CN102409229B - N80Q grade straight seam ERW (Electric Resistance Welding) petroleum casing and manufacturing method thereof - Google Patents

N80Q grade straight seam ERW (Electric Resistance Welding) petroleum casing and manufacturing method thereof Download PDF

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CN102409229B
CN102409229B CN201010291443.2A CN201010291443A CN102409229B CN 102409229 B CN102409229 B CN 102409229B CN 201010291443 A CN201010291443 A CN 201010291443A CN 102409229 B CN102409229 B CN 102409229B
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rolling
tube
electric resistance
resistance welding
petroleum casing
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黄明浩
黄国建
张禄林
张英慧
孔祥磊
徐烽
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Angang Steel Co Ltd
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Abstract

The invention provides an N80Q grade straight seam ERW (Electric Resistance Welding) petroleum casing and a manufacturing method thereof. The N80Q grade straight seam electric resistance welding petroleum casing comprises the following components: 0.15-0.20% of C, 0.15-0.30% of Si, 1.40-1.80% of Mn, less than or equal to 0.020 of P, less than or equal to 0.008% of S, 0.010-0.030 of Ti, 0.02-0.05% of Als, 0.01-0.04% of Nb and the rest Fe. The manufacturing method comprises the following steps of: pretreating molten iron; refining molten steel; refining at the outer part of a furnace; continuous casting for a plate blank; rolling; tube manufacturing through ERW; and whole tube tempering and heat treatment, wherein during the rolling process, the plate blank is heated to 1,200-1,300 DEG C; the hot rolling is controlled through two stages, at the first stage, the initial rolling temperature is 1,180-1,280 DEG C, the final rolling temperature is over 980 DEG C, at the second stage, the initial rolling temperature is below 960 DEG C, and the final rolling temperature is 720-840 DEG C; after rolling, a plate coil is cooled at the speed of 6-19 DEG C/s, and the coiling temperature is 470-600 DEG C; and during the whole tube tempering, the whole tube is heated to 880-950 DEG C, the heat preservation time is over 30min, then water quenching is carried out on the whole tube, the whole tube is heated to 550-600 DEG C, the heat preservation time is over 80min, and final, air cooling and tempering are carried out. According to the invention, the plate coil alloy has low cost, the welding and the impact toughness are good, the tube manufacturing and formation are easy, and the tube body can be ensured to be consistent with the weld seam in property.

Description

N80Q rank straight slit electric resistance welding petroleum casing pipe and manufacture method thereof
Technical field
The invention belongs to metallic substance high-strength low-alloy steel technical field, be specifically related to a kind of high strength petroleum sleeve pipe and manufacture method thereof, particularly a kind of N80Q vertical masonry joint resistance welding (ERW) petroleum casing pipe and manufacture method thereof in API Spec 5CT standard, its As rolled coiled sheet performance is API J55 grade of steel, and the modified rear performance of homogeneous tube is API N80Q grade of steel.
Background technology
Petroleum casing pipe is one of the most frequently used oil country tubular good in oil field, and consumption is large, spends many, is requisite construction material in oil-gas field drill operation, in oil-gas field production development process, has extremely important effect.
The API Spec 5CT of API standard code, petroleum casing pipe can adopt seamless tube and the manufacture of ERW longitudinal resistance welded pipe.ERW petroleum casing pipe, claims again high frequency sews resistance welding sleeve pipe.Compare with seamless tube, have that wall thickness is even, dimensional precision is high, perforation performance is good, the anti-ability of ruining of squeezing is strong, and the low significant advantage that waits of cost, can substitute same grade of steel seamless casing to use in oil field, is subject to managing the favor in factory and oil field.
The traditional processing technology of straight slit electric resistance welding petroleum casing pipe is: first, according to the requirement of petroleum casing pipe performance, design suitable chemical composition, smelt and be rolled into hot-rolled sheet coil; Then, coiled sheet is made to longitudinal welded pipe by ERW mode, and Welded Pipe weld seam or welded tube integral body heat-treats, subsequently pipe end is carried out to suitable screw thread processing, final production goes out qualified petroleum casing pipe.
API Spec 5CT standard code, the yield strength of N80Q steel level oil bushing body is 552~785MPa, tensile strength >=689MPa, horizontal Charpy-V impact power >=20J in the time of 0 ℃.Because this steel-grade bushing intensity is higher, reached the limit of ERW unit tubulation ability, if directly adopt N80 rank hot-rolled sheet coil to carry out tubulation, can bring certain difficulty to moulding.Therefore, can adopt compared with other J55 hot-rolled sheet coil of low intensity level and carry out ERW welding tube-making, then carry out homogeneous tube thermal treatment, make the final performance of steel pipe reach N80Q stratification levels.And weld seam and body carry out identical thermal treatment process, finally organizing of obtaining is identical, effectively alleviates tissue, the performance difference of weld seam and body, eliminates unrelieved stress, improves the quality of steel pipe integral.
Before the present invention, document or the patents of invention of existing a plurality of relevant N80Q grade of steel ERW petroleum casing pipes, but in adopting in carbon the N80Q level ERW petroleum casing pipe of manganese, low-cost design report seldom, below simply introduce document and the patent comparatively approaching with the present invention:
1) Chinese patent CN101376943A, 80ksi grade of steel straight welding oil annular tube steel, sleeve pipe and manufacture method.In composition, containing Mo:0.1-0.5%, after tubulation, carry out the modified thermal treatment of homogeneous tube.
2) Chinese patent CN101643883A, N80, P110, L80 grade of steel straight welding oil annular tube steel and cover pipe manufacturer.C:0.10-0.24% in this patent, lower limit, in peritectoid district, is not suitable for continuous casting and produces; Add alloy Cr:0.3-0.6%, Nb:0.12-0.14, V:0.08-0.12, cost is higher; After tubulation, carry out the modified thermal treatment of homogeneous tube.
3) Japanese Patent JP58093821A, the manufacture method of electricresistance welded steel pipe for oil well.C:0.23-0.26% in this patent, Mn:1.8-2.0%, Cr:0.30-0.35, overall carbon equivalent is higher, affects toughness and weldability; After tubulation, homogeneous tube carries out normalizing or modified thermal treatment.
4) Japanese Patent JP58199818A, high-strength oil well manufacture of steel pipe.C:0.28-0.35% in this patent, Mo:0.1-0.3%, V:0.02-0.10, C content is higher, adds noble metal Mo; After tubulation, homogeneous tube carries out normalizing thermal treatment.
5) Japanese Patent JP58199819A, high-strength oil well manufacture of steel pipe.C:0.30-0.35% in this patent, V:0.05-0.09, C content is higher, adds noble metal V; After tubulation, homogeneous tube carries out normalizing thermal treatment.
6) Japanese Patent JP59170223A, normalizing type homogeneous high-strength oil well electricresistance welded steel pipe manufacture method.C:0.25-0.40% in this patent, C content is higher; After tubulation, homogeneous tube carries out normalizing thermal treatment.
7) Japanese Patent JP01225722A, the high-strength electric resistance welded pipe manufacturing method of oil well.In this patent, selectivity adds Nb:0-0.045%, V:0-0.10%; As rolled steel plate (coiled sheet) is N80 rank, and intensity is high is unfavorable for follow-up ERW tubulation; After tubulation, carry out weld seam thermal treatment, the consistency of performance of body and weld seam is poor.
8) Japanese Patent JP07102321A, the manufacture method of the non-thermal treatment Oil Well Pipe of tensile strength 800MPa high strength.C:0.25-0.40% in this patent, V:01-0.10%; As rolled steel plate (coiled sheet) is N80 rank, and intensity is high is unfavorable for follow-up ERW tubulation; After tubulation, carry out weld seam thermal treatment, the consistency of performance of body and weld seam is poor.
Wherein 7), 8) patent is the patent of invention of As rolled N80 straight welding oil annular tube, heat-treat butt welded seam and heat affected zone, different from product of the present invention.And 1), 2), 3), 4), 5), 6) patent and product of the present invention the most approaching, be the patent of invention of manufacturing quenched and tempered state N80Q straight welding oil annular tube, but all have obvious difference with the present invention.
The disclosed straight welding oil annular tube steel of above patent has reached the regulation of the API Spec5CT of API standard, but has following problem: otherwise carbon content is higher, unfavorable to weldability and toughness; Add precious alloy Mo, V, cost is higher; Homogeneous tube normalizing thermal treatment, impelling strength can decline to some extent.And 7) and 8) be the N80 straight welding oil annular tube of As rolled, the higher follow-up ERW tubulation difficulty of coiled sheet performance, a butt welded seam and heat affected zone thermal treatment, the consistency of performance of body and weld seam is poor.
Summary of the invention
The object of the invention is to overcome existing deficiency in above-mentioned prior art, it is J55 rank that a kind of As rolled coiled sheet performance is provided, and after the modified thermal treatment of homogeneous tube, performance is other vertical masonry joint resistance welding (ERW) petroleum casing pipe and manufacture method thereof of N80Q level.
One of technical scheme of the present invention is to provide a kind of N80Q level vertical masonry joint resistance welding (ERW) petroleum casing pipe, its chemical composition (weight, %) proportioning is as follows: C:0.15%-0.20%, Si:0.15%-0.30%, Mn:1.40%-1.80%, P :≤0.020, S :≤0.008%, Ti:0.010%-0.030%, Als:0.02%-0.05%, Nb:0.01%-0.04%, N :≤0.008%, all the other are Fe and inevitable impurity.
Compared with prior art, this programme C content is moderate, and weldability and the impelling strength of coiled sheet are good; With micro-Nb, Ti, replace precious metal Mo, V, reduce cost of alloy; As rolled coiled sheet performance is lower, and follow-up tubulation moulding is easy; Homogeneous tube carries out modified thermal treatment, and performance reaches N80Q rank, has guaranteed the consistence of body and Weld Performance simultaneously.
C: carbon is carbide forming element, is the effective element of proof strength, can improve stability after hardening capacity and thermal treatment, the strength of materials while guaranteeing the long-time tempering of high temperature, and therefore, carbon content is unsuitable too low; But carbon content is too high, will affect impelling strength and the welding property of product, it is considered herein that the oil casing pipe steel for N80Q, it is comparatively suitable that carbon is controlled at 0.15%-0.20%.
Si: can play solution strengthening effect, but its too high levels can make plasticity and the toughness drop of steel, its optimum range is 0.15%-0.30%.
Mn: manganese has solution strengthening effect, can also increase stabilization of austenite, also favourable to improving hardening capacity, effectively guarantees the intensity of steel.But manganese content is excessive, can increase the center segregation tendency of continuously cast bloom, affect the homogeneity of structure of hot-strip, its optimum range is 1.40%-1.80%.
P: phosphorus is harmful element in steel, the cold shortness of increase steel, degenerates welding property, reduces plasticity, and cold-bending property is degenerated, and should control its content≤0.020%.
S: sulphur is harmful element in steel, makes steel produce red brittleness, reduces ductility and the toughness of steel, and welding property is also unfavorable, reduces erosion resistance, for guaranteeing the high cleanliness of molten steel, should control its content≤0.008%.
Nb: niobium can come superheated susceptivity and the temper brittleness of crystal grain thinning and reduction steel by precipitation strength, improve intensity, improve welding property, but too high meeting increases cost of alloy, and suitable scope is 0.01-0.04%.
Ti: titanium is strong nitrogen killer, while adding 0.015% left and right Ti, can when sheet billet continuous casting, form the TiN precipitated phase that high-temperature stable is tiny, this tiny TiN precipitated phase can effectively stop continuously cast bloom the growing up of austenite crystal in heat-processed, to improving the toughness of steel when welding heat affected zone, have obvious effect, suitable scope is 0.010-0.030% simultaneously.
Als: aluminium is conventional reductor adds a small amount of aluminium in steel, can crystal grain thinning, improve impelling strength, and suitable scope is 0.02-0.05%.
Two of technical scheme of the present invention is to provide a kind of manufacture method of N80Q grade of steel straight slit electric resistance welding petroleum casing pipe, comprises hot metal pretreatment, smelting molten steel, external refining, sheet billet continuous casting, rolling, ERW tubulation and the modified thermal treatment of homogeneous tube, it is characterized in that:
1) smelt continuous casting process: hot metal pretreatment; Converter smelting-through top blast or top bottom blowing; External refining-through RH vacuum-treat, the frivolous sulphuring treatment of LF stove and carry out calcium processing to control inclusion morphology and to improve ductility, toughness and the cold-bending property of steel; Sheet billet continuous casting-continuous casting adopts induction stirring or dynamic soft-reduction, to improve the quality of continuous casting steel billet.
2) rolling technology: continuous casting steel billet is heated to 1200-1300 ℃ through process furnace, with adopting two-stage control rolling by hot continuous mill group, first stage start rolling temperature is 1180-1280 ℃, finishing temperature is greater than 980 ℃, subordinate phase start rolling temperature is less than 960 ℃, finishing temperature is 720-840 ℃, rolls rear coiled sheet and with the speed of 6-19 ℃/s, carries out coolingly, carries out coiled sheet batch 470-600 ℃ of temperature.The yield strength that makes As rolled coiled sheet is 440-530MPa, and tensile strength is 550-690MPa.
3) homogeneous tube quenching-and-tempering process: after ERW tubulation, homogeneous tube is heated to 880-950 ℃, more than insulation 30min, shrend; Again homogeneous tube is heated to 550-600 ℃, more than insulation 80min, air cooling tempering.The yield strength that makes modified rear homogeneous tube is 620-720MPa, and tensile strength is 770-840MPa, laterally-10 ℃ of Charpy-V impact power Akv >=50J.
The special feature of technical solution of the present invention is: 1) C content is moderate, and weldability and the impelling strength of coiled sheet are good; 2) with micro-Nb, Ti, replace precious metal Mo, V, reduce cost of alloy; 3) As rolled coiled sheet performance is lower, and follow-up tubulation moulding is easy; 4) homogeneous tube carries out modified thermal treatment, and performance is N80Q rank, has guaranteed the consistence of body and Weld Performance simultaneously.
Embodiment
The present invention is further described by the following embodiment.
The chemical composition of embodiment of the present invention steel is in Table 1.The rolling technology of embodiment of the present invention steel and As rolled mechanical property are in Table 2.The hardening and tempering process of embodiment of the present invention pipe and mechanical property are in Table 3.
The chemical composition (wt, %) of table 1 embodiment of the present invention steel
Embodiment C Si Mn P S Nb Ti Als N
1 0.15 0.15 1.75 0.0075 0.0054 0.032 0.010 0.028 0.0042
2 0.17 0.20 1.54 0.0080 0.0053 0.033 0.020 0.038 0.0051
3 0.20 0.12 1.50 0.0080 0.0054 0.028 0.030 0.049 0.0049
4 0.20 0.19 1.60 0.0097 0.0057 0.032 0.013 0.024 0.0062
5 0.19 0.21 1.46 0.0150 0.0038 0.040 0.010 0.042 0.0045
6 0.18 0.24 1.51 0.0150 0.0033 0.018 0.018 0.035 0.0049
The rolling technology of table 2 embodiment of the present invention steel and As rolled mechanical property
Figure BSA00000282829300061
Hardening and tempering process and the mechanical property of table 3 embodiment of the present invention pipe
Figure BSA00000282829300062
From table 3, adopt Composition Design of the present invention and rolling, homogeneous tube thermal treatment process, the N80Q grade of steel straight slit electric resistance welding petroleum casing pipe of producing, has met the requirement of API SPEC 5CT standard to N80Q level steel pipe.

Claims (3)

1. the manufacture method of a N80Q rank straight slit electric resistance welding petroleum casing pipe, comprise hot metal pretreatment, smelting molten steel, external refining, sheet billet continuous casting, rolling, ERW tubulation and the modified thermal treatment of homogeneous tube, it is characterized in that steel pipe chemical component weight per-cent is: C:0.15%-0.20%, Si:0.15%-0.30%, Mn:1.40%-1.80%, P :≤0.020, S :≤0.008%, Ti:0.010%-0.030%, Als:0.02%-0.05%, Nb:0.010%-0.033%, N :≤0.008%, all the other are Fe and inevitable impurity; In described rolling technology by heating of plate blank to 1200-1300 ℃, through hot continuous rolling unit, adopt two-stage control rolling, first stage start rolling temperature is 1180-1280 ℃, finishing temperature is greater than 980 ℃, subordinate phase start rolling temperature is less than 960 ℃, finishing temperature is 720-810 ℃, rolls rear coiled sheet and with the speed of 6-19 ℃/s, carries out coolingly, carries out coiled sheet batch 470-600 ℃ of temperature; In described homogeneous tube quenching-and-tempering process, homogeneous tube is heated to 880-950 ℃, more than insulation 30min, shrend, reheats 550-600 ℃, and more than insulation 80min, air cooling tempering.
2. the manufacture method of straight slit electric resistance welding petroleum casing pipe according to claim 1, is characterized in that adopting RH vacuum-treat, the frivolous sulphuring treatment of LF stove and calcium to process in described furnace outer refining process.
3. the manufacture method of straight slit electric resistance welding petroleum casing pipe according to claim 1, is characterized in that adopting induction stirring or dynamic soft-reduction in described sheet billet continuous casting technique.
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CN102912230A (en) * 2012-10-23 2013-02-06 鞍钢股份有限公司 690MPa-grade electric resistance welding petroleum sleeve and manufacture method thereof
CN102936687B (en) * 2012-10-29 2014-10-15 武汉钢铁(集团)公司 110ksi-level ERW (electric resistance welding) steel belt for oil casings and production method thereof
CN103147009B (en) * 2012-12-13 2015-03-25 济钢集团有限公司 N80Q steel-grade oil casing and manufacture method thereof
CN103882302B (en) * 2012-12-21 2016-03-02 鞍钢股份有限公司 N80-Q level straight weld oil annular tube steel and manufacture method thereof
CN103469072A (en) * 2013-09-07 2013-12-25 鞍钢股份有限公司 Straight welded oil casing pipe and manufacturing method thereof
CN105695882B (en) * 2014-11-28 2017-10-27 鞍钢股份有限公司 J55 grades of low yield strength ratio electric resistance welding casing steels and its manufacture method
CN111996447A (en) * 2020-08-03 2020-11-27 鞍钢股份有限公司 Steel for large thick-wall high-toughness resistance welding sleeve and manufacturing method thereof
CN113549816B (en) * 2021-06-28 2022-11-18 鞍钢股份有限公司 High-strength high-toughness resistance welding steel for petroleum casing pipe and manufacturing method of casing pipe
CN113817960A (en) * 2021-08-10 2021-12-21 包头钢铁(集团)有限责任公司 N80 petroleum casing pipe steel and preparation method thereof
CN115198186A (en) * 2022-07-05 2022-10-18 鞍钢股份有限公司 High-strength electric resistance welding petroleum casing for deep well and manufacturing method thereof

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