Steel plate for 14Cr1MoR medium-temperature pressure vessel for hydrogen-contacting equipment

Abstract

The invention discloses a steel plate for a 14Cr1MoR medium-temperature pressure vessel for hydrogen equipment. The steel plate comprises the following chemical components in percentage by weight: 0.14-0.16% of C, 0.60-0.70% of Si, 0.48-0.64% of Mn, less than or equal to 0.009% of P, less than or equal to 0.004% of S, 1.30-1.40% of Cr, 0.50-0.60% of Mo, less than or equal to 0.003% of Sb, less than or equal to 0.010% of Sn, less than or equal to 0.010% of As, less than or equal to 150 of J coefficient, less than or equal to 15 of X coefficient and the balance of Fe and inevitable impurities. The steel plate has good conventional performance and also has good low-temperature impact toughness, high-temperature tensile property, Z-direction tensile property, tempering embrittlement resistance and PWHT performance, the process is simple and easy to implement, the performance stability of the steel plate is high, and the steel plate can be widely applied to hydrogen equipment in petrochemical industry and coal chemical industry.

Description

Technical Field

[0001] The present invention belongs to the technical field of manufacturing medium-temperature pressure vessel steel plates, and particularly relates to a 14Cr1MoR medium-temperature pressure vessel steel plate for hydrogen-containing equipment. Background Art

[0002] 14Cr1MoR(H) is a pressure vessel steel used in steel plates and steel strips for pressure-bearing equipment in GB / T 713.2-2023. The standard requires normalizing + tempering for delivery. It is widely used in the petrochemical and coal chemical industries for manufacturing equipment such as hydrogenation reactors, reduction reactors, shift furnaces, gasification furnaces, heat exchangers, towers, hot high-pressure separators, and depressant condensers. The service environment is harsh (high temperature of 400 - 600°C, high pressure, hydrogen corrosion, long-term temper embrittlement). The steel plate is required to have high-temperature strength and plasticity, excellent oxidation resistance and corrosion resistance, good processing performance and welding performance, and good tissue stability.

[0003] Chinese Patent CN 116377342 A discloses "a 15CrMoR(H) steel plate for hydrogen-containing equipment and its manufacturing method". The manufacturing method of the steel plate is: converter steelmaking → continuous casting → heating → rolling → normalizing (allowing accelerated cooling) → tempering → flaw detection → inspection → warehousing. The 15CrMoR(H) steel plate for hydrogen-containing equipment produced by this process has good strength and toughness matching, and the performance difference of the whole steel plate is small, ensuring good processing performance and welding performance of the steel plate; the UT flaw detection of the steel plate meets the requirements of TI level standard in NB / T47013.3-2015.

[0004] The disadvantage is that the production process of normalizing with accelerated cooling has high requirements for equipment and is not applicable to all production enterprises, with poor applicability.

[0005] Chinese Patent CN 109518079 A discloses "a production method of a 15CrMoR steel plate for hydrogen-containing equipment". The production process flow is converter smelting → LF refining → VD vacuum treatment → continuous casting → slab heating → controlled rolling → online cooling → heat treatment. The physical quality and various properties of the products produced by the method of the present invention: the yield surplus at 1 / 2 plate thickness of the head and tail samples of the steel plate after the maximum simulated post-weld heat treatment is 40 - 100 Mpa, and the tensile surplus is 50 - 80 Mpa. The low-temperature impact performance is stable and the surplus is large. The disadvantage is that the production process of online quenching + tempering has very high requirements for equipment and process control accuracy and is not applicable to all production enterprises, with poor applicability.

[0006] Chinese Patent CN 105861941 B discloses "an extra-large thickness steel plate for hydrogen-containing equipment and its preparation method". The first disadvantage is that the steel plate thickness is 200 mm, which is not applicable to all steel plates. The second is that the production process of electric furnace smelting and ingot casting is not applicable to other production enterprises. Summary of the Invention

[0007] The object of the present invention is to provide a steel plate for 14Cr1MoR(H) pressure vessels for hydrogen-containing equipment, which has good conventional properties, and at the same time has good low-temperature impact toughness, high-temperature tensile properties, Z-direction tensile properties, resistance to temper embrittlement and PWHT properties, and the process is simple and easy to implement, and the performance stability of the steel plate is high, and it can be widely used in hydrogen-containing equipment in the petrochemical and coal chemical industries.

[0008] To solve the above technical problems, the present invention adopts the following technical solutions:

[0009] For a steel plate for medium-temperature pressure vessels of 14Cr1MoR for hydrogen-containing equipment of the present invention, the chemical composition of the steel plate by weight percentage is C: 0.14-0.16%, Si: 0.60-0.70%, Mn: 0.48-0.64%, P: ≤0.009%, S: ≤0.004%, Cr: 1.30-1.40%, Mo: 0.50-0.60%, Sb≤0.003%, Sn≤0.010%, As≤0.010%, J coefficient≤150, X coefficient≤15, and the balance is Fe and inevitable impurities;

[0010] The main steps and process parameters of its manufacturing method are as follows:

[0011] S1 Use high-quality hot metal (harmful elements Sb≤0.003%, Sn≤0.010%, As≤0.010%) and high-quality scrap steel after desulfurization pretreatment as raw materials, and smelt in an efficient top-bottom combined blowing converter. When tapping, the carbon content is ≥0.06%, the phosphorus content is ≤0.007%, the tapping temperature is greater than 1560°C, and slagging during tapping is avoided;

[0012] S2 LF furnace external refining is used for heating up and alloy fine-tuning. By optimizing the calcium treatment operation and soft blowing process, non-metallic inclusions in the steel are further floated and removed; the white slag holding time is controlled above 20 minutes; secondary dephosphorization is carried out before tapping to further reduce the phosphorus content to below 0.004%;

[0013] S3 The RH process adopts a cyclic deep degassing process to greatly reduce the contents of hydrogen, oxygen and nitrogen gases on the premise of ensuring the stability of the molten steel temperature, and reduce the adverse effects of harmful gases on the steel quality; ensure that the vacuum treatment time at less than 60 Pa is greater than 20 minutes; the pure degassing time is greater than 15 minutes, and the soft blowing time is greater than 15 minutes, ensuring that the off-position molten steel hydrogen content ≤1.6 ppm, oxygen content ≤30 ppm, and nitrogen content ≤50 ppm;

[0014] During continuous casting, dynamic soft reduction is adopted. The soft reduction positions are in segments 8, 9, and 10, and the total reduction amount is 7.5 mm. Electromagnetic stirring is used during continuous casting. The electromagnetic stirring positions are at the outlet of segment 3 and the inlet of segment 4. The electromagnetic stirring frequency is 5 Hz, and the current is 350 A. The water flow rate on the wide side of the mold is 4500 L / min, and the water flow rate on the narrow side is 370 L / min. The inlet water temperature of the mold is 36 ± 2 °C, and the inlet water temperature of the mold is 38 ± 1 °C. The secondary cooling water temperature is 22 - 25 °C, and the water quality index should meet the process requirements. Protective casting is adopted. The argon gas pressure for sealing the long nozzle is greater than 0.3 MPa, and the flow rate is 130 - 160 L / min. The argon gas pressure for sealing the submerged nozzle in the tundish is greater than 0.2 MPa, and the flow rate is 15 - 20 L / min. The superheat during continuous casting is 20 - 30 °C. When changing the ladle, the tundish liquid level is not less than 30 tons. Constant casting speed is adopted, and the casting speed is stable at 1.0 m / min. The straightening temperature of the billet is controlled at 950 - 1000 °C, and the temperature difference along the width direction of the billet shall not exceed 50 °C. Finally, a continuous casting billet with a thickness of 250 mm is produced. The central segregation of the billet in macrostructure is controlled below class C 3.0. After the billet is taken offline, it is stacked and cooled or pit-cooled for more than 48 hours.

[0015] S5 Heat the steel slab in the heating furnace to fully ensure the heating temperature and soaking time of the steel slab. The heating temperature is controlled at 1210 °C - 1250 °C, and the total time in the furnace is controlled at 240 - 270 min to ensure the full solution of alloying elements and the uniform temperature of the steel slab.

[0016] S6 Two-stage controlled rolling is adopted for rolling, usually referred to as the rough rolling stage and the finish rolling stage. Rough rolling is carried out on a 3800 mm rough rolling mill. The rolling start temperature is above 1170 °C, and the relative reduction rate per pass is controlled at least above 15% for at least two passes. The set torque during the first stage of rolling is 2280 kN·m. During finish rolling, the deformation amount of each pass is strictly controlled. The finish rolling start temperature ≤ 900 °C, and the finish rolling end temperature ≤ 800 °C. The set torque during the second stage of rolling is 2320 kN·m. After the steel plate is rolled, laminar cooling is carried out. The water temperature is 17 - 20 °C, and the final cooling temperature is 650 - 700 °C. The head shielding is 0 - 2.0 m, the tail shielding is 0 - 2.5 m, and the edge shielding is 0 - 2.0 m. The overall temperature difference after the steel plate returns to red is controlled ≤ 50 °C. The steel plate is stacked and slowly cooled for 12 hours and then sampled for inspection.

[0017] S7 The heat treatment is normalizing + tempering. According to the empirical formula and combined with the actual production on site, the normalizing temperature is determined to be 910 °C - 930 °C, and the time is 30 min + t × 1.4 min / mm. The tempering temperature is 660 - 690 °C, and the time is 30 min + t × 2.25 min / mm, where t is the thickness of the steel plate in mm.

[0018] Furthermore, the chemical composition of the steel plate by weight percentage is: C: 0.155%, Si: 0.65%, Mn: 0.59%, P: 0.008%, S: 0.002%, Cr: 1.32%, Mo: 0.50%, Sb: 0.0001%, Sn: 0.0013%, As: 0.0017%, J coefficient 126, X coefficient 13.5, and the balance is Fe and inevitable impurities.

[0019] Furthermore, the chemical composition of the steel plate by weight percentage is: C: 0.160%, Si: 0.68%, Mn: 0.58%, P: 0.007%, S: 0.001%, Cr: 1.35%, Mo: 0.51%, Sb: 0.0001%, Sn: 0.0014%, As: 0.0018%, J coefficient 127, X coefficient 13.6, and the balance is Fe and inevitable impurities.

[0020] Furthermore, the raw material hot metal undergoes deep desulfurization of hot metal, top and bottom blowing in the converter, argon blowing in the ladle, LF external refining, RH vacuum treatment and continuous casting processes to obtain a 250 mm thick slab; the slab heating temperature is 1220 °C, the total time in the furnace is 260 min, the starting rolling temperature in the first stage is 1180 °C, the relative reduction per pass is controlled at least in two passes above 14%, when the thickness of the rolled piece is 80 mm, it is held at 920 °C on the roller table, and then the second stage rolling is carried out, the finishing rolling temperature is 850 °C, and the thickness of the finished steel plate is 20 mm; after rolling, the steel plate enters the accelerated cooling (ACC) device and is cooled to 680 °C at a speed of 5 °C / s, and then cooled on the cooling bed after hot straightening; after shot peening, the steel plate is sent for heat treatment, the normalizing temperature is 910 °C, the time in the furnace is 100 minutes, the tempering temperature is 680 °C, and the time in the furnace is 80 minutes; finally, the said steel plate can be obtained.

[0021] Furthermore, the raw material hot metal undergoes deep desulfurization of hot metal, top and bottom blowing in the converter, argon blowing in the ladle, LF external refining, RH vacuum treatment and continuous casting processes to obtain a 250 mm thick slab; the slab heating temperature is 1221 °C, the total time in the furnace is 260 min, the starting rolling temperature in the first stage of rolling is 1195 °C, the starting rolling temperature in the second stage of rolling is 925 °C, the thickness of the rolled piece is 120 mm, the finishing rolling temperature is 860 °C, and the thickness of the finished steel plate is 40 mm; the cooling rate of the steel plate is 5 °C / s, and the final cooling temperature is 680 °C; it is cooled on the cooling bed after hot straightening; after shot peening, the steel plate is heat treated, the normalizing temperature is 910 °C, the time in the furnace is 120 minutes, the tempering temperature is 680 °C, and the time in the furnace is 165 minutes; finally, the said steel plate can be obtained.

[0022] Furthermore, the raw material hot metal is processed through deep desulfurization of hot metal, top and bottom blowing in the converter, argon blowing in the ladle, LF refining outside the furnace, RH vacuum treatment and continuous casting processes to obtain a 250-mm thick slab; the heating temperature of the slab is 1210 °C, the total time in the furnace is 260 min, the starting rolling temperature in the first stage of rolling is 1186 °C, the starting rolling temperature in the second stage of rolling is 923 °C, the thickness of the rolled piece is 108 mm, the finishing rolling temperature is 830 °C, and the thickness of the finished steel plate is 60 mm; it is cooled on the cooling bed after hot straightening; the steel plate is heat-treated after shot blasting, the normalizing temperature is 910 °C, the time in the furnace is 86 min, the tempering temperature is 670 °C, and the time in the furnace is 150 min; finally, the steel plate can be obtained.

[0023] Furthermore, while having good conventional properties, the steel plate also has good low-temperature impact toughness, high-temperature tensile properties, Z-direction tensile properties, resistance to temper embrittlement, and PWHT properties.

[0024] Compared with the prior art, the beneficial technical effects of the present invention are:

[0025] Through reasonable chemical compositions and processes, the present invention obtains a 14Cr1MoR(H) pressure vessel steel plate for hydrogen-containing equipment, which, while having good conventional properties, also has good low-temperature impact toughness, high-temperature tensile properties, Z-direction tensile properties, resistance to temper embrittlement, and PWHT properties. Moreover, the process is simple and easy to implement, and the performance stability of the steel plate is high, and it can be widely applied to hydrogen-containing equipment in the petrochemical and coal chemical industries. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] The present invention will be further described below in conjunction with the drawings.

[0027] Figure 1 It is a 500-fold metallographic structure diagram at 1 / 4 thickness of the steel plate in the as-delivered state of Example 2 of the present invention.

[0028] Figure 2 It is a 500-fold metallographic structure diagram at 1 / 2 thickness of the steel plate in the as-delivered state of Example 2 of the present invention.

[0029] Figure 3 It is a high-temperature tensile specimen of the steel plate in the as-delivered state of Example 1 of the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0030] The present invention will be described in more detail below with examples. These examples are only descriptions of the best implementation modes of the present invention and do not limit the scope of the present invention in any way.

[0031] Example 1

[0032] The raw material hot metal undergoes deep desulfurization of hot metal, top and bottom blowing in the converter, argon blowing in the ladle, LF secondary refining, RH vacuum treatment and continuous casting processes to obtain a 250 mm thick slab with the chemical composition weight percentages shown in Table 1. The heating temperature of the slab is 1220 °C, the total time in the furnace is 260 min, the starting rolling temperature in the first stage is 1180 °C, the relative reduction per pass is controlled at least in two passes above 14%. When the thickness of the rolled piece is 80 mm, it is kept warm to 920 °C on the roller table, and then the second stage rolling is carried out. The finishing rolling temperature is 850 °C, and the thickness of the finished steel plate is 20 mm. After rolling, the steel plate enters the accelerated cooling (ACC) device and is cooled to 680 °C at a speed of 5 °C / s, and then cooled on the cooling bed after hot straightening. After shot blasting, the steel plate is sent for heat treatment. The normalizing temperature is 910 °C, the time in the furnace is 100 minutes, the tempering temperature is 680 °C, and the time in the furnace is 80 minutes. Finally, the described steel plate can be obtained.

[0033] Example 2

[0034] The implementation method is the same as that of Example 1, where the heating temperature is 1221 °C, the total time in the furnace is 260 min, the starting rolling temperature in the first stage rolling is 1195 °C, the starting rolling temperature in the second stage rolling is 925 °C, the thickness of the rolled piece is 120 mm, the finishing rolling temperature is 860 °C, and the thickness of the finished steel plate is 40 mm. The cooling rate of the steel plate is 5 °C / s, and the final cooling temperature is 680 °C. It is cooled on the cooling bed after hot straightening. After shot blasting, the steel plate is heat treated. The normalizing temperature is 910 °C, the time in the furnace is 120 minutes, the tempering temperature is 680 °C, and the time in the furnace is 165 minutes. Finally, the described steel plate can be obtained.

[0035] Example 3

[0036] The implementation method is the same as that of Example 1, where the heating temperature is 1210 °C, the total time in the furnace is 260 min, the starting rolling temperature in the first stage rolling is 1186 °C, the starting rolling temperature in the second stage rolling is 923 °C, the thickness of the rolled piece is 108 mm, the finishing rolling temperature is 830 °C, and the thickness of the finished steel plate is 60 mm. It is cooled on the cooling bed after hot straightening. After shot blasting, the steel plate is heat treated. The normalizing temperature is 910 °C, the time in the furnace is 86 minutes, the tempering temperature is 670 °C, and the time in the furnace is 150 minutes. Finally, the described steel plate can be obtained.

[0037] Table 1 Chemical compositions (wt%) of Examples 1 - 3 of the present invention

[0038]

[0039] The results of the conventional mechanical properties, high-temperature tensile properties, Z-direction tensile properties, and PWHT properties of the steel plates of Examples 1 - 3 of the present invention are shown in Tables 2 - 5.

[0040] Table 2 Mechanical properties of the steel plates of Examples 1 - 3 of the present invention

[0041]

[0042] Table 3 High-temperature tensile properties of the steel plate in the as-delivered condition and after PWHT in Example 1 of the present invention

[0043]

[0044]

[0045] Table 4 Z-direction tensile properties of the steel plate in Example 3 of the present invention

[0046]

[0047] Table 5 Properties of the steel plate after PWHT in Example 2 of the present invention

[0048]

[0049]

[0050] The above-described embodiments are only descriptions of the preferred modes of the present invention, and do not limit the scope of the present invention. Without departing from the design spirit of the present invention, various deformations and improvements made by those of ordinary skill in the art to the technical solution of the present invention shall fall within the protection scope determined by the claims of the present invention.

Claims

1. A steel plate for medium-temperature pressure vessel made of 14Cr1MoR for hydrogen-containing equipment, characterized in that, The chemical composition of the steel plate by weight percentage is C: 0.14 - 0.16%, Si: 0.60 - 0.70%, Mn: 0.48 - 0.64%, P: ≤0.009%, S: ≤0.004%, Cr: 1.30 - 1.40%, Mo: 0.50 - 0.60%, Sb ≤0.003%, Sn ≤0.010%, As ≤0.010%, J coefficient ≤150, X coefficient ≤15, and the balance is Fe and inevitable impurities; The main steps and process parameters of its manufacturing method are as follows: S1 Use high-quality hot metal (harmful elements Sb ≤0.003%, Sn ≤0.010%, As ≤0.010%) and high-quality scrap steel that have undergone desulfurization pretreatment as raw materials, and smelt in a high-efficiency top-bottom combined blowing converter. When tapping, the carbon content ≥0.06%, the phosphorus content ≤0.007%, the tapping temperature is greater than 1560°C, and slagging during tapping is avoided; S2 LF furnace external refining is used for heating up and alloy fine-tuning. By optimizing the calcium treatment operation and soft blowing process, non-metallic inclusions in the steel are further floated and removed; the white slag holding time is controlled above 20 minutes; secondary dephosphorization is carried out before tapping to further reduce the phosphorus content to below 0.004%; S3 The RH process uses a cyclic deep degassing process to significantly reduce the contents of hydrogen, oxygen, and nitrogen gases on the premise of ensuring the stability of the molten steel temperature, and reduce the adverse effects of harmful gases on the steel quality; ensure that the vacuum treatment time at less than 60 Pa is greater than 20 minutes; the pure degassing time is greater than 15 minutes, and the soft blowing time is greater than 15 minutes, ensuring that the off-position molten steel hydrogen content ≤1.6 ppm, oxygen content ≤30 ppm, and nitrogen content ≤50 ppm; S4 During continuous casting, dynamic soft reduction is adopted, and the soft reduction positions are sections 8, 9, and 10, with a total reduction of 7.5 mm; electromagnetic stirring is used during continuous casting, the electromagnetic stirring positions are at the outlet of section 3 and the inlet of section 4, the electromagnetic stirring frequency is 5 Hz, and the current is 350 A; the water volume on the wide side of the mold is 4500 L / min, the water volume on the narrow side is 370 L / min, the mold inlet water temperature is 36 ± 2°C, the mold inlet water temperature is 38 ± 1°C, the secondary cooling water temperature is 22 - 25°C, and the water quality index should meet the process requirements; protective casting is adopted, the argon pressure for sealing the long nozzle is greater than 0.3 MPa, and the flow rate is 130 - 160 L / min; the argon pressure for sealing the submerged nozzle in the tundish is greater than 0.2 MPa, and the flow rate is 15 - 20 L / min; the continuous casting superheat is 20 - 30°C, and the tundish liquid level during ladle change is not less than 30 tons; a constant casting speed is adopted, and the casting speed is stable at 1.0 m / min; the straightening temperature of the slab is controlled at 950 - 1000°C, and the temperature difference along the width direction of the slab shall not exceed 50°C; finally, a continuous casting slab with a thickness of 250 mm is produced, and the center segregation of the slab in the macrostructure is controlled below class C 3.

0. After the slab is taken offline, it is stacked and cooled or pit-cooled for more than 48 hours; S5 Heat the steel slab in the heating furnace to fully ensure the heating temperature and soaking time of the steel slab; the heating temperature is controlled at 1210°C - 1250°C, and the total time in the furnace is controlled at 240 - 270 min to ensure the full solid solution of alloying elements and the uniform temperature of the steel slab; The S6 rolling process adopts two-stage controlled rolling, generally referred to as the rough rolling stage and the finish rolling stage; the rough rolling is carried out on a 3800mm rough rolling mill, the starting rolling temperature is above 1170°C, and the relative reduction per pass is controlled at least in two passes above 15%; the set torque during the first stage of rolling is 2280 kN·m; during finish rolling, the deformation amount of each pass is strictly controlled, the starting rolling temperature of finish rolling ≤ 900°C, and the finishing rolling temperature ≤ 800°C; the set torque during the second stage of rolling is 2320 kN·m; after the steel plate is rolled, laminar cooling is carried out, the water temperature is 17 - 20°C, and the final cooling temperature is 650 - 700°C; the head shielding is 0 - 2.0m, the tail shielding is 0 - 2.5m, and the edge shielding is 0 - 2.0m, and the overall temperature difference after the steel plate returns to red is controlled ≤ 50°C; the steel plate is stacked and slowly cooled for 12 hours and then sampled for inspection; The S7 heat treatment is normalizing + tempering. According to the empirical formula and combined with the actual production on site, the normalizing temperature is determined to be 910°C - 930°C, the time is 30min + t×1.4min / mm, the tempering temperature is 660 - 690°C, and the time is 30min + t×2.25min / mm, where t is the thickness of the steel plate in mm.

2. The steel plate for medium-temperature pressure vessels of 14Cr1MoR for hydrogen-containing equipment according to claim 1, characterized in that, The chemical composition of the said steel plate by weight percentage is C: 0.155%, Si: 0.65%, Mn: 0.59%, P: 0.008%, S: 0.002%, Cr: 1.32%, Mo: 0.50%, Sb: 0.0001%, Sn: 0.0013%, As: 0.0017%, J coefficient 126, X coefficient 13.5, and the balance is Fe and unavoidable impurities.

3. The steel plate for medium-temperature pressure vessels of 14Cr1MoR for hydrogen-containing equipment according to claim 1, characterized in that, The chemical composition of the said steel plate by weight percentage is C: 0.160%, Si: 0.68%, Mn: 0.58%, P: 0.007%, S: 0.001%, Cr: 1.35%, Mo: 0.51%, Sb: 0.0001%, Sn: 0.0014%, As: 0.0018%, J coefficient 127, X coefficient 13.6, and the balance is Fe and unavoidable impurities.

4. The steel plate for medium-temperature pressure vessels of 14Cr1MoR for hydrogen-containing equipment according to claim 2, characterized in that, The raw material hot metal undergoes deep desulfurization of hot metal, top and bottom blowing in the converter, argon blowing in the ladle, LF secondary refining, RH vacuum treatment and continuous casting process to obtain a 250mm thick slab; the slab heating temperature is 1220°C, the total time in the furnace is 260min, the starting rolling temperature of the first stage is 1180°C, and the relative reduction per pass is controlled at least in two passes above 14%. When the thickness of the rolled piece is 80mm, it is kept at a temperature of 920°C on the roller table, and then the second stage of rolling is carried out, and the finishing rolling temperature is 850°C, and the thickness of the finished steel plate is 20mm; after rolling, the steel plate enters the accelerated cooling (ACC) device and is cooled to 680°C at a speed of 5°C / s, and then cooled on the cooling bed after hot straightening; After shot blasting, the steel plate is sent for heat treatment, the normalizing temperature is 910°C, the time in the furnace is 100 minutes, the tempering temperature is 680°C, and the time in the furnace is 80 minutes; finally, the said steel plate can be obtained.

5. The steel plate for medium-temperature pressure vessels of 14Cr1MoR for hydrogen-containing equipment according to claim 3, characterized in that, The raw hot metal is processed through deep desulfurization of hot metal, top and bottom blowing in the converter, argon blowing in the ladle, LF secondary refining, RH vacuum treatment and continuous casting processes to obtain a 250-mm-thick slab; the slab heating temperature is 1221 °C, the total time in the furnace is 260 min, the rolling start temperature in the first stage of rolling is 1195 °C, the rolling start temperature in the second stage of rolling is 925 °C, the thickness of the rolled piece is 120 mm, the finish rolling temperature is 860 °C, and the thickness of the finished steel plate is 40 mm; the cooling rate of the steel plate is 5 °C / s, and the finish cooling temperature is 680 °C; it is cooled on the cooling bed after hot straightening; After shot blasting, the steel plate is heat-treated. The normalizing temperature is 910 °C, the time in the furnace is 120 minutes, the tempering temperature is 680 °C, and the time in the furnace is 165 minutes; finally, the said steel plate can be obtained.

6. The steel plate for medium-temperature pressure vessels of 14Cr1MoR for hydrogen-containing equipment according to claim 4, characterized in that, The raw hot metal is processed through deep desulfurization of hot metal, top and bottom blowing in the converter, argon blowing in the ladle, LF secondary refining, RH vacuum treatment and continuous casting processes to obtain a 250-mm-thick slab; the slab heating temperature is 1210 °C, the total time in the furnace is 260 min, the rolling start temperature in the first stage of rolling is 1186 °C, the rolling start temperature in the second stage of rolling is 923 °C, the thickness of the rolled piece is 108 mm, the finish rolling temperature is 830 °C, and the thickness of the finished steel plate is 60 mm; it is cooled on the cooling bed after hot straightening; After shot blasting, the steel plate is heat-treated. The normalizing temperature is 910 °C, the time in the furnace is 86 minutes, the tempering temperature is 670 °C, and the time in the furnace is 150 minutes; finally, the said steel plate can be obtained.

7. The steel plate for medium-temperature pressure vessels of 14Cr1MoR for hydrogen-containing equipment according to claim 1, characterized in that, While having good conventional properties, the said steel plate also has good low-temperature impact toughness, high-temperature tensile properties, Z-direction tensile properties, resistance to temper embrittlement and PWHT properties.

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