CN118060719A - Boiler dissimilar steel tube welding method based on handheld single-mode scanning laser - Google Patents
Boiler dissimilar steel tube welding method based on handheld single-mode scanning laser Download PDFInfo
- Publication number
- CN118060719A CN118060719A CN202410075074.5A CN202410075074A CN118060719A CN 118060719 A CN118060719 A CN 118060719A CN 202410075074 A CN202410075074 A CN 202410075074A CN 118060719 A CN118060719 A CN 118060719A
- Authority
- CN
- China
- Prior art keywords
- welding
- steel pipe
- welded
- laser
- scanning
- 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
- 238000003466 welding Methods 0.000 title claims abstract description 143
- 229910000831 Steel Inorganic materials 0.000 title claims abstract description 103
- 239000010959 steel Substances 0.000 title claims abstract description 103
- 238000000034 method Methods 0.000 title claims abstract description 28
- 238000004140 cleaning Methods 0.000 claims abstract description 21
- 239000011261 inert gas Substances 0.000 claims abstract description 16
- 229910000859 α-Fe Inorganic materials 0.000 claims abstract description 13
- ATJFFYVFTNAWJD-UHFFFAOYSA-N Tin Chemical compound [Sn] ATJFFYVFTNAWJD-UHFFFAOYSA-N 0.000 claims abstract description 5
- 238000001816 cooling Methods 0.000 claims abstract description 5
- 238000007789 sealing Methods 0.000 claims abstract description 5
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 claims description 14
- 229910052757 nitrogen Inorganic materials 0.000 claims description 7
- 238000004364 calculation method Methods 0.000 claims description 4
- 239000000463 material Substances 0.000 claims description 3
- 230000007547 defect Effects 0.000 abstract description 7
- 239000013078 crystal Substances 0.000 description 7
- 238000005204 segregation Methods 0.000 description 4
- 230000015572 biosynthetic process Effects 0.000 description 3
- 229910052799 carbon Inorganic materials 0.000 description 3
- 238000004134 energy conservation Methods 0.000 description 3
- 239000002184 metal Substances 0.000 description 3
- 230000008569 process Effects 0.000 description 3
- XKRFYHLGVUSROY-UHFFFAOYSA-N Argon Chemical compound [Ar] XKRFYHLGVUSROY-UHFFFAOYSA-N 0.000 description 2
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 2
- 229910001566 austenite Inorganic materials 0.000 description 2
- 230000009286 beneficial effect Effects 0.000 description 2
- 230000007613 environmental effect Effects 0.000 description 2
- 239000000945 filler Substances 0.000 description 2
- 238000010438 heat treatment Methods 0.000 description 2
- 238000007254 oxidation reaction Methods 0.000 description 2
- 239000001301 oxygen Substances 0.000 description 2
- 229910052760 oxygen Inorganic materials 0.000 description 2
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 1
- 230000002411 adverse Effects 0.000 description 1
- 229910052786 argon Inorganic materials 0.000 description 1
- 230000001413 cellular effect Effects 0.000 description 1
- 230000008859 change Effects 0.000 description 1
- 230000009977 dual effect Effects 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 238000011010 flushing procedure Methods 0.000 description 1
- 239000010410 layer Substances 0.000 description 1
- 230000014759 maintenance of location Effects 0.000 description 1
- 229910044991 metal oxide Inorganic materials 0.000 description 1
- 150000004706 metal oxides Chemical class 0.000 description 1
- 239000000203 mixture Substances 0.000 description 1
- 230000006911 nucleation Effects 0.000 description 1
- 238000010899 nucleation Methods 0.000 description 1
- 230000000704 physical effect Effects 0.000 description 1
- 230000001681 protective effect Effects 0.000 description 1
- 239000011241 protective layer Substances 0.000 description 1
- 230000009467 reduction Effects 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
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
- B23K26/00—Working by laser beam, e.g. welding, cutting or boring
- B23K26/20—Bonding
- B23K26/21—Bonding by welding
- B23K26/24—Seam welding
- B23K26/28—Seam welding of curved planar seams
- B23K26/282—Seam welding of curved planar seams of tube sections
-
- 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
- B23K26/00—Working by laser beam, e.g. welding, cutting or boring
- B23K26/60—Preliminary treatment
-
- 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
- B23K2101/00—Articles made by soldering, welding or cutting
- B23K2101/04—Tubular or hollow articles
- B23K2101/06—Tubes
Landscapes
- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Physics & Mathematics (AREA)
- Optics & Photonics (AREA)
- Plasma & Fusion (AREA)
- Laser Beam Processing (AREA)
Abstract
The invention discloses a method for welding boiler heterogeneous steel pipes based on hand-held single-mode scanning laser, which is implemented according to the following steps: designing and processing a steel pipe groove according to the diameter of the welding wire, and cleaning the side wall of the groove; after the steel pipe is fixed by a clamp and a spot welding mode, sealing two ends of the steel pipe by tinfoil and introducing inert gas to obtain a steel pipe to be welded; carrying out multistage scanning preheating on a steel pipe to be welded through laser beams emitted by single-mode scanning laser, determining the placement of a welding gun, controlling the rotation feeding of the steel pipe to be welded through a motor, and carrying out single-pass welding while controlling the welding speed to obtain a preform; and placing the prefabricated body in a constant temperature furnace for local constant temperature and then slowly cooling to obtain the welded boiler heterogeneous steel pipe. The invention solves the problems of air hole defect and blocky delta ferrite during welding in the prior art.
Description
Technical Field
The invention belongs to the technical field of steel pipe welding methods, and particularly relates to a boiler dissimilar steel pipe welding method based on a handheld single-mode scanning laser.
Background
With the increasing of electric power demands and the dual driving of energy conservation and emission reduction, the energy system is gradually turned to the low-carbon direction, and the welding of single metal can not well meet the requirements of green low-carbon, energy conservation, environmental protection, structural functions and the like. Based on the double consideration of economy and safety, the improved high-strength ferritic steel and austenitic heat-resistant steel are widely applied to superheater tubes and reheater tubes in supercritical units. However, the traditional arc welding or argon arc welding method is still adopted, and is limited by the size of a welding gun, so that the problems of low welding efficiency, large welding wire filling quantity and high overall heat input of a welded joint can occur when a large-angle groove is welded, and more welding defects are easy to generate.
With the rapid development of the laser welding technology at home and abroad, the handheld single-mode scanning laser welding has the advantages of obviously improving the welding efficiency, having flexible and wide application scene, effectively improving the weld formation and optimizing the weld structure, reducing the component segregation and improving the service performance of the joint.
However, in the welding method in the prior art, the improved high-strength ferrite steel and the austenitic heat-resistant steel have different chemical components, tissue structures and physical properties; during welding, the operation position of a welding gun is not optimized, so that laser and a welding wire cannot be well coupled, and air hole defects are generated; and the island structure caused by massive delta ferrite and component segregation is easy to appear because the energy is not concentrated, and the service performance of the welded joint is adversely affected.
Disclosure of Invention
The invention aims to provide a method for welding a boiler dissimilar steel tube based on a handheld single-mode scanning laser, which solves the problems that in the prior art, when welding is carried out at an operation position of a welding gun, air hole defects are generated and massive delta ferrite is generated.
The technical scheme of the invention is a method for welding the boiler dissimilar steel pipes based on the handheld single-mode scanning laser, which is implemented according to the following steps:
Step 1, designing a steel pipe groove according to the diameter of a welding wire, processing the steel pipe groove, and cleaning the side wall of the groove;
step 2, fixing the steel pipe through a clamp and a spot welding mode, sealing two ends of the steel pipe through tinfoil, and introducing inert gas to obtain a steel pipe to be welded;
Step 3, carrying out multistage scanning preheating on the steel tube to be welded in the step 2 through laser beams emitted by single-mode scanning laser, determining the placement of a welding gun, and carrying out single-pass welding while controlling the welding speed by controlling the rotation feeding of the steel tube to be welded through a motor to obtain a preform;
and 4, placing the prefabricated body in the step 3 in a constant temperature furnace for local constant temperature and then slowly cooling to obtain the welded boiler heterogeneous steel pipe.
The present invention is also characterized in that,
In the step1, the welding wire material is ferrite heat-resistant steel or austenitic heat-resistant steel pipe.
In the step 1, the thickness of the steel pipe is 2-8 mm, and the groove of the steel pipe is a Y-shaped groove; the calculation method of the Y-shaped groove is as follows
A＝0.5α+(0-0.2)(1)
B＝0.5α+(0-0.4)(2)
Wherein A is groove depth, B is groove bevel edge width, and alpha is welding wire diameter.
The specific mode for cleaning the side wall of the groove in the step 1 is as follows: the side wall of the groove is cleaned by adopting a cleaning mode of a single-mode scanning laser welding gun, the scanning frequency of laser cleaning is 100 Hz-200 Hz, the laser power range is 150W-1000W, and the scanning amplitude range is 2 mm-8 mm.
In the step2, the inert gas is nitrogen with the purity of 99.999 percent, and the pressure of the inert gas is 0.1MPa to 0.2MPa.
The step 3 is specifically implemented according to the following steps:
Step 3.1, carrying out multistage scanning preheating on the steel tube to be welded in the step 2 through laser beams emitted by single-mode scanning laser; the scanning frequency range of the laser beam is 30 Hz-200 Hz, the laser power range is 150W-1500W, the welding linear speed is 14 mm/s-26 mm/s, the wire feeding speed range is 2.0 m/min-3.2 m/min, the defocusing amount range is 0 mm-4 mm, the scanning amplitude range of the laser beam is alpha+0.2-alpha+0.4, wherein alpha is the diameter of the welding wire;
The multi-stage scanning preheating is four-stage scanning preheating, and the laser scanning welding gun scans from the initial end of the area to be welded to the junction tail end of the area to be welded at the speed of 10 mm/s-26 mm/s at the laser power of 200W, 400W and 800W respectively;
step 3.2, the horizontal included angle beta between the center of the laser beam and the contact point of the steel pipe to be welded is 30-60 degrees, and the included angle theta between the placing position of the welding gun and the center horizontal line of the steel pipe to be welded is 30-70 degrees from the clockwise rotation direction of the sample; and determining the position of the welding gun.
And 3.3, controlling the rotation feeding of the steel pipe to be welded through a motor, and performing single-pass welding while controlling the welding speed to obtain the preform.
In the step 4, the local constant temperature range is 740-760 ℃, and the local constant temperature treatment time is 1-1.5 h.
The beneficial effects of the invention are as follows:
(1) The welding method of the invention ensures that the laser light source is firstly scanned when scanning the laser filler wire for welding, the cleaning of the side wall of the groove and the preheating before welding are completed, the stress concentration condition of the welding joint can be effectively reduced by the preheating before welding, and the whole heat input is reduced;
(2) Compared with multimode lasers, the single-mode lasers have more concentrated energy, smaller heat affected zone of the welding joint, short duration of the peak temperature of the welding heat cycle and no blocky delta ferrite at the joint;
(3) According to the invention, the preferential growth direction of the weld joint columnar crystals is changed due to the continuous change of the temperature gradient in the molten pool, so that the diversity of grain orientations is increased, the convection effect of the molten pool is enhanced, the growing columnar crystals are broken by flushing the grains, new nucleation points are formed, and the formation of equiaxed crystals is promoted; the scanning of the laser promotes the flow of a molten pool, avoids the formation of a retention layer, and reduces the component segregation;
(4) According to the invention, the stability of the welding process can be maintained by optimizing the operation position of the welding gun, so that the laser and the welding wire can be well coupled, the occurrence of defects such as air holes and the like is reduced, the hardness gradient of the welded joint on one side of the ferrite heat-resistant steel is reduced by the local heat treatment after welding, and the stress concentration is reduced.
Drawings
FIG. 1 is a flow chart of a method for welding dissimilar steel tubes of a boiler based on a handheld single-mode scanning laser of the present invention;
FIG. 2 is a schematic view of a groove in the welding method of the present invention;
FIG. 3 is a schematic view of the position of a welding gun in the welding method of the present invention;
FIG. 4 is a microstructure view of the weld center of a welded joint in the welding method of the present invention;
FIG. 5 is a microstructure view of a weld line of a side joint in example 1 of the welding method of the present invention;
FIG. 6 is a microstructure view of the weld line of the other side joint in example 1 of the welding method of the present invention.
Detailed Description
The invention will be described in detail below with reference to the drawings and the detailed description.
The invention provides a method for welding boiler dissimilar steel pipes based on hand-held single-mode scanning laser, which is implemented according to the following steps as shown in fig. 1:
Step 1, designing a steel pipe groove according to the diameter of a welding wire, processing the steel pipe groove, and cleaning the side wall of the groove;
In the step 1, the welding wire is made of ferrite heat-resistant steel or austenite heat-resistant steel pipe, the welding of single metal can not well meet the requirements of green low carbon, energy conservation, environmental protection and structural function, and the improved high-strength ferrite steel and the austenite heat-resistant steel are selected based on the double consideration of economy and safety.
As shown in fig. 2, the thickness of the steel pipe in the step 1 is 2 mm-8 mm, and the groove of the steel pipe is a Y-shaped groove; the calculation method of the Y-shaped groove is as follows
A＝0.5α+(0-0.2)(1)
B＝0.5α+(0-0.4)(2)
Wherein A is groove depth, B is groove bevel edge width, and alpha is welding wire diameter.
The specific mode for cleaning the side wall of the groove in the step 1 is as follows: the side wall of the groove is cleaned by adopting a cleaning mode of a single-mode scanning laser welding gun, the scanning frequency of laser cleaning is 100 Hz-200 Hz, the laser power range is 150W-1000W, and the scanning amplitude range is 2 mm-8 mm.
Step 2, fixing the steel pipe through a clamp and a spot welding mode, sealing two ends of the steel pipe through tinfoil, and introducing inert gas to obtain a steel pipe to be welded; the inert gas is nitrogen with the purity of 99.999 percent, and the pressure of the inert gas is 0.1MPa to 0.2MPa. In the welding process, the metal is easy to perform oxidation reaction with oxygen in the air to form metal oxide, so that the quality of the welding seam is reduced. The introduction of the nitrogen with the purity of 99.999% forms a protective atmosphere of the welding area, so that oxygen in the air is removed, the oxidation reaction is effectively prevented, the welding area can be wrapped by the nitrogen with the purity of 99.999%, a protective layer is formed, and the welding seam is prevented from being damaged by pollution factors in the environment such as the air. Thus, the high purity of the welding seam can be ensured, and the welding quality is improved.
Step 3, carrying out multistage scanning preheating on the steel tube to be welded in the step 2 through laser beams emitted by single-mode scanning laser, determining the placement of a welding gun, and carrying out single-pass welding while controlling the welding speed by controlling the rotation feeding of the steel tube to be welded through a motor to obtain a preform; during scanning laser filler wire welding, firstly, the groove side wall is cleaned and preheated before welding by scanning through a 1+4 laser light source. The stress concentration condition of the welded joint can be effectively reduced by preheating before welding, and the integral heat input is reduced. By optimizing the operation position of the welding gun, the stability of the welding process can be maintained, so that the laser and the welding wire can be well coupled, and the occurrence of defects such as air holes and the like is reduced.
Step 3.1, carrying out multistage scanning preheating on the steel tube to be welded in the step 2 through laser beams emitted by single-mode scanning laser; the scanning frequency range of the laser beam is 30 Hz-200 Hz, the laser power range is 150W-1500W, the welding linear speed is 14 mm/s-26 mm/s, the wire feeding speed range is 2.0 m/min-3.2 m/min, the defocusing amount range is 0 mm-4 mm, the scanning amplitude range of the laser beam is alpha+0.2-alpha+0.4, wherein alpha is the diameter of the welding wire;
The multi-stage scanning preheating is four-stage scanning preheating, and the laser scanning welding gun scans from the initial end of the area to be welded to the junction tail end of the area to be welded at the speed of 10 mm/s-26 mm/s at the laser power of 200W, 400W and 800W respectively;
as shown in fig. 3, in step 3.2, the horizontal included angle beta between the center of the laser beam and the contact point of the steel tube to be welded is 30-60 degrees, and the included angle theta between the placing position of the welding gun and the center horizontal line of the steel tube to be welded is 30-70 degrees from the clockwise rotation direction of the sample; and determining the position of the welding gun.
And 3.3, controlling the rotation feeding of the steel pipe to be welded through a motor, and performing single-pass welding while controlling the welding speed to obtain the preform.
And 4, placing the prefabricated body in the step 3 in a constant temperature furnace for local constant temperature and then slowly cooling to obtain the welded boiler heterogeneous steel pipe. The range temperature of the local constant temperature is 740-760 ℃, and the treatment time of the local constant temperature is 1-1.5 h. The post-welding local heat treatment reduces the hardness gradient of the welded joint on one side of the ferrite heat-resistant steel, and is beneficial to reducing stress concentration.
Example 1
The embodiment provides a boiler dissimilar steel tube welding method based on a handheld single-mode scanning laser, which is implemented according to the following steps:
Step 1, designing a steel pipe groove according to the diameter of a welding wire, processing the steel pipe groove, and cleaning the side wall of the groove; in the step 1, the welding wire material is ferrite heat-resistant steel or austenitic heat-resistant steel pipe. In the step 1, the thickness of the steel pipe is 2mm, and the groove of the steel pipe is a Y-shaped groove; the calculation method of the Y-shaped groove is as follows
A＝0.5α+(0-0.2)(1)
B＝0.5α+(0-0.4)(2)
Wherein A is groove depth, B is groove bevel edge width, and alpha is welding wire diameter.
The side wall of the groove is cleaned by adopting a cleaning mode of a single-mode scanning laser welding gun, the scanning frequency of laser cleaning is 100Hz, the laser power range is 150W, and the scanning amplitude range is 2mm.
Step 2, fixing the steel pipe through a clamp and a spot welding mode, sealing two ends of the steel pipe through tinfoil, and introducing inert gas to obtain a steel pipe to be welded; the inert gas is nitrogen with the purity of 99.999 percent, and the pressure of the inert gas is 0.15MPa. The clamp is a three-jaw chuck.
Step 3, carrying out multistage scanning preheating on the steel tube to be welded in the step 2 through laser beams emitted by single-mode scanning laser, determining the placement of a welding gun, and carrying out single-pass welding while controlling the welding speed by controlling the rotation feeding of the steel tube to be welded through a motor to obtain a preform;
Step 3.1, carrying out multistage scanning preheating on the steel tube to be welded in the step 2 through laser beams emitted by single-mode scanning laser; the scanning frequency range of the laser beam is 120Hz, the laser power range is 150W, the welding linear speed is 18mm/s, the wire feeding speed range is 2.2m/min, the defocusing amount range is 0mm, and the scanning amplitude range of the laser beam is alpha+0.2, wherein alpha is the diameter of the welding wire;
The multi-stage scanning preheating is four-stage scanning preheating, and a laser scanning welding gun scans from the initial end of a region to be welded to the junction tail end of the region to be welded at a speed of 22mm/s at laser powers of 200W, 400W and 800W respectively;
step 3.2, the horizontal included angle beta between the center of the laser beam and the contact point of the steel pipe to be welded is 50 degrees, and the included angle theta between the placing position of the welding gun and the center horizontal line of the steel pipe to be welded is 45 degrees from the clockwise rotation direction of the sample; and determining the position of the welding gun.
And 3.3, controlling the rotation feeding of the steel pipe to be welded through a motor, and performing single-pass welding while controlling the welding speed to obtain the preform.
And 4, placing the prefabricated body in the step 3 in a constant temperature furnace for local constant temperature and then slowly cooling to obtain the welded boiler heterogeneous steel pipe.
In the step 4, the range temperature of the local constant temperature is 740 ℃, and the treatment time of the local constant temperature is 1h.
As shown in fig. 4, the microstructure of the weld joint center of the welded joint shows a mixture of cellular crystals, columnar crystals and equiaxed crystals in the weld zone, and the columnar crystals are diversified in orientation. The welded joint has no obvious defects of air holes, undercut, cracks and the like, and the shape of the weld joint meets the standard requirements. As shown in fig. 5 and 6, the microstructure on both sides of the weld joint weld line does not show "island structure" due to delta ferrite and component segregation. The fracture result of the dissimilar steel test tube joint of the embodiment is broken at the weld joint, the tensile strength reaches 616MPa, and the requirements of related standards are met.
Example 2
The difference from example 1 is that in step 1, the thickness of the steel pipe is 5mm, the side wall of the groove is cleaned by adopting a cleaning mode of a single-mode scanning laser welding gun, the scanning frequency of laser cleaning is 150Hz, the laser power range is 550W, and the scanning range is 5mm. The inert gas is nitrogen with the purity of 99.999 percent, and the pressure of the inert gas is 0.1MPa. The scanning frequency range of the laser beam is 30Hz, the laser power range is 1000W, the welding linear speed is 14mm/s, the wire feeding speed range is 2.0m/min, the defocusing amount range is 2.5mm, and the scanning amplitude range of the laser beam is alpha+0.2-alpha+0.4, wherein alpha is the diameter of the welding wire; the laser scanning welding gun scans from the initial end of the area to be welded to the junction tail end of the area to be welded at the speed of 10mm/s with the laser power of 200W, 400W and 800W respectively; from the clockwise rotation direction of the sample, the horizontal included angle beta between the center of the laser beam and the contact point of the steel tube to be welded is 30 degrees, and the included angle theta between the placing position of the welding gun and the horizontal line of the center of the steel tube to be welded is 30 degrees; and determining the position of the welding gun. In the step 4, the range temperature of the local constant temperature is 750 ℃, and the treatment time of the local constant temperature is 1.3h.
Example 3
The difference from example 1 is that the thickness of the steel pipe in step 1 is 8mm, the side wall of the groove is cleaned by adopting a cleaning mode of a single-mode scanning laser welding gun, the scanning frequency of laser cleaning is 220Hz, the laser power range is 1000W, and the scanning amplitude range is 8mm. The pressure of the inert gas was 0.2MPa. The scanning frequency range of the laser beam is 200Hz, the laser power range is 1500W, the welding linear speed is 26mm/s, the wire feeding speed range is 3.2m/min, the defocusing amount range is 4mm, and the scanning amplitude range of the laser beam is alpha+0.2-alpha+0.4, wherein alpha is the diameter of the welding wire; the laser scanning welding gun scans from the initial end of the area to be welded to the junction tail end of the area to be welded at the speed of 26mm/s with the laser power of 200W, 400W and 800W respectively; from the clockwise rotation direction of the sample, the horizontal included angle beta between the laser beam center and the contact point of the steel pipe to be welded is 60 degrees, and the included angle theta between the welding gun placement position and the horizontal line of the center of the steel pipe to be welded is 70 degrees; and determining the position of the welding gun. The range temperature of the local constant temperature is 760 ℃, and the treatment time of the local constant temperature is 1.5h.
Claims (7)
1. The method for welding the boiler dissimilar steel tube based on the handheld single-mode scanning laser is characterized by comprising the following steps of:
Step 1, designing a steel pipe groove according to the diameter of a welding wire, processing the steel pipe groove, and cleaning the side wall of the groove;
step 2, fixing the steel pipe through a clamp and a spot welding mode, sealing two ends of the steel pipe through tinfoil, and introducing inert gas to obtain a steel pipe to be welded;
Step 3, carrying out multistage scanning preheating on the steel pipe to be welded in the step 2 through laser beams emitted by single-mode scanning laser, determining the placement of a welding gun, and carrying out single-pass welding while controlling the rotation feeding of the steel pipe to be welded through a motor to control the welding speed so as to obtain a preform;
and 4, placing the prefabricated body in the step 3 in a constant temperature furnace for local constant temperature and then slowly cooling to obtain the welded boiler heterogeneous steel pipe.
2. The method for welding dissimilar steel tubes of a boiler based on a hand-held single-mode scanning laser according to claim 1, wherein the welding wire material in step 1 is ferrite heat-resistant steel or austenitic heat-resistant steel tube.
3. The method for welding the dissimilar steel tube of the boiler based on the handheld single-mode scanning laser, which is characterized in that in the step 1, the thickness of the steel tube is 2-8 mm, and the groove of the steel tube is a Y-shaped groove; the calculation method of the Y-shaped groove is as follows
A＝0.5α+(0-0.2) (1)
B＝0.5α+(0-0.4) (2)
Wherein A is groove depth, B is groove bevel edge width, and alpha is welding wire diameter.
4. The method for welding the dissimilar steel tube of the boiler based on the handheld single-mode scanning laser according to claim 1, wherein the specific mode of cleaning the side wall of the groove in the step 1 is as follows: the side wall of the groove is cleaned by adopting a cleaning mode of a single-mode scanning laser welding gun, the scanning frequency of laser cleaning is 100 Hz-200 Hz, the laser power range is 150W-1000W, and the scanning amplitude range is 2 mm-8 mm.
5. The method for welding the dissimilar steel tube of the boiler based on the handheld single-mode scanning laser according to claim 1, wherein the inert gas in the step 2 is nitrogen with the purity of 99.999%, and the pressure of the inert gas is 0.1-0.2 MPa.
6. The method for welding the dissimilar steel tube of the boiler based on the handheld single-mode scanning laser according to claim 1, wherein the step 3 is specifically implemented according to the following steps:
Step 3.1, carrying out multistage scanning preheating on the steel tube to be welded in the step 2 through laser beams emitted by single-mode scanning laser; the scanning frequency range of the laser beam is 30 Hz-200 Hz, the laser power range is 150W-1500W, the welding linear speed is 14 mm/s-26 mm/s, the wire feeding speed range is 2.0 m/min-3.2 m/min, the defocusing amount range is 0 mm-4 mm, the scanning amplitude range of the laser beam is alpha+0.2-alpha+0.4, wherein alpha is the diameter of the welding wire;
The multi-stage scanning preheating is four-stage scanning preheating, and a laser scanning welding gun scans from the initial end of a region to be welded to the junction tail end of the region to be welded at the speed of 10 mm/s-26 mm/s at the laser power of 200W, 400W and 800W respectively;
Step 3.2, the horizontal included angle beta between the center of the laser beam and the contact point of the steel pipe to be welded is 30-60 degrees, and the included angle theta between the placing position of the welding gun and the center horizontal line of the steel pipe to be welded is 30-70 degrees from the clockwise rotation direction of the sample; determining the position of a welding gun;
And 3.3, controlling the rotation feeding of the steel pipe to be welded through a motor, and performing single-pass welding while controlling the welding speed to obtain the preform.
7. The method for welding the dissimilar steel tube of the boiler based on the handheld single-mode scanning laser according to claim 1, wherein the range temperature of the local constant temperature in the step 4 is 740-760 ℃, and the treatment time of the local constant temperature is 1-1.5 h.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202410075074.5A CN118060719A (en) | 2024-01-18 | 2024-01-18 | Boiler dissimilar steel tube welding method based on handheld single-mode scanning laser |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202410075074.5A CN118060719A (en) | 2024-01-18 | 2024-01-18 | Boiler dissimilar steel tube welding method based on handheld single-mode scanning laser |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN118060719A true CN118060719A (en) | 2024-05-24 |
Family
ID=91098051
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202410075074.5A Pending CN118060719A (en) | 2024-01-18 | 2024-01-18 | Boiler dissimilar steel tube welding method based on handheld single-mode scanning laser |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN118060719A (en) |
-
2024
- 2024-01-18 CN CN202410075074.5A patent/CN118060719A/en active Pending
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| EP2546020B1 (en) | Laser/arc hybrid welding method and method for producing welded member using same | |
| CA2691715C (en) | Method and device for connecting thick-walled metal workpieces by welding | |
| CN101733564A (en) | Laser-electric arc composite heat source high-speed welding method of ultrahigh strength steel | |
| EP0689896A1 (en) | Plasma welding process | |
| CN118060719A (en) | Boiler dissimilar steel tube welding method based on handheld single-mode scanning laser | |
| CN106735903B (en) | A kind of finned tube welding method and system | |
| CN114905151B (en) | 2219 aluminum alloy sheet electromagnetic auxiliary laser thermal conductive welding method | |
| CN114985933B (en) | Vacuum swing laser welding method for niobium alloy | |
| CN116275381A (en) | Cold arc metal transition aluminum alloy welding method for laser-induced stable arc transition | |
| CN113798632B (en) | Forming method for arc fuse additive manufacturing | |
| CN113941776B (en) | Thick plate ultrahigh-power double-beam laser-high-frequency pulse deep melting TIG (tungsten inert gas) hybrid welding method | |
| CN110560873A (en) | Vacuum electron beam welding method for stainless steel water cooling ring | |
| CN113814563B (en) | Method and device for improving corrosion resistance of MIG welding Cr-Ni series stainless steel | |
| JP2001239367A (en) | Gas shielded arc welding method | |
| CN115365658B (en) | Laser welding method and system suitable for energy space-time dynamic distribution of special-shaped joint | |
| CN111715982A (en) | Novel welding method of high-alloy austenitic heat-resistant stainless steel | |
| JP3767359B2 (en) | Butt welding method and welded thin steel plate | |
| CN110560867A (en) | Vacuum electron beam welding method for aluminum alloy water-cooled joint | |
| CN114918564B (en) | Build-up welding repair method for TC4 titanium alloy shell | |
| CN112719553B (en) | Electron beam welding method for aluminum-lithium alloy medium plate | |
| CN112743230B (en) | Method and system for laser welding of magnesium alloy | |
| CN115958296A (en) | Welding forming method for AlSi10Mg aluminum alloy structural member by selective laser melting forming | |
| CN116833555A (en) | Narrow-gap boiler dissimilar steel tube welding method based on handheld laser swing | |
| EP0824987A1 (en) | Plasma welding process | |
| SU1428557A1 (en) | Method of welding longitudinal seam of large-diameter pipes |
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 |