CN103212952B - Super large caliber large wall thickness straight-line joint submerged arc welding tube manufacture method - Google Patents
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Abstract
The invention discloses a kind of super large caliber large wall thickness straight-line joint submerged arc welding tube manufacture method, it adopts chemical composition percentage to meet American Petroleum Institute API 5L-2007 (44 editions) standard, microscopic structure is the X80 hot-rolled state steel plate manufacture of AF+B tissue, its manufacturing process comprises the steps: steel plate automatic flaw detection, retaining wall on slope, pre-bending, shaping, prewelding, interior outside weld, first time ultrasonic wave automatic inspection, X-ray examination for the first time, machinery expanding, tube end maching, the water pressure test, retaining wall on slope, second time ultrasonic examination, second time X-ray examination, the manual examination (check) of second time pipe end ultrasonic, appearance and dimension check, post weld heat treatment, outward appearance is through looking into and corrosion-inhibiting coating.Beneficial effect of the present invention is as follows: by the technical controlling that each operation is strict, and solve the every technical barrier producing super large caliber large wall thickness straight-line joint submerged arc welding tube, the properties making final production go out steel pipe meets the requirement of national standard completely.
Description
Technical field
The present invention relates to straight-line joint submerged arc welding tube manufacturing technology field.
Background technology
Petroleum gas is as important energy source, and ratio shared in China's energy resource structure constantly increases, and demand is day by day vigorous.Utilize long distance line petroleum gas to be transported to customer objective ground from grown place, be a kind of safe, efficient and economic means of transportation, this has become the major way of Land petroleum conveying at present.
The grade of steel of China's natural gas main pipeline brings up to X80 by X52, the wall thickness of one-level area caliber φ 1219mm gas trunklines pipeline reaches 22mm, year displacement is 300 billion cubic meters, to year displacement is brought up to more than 450 billion cubic meters, main technological route has two: (1) adopts the technology path improving discharge pressure, requires to bring up to more than 17MPa from existing 12MPa discharge pressure.(2) adopt the technology path increasing conveyance conduit bore, require to bring up to 1422 from existing 1219.
The current world has several at the pipeline of the 45000000000 m3/a displacements built and plan to build, as Muscovite Ba Funiankewo-Wuqia natural gas line, adopt the K65 grade of steel being similar to X80, caliber φ 1420mm, discharge pressure 11.8MPa, mono-tube design displacement about 50,000,000,000 m3/a.In addition, North America is also at the pipeline establishing similar displacement, visible, and the Enlargement Tendency of welded tube bore is obvious.
The direct impact that the increase of caliber and pressure brings is the increase of thickness of steel pipe.The increase of thickness of steel pipe brings difficulty by giving shaping, the welding of the rolling of steel plate and steel pipe.Therefore, make super large caliber large wall thickness straight-line joint submerged arc welding tube and also there is certain defect technically.
Summary of the invention
The technical problem to be solved in the present invention is to provide the super large caliber large wall thickness straight-line joint submerged arc welding tube manufacture method that a kind of properties meets standard-required completely.
For solving the problems of the technologies described above, the technical solution used in the present invention is:
A kind of super large caliber large wall thickness straight-line joint submerged arc welding tube manufacture method, it adopts chemical composition percentage to meet American Petroleum Institute API 5L-2007 (44 editions) standard, microscopic structure is the X80 hot-rolled state steel plate manufacture of AF+B tissue, its manufacturing process comprises the steps: steel plate automatic flaw detection, retaining wall on slope, pre-bending, shaping, prewelding, interior outside weld, first time ultrasonic wave automatic inspection, X-ray examination for the first time, machinery expanding, tube end maching, the water pressure test, retaining wall on slope, second time ultrasonic examination, second time X-ray examination, the manual examination (check) of second time pipe end ultrasonic, appearance and dimension check, post weld heat treatment, visual examination and corrosion-inhibiting coating,
In described retaining wall on slope operation, the angle of the upper and lower groove of steel plate is 34.75 ° ~ 35 °, and upper groove depth is 10.75 ~ 11.25mm; The width of root face is 9.075mm ~ 9.125mm, and angle is 4 °;
Described inside and outside welder's sequence all adopts four Lincoln welds to weld steel pipe inner side and outer side bevel for welding, and gage of wire is 3.9 ~ 4.1mm, and speed of welding is 1.3 ~ 1.35m/min; Weld heat input is 55 ~ 56KJ/cm.
Described molding procedure adopts JCO shaping, first utilize JCO forming machine that the half of the steel plate after pre-flanging is carried out Multi-step forming, be pressed into " J " shape, then second half of steel plate is carried out same Multi-step forming, be pressed into " C " shape, finally make it form " O " shape of opening at the middle pressing one-time of whole steel plate; In above-mentioned Sheet Metal Forming Technology, adopt the compacting number of times of 25 ~ 29 steps, single drafts 180 ~ 190mm.
Described inside and outside welder's sequence all adopts four Lincoln welds to weld steel pipe inner side and outer side bevel for welding; First is DC reverse connection, electric current 1050 ~ 1150A, voltage 30 ~ 34V; Second is interchange, electric current 850 ~ 950A, voltage 32 ~ 36V; 3rd is interchange, electric current 650 ~ 750A, voltage 38 ~ 42V; 4th is interchange, electric current 550 ~ 650A, voltage 38 ~ 42V.
In described machinery expanding operation, steel pipe total length is carried out 0.5% ~ 1.2% expanding.
Beneficial effect of the present invention is as follows:
(1) by the composition to X80 steel plate, tissue and heat treated control, steel plate is made to have high tenacity and good welding performance.
(2) by JCO moulding process, according to steel plate width, thickness, intensity and die size, Accurate Analysis determines rational punching press number of times and single drafts, solve the super large caliber large wall thickness straight-line joint submerged arc welding tube JCO forming process light plate resilience that X80 steel-grade diameter is φ 1422mm, wall thickness is 30.8mm little, the tubular difficult problem being not easy to control, according to analysis result and field trial, analyze steel plate forming process spring-go amount, rationally determine draught per pass, after making steel pipe forming, there is good circularity and body is directly spent.
(3), in welding procedure, first by selecting special welding material, guarantee that weld seam has the intensity of a little higher than mother metal and good toughness.When determining welding parameter; take into full account the effect of each silk in three wire bonds; by each silk electric current of reasonable set, voltage, angle, distance between weldingwires and speed of welding, make weld seam obtain suitable depth of penetration and good pattern, be conducive to gas and covering slag in welding process simultaneously and float.On this basis, in order to reduce the impact of sweating heat on heat affected area toughness, each silk Current Voltage being optimized further, taking lower welding wire energy, ensure the performance of welding heat affected zone.Weld seam finally obtain based on acicular ferrite and ferrite bainite, the tissue with excellent toughness, welding heat affected zone obtains the tissue of tiny granular bainite and ferrite bainite simultaneously, solves the tough sex chromosome mosaicism of Steel Welded Joint.
(4) in expanding technology, according to the apparent size situation after steel pipe forming, the enlarging rate obtaining optimum efficiency is determined by numerical analysis, verify again by field trial with to the result of correlated performance data analysis, determine best expanding technology, after guaranteeing pipe expanding, apparent size and physicochemical property meet standard-required, solve steel pipe when machinery expanding because work hardening causes the problem that intensity increases, toughness and uniform elongation reduce, also improve pipe end circularity and body simultaneously and the important appearance index such as directly to spend.
Detailed description of the invention
Embodiment
Adopt the X80 hot-rolled state steel plate that chemical composition percentage meets American Petroleum Institute API 5L-2007 (44 editions) standard, microscopic structure is AF+B tissue, carry out the manufacture that caliber is 1422mm, wall thickness is the straight-line joint submerged arc welding tube of 30.8mm, concrete technology step is as follows:
(1) ultrasonic wave steel plate automatic flaw detection: utilize full-automatic steel plate ultrasonic test equipment, checks within the scope of the edges of boards 50mm of steel plate both sides and middle part.
(2) milling limit, retaining wall on slope: the bevel angle up and down of steel plate is 35 °, the width of root face is 9.1mm.The object of finished edge ensures that welding process can complete penetration, forms suitable seam center, avoid occurring the defects such as lack of penetration in high-speed welding process, guarantee the quality of welding point, realize good quality and high output.Steel plate is chosen according to Steel Pipe Design diameter and thickness, and at steel plate both sides milling bevel for welding corresponding to weld seam.
(3) pre-bending: require and caliber size requirement according to steel pipe curvature, adopts pre-flanging machine that edges of boards are bent to satisfactory curvature.
(4) JCO is shaping: employing caliber is φ 1422mm, wall thickness is the steel pipe of 30.8mm, first utilize JCO forming machine that the half of the steel plate after pre-flanging is carried out Multi-step forming, be pressed into " J " shape, same Multi-step forming is carried out again by its second half, be pressed into " C " shape, finally make it form " O " shape of opening at the middle pressing one-time of whole steel plate; In above-mentioned Sheet Metal Forming Technology, adopt the compacting number of times of 27 steps, single drafts 185mm.
(5) prewelding: by the position of adjustment joint close Prewelding machine pressure roller; make coupling that the bevel for welding of shaping rear steel pipe is good together; guarantee misalignment, gap size meet the requirements; adopt gas shielded welding mode to weld simultaneously; form continuous, specification, stay-in-grade pre-welding line, time astute and able inside and outside guaranteeing, steel-pipe welding operating mode is stable.
(6) interior outside weld: adopt four Lincoln welds to weld at steel pipe inner side and outer side bevel for welding; First is DC reverse connection, electric current 1100A, voltage 32V; Second is interchange, electric current 900A, voltage 34V; 3rd is interchange, electric current 700A, voltage 40V; 4th is interchange, electric current 600A, voltage 40V; Gage of wire is 4.0mm; Speed of welding is 1.3 ~ 1.35m/min; Weld heat input is 55 ~ 56KJ/cm.
(7) first time pipe end ultrasonic manual examination (check): manual ultrasonic examination is carried out to the weld seam within the scope of pipe end 300mm and weld seam two side areas;
(8) first time ultrasonic wave automatic inspection: ultrasonic examination is carried out to the steel pipe inner and outer welding after welding and heat affected area, weld seam both sides part;
(9) first time X-ray examination: adopt image processing system to welding after steel pipe inner and outer welding carry out 100% industrial television inspection, ensure flaw detection sensitivity.
(10) machinery expanding: steel pipe total length is carried out 0.5% ~ 1.2% expanding with the apparent size precision improving steel pipe, as ovality, linearity, and improve the internal stress distribution of steel pipe.
(11) tube end maching: process Steel pipe end surface, ensures smooth.For the good seal of next step water pressure test is ready.
(12) water pressure test: steel pipe is carried out to the hydrostatic test of 100%, test pressure is 90% ~ 100% of regulation SMYS, checks the strength level of steel pipe and whether there is leakage point.
(13) retaining wall on slope: the above-mentioned steel pipe be up to the standards is carried out tube end maching, reaches the pipe end slope-mouth dimensional requirement of customer requirement.
(14) second time ultrasonic examination: the steel pipe inner and outer welding after expanding, hydraulic pressure and heat affected area, weld seam both sides part are carried out to the inspection of 100%, to get rid of expanding, the issuable defect of hydraulic pressure.
(15) second time X-ray examination: to the steel pipe inner and outer welding after expanding, hydraulic pressure carry out 100% industrial television inspection and pipe end film making check, to get rid of expanding, the issuable defect of hydraulic pressure.
(16) second time pipe end ultrasonic manual examination (check): the body within the scope of pipe end 300mm, weld seam and heat affected area, weld seam both sides part, groove face are checked.
(17) appearance and dimension check: shaping steel tube apparent size is measured according to designing requirement.
(18) post weld heat treatment: heat-treat according to the heat treatment parameter butt welded seam designed and heat affected area, weld seam both sides part, release welding interior stress.
(19) outward appearance is through looking into and corrosion-inhibiting coating: the steel pipe complete to heat treatment carries out pipe end ovality and body directly spends inspection, and qualified steel pipe carries out coating and preservative treatment according to designing requirement to steel pipe inner wall or outer wall.
In sum, by the technical controlling that each operation is strict, the properties of final steel pipe is made to meet the requirements of " natural-gas transfer pipeline OD1422mm X80 straight-line joint submerged arc welding tube technical conditions exposure draft " completely.
Claims (3)
1. a super large caliber large wall thickness straight-line joint submerged arc welding tube manufacture method, it is characterized in that, it adopts chemical composition percentage to meet American Petroleum Institute API 5L-2007 (44 editions) standard, microscopic structure is the X80 hot-rolled state steel plate manufacture of AF+B tissue, its manufacturing process comprises the steps: steel plate automatic flaw detection, retaining wall on slope, pre-bending, shaping, prewelding, interior outside weld, first time ultrasonic wave automatic inspection, X-ray examination for the first time, machinery expanding, tube end maching, the water pressure test, retaining wall on slope, second time ultrasonic examination, second time X-ray examination, the manual examination (check) of second time pipe end ultrasonic, appearance and dimension check, post weld heat treatment, visual examination and corrosion-inhibiting coating,
In described retaining wall on slope operation, the angle of the upper and lower groove of steel plate is 34.75 ° ~ 35 °, and upper groove depth is 10.75 ~ 11.25mm; The width of root face is 9.075mm ~ 9.125mm, and angle is 4 °;
Described inside and outside welder's sequence all adopts four Lincoln welds to weld steel pipe inner side and outer side bevel for welding, and gage of wire is 3.9 ~ 4.1mm, and speed of welding is 1.3 ~ 1.35m/min; Weld heat input is 55 ~ 56KJ/cm;
In described machinery expanding operation, steel pipe total length is carried out 0.5% ~ 1.2% expanding.
2. super large caliber according to claim 1 large wall thickness straight-line joint submerged arc welding tube manufacture method, it is characterized in that, described molding procedure adopts JCO shaping, first utilize JCO forming machine that the half of the steel plate after pre-flanging is carried out Multi-step forming, be pressed into " J " shape, then second half of steel plate is carried out same Multi-step forming, be pressed into " C " shape, finally make it form " O " shape of opening at the middle pressing one-time of whole steel plate; In above-mentioned Sheet Metal Forming Technology, adopt the compacting number of times of 25 ~ 29 steps, single drafts 180 ~ 190mm.
3. super large caliber according to claim 1 large wall thickness straight-line joint submerged arc welding tube manufacture method, is characterized in that, described inside and outside welder's sequence all adopts four Lincoln welds to weld steel pipe inner side and outer side bevel for welding; First is DC reverse connection, electric current 1050 ~ 1150A, voltage 30 ~ 34V; Second is interchange, electric current 850 ~ 950A, voltage 32 ~ 36V; 3rd is interchange, electric current 650 ~ 750A, voltage 38 ~ 42V; 4th is interchange, electric current 550 ~ 650A, voltage 38 ~ 42V.
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| CN103521549B (en) * | 2013-10-07 | 2015-09-16 | 宝鸡石油钢管有限责任公司 | A kind of manufacture method of X100 Hi-grade steel heavy caliber thick wall straight-line joint submerged arc welding tube |
| CN106694609A (en) * | 2015-11-16 | 2017-05-24 | 宝鸡石油钢管有限责任公司 | Method for manufacturing X80-stage phi1422 mm longitudinal submerged arc welding pipe |
| CN105834697B (en) * | 2016-05-20 | 2017-09-05 | 中国石油大学(华东) | The manufacture method of X80 pipe line steel ERWs |
| CN106694610A (en) * | 2017-03-29 | 2017-05-24 | 无锡市蓝博金属制品有限公司 | Preparation process of oil filler pipe |
| CN108581375A (en) * | 2018-04-08 | 2018-09-28 | 太原科技大学 | A kind of preparation method having the stainless steel and carbon steel composite tube that cover side |
| CN109530855B (en) * | 2018-12-24 | 2021-09-10 | 合肥紫金钢管股份有限公司 | Welding method of large-opening longitudinal submerged arc welded steel pipe for offshore wind power |
| CN111719085A (en) * | 2020-06-30 | 2020-09-29 | 中国石油集团渤海石油装备制造有限公司 | Marine vessel and method of making same |
| CN111872645A (en) * | 2020-08-06 | 2020-11-03 | 中国石油天然气集团有限公司 | Manufacturing method of X80 steel grade OD1422mm large-wall-thickness straight welded pipe |
| CN114535939B (en) * | 2022-03-22 | 2023-02-28 | 湖南胜利湘钢钢管有限公司 | Method for manufacturing longitudinal submerged arc welded pipe |
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Effective date of registration: 20200921 Address after: 100007 Beijing, Dongzhimen, North Street, No. 9, No. Patentee after: CHINA NATIONAL PETROLEUM Corp. Patentee after: CNPC Bohai Petroleum Equipment Manufacturing Co.,Ltd. Patentee after: NANJING JULONG STEEL PIPE Co.,Ltd. Patentee after: JULONG STEEL PIPE Co.,Ltd. Address before: 300457, No. 3, Tianjin TEDA service outsourcing industry park, No. 19 West Ring Road, Tianjin, Tanggu Patentee before: CNPC Bohai Petroleum Equipment Manufacturing Co.,Ltd. Patentee before: NANJING JULONG STEEL PIPE Co.,Ltd. Patentee before: JULONG STEEL PIPE Co.,Ltd. Patentee before: HEBEI HUAYOU STEEL PIPE DESIGN RESEARCH INSTITUTE Co.,Ltd. |