CN102864396B - Low-alloy-steel seamless steel tube for nuclear power and production method thereof - Google Patents
Low-alloy-steel seamless steel tube for nuclear power and production method thereof Download PDFInfo
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- CN102864396B CN102864396B CN201210359268.5A CN201210359268A CN102864396B CN 102864396 B CN102864396 B CN 102864396B CN 201210359268 A CN201210359268 A CN 201210359268A CN 102864396 B CN102864396 B CN 102864396B
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Abstract
The invention provides a low-alloy-steel seamless steel tube for nuclear power and a production method thereof. The production method includes: a, smelting a tube blank; b, rolling the tube blank into a seamless steel tube; and c, performing heat treatment at normalizing temperature of 930-950 DEG C and tempering temperature of 670-690 DEG C, wherein the tube blank comprises chemical components including, by weight percent, 0.09-0.13% of C, 0.65-0.85% of Si, 0.35-0.55% of Mn, 1.15-1.35% of Cr, 0.48-0.60% of Mo, 0-0.010% of Sb, 0-0.010% of Bi, 0-0.015% of P, 0-0.010% of S, and the balance of Fe and unavoidable impurities, and the tube blank is at the initial heating furnace temperature of 1240-1260 DEG C before rolling. The low-alloy-steel seamless steel tube fully satisfies the technical requirements of seamless steel tubes for third-generation nuclear power units in terms of normal-temperature mechanical property, normal-temperature impact property, 350 DEG C high-temperature tensile property and steel purity.
Description
Technical field
The present invention relates to weldless steel tube technical field, more particularly, relate to a kind of generation Ⅲ nuclear power low alloy steel weldless steel tube and production method thereof.
Background technology
The principle of design of generation Ⅲ nuclear power unit, on the basis of the tachnical storage adopting s-generation nuclear power generating sets to accumulate and service experience, for its weak point, adopt through the feasible new technology of exploitation checking further, significantly to improve its security and economy.The core melt probability of AP1000 and radioactivity discharge approximately low 2 magnitudes of likelihood ratio existing s-generation nuclear power generating sets in a large number, fully demonstrated the superiority of Generation Ⅲ, namely the risk of a two generations nuclear power generating sets generation major accident will be equivalent to the risk of 100 multiple stage generation Ⅲ nuclear power unit generation major accidents.Generation Ⅲ have employed the prevention of a lot of major accident and mitigation strategy, to reduce the probability that core melt and a large amount of radioactivity outwards discharge, major accident is separated as design basis using gentle for prevention, the possibility occurred drops to extremely low, meets the requirement of the existing nuclear safety codes of China and international safety standard completely.
Therefore, nuclear power pipe is very high to tube material specification of quality, and require to adopt different weldless steel tubes according to purposes, the low alloy steel weldless steel tube that generation Ⅲ nuclear power unit adopts, requires that it has higher-strength and excellent toughness and good ambient temperature mechanical properties, normal temperature impact property and 350 DEG C of high temperature tensile properties.
Summary of the invention
For prior art above shortcomings, an object of the present invention is to provide a kind of generation Ⅲ nuclear power low alloy steel weldless steel tube, this weldless steel tube has good ambient temperature mechanical properties, normal temperature impact property and 350 DEG C of high temperature tensile properties, can meet technical requirements and the service requirements at generation Ⅲ nuclear power station.
An aspect of of the present present invention provides a kind of production method of nuclear power low alloy steel weldless steel tube, described production method comprises step: a, smelt pipe, the chemical composition of described pipe is by weight percentage: C 0.09 ~ 0.13%, Si 0.65 ~ 0.85%, Mn 0.35 ~ 0.55%, Cr 1.15 ~ 1.35%, Mo 0.48 ~ 0.60%, Cu 0 ~ 0.10%, As 0 ~ 0.015%, Sn 0 ~ 0.010%, Pb 0 ~ 0.010%, Sb 0 ~ 0.010%, Bi 0 ~ 0.010%, P 0 ~ 0.015%, the Fe of S 0 ~ 0.010% and surplus and inevitable impurity, b, billet production is become weldless steel tube, before rolling, the temperature going out process furnace of pipe is 1240 ~ 1260 DEG C, c, heat-treat the weldless steel tube after rolling, heat treated normalizing temperature is 930 ~ 950 DEG C, and tempering temperature is 670 ~ 690 DEG C.
Preferably, the chemical composition of described pipe is by weight percentage: the Fe of C 0.12%, Si 0.75%, Mn 0.45%, Cr 1.25%, Mo 0.54%, Cu 0.08%, As 0.013%, Sn 0.006%, Pb 0.003%, Sb 0.005%, Bi 0.004%, P 0.010%, S 0.005% and surplus and inevitable impurity.
Another aspect provides a kind of nuclear power low alloy steel weldless steel tube, the chemical composition of described low alloy steel weldless steel tube is by weight percentage: the Fe of C 0.09 ~ 0.13%, Si 0.65 ~ 0.85%, Mn 0.35 ~ 0.55%, Cr 1.15 ~ 1.35%, Mo 0.48 ~ 0.60%, Cu 0 ~ 0.10%, As 0 ~ 0.015%, Sn 0 ~ 0.010%, Pb 0 ~ 0.010%, Sb 0 ~ 0.010%, Bi 0 ~ 0.010%, P 0 ~ 0.015%, S 0 ~ 0.010% and surplus and inevitable impurity.
Preferably, the chemical composition of described low alloy steel weldless steel tube is by weight percentage: the Fe of C 0.12%, Si 0.75%, Mn 0.45%, Cr 1.25%, Mo 0.54%, Cu 0.08%, As 0.013%, Sn 0.006%, Pb 0.003%, Sb 0.005%, Bi 0.004%, P 0.010%, S 0.005% and surplus and inevitable impurity.
Compared with prior art, beneficial effect of the present invention comprises: provide a kind of nuclear power low alloy steel weldless steel tube, the ambient temperature mechanical properties of this low alloy steel weldless steel tube, normal temperature impact property and 350 DEG C of high temperature tensile properties and purity of steel, meet the technical requirements of generation Ⅲ nuclear power station unit weldless steel tube completely.Specifically, the ballistic work that described low alloy steel weldless steel tube yield strength is at normal temperatures not less than 340MPa, tensile strength is not less than 485MPa, unit elongation is not less than 35%, 20 DEG C is not less than 230J, and its at 350 DEG C yield strength is not less than 250MPa, tensile strength is not less than 485MPa, unit elongation is not less than 24%.
Embodiment
Hereinafter, nuclear power low alloy steel weldless steel tube of the present invention and production method thereof will be described in detail in conjunction with exemplary embodiment.
The production method of nuclear power low alloy steel weldless steel tube according to an aspect of the present invention comprises step: a, smelting pipe, and the chemical composition of described pipe is by weight percentage: the Fe of C 0.09 ~ 0.13%, Si 0.65 ~ 0.85%, Mn 0.35 ~ 0.55%, Cr 1.15 ~ 1.35%, Mo 0.48 ~ 0.60%, Cu 0 ~ 0.10%, As 0 ~ 0.015%, Sn.0 ~ 0.010%, Pb 0 ~ 0.010%, Sb 0 ~ 0.010%, Bi 0 ~ 0.010%, P 0 ~ 0.015%, S 0 ~ 0.010% and surplus and inevitable impurity; B, billet production is become weldless steel tube, during rolling, the tapping temperature of pipe is 1240 ~ 1260 DEG C; C, heat-treat the steel pipe after rolling, heat treated normalizing temperature is 930 ~ 950 DEG C, and tempering temperature is 670 ~ 690 DEG C.
Preferably, the chemical composition of described pipe is by weight percentage: the Fe of C 0.12%, Si 0.75%, Mn 0.45%, Cr 1.25%, Mo 0.54%, Cu 0.08%, As 0.013%, Sn 0.006%, Pb 0.003%, Sb 0.005%, Bi 0.004%, P 0.010%, S 0.005% and surplus and inevitable impurity.
The chemical composition of nuclear power low alloy steel weldless steel tube is according to a further aspect of the invention by weight percentage: the Fe of C 0.09 ~ 0.13%, Si 0.65 ~ 0.85%, Mn 0.35 ~ 0.55%, Cr 1.15 ~ 1.35%, Mo 0.48 ~ 0.60%, Cu 0 ~ 0.10%, As 0 ~ 0.015%, Sn 0 ~ 0.010%, Pb 0 ~ 0.010%, Sb 0 ~ 0.010%, Bi 0 ~ 0.010%, P 0 ~ 0.015%, S 0 ~ 0.010% and surplus and inevitable impurity.
Further, in order to make steel pipe purity higher, meet normal temperature impact property and 350 DEG C of high temperature tensile properties of steel pipe use, preferably, the chemical composition of described low alloy steel weldless steel tube is by weight percentage: the Fe of C 0.12%, Si 0.75%, Mn 0.45%, Cr 1.25%, Mo 0.54%, Cu 0.08%, As 0.013%, Sn 0.008%, Pb 0.003%, Sb 0.005%, Bi 0.004%, P 0.010%, S 0.005% and surplus and inevitable impurity.
If C, Cr are low higher than the impact toughness at room temperature of chemical composition set upper limit weldless steel tube, unit elongation is low, lower than the lower limit that chemical composition specifies, tensile strength and the yield strength of weldless steel tube are low; Harmful element As, Sn, Pb, Sb, Bi easily separate out at crystal boundary in tubulation process, make grain boundary separation form microcrack, affects steel pipe inner quality, while As content high in Nuclear power plants operational process because its decay is harmful; P, S height reduces purity of steel, reduces impelling strength, affects the use safety of Nuclear power plants.Therefore the chemical composition ranges selected, had both ensured the product performance of generation Ⅲ nuclear power station low alloy steel weldless steel tube, ensured again the use properties of product, provided good guarantee to the safe operation of Nuclear power plants.
Normalizing temperature of the present invention, at 930 ~ 950 DEG C, is conducive to alloying element solid solution and diffusion, is evenly distributed in austenite, with the uniform Carbide Precipitation of disperse, reaches highly malleablized effect, ensures tensile strength and good impelling strength.If normalizing temperature is too low, is unfavorable for abundant austenitizing and diffusion of alloy elements evenly, affects normalizing effect; Temperature is too high, problem that is overheated, coarse grains easily occurs, produces detrimentally affect to steel tube performance.Should high tempering be adopted after normalizing treatment, obtain ferrite, perlite and tempering bainite, meet higher intensity and good plasticity and toughness energy requirement.The AC of chemical composition ranges of the present invention
1be about 731 DEG C, tempering temperature is too high, will occur that Heating temperature is more than AC
1there is " excess temperature tempering " problem in transformation temperature; Temperature is too low, then do not reach the processing requirement of high tempering, can not meet the structure and properties requirement of product.
In one exemplary embodiment of the present invention, the production method of nuclear power low alloy steel weldless steel tube also can realize in the following manner:
A, smelting pipe: smelt pipe, the chemical composition of pipe is by weight percentage: C 0.09 ~ 0.13%, Si 0.65 ~ 0.85%, Mn 0.35 ~ 0.55%, Cr 1.15 ~ 1.35%, Mo0.48 ~ 0.60%, Cu 0 ~ 0.10%, As 0 ~ 0.015%, Sn 0 ~ 0.010%, Pb 0 ~ 0.010%, Sb 0 ~ 0.010%, Bi 0 ~ 0.010%, P 0 ~ 0.015%, S 0 ~ 0.010%, surplus are Fe and inevitable impurity;
B, steel pipe rolling: billet production is become weldless steel tube, the tapping temperature 1240 ~ 1260 DEG C of pipe during rolling;
C, Steel Pipe Heat process: the steel pipe after rolling is heat-treated, heat treatment normalizing temperature is 940 ± 10 DEG C, and tempering temperature is 680 ± 10 DEG C, ensures the mechanical property of product.
All the other steps of producing above-mentioned weldless steel tube are identical with the production method of conventional weldless steel tube.
Below in conjunction with concrete example, exemplary illustration is carried out to the present invention.
1, pipe is smelted
By smelting and continuous casting, obtain the pipe of example 1 to 3.The chemical composition of the pipe of example 1 to 3 is as shown in table 1.
The chemical composition (wt%) of the pipe of table 1 example 1 to 3
In smelting, external refining, casting cycle, operate in strict accordance with specification, make the chemical composition of steel even, steel is pure, to guarantee the performance of steel pipe.
2, steel pipe rolling
The various processing parameters such as pipe Heating temperature, finishing temperature are controlled, to meet steel tube performance index in the operation of rolling.Main technologic parameters is as follows:
Ring furnace furnace temperature must ensure blank temperature of coming out of the stove: 1240 ~ 1260 DEG C.
3, Steel Pipe Heat process
Steel Pipe Heat process adopts normalizing to add tempering process, and normalizing temperature is 940 ± 10 DEG C, and tempering temperature is 680 ± 10 DEG C.
4, steel tube performance detects
The performance test results of the nuclear power low alloy steel weldless steel tube of example 1-3 is in table 2 ~ table 4.
The normal tensile property of the weldless steel tube of table 2 example 1-3, impact property
| Example | Yield strength/MPa | Tensile strength/MPa | Unit elongation/% | Impact temperature/DEG C | Ballistic work/J |
| 1 | 355 | 505 | 48 | 20 | 230 |
| 2 | 365 | 500 | 37 | 20 | 286 |
| 3 | 345 | 490 | 40 | 20 | 246 |
350 DEG C of high temperature tensile properties of the weldless steel tube of table 3 example 1-3
| Example | Yield strength/MPa | Tensile strength/MPa | Unit elongation/% |
| 1 | 265 | 505 | 26 |
| 2 | 285 | 490 | 24 |
| 3 | 255 | 515 | 28 |
The nonmetal inclusion that the weldless steel tube of table 4 example 1-3 is stable checks rank
As can be seen from table 2 ~ table 4, the stable performance of used in nuclear power station low alloy steel weldless steel tube of the present invention, steel is pure, meets the performance requriements of generation Ⅲ nuclear power station low alloy steel weldless steel tube product completely, and has good normal temperature impact property and 350 DEG C of high temperature tensile properties.Specifically, the ballistic work that used in nuclear power station low alloy steel weldless steel tube of the present invention yield strength is at normal temperatures not less than 340MPa, tensile strength is not less than 485MPa, unit elongation is not less than 35%, 20 DEG C is not less than 230J, and its at 350 DEG C yield strength is not less than 250MPa, tensile strength is not less than 485MPa, unit elongation is not less than 24%.
In sum, the ambient temperature mechanical properties of nuclear power low alloy steel weldless steel tube of the present invention, normal temperature impact property and 350 DEG C of high temperature tensile properties and purity of steel, meet the technical requirements of generation Ⅲ nuclear power station unit weldless steel tube completely.The present invention is that generation Ⅲ nuclear power station unit weldless steel tube provides a kind of selection newly, has broad application prospects.
Although describe the present invention in conjunction with exemplary embodiment above, those of ordinary skill in the art should be clear, when not departing from the spirit and scope of claim, can carry out various amendment to above-described embodiment.
Claims (5)
1. a nuclear power production method for low alloy steel weldless steel tube, is characterized in that, described production method comprises step:
A, smelting pipe, the chemical composition of described pipe is by weight percentage: the Fe of C0.09 ~ 0.13%, Si0.65 ~ 0.85%, Mn0.35 ~ 0.55%, Cr1.15 ~ 1.35%, Mo0.48 ~ 0.60%, Cu0.08 ~ 0.10%, As0 ~ 0.015%, Sn0 ~ 0.010%, Pb0 ~ 0.010%, Sb0 ~ 0.010%, Bi0 ~ 0.010%, P0 ~ 0.015%, S0 ~ 0.010% and surplus and inevitable impurity;
B, billet production is become weldless steel tube, before rolling, the temperature going out process furnace of pipe is 1240 ~ 1260 DEG C;
C, heat-treat the weldless steel tube after rolling, heat treated normalizing temperature is 930 ~ 950 DEG C, and tempering temperature is 670 ~ 690 DEG C.
2. the production method of nuclear power low alloy steel weldless steel tube according to claim 1, it is characterized in that, the chemical composition of described pipe is by weight percentage: the Fe of C0.12%, Si0.75%, Mn0.45%, Cr1.25%, Mo0.54%, Cu0.08%, As0.013%, Sn0.006%, Pb0.003%, Sb0.005%, Bi0.004%, P0.010%, S0.005% and surplus and inevitable impurity.
3. a nuclear power low alloy steel weldless steel tube, it is characterized in that, the chemical composition of described low alloy steel weldless steel tube is by weight percentage: the Fe of C0.09 ~ 0.13%, Si0.65 ~ 0.85%, Mn0.35 ~ 0.55%, Cr1.15 ~ 1.35%, Mo0.48 ~ 0.60%, Cu0.08 ~ 0.10%, As0 ~ 0.015%, Sn0 ~ 0.010%, Pb0 ~ 0.010%, Sb0 ~ 0.010%, Bi0 ~ 0.010%, P0 ~ 0.015%, S0 ~ 0.010% and surplus and inevitable impurity.
4. nuclear power low alloy steel weldless steel tube according to claim 3, it is characterized in that, the chemical composition of described low alloy steel weldless steel tube is by weight percentage: the Fe of C0.12%, Si0.75%, Mn0.45%, Cr1.25%, Mo0.54%, Cu0.08%, As0.013%, Sn0.006%, Pb0.003%, Sb0.005%, Bi0.004%, P0.010%, S0.005% and surplus and inevitable impurity.
5. nuclear power low alloy steel weldless steel tube according to claim 3, it is characterized in that, the ballistic work that described low alloy steel weldless steel tube yield strength is at normal temperatures not less than 340MPa, tensile strength is not less than 485MPa, unit elongation is not less than 35%, 20 DEG C is not less than 230J, and its at 350 DEG C yield strength is not less than 250MPa, tensile strength is not less than 485MPa, unit elongation is not less than 24%.
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| CN103741062B (en) * | 2013-12-23 | 2016-11-09 | 马鞍山市盈天钢业有限公司 | A kind of seamless steel tube material for nuclear power and preparation method thereof |
| CN103924161A (en) * | 2014-04-21 | 2014-07-16 | 中广核工程有限公司 | Main steam and main water supply pipeline in a conventional island of nuclear power plants and preparation method thereof |
| CN104195431B (en) * | 2014-07-29 | 2016-09-14 | 锐展(铜陵)科技有限公司 | A kind of yield strength is more than 1000MPa level superhigh tenacity low-alloy steel and manufacture method thereof |
| CN104294166B (en) * | 2014-10-08 | 2016-06-01 | 天津钢管集团股份有限公司 | The carbon steel nuclear power weldless steel tube of chromium nickel microalloying and production method thereof |
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| CN101769403A (en) * | 2009-12-23 | 2010-07-07 | 攀枝花新钢钒股份有限公司 | Seamless steel tube for nuclear power and production method thereof |
| CN102365376A (en) * | 2009-03-30 | 2012-02-29 | 住友金属工业株式会社 | Method for producing seamless steel pipe |
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| JP3214351B2 (en) * | 1996-04-09 | 2001-10-02 | 住友金属工業株式会社 | Method for producing Cr-Mo based seamless steel pipe excellent in high temperature strength |
| JP3326783B2 (en) * | 1996-04-12 | 2002-09-24 | 住友金属工業株式会社 | Manufacturing method of low alloy seamless steel pipe with excellent high temperature strength |
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| CN102365376A (en) * | 2009-03-30 | 2012-02-29 | 住友金属工业株式会社 | Method for producing seamless steel pipe |
| CN101769403A (en) * | 2009-12-23 | 2010-07-07 | 攀枝花新钢钒股份有限公司 | Seamless steel tube for nuclear power and production method thereof |
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