CN102912230A - 690MPa-grade electric resistance welding petroleum sleeve and manufacture method thereof - Google Patents
690MPa-grade electric resistance welding petroleum sleeve and manufacture method thereof Download PDFInfo
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- CN102912230A CN102912230A CN201210411195XA CN201210411195A CN102912230A CN 102912230 A CN102912230 A CN 102912230A CN 201210411195X A CN201210411195X A CN 201210411195XA CN 201210411195 A CN201210411195 A CN 201210411195A CN 102912230 A CN102912230 A CN 102912230A
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Abstract
The invention provides a 690MPa-grade electric resistance welding petroleum sleeve and a manufacture method of the 690MPa-grade electric resistance welding petroleum sleeve. The 690MPa-grade electric resistance welding petroleum sleeve is prepared by the following chemical components in percentage by weight: 0.15 to 0.23% of C, 0.15 to 0.30% of Si, 1.25 to 1.58% of Mn, not greater than 0.020% of P, not greater than 0.008% of S, 0.010 to 0.030% of Ti, 0.02 to 0.05% of Als, 0.020 to 0.048% of V, not greater than 0.008% of N, and the balance of Fe. The manufacture method comprises steps as follows: smelting, continuously casting, rolling, preparing a pipe, and thermally processing the whole pipe; after heated to reach a temperature of 1180 to 1280 DEG C, a slab blank is rolled in two stages, wherein initial rolling in the first stage is at the temperature of 1130 to 1280 DEG C, and final rolling is at the temperature more than 960 DEG C; and the initial rolling in the second stage is at the temperature less than 950 DEG C, and the final rolling temperature is 760 to 850 DEG C; then rolled slab blank is rolled at the temperature of 8 to 18 DEG C per second after rolling, and coiled at the temperature of 560 to 640 DEG C; after being manufactured, the whole pipe processed by heating reach the temperature of 880 to 940 DEG C, maintaining the temperature for more than 30 minutes; quenching by water, then heating to reach the temperature of 520 to 560 DEG C, maintaining the temperature for more than 25 minutes, cooling in air, and tempering. The manufacture method is low in cost of an alloy; a coiled plate is high in welding performance and impact toughness, so that the pipe can be easily manufactured and formed in a later period.
Description
Technical field
The invention belongs to the high-strength low-alloy steel technical field, relate to a kind of ERW(ERW, Electric Resistance Weld, resistance welding) sleeve pipe and manufacture method thereof, be particularly related to that a kind of tensile strength is other N80Q petroleum casing pipe and manufacture method thereof of 690MPa level among the API SPEC 5CT, its As rolled steel band performance is the J55 grade of steel, and the modified rear performance of homogeneous tube is the 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, and it is many to spend, and is requisite construction material in the oil-gas field drill operation.The ERW sleeve pipe is compared with seamless tube, has that wall thickness is even, dimensional precision is high, the perforation performance is good, anti-squeezing ruin the significant advantages such as ability is strong, cost is low.
API SPEC 5CT regulation: the yield strength of N80Q rank steel pipe between 552-785MPa, tensile strength 〉=689MPa, elongation 〉=19%; Horizontal Charpy-V impact power 〉=24J in the time of 21 ℃.Because this steel-grade bushing intensity is higher, tensile strength reaches 690MPa, if the steel band of As rolled reaches this intensity, certainly will need to add a large amount of precious alloys and improve intensity, increase cost of alloy, and the mother metal of steel pipe can't reach consistent with welding seam tissue capability; This intensity has reached the limit of ERW unit tubulation ability simultaneously, if directly adopt the hot rolled strip tubulation of this intensity, the moulding difficulty of steel pipe is large, and the dimensional precision of steel pipe and circularity are difficult to guarantee.Therefore, can adopt the lower J55 hot rolled strip of As rolled intensity to carry out the ERW welding tube-making, then carry out homogeneous tube thermal treatment, make the final performance of steel pipe reach the N80Q stratification levels.And weld seam carries out identical thermal treatment process with body, and 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.
Below for making the prior art of quenched and tempered state N80Q straight welding oil annular tube:
1) Chinese patent CN101376943A, 80ksi grade of steel straight welding oil annular tube steel, sleeve pipe and manufacture method.Contain C:0.15%-0.35% in its composition, Mn:0.8%-1.5%, Mo:0.1%-0.5% carries out the modified thermal treatment of homogeneous tube behind the tubulation.Add noble element Mo in this patent, cost of alloy is high.
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 the composition, Mn:1.4%-1.6%, Cr:0.3%-0.6%, Nb:0.12%-0.14%, V:0.08%-0.12% carries out the modified thermal treatment of homogeneous tube behind the tubulation.Add noble element Nb, V in this patent, and content is high, cost of alloy is high.
3) Japanese Patent JP58199818A, the high-strength oil well manufacture of steel pipe.C:0.28%-0.35% in the composition, Mn:1.40%-2.00%, Mo:0.1%-0.3%, V:0.02%-0.10%, homogeneous tube carries out normalizing thermal treatment behind the tubulation.Add noble element Mo in this patent, cost of alloy is high; C content is higher, affects steel band impelling strength.
4) Japanese Patent JP58093821A, the oil well manufacture method of electricresistance welded steel pipe.C:0.23%-0.26% in the composition, Mn:1.8%-2.0%, Cr:0.30%-0.35%, V:0.03%-0.10%, homogeneous tube carries out normalizing or modified thermal treatment behind the tubulation.C content is higher in this patent, affects the impelling strength of steel band; Simultaneously Mn, Cr content are also high, cause carbon equivalent higher (Ceq:0.60%-0.68%), and the weldability of steel band is bad.
5) Japanese Patent JP58199819A, the high-strength oil well manufacture of steel pipe.C:0.30%-0.35% in the composition, Mn:1.60%-2.00%, V:0.05%-0.09%, homogeneous tube carries out normalizing thermal treatment behind the tubulation.C content is higher in this patent, affects the impelling strength of steel band; V content is high, and cost of alloy is high; Mn content is also high simultaneously, causes carbon equivalent higher (Ceq:0.58%-0.70%), and the weldability of steel band is bad.
6) Japanese Patent JP59170223A, normalizing type homogeneous high-strength oil well electricresistance welded steel pipe manufacture method.C:0.25%-0.40% in the composition, Mn:1.20%-1.80%, V:0.01-0.20%, selectivity adds Mo:0.05%-0.50%, Nb:0.01%-0.055%, B:0.0001%-0.0002%, homogeneous tube carries out normalizing thermal treatment behind the tubulation.C content is higher in this patent, affects the impelling strength of steel band; When V reaches 0.18%, do not add Mo, when V≤0.12%, add Mo 〉=0.22%, the cost of alloy of V or Mo is high.
7) paper " thermal treatment is on the impact of N80 level ERW casing steel microstructure and property ", C:0.13% in the composition, Mn:1.49%, Si:0.26%, Mo:0.25%, Cr:0.66%, Ni:0.25%, Nb:0.041%, S:0.04%, Ti:0.023%, P:0.01%.Add precious alloy elements Mo, Ni, Nb and a large amount of Cr in this paper, cost of alloy is high.
8) paper " research of N80 level ERW oil casing pipe steel continuous cooling transformation behavior ", C:0.200%-0.212% in the composition, Mn:1.000%-1.070%, Si:0.18%-0.25%, Nb+Mo+Cr:0.242%-0.580%, Ti+Al:0.015%-0.050%.Add precious alloy elements Mo, Nb in this paper, cost of alloy is high.
More than in disclosed patent or the document, the more precious alloy Mo of the interpolation that has, Nb, V, cost of alloy is high; The carbon content that has is higher, and steel band toughness is bad; The carbon equivalent that has is higher, and the steel band weldability is bad.
Summary of the invention
The object of the invention is to overcome existing deficiency in the above-mentioned prior art, a kind of tensile strength 690MPa level high-frequency electric resistance welded petroleum casing pipe and manufacture method thereof are provided, carbon adds a small amount of V design in particularly adopting, As rolled steel band performance is the J55 rank, and performance is other vertical masonry joint resistance welding (ERW) petroleum casing pipe and manufacture method thereof of N80Q level after the modified thermal treatment of homogeneous tube.
One of technical solution of the present invention is to propose a kind of 690MPa level electric resistance welding petroleum sleeve pipe, its chemical ingredients (weight percent) proportioning is as follows: C:0.15%-0.23%, Si:0.15%-0.30%, Mn:1.25%-1.58%, P :≤0.020%, S :≤0.008%, Ti:0.010%-0.030%, Als:0.02%-0.05%, V:0.020%-0.048%, N :≤0.008%, all the other are Fe and inevitable impurity.
C: carbon is carbide forming element, is the effective element of proof strength, can improve stability after hardening capacity and the thermal treatment, the strength of materials when guaranteeing the long-time tempering of high temperature, and therefore, carbon content should not be excessively low; But the too high impelling strength that will affect product of carbon content, its optimum range is 0.15%-0.23%.
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, and is 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, affects the homogeneity of structure of hot-strip, brings negative impact to weldquality, and its optimum range is 1.25%-1.58%.
P: phosphorus is harmful element in the steel, increases the cold shortness of steel, and welding property is degenerated, and reduces plasticity, and cold-bending property is degenerated, and should control its content≤0.020%.
S: sulphur is harmful element in the steel, makes steel produce red brittleness, reduces ductility and the toughness of steel, and welding property is also unfavorable, for guaranteeing the high cleanliness of molten steel, should control its content≤0.008%.
V: the carbonitride of vanadium is evenly separated out with the small and dispersed form in ferrite, can significantly improve yield strength and the tensile strength of material, but too high meeting increases cost of alloy, and suitable scope is 0.020%-0.048%.
Ti: titanium is strong nitrogen killer, when adding 0.015% left and right sides Ti, can when sheet billet continuous casting, form the tiny TiN precipitated phase of high-temperature stable, this tiny TiN precipitated phase can effectively stop continuously cast bloom the growing up of austenite crystal in heat-processed, simultaneously the toughness of improving steel when welding heat affected zone is had obvious effect, suitable scope is 0.010%-0.030%.
Als: aluminium is the reductor of commonly using, and adds a small amount of aluminium in steel, but crystal grain thinning improves impelling strength, and suitable scope is 0.02%-0.05%.
N: solid solution nitrogen has the strong effect of pinning dislocation, and toughness is had detrimentally affect, should control its content≤0.008%
Two of technical solution of the present invention is the manufacture method that propose a kind of 690MPa level electric resistance welding petroleum sleeve pipe, comprise hot metal pretreatment, smelting molten steel, external refining and sheet billet continuous casting, continuously cast bloom reheat, rolling, cool off, batch, tubulation and homogeneous tube thermal treatment.It is characterized in that:
1) smelt continuous casting process: hot metal pretreatment, converter smelting---through top blast or top bottom blowing, the frivolous sulphuring treatment of LF stove and carry out ductility, toughness and the cold-bending property that calcium is processed to control inclusion morphology and improved 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 1180-1280 ℃ through process furnace, with adopting two-stage control rolling by the hot continuous mill group, the fs start rolling temperature is 1130-1280 ℃, finishing temperature is greater than 960 ℃, the subordinate phase start rolling temperature is less than 950 ℃, finishing temperature is 760-850 ℃, rolls rear steel band and cools off with the speed of 8-18 ℃/s, carries out steel strip coiling 560-640 ℃ of temperature.The yield strength of As rolled steel band is 379-552MPa, and tensile strength is 520-690MPa.
3) welded tube processed: steel band carries out high frequency/medium frequency electric welding resistance through the ERW unit, and to make intensity be other steel pipe of J55 level.
4) homogeneous tube quenching-and-tempering process: behind the ERW tubulation, homogeneous tube is heated to 880-940 ℃, more than the insulation 30min, and shrend; Again homogeneous tube is heated to 520-560 ℃, more than the insulation 25min, the air cooling tempering.The yield strength of modified rear homogeneous tube is 610-735MPa, and tensile strength is 730-805MPa, 21 ℃ of horizontal Charpy-V impact powers (3 sample averages) Akv 〉=24J.
Compared with prior art, the beneficial effect of technical solution of the present invention: 1) replace noble metal Mo, Nb with a small amount of V, reduce cost of alloy; 2) C content and carbon equivalent (0.35%-0.51%) are moderate, and weldability and the impelling strength of coiled sheet are good; 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 the N80Q rank, has guaranteed the consistence of body and Weld Performance.
Embodiment
The present invention is described further below by embodiment.
The chemical ingredients of embodiment of the invention steel sees Table 1, and heating, rolling process for cooling see Table 2, and mechanical property sees Table 3.
The chemical ingredients (wt, %) of table 1 embodiment of the invention steel
| Embodiment | C | Si | Mn | P | S | V | Ti | Als | N |
| 1 | 0.22 | 0.22 | 1.54 | 0.008 | 0.008 | 0.027 | 0.010 | 0.023 | 0.0036 |
| 2 | 0.18 | 0.25 | 1.54 | 0.012 | 0.003 | 0.031 | 0.017 | 0.028 | 0.0047 |
| 3 | 0.15 | 0.22 | 1.57 | 0.010 | 0.007 | 0.020 | 0.020 | 0.033 | 0.0043 |
| 4 | 0.18 | 0.24 | 1.29 | 0.004 | 0.006 | 0.047 | 0.018 | 0.023 | 0.0033 |
| 5 | 0.20 | 0.26 | 1.35 | 0.006 | 0.006 | 0.041 | 0.025 | 0.038 | 0.0041 |
| 6 | 0.16 | 0.21 | 1.47 | 0.005 | 0.004 | 0.022 | 0.020 | 0.040 | 0.0036 |
The heating of table 2 embodiment of the invention, rolling technology and As rolled mechanical property
Table 3 embodiment of the invention hardening and tempering process and mechanical property
By as seen from Table 3, adopt Composition Design of the present invention and rolling, welded tube, homogeneous tube thermal treatment process, the tensile strength 690MPa level straight slit electric resistance welding petroleum casing pipe of producing satisfies API SPEC 5CT standard to the requirement of N80Q level steel pipe.
Claims (4)
1. 690MPa level electric resistance welding petroleum sleeve pipe, it is characterized in that its chemical component weight per-cent is: C:0.15%-0.23%, Si:0.15%-0.30%, Mn:1.25%-1.58%, P :≤0.020%, S :≤0.008%, Ti:0.010%-0.030%, Als:0.02%-0.05%, V:0.020%-0.048%, N :≤0.008%, all the other are Fe and inevitable impurity.
2. the manufacture method of the described 690MPa level of claim 1 an electric resistance welding petroleum sleeve pipe, comprise hot metal pretreatment, smelting molten steel, external refining, sheet billet continuous casting, rolling, tubulation and homogeneous tube thermal treatment, it is characterized in that describedly rollingly being: continuous casting steel billet is heated to 1180-1280 ℃, hot rolling adopts two-stage control rolling, the fs start rolling temperature is 1130-1280 ℃, finishing temperature is greater than 960 ℃, the subordinate phase start rolling temperature is less than 950 ℃, finishing temperature is 760-850 ℃, roll rear steel band with the speed cooling of 8-18 ℃/s, coiling temperature is 560-640 ℃; Described homogeneous tube thermal treatment is: homogeneous tube is heated to 880-940 ℃, more than the insulation 30min, and shrend; Again homogeneous tube is heated to 520-560 ℃, more than the insulation 25min, the air cooling tempering.
3. the manufacture method of described 690MPa level electric resistance welding petroleum sleeve pipe according to claim 2 is characterized in that described external refining, adopts the LF stove to carry out frivolous sulphuring treatment and calcium is processed.
4. the manufacture method of described 690MPa level electric resistance welding petroleum sleeve pipe according to claim 2 is characterized in that described sheet billet continuous casting adopts induction stirring or dynamic soft-reduction.
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Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104561774A (en) * | 2013-10-10 | 2015-04-29 | 鞍钢股份有限公司 | P110-level straight-seam welding petroleum casing pipe and manufacturing method thereof |
| CN105506455A (en) * | 2015-12-21 | 2016-04-20 | 武钢集团昆明钢铁股份有限公司 | Forging steel molten steel used for producing valve body and valve cover for ore pulp delivery pipeline and smelting process thereof |
| CN106319359A (en) * | 2015-06-29 | 2017-01-11 | 鞍钢股份有限公司 | M65-grade electric resistance welding casing pipe and manufacturing method thereof |
| CN107523750A (en) * | 2017-08-31 | 2017-12-29 | 达力普石油专用管有限公司 | A kind of deep-well petroleum casing pipe and preparation method thereof |
| CN108296461A (en) * | 2018-01-18 | 2018-07-20 | 新疆八钢铁股份有限公司 | Oil casing pipe steel J55 steel-making continuous casting production methods |
| CN110735091A (en) * | 2019-11-05 | 2020-01-31 | 天津钢管制造有限公司 | Method for improving impact power of J K55 steel-grade oil well pipe by treating alloy steel with micro-titanium |
| 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 |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5735625A (en) * | 1980-08-12 | 1982-02-26 | Kawasaki Steel Corp | Manufacture of high tensile steel pipe with superior toughness at low temperature |
| CN102409229A (en) * | 2010-09-21 | 2012-04-11 | 鞍钢股份有限公司 | N80Q grade straight seam ERW (Electric Resistance Welding) petroleum casing and manufacturing method thereof |
-
2012
- 2012-10-23 CN CN201210411195XA patent/CN102912230A/en active Pending
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5735625A (en) * | 1980-08-12 | 1982-02-26 | Kawasaki Steel Corp | Manufacture of high tensile steel pipe with superior toughness at low temperature |
| CN102409229A (en) * | 2010-09-21 | 2012-04-11 | 鞍钢股份有限公司 | N80Q grade straight seam ERW (Electric Resistance Welding) petroleum casing and manufacturing method thereof |
Cited By (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104561774A (en) * | 2013-10-10 | 2015-04-29 | 鞍钢股份有限公司 | P110-level straight-seam welding petroleum casing pipe and manufacturing method thereof |
| CN106319359A (en) * | 2015-06-29 | 2017-01-11 | 鞍钢股份有限公司 | M65-grade electric resistance welding casing pipe and manufacturing method thereof |
| CN105506455A (en) * | 2015-12-21 | 2016-04-20 | 武钢集团昆明钢铁股份有限公司 | Forging steel molten steel used for producing valve body and valve cover for ore pulp delivery pipeline and smelting process thereof |
| CN107523750A (en) * | 2017-08-31 | 2017-12-29 | 达力普石油专用管有限公司 | A kind of deep-well petroleum casing pipe and preparation method thereof |
| CN107523750B (en) * | 2017-08-31 | 2019-07-09 | 达力普石油专用管有限公司 | A kind of deep-well petroleum casing pipe and preparation method thereof |
| CN108296461A (en) * | 2018-01-18 | 2018-07-20 | 新疆八钢铁股份有限公司 | Oil casing pipe steel J55 steel-making continuous casting production methods |
| CN110735091A (en) * | 2019-11-05 | 2020-01-31 | 天津钢管制造有限公司 | Method for improving impact power of J K55 steel-grade oil well pipe by treating alloy steel with micro-titanium |
| 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 |
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