CN113560701A - Submerged arc welding operation step and method - Google Patents
Submerged arc welding operation step and method Download PDFInfo
- Publication number
- CN113560701A CN113560701A CN202110906853.1A CN202110906853A CN113560701A CN 113560701 A CN113560701 A CN 113560701A CN 202110906853 A CN202110906853 A CN 202110906853A CN 113560701 A CN113560701 A CN 113560701A
- Authority
- CN
- China
- Prior art keywords
- welding
- arc
- submerged arc
- wire
- seam
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
Images
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
- B23K—SOLDERING OR UNSOLDERING; WELDING; CLADDING OR PLATING BY SOLDERING OR WELDING; CUTTING BY APPLYING HEAT LOCALLY, e.g. FLAME CUTTING; WORKING BY LASER BEAM
- B23K9/00—Arc welding or cutting
- B23K9/18—Submerged-arc welding
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
- B23K—SOLDERING OR UNSOLDERING; WELDING; CLADDING OR PLATING BY SOLDERING OR WELDING; CUTTING BY APPLYING HEAT LOCALLY, e.g. FLAME CUTTING; WORKING BY LASER BEAM
- B23K33/00—Specially-profiled edge portions of workpieces for making soldering or welding connections; Filling the seams formed thereby
- B23K33/004—Filling of continuous seams
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
- B23K—SOLDERING OR UNSOLDERING; WELDING; CLADDING OR PLATING BY SOLDERING OR WELDING; CUTTING BY APPLYING HEAT LOCALLY, e.g. FLAME CUTTING; WORKING BY LASER BEAM
- B23K9/00—Arc welding or cutting
- B23K9/235—Preliminary treatment
Landscapes
- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Physics & Mathematics (AREA)
- Plasma & Fusion (AREA)
- Arc Welding In General (AREA)
- Butt Welding And Welding Of Specific Article (AREA)
Abstract
The invention relates to the technical field of welding, in particular to a submerged arc welding operation step and a submerged arc welding operation method, and provides the following scheme aiming at the problems that the existing welding technology can not realize intellectualization mostly, the welding condition can not be observed during welding, and the welding success rate of a welded product is low because the wrong welding can not be found in time, wherein the method comprises the following steps: s1: process preparation, S2: welding process, S3: the invention aims to weld by a submerged arc method, has high thermal efficiency and large fusion depth, reduces the amount of filled metal when the groove of a weldment is smaller, reduces the welding cost, adopts a welding machine to weld and uses an explosion-proof infrared camera to monitor in real time, can correct welding errors in the welding process in time, increases the productivity of the weldment, realizes the primary intelligence of welding and provides a new direction for the intelligence of a welding process.
Description
Technical Field
The invention relates to the technical field of welding, in particular to submerged arc welding operation steps and a submerged arc welding operation method.
Background
Welding is an important processing technology in the manufacturing industry, is an accurate, reliable and cost-effective technology, adopts a high-tech connecting material method, has no other method which can be more directly and widely applied to metal connection than welding at present, and increases a larger additional value for a welded product.
However, most of the existing welding technologies cannot realize intellectualization, the welding condition cannot be observed during welding, and the productivity of weldments is low due to the fact that wrong welding cannot be found in time.
Therefore, we propose a submerged arc welding procedure and method to solve the above problems.
Disclosure of Invention
The invention aims to solve the problems that most of the existing welding technologies cannot realize intellectualization, the welding condition cannot be observed during welding, the welding success rate of a welded product is low due to the fact that wrong welding cannot be found in time and the like, and provides a submerged arc welding operation step and a method.
In order to achieve the purpose, the invention adopts the following technical scheme:
a submerged arc welding procedure and method comprising the steps of:
s1: preparation of the process: preprocessing equipment, tools and welding raw materials required by welding before welding;
s2: and (3) welding: operating a welding machine to weld and monitoring in real time, paying attention to the residual flux and supplementing the flux in time;
s3: and (3) completing welding: after welding, the welding points are checked and cleaned, and corresponding measures are taken;
preferably, in S1, the required devices include an automatic submerged arc welding machine, a boom car, a control box, a trolley walking turntable, a roller frame, an explosion-proof infrared camera, a interphone, a flux recycling box and a flux oven, the required tools include a wire cutter, a chisel or a cold pump gun, a hammer, a brush, a file and a screen, the required raw materials include carbon steel and low alloy steel, the wearing of workers in a welding workshop must meet PPE requirements, the PPE requirements include that the workers must wear work clothes and safety shoes when entering the workshop, and wear protective earplugs, protective glasses, a dust mask, protective gloves and safety helmets, the welding materials are pretreated by removing oil stains, oxide skin, rust and moisture in a range of 150mm on a welding groove and an edge thereof, and the ratio of the width to the depth of the root-removing groove is greater than 1: 1, deoiling by adopting a fire drying method, polishing by using a steel wire ball during deoxidation until the unoxidized part of the groove is exposed, derusting by adopting a grinding wheel brush, single-piece sand blasting and acid washing, derusting, deoxidizing and deoiling the welding wire during coiling the welding wire, wherein, the rust part of the welding wire is wiped by dilute sulphuric acid solution to remove rust on the welding wire, high-temperature antioxidant is adopted to remove oxidation, the welding wire is wiped manually to remove oil stain, the welding flux is dried in advance, the baking temperature and time are carried out according to TT1-WI-TQ-040 welding material quality control regulation, meanwhile, the polarity of welding equipment, welding materials and a power supply of newly-installed equipment is checked, the gouging oxidation slag in the groove is thoroughly cleaned before welding, meanwhile, whether welding equipment and welding materials meet requirements and the polarity of a power supply of the newly-installed equipment are checked, and before welding, air gouging oxidation slag in the groove is thoroughly cleaned;
preferably, in S2, the longitudinal seam welding is performed by installing a leading and quenching arc plate, the material, thickness and groove size of the leading and quenching arc plate are the same as those of the base metal, the size is not less than 80 × 150mm, the length of the leading and quenching arc welding seam is within the range of 80mm-100mm, after the leading and quenching arc plate is grooved, the carbon-planed metal slag is cleaned and welded, after the welding is completed, the leading and quenching plate is cut off, the base metal cannot be damaged when the leading and quenching arc plate is cut, the welding material used for positioning welding meets the requirements in WPS, the position of the welding material is generally the back of the first welding seam, the length of the welding material is more than 50mm, the thickness of the welding meat is 2-4mm, the welding seam is kept flat during shunting, a space is left for the next arc, the welding machine is preheated before the welding, the preheating standard is strictly performed according to the WPS or process operation instruction, the precise pairing is performed during the pairing to prevent the root from being not fused due to serious miscarriage, if the welding current is increased, the arc voltage is correspondingly increased, the arc voltage is low when a root welding seam is carried out, the welding speed is high, if the welding speed is too low, crystal grains are large, the mechanical property of the welding seam is easy to reduce, the welding current avoids difficult undercut and slag removal according to requirements, if the root penetration is ensured, the current can be slightly large but cannot exceed the upper limit of welding parameters of field project products, submerged arc welding is short-circuit arc striking, the welding machine has higher no-load voltage and larger short-circuit current, the arc striking is easier, but the too large current (when the voltage is lower) can cause small forming coefficient (fusion width is larger than fusion depth) and cracks are easy to generate, if a groove is wider, multiple welding is adopted on the same layer, the overlapping amount between two welding passes is 1/3-1/2 of fusion width, and the welding wire head is conveniently struck by using a steel wire clamp sharp corner or a grinder to be thinner, the contact tightness of a welding wire and a workpiece is suitable, the welding wire can be easily scratched as a standard, backing welding, tack welding or previous defects can be cleaned up to carry out next welding, the position of the welding wire is accurate, wherein the smaller the diameter of the workpiece is, the larger the requirement of an offset value b is, the smaller the value b is, the deviation value is 40-80mm, a rotary table is started firstly during circular welding to enable the welding wire to be wiped with the workpiece, then power is turned on to start arc, in addition, when submerged arc welding is carried out, a welding machine control circuit stops wire feeding firstly and then powers off, a longitudinal welding line is subjected to arc blowout on an arc blowout plate, arc pits are completely arranged outside the workpiece, the length is 70-100mm, the arc blowout starting position of the circular welding line is positioned within 300-500mm of the intersection of the longitudinal and circular welding lines, the length of an arc blowout overlapping area is not less than 50mm, if arc starting and blowout in other areas are required to be marked in time, before welding a next welding line, dregs on the previous welding line are cleaned up, the used welding flux is executed according to TT1-WI-TQ-040 welding material quality management regulation, the welding process is not allowed to undercut in principle, if undercut occurs, the local undercut depth of the cover surface and the root of the undercut is controlled within 0.25mm, meanwhile, the residual quantity of the welding flux needs to be noticed all the time during welding, filling needs to be carried out timely when the welding flux is insufficient, and the supplement specification needs to be kept consistent, an explosion-proof infrared camera is arranged at the welding position inside a welding machine during the welding process for real-time monitoring, the camera shooting content is examined in real time by a human operator in a background, the manual examination range comprises whether a welding piece group is accurate and whether a welding error occurs during the welding process, if the group is found to have serious misalignment or the welding error, the error condition needs to be reported and stated to workers in the welding workshop through an interphone immediately, the workers adjust the welding flux by the workers, if the overflow phenomenon occurs, judging by background manual work and reporting the judgment result to workers in a workshop, the workers in the workshop work according to the judgment result, wherein if the welding seam is not welded thoroughly, the welding seam needs to be ground and then re-welded, if cracks appear in the welding seam, repair welding needs to be eradicated regardless of the cracks, if pores appear on the surface, repair welding needs to be performed, if pores appear in the interior, repair welding needs to be performed according to the requirement of welding seam quality grade, if slag inclusion occurs, small slag inclusion is processed according to the pores, strip slag inclusion is determined according to the requirement of ISO 5817B grade, if the welding seam is too wide, the too wide welding seam needs to be ground under the condition of not damaging the base metal, the width of the welding seam is generally 3 +/-1 mm respectively added on two sides of a groove, if other defects which are not listed in the welding process are based on ISO 5817B grade, the requirement of butt welding seam is not lower than the base metal, the residual height does not exceed 10% of the width of the welding seam, the maximum is not greater than 3mm, and if the residual height of the welding seam is higher, two sides of the welding seam are required to form smooth transition or be treated according to the technical specification requirements, the dynamic load is preferably selected to weaken the welding seam, the static load is allowed to select a reinforced welding seam, but the residual height is not more than 3mm, the welding seam is symmetrical fillets without special description, and the long angle edge of the welding throat with the long edge being less than or equal to 1.5mm and 15 percent is accepted;
preferably, in S3, after welding, the butt welding point is inspected and cleaned, the weld seam appearance is inspected by visual inspection, if undercut occurs, weld beading, surface blowholes and other welding points which do not meet quality requirements are repaired, surface cracks are inspected by visual inspection, magnetic powder and penetration of a magnifier which is not less than 6 times, internal defects are inspected by an ultrasonic method, and the misalignment region is thoroughly cleaned during inner side back chipping.
Compared with the prior art, the invention has the beneficial effects that:
1. the submerged arc welding method has the advantages of high thermal efficiency, large fusion depth, reduced metal filling amount when the groove of a welding piece is small, and reduced welding cost.
2. The explosion-proof infrared camera is adopted for real-time monitoring, welding errors in the welding process can be corrected in time, and the productivity of weldment is increased.
3. The welding machine is adopted for welding and real-time monitoring is carried out, so that preliminary intellectualization of welding is realized, and a new direction is provided for intellectualization of a welding process.
The invention aims to weld by a submerged arc method, has high thermal efficiency and large fusion depth, reduces the amount of filled metal when the groove of a weldment is small, reduces the welding cost, adopts a welding machine to weld and uses an explosion-proof infrared camera to monitor in real time, can correct welding errors in the welding process in time, increases the productivity of the weldment, realizes the primary intelligence of welding and provides a new direction for the intelligence of a welding process.
Drawings
FIG. 1 is a flow chart of a submerged arc welding operation and method according to the present invention;
FIG. 2 is a schematic view of the circumferential seam arc starting position of a submerged arc welding operation and method of the present invention;
FIG. 3 is a schematic diagram of the specification requirements for both sides of the weld for a submerged arc welding operation and method of the present invention;
FIG. 4 is a schematic view of a submerged arc welding operation and method according to the present invention, in which severe misalignment is likely to cause root unfused during assembly;
FIG. 5 is a schematic diagram of the quality requirement of the submerged arc welding operation and method of the present invention that the severe misalignment is likely to cause root unfused during assembly;
FIG. 6 is a schematic view of a back gouging groove being too narrow to cause root unfused in a submerged arc welding operation and method according to the present invention;
FIG. 7 is a schematic diagram illustrating the quality requirements of an unfused root map due to the narrow back gouging groove in a submerged arc welding operation and method of the present invention;
FIG. 8 is a schematic diagram of the number distribution and parameters of thick plates of the submerged arc welding operation and method of the present invention are not matched, the edge is poorly formed, and slag inclusion and non-fusion are easily generated at the edge;
FIG. 9 is a schematic diagram of the quality requirements of the submerged arc welding operation steps and method of the present invention, including mismatching of the channel number distribution and parameters of the thick plate, poor edge formation, easy slag inclusion at the edge and incomplete fusion;
FIG. 10 is a schematic diagram of the hidden defect danger caused by unclean defects (cracks, pores and slag inclusions) during back chipping of the submerged arc welding operation step and method provided by the invention;
FIG. 11 is a schematic diagram of quality requirements of hidden defects left when the defects (cracks, pores and slag inclusion) are not cleaned up and are not cleaned up in the process of back chipping of the submerged arc welding operation step and the method provided by the invention.
Detailed Description
The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments.
Example one
Referring to fig. 1-11, a submerged arc welding operation and method includes the steps of:
s1: preparation of the process: the method comprises the steps of preprocessing equipment, tools and welding raw materials required by welding before welding, wherein the required equipment comprises an automatic submerged arc welding machine, an arm frame vehicle, a control box, a trolley walking turntable and a roller frame, an explosion-proof infrared camera, an interphone, a welding flux recycling box and a welding flux oven, the required tools comprise a wire cutter, a chisel or a cold pump gun, a hammer, a brush, a file and a sieve, the required raw materials comprise carbon steel and low alloy steel, and workers enter a welding workshop to wear the welding workshop and must meet PPE requirements, wherein the PPE requirements are that workers must wear working clothes and safety shoes and wear protective earplugs, protective glasses, a dustproof mask, protective gloves and safety helmets, the welding materials are preprocessed by performing degreasing, oxide skin, iron and moisture operations on a welding groove and the edge of the welding groove within 150mm, and simultaneously checking whether the welding equipment and the welding materials meet requirements and the electrical source performance of new installation equipment, thoroughly cleaning the air gouging oxidation slag in the groove before welding;
s2: and (3) welding: operating a welding machine to weld and monitor in real time, installing a leading and quenching arc plate for longitudinal seam welding, cleaning carbon planer metal slag and welding after the leading and quenching arc plate is planed, wherein the material, thickness and groove size of the leading and quenching arc plate are the same as those of a base metal, the size is not less than 80 x 150mm, the length of the leading and quenching arc welding seam is within the range of 80mm-100mm, after the leading and quenching arc plate is planed, cutting the leading and quenching arc plate, the base metal cannot be damaged when the leading and quenching arc plate is cut, welding materials used for positioning welding meet the requirements in WPS, the positions of the welding materials are generally arranged on the back of a first welding seam, the length of the welding materials is more than 50mm, the thickness of welding meat is 2-4mm, the welding seam forming is kept flat when shunting, a space is left for a next electric arc, simultaneously, preheating is carried out by a welding machine before welding, the preheating standard is strictly carried out according to WPS or process operation instruction manual, accurately assembling to prevent the root from being not being fused due to serious wrong edges when assembling, if the welding current is increased, the arc voltage is correspondingly increased, the arc voltage is low when a root welding seam is carried out, the welding speed is high, if the welding speed is too low, crystal grains are large, the mechanical property of the welding seam is easy to reduce, the welding current avoids difficult undercut and slag removal according to requirements, if the root penetration is ensured, the current can be slightly large but cannot exceed the upper limit of welding parameters of field project products, submerged arc welding is short-circuit arc striking, the welding machine has higher no-load voltage and larger short-circuit current, the arc striking is easier, but the too large current (when the voltage is lower) can cause small forming coefficient (fusion width is larger than fusion depth) and cracks are easy to generate, if a groove is wider, multiple welding is adopted on the same layer, the overlapping amount between two welding passes is 1/3-1/2 of fusion width, and the welding wire head is conveniently struck by using a steel wire clamp sharp corner or a grinder to be thinner, the contact tightness of a welding wire and a workpiece is suitable, the welding wire can be easily scratched as a standard, backing welding, tack welding or previous defects can be cleaned up to carry out next welding, the position of the welding wire is accurate, wherein the smaller the diameter of the workpiece is, the larger the requirement of an offset value b is, the smaller the value b is, the deviation value is 40-80mm, a rotary table is started firstly during circular welding to enable the welding wire to be wiped with the workpiece, then power is turned on to start arc, in addition, when submerged arc welding is carried out, a welding machine control circuit stops wire feeding firstly and then powers off, a longitudinal welding line is subjected to arc blowout on an arc blowout plate, arc pits are completely arranged outside the workpiece, the length is 70-100mm, the arc blowout starting position of the circular welding line is positioned within 300-500mm of the intersection of the longitudinal and circular welding lines, the length of an arc blowout overlapping area is not less than 50mm, if arc starting and blowout in other areas are required to be marked in time, before welding a next welding line, dregs on the previous welding line are cleaned up, the used welding flux is executed according to TT1-WI-TQ-040 welding material quality management regulation, an explosion-proof infrared camera is arranged at the welding position in a welding machine for real-time monitoring in the welding process, the camera content is manually checked in real time on a background, the manual checking range comprises whether a welding piece group is accurate or not and whether a welding error occurs in the welding process, if the group is found to have serious edge misalignment or the welding error, the error condition is immediately reported and stated to workers in a welding workshop through an interphone, the workers adjust the welding flux, if the overflow phenomenon occurs, the background manual work judges and reports the judgment result to the workers in the workshop, the workers in the workshop work through the judgment result, wherein if the welding line is not completely welded, the welding line needs to be rewelded after the welding line is ground, if the welding line has cracks, the repair welding is eradicated regardless of the cracks, if the surface has pores, the repair welding is carried out, whether repair welding is required or not is determined according to the quality grade requirement of the welding seam when air holes appear inside, if slag inclusion occurs, small slag inclusion is processed according to the air holes, long slag inclusion is determined according to the ISO 5817B grade requirement, if the welding seam is too wide, the too wide welding seam needs to be polished under the condition of not damaging a base material, the width of the welding seam is generally that 3 +/-1 mm is added on two sides of a groove respectively, if other defects which are not listed in the welding process are based on the ISO 5817B grade, the requirement of butt welding seam is not lower than base material, and the residual height should not exceed 10% of welding seam width, and maximum is not more than 3mm, if the welding seam residual height is higher, it is required that two sides of welding seam should be formed smooth transition or be treated according to the technical specification requirement, the dynamic load should be selected to weaken welding seam, the static load is allowed to be selected to strengthen welding seam, but the residual height is not more than 3mm, the welding feet are symmetrical welding feet when no special description is given, and the long angle edge of the throat with the long edge being less than or equal to 1.5mm plus 15 percent is accepted;
s3: and (3) completing welding: and after welding, the welding points need to be checked and cleaned and corresponding measures are taken, and after welding, the welding points need to be checked and cleaned.
Example two
Referring to fig. 1-11, a submerged arc welding operation and method includes the steps of:
s1: preparation of the process: the method comprises the following steps of preprocessing equipment, tools and welding raw materials required by welding before welding, wherein the required equipment comprises an automatic submerged arc welding machine, a cantilever crane vehicle, a control box, a trolley walking turntable and a roller frame, an explosion-proof infrared camera, an interphone, a welding flux recycling box and a welding flux oven, the required tools comprise a wire cutter, a chisel or a cold pump gun, a hammer, a brush, a file and a sieve, the required raw materials comprise carbon steel and low alloy steel, a worker enters a welding workshop and wears a working garment and safety shoes, the PPE requirement is that the worker enters the workshop and wears a protective earplug, protective glasses, a dust mask, protective gloves and safety helmets, the preprocessing of the welding materials comprises the steps of carrying out degreasing, oxide skin, iron and moisture operations on a welding groove and the welding groove edge within 150mm, and the ratio of the width to the depth of the root cleaning groove is larger than 1: 1, degreasing by adopting a fire drying method, polishing by using a steel wire ball during deoxidation until an unoxidized part of a groove is exposed, derusting by adopting a grinding wheel brush, single-piece sand blasting and acid washing, derusting, deoxidation and degreasing the welding wire during coiling of the welding wire, wherein a rust part of the welding wire is wiped by adopting a diluted sulfuric acid solution to remove rust on the welding wire, the welding wire is subjected to deoxidation by adopting a high-temperature antioxidant, the welding wire is manually wiped to remove oil stain, a welding flux is dried in advance, the baking temperature and the time of the welding flux are carried out according to TT1-WI-TQ-040 welding material quality management regulation, and meanwhile, whether welding equipment and welding materials meet requirements and the power supply performance of newly-installed equipment are checked, and gouging oxidized slag in the groove is thoroughly cleaned before welding;
s2: and (3) welding: operating a welding machine to weld and monitor in real time, paying attention to the residual amount of the welding flux and supplementing the welding flux in time, installing a welding arc striking and extinguishing plate for longitudinal seam welding, cleaning carbon planer metal slag and welding after the arc striking and extinguishing plate is planed into a groove, cutting the arc striking and extinguishing plate after welding is finished, cutting the arc striking and extinguishing plate without damaging the base metal when the arc striking and extinguishing plate is cut, conforming to the requirements in WPS for welding materials, wherein the position of the welding materials is generally on the back of a first welding seam and is more than 50mm, the thickness of welding meat is 2-4mm, the welding seam forming is kept flat when the welding seam is divided, simultaneously, the welding machine is preheated before welding, the preheating standard is strictly executed according to WPS or procedure instruction PWI, when the assembly is carried out, the precise assembly is carried out to prevent incomplete fusion of the root caused by serious edge dislocation, if the welding current is increased, the arc voltage is correspondingly increased, the arc voltage is low when the root welding seam is carried out, the welding speed is high, if the welding speed is too low, crystal grains are coarse, the mechanical property of the welding seam is easy to reduce, the welding current avoids difficult undercut and slag removal according to requirements, if the root fusion depth is ensured, the current is slightly large but cannot exceed the upper limit of the welding parameters of field project products, the submerged arc welding is short circuit arc starting, the higher the no-load voltage of a welding machine is, the larger the short circuit current is, the easier the arc starting is, but the too high current (when the voltage is too low) often causes small forming coefficient (the fusion width is larger than the fusion depth), cracks are easy to generate, if a groove is wider in the welding process, the same layer adopts multi-pass welding, the overlapping amount between two welding passes is 1/3-1/2 with the fusion width, and the welding wire head is ground into a thinner shape by a steel wire clamp grinder to facilitate the arc starting, the contact tightness of a welding wire and a workpiece is suitable, the welding wire can be easily scratched as a standard, backing welding, tack welding or previous defects can be cleaned up to carry out next welding, the position of the welding wire is accurate, wherein the smaller the diameter of the workpiece is, the larger the requirement of an offset value b is, the smaller the value b is, the deviation value is 40-80mm, a rotary table is started firstly during circular welding to enable the welding wire to be wiped with the workpiece, then power is turned on to start arc, in addition, when submerged arc welding is carried out, a welding machine control circuit stops wire feeding firstly and then powers off, a longitudinal welding line is subjected to arc blowout on an arc blowout plate, arc pits are completely arranged outside the workpiece, the length is 70-100mm, the arc blowout starting position of the circular welding line is positioned within 300-500mm of the intersection of the longitudinal and circular welding lines, the length of an arc blowout overlapping area is not less than 50mm, if arc starting and blowout in other areas are required to be marked in time, before welding a next welding line, dregs on the previous welding line are cleaned up, the used welding flux is executed according to TT1-WI-TQ-040 welding material quality management regulation, the welding process is not allowed to undercut in principle, if undercut occurs, the local undercut depth of the cover surface and the root of the undercut is controlled within 0.25mm, meanwhile, the residual quantity of the welding flux needs to be noticed all the time during welding, filling needs to be carried out timely when the welding flux is insufficient, and the supplement specification needs to be kept consistent, an explosion-proof infrared camera is arranged at the welding position inside a welding machine during the welding process for real-time monitoring, the camera shooting content is examined in real time by a human operator in a background, the manual examination range comprises whether a welding piece group is accurate and whether a welding error occurs during the welding process, if the group is found to have serious misalignment or the welding error, the error condition needs to be reported and stated to workers in the welding workshop through an interphone immediately, the workers adjust the welding flux by the workers, if the overflow phenomenon occurs, judging by background manual work and reporting the judgment result to workers in a workshop, the workers in the workshop work according to the judgment result, wherein if the welding seam is not welded thoroughly, the welding seam needs to be ground and then re-welded, if cracks appear in the welding seam, repair welding needs to be eradicated regardless of the cracks, if pores appear on the surface, repair welding needs to be performed, if pores appear in the interior, repair welding needs to be performed according to the requirement of welding seam quality grade, if slag inclusion occurs, small slag inclusion is processed according to the pores, strip slag inclusion is determined according to the requirement of ISO 5817B grade, if the welding seam is too wide, the too wide welding seam needs to be ground under the condition of not damaging the base metal, the width of the welding seam is generally 3 +/-1 mm respectively added on two sides of a groove, if other defects which are not listed in the welding process are based on ISO 5817B grade, the requirement of butt welding seam is not lower than the base metal, the residual height does not exceed 10% of the width of the welding seam, the maximum is not greater than 3mm, and if the residual height of the welding seam is higher, two sides of the welding seam are required to form smooth transition or be treated according to the technical specification requirements, the dynamic load is preferably selected to weaken the welding seam, the static load is allowed to select a reinforced welding seam, but the residual height is not more than 3mm, the welding seam is symmetrical fillets without special description, and the long angle edge of the welding throat with the long edge being less than or equal to 1.5mm and 15 percent is accepted;
s3: and (3) completing welding: the welding joint is inspected and cleaned and corresponding measures are taken after welding is completed, the welding joint is inspected and cleaned after welding is completed, the appearance of the welding joint is inspected through visual inspection, if undercut occurs, welding beading, surface air holes and other parts which do not meet quality requirements are subjected to repair welding, surface cracks are inspected through visual inspection by using a magnifying lens not less than 6 times, magnetic powder and permeation, internal defects are inspected by using an ultrasonic method, and meanwhile, a misalignment area is thoroughly cleaned during inner-side back chipping.
EXAMPLE III
Referring to fig. 1-11, a submerged arc welding operation and method includes the steps of:
s1: preparation of the process: the method comprises the following steps of preprocessing equipment, tools and welding raw materials required by welding before welding, wherein the required equipment comprises an automatic submerged arc welding machine, an arm frame vehicle, a control box, a trolley walking turntable, a roller frame, a welding flux recycling box and a welding flux oven, the required tools comprise a wire cutter, a chisel or a cold pump gun, a hammer, a brush, a file and a sieve, the required raw materials comprise carbon steel and low alloy steel, a worker enters a welding workshop and wears a protective earplug, protective glasses, a dust mask, a protective glove and a safety helmet, the worker must meet PPE requirements when entering the welding workshop, the PPE requirements are that the worker must wear a work clothes and safety shoes when entering the workshop, the worker wears the protective earplug, the protective glasses, the dust mask, the protective glove and the safety helmet, the preprocessing of the welding materials is to carry out degreasing, oxide skin, rust and moisture operations on a welding groove and the welding groove edge within the range of 150mm, and the ratio of the width to the depth of the root-removing groove is more than 1: 1, degreasing by adopting a fire drying method, polishing by using a steel wire ball during deoxidation until an unoxidized part of a groove is exposed, derusting by adopting a grinding wheel brush, single-piece sand blasting and acid washing, derusting, deoxidation and degreasing the welding wire during coiling of the welding wire, wherein a rust part of the welding wire is wiped by adopting a diluted sulfuric acid solution to remove rust on the welding wire, the welding wire is subjected to deoxidation by adopting a high-temperature antioxidant, the welding wire is manually wiped to remove oil stain, a welding flux is dried in advance, the baking temperature and the time of the welding flux are carried out according to TT1-WI-TQ-040 welding material quality management regulation, and meanwhile, whether welding equipment and welding materials meet requirements and the power supply performance of newly-installed equipment are checked, and gouging oxidized slag in the groove is thoroughly cleaned before welding;
s2: and (3) welding: operating a welding machine to weld and monitor in real time, paying attention to the residual amount of the welding flux and supplementing the welding flux in time, installing a welding arc striking and extinguishing plate for longitudinal seam welding, cleaning carbon planer metal slag and welding after the arc striking and extinguishing plate is planed into a groove, cutting the arc striking and extinguishing plate after welding is finished, cutting the arc striking and extinguishing plate without damaging the base metal when the arc striking and extinguishing plate is cut, conforming to the requirements in WPS for welding materials, wherein the position of the welding materials is generally on the back of a first welding seam and is more than 50mm, the thickness of welding meat is 2-4mm, the welding seam forming is kept flat when the welding seam is divided, simultaneously, the welding machine is preheated before welding, the preheating standard is strictly executed according to WPS or procedure instruction PWI, when the assembly is carried out, the precise assembly is carried out to prevent incomplete fusion of the root caused by serious edge dislocation, if the welding current is increased, the arc voltage is correspondingly increased, the arc voltage is low when the root welding seam is carried out, the welding speed is high, if the welding speed is too low, crystal grains are coarse, the mechanical property of the welding seam is easy to reduce, the welding current avoids difficult undercut and slag removal according to requirements, if the root fusion depth is ensured, the current is slightly large but cannot exceed the upper limit of the welding parameters of field project products, the submerged arc welding is short circuit arc starting, the higher the no-load voltage of a welding machine is, the larger the short circuit current is, the easier the arc starting is, but the too high current (when the voltage is too low) often causes small forming coefficient (the fusion width is larger than the fusion depth), cracks are easy to generate, if a groove is wider in the welding process, the same layer adopts multi-pass welding, the overlapping amount between two welding passes is 1/3-1/2 with the fusion width, and the welding wire head is ground into a thinner shape by a steel wire clamp grinder to facilitate the arc starting, the contact tightness of a welding wire and a workpiece is suitable, the welding wire can be easily scratched as a standard, backing welding, tack welding or previous defects can be cleaned up to carry out next welding, the position of the welding wire is accurate, wherein the smaller the diameter of the workpiece is, the larger the requirement of an offset value b is, the smaller the value b is, the deviation value is 40-80mm, a rotary table is started firstly during circular welding to enable the welding wire to be wiped with the workpiece, then power is turned on to start arc, in addition, when submerged arc welding is carried out, a welding machine control circuit stops wire feeding firstly and then powers off, a longitudinal welding line is subjected to arc blowout on an arc blowout plate, arc pits are completely arranged outside the workpiece, the length is 70-100mm, the arc blowout starting position of the circular welding line is positioned within 300-500mm of the intersection of the longitudinal and circular welding lines, the length of an arc blowout overlapping area is not less than 50mm, if arc starting and blowout in other areas are required to be marked in time, before welding a next welding line, dregs on the previous welding line are cleaned up, the used welding flux is executed according to TT1-WI-TQ-040 welding material quality management regulation, the welding process is not allowed to undercut in principle, if undercut occurs, the cover surface and the local undercut depth of the root portion of the undercut should be controlled within 0.25mm, meanwhile, the residual quantity of the welding flux needs to be noticed constantly during welding, when the welding flux is insufficient, timely filling is needed, the supplement specification needs to be kept consistent, if a welding seam is too wide, the too wide welding seam needs to be ground under the condition that a base material is not damaged, the width of the welding seam is generally 3 +/-1 mm on two sides of a groove, if other defects which are not listed in the welding process are based on ISO 5817B grade, the requirement of butt welding seam is not lower than the base material, the residual height should not exceed 10% of the width of the welding seam, the maximum is not more than 3mm, if the residual height of the welding seam is higher, the two sides of the welding seam are required to be formed in smooth transition or processed according to the technical specification requirement, weakening weld joints are preferably selected for dynamic load, strengthening weld joints are allowed to be selected for static load, the rest height is not more than 3mm, symmetrical weld legs are adopted when no special description is provided, and long-angle edges of the throat with the long edge being less than or equal to 1.5mm and 15 percent are accepted;
s3: and (3) completing welding: the welding joint is inspected and cleaned and corresponding measures are taken after welding is completed, the welding joint is inspected and cleaned after welding is completed, the appearance of the welding joint is inspected through visual inspection, if undercut occurs, welding beading, surface air holes and other parts which do not meet quality requirements are subjected to repair welding, surface cracks are inspected through visual inspection by using a magnifying lens not less than 6 times, magnetic powder and permeation, internal defects are inspected by using an ultrasonic method, and meanwhile, a misalignment area is thoroughly cleaned during inner-side back chipping.
Reference standard:
welding parameters of field project products:
the reason for generating the common defects of submerged arc welding and the control method thereof are as follows:
the safety technology comprises the following steps:
(1) the welding machine shell must be well grounded (or zero protection), and the technical requirement of grounding is in accordance with the national safety technical regulation;
(2) the secondary voltage of the welding machine is a low voltage, but is higher than the safe voltage, so that when the contactor is closed, the human body is strictly prohibited from being in contact with the contact nozzle and the workpiece at the same time;
(3) when an electric appliance fails, an electrician must repair the electric appliance after cutting off the power supply;
(4) all electrical conductors should be insulated and inspected frequently, especially primary power conductors, and all wiring terminals should be protected. The cable used must meet the capacity of the rated current of the welder;
(5) the welder must wear labor protection articles, and scald is prevented when slag is removed;
(6) during the melting process of the submerged arc welding wire and during filling, cleaning and flux recovery, various smoke can be generated to stimulate respiratory organs, and a dust collection device is required to be installed in a conditioned place;
(7) when the wire feeder and the welding machine are adjusted to work, hands cannot touch the roller of the wire feeder.
The submerged arc welding procedure and method of the first, second and third examples were tested and the results were as follows:
| example one | Example two | EXAMPLE III | Existing methods | |
| Productivity of production | 80％ | 85％ | 75％ | 60％ |
The submerged arc welding method of the first embodiment, the second embodiment and the third embodiment has a remarkably improved productivity compared with the existing method, and the second embodiment is the best embodiment.
The above description is only for the preferred embodiment of the present invention, but the scope of the present invention is not limited thereto, and any person skilled in the art should be considered to be within the technical scope of the present invention, and the technical solutions and the inventive concepts thereof according to the present invention should be equivalent or changed within the scope of the present invention.
Claims (10)
1. A submerged arc welding procedure and method, characterized in that it comprises the following steps:
s1: preparation of the process: preprocessing equipment, tools and welding raw materials required by welding before welding;
s2: and (3) welding: operating a welding machine to weld and monitoring in real time, paying attention to the residual flux and supplementing the flux in time;
s3: and (3) completing welding: and after welding, the welding points need to be checked and cleaned, and corresponding measures need to be taken.
2. The submerged arc welding process and method according to claim 1, wherein in S1, the required equipment is an automatic submerged arc welding machine, a cantilever crane, a control box, a trolley walking turntable and roller frame, an explosion-proof infrared camera, an interphone, a flux recycling box and a flux oven;
the required tools are wire cutters, chisels or cold pump guns, hammers, brushes, files and sieves;
the required raw materials are carbon steel and low alloy steel, and the wearing of workers entering a welding workshop must meet PPE requirements, wherein the PPE requirements are that the workers must wear working clothes and safety shoes when entering the workshop, and wear protective earplugs, protective glasses, dust masks, protective gloves and safety helmets.
3. The submerged arc welding process and method according to claim 1, characterized in that the pre-treatment of the welding material in S1 is degreasing, scaling, rust, moisture operation within 150mm of the welding groove and its edge, and the ratio of the width to depth of the back gouging groove is more than 1: the method comprises the following steps of 1, deoiling by adopting a fire drying method, polishing by using a steel wire ball during deoxidation until a groove exposes out of an unoxidized part, derusting by adopting a grinding wheel brush, single-piece sand blasting and acid washing, derusting, deoxidation and deoiling the welding wire during coiling of the welding wire, wherein a diluted sulfuric acid solution is adopted to wipe a rust part of the welding wire to remove rust on the welding wire, a high-temperature antioxidant is adopted to remove the oxidation, the welding wire is manually wiped to remove oil stains, a welding flux is dried in advance, the baking temperature and the time of the welding flux are executed according to the quality management regulation of the welding material, meanwhile, the polarity of a power supply of the welding equipment, the welding material and a new installation equipment is checked, and gouging oxidized slag in the groove is thoroughly cleaned before welding.
4. A submerged arc welding procedure and method according to claim 1, in S2, the arc striking and extinguishing plates are welded on the longitudinal seams, the arc striking and extinguishing plate materials, the thickness and the groove size are the same as those of the base metal, the size is not less than 80 x 150mm, the length of the arc striking and extinguishing welding seam is within the range of 80mm-100mm, after the arc striking and extinguishing plates are grooved, cleaning the carbon plane metal slag and then welding, cutting the arc striking and extinguishing plate after welding, preventing the base metal from being damaged when cutting the arc striking and extinguishing plate, ensuring that the welding material used for positioning welding meets the requirement, the welding material is positioned on the back of the first welding seam, the length is more than 50mm, the thickness of the welding meat is 2-4mm, the welding seam is kept to be flat during the separation, a space is left for the next electric arc, and meanwhile, a welding machine is preheated before welding, the preheating standard is strictly executed according to a procedure operation instruction, and accurate assembly is carried out during assembly to prevent incomplete fusion of the root due to misalignment.
5. The process of claim 1, wherein in step S2, the welding current is increased, the arc voltage is increased, and when the root weld is made, the arc voltage is decreased, the welding speed is increased, and the current is increased for the penetration of the root, but the upper limit of the current in the welding parameters of the field project product is not selected.
6. The submerged arc welding operation steps and the method as claimed in claim 1, characterized in that in S2, the groove is wide during welding, multiple welding passes are adopted in the same layer, the overlapping amount between two welding passes is 1/3-1/2 of the weld width, the welding wire head is ground into a thin shape by using the sharp corner of a steel wire clamp to facilitate arc starting, backing welding, tack welding or the front pass defect needs to be cleaned up to carry out the next welding, the welding wire position is accurate, wherein the smaller the diameter of the workpiece, the larger the deviation value b is required, the smaller the value b is, the deviation amount is 40-80mm, the rotary table is started to enable the welding wire to be in sliding friction with the workpiece during girth welding, then the arc starting is conducted, and when arc is received by submerged arc welding, the control circuit of the welding machine stops feeding the welding wire at first, then cuts off the power, the longitudinal welding line stops arc on the arc extinguishing plate, the arc extinguishing pit is completely outside the workpiece, and the length is 70-100mm, the starting and extinguishing positions of the circular seams are located in a range of 300-500mm of the cross point of the longitudinal and circular seam crossing part, the length of the arc extinguishing overlapping area is not less than 50mm, if the starting and extinguishing of the arc in other parts must be marked in time, before the next welding seam is welded, the dregs on the welding seam in the previous welding seam are cleaned, and the used welding flux is executed according to the quality management regulation of welding materials.
7. The submerged arc welding process of claim 1, wherein in step S2, the welding process does not allow undercut, and the depth of partial undercut of the cap surface and the root of the undercut is controlled within 0.25 mm.
8. The submerged arc welding operation steps and the method according to claim 1, characterized in that in S2, an explosion-proof infrared camera is installed at the welding position inside the welding machine for real-time monitoring during welding, the camera content is manually checked in real time in the background, the manual checking range includes whether the assembly of welding pieces is accurate and whether welding errors occur during welding, the error condition of assembly misalignment and welding errors needs to be reported and stated to workers in a welding workshop through an interphone immediately, the workers adjust the welding pieces to generate overflow phenomenon, the background manual judges the welding pieces and reports the judgment result to the workers in the workshop, the workers in the workshop work according to the judgment result, wherein the welding pieces are not completely welded, the welding pieces need to be ground, cracks occur in the welding lines, repair welding needs to be eliminated regardless of cracks, and pores appear on the surfaces, whether repair welding is needed or not is determined according to the quality grade requirement of the welding line when air holes appear inside, small slag inclusion is processed according to the air holes when slag inclusion occurs, long-strip slag inclusion is determined according to the ISO 5817B grade requirement, the welding line is too wide, the too wide welding line needs to be polished under the condition that base metal is not damaged, the width of the welding line is 3 +/-1 mm added to two sides of a groove, and other defects which are not listed in the welding process are subject to the ISO 5817B grade.
9. The submerged arc welding operation steps and the method as claimed in claim 1, characterized in that in S2, butt weld is not lower than base metal, and the height of the butt weld is not more than 10% of the width of the butt weld, and not more than 3mm at most, and it is required that the two sides of the butt weld are smoothly excessive or processed according to the technical specification, the dynamic load should be selected to weaken the butt weld, the static load should be selected to strengthen the butt weld, but the height of the butt weld is not more than 3mm, and the butt weld is symmetrical fillet without special description, and the long side is the long angle side of the throat with the length of not more than 1.5mm + 15%.
10. A submerged arc welding procedure and method according to claim 1, characterized in that in S3, after welding, the welded joint is inspected and cleaned, the appearance of the welded joint is inspected by visual inspection, undercuts, flashes, surface blowholes and other unqualified parts are repaired, surface cracks are inspected by visual inspection with a magnifying glass of 6 times or more, magnetic powder and penetration, internal defects are inspected by ultrasonic method, and the wrong edge area is cleaned completely when inner side is cleaned.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110906853.1A CN113560701A (en) | 2021-08-09 | 2021-08-09 | Submerged arc welding operation step and method |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110906853.1A CN113560701A (en) | 2021-08-09 | 2021-08-09 | Submerged arc welding operation step and method |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN113560701A true CN113560701A (en) | 2021-10-29 |
Family
ID=78170865
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202110906853.1A Pending CN113560701A (en) | 2021-08-09 | 2021-08-09 | Submerged arc welding operation step and method |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN113560701A (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114799433A (en) * | 2022-06-01 | 2022-07-29 | 安徽精工钢结构有限公司 | Welding method for semi-automatic submerged arc welding in full penetration of thick plate |
| CN115302053A (en) * | 2022-08-29 | 2022-11-08 | 中建安装集团有限公司 | Intelligent submerged-arc welding method for stainless steel composite plate |
| CN117840590A (en) * | 2024-03-07 | 2024-04-09 | 成都天成电科科技有限公司 | Method for protecting inner cavity chip during laser re-welding and laser re-welding system |
Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2011134199A1 (en) * | 2010-04-30 | 2011-11-03 | 唐山轨道客车有限责任公司 | Welding groove joining method, double-wire welding method and system thereof |
| CN102500891A (en) * | 2011-11-08 | 2012-06-20 | 陈建平 | Welding device for large-sized vertical oil storage tank and method thereof |
| CN104977305A (en) * | 2015-06-29 | 2015-10-14 | 华中科技大学 | Welding quality analysis device based on infrared vision and analysis method thereof |
| CN105750711A (en) * | 2014-12-13 | 2016-07-13 | 重庆霸腾机械有限公司 | Q390 steel flat plate submerged-arc welding process |
| CN109834373A (en) * | 2017-11-28 | 2019-06-04 | 史和生 | A kind of view-based access control model and the automation submerged arc soldering equipment of laser tracking |
| CN211192440U (en) * | 2019-08-29 | 2020-08-07 | 安徽中联绿建钢构科技有限公司 | Automatic adjusting device for submerged-arc welding |
-
2021
- 2021-08-09 CN CN202110906853.1A patent/CN113560701A/en active Pending
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2011134199A1 (en) * | 2010-04-30 | 2011-11-03 | 唐山轨道客车有限责任公司 | Welding groove joining method, double-wire welding method and system thereof |
| CN102500891A (en) * | 2011-11-08 | 2012-06-20 | 陈建平 | Welding device for large-sized vertical oil storage tank and method thereof |
| CN105750711A (en) * | 2014-12-13 | 2016-07-13 | 重庆霸腾机械有限公司 | Q390 steel flat plate submerged-arc welding process |
| CN104977305A (en) * | 2015-06-29 | 2015-10-14 | 华中科技大学 | Welding quality analysis device based on infrared vision and analysis method thereof |
| CN109834373A (en) * | 2017-11-28 | 2019-06-04 | 史和生 | A kind of view-based access control model and the automation submerged arc soldering equipment of laser tracking |
| CN211192440U (en) * | 2019-08-29 | 2020-08-07 | 安徽中联绿建钢构科技有限公司 | Automatic adjusting device for submerged-arc welding |
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114799433A (en) * | 2022-06-01 | 2022-07-29 | 安徽精工钢结构有限公司 | Welding method for semi-automatic submerged arc welding in full penetration of thick plate |
| CN114799433B (en) * | 2022-06-01 | 2023-10-10 | 安徽精工钢结构有限公司 | Welding method of semiautomatic submerged arc welding in full penetration of thick plate |
| CN115302053A (en) * | 2022-08-29 | 2022-11-08 | 中建安装集团有限公司 | Intelligent submerged-arc welding method for stainless steel composite plate |
| CN115302053B (en) * | 2022-08-29 | 2023-11-14 | 中建安装集团有限公司 | Intelligent submerged arc welding method for stainless steel composite plate |
| CN117840590A (en) * | 2024-03-07 | 2024-04-09 | 成都天成电科科技有限公司 | Method for protecting inner cavity chip during laser re-welding and laser re-welding system |
| CN117840590B (en) * | 2024-03-07 | 2024-06-04 | 成都天成电科科技有限公司 | Method for protecting inner cavity chip during laser re-welding and laser re-welding system |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN113560701A (en) | Submerged arc welding operation step and method | |
| CN101543926B (en) | Overlaying welding technology of ductile cast iron roller | |
| CN100463767C (en) | Hydraulic turbine rotary wheel palm axle head defect handling method | |
| CN105081528A (en) | Welding technology of Q345qE structural steel | |
| CN104786003A (en) | Method for repairing main bearing hole of body | |
| CN103084703A (en) | Method for patching, overlay welding and reproducing large-scale hollow steel casting | |
| CN103962791A (en) | Welding repair method for large-sized heat-resistant steel castings | |
| CN106088572B (en) | Construction method is transformed and is used in turn to aluminum alloy mould plate | |
| CN103212913A (en) | Fitting up and welding method of major-diameter thin-wall stainless steel bellows | |
| CN103785924A (en) | Method for bead welding repair of high manganese steel cast steel frog and steel rail | |
| CN104646803B (en) | Low alloy steel plate and the welding method of ship plate | |
| CN105081683A (en) | Machining technology of straight-seam steel reel pipe | |
| CN105855786A (en) | Method for repairing welding defects of ultra-thick-wall pipe | |
| CN102848057A (en) | Method for reworking welding seam of aluminum and aluminum alloy | |
| CN101695783B (en) | Automatic control welding process for scaffold short steel pipes for construction | |
| CN112496667A (en) | Special rod guide plate surfacing repair process | |
| CN105983761A (en) | High-strength steel welding process | |
| CN102350574A (en) | Argon arc welding double-gun butt-welding method | |
| CN104588848A (en) | Consumable electrode mixed gas shielded arc welding process for steel plate with thickness being 5 mm | |
| CN104588847A (en) | Consumable electrode mixed gas shielded arc welding process for steel plate with thickness being 8-12 mm | |
| CN112008195A (en) | Research and development of construction process for controlling welding cracks of composite board | |
| CN112743292A (en) | Argon arc brazing repair method for cast iron part | |
| CN105171228A (en) | Welding technology method of motor train unit coupler seat assembly | |
| CN102642121A (en) | Cast steel stator pressing ring repair welding process | |
| CN219818343U (en) | Online welding device for cracks of large ball mill cylinder |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| RJ01 | Rejection of invention patent application after publication |
Application publication date: 20211029 |
|
| RJ01 | Rejection of invention patent application after publication |