CN110682051A - Novel process for rolling and assembling large-taper thick plate - Google Patents
Novel process for rolling and assembling large-taper thick plate Download PDFInfo
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- CN110682051A CN110682051A CN201910778892.0A CN201910778892A CN110682051A CN 110682051 A CN110682051 A CN 110682051A CN 201910778892 A CN201910778892 A CN 201910778892A CN 110682051 A CN110682051 A CN 110682051A
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
- B23P—METAL-WORKING NOT OTHERWISE PROVIDED FOR; COMBINED OPERATIONS; UNIVERSAL MACHINE TOOLS
- B23P15/00—Making specific metal objects by operations not covered by a single other subclass or a group in this subclass
Abstract
The invention discloses a novel process for rolling and assembling a large-taper thick plate, which comprises the steps of blanking, opening, pre-bending, centering, rolling, tack welding, longitudinal seam welding, turning over and returning, longitudinal seam nondestructive testing, circular seam assembling and welding, circular seam nondestructive testing and the like. The invention adds a turning-over process, and controls the roundness of the tower barrel by using barrel section reversible deformation caused by the gravity effect; a small-opening speed reducer is adopted in the rolling process, and the moving speed of the small-opening end of the fan-shaped plate is reduced by means of friction force generated by a friction steel plate, so that the conical cylindrical shell section can be rolled.
Description
Technical Field
The invention relates to the technical field of machine manufacturing, in particular to a novel process for rolling and assembling a large-taper thick plate.
Background
With the continuous perfection of wind power basic technology, a large megawatt series tower barrel on the sea is produced, the wind power tower barrel needs to have a certain height, so that wind power can be perfectly utilized, and the shock resistance is needed, so that a conical barrel section is correspondingly generated, the vibration caused by a fan blade is reduced by the conical barrel section, and the stability of the wind power tower barrel is improved. However, the rolling of the offshore wind power conical tower cylinder has the following characteristics and difficulties: 1. the molding and the roundness of the tower barrel are ensured; 2. the misalignment amount between the shell ring and the shell ring is ensured.
Disclosure of Invention
In view of the above situation, the invention provides a new process for rolling and assembling a large-taper thick plate, and provides an effective solution for solving the above problems.
The technical scheme adopted by the invention is as follows: a new technology for rolling and assembling a large-taper thick plate specifically comprises the following steps:
1) blanking, namely blanking a fan-shaped steel plate for rolling each section of conical shell section by adopting a program-controlled numerical control flame cutting machine according to the size requirement, wherein the blanking size deviation has the length direction error of 0 ~ 1.5.5 mm, the plate width difference is less than or equal to 1.5mm, and the diagonal line difference is less than or equal to 2.5 mm.
2) Groove opening: and (4) forming a butt joint groove of the longitudinal seam and the circular seam of the plate, polishing the edge of the groove by using a polishing machine, and cleaning impurities within a range of 30mm near the groove.
3) Pre-bending: the method comprises the steps of feeding a pre-designed bending model into a space between an upper roller and a lower roller of a four-roller plate bending machine, fixing the bending model above the two side rollers by adopting a support, feeding one end of a plate to be pre-bent into the plate bending machine, placing the plate on the bending model, pressing the upper roller downwards to enable the plate to generate plastic deformation, pre-bending the other end of the plate, and pre-bending the two ends of the plate to a set curvature radius.
4) Centering: and (3) feeding the pre-bent plate into a four-roller plate bending machine, and marking the longitudinal center line of the plate by using a pencil to ensure that the generatrix of the plate is strictly parallel to the axial center line of the roller within 1mm of parallelism.
5) Rolling: a friction speed reducer is added at the feeding position of the small opening end of the plate by adopting a small opening speed reducing method, and the resistance borne by the plate is increased while the small opening end of the plate is feeding, so that an upper roller of a plate rolling machine is basically overlapped with a plain line of the plate in the rolling process of the plate.
6) Positioning welding: adjusting the distance of the butt joint by a tensioning tool, verifying the curvature radius of the rolled vertebral body by using a cylinder rolling sample plate, and repeating the pre-bending step if the process requirement is not met; spot welding positioning is carried out before formal welding, and welding parameters are as follows: setting a positioning welding spot every 300mm, wherein the length of each section of positioning welding is more than or equal to 50mm, the welding height is 3mm, carbon dioxide gas shielded welding is adopted, the welding wire adopts E501T-1, the welding current is 200A-260A, the voltage is 28V-33V, and the welding speed is 250mm/min-260 mm/min.
7) Longitudinal seam welding: firstly, carrying out submerged arc welding inside a tower shell ring, after welding to a cover surface, adopting carbon arc gouging to back off the outer side of the shell ring, polishing a carburized layer and slag after back off by using a polishing machine, then carrying out cover surface welding, monitoring UT to be qualified, and welding parameters: h10Mn2 is selected as a welding wire, SJ101 is selected as a submerged arc welding agent, 650A-740A of internal welding current, 29V-33V of voltage and 25m/H-32m/H of welding speed, 700A-750A of external welding current, 33V-36V of voltage and 25m/H-32m/H of welding speed are selected as external welding current.
8) Turning over and rounding: the conical tower cylinder section is turned over to offset micro-deformation, and is returned to the circle through three steps of loading, rounding and unloading, so that the plate is rolled to the circle of 1 to 2 circles in the correction curvature of the plate rolling machine cylinder to reach the specified curvature radius position.
9) Longitudinal seam nondestructive testing: and performing UT ultrasonic nondestructive testing on the welding seam, and repairing the welding seam with welding defects according to the process until the welding seam is qualified.
10) Assembling circular seams: assembling the circular seams of the shell ring and the shell ring in place, and connecting the bevels.
11) Girth welding: firstly, carrying out submerged-arc welding in the cylinder, welding to the cover surface, then finishing the welding on the inner side, then carrying out back gouging on the outer side of the cylinder section by adopting a carbon arc gouging machine, polishing a carburized layer and slag on the surface of the tower frame after back gouging by using a polishing machine until the surface of a welding seam is exposed with metal luster, then carrying out submerged-arc welding on the cover surface, and finishing the welding after the cover surface is welded; specific welding parameters are as follows: the welding wire H10Mn2, the flux SJ101, the current 650A-750A, the voltage 29V-33V and the welding speed 25m/H-32m/H are adopted inside, and the welding wire H10Mn2, the flux SJ101, the current 700A-750A, the voltage 33V-36V and the welding speed 25m/H-32m/H are adopted outside.
12) And (5) performing nondestructive detection on the circular seam.
Further, before the rolling process in the step (5), the surface of the plate needs to be cleaned, and oxide skin on the surface of the plate is removed; when the rolling process is carried out, the air gun is continuously used for blowing the oxide to ensure that the groove and the two sides of the groove are free of impurities within 30 mm.
The invention has the advantages that: 1. and a turning-over process is added, the roundness 2 of the tower barrel is controlled by using barrel section reversible deformation caused by the gravity effect, a small-opening speed reducer is adopted in the rolling process, and the moving speed of the small-opening end of the sector plate is reduced by the friction force generated by a friction steel plate so as to roll the conical cylindrical barrel section.
Drawings
Fig. 1 is a schematic view of a crimping structure.
Wherein: 1. an upper roller 2, a lower roller 3, a plate 4 and a speed reducing device.
Detailed Description
The present invention will be further described in detail with reference to the accompanying drawings, wherein the embodiments are implemented on the premise of the technical solution of the present invention, and detailed embodiments are provided, but the scope of the present invention is not limited to the following embodiments.
A new technology for rolling and assembling a large-taper thick plate specifically comprises the following steps:
1) blanking, namely blanking a fan-shaped steel plate for rolling each section of conical shell section by adopting a program-controlled numerical control flame cutting machine according to the size requirement, wherein the blanking size deviation has the length direction error of 0 ~ 1.5.5 mm, the plate width difference is less than or equal to 1.5mm, and the diagonal line difference is less than or equal to 2.5 mm.
2) Groove opening: and (4) forming a butt joint groove of the longitudinal seam and the circular seam of the plate, polishing the edge of the groove by using a polishing machine, and cleaning impurities within a range of 30mm near the groove.
3) Pre-bending: the method comprises the steps of feeding a pre-designed bending model into a space between an upper roller and a lower roller of a four-roller plate bending machine, fixing the bending model above the two side rollers by adopting a support, feeding one end of a plate to be pre-bent into the plate bending machine, placing the plate on the bending model, pressing the upper roller downwards to enable the plate to generate plastic deformation, pre-bending the other end of the plate, and pre-bending the two ends of the plate to a set curvature radius.
4) Centering: and (3) feeding the pre-bent plate into a four-roller plate bending machine, marking the longitudinal center line of the plate by using a stone pencil, and finely adjusting the position of the plate left and right by using a travelling crane for centering to ensure that the generatrix of the plate is strictly parallel to the axial center line of the roller and the parallelism is within 1 mm.
5) Rolling: before the rolling process, the surface of the plate needs to be cleaned, oxide skin on the surface of the plate is removed, a small-opening speed reduction method is adopted in the specific rolling step, a friction speed reduction device 4 is added at a feeding position of a small opening end of the plate 3, so that an upper roller 1 of a plate rolling machine is basically superposed with a plain line of the plate 3 in the rolling process, a lower roller 2 is parallel to the plain line of the plate 3, and the conical plate rolling process is completed; when the rolling procedure is carried out, the oxide is continuously blown by an air gun; as shown in figure 1.
6) Positioning welding: adjusting the distance between the butt joints of the cylinder sections by a tensioning tool, verifying the curvature radius of the rolled cone by using a cylinder rolling sample plate, and repeating the pre-bending step if the process requirement is not met; spot welding positioning is carried out before formal welding, and welding parameters are as follows: setting a positioning welding spot every 300mm, wherein the length of each section of positioning welding is more than or equal to 50mm, the welding height is 3mm, carbon dioxide gas shielded welding is adopted, the welding wire adopts E501T-1, the welding current is 200A-260A, the voltage is 28V-33V, and the welding speed is 250mm/min-260 mm/min.
7) Longitudinal seam welding: firstly, carrying out submerged arc welding inside a tower shell ring, after welding to a cover surface, adopting carbon arc gouging to back off the outer side of the shell ring, polishing a carburized layer and slag after back off by using a polishing machine, then carrying out cover surface welding, monitoring UT to be qualified, and welding parameters: h10Mn2 is selected as a welding wire, SJ101 is selected as a submerged arc welding agent, 650A-740A of internal welding current, 29V-33V of voltage and 25m/H-32m/H of welding speed, 700A-750A of external welding current, 33V-36V of voltage and 25m/H-32m/H of welding speed are selected as external welding current.
8) Turning over and rounding: because the cylinder section is laid for a long time and slightly deforms to cause out-of-tolerance in roundness, the cylinder section of the conical tower is turned over to offset the micro deformation, corresponding reversible deformation is generated after the turning over to offset the deformation, and the roundness at the measuring position is kept within five thousandths of the diameter of the cylinder section to be qualified; the plate is rounded through three steps of loading, rounding and unloading, so that the plate is rounded for 1 to 2 circles in the correction curvature of a roller of a plate bending machine to reach the position of the specified curvature radius, and the steps are as follows: and (3) lowering a carrier roller on one side of the plate rolling machine, hoisting the shell ring needing to be rounded on the plate rolling machine by using a travelling crane, returning the carrier roller to an initial position, rotating a lower roller of the plate rolling machine to drive the shell ring to rotate in the opposite direction, simultaneously lowering an upper roller to press the shell ring to rotate, detecting the curvature radius by using a rounding sample plate during the rotation, lowering the carrier roller on one side of the plate rolling machine, hoisting the shell ring out of the plate rolling machine by using the travelling crane, and finishing the unloading.
9) Longitudinal seam nondestructive testing: and performing UT ultrasonic nondestructive testing on the welding seam, and repairing the welding seam with welding defects according to the process until the welding seam is qualified.
10) Assembling circular seams: assembling the circular seams of the shell ring and the shell ring in place, and connecting the grooves of the shell ring and the shell ring; before formal welding, adopting carbon dioxide gas shielded welding to perform assembly positioning at a butt joint groove between the shell ring and the shell ring by using carbon dioxide gas shielded welding, firstly, transversely assembling and positioning the shell ring into a tower section, then, vertically rotating the shell ring every 300mm from bottom to top to perform spot welding positioning, and adopting a solid gas shielded welding wire E501T-1, a current of 200A-260A, a voltage of 28V-33V and a welding speed of 240mm/min-260 mm/min.
11) Girth welding: firstly, carrying out submerged-arc welding in the cylinder, welding to the cover surface, then finishing the welding on the inner side, then carrying out back gouging on the outer side of the cylinder section by adopting a carbon arc gouging machine, polishing a carburized layer and slag on the surface of the tower frame after back gouging by using a polishing machine until the surface of a welding seam is exposed with metal luster, then carrying out submerged-arc welding on the cover surface, and finishing the welding after the cover surface is welded; specific welding parameters are as follows: welding wire H10Mn2, flux SJ101, current 650A-750A, voltage 29V-33V and welding speed 25m/H-32m/H are adopted inside, and welding wire H10Mn2, flux SJ101, current 700A-750A, voltage 33V-36V and welding speed 25m/H-32m/H are adopted outside;
12) and (5) performing nondestructive detection on the circular seam.
The welding grades of the circular seam and the longitudinal seam are qualified according to the grade I of the No. NB/T47013.3 of pressure-bearing equipment in the current national standard.
Claims (4)
1. A novel large-taper thick plate rolling and assembling process is characterized by comprising the following steps:
s1, blanking and beveling: rolling the sector steel plate of each section of conical cylinder section according to the size requirement, forming a butt joint groove of a longitudinal seam and a circular seam of the plate, and removing impurities near the groove;
s2, rolling: a friction speed reducer is added at the feeding position of the small opening end of the plate, so that the resistance borne by the plate is increased while the small opening end of the plate is feeding, and an upper roller of a plate rolling machine is basically overlapped with a plain line of the plate in the rolling process of the plate;
s3, longitudinal seam positioning and welding: spot welding positioning is carried out before formal welding of longitudinal joints; in the longitudinal seam welding step, firstly, carrying out submerged arc welding inside a tower shell ring, after welding to a cover surface, carrying out back gouging outside the shell ring by adopting a carbon arc gouging machine, polishing a carburized layer and slag after back gouging by using a polishing machine, then carrying out cover surface welding, monitoring UT to be qualified, and welding parameters: h10Mn2 is selected as a welding wire, SJ101 is selected as a welding flux, the internal welding current is 650A-740A, the voltage is 29V-33V, the welding speed is 25m/H-32m/H, the external welding current is 700A-750A, the voltage is 33V-36V, and the welding speed is 25m/H-32 m/H;
s4, turning over and rounding: turning over the conical tower cylinder section to offset micro deformation, and returning to the circle through three steps of loading, rounding and unloading to enable the corrected curvature of the plate to be rolled back to the circle by 1-2 circles in the roller of the plate rolling machine so as to achieve the position of the specified curvature radius;
s5, carrying out longitudinal seam nondestructive testing;
s6, assembling and welding circular seams: assembling the circular seams of the shell ring and the shell ring in place, and connecting the grooves of the shell ring and the shell ring; carrying out submerged-arc welding on the circumferential weld in the cylinder, welding to the cover surface, completing the welding on the inner side, then carrying out back gouging on the outer side of the cylinder section by adopting a carbon arc gouging machine, polishing a carburized layer and slag on the surface of the tower frame after back gouging by using a polishing machine until the surface of a weld joint is exposed with metal luster, then carrying out submerged-arc welding on the cover surface, and finishing the welding after the cover surface is welded; specific welding parameters are as follows: welding wire H10Mn2, flux SJ101, current 650A-750A, voltage 29V-33V and welding speed 25m/H-32m/H are adopted inside, and welding wire H10Mn2, flux SJ101, current 700A-750A, voltage 33V-36V and welding speed 25m/H-32m/H are adopted outside;
and S7, performing nondestructive testing on the circular seam.
2. The new large-taper thick plate rolling and assembling process as claimed in claim 1, wherein in step S2, before the rolling process, the two ends of the plate are pre-bent to a predetermined radius of curvature, a pre-designed bending model is fed between the upper and lower rollers of a four-roller plate rolling machine, the bending model is fixed above the two side rollers by using supports, one end of the plate to be pre-bent is fed onto the bending model of the plate rolling machine, the upper roller is pressed downwards to generate plastic deformation, the other end of the plate is pre-bent, and after pre-bending, the longitudinal center line of the plate is marked by a stone pen to ensure that the generatrix of the plate is strictly parallel to the axial center line of the roller and the parallelism is within 1 mm.
3. The new rolling and assembling process for thick plate with large taper as claimed in claim 1, wherein the parameters of spot welding positioning for longitudinal seam in step S3 and spot welding positioning for circular seam in step S6 are as follows: the welding method is characterized in that the interval is 300mm, the welding length is more than or equal to 50mm, the welding height is 3mm, carbon dioxide gas shielded welding is adopted, the welding wire adopts E501T-1, the welding current is 200A-260A, the voltage is 28V-33V, and the welding speed is 250mm/min-260 mm/min.
4. The new process for rolling and assembling the large-taper thick plate according to claim 1, wherein step S2 is to clean the surface of the plate before the rolling process to remove the oxidized scale on the surface of the plate; when the rolling process is carried out, the air gun is continuously used for blowing the oxide to ensure that the groove and the two sides of the groove are free of impurities within 30 mm.
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN113083958A (en) * | 2021-03-15 | 2021-07-09 | 宁波骋拓金属制造有限公司 | Edge rolling production method |
| CN113560813A (en) * | 2020-11-10 | 2021-10-29 | 江苏海力海上风电装备制造有限公司 | Novel thick plate rolling process |
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| CN113560813A (en) * | 2020-11-10 | 2021-10-29 | 江苏海力海上风电装备制造有限公司 | Novel thick plate rolling process |
| CN113083958A (en) * | 2021-03-15 | 2021-07-09 | 宁波骋拓金属制造有限公司 | Edge rolling production method |
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Application publication date: 20200114 |