CN106702273B - A kind of economical resistance to H2S corrodes normalizing pipe line steel and production method - Google Patents
A kind of economical resistance to H2S corrodes normalizing pipe line steel and production method Download PDFInfo
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- CN106702273B CN106702273B CN201611073337.0A CN201611073337A CN106702273B CN 106702273 B CN106702273 B CN 106702273B CN 201611073337 A CN201611073337 A CN 201611073337A CN 106702273 B CN106702273 B CN 106702273B
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- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C38/00—Ferrous alloys, e.g. steel alloys
- C22C38/04—Ferrous alloys, e.g. steel alloys containing manganese
-
- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
- C21D8/00—Modifying the physical properties by deformation combined with, or followed by, heat treatment
- C21D8/02—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips
- C21D8/0221—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips characterised by the working steps
- C21D8/0226—Hot rolling
-
- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
- C21D8/00—Modifying the physical properties by deformation combined with, or followed by, heat treatment
- C21D8/02—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips
- C21D8/0247—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips characterised by the heat treatment
- C21D8/0263—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips characterised by the heat treatment following hot rolling
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C38/00—Ferrous alloys, e.g. steel alloys
- C22C38/02—Ferrous alloys, e.g. steel alloys containing silicon
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- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C38/00—Ferrous alloys, e.g. steel alloys
- C22C38/12—Ferrous alloys, e.g. steel alloys containing tungsten, tantalum, molybdenum, vanadium, or niobium
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- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Materials Engineering (AREA)
- Mechanical Engineering (AREA)
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- Organic Chemistry (AREA)
- Physics & Mathematics (AREA)
- Thermal Sciences (AREA)
- Crystallography & Structural Chemistry (AREA)
- Heat Treatment Of Steel (AREA)
Abstract
A kind of economical resistance to H2S corrosion normalizing pipe line steel, chemical component and wt%:C:0.04 ~ 0.07%, Si:0.10 ~ 0.20%, Mn:0.7 ~ 0.9%, P :≤0.01%, S :≤0.002%, Nb 0.06 ~ 0.12%, V 0.04 ~ 0.07%, B≤0.0005, RE≤0.0005.Production stage: slab is heated；Roughing；Finish rolling；It is cooling；It batches；Normalizing.The present invention is except guaranteeing using mechanical property and good weldability, also there is excellent hydrogen sulfide corrosion-resistant performance, crackle is not observed in the case where loaded load is 0.80 × practical yield strength load-up condition, and cost of alloy is simple, it is at low cost to reduce by 20% or more.
Description
Technical field
The present invention relates to a kind of pipe line steel and production methods, particularly belong to a kind of resistance to H2The excellent positive fire tube of S corrosive nature
Line steel and production method.
Background technique
Petroleum, natural gas are the important energy sources of the national economic development, and the specific gravity in energy-consuming increasingly increases.Work as front tube
Road conveying is still petroleum, natural gas long distance delivery mode the most economic, safe and efficient.However, with easy exploitation stone
The exhaustion of oil, natural gas resource, H2The high construction of natural gas fields dynamics of S content just continues to increase.
H2S is most one of the hazardous medium of corrosiveness in oil and natural gas.When pipe line steel is exposed to containing wet H2S
Pumped (conveying) medium in when, H easily occurs for material2S sour corrosion causes to send pipeline catastrophic failure, wherein hydrogen induced cracking (HIC) (HIC) and
Sulfide stress cracking (SSC) (SSCC) is H2The principal mode of S corrosion.
The H contained in China's major part oil gas field2S levels are higher, and the medium of gathering-line pipe conveying is without de-
The petroleum or natural gas of the processing such as salt, dehydration, desulfurization, the pipe line steel of corresponding party, which removes, requires it with good intensity, impact
Except performance and welding performance, preferable anti-H it is also desirable to have2S corrosive nature.Normalizing state pipe line steel is equal because of its microstructure and property
Even characteristic, compared to rolled more suitable for the manufacture of gathering line.The demand of reduction oil-gas transportation cost is considered simultaneously,
Need the resistance to H of exploiting economy type2S corrodes normalizing pipe line steel.
Through retrieving, before making the present invention, Chinese Patent Application No. CN201010235925.6,
The document of CN201510297590.3, CN20160419909.X, CN2012101168133.0, CN201410233997.5, institute
What the normalizing pipeline steel chemical composition being related to was all made of be the component system of Mn in low C or middle C+, while adding appropriate Cr, Ni etc.
Precious alloy, economy is insufficient and does not have corrosion resistance.
Chinese Patent Application No. be CN201210271608.9, CN201610025494.8, CN201310146465.3,
The document of CN201010130911.8, CN201410130811.3, related normalizing pipe line steel use Cu+Cr+Mo+Ni or high
The component system of Cr does not have economy feature.
Summary of the invention
The invention reside in the shortcomings of the prior art is overcome, providing a kind of has high-intensitive, high tenacity and good
Except weldability, also have using controlled rolling and controlled cooling with offline normalizing be heat-treated combine by the way of produce, resistance to H2S corrosive nature
It is excellent, with the low economical resistance to H that 20% or more cost of alloy reduction, hic resistance and SSCC can be made to have excellent performance of cost of alloy2S
Corrode normalizing pipe line steel and production method.
Realize the measure of above-mentioned purpose:
A kind of economical resistance to H2S corrodes normalizing pipe line steel, chemical component and weight percent content are as follows: and C:0.04 ~
0.07%, Si:0.10 ~ 0.20%, Mn:0.7 ~ 0.9%, P :≤0.01%, S :≤0.002%, Nb 0.06 ~ 0.12%, V 0.04 ~
0.07%, B≤0.0005, RE≤0.0005, remaining is Fe and impurity.
Produce a kind of economical resistance to H2The method that S corrodes normalizing pipe line steel, step:
1) slab after continuous casting is heated, controls its heating temperature at 1100 ~ 1150 DEG C；
2) roughing is carried out, and controlling roughing end temp is 1030 ~ 1080 DEG C；
3) finish rolling is carried out, and controls its start rolling temperature and is no more than 950 DEG C, 870 ~ 900 DEG C of finishing temperature control position；
4) it is cooled down, is cooled to coiling temperature under the conditions of 30 ~ 40 DEG C/s of cooling velocity；
5) it is batched, controls coiling temperature at 500 ~ 550 DEG C；
6) normalizing is carried out, and controls normalizing temperature at 890 ~ 920 DEG C, and is carried out at a temperature of this according to 1.5 ~ 2min/mm again
Heat preservation.
Respectively change the effect and mechanism of Element-Level main technique in the present invention:
C:C is most basic, most economical intensified element, effectively improves the strong of steel by solution strengthening and precipitation strength
Degree.It is unobvious to the intensity effect of steel when C content is too low, the plasticity, toughness and weldability of steel can be then reduced when content is too high,
And the banded structure rank in steel can be aggravated.Therefore the content control of C is 0.040 ~ 0.070% in the present invention.
Si:Si improves the intensity of steel mainly with solution strengthening form, while being also the deoxidant element in steel, but content is too low
When strengthening effect it is unobvious, it is again unfavorable to the toughness of steel when too high levels.Therefore in the present invention content control of Si for 0.10 ~
0.20%。
Mn:Mn is solution strengthening element important in steel, conducive to the intensity and low-temperature flexibility for improving steel.But its too high levels
When, it will lead to that component segregation in its steel is serious, and then hard crisp pearlite or M/A banded structure in steel is promoted to be formed, deteriorate
The resistance to H of steel2S corrosive nature.Meanwhile high Mn content is easy to promote the generation of MnS ribbon field trash, becomes diffusible hydrogen in steel
Aggregation, be easy to induce hydrogen induced cracking (HIC).Therefore the content control of Mn is 0.7 ~ 0.9% in the present invention.
Nb: Nb has strong Grain Refinement Effect and medium precipitation strength effect in course of hot rolling, can postpone Austria
Family name's body recrystallization, leads to the refinement of austenite grain and phase-change product and improves the obdurability of steel.In normalizing procedure, it is dissolved in steel
Nb element by solute drageffect prevent austenite grain excessively growing up, degree of grain refinement when hot rolling can be made to obtain
To largely heredity, and Nb element is precipitated in the form of second phase particles in normalizing cooling procedure, improves the strong of normalized steel
Degree.Therefore the control of Nb content is 0.06 ~ 0.12% in the present invention.
V:V is important microalloy element, has strong precipitating reinforcing effect, can effectively improve the intensive properties of steel
Can, but its too high levels then can cause the impact flexibility of steel to be remarkably decreased.Therefore in the present invention V content control 0.04 ~
0.07%。
P, sulphur S:P can reduce the low-temperature flexibility of steel, deteriorate welding performance, and P is easy to be segregated in steel, promotes band-like group
The generation knitted is unfavorable for the resistance to H of steel2S etching characteristic.S is easy to be mingled with Mn formation strip MnS, is influencing the same of steel toughness
When, hydrogen atom tends to assemble at the tip MnS, to induce H2S corrosion cracking.Therefore the present invention should reduce containing for P, S to the greatest extent
Amount is to reduce its adverse effect to steel, and the content control of P is P≤0.010%, and the content control of S is S≤0.0020%.
In view of user is to the common demands of pipeline steel chemical composition, B and RE element is not deliberately added in the present invention, and want
Ask B≤0.0005%, RE≤0.0005%.
The present invention is to obtain to take into account the intensity and corrosion resistance of normalizing pipe line steel, except optimizing to chemical component
Outside, it is also directed in hot rolling stage (roughing, finish rolling, cooling etc.) and the production technology in normalizing stage (temperature, time etc.)
Property design.Specific mentality of designing is as follows:
1) the low Mn system of low C+ is used to reduce the formation trend of banded structure in steel, while utilizing the fast quickly cooling after hot rolling
But technology inhibits the diffusion and Local enrichment of phase transformation stage C element, improves the corrosion resistance of steel.
2) produce using the low C high Nb technology of TMCP+, it is close by sufficient recrystallization softening and non-recrystallization dislocation
Degree accumulation promotes the Nb element being dissolved in austenite in the form of NbC in dislocation and grain boundaries disperse educt, and then is normalizing rank
Section austenite grain forming core provides advantage, to realize that the refinement of austenite grain and the obdurability of normalized steel improve.
3) accurately control the control of cold stage cooling velocity and final cooling temperature, it is ensured that the V element in steel is with tiny, disperse
Form be sufficiently precipitated, and then nucleation site is provided in normalizing stage austenitization, realize Austenite Grain Refinement and
Normalized steel obdurability improves.
4) normalizing temperature and soaking time are controlled, had not only guaranteed complete austenitizing but also excessive grain is avoided to grow up, in order to avoid dislike
Change the intensity and toughness of normalized steel.
Ton steel cost can reduce by 15% to the present invention compared with prior art, have high-intensitive, high tenacity and good solderable
Except connecing property, i.e. yield strength Rt0.5 >=245MPa, tensile strength Rm>=415MPa, -20 DEG C of ballistic work KV2The full ruler of >=180J(
Very little specification), -20 DEG C of DWTT section shearing rate SA >=90%.
Meanwhile the present invention has excellent resistance to H in NACE solution A2S corrosive nature.It is embodied in, according to NACE
0284 standard of TM carries out HIC inspection, the crack length rate CLR of normalizing pipe line steel sample section, crack thickness rate in solution A
CTR, crackle the area ratio CSR value are 0, i.e. sample section flawless；According to 0177 standard of NACE TM, in solution A respectively
SSCC inspection is carried out using four-point bending method, normalizing pipeline steel curved beam is 0.80SYMS(nominal-ultimate strength in loaded load) it carries
Do not observe crackle under the conditions of lotus.
Detailed description of the invention
Fig. 1 is the metallographic structure figure of steel plate of the present invention.
Specific embodiment
The present invention is described in detail below:
Table 1 is the chemical component list of various embodiments of the present invention and comparative example；
Table 2 is the main technologic parameters list of various embodiments of the present invention and comparative example；
Table 3 is various embodiments of the present invention and comparative example mechanical property and resistance to H2S corrosive nature list；
Table 4 is the embodiment of the present invention and the important cost of alloy comparison list of similar patent Example.
Various embodiments of the present invention follow the steps below production:
1) slab after continuous casting is heated, controls its heating temperature at 1100 ~ 1150 DEG C；
2) roughing is carried out, and controlling roughing end temp is 1030 ~ 1080 DEG C；
3) finish rolling is carried out, and controls its start rolling temperature and is no more than 950 DEG C, 870 ~ 900 DEG C of finishing temperature control position；
4) it is cooled down, is cooled to coiling temperature under the conditions of 30 ~ 40 DEG C/s of cooling velocity；
5) it is batched, controls coiling temperature at 500 ~ 550 DEG C；
6) normalizing is carried out, and controls normalizing temperature at 890 ~ 920 DEG C, and is carried out at a temperature of this according to 1.5 ~ 2min/mm again
Heat preservation.
1 various embodiments of the present invention of table and comparison steel chemical composition comparative example (wt%)
The main technologic parameters comparative example of 2 embodiment of the present invention of table and comparative example
3 various embodiments of the present invention of table and comparative example mechanical property and resistance to H2S corrosive nature list
4 embodiment of the present invention of table is compared to the important cost of alloy of similar patent Example
From 3 data of table it is found that the mechanical property and HIC, SSCC performance of the embodiment of the present invention are superior to comparative example.
Since the present invention is not added with the expensive alloying elements such as Cu, Ni, Cr, Mo, compared with similar proprietary alloy cost, ton
Steel cost reduces by 20% or more.
Present embodiment is only the best example, not to the restricted implementation of technical solution of the present invention.
Claims (1)
1. producing a kind of economical resistance to H2The method that S corrodes normalizing pipe line steel, step:
1) slab after continuous casting is heated, controls its heating temperature at 1100 ~ 1150 DEG C；
2) roughing is carried out, and controlling roughing end temp is 1065 ~ 1080 DEG C；
3) finish rolling is carried out, and controls its start rolling temperature at 937 ~ 950 DEG C, 880 ~ 900 DEG C of finishing temperature control position；
4) it is cooled down, is cooled to coiling temperature under the conditions of 30 ~ 40 DEG C/s of cooling velocity；
5) it is batched, controls coiling temperature at 500 ~ 550 DEG C；
6) normalizing is carried out, and controls normalizing temperature and is kept the temperature at 890 ~ 920 DEG C, and again at a temperature of this according to 1.5 ~ 2min/mm；
The economical resistance to H2S corrodes normalizing pipe line steel, chemical component and weight percent content are as follows: C:0.04 ~ 0.07%,
Si:0.10 ~ 0.20%, Mn:0.7 ~ 0.9%, P :≤0.01%, S :≤0.002%, Nb 0.06 ~ 0.12%, V 0.04 ~ 0.07%,
Remaining is Fe and impurity.
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| Application Number | Priority Date | Filing Date | Title |
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| CN201611073337.0A CN106702273B (en) | 2016-11-29 | 2016-11-29 | A kind of economical resistance to H2S corrodes normalizing pipe line steel and production method |
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| CN201611073337.0A CN106702273B (en) | 2016-11-29 | 2016-11-29 | A kind of economical resistance to H2S corrodes normalizing pipe line steel and production method |
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| CN106702273B true CN106702273B (en) | 2019-04-09 |
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Families Citing this family (3)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN110499454B (en) * | 2018-05-16 | 2021-07-16 | 宝山钢铁股份有限公司 | Economical sulfate reducing bacteria corrosion-resistant seamless gathering and transportation pipeline and manufacturing method thereof |
| CN111254362B (en) * | 2020-03-31 | 2021-01-19 | 湖南华菱湘潭钢铁有限公司 | Production method of Gr.B-grade normalizing pipeline steel |
| CN111500941B (en) * | 2020-05-15 | 2021-06-29 | 佛山科学技术学院 | HIC (hydrogen induced cracking) resistant pipeline steel based on structure regulation and preparation method thereof |
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| CN103649351A (en) * | 2011-06-30 | 2014-03-19 | 杰富意钢铁株式会社 | High strength hot-rolled steel sheet for welded steel line pipe having excellent souring resistance, and method for producing same |
| CN105695863A (en) * | 2016-02-04 | 2016-06-22 | 首钢总公司 | Hot-rolled coiled plate for natural gas delivery pipeline and manufacturing method thereof |
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| JP2009001834A (en) * | 2007-06-19 | 2009-01-08 | Jfe Steel Kk | Ferritic stainless steel superior in high-temperature strength, heat resistance and workability |
| JP5200600B2 (en) * | 2008-03-18 | 2013-06-05 | Ｊｆｅスチール株式会社 | Manufacturing method of high strength and low yield ratio steel |
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