1100MPa grade steel for pressure-bearing equipment, manufacturing, forming and post-heat treatment methods

Abstract

The present invention provides a 1100MPa grade steel for pressure-bearing equipment, a manufacturing method, a forming method and a subsequent heat treatment method. The steel plate has the following components by weight percentage: C 0.16% to 0.20%, Si 0.15% to 0.35%, Mn 0.60% to 1.00%, P ≤ 0.010%, S ≤ 0.003%, Cr 0.40% to 0.65%, Mo 0.40% to 0.60%, Ni 0.70% to 1.00%, Cu 0.15% to 0.50%, V 0.04% to 0.08%, Ti 0.01% to 0.03%, B 0.0005% to 0.0006%, Alt 0.015% to 0.045%, the balance being Fe and unavoidable inclusions; the manufacturing process includes smelting, continuous casting, heating, rolling, and tempering; after forming and heat treatment, a large amount of (10 to 30) nm-level (Fe, Mn, Cr, Mo) is dispersed and precipitated in the steel. 23 C6, Mo2C, (Ti, Mo)2C, VC, and TiC second phase particles and borides improve the strength and plasticity of the matrix to ensure the use requirements of high-strength pressure-bearing equipment.

Description

Technical Field

[0001] The present invention belongs to the field of metal materials, and in particular relates to steel for 1100MPa-level pressure-bearing equipment, and methods for manufacturing, forming and subsequently heat treating the steel. Background Art

[0002] In the production of clean energy such as hydropower and hydrogen, pressure-bearing equipment, as a crucial location for media transmission, storage, and transportation, plays a vital role in the entire production process chain. For example, the tremendous impact exerted on equipment by the falling water in a hydropower station, and the immense internal pressure exerted by highly concentrated compressed hydrogen, can reach pressures exceeding 60 MPa. The special equipment industry defines this as ultra-high pressure, and the tensile strength of the steel used to manufacture such equipment is 1100 MPa. In recent years, to meet the rapid development of the pressure-bearing equipment manufacturing industry, design institutes have proposed pressure-bearing equipment with high efficiency, high parameter, and high reliability design requirements. Existing steel materials with existing strength levels for pressure-bearing equipment cannot meet these design requirements, and ultra-high strength and toughness materials are needed to support the development of high-end equipment.

[0003] The disclosed invention patent "A steel for nuclear power pressure equipment and its manufacturing method" (publication number CN103160732A) is for pressure equipment steel used in the nuclear power field. The tensile strength of the steel plate is 560-625N / mm2. 2 Within the range, the tensile strength after simulated post-weld heat treatment is reduced to 510-600N / mm 2 , when facing a higher pressure service environment, the product cannot provide the higher strength support equipment requirements, especially there is no technical solution and data provided after molding to support its sufficient strength to meet the high pressure service requirements.

[0004] The disclosed invention patent "A hot-rolled weldable steel plate for pressure-bearing equipment and its production method" (publication number CN110983175A) shows, from the disclosed composition, production method and beneficial effects, that the tensile strength of the steel plate involved in the patent is between 450 and 610 MPa in the supplied state and the simulated post-weld heat treatment state, and its microstructure is composed of relatively low-strength ferrite and pearlite. When faced with a higher-pressure service environment, the product cannot meet the higher strength requirements of the supporting equipment, especially there is no technical solution and data provided after forming to support its sufficient strength to meet the high-pressure service requirements.

[0005] The disclosed invention patent "A non-magnetic stainless steel hot-rolled plate with a tensile strength of 1100MPa and its manufacturing method" (publication number CN108374119A) shows, from the disclosed composition, production method and beneficial effects, that the patented invention product is an austenitic stainless steel plate. Although the tensile strength reaches 1100MPa, the cost is relatively high due to the addition of a large amount of chromium and nickel elements, and there is no relevant post-forming technical solution and data to support that it has sufficient strength to meet high-pressure service requirements.

[0006] The strength of the steel used in the above invention and existing pressure-bearing equipment and the strength after forming can no longer meet the development needs of large-scale, high-parameter pressure-bearing equipment for clean energy such as hydropower and hydrogen energy. Therefore, there is an urgent need to develop 1100MPa-level (10-40)mm thin-gauge high-strength key materials for pressure-bearing equipment with ultra-high strength at room temperature, high strength at high temperature and good plasticity and toughness after forming to support the development needs of new, high-parameter pressure-bearing equipment or equipment in my country's energy field. Summary of the Invention

[0007] The purpose of the present invention is to overcome the problem that the above inventions are insufficient in strength or cannot provide a technical solution to improve the strength of high-strength pressure-bearing equipment after forming, and to provide a steel plate with a thickness specification of (10 to 40) mm and a steel product for pressure-bearing equipment with a tensile strength of 1100 MPa after forming, manufacturing, forming and subsequent heat treatment process to meet the manufacturing needs of high-strength pressure-bearing equipment.

[0008] The object of the invention is achieved like this:

[0009] 1100MPa grade steel for pressure-bearing equipment: the steel plate has the following composition by weight percentage: C 0.16%-0.20%, Si 0.15%-0.35%, Mn 0.60%-1.00%, P≤0.010%, S≤0.003%, Cr 0.40%-0.65%, Mo 0.40%-0.60%, Ni 0.70%-1.00%, Cu 0.15%-0.50%, V 0.04%-0.08%, Ti 0.01%-0.03%, B 0.0005%-0.0006%, Alt 0.015%-0.045%, and the balance is Fe and unavoidable inclusions.

[0010] The thickness of steel plates for pressure-bearing equipment is 10 to 40 mm.

[0011] The mechanical properties of steel plates for pressure equipment are 820MPa≤R p0.2 ≤950MPa、1100MPa≤R m ≤1210MPa, impact energy KV2≥100J at -20℃.

[0012] The reasons for the composition design of the present invention are as follows:

[0013] Carbon is the most important element for increasing steel strength. Its addition significantly improves steel's hardenability. Furthermore, the carbon in this invention combines with strong carbide alloying elements in the steel to produce precipitation strengthening, resulting in a secondary hardening effect, ensuring the steel's high strength requirements. When the carbon content is below 0.13%, hardenability is low, making it difficult to obtain a uniform tempered martensite structure during subsequent tempering, and the steel's strength fails to meet performance requirements. However, excessive carbon content can affect the steel's machinability, so this invention limits the carbon content to 0.16% to 0.20%.

[0014] Silicon acts as a reducing agent and deoxidizer during steelmaking. Silicon has a certain impact on martensitic transformation during tempering. When the silicon content exceeds 0.5%, it hinders the activity of carbon in martensite during tempering, causing the formation of ε carbides instead of M3C carbides in martensitic steel. This reduces the hardness and toughness of the steel and increases the sensitivity to temper brittleness. Therefore, the present invention limits the silicon content to 0.15% to 0.35%.

[0015] Mn is an element that strongly stabilizes austenite, can effectively reduce the decomposition rate of austenite, improve the hardenability of steel, and can strongly increase the strength and hardness of steel. However, a high Mn content will enhance the temper brittleness of steel. Therefore, the present invention limits the Mn content range to 0.60% to 1.00%.

[0016] S and P are harmful elements in steel and must be strictly controlled to ensure the purity and plasticity of the steel. Therefore, the present invention limits the content of S to 0.003% and the content of P to 0.010%.

[0017] Adding a certain amount of Cr to Cr steel significantly improves the steel's hardenability and ensures the steel's matrix strength. Furthermore, Cr is a strong carbide-forming element, forming stable carbides with carbon in the steel, which improves the pressure-bearing capacity of pressure-bearing equipment. When the Cr content is less than 0.3%, the improvement in hardenability is minimal, which is detrimental to the formation of lath martensite and cannot meet the high-strength performance requirements of the steel. Therefore, the present invention limits the Cr content to 0.40% to 0.65%.

[0018] Mo can improve the hardenability of steel, effectively refine austenite grains, and enhance the solid solution strengthening of ferrite. The addition of a certain amount of Mo can improve the steel's tempering resistance and inhibit temper embrittlement. Molybdenum is also a strong carbide-forming element. The Mo2C carbide formed during tempering has a secondary hardening effect, especially when combined with a small amount of Ti to form a stable secondary hardening phase (Mo,Ti)2C. Therefore, the present invention limits the Mo content to 0.40% to 0.60%.

[0019] Nickel is an alloying element that expands the austenite region and refines the ferrite grains, ensuring strength without compromising the steel's plasticity and toughness, especially its low-temperature toughness. However, since nickel is a precious metal, the present invention limits the nickel content to 0.70% to 1.00% for cost-effectiveness.

[0020] Cu improves the strength of steel through solid solution strengthening and also has the effect of improving hardenability. Therefore, the present invention limits the Cu content to 0.15% to 0.50%.

[0021] Adding an appropriate amount of V can form highly stable fine carbides (VC) with C. These are dispersed within the grains and at the grain boundaries, significantly hindering the slip and climb of dislocations, thereby enhancing the matrix strength and hardness of the steel. However, excessive V content will increase the yield strength ratio of the steel, which is not conducive to forming and manufacturing. Therefore, the present invention limits the V content to 0.04% to 0.08%.

[0022] Ti has a solid solution strengthening effect, dissolving in austenite to improve the steel's hardenability and tempering stability after quenching. During tempering, stable second-phase (Ti, Mo)2C particles precipitate, which have a strong secondary hardening effect, increasing the steel's strength and thermal resistance, as well as improving its weldability. Therefore, the present invention limits the Ti content to 0.01% to 0.03%.

[0023] B increases the hardenability of steel and at the same time utilizes the high-hardness boride formed by boron to improve the strength of steel. However, a boron content exceeding 0.007% will cause hot brittleness of the steel and affect the forming and processing performance of pressure-bearing equipment. The present invention limits the B content range to 0.0005% to 0.0006%.

[0024] Alt is a commonly used deoxidizer in steel. Adding a small amount of aluminum can refine the grain size and improve the steel's strength and impact toughness. Excessive amounts can affect the steel's hot working, welding, and machinability. The present invention limits the Alt content to 0.015% to 0.045%.

[0025] The second technical solution of the present invention is to provide a method for manufacturing 1100MPa grade steel for pressure-bearing equipment, including smelting, continuous casting, heating, rolling, and tempering;

[0026] Smelting: including molten iron pretreatment - converter dephosphorization - converter decarburization - refining outside the furnace - vacuum degassing - slab continuous casting - stacking slow cooling - ingot cleaning - heating - rolling - hot straightening - slow cooling - heat treatment - flaw detection - inspection and testing.

[0027] Molten steel is smelted in a converter, using high-quality scrap steel and molten iron as raw materials. The molten iron content is controlled at 75% to 85%. At the same time, in order to effectively reduce the content of harmful elements P, dephosphorization and decarburization are carried out separately in a converter. The dephosphorization oxygen blowing is controlled at 7 to 10 minutes, and the decarburization oxygen blowing is controlled at 8 to 12 minutes, ultimately reducing the phosphorus mass fraction to within 0.006%; deep desulfurization treatment is carried out in the LF refining furnace, and the sulfur content is controlled below 0.002%; degassing is completed in the VD furnace, with a net cycle time of 10 to 15 minutes and a calming time of 3 to 5 minutes before pouring.

[0028] Continuous Casting: After breaking vacuum, casting is performed using a slab continuous casting machine. The superheat is set at 20-30°C, and the casting rate during casting is 1.0-1.4 m / min. The slabs are stacked and slowly cooled after leaving the production line for 24-36 hours. The stacks are then unstacked at temperatures below 400°C to prevent cracks and other defects caused by rapid cooling.

[0029] Heating: The heating temperature is controlled at 1180-1230°C, and the total heating time is 4.0-6.0 hours.

[0030] Rolling: Rolling is carried out using a two-stage controlled rolling method. The final rolling temperature in the recrystallization zone is ≥1000°C. To fully fragment the core structure of the billet, a total deformation rate of ≥50% is required. The rolling temperature in the non-recrystallization zone begins at 830-870°C, and the final rolling temperature is 810-850°C, with a total deformation rate of ≥60%. During this process, the austenite grains are further flattened and elongated. As the grain boundary area increases, the ferrite nucleation rate increases during the subsequent phase transformation, and the grains are fully refined. The target thickness of the rolled product is (10-40) mm.

[0031] Tempering: Due to the addition of a large amount of solid solution strengthening elements such as C, Mn, Cr, Mo, and Ni to the steel, the steel plate can obtain a lath martensite structure with ultra-high strength and hardness after rolling. However, the steel plate has a coarse grain size, and there is structural stress and thermal stress concentration, which is prone to delayed cracking during flame cutting. Therefore, timely heat treatment should be used to soften and relieve stress. The present invention uses tempering heat treatment to ensure that the strength of the pressure-bearing steel plate is not lost while giving the steel plate appropriate plastic toughness, which is beneficial for the steel plate's forming process. Therefore, the tempering heat treatment temperature of the steel is 650-700°C, and the net holding time is 2.0-4.0 min / mm.

[0032] The third technical solution of the present invention is to provide a forming method and a post-heat treatment method for 1100MPa grade pressure-bearing equipment steel.

[0033] Steel Plate Forming Heat Treatment Process: Hot forming is an essential process for steel plate manufacturing of pressure-bearing equipment. The forming process not only enables the equipment to obtain the required shape, but also is an important means to improve the ultimate strength of pressure-bearing equipment.

[0034] The present invention develops an optimal forming heat treatment process for steel. The parameters and reasons are as follows: the forming process is to maintain heat at 900-930°C for 1.0-2.0 min / min, and then enter a salt water bath after being removed from the furnace and rapidly cool to room temperature at a cooling rate of 20-35°C / s. During this process, chemical elements C, Mn, Cr, Mo, Ni, and microalloying elements such as V, Ti, and B enter the austenite region. After a period of holding heat, the alloying elements are dissolved in the austenite matrix. Subsequently, the steel is placed in a salt water bath at 0-10°C and rapidly cooled at a cooling rate of 20-35°C / s to obtain a fine lath martensite structure. At this time, the steel has ultra-high strength, meeting the requirements of pressure-bearing equipment; however, the plasticity and toughness of the steel are poor and the structural stress is high. A short tempering heat treatment with a heating temperature of 600-630°C and a net holding time of 1.0-1.5h promptly eliminates quenching stress, softens the structure, improves the plasticity and toughness of the steel, and completes the steel forming process. At this time, the steel microstructure is tempered martensite.

[0035] However, if the ultra-high strength and excellent plasticity and toughness of steel for pressure-bearing equipment are to be guaranteed, the size and type of the second phase particles in the steel must be further adjusted, i.e., secondary hardening heat treatment is performed at 630-660°C for 2.0-4.0 hours. At this time, a large amount of (10-30) nm-level (Fe, Mn, Cr, Mo) particles are dispersed and precipitated in the steel. 23 C6, Mo2C, (Ti, Mo)2C, VC, and TiC second phase particles and borides account for 15% to 20% by volume. The second phase particles interact with the high density dislocations in the martensite to improve the strength and plasticity of the matrix and ensure the use requirements of high-strength pressure-bearing equipment. The mechanical properties of the steel after forming and heat treatment are 850MPa≤R at room temperature. p0.2 ≤980MPa、1100MPa≤R m ≤1230MPa; at 400℃, 520MPa≤R p0.2 ≤580MPa; impact energy KV2 ≥120J at -20℃.

[0036] The beneficial effects of the present invention are:

[0037] (1) By adding Cr, Mo, Ni, Cu, V, Ti, and B alloying elements to the strengthening elements C, Si, and Mn, while strictly controlling the content of harmful elements P and S, and combining the manufacturing process, the steel plate of the present invention obtains a high-density tempered martensite structure.

[0038] (2) The mechanical properties of the steel plate for pressure equipment obtained through a unique production process are 820MPa≤R at room temperature. p0.2 ≤950MPa、1100MPa≤R m ≤1210MPa, elongation A≥21%; impact energy KV2≥100J at -20℃.

[0039] (3) The steel plate of the present invention obtains a high-density tempered martensite complex structure after forming and secondary hardening heat treatment, and a large amount of (10-30) nm-level (Fe, Mn, Cr, Mo) is dispersed and precipitated in the steel. 23 Stable second phase particles such as C6, (Ti, Mo)2C, VC and TiC account for 15% to 20% of the structure, ensuring that the steel plate still has 1100MPa level strength and good plasticity and toughness after forming.

[0040] (4) The mechanical properties of the steel for pressure-bearing equipment of the present invention after forming heat treatment are 850MPa≤R p0.2 ≤980MPa、1100MPa≤R m ≤1230MPa, elongation A≥21%; at 400℃, 520MPa≤R p0.2 ≤580MPa; impact energy KV2 ≥120J at -20℃.

[0041] (5) The present invention obtains a 1100MPa grade high-strength steel plate for pressure-bearing equipment with a thickness specification of (10 to 40) mm. DETAILED DESCRIPTION

[0042] The present invention will be further described below by way of examples.

[0043] The embodiment of the present invention performs smelting, continuous casting, heating, rolling, tempering, forming and heat treatment according to the component ratio of the technical solution.

[0044] A method for manufacturing a 1100MPa grade steel plate for pressure-bearing equipment:

[0045] Heating: The heating temperature is controlled at 1180-1230°C, and the total heating time is 4.0-6.0 hours;

[0046] Rolling: The rolling adopts a two-stage controlled rolling method. The end rolling temperature of the recrystallization zone is ≥1000℃, and the total deformation rate is ≥50%. The starting rolling temperature of the non-recrystallization zone is 830-870℃, the final rolling temperature is 810-850℃, and the total deformation rate is ≥60%.

[0047] Tempering: The tempering temperature is 650-700℃, and the insulation time is 2.0-4.0min / mm.

[0048] Further; smelting: molten steel smelting is carried out in a converter, using high-quality scrap steel and molten iron as raw materials, the molten iron content is controlled at 75% to 85%, dephosphorization and decarburization are smelted separately in a converter, wherein the dephosphorization oxygen blowing is controlled at 7 to 10 minutes, and the decarburization oxygen blowing is controlled at 8 to 12 minutes, and the phosphorus mass fraction is finally reduced to within 0.006%; deep desulfurization treatment is carried out in an LF refining furnace, and the sulfur content is controlled below 0.002%; degassing is completed in a VD furnace, with a net circulation time of 10 to 15 minutes and a calming time of 3 to 5 minutes before pouring.

[0049] Further; continuous casting: superheat is 20-30℃, and the casting rate during casting is 1.0-1.4m / min; the billets are stacked and slowly cooled after coming off the line, and the stacking slow cooling time is 24-36h, and the billets are unstacking below 400℃.

[0050] A forming process for 1100MPa grade steel plates for pressure-bearing equipment.

[0051] Steel plate forming: During the forming process, the steel is heated to 900-930°C for a holding time of 1.0-2.0 min / mm. After exiting the furnace, it is rapidly cooled to room temperature in a salt water bath at 0-10°C at a cooling rate of 20-35°C / s to obtain a fine lath martensite structure. Tempering is then performed at a temperature of 500-530°C for a holding time of 0.5-1.0 h. Furthermore, the microstructure of the steel after forming is tempered martensite.

[0052] A heat treatment process for 1100MPa grade steel plates for pressure-bearing equipment after forming, wherein the heat treatment process is a secondary hardening heat treatment, and the process comprises: heating temperature of 630-660°C and heat preservation of 2.0-4.0h.

[0053] Further; (10 to 30) nm level (Fe, Mn, Cr, Mo) precipitated in the microstructure of the steel after secondary hardening heat treatment 23 The volume percentage of C6, Mo2C, (Ti, Mo)2C, VC, and TiC second phase particles and borides is 15% to 20% of the tissue.

[0054] The composition of the steel of the present invention is shown in Table 1. The main process parameters of the steel of the present invention are shown in Table 2. The mechanical properties and microstructure of the steel of the present invention are shown in Table 3. The mechanical properties and microstructure of the steel of the present invention after forming and heat treatment are shown in Table 4.

[0055] Table 1 Composition of steel according to the present invention (wt%)

[0056]

[0057] Table 2 Main process parameters of steel according to the present invention

[0058]

[0059]

[0060] Table 3 Mechanical properties and microstructure of steel according to the present invention

[0061] Example Sampling location <![CDATA[R p0.2 / MPa]]> <![CDATA[R m / MPa]]> A / ％ <![CDATA[(-20℃)KV2 / J]]> Microstructure 1 T / 4 820 1106 24.0 155 Tempered martensite 2 T / 4 846 1180 24.0 145 Tempered martensite 3 T / 4 873 1203 22.5 141 Tempered martensite 4 T / 4 950 1230 23.0 152 Tempered martensite 5 T / 4 937 1196 22.5 140 Tempered martensite 6 T / 4 920 1206 23.0 149 Tempered martensite 7 T / 4 878 1167 23.0 176 Tempered martensite 8 T / 4 951 1130 21.0 130 Tempered martensite 9 T / 4 833 1115 22.5 147 Tempered martensite 10 T / 4 912 1179 22.0 142 Tempered martensite

[0062] Table 4 Mechanical properties and microstructure of steel formed and heat treated in the present invention

[0063]

[0064] According to the above results, the 1100MPa grade steel plate for pressure-bearing equipment produced by the present invention has extremely low P and S harmful element contents, and its mechanical properties are 820MPa≤R p0.2 ≤950MPa、1100MPa≤R m ≤1210MPa, elongation A≥21%; impact energy KV2≥100J at -20℃. After forming and heat treatment, the mechanical properties of the steel are 850MPa≤R p0.2 ≤980MPa、1100MPa≤R m ≤1230MPa, elongation A≥21%; at 400℃, steel pipe 520MPa≤R p0.2 ≤580MPa; impact energy KV2 ≥120J at -20℃.

[0065] In order to describe the present invention, the present invention has been appropriately and fully illustrated through the examples above. The above embodiments are only used to illustrate the present invention, and are not intended to limit the present invention. Ordinary technicians in the relevant technical field can make various changes and modifications without departing from the spirit and scope of the present invention. Any modifications, equivalent substitutions, improvements, etc. made should be included in the scope of protection of the present invention, and the patent protection scope of the present invention should be defined by the claims.

Claims

1. A 1100MPa grade steel plate for pressure-bearing equipment, characterized in that: The steel plate has the following composition by weight percentage: C 0.16% to 0.20%, Si 0.24% to 0.35%, Mn 0.60% to 1.00%, P ≤ 0.010%, S ≤ 0.003%, Cr 0.40% to 0.58%, Mo 0.40% to 0.60%, Ni 0.70% to 1.00%, Cu 0.15% to 0.50%, V 0.04% to 0.08%, Ti 0.02% to 0.03%, B 0.0005% to 0.0006%, Alt 0.015% to 0.028%, and the balance is Fe and unavoidable inclusions; The manufacturing method of the 1100MPa grade steel plate for pressure-bearing equipment includes smelting, continuous casting, heating, rolling, and tempering; Heating: The heating temperature is controlled at 1180~1230℃, and the total heating time is 4.0~6.0h; Rolling: The rolling adopts a two-stage controlled rolling method. The end rolling temperature of the recrystallization zone is ≥1000℃, and the total deformation rate is ≥50%; the starting rolling temperature of the non-recrystallization zone is 830~870℃, the final rolling temperature is 810~850℃, and the total deformation rate is ≥60%; Tempering: The tempering temperature is 650~700℃, and the net holding time is 2.0~4.0 min / mm.

2. The 1100MPa grade steel plate for pressure-bearing equipment according to claim 1, characterized in that: The thickness of steel plates for pressure-bearing equipment is 10~40mm.

3. The 1100MPa grade steel plate for pressure-bearing equipment according to claim 1, characterized in that: The mechanical properties of steel plates for pressure equipment are 820MPa≤ R p0.2 ≤950MPa、1100MPa≤ R m ≤1210MPa, impact energy at -20℃ KV 2≥100J.

4. The 1100 MPa grade steel plate for pressure-bearing equipment according to claim 1, characterized in that: Smelting: Molten steel is smelted in a converter using high-quality scrap steel and molten iron as raw materials. The molten iron content is controlled at 75%~85%. Dephosphorization and decarburization are carried out separately in a converter. The oxygen blowing period for dephosphorization is controlled at 7~10 minutes, and the oxygen blowing period for decarburization is controlled at 8~12 minutes, ultimately reducing the phosphorus mass fraction to less than 0.006%. Deep desulfurization is carried out in the LF refining furnace, and the sulfur content is controlled below 0.002%. Degassing is completed in the VD furnace, with a net circulation time of 10~15 minutes and a calming time of 3~5 minutes before pouring.

5. The 1100 MPa grade steel plate for pressure-bearing equipment according to claim 1, characterized in that: Continuous casting: The superheat is 20~30℃, and the casting rate during casting is 1.0~1.4m / min; the billets are stacked and slowly cooled after leaving the production line, and the stacking slow cooling time is 24~36h. They are unstacking below 400℃.

6. A forming process for the 1100 MPa grade steel plate for pressure-bearing equipment according to any one of claims 1 to 5, characterized in that: Steel plate forming: During the forming process, the heating temperature is 900~930℃ and the net holding time is 1.0~2.0min / mm. After leaving the furnace, it is quickly cooled to room temperature in a salt water bath at a cooling rate of 20~35℃ / s to obtain a fine lath martensite structure; then tempering is carried out at a tempering temperature of 600~630℃ and the net holding time is 1.0~1.5h; The microstructure of the steel after plate forming is tempered martensite.

7. The post-forming heat treatment process for 1100 MPa grade steel plate for pressure-bearing equipment according to claim 6, characterized in that: The heat treatment process is a secondary hardening heat treatment, which has the following process: heating temperature 630~660℃, net holding time 2.0~4.0h; after the secondary hardening heat treatment, 10~30nm level (Fe, Mn, Cr, Mo) are precipitated in the microstructure of the steel. 23 The volume percentage of C6, Mo2C, (Ti, Mo)2C, VC, and TiC second phase particles and borides is 15%~20% of the tissue.

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