Manufacturing method of hot-rolled checkered steel plate roller

Abstract

The invention belongs to the technical field of casting, and particularly relates to a manufacturing method of a hot-rolled checkered steel plate roller, a roller body comprises a working layer and a core layer, and the working layer is made of needle-shaped bainite nodular cast iron; the core layer is made of nodular cast iron; before the working layer molten iron is discharged out of the furnace, a modified alloy material with the working layer molten iron amount smaller than 0.8% is pre-added to the bottom of the ladle, and the working layer molten iron is added for modification treatment; when half of the working layer molten iron is discharged from the furnace, silicon iron or silicon barium lump materials with the amount smaller than 1.0% of the working layer molten iron are added into the molten iron ladle, and inoculation treatment is conducted on the alloy molten iron; before the core layer molten iron is discharged from the furnace, adding a spheroidizing agent which is less than 2.0% of the core layer molten iron into the ladle bottom of the dam, covering the upper part with silicon iron or silicon barium lump materials which are less than 2.0% of the core layer molten iron, and adding the core layer molten iron for spheroidizing. The working layer molten iron is subjected to modification treatment to obtain a spherical or dotted graphite form; the bainite morphology is controlled through heat treatment, finally, needle-shaped bainite is obtained on a roller working layer, and meanwhile growth of graphite in a metal matrix structure is restrained.

Description

Technical Field

[0001] The invention belongs to the technical field of casting, and in particular relates to a method for manufacturing a hot-rolled patterned steel plate roller. Background Art

[0002] Checkered plates are aesthetically pleasing, have excellent anti-slip properties, and are easy to clean. They are widely used in construction, transportation, machinery manufacturing, shipbuilding, public spaces, and other fields. The GB / T 3277 standard clearly stipulates that the surface quality requirements for checkered steel plates / strips do not allow for rolling bubbles, scars, cracks, folds, inclusions, or delamination. For ordinary precision checkered steel plates, a thin layer of scale, rust, and surface roughness caused by the shedding of scale are permitted. However, for higher precision checkered steel plates, a thin layer of scale, rust, and other local defects whose height and depth do not exceed half the thickness tolerance are permitted. The pattern should be intact. Even if the pattern is incomplete, any minor local burrs should not exceed half the thickness tolerance in height.

[0003] Hot-rolled patterned steel plate rollers are subjected to enormous rolling forces during the high-temperature and high-pressure rolling process, and pattern edge flaking accidents are common. Therefore, the rollers are required to have not only sufficient strength and toughness to maintain the ability to resist pattern edge flaking and thermal cracking, but also high thermal stability to avoid deformation or failure during rolling service.

[0004] Rollers are classified by material into cast iron rolls and cast steel rolls. Engraved rolls are less smooth than plain rolls, leading to greater friction between the patterned plate and the rolls. This prevents the strip from separating from the rolls, making it more likely that the workpiece will wrap around the rolls, potentially causing serious production accidents.

[0005] To address this issue, the top roll is designed with a positive crown pattern, while the bottom roll is negatively crowned. The combination of positive and negative crowns on the top and bottom rolls facilitates the separation of the patterned plate from the patterned rolls. If the rolls are designed with corrosion resistance and rolling friction reduction features, the stability of the patterned plate rolling process will be further enhanced.

[0006] For hot-rolled patterned steel rolls, hardness is the most important quality characteristic. Generally speaking, the higher the roll hardness, the better the wear resistance. However, excessive hardness can cause premature cracking or flaking during use and increase the difficulty of roll engraving. Summary of the Invention

[0007] The technical problem to be solved by the present invention is to provide a method for manufacturing a hot-rolled patterned steel plate roller, select the best roller material, and determine the appropriate metal matrix structure; use the molten iron smelting inoculation and metamorphism treatment technology to effectively control the graphite morphology in the roller metal matrix structure; through the roller heat treatment control means, obtain the best roller metal matrix structure, the roller hardness is moderate, easy to engrave processing, the roller is wear-resistant, has good toughness, and strong resistance to thermal cracking.

[0008] To achieve the above objectives, the present invention adopts the following technical solutions:

[0009] A method for manufacturing a hot-rolled patterned steel plate roller comprises the following steps:

[0010] 1) The roll body includes a working layer and a core layer. The working layer is made of acicular bainite ductile iron with the following chemical composition by mass fraction: C: 2.90-3.60; Si: 0.60-1.50; Mn: 0.40-1.20; P≤0.10; S≤0.05; Ni: 3.01-4.80; Cr: 1.0-3.0; Mo: 0.2-1.0; V+W+Nb<1.0; Mg+Re≥0.02;

[0011] The core material is ductile iron, with the following chemical composition by mass fraction: C: 2.50-3.30; Si: 2.0-3.0; Mn: 0.40-1.20; P≤0.05; S≤0.02; Ni≤1.5; Cr+Mo+V+W+Nb≤0.80; Mg+Re≥0.04;

[0012] 2) Molten iron smelting: The outer layer and core layer molten iron are smelted in the smelting furnace;

[0013] 3) Molten iron treatment:

[0014] ① Before the working layer molten iron is discharged from the furnace, a modified alloy material of less than 0.8% of the working layer molten iron is pre-added to the bottom of the molten iron ladle and added to the working layer molten iron for modification treatment; when the working layer molten iron is half discharged from the furnace, ferrosilicon or silicon-barium alloy granules of less than 1.0% of the working layer molten iron are added to the molten iron ladle to inoculate the alloy molten iron;

[0015] ② Before the core layer molten iron is discharged from the furnace, a spheroidizing agent of less than 2.0% of the core layer molten iron is added to the bottom of the dam, and the upper part is covered with ferrosilicon or silicon-barium alloy blocks of less than 2.0% of the core layer molten iron, and the core layer molten iron is added for spheroidizing treatment;

[0016] 4) Roller casting:

[0017] ① Start the centrifuge, and the centrifugal gravity of the inner surface of the centrifugal cooling type reaches 40-150g;

[0018] ② Clean the slag from the working layer and pour molten iron into the roll working layer when the molten iron temperature reaches 1300-1420℃;

[0019] ③After the working layer molten iron is poured, immediately add protective slag from both ends of the cold mold. When the inner surface temperature of the molten iron in the working layer of the roll reaches 800-1180℃, reduce the speed and stop the centrifuge;

[0020] ④ Lift the cold mold and place it vertically above the base box, then buckle the riser box onto the cold mold;

[0021] ⑤ The core iron pouring temperature is controlled at 1320-1400℃. When the roll core is poured, ferrosilicon or silicon-barium alloy particles less than 5.0% of the core iron are added into the pouring hopper to perform instant inoculation treatment on the core iron.

[0022] ⑥After the roller core filling operation is completed, remove the pouring funnel and cover the upper part of the riser with insulation material;

[0023] ⑦The rollers are cooled naturally in the casting trench;

[0024] 5) Roll cooling and unpacking: unpack the rolls after cooling for more than 48 hours, and ensure that the roll body temperature is less than 100°C;

[0025] 6) Roller heat treatment:

[0026] ①Temperature rise <20℃ / h;

[0027] ②When the roller body temperature reaches 230-550℃, keep it warm for 10-30h;

[0028] ③ Cool down the kiln at a rate of less than 20°C / h. When the roller body temperature is less than 150°C, take the rolls out of the kiln and store them in a dry place.

[0029] In step 3), the temperature of the molten iron in the working layer is less than 1580°C; the temperature of the molten iron in the core layer is less than 1500°C.

[0030] In step 3) ②, the particle size of the ferrosilicon or silicon-barium alloy block material is 20 to 30 mm.

[0031] In step 3) ①, the modified alloy material is a silicon-calcium alloy, a silicon-zirconium alloy, a rare earth magnesium alloy or a pure magnesium alloy.

[0032] In step 3) ②, the spheroidizing agent is a rare earth magnesium alloy, a nickel magnesium alloy or a yttrium-based heavy rare earth.

[0033] The particle size of the ferrosilicon or silicon-barium alloy granules in step 3) ① and step 4) ⑤ is 3 to 8 mm.

[0034] In step 4) ⑥, the insulation material is carbonized rice husk, perlite or asbestos felt.

[0035] Compared with the existing technology, the beneficial effects of the present invention are:

[0036] 1. The working layer of the roller of the present invention is made of alloy cast iron, and the molten iron in the working layer is subjected to a modification process to obtain spherical or dot-shaped graphite. Graphite often exists in three free-state graphite forms in the metal matrix of the roller, namely flake, worm-shaped and spherical (or dot-shaped), and is a low-strength phase. Under the action of the rolling load of the roller, graphite easily falls off from the roller surface and forms small pits. When the rolled iron oxide scale is embedded in the pits, the surrounding metal matrix is ​​squeezed, torn and gradually forms microcracks, and the roller surface begins to become rough or microscopically peeled, which is a bad side of the existence of graphite. However, when graphite falls off the roller surface and covers and adheres to the surface of the roller, it can indirectly play the role of rolling lubrication, which is effective for smooth rolling. Comprehensively weighing the effects of graphite morphology on the cutting and invasion of metal matrix tissue, spherical or dot-shaped graphite has the weakest ability to cut the metal matrix tissue and the strongest ability to resist microcracks. The graphite morphology of the hot-rolled patterned steel plate roller matrix is ​​spherical or dot-shaped graphite, which maximizes the roller surface's resistance to microcracks.

[0037] 2. Using molten iron inoculation technology, the molten iron inoculation treatment of the roller working layer refines the grains and passivates the various carbides generated by the solidification of the molten iron in the roller working layer. While passivating the carbides in the metal matrix of the roller working layer, the strength and toughness of the roller body are continuously improved. The molten iron in the roller working layer must be inoculated after the deterioration treatment, otherwise the brittleness of the roller working layer will increase.

[0038] 3. Through heat treatment, the bainite morphology is controlled, ultimately achieving a lower bainite structure (acicular bainite) in the roll working layer. This also inhibits graphite growth in the metal matrix, achieving a graphite spheroidization level of 2-3 and a size level of 7-8. Bainite is a mechanical mixture of supersaturated ferrite and cementite. A microhardness of 324-645 HB is not only suitable for roll engraving, but also provides optimal matrix strength, toughness, and fatigue resistance. Bainite is further divided into lower bainite (acicular bainite) and upper bainite (feather bainite). Comparing the strength, toughness, and brittleness of the two structures, the lower bainite structure exhibits the best overall quality characteristics. Ultimately, the hardness of the working layer determines the quality characteristics of the roll, and the hardness is controlled between 60-80 HSD. This roll hardness is ideal for easy engraving, wear resistance, minimal change in roll profile thermal crown, and strong resistance to impact and thermal cracking. On the premise of keeping the surface quality of the hot-rolled patterned steel plate intact, the hot-rolled patterned steel plate can be smoothly rolled.

[0039] 4. The core layer of the roll of the present invention is made of high-strength ductile iron, which significantly reduces the production cost of the roll and improves the utilization rate of the roll working layer material. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] Figure 1 This is the matrix organization diagram of the patterned steel plate roller.

[0041] Figure 2 This is a graphite diagram of the matrix structure of the patterned steel plate roller.

[0042] Figure 3 This is a view of the roller surface of the patterned steel plate roller in Example 1 before it is put into the machine for the first time.

[0043] Figure 4 This is a view of the roller surface of the patterned steel plate roller in Example 1 during continuous secondary rolling. DETAILED DESCRIPTION

[0044] It should be noted that, unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the art to which this application belongs; the terms used herein in the specification of the application are for the purpose of describing specific embodiments only and are not intended to limit this application. Mentioning "embodiments" herein means that the specific features, structures or characteristics described in conjunction with the embodiments may be included in at least one embodiment of the present application. The appearance of this phrase in various places in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment that is mutually exclusive with other embodiments. It is explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments. Based on the embodiments in the present invention, all other embodiments obtained by those of ordinary skill in the art without making creative work are within the scope of protection of the present invention.

[0045] A method for manufacturing a hot-rolled patterned steel plate roller comprises the following steps:

[0046] 1) The roll body includes a working layer and a core layer. The working layer is made of acicular bainite ductile iron with the following chemical composition by mass fraction: C: 2.90-3.60; Si: 0.60-1.50; Mn: 0.40-1.20; P≤0.10; S≤0.05; Ni: 3.01-4.80; Cr: 1.0-3.0; Mo: 0.2-1.0; V+W+Nb<1.0; Mg+Re≥0.02;

[0047] The core material is ductile iron, with the following chemical composition by mass fraction: C: 2.50-3.30; Si: 2.0-3.0; Mn: 0.40-1.20; P≤0.05; S≤0.02; Ni≤1.5; Cr+Mo+V+W+Nb≤0.80; Mg+Re≥0.04;

[0048] 2) Molten iron smelting: The outer layer and core layer molten iron are smelted in the smelting furnace;

[0049] 3) Molten iron treatment:

[0050] ① The working layer molten iron tapping temperature is less than 1580℃. Before the working layer molten iron is tapped, a modified alloy material less than 0.8% of the working layer molten iron is pre-added to the bottom of the molten iron ladle and added to the working layer molten iron for modification treatment. When half of the working layer molten iron is tapped, ferrosilicon or silicon-barium alloy granules less than 1.0% of the working layer molten iron are added to the molten iron ladle to inoculate the alloy molten iron.

[0051] ② The core iron molten iron tapping temperature is less than 1500℃. Before the core iron molten iron is tapped, a spheroidizing agent less than 2.0% of the core iron molten iron is added to the bottom of the dam, and the upper part is covered with ferrosilicon or silicon-barium alloy blocks less than 2.0% of the core iron molten iron, and the core iron molten iron is added for spheroidizing treatment;

[0052] 4) Roller casting:

[0053] ① Start the centrifuge and ensure that the centrifugal gravity multiple of the inner surface of the centrifugal cooling mold reaches 40-150g;

[0054] ② Clean the slag from the working layer and pour molten iron into the roll working layer when the molten iron temperature reaches 1300-1420℃;

[0055] ③After the working layer molten iron is poured, immediately add protective slag from both ends of the cold mold. When the inner surface temperature of the molten iron in the working layer of the roll reaches 800-1180℃, reduce the speed and stop the centrifuge;

[0056] ④ Lift the cold mold and place it vertically above the base box, then buckle the riser box onto the cold mold;

[0057] ⑤ The core iron pouring temperature is controlled at 1320-1400℃. When the roll core is poured, ferrosilicon or silicon-barium alloy particles less than 5.0% of the core iron are added into the pouring hopper to perform instant inoculation treatment on the core iron.

[0058] ⑥After the roller core filling operation is completed, remove the pouring funnel and cover the upper part of the riser with insulation material;

[0059] ⑦The rollers are cooled naturally in the casting trench;

[0060] 5) Roll cooling and unpacking: unpack the rolls after cooling for more than 48 hours, and ensure that the roll body temperature is less than 100°C;

[0061] 6) Roller heat treatment:

[0062] ①Temperature rise <20℃ / h;

[0063] ②When the roller body temperature reaches 230-550℃, keep it warm for 10-30h;

[0064] ③ Cool down the kiln at a rate of less than 20°C / h. When the roller body temperature is less than 150°C, take the rolls out of the kiln and store them in a dry place.

[0065] The roll matrix structure is needle-shaped bainite structure, the graphite spheroidization level is 2 to 3 levels, the size level is controlled at 7 to 8 levels, and the graphite content is 3 to 5%.

[0066] Roller heat treatment is a critical control step in the manufacturing of this product. The temperature at which the roll body is held determines whether an upper or lower bainite structure is obtained, as well as the degree and size of graphite spheroidization.

[0067] In step 3) ②, the particle size of the ferrosilicon or silicon-barium alloy block material is 20 to 30 mm.

[0068] In step 3) ①, the modified alloy material is a silicon-calcium alloy, a silicon-zirconium alloy, a rare earth magnesium alloy or a pure magnesium alloy.

[0069] In step 3) ②, the spheroidizing agent is a rare earth magnesium alloy, a nickel magnesium alloy, or a yttrium-based heavy rare earth.

[0070] The particle size of the ferrosilicon or silicon-barium alloy granules in step 3) ① and step 4) ⑤ is 3 to 8 mm.

[0071] In step 4) ⑥, the insulation material is carbonized rice husk, perlite, or asbestos felt.

[0072] The technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments.

[0073] The chemical composition of the working layer of the roller body of the hot-rolled patterned steel plate is shown in Table 1;

[0074] Table 1: Chemical composition of working layer (%)

[0075]

[0076]

[0077] The chemical composition of the core layer of the hot-rolled patterned steel plate roller is shown in Table 2;

[0078] Table 2: Chemical composition of core layer (%)

[0079]

[0080] A method for manufacturing hot-rolled patterned steel plate rollers employs a centrifugal composite method. The method includes tooling preparation, molten iron smelting, molten iron modification, inoculation treatment, roller casting, cooling and unpacking, roller heat treatment and roller processing inspection, and roller application. The method includes the following specific steps:

[0081] 1) Tool preparation:

[0082] ①Bump the base, riser and end cover sand box, and control the sand thickness to 140-150mm. After the molding is completed, apply a 2-3mm layer of graphite coating on the inner surface of the sand mold and put it in the kiln for drying for 10 hours;

[0083] ② Use the pouring funnel to center the core filling and place it above the riser box;

[0084] ③ Place the base box stably in the casting trench, use a spirit level to align it horizontally, and use wedge iron to secure the base box;

[0085] ④ Assemble the impacted end cap flasks on both ends of the roller cold mold and place them in a kiln for preheating. The cold mold is preheated to 300-320℃ and kept warm for 3 hours before being removed from the kiln. Coating is then carried out in a centrifuge, with the coating thickness controlled at 2-5mm.

[0086] ⑤ Return the coated cold mold to the kiln for drying and place it on a centrifuge. Install the hot metal pouring system for the roller working layer. Position the hot metal outlet of the working layer hot metal pouring system at one-third of the total length of the cold mold from the casting end, with the hot metal flow aligned with the direction of cold mold rotation. Once all operations are complete, wait for hot metal pouring for the roller working layer.

[0087] 2) Molten iron smelting: The outer layer and core layer molten iron are smelted in the medium frequency furnace and industrial frequency furnace respectively.

[0088] 3) Molten iron treatment:

[0089] ① The working layer molten iron is discharged at a temperature of 1520°C. Before the working layer molten iron is discharged, a modified alloy material (silicon-calcium alloy) of less than 0.8% of the working layer molten iron is pre-added to the bottom of the molten iron ladle and added to the working layer molten iron for modification. When half of the working layer molten iron is discharged, 5-8mm ferrosilicon or silicon-barium alloy of less than 1.0% of the working layer molten iron is added to the ladle to inoculate the alloy molten iron.

[0090] ② The core layer molten iron is discharged from the furnace at a temperature of 1480°C. Before the core layer molten iron is discharged from the furnace, a rare earth magnesium alloy or nickel magnesium alloy spheroidizing agent less than 2.0% of the molten iron is added to the bottom of the dam, and the upper part is covered with 25-30mm ferrosilicon or silicon-barium alloy less than 2.0% of the core layer molten iron, and the core layer molten iron is added for spheroidizing treatment;

[0091] 4) Roller casting:

[0092] ① Start the centrifuge and ensure that the centrifugal gravity of the inner surface of the centrifugal cooling mold reaches 100g;

[0093] ② Clean the slag from the working layer and pour molten iron into the roller working layer when the molten iron temperature reaches 1400-1420℃;

[0094] ③After the working layer molten iron is poured, immediately add protective slag from both ends of the cold mold. When the inner surface temperature of the molten iron in the working layer of the roll reaches 1120℃, reduce the speed and stop the centrifuge;

[0095] ④ Lift the cold mold and place it vertically above the base box, then buckle the riser box onto the cold mold;

[0096] ⑤ The core iron pouring temperature is controlled at 1380-1400℃. When the roll core is filled, 3-5mm ferrosilicon or silicon-barium alloy particles are added along the flow direction to perform instant inoculation treatment on the core iron.

[0097] ⑥After the roller core filling operation is completed, remove the pouring funnel and cover the upper part of the riser with insulation material;

[0098] ⑦The rollers are cooled naturally in the casting trench;

[0099] 5) Roll cooling and unpacking: Unpack the rolls after cooling for 50 hours to ensure that the roll body temperature is less than 100℃.

[0100] 6) Roller heat treatment:

[0101] ①Temperature rise <20℃ / h;

[0102] ②When the roller body temperature reaches 520℃, keep it warm for 20 hours;

[0103] ③ Cool down the kiln at a rate of less than 20°C / h. When the roller body temperature is less than 150°C, take the rolls out of the kiln and store them in a dry place.

[0104] 7) Roller processing inspection:

[0105] ①The hardness difference of the same generatrix of the roller body can be controlled within ±1HSD;

[0106] ②The hardness difference of the roller surface in the circumferential direction can be controlled within ±0.5HSD;

[0107] ③10mm deep roller surface hardness drop <0.8HSD.

[0108] The roller body matrix is ​​acicular bainite (see attached Figure 1 ); 3-5% dot graphite is distributed in the metal matrix (see attached Figure 2 ).

[0109] Roller hardness test, see Table 3;

[0110] Table 3: Roller hardness test

[0111]

[0112]

[0113] The tensile strength of the roll and the roll body matrix structure test are shown in Table 4;

[0114] Table 4: Roll tensile strength and roll body matrix structure test

[0115]

[0116] The above table classifies graphite according to GB / T9941-2009 standard.

[0117] The working layer material of the roller of the present invention adopts needle-shaped bainite ductile iron, which is different from chilled cast iron material and infinite chilled cast iron material: the needle-shaped bainite ductile iron has better crack resistance, high comprehensive performance and moderate hardness, and is particularly suitable for engraved rollers; the core layer material of the roller adopts high-strength ductile iron material, the roller shaft has high strength and strong resistance to bending and breaking.

[0118] The rollers of Examples 1 to 3 were used continuously on the machine, and no local cracking occurred on the roller surface; the petals remained in good condition and the edges were intact (see attached Figure 3 and attached Figure 4 ).

[0119] Although embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and variations may be made to these embodiments without departing from the principles and basic spirit of the invention, and the scope of the invention is defined by the appended claims and their equivalents.

Claims

1. A method for manufacturing a hot-rolled patterned steel plate roller, characterized in that: The following steps are involved: 1) The roller body includes a working layer and a core layer. The working layer is made of acicular bainite ductile iron with the following chemical composition by mass fraction: C: 2.90-3.60; Si: 0.60-1.50; Mn: 0.40-1.20; P≤0.10; S≤0.05; Ni: 3.01~4.80; Cr: 1.0~3.0; Mo: 0.2-1.0; V+W+Nb<1.0; Mg+Re≥0.02; The core material is ductile iron, with the following chemical composition by mass fraction: C: 2.50-3.30; Si: 2.0-3.0; Mn: 0.40-1.20; P≤0.05; S≤0.02; Ni≤1.5; Cr+Mo+V+W+Nb≤0.80; Mg+Re≥0.04; 2) Molten iron smelting: The outer layer and core layer molten iron are smelted in the smelting furnace; 3) Molten iron treatment: ① Before the working layer molten iron is discharged from the furnace, a modified alloy material of less than 0.8% of the working layer molten iron is pre-added to the bottom of the molten iron ladle and added to the working layer molten iron for modification treatment; when the working layer molten iron is half discharged from the furnace, ferrosilicon or silicon-barium alloy granules of less than 1.0% of the working layer molten iron are added to the molten iron ladle to inoculate the alloy molten iron; ② Before the core layer molten iron is discharged from the furnace, a spheroidizing agent of less than 2.0% of the core layer molten iron is added to the bottom of the dam, and the upper part is covered with ferrosilicon or silicon-barium alloy blocks of less than 2.0% of the core layer molten iron, and the core layer molten iron is added for spheroidizing treatment; 4) Roller casting: ① Start the centrifuge, and the centrifugal gravity of the inner surface of the centrifugal cooling type reaches 40-150g; ② Clean the slag from the working layer and pour molten iron into the roll working layer when the molten iron temperature reaches 1300-1420℃; ③After the working layer molten iron is poured, immediately add protective slag from both ends of the cold mold. When the inner surface temperature of the molten iron in the working layer of the roll reaches 800-1180℃, reduce the speed and stop the centrifuge; ④ Lift the cold mold and place it vertically above the base box, then buckle the riser box onto the cold mold; ⑤ The core iron pouring temperature is controlled at 1320-1400℃. When the roll core is poured, ferrosilicon or silicon-barium alloy particles less than 5.0% of the core iron are added into the pouring hopper to perform instant inoculation treatment on the core iron. ⑥After the roller core filling operation is completed, remove the pouring funnel and cover the upper part of the riser with insulation material; ⑦The rollers are cooled naturally in the casting trench; 5) Roll cooling and unpacking: unpack the rolls after cooling for more than 48 hours, and ensure that the roll body temperature is less than 100°C; 6) Roller heat treatment: ①Temperature rise <20℃ / h; ②When the roller body temperature reaches 230-550℃, keep it warm for 10-30h; ③ Cool down the kiln at a rate of less than 20°C / h. When the roller body temperature is less than 150°C, take the rolls out of the kiln and store them in a dry place.

2. The method for manufacturing a hot-rolled patterned steel plate roller according to claim 1, characterized in that: In step 3), the temperature of the molten iron in the working layer is less than 1580°C; the temperature of the molten iron in the core layer is less than 1500°C.

3. The method for manufacturing a hot-rolled patterned steel plate roller according to claim 1, characterized in that: In step 3) ②, the particle size of the ferrosilicon or silicon-barium alloy block material is 20 to 30 mm.

4. The method for manufacturing a hot-rolled patterned steel plate roller according to claim 1, characterized in that: In step 3) ①, the modified alloy material is a silicon-calcium alloy, a silicon-zirconium alloy, a rare earth magnesium alloy or a pure magnesium alloy.

5. The method for manufacturing a hot-rolled patterned steel plate roller according to claim 1, characterized in that: In step 3) ②, the spheroidizing agent is a rare earth magnesium alloy, a nickel magnesium alloy or a yttrium-based heavy rare earth.

6. The method for manufacturing a hot-rolled patterned steel plate roller according to claim 1, characterized in that: The particle size of the ferrosilicon or silicon-barium alloy granules in step 3) ① and step 4) ⑤ is 3 to 8 mm.

7. The method for manufacturing a hot-rolled patterned steel plate roller according to claim 1, characterized in that: In step 4) ⑥, the insulation material is carbonized rice husk, perlite or asbestos felt.

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