CN115369323A - 800 MPa-grade hydrogen-induced crack resistant container steel plate and production method thereof - Google Patents
800 MPa-grade hydrogen-induced crack resistant container steel plate and production method thereof Download PDFInfo
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Abstract
The invention relates to an 800MPa grade hydrogen-induced crack resistant container steel plate and a production method thereof, wherein the steel plate comprises the following chemical components of 0.2-0.25% of C, 0.15-0.35% of Si, 0.8-0.85% of Mn, less than or equal to 0.003% of P, less than or equal to 0.001% of S, mo:0.03 to 0.05 percent of Fe, 0.2 to 0.3 percent of V, 0.0003 to 0.002 percent of Ca, 0.002 to 0.03 percent of Als and the balance of Fe and impurities. Reducing steel plate structure segregation by controlling the contents of C and Mn in the steel, and changing the shape of inclusions in the steel by adding Ca; alloy elements V and Mo are added to refine grains, so that the steel plate has good toughness, and the steel plate has good comprehensive performance after normalizing and simulated postweld heat treatment through precipitation strengthening; by adopting a heat treatment mode of staged rolling and normalizing weak cooling/short-time normalizing, the steel plate product is ensured to have uniform grain size and high strength in the whole thickness direction, and has excellent hydrogen-induced crack resistance.
Description
Technical Field
The invention relates to the technical field of steel plates for pressure vessels, in particular to a 800 MPa-grade steel plate for a vessel with excellent hydrogen-induced crack resistance and a production method thereof.
Background
Hydrogen sulfide is one of the most corrosive harmful media in petroleum and natural gas, and the stress corrosion of the hydrogen sulfide to a transmission pipeline accounts for a large proportion in the process of conveying the natural gas. When used in a wet hydrogen sulfide environment, can cause Hydrogen Blistering (HB), hydrogen Induced Cracking (HIC), and stress-directed hydrogen induced cracking (SOHIC) within carbon steels. In an acidic environment containing hydrogen sulfide or the like, hydrogen generated by corrosion intrudes into steel to generate cracks, which become Hydrogen Induced Cracks (HIC). In previous studies, it was found that the hydrogen-induced resistance of steel is greatly related to the strength of steel. The higher the strength of the steel sheet, the worse the hydrogen resistance of the steel tends to be. At present, the HIC-resistant steel plate is mainly used for pipeline steel and container steel, and the container steel not only needs to consider the normalizing performance, but also needs to consider the subsequent welding and repairing, so that various performances of the steel plate subjected to the simulated postweld heat treatment still meet the requirements.
With the increasing economic development and energy demand, the reserve volume of petroleum and natural gas as strategic materials becomes one of the indexes for measuring the sustainable development capability of the economy of each country, and China also builds large-scale petroleum and liquefied natural gas storage tanks in succession. Therefore, the steel plate for the large liquefied petroleum balloon tank has excellent comprehensive performance, the strength and the toughness of the steel plate are superior to those of conventional steel, the welding performance and the hydrogen sulfide stress corrosion resistance of the steel plate are similar to or even superior to those of the conventional steel, and the cost of the steel plate is lower than that of a material with the same performance abroad.
Chinese patent application with application number CN201210055848.5 discloses 'steel for hydrogen induced cracking resistant pressure vessels and a manufacturing method thereof', relating to a low-carbon high-strength low-alloy thick steel plate with tensile strength of more than or equal to 620MPa, wherein the steel plate comprises the following components in percentage by weight: 0.15 to 0.25%, si:0.10 to 0.30%, mn: 1.00-1.60%, P: less than or equal to 0.012 percent, less than or equal to 0.002 percent of S, mo: 0.35-0.60%, V is less than or equal to 0.05%, ni:0.20 to 0.80%, ca:0.0013 to 0.0045% and Al: 0.002-0.050%, and the steel plate is processed by quenching and tempering, but the steel plate is produced by the heat treatment process with higher cost.
Chinese patent application with the application number of CN201310497333.5 discloses' a steel plate for a 450 MPa-grade hydrogen induced cracking resistant pressure vessel and a production method thereof, wherein the steel plate comprises the following components in percentage by weight: 0.13 to 0.14%, si:0.20 to 0.30%, mn:0.90 to 0.95 percent, less than or equal to 0.008 percent of P and less than or equal to 0.001 percent of S, and finally the tensile strength of the steel plate reaches 450 to 464MPa by adopting two stages of controlled rolling with the thickness of 2.0 times, a controlled rolling and controlled cooling process of accelerated cooling at the cooling speed of 10 to 12 ℃ per second after rolling and an off-line normalizing heat treatment process. The strength grade of the produced steel plate is low, and the long-term simulation post-welding heat treatment performance and other aspects are not required.
Chinese patent application with publication number CN105603304A discloses 'a thick steel plate for Q370R pressure vessel with good HIC and SSCC resistance and a manufacturing method thereof', which adopts normalizing and water cooling heat treatment process to produce a vessel steel plate with maximum thickness of 60mm, and makes the steel plate have good HIC and SSCC resistance through reasonable component design. In order to improve the strength of the steel plate, the design of high Mn (1.40-1.62%) is adopted in the examples. However, mn element and S element can easily form MnS inclusion to become a hydrogen trap, and the risk of hydrogen induced cracking is increased; meanwhile, the adopted heat treatment process of water cooling after normalizing causes the nonuniformity of the structure in the thickness direction due to the difference of the cooling speed. In 6 examples, 3 examples have cracks in the hydrogen induced cracking resistance test results, and the stability of the HIC resistance of the steel plate is relatively poor. The maximum steel plate thickness in the embodiment is only 60mm, and the use requirement of a large pressure vessel in the petrochemical industry cannot be met.
In view of the above circumstances, it is highly desirable to develop a high strength steel plate for pressure vessels having excellent hydrogen induced cracking resistance through a novel composition design and a coupled process.
Disclosure of Invention
The invention provides an 800 MPa-grade hydrogen-induced crack resistant container steel plate and a production method thereof, wherein the steel plate structure segregation is reduced by controlling the contents of C and Mn in the steel, and the shape of inclusions in the steel is changed by adding Ca; alloy elements V and Mo are added to refine grains, so that the steel plate has good toughness, and the steel plate has good comprehensive performance after normalizing and simulated postweld heat treatment through precipitation strengthening; the production process matched with the components of the steel plate adopts a staged rolling and normalizing weak cooling/short-time normalizing heat treatment mode, ensures that the finished steel plate has uniform grain size and high strength in the whole thickness direction, and has excellent hydrogen induced cracking resistance.
In order to achieve the purpose, the invention adopts the following technical scheme:
an 800MPa grade hydrogen-induced crack resistant container steel plate comprises the following chemical components by weight percent of 0.2-0.25% of C, 0.15-0.35% of Si, 0.8-0.85% of Mn, less than or equal to 0.003% of P, less than or equal to 0.001% of S, mo:0.03 to 0.05 percent of Fe, 0.2 to 0.3 percent of V, 0.0003 to 0.002 percent of Ca, 0.002 to 0.003 percent of Als, and the balance of Fe and inevitable impurities.
A production method of an 800 MPa-grade hydrogen-induced crack resistant container steel plate comprises the steps of smelting, continuous casting, heating, rolling and heat treatment; the method comprises the following specific steps:
1) And (3) continuous casting process: the casting temperature of the molten steel of the tundish is less than or equal to 1560 ℃, an electromagnetic stirring or continuous casting billet soft reduction process is adopted, and the reduction rate is controlled to be 6-9%;
2) A heating procedure: the heating temperature of the continuous casting billet is 1150-1200 ℃, and the soaking time is 1-3 h;
3) A rolling procedure: a two-stage controlled rolling process is adopted; wherein the final rolling temperature in the first stage is more than or equal to 1050 ℃, and the single-pass reduction rate is 8-11%; the initial rolling temperature of the second stage is more than or equal to 970 ℃, and the single-pass reduction rate is 5-8%;
4) A heat treatment process: the thickness of the finished steel plate is 40-100 mm; selecting different heat treatment processes for the rolled steel plate according to the thickness; wherein t is more than or equal to 40mm and less than or equal to 60mm, and t is the thickness of the steel plate, and the steel plate with t is more than or equal to 60mm and less than or equal to 100mm adopts a normalizing weak cold heat treatment process, and the steel plate with t is more than or equal to 60mm and less than or equal to 100mm adopts a short-time normalizing heat treatment process.
Furthermore, the smelting process adopts the smelting process of electric furnace smelting and VOD vacuum treatment.
Further, in the heat treatment process, the normalizing weak cold heat treatment process comprises the following steps: the heat treatment temperature is controlled to be 880-890 ℃, the temperature rising rate is 1.1-1.3.min/mm, the net heat preservation time is 0.5-0.6 min/mm, the steel is discharged from the furnace for weak cooling after reaching the temperature, and the cooling speed is 1.6-2.0 ℃/s; the temperature of the red returning is 330-340 ℃.
Further, in the heat treatment process, the short time normalizing heat treatment process comprises the following steps: the heat treatment temperature is controlled between 860 and 880 ℃, the heating rate is 1.2 to 1.4min/mm, the steel is discharged from the furnace for air cooling after reaching the temperature, and the total furnace time is less than or equal to 2 hours.
Furthermore, the microstructure of the finished steel plate is ferrite, pearlite and a small amount of bainite which is uniformly dispersed.
Further, the properties of the finished steel sheet are as follows: the yield strength is 444-453 MPa, the tensile strength is 806-828 MPa, and the elongation after fracture is more than or equal to 24 percent; charpy impact AV at-20 ℃ for 3 samples 2 The average value is more than or equal to 242J, b =2a, and d =3a is qualified in a 180 DEG cold bending test; and (4) performing a hydrogen induced cracking test according to GB/T8650-2006, and evaluating the product to be qualified according to NACE TM0284 'evaluation method for hydrogen induced cracking resistance of pipeline steel and pressure vessel steel'.
Compared with the prior art, the invention has the beneficial effects that:
1) The design aspect of steel grade components: the composition design is simple and reasonable, in order to ensure the hydrogen-induced crack resistance of the steel plate, the segregation degree of the steel plate is ensured to be lighter by reasonably controlling the contents of C and Mn in the steel, and the shape of inclusions in the steel is changed by adding Ca; in order to ensure that the steel plate has good obdurability, alloy elements V and Mo are added into the steel, crystal grains are refined, and the steel plate is ensured to have good comprehensive performance after being subjected to normalizing and simulated postweld heat treatment through precipitation strengthening;
2) In the aspect of production process: the small-deformation rolling is performed by adopting multi-pass rolling, so that the grain structure is favorably refined; by adopting a heat treatment mode of staged rolling and normalizing weak cooling/short-time normalizing, the steel plate product is ensured to have uniform grain size and high strength in the whole thickness direction, and has excellent hydrogen induced cracking resistance.
Drawings
FIG. 1 is a metallographic structure photograph of an 800MPa grade hydrogen-induced cracking resistant steel plate for a container according to the invention.
Detailed Description
The invention relates to an 800 MPa-grade hydrogen-induced crack resistant container steel plate, which comprises the following chemical components in percentage by weight of 0.2-0.25% of C, 0.15-0.35% of Si, 0.8-0.85% of Mn, less than or equal to 0.003% of P, less than or equal to 0.001% of S, mo:0.03 to 0.05 percent of Fe, 0.2 to 0.3 percent of V, 0.0003 to 0.002 percent of Ca, 0.002 to 0.003 percent of Als, and the balance of Fe and inevitable impurities.
The invention relates to a production method of an 800 MPa-grade hydrogen-induced crack resistant container steel plate, which comprises the production processes of smelting, continuous casting, heating, rolling and heat treatment; the method comprises the following specific steps:
1) And (3) continuous casting process: the pouring temperature of the molten steel in the tundish is less than or equal to 1560 ℃, an electromagnetic stirring or continuous casting billet soft reduction process is adopted, and the reduction rate is controlled to be 6-9%;
2) A heating procedure: the heating temperature of the continuous casting billet is 1150-1200 ℃, and the soaking time is 1-3 h;
3) A rolling procedure: a two-stage controlled rolling process is adopted; wherein the final rolling temperature in the first stage is more than or equal to 1050 ℃, and the single-pass reduction rate is 8-11%; the second-stage initial rolling temperature is more than or equal to 970 ℃, and the single-pass reduction rate is 5-8%;
4) A heat treatment process: the thickness of the finished steel plate is 40-100 mm; selecting different heat treatment processes for the rolled steel plate according to the thickness; wherein t is more than or equal to 40mm and less than or equal to 60mm, and t is the thickness of the steel plate, and the steel plate with t is more than or equal to 60mm and less than or equal to 100mm adopts a normalizing weak cold heat treatment process, and the steel plate with t is more than or equal to 60mm and less than or equal to 100mm adopts a short-time normalizing heat treatment process.
Furthermore, the smelting process adopts the smelting process of electric furnace smelting and VOD vacuum treatment.
Further, in the heat treatment process, the normalizing weak cold heat treatment process comprises the following steps: the heat treatment temperature is controlled to be 880-890 ℃, the temperature rising rate is 1.1-1.3.min/mm, the net heat preservation time is 0.5-0.6 min/mm, the steel is discharged from the furnace for weak cooling after reaching the temperature, and the cooling speed is 1.6-2.0 ℃/s; the temperature of the red returning is 330-340 ℃.
Further, in the heat treatment process, the short time normalizing heat treatment process comprises the following steps: the heat treatment temperature is controlled between 860 and 880 ℃, the heating rate is 1.2 to 1.4min/mm, the steel is discharged from the furnace for air cooling after reaching the temperature, and the total furnace time is less than or equal to 2 hours.
Furthermore, the microstructure of the finished steel plate is ferrite, pearlite and a small amount of bainite which is uniformly dispersed.
Further, the properties of the finished steel sheet are as follows: the yield strength is 444-453 MPa, the tensile strength is 806-828 MPa, and the elongation after fracture is more than or equal to 24 percent; charpy impact AV at-20 ℃ for 3 samples 2 The average value is not less than 242J, b =2a, and d =3a is qualified in a 180-degree cold bending test; and (4) performing a hydrogen induced cracking test according to GB/T8650-2006, and evaluating the product to be qualified according to NACE TM0284 'evaluation method for hydrogen induced cracking resistance of pipeline steel and pressure vessel steel'.
The invention relates to a 800 MPa-grade hydrogen-induced crack resistant container steel plate which comprises the following chemical components in design and action principle:
c often forms carbide with other alloy elements in steel, and plays a role in strengthening the steel. From the viewpoint of ensuring the strength of the steel sheet, it is desirable that the C content be maintained at a high level, but a high C content tends to cause segregation in the steel, resulting in a significant decrease in the ductile property of the steel sheet. The invention solves the problem by adopting VC/N refined crystal grains. Therefore, on the premise of ensuring the strength of the steel plate, the content of C is controlled to be 0.2-0.25%.
Si has deoxidation and desulfurization effects in steel, and can improve the strength of a steel sheet by solid solution strengthening. Si is an inexpensive alloy element, and addition of an appropriate amount of Si to steel can improve the hardness and strength of ferrite in steel. Si increases the elastic limit, yield strength and yield ratio, and fatigue strength and fatigue ratio of steel, and increases strength to some extent, improving localized corrosion resistance. However, since the impact toughness of the heat affected zone is negatively affected if the Si content is high, the Si content is limited to 0.35% to 0.50% in the present invention.
Mn element is a common desulfurizer in steel, and Mn is easy to form MnS inclusion with S; hard phase martensite and bainite with high strength and low toughness, which are generated by Mn segregation in steel, can increase the cracking tendency after welding and have adverse effects on hydrogen cracking resistance, so that the Mn content is not easy to be too high. The invention comprehensively considers the factors of the strength, the toughness and the hydrogen induced cracking resistance of the steel plate, and limits the Mn content to 0.8-0.85 percent.
P and S are brittle elements in steel and elements which are easy to segregate, so that the lower the content of P and S, the better the content of P and S. The content of P and S is respectively controlled below 0.003 percent and below 0.001 percent in the invention, considering the steel-making operability, the steel-making cost, the satisfaction of the use requirement and other factors.
Mo: is a weak solid solution strengthening element, has the main function of increasing the supercooling capability of austenite in steel, thereby refining the structure, obtaining the strengthening effect and having good influence on impact toughness and brittle transition temperature. In addition, mo has obvious positive influence on the high-temperature-resistant long-time PWHT performance; however, mo adversely affects the weldability of the steel sheet, and is a noble metal and therefore expensive. Therefore, the content of Mo is controlled to be 0.03-0.05 percent in the invention.
V: the main element in the steel of the present invention is a strong carbonitride forming element. First, V is an element far to the left from iron in the periodic table, and tends to form stable carbide (VC), and the formed titanium carbide is hardly dissolved during heating, and effectively suppresses the expansion of grain boundaries, strongly hinders the growth of austenite grains, and promotes the formation of ferrite, and therefore the steel sheet is less likely to be overheated during heat treatment heating, which is advantageous for the heat treatment operation. Second, V can fix the N element in steel. The content of the Ti element is reasonably controlled, so that the content of V (C, N) in the alloy is accurately controlled. During the rolling process, a certain amount of deformation energy storage can be generated on the steel plate rolled in the austenite region, and the deformation energy storage of different degrees can generate different degrees of influence on the dynamics of V (C, N) precipitation in austenite. In the experiment, the VC particles are promoted to be separated out at the high-temperature stage and the low-temperature stage of an austenite region respectively by increasing deformation energy storage, so that the recrystallization of austenite can be better inhibited, and the growth of austenite grains is prevented. Meanwhile, the critical nucleation size of VC in an austenite region, particularly a high-temperature region, can be greatly reduced, the precipitation strengthening effect of VC is improved, and the aim of improving the strength of a steel plate and ensuring the toughness is fulfilled. The stable VC plays a role in fixing C, reduces the reaction of free C and H in steel, namely reduces the generation of hazardous substances such as methane and the like, reduces the decarburization, bulging and cracking tendency of the steel plate, and ensures the excellent hydrogen-induced cracking resistance of the steel plate. However, the research shows that the excessive V can cause abnormal growth of crystal grains, so the invention controls the content of V to be in the range of 0.2-0.3%.
Ca: the sulfide morphology in steel is controlled, and this has the effect of suppressing formation of MnS by formation of CaS. In order to obtain this effect, the Ca content needs to be 0.0003% or more. When the Ca content exceeds 0.005%, the size of CaS formed becomes too large, the brittleness also increases, and the Ca easily becomes a starting point of a fracture crack source. Therefore, the Ca content is limited to 0.0003% to 0.002% in the present invention.
And Als: as a deoxidizing element in steel, alN is formed in the steel, crystal grains can be effectively refined, and the content of the AlN-refined steel is controlled to be 0.002% -0.003%.
The invention relates to a production method of an 800 MPa-grade hydrogen-induced crack resistant container steel plate, which comprises the working procedures of smelting, continuous casting, heating, rolling, heat treatment and the like, and the specific design principle is as follows:
1. smelting by adopting an electric furnace smelting and VOD vacuum treatment process.
2. The continuous casting process is adopted, the process key point is to control the casting temperature, namely the casting temperature of the molten steel in the tundish is less than or equal to 1560 ℃, and the original cast structure can be refined by low-temperature casting. In order to control the center segregation and the porosity of the continuous casting billet, an electromagnetic stirring or continuous casting billet soft reduction process is adopted, wherein the reduction rate is controlled to be 6-9%.
3. The heating temperature of the continuous casting billet is 1150-1200 ℃, and the soaking time is 1-3 h. When the heating temperature is lower than 1150 ℃, coarse precipitates in the continuous casting billet cannot be dissolved, the austenitization of a steel plate is incomplete, and the finish rolling temperature in the first stage cannot be guaranteed; when the heating temperature is higher than 1200 ℃, fine precipitates in the continuous casting slab are easily re-dissolved and grains are excessively grown.
3. The rolling of the continuous casting billet adopts a two-stage controlled rolling process. The final rolling temperature in the first stage is more than or equal to 1050 ℃, the rapid rolling is carried out by adopting large deformation amount in the first stage, the single-pass reduction rate is 8-11%, and the complete dynamic recrystallization of the near surface of the steel plate is ensured; the initial rolling temperature of the two stages is more than or equal to 970 ℃, the rapid rolling is carried out by adopting small deformation in the stage, the single-pass reduction rate is 5-8%, and the near surface of the steel plate is ensured not to be recrystallized.
4. The steel plate after rolling adopts two processes of normalizing weak cooling and short-time normalizing according to the plate thickness specification. Wherein the steel plate with the thickness of 40-60 mm is subjected to normalizing weak cooling, and the steel plate with the thickness of 60-100 mm is subjected to short-time normalizing heat treatment. The short-time normalizing heat treatment process comprises the steps of heating at 860-880 ℃, heating at a rate of 1.2-1.4 min/mm, discharging from the furnace for air cooling after reaching the temperature, and keeping the total time in the furnace for 1-1.2 h. The normalizing weak cold heat treatment process includes controlling the heat treatment temperature at 880-890 deg.c, raising the temperature rate at 1.1-1.3.min/mm, maintaining the net heat preservation time at 0.5-0.6 min/mm, and returning to red temperature of 330-340 deg.c.
The following examples are carried out on the premise of the technical scheme of the invention, and detailed embodiments and specific operation procedures are given, but the scope of the invention is not limited to the following examples.
[ examples ] A method for producing a compound
Table 1 shows chemical compositions of the steel plates, table 2 shows continuous casting and rolling process parameters of the steel plates, table 3 shows post-rolling heat treatment process parameters of the steel plates, table 4 shows simulated post-welding heat treatment mechanical properties of the steel plates, table 5 shows grain size and non-metallic inclusion test results, and table 6 shows hydrogen induced cracking resistance test results of the steel plates.
TABLE 1 Steel plate chemical composition (wt%)
| Examples | C | Si | Mn | P | S | Mo | V | Ca | Als |
| 1 | 0.21 | 0.16 | 0.81 | 0.0028 | 0.0008 | 0.035 | 0.26 | 0.00036 | 0.0023 |
| 2 | 0.20 | 0.34 | 0.83 | 0.0015 | 0.0005 | 0.041 | 0.29 | 0.00042 | 0.0021 |
| 3 | 0.20 | 0.29 | 0.85 | 0.0019 | 0.0009 | 0.038 | 0.30 | 0.00036 | 0.0020 |
| 4 | 0.23 | 0.22 | 0.85 | 0.0010 | 0.0010 | 0.045 | 0.20 | 0.001 | 0.0026 |
| 5 | 0.25 | 0.32 | 0.82 | 0.0019 | 0.0007 | 0.039 | 0.28 | 0.0011 | 0.0024 |
| 6 | 0.24 | 0.35 | 0.83 | 0.0020 | 0.0008 | 0.048 | 0.25 | 0.0012 | 0.0023 |
TABLE 2 continuous casting and Rolling Process parameters of Steel plates
TABLE 3 Heat treatment Process parameters of the Steel sheets
TABLE 4 mechanical Properties of simulated postweld heat treatment of steel plates
In table 4, reL is yield strength, rm is tensile strength, a is elongation after fracture; in the cold bend test, b is the specimen width, a is the nominal thickness, and d is the bend core diameter.
TABLE 5 grain size and non-metallic inclusion test results
TABLE 6 test results of hydrogen induced cracking resistance of steel sheets
FIG. 1 is a photograph showing the metallographic structure of a steel sheet produced in example 1, wherein the steel sheet has a structure of ferrite + pearlite + a small amount of bainite uniformly dispersed therein, and the degree of structure segregation in the steel is low.
The above description is only for the preferred embodiment of the present invention, but the scope of the present invention is not limited thereto, and any person skilled in the art should be considered to be within the technical scope of the present invention, and the technical solutions and the inventive concepts thereof according to the present invention should be equivalent or changed within the scope of the present invention.
Claims (7)
1. An 800 MPa-grade hydrogen-induced crack resistant container steel plate is characterized in that the steel plate comprises the following chemical components by weight percent of 0.2-0.25% of C, 0.15-0.35% of Si, 0.8-0.85% of Mn, less than or equal to 0.003% of P, less than or equal to 0.001% of S, mo:0.03 to 0.05 percent of Fe, 0.2 to 0.3 percent of V, 0.0003 to 0.002 percent of Ca, 0.002 to 0.003 percent of Als, and the balance of Fe and inevitable impurities.
2. The method for producing the 800 MPa-grade hydrogen-induced crack resistant container steel plate as claimed in claim 1, wherein the production process of the steel plate comprises smelting, continuous casting, heating, rolling and heat treatment; the method comprises the following specific steps:
1) And (3) continuous casting process: the casting temperature of the molten steel of the tundish is less than or equal to 1560 ℃, an electromagnetic stirring or continuous casting billet soft reduction process is adopted, and the reduction rate is controlled to be 6-9%;
2) A heating procedure: the heating temperature of the continuous casting billet is 1150-1200 ℃, and the soaking time is 1-3 h;
3) A rolling procedure: a two-stage controlled rolling process is adopted; wherein the finishing temperature of the first stage is more than or equal to 1050 ℃, and the single-pass reduction rate is 8-11%; the initial rolling temperature of the second stage is more than or equal to 970 ℃, and the single-pass reduction rate is 5-8%;
4) A heat treatment process: the thickness of the finished steel plate is 40-100 mm; selecting different heat treatment processes for the rolled steel plate according to the thickness; wherein t is more than or equal to 40mm and less than or equal to 60mm, and t is the thickness of the steel plate, and the steel plate with t is more than or equal to 60mm and less than or equal to 100mm adopts a normalizing weak cold heat treatment process, and the steel plate with t is more than or equal to 60mm and less than or equal to 100mm adopts a short-time normalizing heat treatment process.
3. The production method of the 800 MPa-grade hydrogen-induced crack resistant container steel plate according to claim 2, characterized in that the smelting process adopts an electric furnace smelting and VOD vacuum treatment smelting process.
4. The production method of the 800MPa grade hydrogen-induced crack resistant container steel plate according to claim 2, characterized in that in the heat treatment process, the normalizing weak cold heat treatment process comprises the following steps: the heat treatment temperature is controlled to be 880-890 ℃, the temperature rising rate is 1.1-1.3.min/mm, the net heat preservation time is 0.5-0.6 min/mm, the steel is discharged from the furnace for weak cooling after reaching the temperature, and the cooling speed is 1.6-2.0 ℃/s; the temperature of the red returning is 330-340 ℃.
5. The production method of the 800MPa grade hydrogen-induced crack resistant container steel plate is characterized in that in the heat treatment process, the short-time normalizing heat treatment process comprises the following steps: the heat treatment temperature is controlled between 860 and 880 ℃, the heating rate is 1.2 to 1.4min/mm, the steel is discharged from the furnace for air cooling after reaching the temperature, and the total furnace time is less than or equal to 2 hours.
6. The production method of the 800MPa grade hydrogen-induced crack resistant container steel plate according to the claim 2, characterized in that the microstructure of the finished steel plate is ferrite + pearlite + a small amount of bainite evenly dispersed.
7. The production method of the 800MPa grade hydrogen-induced crack resistant container steel plate is characterized in that the properties of the finished steel plate are as follows: the yield strength is 444-453 MPa, the tensile strength is 806-828 MPa, and the elongation after fracture is more than or equal to 24 percent; charpy impact work kV at-20 ℃ for 3 samples 2 The average value is more than or equal to 242J, b =2a, and d =3a is qualified in a 180 DEG cold bending test; and (4) performing a hydrogen induced cracking test according to GB/T8650-2006, and evaluating the product to be qualified according to NACE TM0284 'evaluation method for hydrogen induced cracking resistance of pipeline steel and pressure vessel steel'.
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Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2011001607A (en) * | 2009-06-19 | 2011-01-06 | Sumitomo Metal Ind Ltd | Thick steel plate having excellent hydrogen-induced cracking resistance and brittle crack arrest property |
| CN103556047A (en) * | 2013-10-22 | 2014-02-05 | 首钢总公司 | 450MPa-grade hydrogen-induced-cracking-resistant pressure vessel steel plate and production method thereof |
| CN105603313A (en) * | 2016-01-25 | 2016-05-25 | 宝山钢铁股份有限公司 | Steel for petroleum casing pipe with low yield ratio, manufacturing method of steel and production method of casing pipe |
| CN108411196A (en) * | 2018-03-27 | 2018-08-17 | 武汉钢铁有限公司 | Tensile strength is 680MPa grades of large-scale mobile steelss for pressure vessel use and production method |
| CN109694991A (en) * | 2017-10-20 | 2019-04-30 | 鞍钢股份有限公司 | A kind of tank plate that hydrogen induced cracking resistance can be excellent |
-
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Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2011001607A (en) * | 2009-06-19 | 2011-01-06 | Sumitomo Metal Ind Ltd | Thick steel plate having excellent hydrogen-induced cracking resistance and brittle crack arrest property |
| CN103556047A (en) * | 2013-10-22 | 2014-02-05 | 首钢总公司 | 450MPa-grade hydrogen-induced-cracking-resistant pressure vessel steel plate and production method thereof |
| CN105603313A (en) * | 2016-01-25 | 2016-05-25 | 宝山钢铁股份有限公司 | Steel for petroleum casing pipe with low yield ratio, manufacturing method of steel and production method of casing pipe |
| CN109694991A (en) * | 2017-10-20 | 2019-04-30 | 鞍钢股份有限公司 | A kind of tank plate that hydrogen induced cracking resistance can be excellent |
| CN108411196A (en) * | 2018-03-27 | 2018-08-17 | 武汉钢铁有限公司 | Tensile strength is 680MPa grades of large-scale mobile steelss for pressure vessel use and production method |
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