LCC steel production process and heat treatment device thereof

Abstract

The invention relates to the technical field of LCC steel production processes, in particular to an LCC steel production process which comprises the following steps: S1, smelting; s2, carrying out dephosphorization; s3, forging; s4, hot rolling; s5, cold rolling; and S6, heat treatment. The heat treatment device comprises a heat treatment furnace, a feeding part is arranged on the lower side of the heat treatment furnace, one side of the feeding part is connected with an auxiliary feeding part, and the auxiliary feeding part is used for providing division bars. In the LCC steel production process, normalizing and high-temperature tempering operation is conducted on the cold-rolled steel plates through the heat treatment device, manual placement of the steel plates is not needed, the multiple steel plates are evenly arranged at intervals, the problem that the steel plates are heated unevenly or temperature distribution is inconsistent in the heat treatment process is avoided, and the performance of finished products is guaranteed.

Description

Technical Field

[0001] The invention relates to the technical field of LCC steel production technology, in particular to an LCC steel production technology and a heat treatment device thereof. Background Art

[0002] The low-temperature, high-strength and toughened valve housing is a key control unit in the fluid material conveying system in the fields of petrochemical, nuclear power, metallurgy, medicine, food and national defense. Since it works in an environment of -40℃ to -196℃, this type of low-temperature valve housing must have good mechanical properties, low-temperature impact toughness, corrosion resistance and air tightness to ensure normal operation.

[0003] At present, the shell of this type of cryogenic valve is produced in the form of casting using low-carbon cryogenic steel (LCC steel). Since domestic valve design units pay more attention to the structural design of valves and ignore the basic research on cryogenic materials, the heat treatment method for valves produced with cryogenic steel is not very perfect, resulting in the low-temperature impact work of the valve being unqualified and showing a relatively low trend. As a result, there are prominent industry problems such as low product yield, long production cycle, high production cost, and low overall performance.

[0004] In the current LCC steel production process, cold-rolled steel plates need to be heat treated. In the existing processing process, multiple cold-rolled steel plates are stacked and placed inside a heat treatment device, resulting in certain differences in temperature changes between different cold-rolled steel plates, which affects the performance of the finished LCC steel.

[0005] Therefore, the present application provides an LCC steel production process and a heat treatment device thereof to solve the problem in the prior art that the temperature changes unevenly during the heat treatment of cold-rolled steel plates, affecting product performance. Summary of the invention

[0006] In order to solve the above problems, the present invention provides a LCC steel production process and a heat treatment device thereof.

[0007] The technical solution adopted by the present invention to solve the technical problem is: a LCC steel production process, comprising the following steps: S1. Smelting: adding scrap steel to the smelting part of the smelting device for smelting to obtain molten steel, the chemical composition of the molten steel is, by weight percentage, C0.13-0.18%, Mn0.50-0.60%, Ni0.16-0.20%, Sb0.05-0.08%, S<0.023%, P<0.05%, and the rest is Fe; S2. Dephosphorization: The molten steel is transported to the interior of the smelting device through a pipeline, the molten steel and the dephosphorization agent are stirred so that the molten steel and the dephosphorization agent are evenly contacted, and after the dephosphorization is completed, the temperature of the molten steel is adjusted to 1450-1500°C, and then the molten steel is poured into an ingot mold to obtain an ingot; The dephosphorization agent comprises magnesium oxide powder, calcium oxide powder and iron oxide powder in a ratio of 1:3:1; S3. Forging: Forging the steel ingot by hot forging process to obtain a continuous casting billet; S4. Hot rolling: The continuous casting billet is subjected to rough rolling, intermediate rolling and finish rolling, and then cut after cooling to obtain a hot-rolled steel plate; S5. Cold rolling: using a reversible single machine for rolling, a total of 4 passes to obtain a cold-rolled steel sheet; S6. Heat treatment: The cold-rolled steel sheet obtained in step S5 is added to a heat treatment device, adjacent cold-rolled steel sheets are separated by spacers, and heat treatment is performed in the form of normalizing + high-temperature tempering + quenching. After the heat treatment is completed, it can be cooled to room temperature.

[0008] As an optimization, the heat treatment process of step S6 specifically includes the following steps: A1. Normalizing: air cool the cold-rolled steel plate to 850-950℃, keep it warm for 3-6h, and then cool it down to 300-500℃ at a rate of 25-28℃; A2. High temperature tempering: heat the normalized steel to 600-800℃ at a rate of 25-30℃ / h, keep it at that temperature for 4-6h, and finally cool it to 150-300℃; A2. Quenching: Heat the steel plate after high temperature tempering at 28-32℃ to 950-1050℃, keep it warm for 1-6h, add it to quenching oil for quenching after it comes out of the furnace, and then cool it to room temperature.

[0009] The heat treatment device comprises a heat treatment furnace, a feeding part is arranged at the lower side of the heat treatment furnace, one side of the feeding part is connected to an auxiliary feeding part, and the auxiliary feeding part is used to provide spacers; The feeding part includes a feeding platform, and a connecting platform is connected to a side of the feeding platform away from the auxiliary feeding part. A guide assembly is provided on the outer side of the connecting platform, and an auxiliary material bin is connected to the outer end of the guide assembly. The auxiliary material bin includes an A state and a B state. The auxiliary material bin opens upward in the A state, and is close to the connecting platform in the B state, and the opening of the auxiliary material bin faces the feeding platform.

[0010] As an optimization, the guide assembly includes an arc-shaped guide rail, the interior of the guide rail is connected to an arc-shaped guide rod, the outside of the guide rail is connected to a drive motor, the output shaft of the drive motor is connected to a drive roller, the drive roller contacts the side wall of the guide rod, and the outer end of the guide rod is fixedly connected to the bottom of the auxiliary silo.

[0011] As an optimization, a limit push rod is provided at one end of the opening of the auxiliary silo away from the feeding platform, and the extended end of the limit push rod is flush with the opening of the auxiliary silo; The inner bottom of the auxiliary material bin is connected with a first telescopic rod, the first telescopic rod is connected with a first push plate, the first push plate is flush with the bottom surface of the auxiliary material bin, and the first push plate is arranged adjacent to the connecting platform.

[0012] As an optimization, one end of the connecting platform adjacent to the feeding platform is recessed to form a material guide trough, and an end of the material guide trough adjacent to the auxiliary material bin is provided with a material guide roller. A second telescopic rod is connected to the lower side of the connecting platform, and the extended end of the second telescopic rod is connected to the end of the material guide roller.

[0013] As an optimization, the bottom of the feeding platform is connected to a vertically arranged telescopic cylinder, a feeding opening is provided at the bottom of the heat treatment furnace, and the feeding platform is arranged opposite to the feeding opening.

[0014] As an optimization, the auxiliary feeding part includes at least two auxiliary guide rails, the upper end of the auxiliary guide rails is provided with a storage box for storing partitions, the partitions are arranged in a vertical arrangement in the storage box, an outlet is opened at the bottom of the storage box, and the outlet is arranged opposite to the auxiliary guide rails, the auxiliary guide rails include an inclined section connected to the storage box and a horizontal section adjacent to the connecting platform, and the horizontal section is lower than the inclined section; A third telescopic rod is provided on one side of the horizontal section away from the feeding platform, and the third telescopic rod is used to push the partition bars in the horizontal section to the feeding platform.

[0015] As an optimization, a baffle is provided on the outer side of the feeding platform, and a fourth telescopic rod is provided on the side of the feeding platform away from the connecting platform. The extended end of the fourth telescopic rod is connected to an auxiliary push plate, and the auxiliary push plate is arranged opposite to the side elevation of the connecting platform.

[0016] The present invention provides a LCC steel production process and a heat treatment device thereof, which has the following advantages: In the LCC steel production process of the present application, normalizing + high-temperature tempering operations are performed on the cold-rolled steel plates through a heat treatment device, and there is no need to manually place the steel plates, so that multiple steel plates are evenly spaced, avoiding uneven heating or inconsistent temperature distribution of the steel plates during the heat treatment process, thereby ensuring the performance of the finished product. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a schematic axial view of the heat treatment device of the present invention.

[0018] Figure 2 It is a schematic diagram of the bottom axial side of the heat treatment device of the present invention.

[0019] Figure 3 This is an axial side schematic diagram of a heat treatment device in which the heat treatment furnace is omitted in the present invention.

[0020] Figure 4 It is a schematic axial side view of the feeding part of the present invention.

[0021] Figure 5 It is a schematic diagram of the main view of the feeding part of the present invention.

[0022] Figure 6 It is a left schematic diagram of the feeding part of the present invention.

[0023] Figure 7 For the present invention Figure 6 Schematic diagram of the AA section structure.

[0024] Figure 8 For the present invention Figure 6 Schematic diagram of the BB cross-section structure.

[0025] Fig. 9 It is a schematic diagram of the placement state of the cold-rolled steel plate during the heat treatment process of the present invention.

[0026] Fig.10 For the present invention Fig. 9 Schematic diagram of the enlarged structure of part A.

[0027] Among them, 1. heat treatment furnace, 2. partition bar, 3. feeding platform, 4. connecting platform, 5. auxiliary silo, 6. guide rail, 7. guide rod, 8. driving motor, 9. limit push rod, 10. first telescopic rod, 11. first push plate, 12. material guide trough, 13. material guide roller, 14. second telescopic rod, 15. telescopic cylinder, 16. feeding opening, 17. auxiliary guide rail, 18. storage box, 19. third telescopic rod, 20. fourth telescopic rod, 21. auxiliary push plate, 22. second push plate, 23. fifth telescopic rod, 24. cold-rolled steel plate. DETAILED DESCRIPTION

[0028] In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inside", "outside", etc. indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, or the positions or positional relationships in which the product of the invention is usually placed when in use. They are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific position, be constructed and operated in a specific position, and therefore cannot be understood as limiting the present invention. In addition, the terms "first", "second", "third", etc. are only used to distinguish the description, and cannot be understood as indicating or implying relative importance.

[0029] The present solution also includes a controller, the position of which is set by the staff according to actual conditions during operation. The controller is used to control the electrical devices used in the present solution, including but not limited to sensors, motors, telescopic rods, water pumps, solenoid valves, heating wires, heat pumps, display screens, computer input devices, switch buttons, communication equipment, lights, speakers and microphones; the controller is an Intel processor, an AMD processor, a PLC controller, an ARM processor or a single-chip microcomputer, and the supporting components include a motherboard, a memory stick, a storage medium and a power supply, and the power supply is AC power or a lithium battery; when a display screen is provided, a display card is also provided.

[0030] Embodiment 1: A LCC steel production process comprises the following steps: S1. Smelting: adding scrap steel to the smelting part of the smelting device for smelting to obtain molten steel, the chemical composition of the molten steel is, by weight percentage, C0.13%, Mn0.50%, Ni0.16%, Sb0.05%, S0.02%, P0.03%, and the rest is Fe; S2. Dephosphorization: The molten steel is transported to the interior of the smelting device through a pipeline, the molten steel and the dephosphorization agent are stirred so that the molten steel and the dephosphorization agent are evenly contacted, and after the dephosphorization is completed, the temperature of the molten steel is adjusted to 1450°C, and then the molten steel is poured into an ingot mold to obtain an ingot; The dephosphorization agent comprises magnesium oxide powder, calcium oxide powder and iron oxide powder in a ratio of 1:3:1; S3. Forging: Forging the steel ingot by hot forging process to obtain a continuous casting billet; S4. Hot rolling: The continuous casting billet is subjected to rough rolling, intermediate rolling and finish rolling, and then cut after cooling to obtain a hot-rolled steel plate; S5. Cold rolling: using a reversible single machine for rolling, a total of 4 passes to obtain a cold-rolled steel sheet 24; S6. Heat treatment: The cold-rolled steel sheet 24 obtained in step S5 is added to a heat treatment device, and adjacent cold-rolled steel sheets 24 are separated by spacers 2. Heat treatment is performed in the form of normalizing + high-temperature tempering + quenching, and the sheet is cooled to room temperature after the heat treatment is completed.

[0031] The heat treatment process of step S6 specifically includes the following steps: A1. Normalizing: air cool the cold-rolled steel plate to 850℃, keep it warm for 3h, and then cool it down to 300℃ at a rate of 25℃; A2. High temperature tempering: heat the normalized steel to 600℃ at a rate of 25℃ / h, keep it at that temperature for 4h, and finally cool it to 150℃; A2. Quenching: Heat the steel plate after high temperature tempering from 28℃ to 950℃, keep it warm for 1h, add it into quenching oil for quenching after it comes out of the furnace, and then cool it to room temperature.

[0032] Embodiment 2: A LCC steel production process comprises the following steps: S1. Smelting: adding scrap steel to the smelting part of the smelting device for smelting to obtain molten steel, the chemical composition of the molten steel is, by weight percentage, C0.18%, Mn0.60%, Ni0.20%, Sb0.08%, S0.17%, P0.03%, and the rest is Fe; S2. Dephosphorization: The molten steel is transported to the interior of the smelting device through a pipeline, the molten steel and the dephosphorization agent are stirred so that the molten steel and the dephosphorization agent are evenly contacted, and after the dephosphorization is completed, the temperature of the molten steel is adjusted to 1500°C, and then the molten steel is poured into an ingot mold to obtain an ingot; The dephosphorization agent comprises magnesium oxide powder, calcium oxide powder and iron oxide powder in a ratio of 1:3:1; S3. Forging: Forging the steel ingot by hot forging process to obtain a continuous casting billet; S4. Hot rolling: The continuous casting billet is subjected to rough rolling, intermediate rolling and finish rolling, and then cut after cooling to obtain a hot-rolled steel plate; S5. Cold rolling: using a reversible single machine for rolling, a total of 4 passes to obtain a cold-rolled steel sheet 24; S6. Heat treatment: The cold-rolled steel sheet 24 obtained in step S5 is added to a heat treatment device, and adjacent cold-rolled steel sheets 24 are separated by spacers 2. Heat treatment is performed in the form of normalizing + high-temperature tempering + quenching, and the sheet is cooled to room temperature after the heat treatment is completed.

[0033] The heat treatment process of step S6 specifically includes the following steps: A1. Normalizing: air cool the cold-rolled steel plate to 950℃, keep it warm for 6h, and then cool it down to 500℃ at a rate of 28℃; A2. High temperature tempering: The normalized steel is heated to 800℃ at a rate of 30℃ / h, kept at this temperature for 6h, and finally cooled to 300℃; A2. Quenching: Heat the steel plate after high temperature tempering from 32℃ to 1050℃, keep it warm for 6h, add it into quenching oil for quenching after it comes out of the furnace, and then cool it to room temperature.

[0034] Embodiment 3: A LCC steel production process comprises the following steps: S1. Smelting: adding scrap steel to the smelting part of the smelting device for smelting to obtain molten steel, the chemical composition of the molten steel is, by weight percentage, C0.15%, Mn0.55%, Ni0.18%, Sb0.06%, S0.021%, P0.04%, and the rest is Fe; S2. Dephosphorization: The molten steel is transported to the interior of the smelting device through a pipeline, the molten steel and the dephosphorization agent are stirred so that the molten steel and the dephosphorization agent are evenly contacted, and after the dephosphorization is completed, the temperature of the molten steel is adjusted to 1480°C, and then the molten steel is poured into an ingot mold to obtain an ingot; The dephosphorization agent comprises magnesium oxide powder, calcium oxide powder and iron oxide powder in a ratio of 1:3:1; S3. Forging: Forging the steel ingot by hot forging process to obtain a continuous casting billet; S4. Hot rolling: The continuous casting billet is subjected to rough rolling, intermediate rolling and finish rolling, and then cut after cooling to obtain a hot-rolled steel plate; S5. Cold rolling: using a reversible single machine for rolling, a total of 4 passes to obtain a cold-rolled steel sheet 24; S6. Heat treatment: The cold-rolled steel sheet 24 obtained in step S5 is added to a heat treatment device, and adjacent cold-rolled steel sheets 24 are separated by spacers 2. Heat treatment is performed in the form of normalizing + high-temperature tempering + quenching, and the sheet is cooled to room temperature after the heat treatment is completed.

[0035] The heat treatment process of step S6 specifically includes the following steps: A1. Normalizing: air cool the cold-rolled steel plate to 900℃, keep it warm for 4h, and then cool it down to 400℃ at a rate of 27℃; A2. High temperature tempering: The normalized steel is heated to 700℃ at a rate of 28℃ / h, kept at this temperature for 5h, and finally cooled to 230℃; A2. Quenching: Heat the steel plate after high temperature tempering from 30℃ to 1000℃, keep it warm for 4h, add it into quenching oil for quenching after it comes out of the furnace, and then cool it to room temperature.

[0036] Comparative Example 1: A LCC steel production process comprises the following steps: S1. Smelting: adding scrap steel to the smelting part of the smelting device for smelting to obtain molten steel, the chemical composition of the molten steel is, by weight percentage, C0.13%, Mn0.50%, Ni0.16%, Sb0.05%, S0.02%, P0.03%, and the rest is Fe; S2. Dephosphorization: The molten steel is transported to the interior of the smelting device through a pipeline, the molten steel and the dephosphorization agent are stirred so that the molten steel and the dephosphorization agent are evenly contacted, and after the dephosphorization is completed, the temperature of the molten steel is adjusted to 1450°C, and then the molten steel is poured into an ingot mold to obtain an ingot; The dephosphorization agent comprises magnesium oxide powder, calcium oxide powder and iron oxide powder in a ratio of 1:3:1; S3. Forging: Forging the steel ingot by hot forging process to obtain a continuous casting billet; S4. Hot rolling: The continuous casting billet is subjected to rough rolling, intermediate rolling and finish rolling, and then cut after cooling to obtain a hot-rolled steel plate; S5. Cold rolling: using a reversible single machine for rolling, a total of 4 passes to obtain a cold-rolled steel sheet 24; S6. Heat treatment: The cold-rolled steel sheet 24 obtained in step S5 is added to the heat treatment furnace 1 and heat treated in the form of normalizing + high temperature tempering + quenching. After the heat treatment is completed, it is cooled to room temperature.

[0037] The heat treatment process of step S6 specifically includes the following steps: A1. Normalizing: air cool the cold-rolled steel plate to 850℃, keep it warm for 3h, and then cool it down to 300℃ at a rate of 25℃; A2. High temperature tempering: heat the normalized steel to 600℃ at a rate of 25℃ / h, keep it at that temperature for 4h, and finally cool it to 150℃; A2. Quenching: Heat the steel plate after high temperature tempering from 28℃ to 950℃, keep it warm for 1h, add it into quenching oil for quenching after it comes out of the furnace, and then cool it to room temperature.

[0038] Tensile strength N / mm2 Lower yield N / mm2 Elongation after fracture % Section shrinkage % Low temperature impact energy at -46℃ (average value of three samples J)

[0039] like Figure 1-10 As shown, the heat treatment device comprises a heat treatment furnace 1, a feeding part is arranged at the lower side of the heat treatment furnace 1, one side of the feeding part is connected to an auxiliary feeding part, and the auxiliary feeding part is used to provide the spacer 2; The feeding part includes a feeding platform 3, and a connecting platform 4 is connected to the side of the feeding platform 3 away from the auxiliary feeding part. A guide component is provided on the outer side of the connecting platform 4, and an auxiliary silo 5 is connected to the outer end of the guide component. The auxiliary silo 5 includes an A state and a B state. The auxiliary silo 5 opens upward in the A state, and is close to the connecting platform 4 in the B state, and the opening of the auxiliary silo 5 faces the feeding platform 3.

[0040] The cold-rolled steel sheets 24 are stacked on the feeding platform 3, and the feeding platform 3 pushes the cold-rolled steel sheets 24 upward to the inside of the heat treatment furnace 1. Fig. 9 Placed in the state shown.

[0041] The guide assembly is used to drive and support the auxiliary silo 5. The side of the auxiliary silo 5 away from the connecting platform 4 is a movable surface. In order to facilitate the placement of the cold-rolled steel plate 24, the movable surface can be rotated and unfolded outward.

[0042] like Figure 1As shown, the guide assembly includes an arc-shaped guide rail 6, the interior of the guide rail 6 is connected to an arc-shaped guide rod 7, the exterior of the guide rail 6 is connected to a drive motor 8, the output shaft of the drive motor 8 is connected to a drive roller, the drive roller is in contact with the side wall of the guide rod 7, and the outer end of the guide rod 7 is fixedly connected to the bottom of the auxiliary silo 5.

[0043] When the guide rod 7 extends outwards along the guide track 6 , it can drive the auxiliary silo 5 to rotate toward the connecting platform 4 .

[0044] like Figure 7 As shown, a limiting push rod 9 is provided at one end of the opening of the auxiliary silo 5 away from the feeding platform 3, and the extended end of the limiting push rod 9 is flush with the opening of the auxiliary silo 5; The inner bottom of the auxiliary silo 5 is connected to a first telescopic rod 10 , the first telescopic rod 10 is connected to a first push plate 11 , the first push plate 11 is flush with the bottom surface of the auxiliary silo 5 , and the first push plate 11 is disposed adjacent to the connecting platform 4 .

[0045] When the auxiliary silo 5 is in state A, the cold-rolled steel plates 24 are arranged in a vertical arrangement, and the limit push rod 9 is horizontally placed at the opening of the auxiliary silo 5 to limit the cold-rolled steel plates 24 and prevent the cold-rolled steel plates 24 from escaping from the auxiliary silo 5 in state B. When the limit push rod 9 is extended, the extended end of the limit push rod 9 is located in the middle of the opening of the auxiliary silo 5.

[0046] like Figure 7 As shown, one end of the connecting platform 4 adjacent to the feeding platform 3 is recessed to form a material guide trough 12, and one end of the material guide trough 12 adjacent to the auxiliary silo 5 is provided with a material guide roller 13. A second telescopic rod 14 is connected to the lower side of the connecting platform 4, and the extended end of the second telescopic rod 14 is connected to the end of the material guide roller 13.

[0047] The opening of the auxiliary silo 5 is arranged adjacent to the guide roller 13. When the cold-rolled steel plate 24 is pushed outward from the inside of the auxiliary silo 5, it enters the guide groove 12 after being guided by the guide roller 13. When the second telescopic rod 14 is extended, the guide roller 13 extends upward from the bottom to limit the cold-rolled steel plate 24 on the right side of the guide roller 13, and at the same time can guide the cold-rolled steel plate 24 on the left side to prevent the cold-rolled steel plate 24 from falling quickly and causing deformation.

[0048] like Figure 2 As shown, a vertically arranged telescopic cylinder 15 is connected to the bottom of the feeding platform 3 , a feeding opening 16 is provided at the bottom of the heat treatment furnace 1 , and the feeding platform 3 is arranged opposite to the feeding opening 16 .

[0049] like Figure 3As shown, the auxiliary feeding part includes at least two auxiliary guide rails 17, and a storage box 18 for storing the partition bars 2 is arranged at the upper end of the auxiliary guide rail 17. The partition bars 2 are arranged in the storage box 18 in an up-and-down manner. An outlet is opened at the bottom of the storage box 18, and the outlet is arranged opposite to the auxiliary guide rail 17. The auxiliary guide rail 17 includes an inclined section connected to the storage box 18 and a horizontal section adjacent to the connecting platform 4, and the horizontal section is lower than the inclined section; A third telescopic rod 19 is provided on one side of the horizontal section away from the feeding platform 3 , and the third telescopic rod 19 is used to push the partition bar 2 in the horizontal section to the feeding platform 3 .

[0050] The two auxiliary guide rails 17 are arranged in parallel, and the inner walls of the auxiliary guide rails 17 are smooth.

[0051] like Figure 3 As shown, a baffle is provided on the outer side of the feeding platform 3, and a fourth telescopic rod 20 is provided on the side of the feeding platform 3 away from the connecting platform 4. The extended end of the fourth telescopic rod 20 is connected to an auxiliary push plate 21, and the auxiliary push plate 21 is arranged opposite to the side elevation of the connecting platform 4.

[0052] The fourth telescopic rod 20 drives the auxiliary push plate 21 to move, so as to push and align the cold-rolled steel plate 24 on the feeding platform 3 .

[0053] When the device is used, the auxiliary material bin 5 is set in the A state, the cold-rolled steel plate 24 is stacked inside the auxiliary material bin 5, and the limit push rod 9 is extended to limit the cold-rolled steel plate 24; The guide rod 7 is driven by the driving motor 8 to move along the guide track 6, so that the auxiliary bin 5 is placed on the connecting platform 4 in the B state, and the limiting push rod 9 is shortened to the upper part of the opening of the auxiliary bin 5; The first telescopic rod 10 is extended, and the lower part of the cold-rolled steel plate 24 is pushed to move toward the guide groove 12 through the first push plate 11. Figure 7 As shown, the outermost cold-rolled steel sheet 24 is guided by the guide roller 13 and then moved onto the guide trough 12; The fifth telescopic rod 23 is extended, and the lower part of the cold-rolled steel plate 24 is pushed to move toward the feeding platform 3 through the second push plate 22. At the same time, the second telescopic rod 14 is extended, and the upper part of the cold-rolled steel plate 24 is guided through the guide roller 13, so that the cold-rolled steel plate 24 is slowly moved onto the feeding platform 3, until the second push plate 22 completely pushes the cold-rolled steel plate 24 onto the feeding platform 3; The third telescopic rod 19 is extended to push the spacer bar 2 onto the cold-rolled steel plate 24, and at the same time, the fourth telescopic rod 20 is extended to align the cold-rolled steel plate 24 and the spacer bar 2 on the feeding platform 3 through the auxiliary push rod; The telescopic cylinder 15 is shortened so that the top of the partition bar 2 is flush with the upper surface of the guide trough 12, which is convenient for the next cold-rolled steel plate 24 to be placed.

[0054] The above-mentioned specific embodiments are only specific cases of the present invention. The patent protection scope of the present invention includes but is not limited to the product form and style of the above-mentioned specific embodiments. Any LCC steel production process and heat treatment device thereof that conform to the claims of the present invention and any appropriate changes or modifications made thereto by ordinary technicians in any corresponding technical field shall fall within the patent protection scope of the present invention.

Claims

1. A LCC steel production process, characterized in that: The steps include: S1. Smelting: adding scrap steel to the smelting part of the smelting device for smelting to obtain molten steel, the chemical composition of the molten steel is, by weight percentage, C0.13-0.18%, Mn0.50-0.60%, Ni0.16-0.20%, Sb0.05-0.08%, S<0.023%, P<0.05%, and the rest is Fe; S2. Dephosphorization: The molten steel is transported to the interior of the smelting device through a pipeline, the molten steel and the dephosphorization agent are stirred so that the molten steel and the dephosphorization agent are evenly contacted, and after the dephosphorization is completed, the temperature of the molten steel is adjusted to 1450-1500°C, and then the molten steel is poured into an ingot mold to obtain an ingot; The dephosphorization agent comprises magnesium oxide powder, calcium oxide powder and iron oxide powder in a ratio of 1:3:1; S3. Forging: Forging the steel ingot by hot forging process to obtain a continuous casting billet; S4. Hot rolling: The continuous casting billet is subjected to rough rolling, intermediate rolling and finish rolling, and then cut after cooling to obtain a hot-rolled steel plate; S5. Cold rolling: using a reversible single machine for rolling, a total of 4 passes to obtain a cold-rolled steel sheet; S6. Heat treatment: The cold-rolled steel sheet obtained in step S5 is added to a heat treatment device, and adjacent cold-rolled steel sheets are separated by spacers (2). Heat treatment is performed in the form of normalizing + high-temperature tempering + quenching, and the sheet is cooled to room temperature after the heat treatment is completed.

2. A LCC steel production process according to claim 1, characterized in that: The heat treatment process of step S6 specifically includes the following steps: A1. Normalizing: air cool the cold-rolled steel plate to 850-950℃, keep it warm for 3-6h, and then cool it down to 300-500℃ at a rate of 25-28℃; A2. High temperature tempering: heat the normalized steel to 600-800℃ at a rate of 25-30℃ / h, keep it at that temperature for 4-6h, and finally cool it to 150-300℃; A2. Quenching: Heat the steel plate after high temperature tempering at 28-32℃ to 950-1050℃, keep it warm for 1-6h, add it to quenching oil for quenching after it comes out of the furnace, and then cool it to room temperature.

3. A heat treatment device for producing the LCC steel according to any one of claims 1 to 2, characterized in that: It comprises a heat treatment furnace (1), wherein a feeding part is arranged at the lower side of the heat treatment furnace (1), and an auxiliary feeding part is connected to one side of the feeding part, wherein the auxiliary feeding part is used to provide spacers (2); The feeding part comprises a feeding platform (3), a side of the feeding platform (3) away from the auxiliary feeding part is connected to a connecting platform (4), a guide assembly is provided on the outer side of the connecting platform (4), an outer end of the guide assembly is connected to an auxiliary material bin (5), the auxiliary material bin (5) comprises an A state and a B state, the auxiliary material bin (5) opens upward in the A state, and the auxiliary material bin (5) is close to the connecting platform (4) in the B state and the opening of the auxiliary material bin (5) faces the feeding platform (3).

4. A heat treatment device according to claim 3, characterized in that: The guide assembly comprises an arc-shaped guide rail (6), the interior of the guide rail (6) is connected to an arc-shaped guide rod (7), the exterior of the guide rail (6) is connected to a drive motor (8), the output shaft of the drive motor (8) is connected to a drive roller, the drive roller contacts the side wall of the guide rod (7), and the outer end of the guide rod (7) is fixedly connected to the bottom of the auxiliary silo (5).

5. A heat treatment device according to claim 3, characterized in that: A limiting push rod (9) is provided at one end of the opening of the auxiliary silo (5) away from the feeding platform (3), and the extended end of the limiting push rod (9) is flush with the opening of the auxiliary silo (5); The inner bottom of the auxiliary material bin (5) is connected to a first telescopic rod (10), the first telescopic rod (10) is connected to a first push plate (11), the first push plate (11) is flush with the bottom surface of the auxiliary material bin (5), and the first push plate (11) is arranged adjacent to the connecting platform (4).

6. A heat treatment device according to claim 3, characterized in that: One end of the connecting platform (4) adjacent to the feeding platform (3) is recessed to form a material guide trough (12), and one end of the material guide trough (12) adjacent to the auxiliary material bin (5) is provided with a material guide roller (13). A second telescopic rod (14) is connected to the lower side of the connecting platform (4), and an extended end of the second telescopic rod (14) is connected to the end of the material guide roller (13).

7. A heat treatment device according to claim 3, characterized in that: The bottom of the feeding platform (3) is connected to a vertically arranged telescopic cylinder (15), the bottom of the heat treatment furnace (1) is provided with a feeding opening (16), and the feeding platform (3) and the feeding opening (16) are arranged opposite to each other.

8. A heat treatment device according to claim 3, characterized in that: The auxiliary feeding part comprises at least two auxiliary guide rails (17), the upper end of the auxiliary guide rail (17) is provided with a storage box (18) for storing the partition bars (2), the partition bars (2) are arranged in an upper and lower manner in the storage box (18), and an outlet is opened at the bottom of the storage box (18), and the outlet is arranged opposite to the auxiliary guide rail (17), and the auxiliary guide rail (17) comprises an inclined section connected to the storage box (18) and a horizontal section adjacent to the connecting platform (4), and the horizontal section is lower than the inclined section; A third telescopic rod (19) is provided on the side of the horizontal section away from the feeding platform (3), and the third telescopic rod (19) is used to push the partition bar (2) in the horizontal section to the feeding platform (3).

9. A heat treatment device according to claim 3, characterized in that: A baffle is provided on the outer side of the feeding platform (3), and a fourth telescopic rod (20) is provided on the side of the feeding platform (3) away from the connecting platform (4). The extended end of the fourth telescopic rod (20) is connected to an auxiliary push plate (21), and the auxiliary push plate (21) is arranged opposite to the side elevation of the connecting platform (4).

Images