth for slow cooling after the surfacing achieves the size requirement, when the temperature is decreased to be lower than 100 DEG C, the piston rod wrapped by the asbestos cloth is vertically placed till the temperature is decreased to the room temperature, and then the temperature-keeping cloth is removed. The surface of the piston rod after the repair by employing the method has no weld defects, the piston rod fully meets the performance requirements, and the cost is only about one fifth of the cost for fabricating a new piston rod.
Owner:DALIAN XINZHONG GRP +1

Method for manufacturing X70 steel-level large deformation-resistant longitudinally submerged arc welding pipe

The invention discloses a method for manufacturing X70 steel-level large deformation-resistant longitudinally submerged arc welding pipes, which is applied to the manufacture of special welding pipes for oil and gas transmission. In the method, a controllable rolled steel plate is used, wherein the controllable rolled steel plate has a ferrite-bainite double-phase metallurgical microstructure and contains the following chemical components: 0.04 to 0.07 percent of C, 1.60 to 1.85 percent of Mn, 0.15 to 0.30 percent of Si, not more than 0.003 percent of S, not more than 0.010 percent of P, 0.15 to 0.30 percent of Ni, not more than 0.020 percent of Ti, 0.015 to 0.040 percent of Al, 0.010 to 0.065 percent of Nb, not more than 0.006 percent of N, not more than 0.30 percent of Cu, 0.10 to 0.25 percent of Cr, and not more than 0.0005 percent of B. The method comprises the following steps: (1) milling edges of the steel plate; (2) pre-bending bended edges; (3) performing JCO forming; (4) pre-welding joint seams; and (5) performing finish-welding on the inner and the outer sides of the joint seams. The method is applied to the manufacture of large-deformation-resistant welding pipes which are used in seismic belts, frozen soil areas, landslide area and other areas with high risk of deformation. The method has the advantages as follows: in the JCO forming process, the local deformation amounts and straight edge sizes of the steel plate in different rolling passes are analytically acquired according to the width, thickness and strength of the steel plate and the size of a die so as to determine the rolling passes and ensure uniform deformation at all parts of the steel plate after forming; and in the diameter expansion process, the minimum diameter expansion amount is determined according to the size and shape of the formed steel pipe, so as to ensure the size, shape and physiochemical properties of the steel pipe after diameter expansion.
Owner:CNPC BOHAI EQUIP MFG +2

Super-thick steel plate welding method

ActiveCN104384677AImprovement design is reasonableImproved Design ReliabilityWelding/soldering/cutting articlesMetal working apparatusSocial benefitsHydrogen
The invention relates to a super-thick steel plate welding method. According to the method, the fabrication weldability of super-thick steel can be effectively improved, and the construction efficiency and the weld inspection first-pass yield can be improved. The method comprises the following steps of 1, processing a welding groove; 2, preparing before welding; 3, preheating before welding; 4, welding. The method is simple; the improved design of the welding groove is reasonable and reliable, and the method is suitable for common domestic single wire submerged arc welding machines and is high in practicability; a combined welding process of taking super low hydrogen electrode arc welding as backing weld and adopting submerged arc welding for filling and cosmetic welding is adopted, and the welding advantages of the two processes are integrated; the fabrication weldability of the super-thick steel plate is greatly improved, the welding quality of the super-thick steel plate is controlled, the first-pass yield of super-thick steel plate butt weld inspection is improved, and the method can be widely applied to welding construction of low-alloy high-strength structural steel super-thick steel plates which are 60-300mm in thickness and has good technical, economic and social benefits.
Owner:NO 9 METALLURGICAL CONSTR

Deposition forming manufacturing method of parts and molds

The invention discloses a deposition forming manufacturing method of parts and molds, and belongs to the field of non-mold growing manufacturing and remanufacturing. The method comprises the following steps that S1, the three-dimensional CAD model of a workpiece to be formed is subjected to hierarchical slicing; S2, the CNC codes of all hierarchical slices are acquired; S3, deposition forming is conducted layer by layer according to the CNC codes of all the hierarchical slices, the fine portions of the workpiece are formed by laser, and one or more technologies in electric arc welding, electron beam welding, electroslag welding and submerged-arc welding is or are adopted to form the thick wall and the non-fine portions of the workpiece; or in the S3, a heat source which is compounded by laser beams and gas protection electric arcs or a heat source which is compounded by the laser beams and vacuum protection electronic beams is adopted for forming the thin wall and the fine portions of the workpiece, and the gas protection electric arcs or the vacuum protection electron beams are shut down. According to the deposition forming manufacturing method, direct deposition forming can be achieved to obtain parts and molds which are stable in structure property and high in manufacturing precision and are provided with thin walls or fine portions.
Owner:HUAZHONG UNIV OF SCI & TECH

Welding method of stainless steel clad plate

The invention discloses a welding method of a stainless steel clad plate, and relates to the technical field of welding. The welding method comprises the following steps that surface oxygen complexes of the stainless steel clad plate are removed; a groove is machined, the groove is an X-shaped groove, the angle of the groove is 55-65 degrees, the root gap of the groove is 1-3 millimeters, and the root portion of a joint is placed in a base layer; a base layer is welded, a first welding layer and a third welding layer of a welding seam of the base layer are welded in a submerged automatic arc welding mode, the third welding layer is provided with a plurality of welding beads, and a second welding layer is welded in a gas metal arc welding mode; a transitional layer on the connecting portion of the base layer and a multiple layer is welded, a fourth welding layer and a fifth welding layer of the transitional layer are both welded in the gas metal arc welding layer; the multiple layer is welded, a welding seam of the multiple layer is a sixth welding layer, and the sixth welding layer is welded in a large-current submerged-arc welding mode. Compared with the prior art, the welding method of the stainless steel clad plate improves the quality of a welding joint of the stainless steel clad plate and is high in welding efficiency.
Owner:WUZHOU WANGJIE MACHINERY MFR

Submerged arc-welding method of steel for high strength pressure vessel

The invention discloses a submerged arc-welding method of thick steel slab for large pressure vessel with tensile strength of 610-670 MPa, which solves the currently existing defects that the impact energy of deposited metal and the actual joint tenacity can not meet the welding requirements for the production of large high-strength thick steel slab structure. A measure adopted by the invention is as follows: the method comprises the following steps of: adopting pressure vessel steel with tensile strength of 610-760 MPa and thickness of 44mm to 55mm; using matched welding materials: the tensile strength of a welding wire is 610-670 MPa with diameter of 4.0mm and welding flux SJ105Q is adopted; adopting an unsymmetrical double-side V-shaped groove with an angle of 60 degrees as the groove of submerged arc-welding and a blunted edge of 4mm; continuously welding at the butt joint till weld seams are filled up under the conditions of 700A welding current, 36V voltage, 30cm/min speed and 50kJ/cm energy input; using a welding flux roasting system of 350 DEG C multiplied by 1h; and adopting interlayer temperature of 100 DEG C to 150 DEG C. In the invention, preheating is not required before welding and heat treatment is not needed after welding and joints have good low temperature impact toughness and safety storage.
Owner:WUHAN IRON & STEEL (GROUP) CORP

Determination method for heat source model parameters in multiplewire submerged-arc welding by numerical simulation

The invention discloses a determination method for heat source model parameters in multiplewire submerged-arc welding by numerical simulation. The determination method comprises the following steps of: determining a heat-flow density distribution function in the multiplewire submerged-arc welding process; initially determining the heat source model parameters, wherein the heat source model parameters to be determined includes Ui, Ii, v, n, taui, etai, alphai, f<fi>, bi, ci, a<fi>, and a<bi>; and finally determining a heat-source model, wherein the determined parameters are substituted into the heat-flow density distribution function q(x, y, z, t) which is then taken as a thermology boundary condition for repeated iterative computations by a numerical simulation tool, the computation result of iterative computation of each time is compared with the shape of a joint fusion pool obtained by actual welding, the heat-source model parameters bi, ci, a<fi>, a<bi> are gradually adjusted by a range of 5% according to the comparison results until the errors between the parameters of the fusion depth and the fusion width of a simulated fusion pool and the fusion depth and the fusion width of the actual joint fusion pool are smaller than 10%, and then the determination of the heat-source model parameters in the multiplewire submerged-arc welding is finished.
Owner:CNPC BOHAI EQUIP MFG +1

Double arc four wire automatic arc-submerging welder and manufacture method thereof

ActiveCN101306488AMeet the welding process requirementsImprovement of process technical parametersWelding accessoriesWelding power supplyEngineering
The invention discloses a double-arc four-wire automatic submerged arc welding machine and the manufacturing method thereof. The automatic submerged arc welding machine include a welding power supply, an upright post which is arranged on a trolley and a running gear and is provided with a top part with a lifting mechanism, a cross arm which is movably connected with the lifting mechanism and can move up and down along the upright post, a welding head which is equipped with a welding gun and a solder hopper, a wire guide arranged between the welding gun and a welding wire spool, a wire feeding device, a swing mechanism which is arranged on the trolley and is used for control the upright post to rotate relatively to the trolley, and an electric control cabinet which is fixed on the upright post. Compared with the prior art, the double-arc four-wire automatic submerged arc welding machine of the invention has the advantages as follows: the structure is novel, the arrangement is reasonable; the process engineering parameters such as power efficiency and so on are improved for satisfying technological requirements of welding a gas steam turbine; the welding efficiency can be increases by at least three times; a machine head, an operator seat lifting arm, a corner, a falling protector and other devices are arranged; the solder can be automatically reclaimed and fed, and applied continuously, thereby reducing labor intensity, improving operational environment and conducing to operation.
Owner:SHANGHAI ELECTRIC POWER GENERATION EQUIPMENT CO LTD

Special flux-cored wire for carrying out preheating-free and heat treatment-free surfacing repair and reproducing on shaft and gear parts

The invention belongs to the field of material science and engineering and relates to a special flux-cored wire for carrying out preheating-free and heat treatment-free surfacing repair and reproducing on shaft and gear parts. The special flux-cored wire comprises the following chemical compositions in percentage by weight: 5 to 10 percent of fluorite, 20 to 40 percent of high-carbon ferrochrome, 5 to 10 percent of high carbon ferromanganese, 5 to 10 percent of ferrosilicon, 5 to 10 percent of ferromolybdenum, 10 to 15 percent of rare earth oxide, 15 to 20 percent of metallic nickel, 2 to 5 percent of ferrovanadium, 2 to 5 percent of ferrocolumbium, 2 to 5 percent of ferrotitanium, 0.1 to 0.5 percent of graphite, 5 to 15 percent of iron powder, 0.5 to 2 percent of nitride and 1 to 3 percent of aluminum magnesium alloy. A sheath of the special flux-cored wire is a low-carbon steel strip. The special flux-cored wire can be suitable for open arc welding or submerged arc welding. The series flux-core wire for surfacing can carry out surfacing repair and reproducing on the shaft and gear parts under the conditions that preheating is free before surfacing and heat treatment is free after surfacing. The surfacing metal has high crack resistance. The performance of the repaired parts is equal to or even superior to that of the original parts. The special flux-cored wire is convenient to use on site. The hardness range is between HRC20 and HRC45. The service life of the repaired parts is about 3 times longer than that of the original parts.
Owner:YANSHAN UNIV

Large straight-line joint submerged arc welding tube fast production process

The invention provides a big vertical masonry joint hidden arc welding tube fast production method belonging to the processing and forming fields of metal plate and relating to the bending processing and forming technology of metal plate which is mainly used for the fast production of the big vertical masonry joint hidden arc welding tube. The invention adopts continuous array rollers of a coil stock to form, high frequency prewelding on line, then utilizing a off-line automatic submerged arc welding to carry out the inner welding and outer welding of the welded pipe as well as expanding, water pressure and nondestructive examinations; thereby realizing the high efficiency production of the big vertical masonry joint hidden arc welding tube products. The invention adopts a plate-coiling mode to supply materials, cutting materials, shearing and butt welding, utilizes milling edge to finish the online-processing of a divided edge beside the plate, primary roller forming, fine roller forming, high frequency prewelding after a rough material is continuously formed by the array rollers and sawing as well as baiting and the steel tube rough material needed by a hidden arc welding working procedure can be acquired through online dimension fixing and cutting off; hidden arc inner welding and hidden arc outer welding, inner control examination, expending, water pressure test, repairing ends by machinery are carried out on the steel rough material to exam to acquire a finished product. The technique has a reasonable design and has the advantages of good steel tube forming quality and high production efficiency as adopting the array rollers to form and high frequency prewelding; thereby ensuring the overall production efficiency of the technique and the welding line quality can also be ensured reliably.
Owner:PANYU ZHUJIANG STEEL PIPE LIANYUNGANG

Submerged-arc welding root welding and back chipping process of thick plate with K-type groove

InactiveCN102554416AShorten welding auxiliary timeShorten welding timeArc welding apparatusThick plateSlag
The invention discloses a submerged-arc welding root welding and back chipping process of a thick plate with a K-type groove. The K-type groove is an asymmetric K-type groove, an upper open angle and a lower open angle of the groove are both 45 degrees to 50 degrees, and truncated edges are not reserved at the root. During assembly, groove clearance of 2mm to 3mm is reserved. During welding, solid gas protection welding wires under pulse current are adopted for backing welding of a root pass of the front side of a K-type groove test piece, and after the root pass is thoroughly fused, a part of weld metal penetrates through the reverse side of the groove to achieve backing welding. After welding, back chipping of the reverse side is performed. Finally, gas shielded welding under large current is adopted for fusion welding of the roof of the reverse side groove, and gas rich in argon is used as protective gas. The submerged-arc welding root welding and back chipping process reduces time for slag removal of root pass of submerged-arc welding and polishing and finishing of the reverse side groove of the welding test piece, improves welding efficiency by more than 30%, removes a carbon arc gouging process, decreases welding noises and dust emission, lowers labor intensity of welders and reduces time for damaging workers under high-decibel noises.
Owner:725TH RES INST OF CHINA SHIPBUILDING INDAL CORP

Welding method of deck structure of stainless steel compound plate for railway steel bridge

ActiveCN101797667AGuaranteed weld thicknessGuaranteed uncertaintyArc welding apparatusWelding/soldering/cutting articlesAusteniteTransition layer
The invention discloses a welding method of a deck structure of a stainless steel compound plate of a railway steel bridge, which comprises the following steps: selecting structural steel for a bridge with thickness of 16-20mm as a base layer, selecting austenitic stainless steel with thickness of 2-4mm as a multiple layer, and removing 3-6mm of cladding material materials at each of two edges of welding grooves in advance, wherein the groove angle is 45-65 degrees, and the groove spacing is 4-8mm; the method comprises the following steps: firstly, assembling positioned welding, and then, carrying out backing welding by CO2 gas shielded welding; then, carrying out welding of the base layer by submerged-arc welding; and finally, carrying out welding of a transition layer and the multiple layer by the CO2 gas shielded welding. By adopting a specific groove type, the invention eliminates uncertain human factors and solves the problems that the thickness of the deposited metal of the base layer is insufficient, the multiple layer can be molten by mistake when the substrate layer is welded, and the like; the reverse formation is good, so that the reverse back gouging process is omitted; and the invention has the advantages of good assembly quality and easy realization of mechanization and automation, improves the production efficiency, and is convenient for ensuring the corrosion resistance of the multiple layer.
Owner:725TH RES INST OF CHINA SHIPBUILDING INDAL CORP

Field welding method of domestic A335 P91 high-pressure thick-wall pipe

The invention provides a field welding method of a domestic A335 P91 high-pressure thick-wall pipe, and belongs to the technical field of welding. A welded part of a welded pipe is processed as a double-V-shaped groove; a process of welding 3 layers for bottoming by using manual argon arc welding GTAW and filling a cover surface by using automatic submerged arc welding SAW is adopted; multi-layer and multi-pass welding is adopted; each layer of welding line sections is decreased; and the welding line crystallization conditions are changed, so that the toughness of a welding joint is improved, an overthick welding bead is prevented from narrowing a heat affected zone, and a softening belt of the welding joint is prevented from generating cracks in long-time operation at high temperature; a small-diameter welding wire with a diameter of not more than 2.5 mm and a low-hydrogen welding agent are adopted to weld to reduce the linear energy in the welding process, so that grains of base metal are refined, and the possibility of generating such defects as air holes and cracks in welding lines is reduced; and compared with a traditional manual welding method, the field welding method effectively shortens the heat treatment and welding period, improves the welding line quality and the welding efficiency, relieves the labor intensity of welders, and saves the construction cost.
Owner:THE SIXTH CONSTR CO LTD OF CHINA NAT CHEM ENG
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