CN103331527A - Erecting welding method of major-diameter finished flange - Google Patents

Erecting welding method of major-diameter finished flange Download PDF

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Publication number
CN103331527A
CN103331527A CN2012105507051A CN201210550705A CN103331527A CN 103331527 A CN103331527 A CN 103331527A CN 2012105507051 A CN2012105507051 A CN 2012105507051A CN 201210550705 A CN201210550705 A CN 201210550705A CN 103331527 A CN103331527 A CN 103331527A
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flange
welding
cylindrical shell
finished product
welding method
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CN2012105507051A
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CN103331527B (en
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魏炳宁
林海桥
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Nantong Zhenhua Heavy Equipment Manufacturing Co Ltd
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Nantong Zhenhua Heavy Equipment Manufacturing Co Ltd
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Abstract

The invention relates to an erecting welding method of a major-diameter finished flange, which comprises the following steps that technology supports and turnover lifting lugs are arranged in a barrel; the barrel is turned over; the flange is hoisted onto a flange mold; the barrel is hoisted onto the flange; positioned welding is performed; the barrel is assembled; a conical barrel assembly is hoisted onto a roller carrier and assembled with a barrel assembly; and circular seams of the barrel are welded. The method has the advantages that the flange with the diameter of 4-7m is machined in place when being supplied, no machining allowance exists, and the tumble-home degree of the flange is controlled within a tolerance range by adjusting a welding sequence, so that a machining technology is simplified, the production cost is lowered, the production efficiency is improved, and the manufacturing period is shortened.

Description

The erection welding method of big footpath finished product flange
Technical field
The present invention relates to the welding of a kind of wind-powered electricity generation pile tube cylindrical shell and flange, and guarantee the flatness of flange face and the technical method of end face of flange and tubular axis perpendicularity, be used for assembling between wind-powered electricity generation conic tube assembly, isometrical cylinder assembly and the flange, welding.
Background technology
The cleaning sustainable energy is the future source of energy developing direction, and wind-power electricity generation is first-selected clean energy resource, and Oversea wind power generation is main body especially, and offshore wind farm generating set main body structure is made up of foundation pile, blower fan tower barrel and generating set etc.Between blower fan tower barrel and the foundation pile, all be connected by flange between generating set and the tower tube, flange diameter generally between 4m ~ 7m, thickness is generally between 80mm ~ 20mm, flange has become to bear the critical piece of tower tube and generating set, and most of flange is forge piece.The main holding capacity of flange has: wind-force acts on thrust, moment of torsion moment of flexure, the vibrations of generating set and the swing of stressed variation on the impeller.
Intact in order to guarantee so large-sized two flanges contact, after foundation pile or tower tube complete, flange face requires " introversion is flat " outward, and the corresponding pretightning force of the high-strength bolt that can give to connect during installation is not so allow to occur the turning inside-out phenomenon in the manufacturing process.End face of flange integral smoothness≤2mm, end face and tubular axis perpendicularity deviation≤2mm, end face introversion amount is between 0~1.5mm.
The wind-powered electricity generation project was put allowance in advance by flange in the past, and after flange and cylindrical shell welding were finished, plane on the whole processing flange guaranteed the flange face flatness, and flange face and tubular axis perpendicularity.Its shortcoming is: the processing technology complexity, increased production cost, and reduced production efficiency, prolonged the making duration, and equipment has been had relatively high expectations.
Summary of the invention
The object of the invention provides a kind of erection welding method of wind-powered electricity generation finished product flange, with the processing technology complexity that the solution prior art exists, and the production cost height, production efficiency is low, makes problem long in time limit.
Technical scheme of the present invention is: comprise following content:
(1) group is to the assurance of cylinder roundness: use specific equipment to guarantee to be about to group to the port circularity at cylindrical shell two ends;
(2) assurance of planeness of flange: the welding ends of flange is placed on the dedicated platform up, and the uneven place of flange guarantees the Flange Plane flatness by increasing pad, after flatness is adjusted to the right place, fixes with bolt and flange mold;
(3) assurance of tubular axis and Flange Plane perpendicularity: be grouping with flange under the tubular axis plumbness, adjust gap and the wrong variable of barrel port and flange craft port, thereby guarantee tubular axis and Flange Plane perpendicularity;
(4) location welding after cylindrical shell and the flange adjustment requires: welding 100mm, 200mm at interval; In the carbon dioxide gas arc welding bottoming welding of the weld seam outside;
(5) the cylindrical shell group is right: after the cylinder assembly that backing welding is connected cylindrical shell 2 and flange 8 stands up, be placed on the turning rolls 4;
(6) 1 lifting of conic tube assembly is assembled with described cylinder assembly to turning rolls 4;
(7) cylindrical shell girth welding: with the girth welding between cylindrical shell 2 two ends and conic tube assembly 1 and the flange 8.
Advantage of the present invention is: processed during the flange supplied materials and put in place, do not had allowance, adjusted welding sequence but utilize, with the negative camber control of flange in the margin of tolerance.Simplify processing technology, reduced production cost, improved production efficiency, shortened the making duration.
Description of drawings
Fig. 1 is that the conic tube assembly that the present invention welds is equipped with the axial cutaway view of technology support.
Fig. 2 is that the cylindrical shell that the present invention welds is equipped with the axial cutaway view of technology support.
Fig. 3 is that described conic tube assembly or cylindrical shell are arranged on the end face structure schematic diagram on the turning rolls.
Fig. 4 is the axial cutaway view of flange mold of the present invention.
Fig. 5 is the vertical view of Fig. 8.
Fig. 6 is the schematic diagram of lifting flange.
Fig. 7 is the vertical view of Figure 10 turned flange.
The structural representation of the bait that Fig. 8 adopts when being the lifting flange.
Fig. 9 lifts process schematic diagram on the flange with cylindrical shell.
Figure 10 is that cylindrical shell lifts the schematic diagram after finishing on the flange.
Figure 11 is the enlarged drawing (sectional view behind butt joint groove and the backing welding) at P place among Figure 14.
Figure 12 is the enlarged drawing (cross-sectional view of flange) at M place among Figure 14.
Figure 13 is positioned over schematic diagram on the turning rolls with cylindrical shell.
Figure 14 be the conic tube assembly is lifted on the turning rolls and with the cylindrical shell group to after schematic diagram.
Figure 15 is cylindrical shell girth welding schematic diagram.
The specific embodiment
Referring to Fig. 1~Figure 15, the welding method of wind-powered electricity generation foundation pile finished product flange of the present invention, in order to satisfy tolerance, avoid occurring the turning inside-out phenomenon, made flange and assembled special-purpose mold, and formulated effective flange erection welding process program, the end face negative camber of flange 2 has been controlled at 0.3~0.5mm, last integral plane flatness≤1.5mm, pile body axis and end face of flange perpendicularity deviation are no more than 2mm.
When flange 2 is grouping with cylindrical shell 1, must carry out platform plane degree≤0.5mm to platform a bigger group of rigidity.Flange 2 is machined piece, cylindrical shell 1 two ends of docking with flange 2 adopt machined to finish equally, during adjustment flange 2 and the gap between the cylindrical shell 1 are adjusted to consistently, guarantee the welding contracted quantity unanimity, behind the some points of flange 2 circumference five equilibriums, record the Flange Plane degrees of data of each point.
In welding process, can adjust welding road number with reference to the data of monitoring point, guaranteed the flatness of flange postwelding.In the weld seam welding process between flange 2 and the cylindrical shell 1, by monitoring flange Internal and external cycle flatness data, adjust the weld seam welding sequence, the negative camber of flange 2 is controlled in the margin of tolerance.
Concrete technological process is as follows:
1, cylindrical shell increases the technology support:
1.1 support 11 and 21 according to illustrated in figures 1 and 2 at conic tube assembly 1 and (isometrical) cylinder 2 two ends difference mounting process.The support of described technology is by central plate 211, locating piece 212 and strut 213, and central plate 211 is located at the center of cylindrical shell, and 6 locating pieces 212 are uniformly distributed along the circumference at the inner peripheral surface of cylindrical shell, is connected a strut 213 between each locating piece 212 and central plate 211.
Require: before the technology support is installed and after installing, need to check the circularity of cylindrical shell, requirement≤3mm.
2, flange 8 dimensional measurements: flange 8 is placed on the horizontal moulding bed, measure its circularity, end face negative camber, end face flatness.
3, the adjustment of flange mold 6 (referring to Fig. 4-Figure 12):
3.1 adjust the integral smoothness of flange mold 6 and flange fitting surface, require flatness≤1.5mm.
3.2 will pad between flange mold 6 and the ground.
As Fig. 4-shown in Figure 5, described flange mold 6 comprises ring dish 61, cylinder 62, riser 63, four-bladed vane 64, is connected with a plurality of risers radially with cylinder between two ring dishes of upper and lower settings, and riser is uniform along cylinder; In the ring dish, connect four-bladed vane; The neighboring of superincumbent ring dish is a plurality of guide plates 7 of welding evenly.
4, lifting flange 8:
4.1 according to Fig. 6-shown in Figure 7, is connected 4 hangers 9 with suspension hook 5 with shackle 52 by steel wire rope, flange 8 is lifted to flange mold 6, and the welding ends 81 that makes flange 8 up.On four suspension centres and the flange mold four than the macropore contraposition.
Described hanger 9 is made up of shackle plate 91 and bolt 92, is provided with lifting hole(eyelet) 912 on the top of shackle plate 91 and is used for being connected with shackle 52; Be provided with groove 911 is used for the nut of stud bolt 92 and is welded to each other in the bottom of shackle plate 91.During lifting bolt 92 is inserted in the through hole 83 of flange 8, fastening with nut.
5, flange adjustment: after flange 8 lifts on the flange mold 6, adjust overall leveling and the circularity of flange 8, and measurement data, qualified back is tightened flange and flange mold fixing with bolt.
6, cylindrical shell lifting:
6.1 according to being equipped with four steel wire ropes as shown in Figure 9, connect 4 points that 4 10t steel plate pincers 52 are clamped cylindrical shell 2 upper ends, cylindrical shell 2 lifted to flange 8.
6.2 adjust unfitness of butt joint, the axis of cylindrical shell 2 and the plane verticality of flange 8 of cylindrical shell 2 and flange 8.Require: unfitness of butt joint≤2mm, misalignment of axe≤3mm.
6.3 according to the welding procedure specification (WPS) location welded flange 811 of approval and the weld seam between the cylindrical shell 2, require: welding 100mm, 200mm at interval.
6.4 bottoming welding between cylindrical shell 2 and flange 811 as shown in figure 11.
6.5 before the weldering, welding process and postwelding all need the pile body linearity is detected.
7, the cylindrical shell group is right:
7.1 cylindrical shell 2 is stood up back (axially transferring level to), be placed on the turning rolls 4, by adjusting weld gap and the wrong variable between conic tube assembly 1 and the cylindrical shell 2, guarantee Flange Plane and cylindrical shell 1 assembly axis verticality≤1.5mm.
7.2 with conic tube assembly 1 lifting to the conic tube turning rolls with part 1 component assembling (Figure 17-Figure 15).Described turning rolls 4 is fixed on the built-in fitting of ground; This turning rolls 4 comprises at least two pairs of cylindrical shell rollers 41 for support cylindrical shell 2, is used at least two pairs of conic tube rollers 42 of cone of support cylinder assembly 1, and the gear wheel 43 that is used for propping up conic tube assembly 1 bigger diameter end.
8, cylindrical shell girth welding: with girth welding equipment 19 with the circumferential weld 18(between cylindrical shell 2 two ends and conic tube assembly 1 and the flange 8 referring to Figure 15) weld (interior external welding belongs to routine techniques).

Claims (7)

1. the erection welding method of one kind big footpath finished product flange is characterized in that, comprises following content:
(1) group is to the assurance of cylinder roundness: use specific equipment to guarantee to be about to group to the port circularity at cylindrical shell two ends;
(2) assurance of planeness of flange: the welding ends of flange is placed on the dedicated platform up, and the uneven place of flange guarantees the Flange Plane flatness by increasing pad, after flatness is adjusted to the right place, fixes with bolt and flange mold;
(3) assurance of tubular axis and Flange Plane perpendicularity: be grouping with flange under the tubular axis plumbness, adjust gap and the wrong variable of barrel port and flange craft port, thereby guarantee tubular axis and Flange Plane perpendicularity;
(4) location welding after cylindrical shell and the flange adjustment requires: welding 100mm, 200mm at interval; In the carbon dioxide gas arc welding bottoming welding of the weld seam outside;
(5) the cylindrical shell group is right: after the cylinder assembly that backing welding is connected cylindrical shell 2 and flange 8 stands up, be placed on the turning rolls 4;
(6) 1 lifting of conic tube assembly is assembled with described cylinder assembly to turning rolls 4;
(7) cylindrical shell girth welding: with the girth welding between cylindrical shell 2 two ends and conic tube assembly 1 and the flange 8.
2. the erection welding method of big footpath according to claim 1 finished product flange, it is characterized in that, described equipment is by central plate 211, locating piece 212 and strut 213, central plate 211 is located at the center of cylindrical shell, a plurality of locating pieces 212 are uniformly distributed along the circumference at the inner peripheral surface of cylindrical shell, are connected a strut 213 between each locating piece 212 and central plate 211.
3. the erection welding method of big footpath according to claim 2 finished product flange, it is characterized in that, described flange mold 6 comprises ring dish 61, cylinder 62, riser 63, four-bladed vane 64, is connected with a plurality of risers radially with cylinder between two ring dishes of upper and lower settings, and riser is uniform along cylinder; In the ring dish, connect four-bladed vane; The neighboring of superincumbent ring dish is a plurality of guide plates 7 of welding evenly.
4. the erection welding method of big footpath according to claim 3 finished product flange is characterized in that the outside of described flange 8 one ends is provided with flange 81 as welding ends, is provided with butt joint groove 811 in inboard and the outside on the top of this flange 81; Welding ends at cylindrical shell 2 is provided with the butt joint groove that docks groove 811 same types with this, and slope type becomes certain ratio with steel plate thickness.
5. the erection welding method of big footpath according to claim 4 finished product flange is characterized in that, in the described step (4), adjusts the integral smoothness of flange mold 6 and flange 8 welding ends 81, requires flatness≤1.5mm.
6. the erection welding method of big footpath according to claim 5 finished product flange is characterized in that, in the described step (5), behind the some points of flange 8 circumference five equilibriums, records the data of each some planeness of flange; In welding process, with reference to the data of monitoring point, adjust welding road number, guaranteed the flatness of flange postwelding; In the weld seam welding process between flange 8 and cylindrical shell 2, by monitoring Flange Plane Internal and external cycle flatness data, adjust the weld seam welding sequence, the negative camber of flange 82 postweldings is controlled in the described margin of tolerance.
7. the erection welding method of big footpath according to claim 1 finished product flange is characterized in that, the turning rolls 4 in the described step (7) is fixed turning rolls roller linearity deviation≤1mm with ground; This turning rolls 4 comprises at least two pairs of cylindrical shell rollers 41 for support cylindrical shell 2, is used at least two pairs of conic tube rollers 42 of cone of support cylinder assembly 1, and the gear wheel 43 that is used for propping up conic tube assembly 1 bigger diameter end; Adjust conic tube assembly 1 and cylindrical shell 2 gaps, abutment joint place and wrong variable, guarantee end face of flange and tubular axis perpendicularity≤1.5mm.
CN201210550705.1A 2012-12-18 2012-12-18 The erection welding method of large footpath finished product flange Active CN103331527B (en)

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Cited By (11)

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Publication number Priority date Publication date Assignee Title
CN104084771A (en) * 2014-07-06 2014-10-08 山西汾西重工有限责任公司 Destressing warhead-curve-shaped aluminum alloy thin-walled cylinder and machining process of destressing warhead-curve-shaped aluminum alloy thin-walled cylinder
CN104625446A (en) * 2014-12-15 2015-05-20 湖北三江航天红阳机电有限公司 Rolling cone piece butt joint welding method
CN105290715A (en) * 2014-06-19 2016-02-03 上海振华重工(集团)股份有限公司 Conical cylinder body and straight cylinder body arc flange assembling and machining method
CN105817783A (en) * 2016-05-27 2016-08-03 四川蓝星机械有限公司 Butt-jointing and assembly welding method of cone cylinders
CN107322173A (en) * 2017-08-28 2017-11-07 南通振华重型装备制造有限公司 A kind of high-efficiency welding method of the high-strength steel flanges of S460NL
CN108637594A (en) * 2018-03-30 2018-10-12 南通振华重型装备制造有限公司 A kind of true flange production method of supporting leg
CN108890167A (en) * 2018-09-19 2018-11-27 张化机(苏州)重装有限公司 The manufacture craft of large-scale tower cylinder
CN111468896A (en) * 2020-04-13 2020-07-31 上海妙城智能科技有限公司 Process for replacing flange on wind tower foundation ring
CN112518243A (en) * 2020-11-23 2021-03-19 江苏海力海上风电装备制造有限公司 Novel manufacturing process of long and narrow thick plate transition section of wind power tower
CN113814641A (en) * 2021-11-01 2021-12-21 内蒙古特变电工能源装备有限公司 Special flange and tower section assembling machine for wind power tower cylinder manufacturing and method for applying special flange and tower section assembling machine
CN113998323A (en) * 2021-11-01 2022-02-01 上海锅炉厂有限公司 Outer cylinder structure, inner support mounting device thereof and manufacturing process method

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Cited By (14)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN105290715A (en) * 2014-06-19 2016-02-03 上海振华重工(集团)股份有限公司 Conical cylinder body and straight cylinder body arc flange assembling and machining method
CN105290715B (en) * 2014-06-19 2017-08-25 上海振华重工(集团)股份有限公司 Conic tube and the assembling of straight barrel circular arc flange and machining manufacture
CN104084771A (en) * 2014-07-06 2014-10-08 山西汾西重工有限责任公司 Destressing warhead-curve-shaped aluminum alloy thin-walled cylinder and machining process of destressing warhead-curve-shaped aluminum alloy thin-walled cylinder
CN104084771B (en) * 2014-07-06 2016-04-06 山西汾西重工有限责任公司 The processing technology of the aluminium alloy thin-walled cylinder of destressing bullet curve shape
CN104625446A (en) * 2014-12-15 2015-05-20 湖北三江航天红阳机电有限公司 Rolling cone piece butt joint welding method
CN105817783A (en) * 2016-05-27 2016-08-03 四川蓝星机械有限公司 Butt-jointing and assembly welding method of cone cylinders
CN107322173A (en) * 2017-08-28 2017-11-07 南通振华重型装备制造有限公司 A kind of high-efficiency welding method of the high-strength steel flanges of S460NL
CN108637594A (en) * 2018-03-30 2018-10-12 南通振华重型装备制造有限公司 A kind of true flange production method of supporting leg
CN108890167A (en) * 2018-09-19 2018-11-27 张化机(苏州)重装有限公司 The manufacture craft of large-scale tower cylinder
CN111468896A (en) * 2020-04-13 2020-07-31 上海妙城智能科技有限公司 Process for replacing flange on wind tower foundation ring
CN112518243A (en) * 2020-11-23 2021-03-19 江苏海力海上风电装备制造有限公司 Novel manufacturing process of long and narrow thick plate transition section of wind power tower
CN113814641A (en) * 2021-11-01 2021-12-21 内蒙古特变电工能源装备有限公司 Special flange and tower section assembling machine for wind power tower cylinder manufacturing and method for applying special flange and tower section assembling machine
CN113998323A (en) * 2021-11-01 2022-02-01 上海锅炉厂有限公司 Outer cylinder structure, inner support mounting device thereof and manufacturing process method
CN113998323B (en) * 2021-11-01 2022-11-25 上海锅炉厂有限公司 Outer cylinder structure, inner support mounting device thereof and manufacturing process method

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