CN114672631A - Method for regulating and controlling full-thickness structure-stress-performance uniformity of ultra-thick forging of large hydrogenation reactor - Google Patents
Method for regulating and controlling full-thickness structure-stress-performance uniformity of ultra-thick forging of large hydrogenation reactor Download PDFInfo
- Publication number
- CN114672631A CN114672631A CN202210305337.8A CN202210305337A CN114672631A CN 114672631 A CN114672631 A CN 114672631A CN 202210305337 A CN202210305337 A CN 202210305337A CN 114672631 A CN114672631 A CN 114672631A
- Authority
- CN
- China
- Prior art keywords
- temperature
- heating
- cooling
- forging
- delta
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
- 238000005242 forging Methods 0.000 title claims abstract description 94
- 238000000034 method Methods 0.000 title claims abstract description 53
- 238000005984 hydrogenation reaction Methods 0.000 title claims abstract description 28
- 230000001105 regulatory effect Effects 0.000 title claims abstract description 14
- 230000001276 controlling effect Effects 0.000 title claims abstract description 13
- 238000010438 heat treatment Methods 0.000 claims abstract description 138
- 238000001816 cooling Methods 0.000 claims abstract description 109
- 230000008569 process Effects 0.000 claims abstract description 27
- 238000010791 quenching Methods 0.000 claims abstract description 26
- 230000000171 quenching effect Effects 0.000 claims abstract description 26
- 238000003754 machining Methods 0.000 claims abstract description 15
- 229910000831 Steel Inorganic materials 0.000 claims description 24
- 239000010959 steel Substances 0.000 claims description 24
- 230000009467 reduction Effects 0.000 claims description 8
- 229910001563 bainite Inorganic materials 0.000 claims description 3
- 230000001360 synchronised effect Effects 0.000 abstract description 7
- 238000007599 discharging Methods 0.000 abstract description 6
- 230000035882 stress Effects 0.000 description 26
- 238000004321 preservation Methods 0.000 description 14
- 230000000052 comparative effect Effects 0.000 description 13
- 238000012360 testing method Methods 0.000 description 9
- 238000011084 recovery Methods 0.000 description 6
- 239000013078 crystal Substances 0.000 description 5
- 230000000694 effects Effects 0.000 description 5
- 230000000630 rising effect Effects 0.000 description 5
- 238000009413 insulation Methods 0.000 description 3
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 3
- 230000006378 damage Effects 0.000 description 2
- 230000006872 improvement Effects 0.000 description 2
- 238000002347 injection Methods 0.000 description 2
- 239000007924 injection Substances 0.000 description 2
- 238000004519 manufacturing process Methods 0.000 description 2
- 238000001953 recrystallisation Methods 0.000 description 2
- 238000007670 refining Methods 0.000 description 2
- 238000005496 tempering Methods 0.000 description 2
- 230000008646 thermal stress Effects 0.000 description 2
- HMUNWXXNJPVALC-UHFFFAOYSA-N 1-[4-[2-(2,3-dihydro-1H-inden-2-ylamino)pyrimidin-5-yl]piperazin-1-yl]-2-(2,4,6,7-tetrahydrotriazolo[4,5-c]pyridin-5-yl)ethanone Chemical compound C1C(CC2=CC=CC=C12)NC1=NC=C(C=N1)N1CCN(CC1)C(CN1CC2=C(CC1)NN=N2)=O HMUNWXXNJPVALC-UHFFFAOYSA-N 0.000 description 1
- RWSOTUBLDIXVET-UHFFFAOYSA-N Dihydrogen sulfide Chemical compound S RWSOTUBLDIXVET-UHFFFAOYSA-N 0.000 description 1
- VGGSQFUCUMXWEO-UHFFFAOYSA-N Ethene Chemical compound C=C VGGSQFUCUMXWEO-UHFFFAOYSA-N 0.000 description 1
- 239000005977 Ethylene Substances 0.000 description 1
- 238000007792 addition Methods 0.000 description 1
- 230000004075 alteration Effects 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 238000006356 dehydrogenation reaction Methods 0.000 description 1
- 238000011161 development Methods 0.000 description 1
- 239000007789 gas Substances 0.000 description 1
- 238000002309 gasification Methods 0.000 description 1
- 229910000037 hydrogen sulfide Inorganic materials 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000000465 moulding Methods 0.000 description 1
- 238000011056 performance test Methods 0.000 description 1
- 238000002360 preparation method Methods 0.000 description 1
- 238000012545 processing Methods 0.000 description 1
- 238000011946 reduction process Methods 0.000 description 1
- 238000005070 sampling Methods 0.000 description 1
- 238000010583 slow cooling Methods 0.000 description 1
- 238000005728 strengthening Methods 0.000 description 1
- 238000006467 substitution reaction Methods 0.000 description 1
- 230000000451 tissue damage Effects 0.000 description 1
- 231100000827 tissue damage Toxicity 0.000 description 1
- 238000003466 welding Methods 0.000 description 1
Images
Classifications
-
- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
- C21D8/00—Modifying the physical properties by deformation combined with, or followed by, heat treatment
- C21D8/005—Modifying the physical properties by deformation combined with, or followed by, heat treatment of ferrous alloys
-
- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
- C21D1/00—General methods or devices for heat treatment, e.g. annealing, hardening, quenching or tempering
- C21D1/18—Hardening; Quenching with or without subsequent tempering
-
- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
- C21D1/00—General methods or devices for heat treatment, e.g. annealing, hardening, quenching or tempering
- C21D1/26—Methods of annealing
- C21D1/30—Stress-relieving
-
- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
- C21D3/00—Diffusion processes for extraction of non-metals; Furnaces therefor
- C21D3/02—Extraction of non-metals
- C21D3/06—Extraction of hydrogen
-
- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
- C21D2211/00—Microstructure comprising significant phases
- C21D2211/002—Bainite
Landscapes
- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Physics & Mathematics (AREA)
- Thermal Sciences (AREA)
- Crystallography & Structural Chemistry (AREA)
- Mechanical Engineering (AREA)
- Materials Engineering (AREA)
- Metallurgy (AREA)
- Organic Chemistry (AREA)
- Health & Medical Sciences (AREA)
- Child & Adolescent Psychology (AREA)
- Forging (AREA)
Abstract
The invention discloses a method for regulating and controlling the full-thickness structure-stress-performance uniformity of an ultra-thick forging of a large hydrogenation reactor, which mainly comprises the following steps: after forging, cooling the forging to 700 +/-10 ℃ at a cooling speed of 20-30 ℃/h, and preserving heat for 15-20 h; heating to 1040-1080 ℃ in a gradual heating mode, and keeping for a certain time; cooling to 660-720 ℃ in a gradual cooling mode, keeping for a certain time, then cooling to 350-400 ℃, and naturally cooling to room temperature for rough machining; after rough machining is finished, heating to 920-950 ℃, keeping for a certain time, then quickly quenching, and cooling to 200-250 ℃ after quenching; transferring the quenched product to a heat treatment furnace, heating to 660-720 ℃ in a gradual heating mode, and keeping for a certain time; then cooling to below 300 ℃ at a cooling speed of 20-30 ℃/h, and then discharging and air cooling; according to the invention, the post-forging heat treatment process and the heat treatment process are combined, so that the limitation that the core structure and the stress cannot be regulated and controlled in the traditional process is broken, and the synchronous regulation and control of the structure, the performance and the stress in the full thickness direction are realized.
Description
Technical Field
The invention relates to the technical field of hydrogenation reactor preparation, in particular to a full-thickness structure-stress-performance uniformity regulation and control method for an ultra-thick forging of a large hydrogenation reactor.
Background
The hydrogenation reactor is the core equipment of a petrochemical hydrogenation device, is the most important container in petrochemical production, has harsh working conditions, and can work in a high-temperature and high-pressure environment, and the contact medium is corrosive media such as oil gas, hydrogen sulfide and the like, so that the requirement on service safety of the hydrogenation reactor is extremely high. With the development of million tons of oil refining and million tons of ethylene, the hydrogenation reactor develops towards the direction of super-wall thickness and super-diameter, so that the wall thickness of the hydrogenation reactor is over-thick, plate welding cannot be carried out, only hot forging manufacture can be adopted (the recrystallization temperature is higher, and the cold deformation strengthening and recrystallization processes exist at the same time), the structure damage is serious in the hot forging process, the crystal grains are thick, meanwhile, the forging plastic deformation of the super-thick cylinder is severe, large thermal stress is generated, the super-thick cylinder is easy to crack in subsequent use, and the forge piece needs to be subjected to heat treatment to improve the structure and the performance of the forge piece. At present, the heat treatment method commonly used in engineering includes a plurality of heat treatment processes such as normalizing, tempering, rough machining and then normalizing, tempering and the like, for example, the heat treatment process disclosed in chinese patent CN 105385814A. However, the prior heat treatment method is difficult to realize the synchronous recovery of the full-wall thickness structure performance, and the residual stress is large, so that the uniformity of the performance along the wall thickness direction is poor. Therefore, the tissue-stress-performance synchronous regulation and control of the full thickness of the ultra-thick forging of the large hydrogenation reactor are needed to ensure the intrinsic safety of the hydrogenation reactor. In order to solve the problems, the invention provides a full-thickness structure-stress-performance regulation and control method for an ultra-thick forging of a large hydrogenation reactor, which breaks through the limitation that the core structure and stress cannot be regulated and controlled in the traditional process, and realizes synchronous regulation and control of the structure, the performance and the stress in the full-thickness direction.
Disclosure of Invention
The invention aims to provide a full-thickness structure-stress-performance uniformity regulation and control method for an ultra-thick forging of a large hydrogenation reactor, which breaks through the limitation that the core structure and stress cannot be regulated and controlled by the traditional process, and realizes synchronous regulation and control of the structure, the performance and the stress in the full-thickness direction.
In order to achieve the purpose, the invention adopts the technical scheme that:
the invention provides a full-thickness structure-stress-performance uniformity regulation and control method for an ultra-thick forging of a large hydrogenation reactor, which comprises the following steps:
(1) rapidly heating the steel ingot to 300-350 ℃, then heating to 650-700 ℃ at a heating rate not more than 56 ℃/h, and preserving heat for 4-6 h; then, heating the steel ingot to 1180 +/-10 ℃ in sections, and preserving heat for 2-4 hours;
the steps aim to ensure the temperature uniformity in the forging process, reduce the crystal grain damage and reduce the structure-stress-performance unevenness caused by the temperature unevenness;
(2) forging and forming the steel ingot within the steel ingot forging temperature range in the step (1), and controlling the forging final temperature to be not less than 850 ℃;
(3) after the forging in the step (2) is completed, transferring the forged piece into a heat treatment furnace for slow cooling, wherein the furnace entering temperature of the forged piece is above 850 ℃, then cooling to 700 +/-10 ℃ at a cooling speed of 20-30 ℃/h, and preserving heat for 15-20 h;
in the step (3), the cooling speed is controlled to be 20-30 ℃/h, so that the thermal stress generated in the cooling process can be reduced; and then, heat preservation treatment is carried out at about 700 ℃, so that the structure of the forged piece can be improved, crystal grains can be refined, the grain size can reach 6 grades or above, meanwhile, the residual stress in the forging forming process is partially eliminated, the hardness is reduced, and the residual stress can be reduced to 200-260 MPa.
(4) On the basis of the step (3), heating to 1040-1080 ℃ in a gradual heating manner, and keeping for a certain time t1；
The step (4) is used for further refining the crystal grains of the forge piece;
(5) cooling to 660-720 ℃ in a gradual cooling way and keeping for a certain time t2(ii) a Then gradually cooling to 350-400 ℃, and then naturally cooling to room temperature for rough machining;
the step (5) has the effects of realizing the dehydrogenation treatment of the forge piece, reducing the residual stress and recovering the toughness and the plasticity of the forge piece;
(6) after rough machining is finished, quickly heating to 400 ℃, then heating to 920-950 ℃ in a gradual heating mode, and keeping for a certain time t3(ii) a Then transferring the forged piece to a quenching bath, quenching the forged piece at a cooling speed of not less than 5 ℃/h, and cooling to 200-250 ℃ after quenching;
the steps are quenching treatment, in order to ensure the quenching cooling speed, the water circulation amount of a quenching tank needs to be increased, the forge piece is placed in the quenching tank with a rotary platform at the bottom, the forge piece is rotated by a propeller, the rapid cooling of the forge piece is realized by adopting a rotary water injection mode, a surface gasification film of the forge piece in the quenching process can be broken by adopting the rotary water injection mode, the cooling speed of the forge piece is ensured to reach more than 5 ℃/min, the forge piece is finally ensured to form a lower bainite tissue along the full thickness direction, and the forge piece tissue is improved;
(7) transferring the quenched forge piece to a heat treatment furnace, slowly cooling to 150 +/-10 ℃, and keeping for 3-6 hours; then gradually heating to 660-720 ℃, and keeping for a certain time t4(ii) a Finally, cooling to below 300 ℃ at a cooling speed of 20-30 ℃/h, and discharging and air cooling;
the step (7) is used for further eliminating the residual stress of the forging, reducing the residual stress to be below 100MPa and recovering the toughness and the plasticity of the forging;
in the above stepsIn steps (4) to (7), the t1＝(0.01δ+4)h，t2＝(0.04δ+2)h，t3＝(0.02δ+3)h，t4δ is the forging wall thickness in mm (0.02 δ +10) h.
Further, the segmented temperature rising mode in the step (1) is as follows: heating the steel ingot to 800 +/-20 ℃ at a heating rate of less than 45 ℃/h, and preserving heat for 1-2 h; after the temperature is stable, heating the steel ingot to 900 +/-20 ℃ at the same heating rate, and preserving the heat for 1-2 hours; then, heating to 1000 +/-20 ℃ at the same heating rate, and preserving heat for 1-2 h; and finally, heating to 1180 +/-10 ℃ at the same heating speed, and preserving heat for 2-4 hours.
According to the technical scheme, the temperature of the steel ingot is gradually increased before forging, so that the temperature difference between the core part and the surface of the steel ingot can be reduced, and the uniformity of the structure, the stress and the performance of a forging piece in the full thickness direction can be guaranteed in the forging process.
Further, in the step (2), the temperature of the forged piece is controlled to be not less than 850 ℃ in the forging process, if the temperature is lower than 850 ℃, the forged piece needs to be returned to the furnace to be heated to 1180 +/-10 ℃, and heat is preserved for 1-2 hours.
In the technical scheme, the temperature of the forge piece is controlled to be not less than 850 ℃, so that the forging forming is facilitated, and the tissue damage in the hot forging process is reduced; when the temperature is lower than 850 ℃, the furnace needs to be returned to 1180 +/-10 ℃, the temperature is kept for 1-2 hours, the residual stress generated by deformation and forging in the forging process can be reduced, and then the forging process is repeated.
Further, the gradual temperature rise manner in the steps (4), (6), and (7) is: gradually heating the forging piece at a heating rate of not more than 35 ℃/h for n times to raise the temperature to a planned heating target temperature, wherein the temperature is raised by delta T each timeiKeeping the temperature at a certain value for a certain time t after each temperature risei；
Wherein, Δ TiDetermining according to the wall thickness delta of the forged piece: when delta<At 200mm,. DELTA.Ti130 ℃ under normal temperature; when delta is more than or equal to 200mm and less than 300mm, delta TiThe temperature is 100 ℃; when delta is more than or equal to 300mm and less than 400mm, delta Ti＝80℃；
The calculation mode of the gradual temperature rise times n is as follows:
n is an integer; wherein T is a planned heating target temperature, TaThe temperature of the forged piece before temperature rise;
holding time tiThe calculation formula of (2) is as follows: t is ti＝(10+2ni) min, wherein niFor the ith heating, ni＝i，i＝1,2…,n。
In the technical scheme, the temperature rising times, the temperature rising temperature and the heat preservation time are determined according to the wall thickness of the forging piece in a gradual temperature rising mode, so that the temperature uniformity of the thick-wall forging piece along the wall thickness direction in the temperature rising process can be ensured, and the temperature difference between the core temperature and the surface temperature is not more than 5 ℃.
Further, the gradual cooling mode in the step (5) is as follows: gradually cooling the forging piece for N times at a cooling speed of less than 50 ℃/h to reduce the temperature to a preset cooling target temperature, wherein the temperature is reduced by delta T each timejAnd is kept for a certain time t after each coolingj；
Wherein, Delta TjDetermining according to the wall thickness delta of the forged piece: when delta is less than 200mm, delta TjThe temperature is 200 ℃; when delta is more than or equal to 200mm and less than 300mm, delta Tj150 ℃ is set; when delta is more than or equal to 300mm and less than 400mm, delta Tj＝100℃；
The calculation formula of the gradual cooling times N is as follows:
taking an integer from N upwards; wherein, TbThe temperature before the temperature reduction of the forge piece is carried out, and T' is the set temperature target temperature;
holding time tjThe calculation formula of (2) is as follows: t is tj＝2(10+(N-2nj) Min, wherein n isjFor the j th heating, ni＝i，i＝1,2…,N。
In the technical scheme, the temperature reduction times, the temperature reduction temperature and the heat preservation time are determined according to the wall thickness of the forge piece in a gradual temperature reduction mode, and the temperature uniformity of the thick-wall forge piece in the wall thickness direction in the temperature reduction process can be ensured.
The beneficial effects of the invention are:
the regulating method provided by the invention aims at the ultra-thick forged piece of the large hydrogenation reactor, the synchronous regulation and control of the whole thickness structure-stress-performance of the forged piece can be realized, compared with the traditional method, the method breaks through the limitation that the traditional process can not regulate and control the core structure-stress-performance, the synchronous regulation and control of the structure, the performance and the stress of the forged piece with the thickness of 200-400 mm, even 500mm in the whole thickness direction can be realized, the forged piece can form a lower bainite structure in the whole thickness direction, the grain size can reach 8 grade, the uniformity of the structure performance is ensured, and the residual stress is reduced to be below 100 MPa; in addition, the temperature of the forging is not completely reduced after forging, but the temperature of the forging is kept at a high temperature for a period of time, so that the temperature in the full thickness direction is basically kept uniform, the structure of the forging is improved, crystal grains are refined, part of residual stress in the forging forming process is eliminated, the structure stress in the forging process is fully recovered, and the improvement of the structure, the performance and the stress of the forging by subsequent heat treatment is promoted; meanwhile, the long-time heating process after cooling is avoided, and the energy-saving and environment-friendly effects are achieved.
Drawings
FIG. 1 is a heat treatment process profile of example 1 of the present invention.
Detailed Description
The invention provides a method for regulating and controlling the whole-thickness structure-stress-performance uniformity of an ultra-thick forging of a large hydrogenation reactor, and the method is further explained in detail below in order to make the purpose, the technical scheme and the effect of the invention clearer and clearer. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.
The invention provides a full-thickness structure-stress-performance uniformity regulation and control method for an ultra-thick forging of a large hydrogenation reactor, which comprises the following steps:
(1) rapidly heating the steel ingot to 300-350 ℃, then heating to 650-700 ℃ at a heating rate of not more than 56 ℃/h, and preserving heat for 4-6 h; then heating the steel ingot to 800 +/-20 ℃ at a heating rate of less than 45 ℃/h, and preserving heat for 1-2 h; after the temperature is stable, heating the steel ingot to 900 +/-20 ℃ at the same heating rate, and preserving the heat for 1-2 hours; then, heating to 1000 +/-20 ℃ at the same heating rate, and preserving heat for 1-2 h; finally, heating to 1180 +/-10 ℃ at the same heating speed, and preserving heat for 2-4 hours;
(2) forging and forming the steel ingot within the steel ingot forging temperature range in the step (1), and controlling the forging finishing temperature to be not less than 850 ℃; controlling the temperature of the forge piece to be not less than 850 ℃ in the forging process, returning to the furnace to heat to 1180 +/-10 ℃ if the temperature is less than 850 ℃, and preserving heat for 1-2 hours;
(3) after the forging in the step (2) is completed, transferring the forged piece to a heat treatment furnace, cooling the forged piece to 700 +/-10 ℃ at a cooling speed of 20-30 ℃/h, and preserving heat for 15-20 h;
(4) on the basis of the step (3), heating to 1040-1080 ℃ in a gradual heating manner, and keeping for a certain time t1；
(5) Cooling to 660-720 ℃ in a gradual cooling way and keeping for a certain time t2(ii) a Then gradually cooling to 350-400 ℃, and naturally cooling to room temperature for rough machining;
(6) quenching treatment
After rough machining is finished, quickly heating to 400 ℃, then heating to 920-950 ℃ in a gradual heating mode, and keeping for a certain time t3(ii) a Then transferring the forged piece to a quenching bath, quenching the forged piece at a cooling speed of not less than 5 ℃/h, and cooling to 200-250 ℃ after quenching;
(7) transferring the quenched forged piece to a heat treatment furnace, slowly cooling to 200 +/-10 ℃, and keeping for 3-6 h; then gradually heating to 660-720 ℃, and keeping for a certain time t4(ii) a Finally, cooling to below 300 ℃ at a cooling speed of 20-30 ℃/h, and then discharging and air cooling;
said t is1＝(0.01δ+4)h，t2＝(0.04δ+2)h，t3＝(0.02δ+3)h，t4And d is (0.02 delta +10) h, delta is the wall thickness of the forged piece, and the unit of the wall thickness is mm.
The gradual temperature rise mode in the steps (4), (6) and (7) is as follows: gradually heating the forging piece at a heating rate of not more than 35 ℃/h for n times to raise the temperature to a planned heating target temperature, wherein the temperature is raised by delta T each timeiKeeping the temperature at a certain value for a certain time t after each temperature risei；
Wherein, Delta TiDetermining according to the wall thickness delta of the forged piece: when delta<At 200mm,. DELTA.Ti130 ℃ under normal temperature; when delta is more than or equal to 200mm and less than 300mm, delta TiThe temperature is 100 ℃; when delta is more than or equal to 300mm and less than 400mm, delta Ti＝80℃；
The calculation mode of the gradual temperature rise times n is as follows:
n is an integer; wherein T is a planned heating target temperature, TaThe temperature of the forged piece before temperature rise;
holding time tiThe calculation formula of (2) is as follows: t is ti＝(10+2ni) min, wherein niFor the ith heating, ni＝i，i＝1,2…,n。
The gradual cooling mode in the step (5) is as follows: gradually cooling the forging piece for N times at a cooling speed of less than 50 ℃/h to reduce the temperature to a preset cooling target temperature, wherein the temperature is reduced by delta T each timejAnd is kept for a certain time t after each coolingj；
Wherein, Delta TjDetermining according to the wall thickness delta of the forged piece: when delta is less than 200mm, delta TjThe temperature is 200 ℃; when delta is more than or equal to 200mm and less than 300mm, delta Tj150 ℃ is set; when delta is more than or equal to 300mm and less than 400mm, delta Tj＝100℃；
The calculation formula of the gradual cooling times N is as follows:
taking an integer from N upwards; wherein, TbThe temperature before the temperature reduction of the forge piece is carried out, and T' is the set temperature target temperature;
holding time tjThe calculation formula of (2) is as follows: t is tj＝2(10+(N-2nj) Min, wherein n isjFor the j th heating, ni＝i，i＝1,2…,N。
Example 1
Referring to FIG. 1, 2.25Cr-1Mo-0.25V steel materials are selected according to the regulation and control method to prepare test pieces, wherein the wall thickness is 350mm, the inner diameter is 200mm, and 2 test pieces are prepared. The specific process comprises the following steps:
(1) pretreatment before forging:
rapidly heating the steel ingot to 300 ℃ within 30min, preserving heat for 40min, then heating to 700 ℃ at the heating rate of 45 ℃/h, and preserving heat for 6 h; then heating the steel ingot to 800 ℃ at a heating rate of 30 ℃/h, and preserving heat for 1 h; after the temperature is stable, heating the steel ingot to 900 ℃ at the same heating rate, and preserving the heat for 1.5 h; then raising the temperature to 1000 ℃ at the same temperature raising speed, and preserving the temperature for 2 h; finally, heating to 1180 ℃ at the same heating speed, and preserving heat for 3 hours;
(2) forging and forming:
forging and molding the steel ingot to obtain a forging piece with the wall thickness of 350mm, wherein the final forging temperature is 960 ℃;
(3) pretreatment after forging:
rapidly transferring the forged piece with the initial temperature of 960 ℃ after forging forming to a heat treatment furnace, cooling the forged piece to 700 ℃ at the cooling speed of 20 ℃/h, and preserving heat for 20 h; after the step is finished, continuously performing the following step (4) on one hydrogenation reactor sample, performing air cooling on the other hydrogenation reactor sample, and detecting the residual stress after the temperature is reduced to the room temperature, wherein the surface residual stress is 212MPa, and the core residual stress is 230 MPa;
(4) full thickness tissue-stress-property recovery treatment:
after the heat preservation stage is completed, the temperature of the forge piece is gradually increased to 1050 ℃ at the temperature increasing speed of 30 ℃/h, specifically, the temperature is increased for 5 times, the temperature is increased for 80 ℃ for the first four times, the temperature is increased for 30 ℃ for the last time, the temperature is respectively preserved for 12min, 14min, 16min, 18min and 20min after each time of temperature increase, and then the temperature is preserved for 7.5h at 1050 ℃;
after the temperature preservation at 1050 ℃, the temperature of the forge piece is gradually reduced to 700 ℃ at a cooling speed of 40 ℃/h, specifically, the temperature is reduced for 4 times, the temperature is reduced for 100 ℃ in the first three times, the temperature is reduced for 50 ℃ in the last time, the temperature is respectively preserved for 24min, 20min, 16min and 12min after each time of temperature reduction, and then the temperature is preserved for 16h at 700 ℃;
after the heat preservation at 700 ℃, the forging is continuously cooled to 400 ℃ gradually at a cooling speed of 40 ℃/h, specifically, the temperature is reduced for 3 times, the temperature is reduced for 100 ℃ each time, the temperature is respectively preserved for 22min, 18min and 14min after each time of temperature reduction, and then the forging is naturally cooled to room temperature for rough machining;
after rough machining is finished, rapidly heating to 400 ℃, then gradually heating the forging to 930 ℃ at a heating rate of 30 ℃/h, specifically heating 7 times, wherein the temperature is increased by 80 ℃ for the first six times, and is increased by 50 ℃ for the last time, and after each heating, the temperature is respectively maintained for 12min, 14min, 16min, 18min, 20min, 22min and 24min, and then the temperature is maintained for 10h at 930 ℃;
after the thermal insulation at 930 ℃, transferring the forged piece into a rotary quenching bath, quenching the forged piece at a cooling speed of 5 ℃/h, and cooling to 200 ℃ after quenching;
transferring the quenched forging to a heat treatment furnace, slowly cooling to 150 ℃, and keeping for 5 hours;
then gradually heating the forging piece to 700 ℃ at the heating rate of 30 ℃/h, specifically heating for 7 times, heating for the first 6 times to 80 ℃, heating for the last time to 70 ℃, respectively preserving heat for 12min, 14min, 16min, 18min, 20min, 22min and 24min after each heating, and then preserving heat for 18h at 700 ℃;
and after the heat preservation at 700 ℃, cooling to below 300 ℃ at a cooling speed of 25 ℃/h, and then discharging from the furnace for air cooling to obtain a hydrogenation reactor sample.
Comparative example 1
The difference between the comparative example 1 and the example 1 is that after the forging is finished, the comparative example is directly and rapidly cooled to 300 ℃, then slowly cooled to 200 ℃ and kept warm for 6 hours; then gradually heating up to 1050 ℃ at the heating rate of 30 ℃/h and preserving heat for 7.5h, and the other steps are the same. In addition, 2 test pieces with the wall thickness of 350mm and the inner diameter of 200mm are also arranged in the comparative example 1, one test piece is subjected to the whole heat treatment process according to the method of the comparative example 1, the other test piece is firstly rapidly cooled to 300 ℃ after forging is completed, then is slowly cooled to 200 ℃ and is kept warm for 6 hours, then is air-cooled to room temperature, and the residual stress is detected after the temperature is reduced to the room temperature, wherein the surface residual stress is 320MPa, and the core residual stress is 346 MPa.
The above comparative example 1 is a currently used post-forging treatment method, and is usually subjected to rapid cooling directly after forging and then to heat treatment.
Comparative example 2
The comparative example 2 is provided with 1 test piece with the wall thickness of 350mm and the inner diameter of 200mm, and is different from the example 1 in that the comparative example does not adopt a method of gradually heating up and gradually cooling down in the step of full-thickness structure-stress-performance recovery treatment, only heats up or cools down at a certain speed, and other steps are the same, and the step of full-thickness structure-stress-performance recovery treatment is as follows:
heating the forging to 1050 ℃ at the heating rate of 30 ℃/h, and then preserving heat at 1050 ℃ for 7.5 h;
after the heat preservation at 1050 ℃, cooling the forging to 700 ℃ at the cooling speed of 40 ℃/h, and then preserving the heat for 16h at 700 ℃;
after the heat preservation at 700 ℃, continuously cooling the forging to 400 ℃ at the cooling speed of 40 ℃/h, and then naturally cooling to room temperature for rough machining;
after the rough machining is finished, quickly heating to 400 ℃, then heating the forge piece to 930 ℃ at the heating speed of 30 ℃/h, and then preserving heat at 930 ℃ for 10 h;
after the thermal insulation at 930 ℃, transferring the forged piece into a rotary quenching bath, quenching the forged piece at a cooling speed of 5 ℃/h, and cooling to 200 ℃ after quenching;
transferring the quenched forging to a heat treatment furnace, slowly cooling to 150 ℃, and keeping for 5 hours;
then heating the forging to 700 ℃ at the heating rate of 30 ℃/h, and then preserving heat at 700 ℃ for 18 h;
and after the heat preservation at 700 ℃, cooling to below 300 ℃ at a cooling speed of 25 ℃/h, and then discharging from the furnace for air cooling to obtain a hydrogenation reactor sample.
Comparative example 3
Comparative example 3 1 test piece with a wall thickness of 350mm and an internal diameter of 200mm was provided, which differs from example 1 in that: the pretreatment after forging in the step (3) and the full-thickness structure-stress-performance recovery treatment in the step (4) are different, and other steps are the same.
The post-forging pretreatment procedure in comparative example 3 was: directly and rapidly cooling to 300 ℃, then slowly cooling to 200 ℃ and keeping the temperature for 6 h.
The full thickness structure-stress-performance recovery processing steps in comparison 3 are as follows:
heating the forging to 1050 ℃ at the heating rate of 30 ℃/h, and then preserving heat at 1050 ℃ for 7.5 h;
after the heat preservation at 1050 ℃, cooling the forging to 700 ℃ at the cooling speed of 40 ℃/h, and then preserving the heat for 16h at 700 ℃;
after the heat preservation at 700 ℃, continuously cooling the forging to 400 ℃ at the cooling speed of 40 ℃/h, and then naturally cooling to room temperature for rough machining;
after rough machining is finished, rapidly heating to 400 ℃, then heating the forge piece to 930 ℃ at the heating speed of 30 ℃/h, and then preserving heat for 10h at 930 ℃;
after the thermal insulation at 930 ℃, transferring the forged piece into a rotary quenching bath, quenching the forged piece at a cooling speed of 5 ℃/h, and cooling to 200 ℃ after quenching;
transferring the quenched forging to a heat treatment furnace, slowly cooling to 150 ℃, and keeping for 5 hours;
then heating the forging to 700 ℃ at the heating rate of 30 ℃/h, and then preserving heat at 700 ℃ for 18 h;
and after the heat preservation at 700 ℃, cooling to below 300 ℃ at a cooling speed of 25 ℃/h, and then discharging from the furnace for air cooling to obtain a hydrogenation reactor sample. The full thickness sampling test was performed on the above example 1 and comparative examples 1 to 3, and the test results are shown in table 1. As can be seen from Table 1, the grain size of the product structure can reach 8 grades by the regulating method, the yield strength and the tensile strength are high, and particularly, the residual stress is low, which indicates that the heat preservation at about 700 ℃ after forging not only has the effects of grain refinement and product performance improvement, but also has a good residual stress eliminating effect; meanwhile, the invention adopts the modes of gradually heating and gradually cooling in the heating and cooling stages, so that the structure, the stress and the performance in the full thickness direction are uniform and consistent.
TABLE 1 Performance test data
The parts which are not described in the invention can be realized by adopting or referring to the prior art.
It is to be understood that the above description is not intended to limit the present invention, and the present invention is not limited to the above examples, and those skilled in the art may make modifications, alterations, additions or substitutions within the spirit and scope of the present invention.
Claims (5)
1. The method for regulating and controlling the whole-thickness structure-stress-performance uniformity of the ultra-thick forging of the large hydrogenation reactor is characterized by comprising the following steps of:
(1) rapidly heating the steel ingot to 300-350 ℃, then heating to 650-700 ℃ at a heating rate not more than 56 ℃/h, and preserving heat for 4-6 h; then, heating the steel ingot to 1180 +/-10 ℃ in sections, and preserving heat for 2-4 hours;
(2) forging and forming the steel ingot within the steel ingot forging temperature range in the step (1), and controlling the forging final temperature to be not less than 850 ℃;
(3) after the forging in the step (2) is completed, transferring the forged piece to a heat treatment furnace, cooling the forged piece to 700 +/-10 ℃ at a cooling speed of 20-30 ℃/h, and preserving heat for 15-20 h to ensure that the grain size of the forged piece reaches 6 grades or above and the residual stress is reduced to 200-260 MPa;
(4) on the basis of the step (3), heating to 1040-1080 ℃ in a gradual heating manner, and keeping for a certain time t1；
(5) Cooling to 660-720 ℃ in a gradual cooling way and keeping for a certain time t2(ii) a Then gradually cooling to 350-400 ℃, and naturally cooling to room temperature for rough machining;
(6) after rough machining is finished, quickly heating to 400 ℃, then heating to 920-950 ℃ in a gradual heating mode, and keeping for a certain time t3(ii) a Then transferring the forged piece to a quenching bath, quenching the forged piece at a cooling speed of not less than 5 ℃/h, and cooling to 200-250 ℃ after quenching so that the structural components of the forged piece in the full thickness direction are lower bainite;
(7) transferring the quenched forge piece to a heat treatment furnace, slowly cooling to 150 +/-10 ℃, and keeping for 3-6 hours; then gradually heating to 660-720 ℃, and keeping for a certain time t4(ii) a Finally cooling to below 300 ℃ at a cooling speed of 20-30 ℃/h, and dischargingAnd (5) performing air cooling in the furnace to reduce the residual stress of the forging in the full thickness direction to be less than 100 MPa.
Said t is1＝(0.01δ+4)h，t2＝(0.04δ+2)h，t3＝(0.02δ+3)h，t4δ is the forging wall thickness in mm (0.02 δ +10) h.
2. The method for regulating and controlling the whole-thickness structure-stress-performance uniformity of the ultra-thick forging of the large-scale hydrogenation reactor according to claim 1, wherein the step (1) comprises the following steps: heating the steel ingot to 800 +/-20 ℃ at a heating rate of less than 45 ℃/h, and preserving heat for 1-2 h; after the temperature is stable, heating the steel ingot to 900 +/-20 ℃ at the same heating speed, and preserving the heat for 1-2 hours; then, heating to 1000 +/-20 ℃ at the same heating rate, and preserving heat for 1-2 h; and finally, heating to 1180 +/-10 ℃ at the same heating speed, and preserving heat for 2-4 hours.
3. The method for regulating and controlling the whole-thickness structure-stress-performance uniformity of the ultra-thick forged piece of the large-sized hydrogenation reactor according to claim 1, wherein in the step (2), the temperature of the forged piece is controlled to be not less than 850 ℃ in the forging process, and if the temperature is less than 850 ℃, the temperature needs to be raised to 1180 +/-10 ℃ in a furnace, and the temperature is kept for 1-2 hours.
4. The method for regulating and controlling the whole-thickness structure-stress-performance uniformity of the ultra-thick forging of the large-scale hydrogenation reactor according to claim 1, wherein the gradual temperature rise in the steps (4), (6) and (7) is as follows: gradually heating the forging piece at a heating rate of not more than 35 ℃/h for n times to raise the temperature to a preset heating target temperature, wherein the temperature is raised by delta T every timeiKeeping the temperature at a certain value for a certain time t after each temperature risei；
Wherein, Delta TiDetermining according to the wall thickness delta of the forged piece: when delta<At 200mm,. DELTA.Ti130 deg.C; when delta is more than or equal to 200mm and less than 300mm, delta TiAt 100 deg.C; when delta is more than or equal to 300mm and less than 400mm, delta Ti＝80℃；
The calculation mode of the gradual temperature rise times n is as follows:
n is an integer upwards; wherein T is a planned heating target temperature, TaThe temperature of the forged piece before temperature rise;
holding time tiThe calculation formula of (2) is as follows: t is ti＝(10+2ni) min, wherein niFor the ith heating, ni＝i，i＝1,2…,n。
5. The method for regulating and controlling the whole-thickness structure-stress-performance uniformity of the ultra-thick forging of the large-scale hydrogenation reactor according to claim 1, wherein the gradual cooling mode in the step (5) is as follows: gradually cooling the forging piece for N times at a cooling speed of less than 50 ℃/h to reduce the temperature to a preset cooling target temperature, wherein the temperature is reduced by delta T each timejAnd is kept for a certain time t after each coolingj；
Wherein, Delta TjDetermining according to the wall thickness delta of the forged piece: when delta is less than 200mm, delta TjThe temperature is 200 ℃; when delta is more than or equal to 200mm and less than 300mm, delta Tj150 ℃ is set; when delta is more than or equal to 300mm and less than 400mm, delta Tj＝100℃；
The calculation formula of the gradual cooling times N is as follows:
taking an integer from N upwards; wherein, TbThe temperature before the temperature reduction of the forge piece is carried out, and T' is the set temperature target temperature;
holding time tjThe calculation formula of (2) is as follows: t is tj＝2(10+(N-2nj) Min, wherein njFor the j th heating, ni＝i，i＝1,2…,N。
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202210305337.8A CN114672631B (en) | 2022-03-25 | 2022-03-25 | Method for regulating and controlling full-thickness tissue-stress-performance uniformity of ultra-thick forging of large hydrogenation reactor |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202210305337.8A CN114672631B (en) | 2022-03-25 | 2022-03-25 | Method for regulating and controlling full-thickness tissue-stress-performance uniformity of ultra-thick forging of large hydrogenation reactor |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN114672631A true CN114672631A (en) | 2022-06-28 |
| CN114672631B CN114672631B (en) | 2023-11-21 |
Family
ID=82076019
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202210305337.8A Active CN114672631B (en) | 2022-03-25 | 2022-03-25 | Method for regulating and controlling full-thickness tissue-stress-performance uniformity of ultra-thick forging of large hydrogenation reactor |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN114672631B (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114833410A (en) * | 2022-07-05 | 2022-08-02 | 中机智能装备创新研究院(宁波)有限公司 | Method for reducing residual stress of heterogeneous brazed joint |
Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4444604A (en) * | 1983-03-07 | 1984-04-24 | United States Steel Corporation | Method of preventing distortion of a heated workpiece during cooling |
| CN105385814A (en) * | 2015-12-17 | 2016-03-09 | 二重集团（德阳）重型装备股份有限公司 | Thermal treatment method for tube section forging piece of hydrogenation reactor |
| WO2017206552A1 (en) * | 2016-06-03 | 2017-12-07 | 上海新闵（东台）重型锻造有限公司 | Monoblock forging of nuclear power steam generator housing and method for molding same by forging |
| CN109929981A (en) * | 2019-02-22 | 2019-06-25 | 无锡宏达重工股份有限公司 | The technique for optimizing 09MnNiD low-temperature impact work |
| CN111676351A (en) * | 2020-07-29 | 2020-09-18 | 中国石油大学(华东) | Heat treatment method for regulating residual stress by local temperature difference |
| CN113084060A (en) * | 2021-03-23 | 2021-07-09 | 上海腾辉锻造有限公司 | Small and medium forging piece made of 12Cr10Co3W2MoVNbNB steel and manufacturing method |
| CN113215383A (en) * | 2021-04-15 | 2021-08-06 | 无锡市捷安轧辊制造有限公司 | Heat treatment method for improving hardness and uniformity of casting roller sleeve |
| CN113881831A (en) * | 2021-10-08 | 2022-01-04 | 内蒙古北方重工业集团有限公司 | Post-forging heat treatment method for Cr-Mo-V type medium-carbon medium alloy steel |
Family Cites Families (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| FR2385809A1 (en) * | 1977-03-31 | 1978-10-27 | Forgeal Forgeage Estampage All | THERMAL TREATMENT AND QUENCHING PROCESS FOR FORGED PARTS |
| JP2000015379A (en) * | 1998-07-02 | 2000-01-18 | Daido Steel Co Ltd | Forging method of high carbon steel |
| CN107805759A (en) * | 2016-09-09 | 2018-03-16 | 中国石化工程建设有限公司 | A kind of low temperature pressure vessel steel plate and preparation method thereof |
| CN109622873B (en) * | 2018-12-27 | 2020-11-13 | 天津航天长征技术装备有限公司 | Manufacturing process of fine crystals of 2219 aluminum alloy ring piece |
| CN113215505B (en) * | 2021-03-22 | 2022-05-03 | 湖南大学 | Method for eliminating residual stress of annular special-shaped forge piece |
| CN113967717A (en) * | 2021-09-26 | 2022-01-25 | 江苏裕隆锻造有限公司 | Forging method for reducing defect cracks of 410 valve body forging |
-
2022
- 2022-03-25 CN CN202210305337.8A patent/CN114672631B/en active Active
Patent Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4444604A (en) * | 1983-03-07 | 1984-04-24 | United States Steel Corporation | Method of preventing distortion of a heated workpiece during cooling |
| CN105385814A (en) * | 2015-12-17 | 2016-03-09 | 二重集团（德阳）重型装备股份有限公司 | Thermal treatment method for tube section forging piece of hydrogenation reactor |
| WO2017206552A1 (en) * | 2016-06-03 | 2017-12-07 | 上海新闵（东台）重型锻造有限公司 | Monoblock forging of nuclear power steam generator housing and method for molding same by forging |
| CN109929981A (en) * | 2019-02-22 | 2019-06-25 | 无锡宏达重工股份有限公司 | The technique for optimizing 09MnNiD low-temperature impact work |
| CN111676351A (en) * | 2020-07-29 | 2020-09-18 | 中国石油大学(华东) | Heat treatment method for regulating residual stress by local temperature difference |
| CN113084060A (en) * | 2021-03-23 | 2021-07-09 | 上海腾辉锻造有限公司 | Small and medium forging piece made of 12Cr10Co3W2MoVNbNB steel and manufacturing method |
| CN113215383A (en) * | 2021-04-15 | 2021-08-06 | 无锡市捷安轧辊制造有限公司 | Heat treatment method for improving hardness and uniformity of casting roller sleeve |
| CN113881831A (en) * | 2021-10-08 | 2022-01-04 | 内蒙古北方重工业集团有限公司 | Post-forging heat treatment method for Cr-Mo-V type medium-carbon medium alloy steel |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114833410A (en) * | 2022-07-05 | 2022-08-02 | 中机智能装备创新研究院(宁波)有限公司 | Method for reducing residual stress of heterogeneous brazed joint |
| CN114833410B (en) * | 2022-07-05 | 2022-10-14 | 中机智能装备创新研究院(宁波)有限公司 | Method for reducing residual stress of heterogeneous brazed joint |
Also Published As
| Publication number | Publication date |
|---|---|
| CN114672631B (en) | 2023-11-21 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN110904312A (en) | Water-cooling quenching tempering process for large alloy steel forging | |
| CN106862272B (en) | Preparation method of high-strength high-ductility magnesium alloy plates | |
| CN110484701B (en) | Heat treatment process for high-toughness low-deformation-rate large-scale die-casting die steel | |
| US20230332261A1 (en) | Method for manufacturing equal-hardness cr5 back up roll | |
| CN114672631B (en) | Method for regulating and controlling full-thickness tissue-stress-performance uniformity of ultra-thick forging of large hydrogenation reactor | |
| CN103103326A (en) | Vacuum isothermal treatment technology for hot work die steel | |
| CN105543463B (en) | Atmosphere protection heat treatment process for ultrahigh-strength D6AC steel thin-wall pipe fitting | |
| CN110205572B (en) | Preparation method of two-phase Ti-Al-Zr-Mo-V titanium alloy forged rod | |
| CN107442721A (en) | A kind of warm and hot forging technique of mould | |
| CN114350903A (en) | Quenching cooling method of 5CrNiMoV module | |
| CN109022738B (en) | Preparation method of low-temperature impact resistant CrMo alloy steel forged circle | |
| CN111793742A (en) | Method for producing chrome-molybdenum steel plate by directly rolling steel ingot | |
| CN1218055C (en) | Therma processing method for crankshaft of high-power engine | |
| CN114317932B (en) | Heat treatment method for obtaining balanced state tissue of thick-wall high-cylinder ring forging | |
| CN114150114B (en) | Improved heat treatment method for welded pipe die steel | |
| CN110423961B (en) | Manufacturing method of metal spinning part | |
| CN115637370A (en) | Cold-work die steel for flame quenching | |
| CN114798999A (en) | Fine-grain high-strength-plasticity Ti80G forging and preparation method thereof | |
| CN111926152A (en) | Heat treatment deformation control method for large 23Co14Ni12Cr3MoE steel part | |
| CN115354119B (en) | Forging heat treatment method for secondary hardening profile steel | |
| CN118371635A (en) | Production method for improving low-power quality of 38CrMoAl forge piece | |
| CN114410894B (en) | Method for reducing quenching cracks of 12Cr2Mo1VR steel | |
| CN114941061B (en) | Heat treatment method for super-thick section hot work die steel forging | |
| CN112828214B (en) | Large 2219 aluminum alloy ring homogenizing rolling process | |
| CN116751939A (en) | Annealing method of large chromium-molybdenum-vanadium positive sixteen-edge steel ingot |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| TA01 | Transfer of patent application right | ||
| TA01 | Transfer of patent application right |
Effective date of registration: 20230116 Address after: 266580 No. 66 Changjiang West Road, Huangdao District, Qingdao, Shandong. Applicant after: CHINA University OF PETROLEUM (EAST CHINA) Applicant after: SINOPEC ENGINEERING Inc. Address before: 266580 No. 66 Changjiang West Road, Huangdao District, Qingdao, Shandong. Applicant before: CHINA University OF PETROLEUM (EAST CHINA) |
|
| GR01 | Patent grant | ||
| GR01 | Patent grant |