Forged steel straightening roll structure and production process

Abstract

The invention discloses a forged steel straightening roll structure and a production process, and relates to the technical field of straightening rolls. The forged steel straightening roll structure comprises a roll sleeve and a roll shaft, and the roll sleeve is located on the outer side of the roll shaft. The middle sleeve is mounted on the outer side of the roller shaft; a connecting thread groove is formed in the outer side of the middle sleeve; a U-shaped groove is formed in one end of the roller shaft, and an inlet connector and a return connector are arranged in the U-shaped groove and connected with a pipeline; round chamfers are arranged at the two ends of the surface of the roller sleeve, and composite coatings are installed in the round chamfers. The composite coating comprises a grain bottom layer, a first coating and a second coating, the grain bottom layer is obliquely distributed, and the first coating is arranged on the upper portion of the grain bottom layer in a laser cladding mode. The coating II is arranged on the outer side of the coating I in a laser cladding manner; the contents of W, Co, Cr and Ni in the second coating are optimized, Ti is added, and the technical problems that the abrasion resistance and the high-temperature tensile strength of the straightening roll are insufficient are solved in the aspect of performance through accurate blending.

Description

Technical Field

[0001] The invention belongs to the technical field of straightening rollers, and in particular relates to a forged steel straightening roller structure and a production process. Background Art

[0002] Straightening machine is a device for straightening metal profiles, bars, pipes, wires, etc. Straightening machine squeezes bars and other materials through straightening rollers to change their straightness. There are generally two rows of straightening rollers, with varying numbers. It can be used in the hot rolling smelting industry. The working temperature of hot rolling straightening rollers is generally in the range of 500-700℃. It is necessary not only to ensure the dimensional accuracy and shape requirements of the steel profiles, but also to ensure the surface quality of the steel profiles. Surface defects such as roller marks and scratches should not appear. It is necessary to improve the operation rate of the straightening machine, reduce frequent roller changes, and avoid uneven wear and damage to the roller surface. Therefore, it is necessary to improve the wear resistance, scratch resistance and deformation resistance of the straightening rollers to ensure their service life and performance.

[0003] The surface of the straightening roller is usually processed into a certain hole shape. When straightening steel, the hole surface is in direct contact with the steel. Under the action of temperature and pressure, it is mainly subjected to bending fatigue and severe wear during operation. Therefore, the straightening roller is required to have high surface hardness, sufficient rigidity and high fatigue strength, and no cracking or oxidation will occur under the action of repeated thermal stress.

[0004] At present, straightening rollers are mostly made of alloys and cold-hardened alloy cast irons with high nickel, chromium and molybdenum content. Among them, alloy straightening rollers are mostly produced by forging or casting methods. The straightening rollers produced have high toughness, but relatively insufficient wear resistance, which increases the replacement frequency of the straightening rollers. In addition, in the hot rolling industry, the surface temperature is continuously high, which puts a great test on the straightening roller material, resulting in the problem that the service life is difficult to meet the test standards.

[0005] Therefore, in order to solve the above problems, a forged steel straightening roller structure and production process are proposed. Summary of the invention

[0006] The object of the present invention is to provide a forged steel straightening roller structure and a production process to solve the technical problems of the straightening roller proposed in the above background technology, namely, insufficient wear resistance and high temperature tensile strength and lack of effective cooling method.

[0007] To achieve the above object, the present invention provides the following technical solutions:

[0008] The forged steel straightening roller structure comprises a roller sleeve and a roller shaft, wherein the roller sleeve is located on the outside of the roller shaft; and further comprises a central sleeve, wherein the central sleeve is installed on the outside of the roller shaft, and both ends of the central sleeve are chamfered; a connecting groove is arranged on the outside of the central sleeve, and the connecting groove is connected to the inner side of the roller sleeve;

[0009] A U-shaped groove is provided at one end of the roller shaft, an inlet port and a return port are provided in the U-shaped groove, and a pipeline is connected; the outside of the pipeline is connected to a cooling device;

[0010] A bearing seat is installed on the outer side of the roller sleeve, and a spherical roller bearing is installed inside the bearing seat. The inner ring of the spherical roller bearing is connected to the roller shaft, and the outer ring is connected to the inner side of the bearing seat.

[0011] Round chamfers are arranged at both ends of the surface of the roller sleeve, and a composite coating is installed inside the rounded corners;

[0012] The composite coating comprises a texture bottom layer, a coating one and a coating two, wherein the texture bottom layer is inclinedly distributed, the upper part of the texture bottom layer is laser-clad with the coating one; the coating two is laser-clad on the outer side of the coating one;

[0013] The coating comprises components by weight:

[0014] 10-15 parts of Ni, 5.0-8.0 parts of Cr, 10-14 parts of Co, 3.2-4.6 parts of B, 3.0-4.2 parts of Si, 4.0-6.5 parts of W, 0.5-0.8 parts of C, 1.0-2.3 parts of Mo, the balance is Fe and trace impurities, among which: 0.17≤(Co+B) / (Fe+Ni+Cr)≤0.26, 0.11≤(Si+Cr) / (Ni+Fe)≤0.20;

[0015] The combined ratio of Co and B is optimized, which is easy to form a hard compound with Ni / Cr materials, resulting in grain refinement; of course, too large a ratio will lead to brittleness and difficulty in processing, so the ratio needs to be adjusted. Further, Cr and Si are both oxygen-absorbing elements, which will reduce the ratio of nickel oxide, reduce pores, and ensure the strength and hardness of the alloy.

[0016] The coating 2 includes components by weight:

[0017] 3.0-4.0 parts of Fe, 8-15 parts of Cr, 2.0-3.0 parts of B, 2.0-3.0 parts of Si, 2.2-4.5 parts of C, 24-29 parts of W, 3.0-4.0 parts of Ti, 0.1-0.2 parts of P, 1.0-2.0 parts of Co, the balance is Ni and trace impurities, 0.049≤(B+Co) / (Ni+Cr)≤0.095, 0.20≤(Co+W) / 2(N i+Cr+C)≤0.27.

[0018] The second alloy coating of the present application is a nickel-chromium alloy, which makes the coating surface have higher hardness, wear resistance and heat corrosion resistance. The higher content of Ni improves the stability of the face-centered cubic γ phase of the matrix and improves the tendency of the heat-resistant alloy to precipitate various harmful phases, so that it can improve the strength of the alloy while maintaining good plasticity and toughness.

[0019] Nickel has high corrosion resistance to acids and alkalis, and has rust and heat resistance at high temperatures, so it can be used as a surface coating in contact with hot-rolled workpieces. The heat-resistant alloy adds the solid solution element Cr, so that the heat-resistant alloy has a multi-element solid solution strengthening effect, which increases the use temperature of the slider; the addition of Co ensures the high-temperature creep strength of the heat-resistant alloy; Si melts in the alloy matrix and its solid solution strengthening effect, Co has excellent corrosion resistance, heat resistance and oxidation resistance and other valuable characteristics; B and Co are combined to form hard metal compounds with Ni and or Cr in the matrix, so that they are dispersed in the alloy to play a role in dispersion strengthening. After ensuring the precise addition of Co content, B will also be combined to promote the precipitation of dispersed chromium-carbon, boron-chromium hard phase, plastic face-centered cubic structure solid solution and promote the formation of carbides at high temperatures. After comprehensive configuration, the hard alloy can improve its hardness and wear resistance, ensure excellent bonding strength, and still have high hardness and good oxidation resistance, impact resistance, thermal shock resistance and corrosion resistance at high temperatures.

[0020] Adding a higher proportion of W can significantly improve the red hardness and heat strength, and optimize the hardness and strength of the metal compound coating; a tungsten-cobalt-carbon compound phase will be formed inside the coating, and it will cooperate with B and Co to form a hard metal compound with Ni and / or Cr in the matrix, so that it is dispersed in the alloy and plays a role in dispersion strengthening. Adding P can refine the crystal particle size, enhance its strength and wear resistance, and control the P content to avoid affecting the high-temperature durability of the heat-resistant alloy.

[0021] The addition of an appropriate amount of Si helps to increase the fluidity of the heat-resistant alloy and acts as a deoxidizer, reducing the formation of nickel oxide by nickel elements at high temperatures and oxygen elements, and easily generating pores during crystallization, so as to avoid a large number of residual pores, which may cause the connection parts to fall off easily; wherein, Si, Ti, and Cr are all oxygen-absorbing elements, and Si is easy to generate compounds such as silicates, which affect the performance of the alloy; Ti is easy to absorb oxygen and hydrogen during the alloy preparation process, and forms an oxide layer. The grains in the high-temperature alloy are easy to grow under high temperature conditions, resulting in unstable grain boundaries, easy formation of pores and cracks, and thus reducing the mechanical properties of the material. The addition of titanium can combine with impurity elements at the grain boundaries to form stable compounds, thereby inhibiting the growth of grains and stabilizing the grain boundary structure. The stability of this microstructure helps to improve the mechanical properties and heat resistance of the alloy. Cr can also react with oxygen in the alloy to form an oxide protective film, thereby enhancing the corrosion resistance of the alloy. In actual operation, it is possible to consider reducing the oxygen content by introducing nitrogen. Therefore, it is necessary to control the proportion of oxygen-absorbing elements in heat-resistant alloys. Too high a content will lead to a decrease in performance. For example, Si exceeding 4% will increase brittleness.

[0022] The difference between the first coating and the second coating is that a larger proportion of C is added, which is easy to form skeleton-like carbides and eutectic carbides with W, and has a positive effect on improving the high-temperature strength of the heat-resistant alloy.

[0023] For coating 1, it is an iron-based alloy; it has certain applications in wear resistance, corrosion resistance and high temperature resistance, but its high temperature performance is slightly inferior to that of nickel-based alloys, but it can be used as a good intermediate phase, as a carrier connecting the bottom layer of the grain and coating 2, and the cost is lower; among them, B and Co form hard metal compounds with Ni and / or Cr in the matrix, so that they are dispersed in the alloy to play a role in dispersion strengthening; Si and Cr are easy to form oxides, reducing the proportion of Ni combined into oxides; Mo can refine the grains of steel, improve hardenability and thermal strength, and maintain sufficient strength and creep resistance at high temperatures. Adding molybdenum to structural steel can improve mechanical properties. It can also suppress the brittleness of alloy steel caused by fire.

[0024] The texture bottom layer is connected to the laser cladding coating at an oblique angle, which can enhance the contact during cladding, make the composite coating have better bonding ability, and reduce the probability of coating falling off due to high temperature.

[0025] In a further technical solution, end covers are respectively installed at both ends of the bearing seat, and the roller shaft passes through the end covers; the roller shaft is a stepped shaft, a large diameter portion is provided in the middle of the roller shaft, an installation groove is opened on the inner side of the center sleeve, and the installation groove is connected to the large diameter portion.

[0026] In a further technical solution, the connecting groove includes an oblique angle portion and surface notches, and the surface notches are provided in multiple groups and are arranged in parallel in the same direction; the oblique angle portion is in a "W" shape.

[0027] In a further technical solution, it also includes a mounting base plate, which is connected to the two sets of bearing seats and is located at the bottom of the roller sleeve;

[0028] The central sleeve includes a spiral tube, and the spiral tube is wound inside the central sleeve; a return diameter portion is provided in the middle of the roller shaft, and a return port is connected through the return diameter portion;

[0029] The roller shaft is provided with a guide groove, which is connected to the return diameter portion; and the guide groove is provided with a connecting port; a fixing block is provided in the middle sleeve and is connected to a clamping column; the clamping column is connected to the fixing block, and a fixing cavity is provided in the fixing block, and the fixing cavity is connected to the spiral tube.

[0030] In a further technical solution, a notch is provided at the bottom of the clamping column, and an abutting bent rod is provided in the guide groove. The rod body of the abutting bent rod is rotatably connected to the guide groove, and a convex ball is installed on the top, and the convex ball is adapted to the notch; a horizontal portion is provided at the bottom of the abutting bent rod, and the horizontal portion abuts against the bottom of the clamping column. The cooling pipe arranged inside the roller shaft can be distributed in a spiral shape in the middle sleeve. When the middle sleeve is welded to the roller shaft, the middle sleeve is a two-petal type. The clamping column is clamped to the abutting bent rod in the guide groove by alignment, so that the convex ball of the abutting bent rod is clamped in the notch to complete the closed installation, so that it presents a relatively closed installation structure. A U-shaped groove is provided on the roller shaft, and its diameter can be used for manual installation of the corresponding connecting pipe.

[0031] A production process for a forged steel straightening roller structure comprises the following steps:

[0032] Step 1: Material preparation and pretreatment: After the raw materials of the roller sleeve are prepared, they are cleaned and rust-removed;

[0033] Step 2: smelting in an electric furnace, heating the raw materials of the roller sleeve at high temperature, melting them and putting them into a mold to form an ingot into a block;

[0034] Step 3: Forging. Take out the block-shaped roller sleeve, forge and adjust the position, and forge it into a columnar structure. If the temperature drops too much, it needs to be returned to the furnace for heating.

[0035] Step 4, a guide pin is driven into the middle of the forged roller sleeve so that the middle of the roller sleeve has a center hole to form a sleeve shape;

[0036] Step 5, install the prefabricated column in the center hole, with one end of the prefabricated column being chamfered and the other end extending outside the roller sleeve, and continue forging;

[0037] Step 6, take out the prefabricated column, prepare the forming roller shaft in advance, and connect the roller shaft with the middle sleeve on the surface of the roller shaft; install the roller shaft and the middle sleeve into the roller sleeve, and the chamfer of one end of the middle sleeve abuts against the chamfer in the center hole; the horizontal distance difference A between the other end and the edge line of the center hole of the corresponding side, install the pressing die on the outer side of the roller sleeve of A, and adjust the spacing of the pressing die so that the diameter of the roller sleeve after pressing is larger than the designed required diameter; after the installation is completed, continue to forge until forming; the workpiece is air-cooled after forging;

[0038] Step 7, pre-heat treatment, normalizing the workpiece to 875-930℃ for 2h; post-spheroidizing annealing, 640-750℃ for 3-5h;

[0039] Step 8, perform ultrasonic flaw detection on the workpiece; then perform rough machining on the roller sleeve surface and both side ends of the roller shaft;

[0040] Step 9, modulated heat treatment, quenching the rough-machined workpiece, oil quenching at 950-1050°C for 0.5h; post-tempering at 640-680°C for 1h;

[0041] Step 10: semi-finishing, finishing the size; marking the bottom layer of the pattern on the surface of the roller sleeve, with the pitch of the inclined path being 2-5 mm;

[0042] Step 11, laser coating coating 1, and the coating line is running around the roller surface; after coating, coating 1 is air-cooled and the surface is polished; the powder of coating 1 includes 10-15 parts of Ni, 5.0-8.0 parts of Cr, 10-14 parts of Co, 3.2-4.6 parts of B, 3.0-4.2 parts of Si, 4.0-6.5 parts of W, 0.5-0.8 parts of C, 1.0-2.3 parts of Mo, and the balance is Fe and trace impurities, wherein: 0.17≤(Co+B) / (Fe+Ni+Cr)≤0.26, 0.11≤(Si+Cr) / (Ni+Fe)≤0.20;

[0043] Step 12, laser coating the second coating, and the coating line is walking around the roller surface; after the second coating is completed, air-cooling and surface grinding; the powder of the first coating is 3.0-4.0 parts of Fe, 8-15 parts of Cr, 2.0-3.0 parts of B, 2.0-3.0 parts of Si, 2.2-4.5 parts of C, 24-29 parts of W, 3.0-4.0 parts of Ti, 0.1-0.2 parts of P, 1.0-2.0 parts of Co, the balance is Ni and trace impurities, 0.049≤(B+Co) / (Ni+Cr)≤0.095, 0.20≤(Co+W) / 2(Ni+Cr+C)≤0.27;

[0044] Step 13, after spraying, remelting treatment, the remelting temperature is 1000 ~ 1200 ℃; static and dynamic balancing treatment;

[0045] Step 14, in step 6, a U-shaped groove is pre-opened on one end of the roller shaft, and corresponding pipes of the inlet and return ports are installed;

[0046] Finally, the corresponding bearing seat, end cover and installation floor are installed to obtain the finished product.

[0047] In a further technical solution, in step 10, the texture bottom layer is tilted and divided into non-working areas on both sides, and the texture bottom layer is engraved on the curved surface in the non-working area; and the direction of coating 1 is at an angle of 2-3° with the texture bottom layer.

[0048] In a further technical solution, in step 13, secondary quenching and tempering and recrystallization treatment can be carried out, the quenching temperature is controlled at 800-950°C for 0.5h; tempering is 200-280°C for 1h; the straightening rollers after quenching and tempering are air-cooled to room temperature.

[0049] Beneficial Effects

[0050] The second alloy coating of the present application is a nickel-chromium alloy, so that the coating surface has high hardness, wear resistance, and heat corrosion resistance. The high content of Ni improves the stability of the matrix face-centered cubic γ phase and improves the tendency of the heat-resistant alloy to precipitate various harmful phases, so that it can improve the strength of the alloy while maintaining good plasticity and toughness. B and Co are combined to form hard metal compounds with Ni and or Cr in the matrix, so that the dispersed distribution in the alloy plays a role in dispersion strengthening. After ensuring the precise addition of Co content, B is also combined to promote the precipitation of dispersed chromium-carbon, boron-chromium hard phase, plastic face-centered cubic structure solid solution, and promote the formation of carbides at high temperatures. After comprehensive configuration, the hardness and wear resistance of the cemented carbide can be improved, and excellent bonding strength can be ensured. At the same time, it still has high hardness and good oxidation resistance, impact resistance, thermal shock resistance and corrosion resistance at high temperatures.

[0051] Adding a higher proportion of W can significantly improve the red hardness and thermal strength, and optimize the hardness and strength of the metal compound coating; a tungsten-cobalt-carbon compound phase will be formed inside the coating, and it will cooperate with B and Co to form a hard metal compound with Ni and / or Cr in the matrix, making it dispersed in the alloy and play a role of dispersion strengthening.

[0052] The texture bottom layer is connected to the laser cladding coating at an oblique angle, which can enhance the contact during cladding, make the composite coating have better bonding ability, and reduce the probability of coating falling off due to high temperature. BRIEF DESCRIPTION OF THE DRAWINGS

[0053] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, for ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0054] Figure 1 is a cross-sectional view of a forged steel straightening roll of the present invention;

[0055] Figure 2 for Figure 1 A magnified view of part B;

[0056] Figure 3 for Figure 1 Enlarged view of part C

[0057] Figure 4 It is a cross-sectional view of the roller shaft and the middle sleeve of the present invention at the guide groove;

[0058] Figure 5 for Figure 4 A magnified view of the D portion;

[0059] Figure 6 It is a schematic diagram of the bottom layer of the outer texture of the roller sleeve of the present invention;

[0060] Figure 7 It is a partial structural schematic diagram of the production method in the present invention;

[0061] In the figure: 1. roller sleeve; 2. roller shaft; 3. center sleeve; 4. U-shaped groove; 5. pipeline; 6. bearing seat; 7. spherical roller bearing; 8. texture bottom layer; 9. coating one; 10. coating two; 11. end cover; 12. bevel portion; 13. surface notch; 14. mounting base plate; 15. spiral tube; 16. fixing block; 17. clamping column; 18. guide column; 19. prefabricated column; 20. pressing die; 21. large diameter portion; 22. return diameter portion; 23. guide groove; 24. abutting bent rod; 241. horizontal portion; 171. notch portion; 25. convex ball. DETAILED DESCRIPTION

[0062] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0063] The application principle of the present invention is further described below in conjunction with the accompanying drawings and specific embodiments.

[0064] Example 1

[0065] See also Figure 1-7As shown, an embodiment of the present invention is provided, which provides a forged steel straightening roller structure, including a roller sleeve 1 and a roller shaft 2, wherein the roller sleeve 1 is located on the outside of the roller shaft 2; and further comprising a center sleeve 3, wherein the center sleeve 3 is installed on the outside of the roller shaft 2, and both ends of the center sleeve 3 are chamfered; a connecting groove is provided on the outside of the center sleeve 3, and the connecting groove is connected to the inner side of the roller sleeve 1;

[0066] A U-shaped groove 4 is formed at one end of the roller shaft 2. An inlet port and a return port are provided in the U-shaped groove 4 and connected to a pipeline 5. The pipeline 5 is externally connected to a cooling device.

[0067] A bearing seat 6 is installed on the outer side of the roller sleeve 1, and a spherical roller bearing 7 is installed inside the bearing seat 6. The inner ring of the spherical roller bearing 7 is connected to the roller shaft 2, and the outer ring is connected to the inner side of the bearing seat 6. A positioning hole is opened on the outer side of the roller sleeve, and a flange is installed on the roller sleeve and is detachably connected to the roller sleeve by bolts.

[0068] Round chamfers are provided at both ends of the surface of the roller sleeve 1, and a composite coating is installed inside the rounded corners;

[0069] like Figure 2 As shown, the composite coating includes a texture bottom layer 8, a coating layer 1 9 and a coating layer 2 10. The texture bottom layer 8 is inclinedly distributed, and the upper part of the texture bottom layer 8 is laser-clad with a coating layer 1 9; and the coating layer 2 10 is laser-clad on the outer side of the coating layer 1 9;

[0070] The coating 9 comprises the following components by weight:

[0071] 10-15 parts of Ni, 5.0-8.0 parts of Cr, 10-14 parts of Co, 3.2-4.6 parts of B, 3.0-4.2 parts of Si, 4.0-6.5 parts of W, 0.5-0.8 parts of C, 1.0-2.3 parts of Mo, the balance is Fe and trace impurities, among which: 0.17≤(Co+B) / (Fe+Ni+Cr)≤0.26, 0.11≤(Si+Cr) / (Ni+Fe)≤0.20;

[0072] The coating 210 comprises components by weight:

[0073] 3.0-4.0 parts of Fe, 8-15 parts of Cr, 2.0-3.0 parts of B, 2.0-3.0 parts of Si, 2.2-4.5 parts of C, 24-29 parts of W, 3.0-4.0 parts of Ti, 0.1-0.2 parts of P, 1.0-2.0 parts of Co, the balance is Ni and trace impurities, 0.049≤(B+Co) / (N i+Cr)≤0.095, 0.20≤(Co+W) / 2(N i+Cr+C)≤0.27.

[0074] In a further technical solution, end covers 11 are respectively installed at both ends of the bearing seat 6, and the roller shaft 2 passes through the end covers 11; the roller shaft 2 is a stepped shaft, and a large diameter portion 21 is provided in the middle of the roller shaft 2, and an installation groove is opened on the inner side of the center sleeve 3, and the installation groove is connected to the large diameter portion 21.

[0075] like Figure 3 As shown, the connecting groove includes an oblique angle portion 12 and surface notches 13. The surface notches 13 are provided in multiple groups and are arranged in parallel in the same direction. The oblique angle portion 12 is in a "W" shape.

[0076] The corresponding inclined roller straightening machine needs to be installed in the straightening machine. It also includes a mounting base plate 14, which is connected to the two sets of bearing seats 6 and is located at the bottom of the roller sleeve 1;

[0077] The middle sleeve 3 includes a spiral tube 15, and the spiral tube 15 is wound inside the middle sleeve 3; a return diameter portion 22 is provided in the middle of the roller shaft 2, and a return port is connected through the return diameter portion 22;

[0078] like Figure 4 As shown, a guide groove 23 is provided on the roller shaft 2, and the guide groove 23 is connected to the return diameter portion 22; and a connecting port is provided on the guide groove 23; a fixing block 16 is provided in the middle sleeve 3, and is connected to a clamping column 17; the clamping column 17 is connected to the fixing block 16, and a fixing cavity is provided in the fixing block 16, and the fixing cavity is connected to the spiral tube 15.

[0079] like Figure 5 As shown, a notch 171 is provided at the bottom of the clamping column 17, and an abutting bent rod 24 is provided in the guide groove 23. The rod body of the abutting bent rod 24 is rotatably connected to the guide groove 23, and a convex ball 25 is installed on the top, and the convex ball 25 is adapted to the notch 171;

[0080] A horizontal portion 241 is disposed at the bottom of the abutting bent rod 24 , and the horizontal portion 241 abuts against the bottom of the clamping column 17 .

[0081] A production process for a forged steel straightening roller structure comprises the following steps:

[0082] Step 1, material preparation and pretreatment, after the raw materials of the roller sleeve 1 are prepared, they are cleaned and rust-removed;

[0083] Step 2, smelting in an electric furnace, heating the raw materials of the roller sleeve 1 at high temperature, putting them into a mold for ingot casting after melting to form a block;

[0084] Step 3, forging, taking out the block-shaped roller sleeve 1, forging and adjusting the position, forging into a columnar structure; if the temperature drops too much, it needs to be returned to the furnace for heating;

[0085] Step 4, a guide pin 18 is driven into the middle of the forged roller sleeve 1 so that the middle of the roller sleeve 1 has a center hole to form a sleeve shape;

[0086] Step 5, installing the prefabricated column 19 in the center hole, with one end of the prefabricated column 19 being chamfered and the other end extending outside the roller sleeve 1, and continuing forging;

[0087] Step 6, take out the prefabricated column 19, prepare the forming roller shaft 2 in advance, and connect the intermediate sleeve 3 on the surface of the roller shaft 2; install the roller shaft 2 and the intermediate sleeve 3 into the roller sleeve 1, and the chamfer of one end of the intermediate sleeve 3 abuts against the chamfer in the center hole; the horizontal distance difference A between the other end and the edge line of the center hole of the corresponding side, install the pressing die 20 on the outer side of the roller sleeve 1 of A, and adjust the spacing of the pressing die 20 so that the diameter of the roller sleeve 1 after pressing is larger than the designed required diameter; after the installation is completed, continue to forge until forming; the workpiece is air-cooled after forging;

[0088] Step 7, pre-heat treatment, normalizing the workpiece to 875-930℃ for 2h; post-spheroidizing annealing, 640-750℃ for 3-5h;

[0089] Step 8, perform ultrasonic flaw detection on the workpiece; then perform rough machining on the surface of the roller sleeve 1 and the ends of both sides of the roller shaft 2;

[0090] Step 9, modulated heat treatment, quenching the rough-machined workpiece, oil quenching at 950-1050°C for 0.5h; post-tempering at 640-680°C for 1h;

[0091] Step 10: semi-finishing, finishing the size; and marking the bottom layer 8 of the pattern on the surface of the roller sleeve 1, with the pitch of the inclined path being 2-5 mm;

[0092] Step 11, laser coating a coating 9, and the coating line is running around the roller surface; after coating, the coating 9 is air-cooled and the surface is polished; the powder of the coating 9 includes 10 to 15 parts of Ni, 5.0 to 8.0 parts of Cr, 10 to 14 parts of Co, 3.2 to 4.6 parts of B, 3.0 to 4.2 parts of Si, 4.0 to 6.5 parts of W, 0.5 to 0.8 parts of C, 1.0 to 2.3 parts of Mo, and the balance is Fe and trace impurities, wherein: 0.17≤(Co+B) / (Fe+Ni+Cr)≤0.26, 0.11≤(Si+Cr) / (Ni+Fe)≤0.20;

[0093] Step 12, laser coating the second coating 10, and the coating line is walking around the roller surface; after the coating of the second coating 10 is completed, it is air-cooled and the surface is polished; the powder of the second coating is 3.0-4.0 parts of Fe, 8-15 parts of Cr, 2.0-3.0 parts of B, 2.0-3.0 parts of Si, 2.2-4.5 parts of C, 24-29 parts of W, 3.0-4.0 parts of Ti, 0.1-0.2 parts of P, 1.0-2.0 parts of Co, and the balance is Ni and trace impurities, 0.049≤(B+Co) / (Ni+Cr)≤0.095, 0.20≤(Co+W) / 2(Ni+Cr+C)≤0.27;

[0094] Step 13, after spraying, remelting treatment, the remelting temperature is 1000 ~ 1200 ℃; static and dynamic balancing treatment;

[0095] Step 14, in step 6, a U-shaped groove 4 is pre-opened on one end of the roller shaft 2, and corresponding pipes 5 of the inlet and return ports are installed;

[0096] Then, the corresponding bearing seat 6, end cover 11 and installation floor are installed to obtain the finished product.

[0097] In step 10, the texture bottom layer 8 is tilted and divided into non-working areas 30 on both sides, and the texture bottom layer 8 is marked on the curved surface in the non-working area 30; and the direction of the coating 9 and the texture bottom layer 8 are at an angle of 2-3°.

[0098] In step 13, secondary quenching and tempering and recrystallization treatment can be performed, with the quenching temperature controlled at 800-950°C for 0.5h; tempering at 200-280°C for 1h; and air cooling the straightening rollers after quenching and tempering to room temperature.

[0099] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above and that the present invention can be implemented in other specific forms without departing from the spirit or essential features of the present invention. Therefore, the embodiments should be considered exemplary and non-restrictive in all respects, and the scope of the present invention is defined by the appended claims rather than the above description, and it is intended that all changes falling within the meaning and scope of the equivalent elements of the claims be included in the present invention.

[0100] In addition, it should be understood that although the present specification is described according to implementation modes, not every implementation mode contains only one independent technical solution. This description of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment may also be appropriately combined to form other implementation modes that can be understood by those skilled in the art.

Claims

1. A forged steel straightening roller structure, comprising a roller sleeve (1) and a roller shaft (2), wherein the roller sleeve (1) is located outside the roller shaft (2); characterized in that: It also includes a central sleeve (3), which is installed on the outside of the roller shaft (2), and both ends of the central sleeve (3) are chamfered; the outer side of the central sleeve (3) is provided with a connecting groove, and the connecting groove is connected to the inner side of the roller sleeve (1); A U-shaped groove (4) is provided at one end of the roller shaft (2), an inlet port and a return port are provided in the U-shaped groove (4), and are connected to a pipeline (5); the pipeline (5) is externally connected to a cooling device; A bearing seat (6) is installed on the outer side of the roller sleeve (1), and a spherical roller bearing (7) is installed inside the bearing seat (6), the inner ring of the spherical roller bearing (7) is connected to the roller shaft (2), and the outer ring is connected to the inner side of the bearing seat (6); Round chamfers are arranged at both ends of the surface of the roller sleeve (1), and a composite coating is installed inside the rounded corners; The composite coating comprises a texture bottom layer (8), a coating layer 1 (9) and a coating layer 2 (10); the texture bottom layer (8) is inclinedly distributed, and the upper part of the texture bottom layer (8) is laser-clad with the coating layer 1 (9); and the coating layer 2 (10) is laser-clad on the outer side of the coating layer 1 (9); The coating layer (9) comprises components including by weight: 10-15 parts of Ni, 5.0-8.0 parts of Cr, 10-14 parts of Co, 3.2-4.6 parts of B, 3.0-4.2 parts of Si, 4.0-6.5 parts of W, 0.5-0.8 parts of C, 1.0-2.3 parts of Mo, the balance is Fe and trace impurities, among which: 0.17≤(Co+B) / (Fe+Ni+Cr)≤0.26, 0.11≤(Si+Cr) / (Ni+Fe)≤0.20; The coating layer 2 (10) comprises components including by weight: 3.0-4.0 parts of Fe, 8-15 parts of Cr, 2.0-3.0 parts of B, 2.0-3.0 parts of Si, 2.2-4.5 parts of C, 24-29 parts of W, 3.0-4.0 parts of Ti, 0.1-0.2 parts of P, 1.0-2.0 parts of Co, the balance is Ni and trace impurities, 0.049≤(B+Co) / (Ni+Cr)≤0.095, 0.20≤(Co+W) / 2(Ni+Cr+C)≤0.

27.

2. The forged steel straightening roller structure according to claim 1, characterized in that: End covers (11) are respectively installed at both ends of the bearing seat (6), and the roller shaft (2) passes through the end covers (11); the roller shaft (2) is a stepped shaft, and a large diameter portion (21) is arranged in the middle of the roller shaft (2); a mounting groove is opened on the inner side of the middle sleeve (3), and the mounting groove is connected to the large diameter portion (21).

3. The forged steel straightening roller structure according to claim 2, characterized in that: The connecting groove comprises an oblique angle portion (12) and a surface notch (13); the surface notches (13) are provided in multiple groups and are arranged in parallel in the same direction; the oblique angle portion (12) is in a "W" shape.

4. The forged steel straightening roller structure according to claim 3, characterized in that: It also includes a mounting base plate (14), which is connected to the two sets of bearing seats (6) and is located at the bottom of the roller sleeve (1); The middle sleeve (3) comprises a spiral tube (15), and the spiral tube (15) is wound inside the middle sleeve (3); a return diameter portion (22) is provided in the middle of the roller shaft (2), and a return port is connected via the return diameter portion (22); The roller shaft (2) is provided with a guide groove (23), the guide groove (23) being in communication with the return diameter portion (22); and a connection port is provided on the guide groove (23); a fixing block (16) is provided in the middle sleeve (3), and is connected with a clamping column (17); the clamping column (17) is in communication with the fixing block (16), and a fixing cavity is provided in the fixing block (16), and the fixing cavity is in communication with the spiral tube (15).

5. The forged steel straightening roller structure according to claim 1, characterized in that: The bottom of the clamping column (17) is provided with a notch (171), the guide groove (23) is provided with an abutting bent rod (24), the rod body of the abutting bent rod (24) is rotatably connected to the guide groove (23), and a convex ball (25) is installed on the top, and the convex ball (25) is adapted to the notch (171); A horizontal portion (241) is provided at the bottom of the abutting bent rod (24), and the horizontal portion (241) abuts against the bottom of the clamping column (17).

6. A production process for a forged steel straightening roller structure as claimed in claim 1, characterized in that: The following steps are involved: Step 1, material preparation and pretreatment, after the raw materials of the roller sleeve (1) are prepared, they are cleaned and rust-removed; Step 2, smelting in an electric furnace, heating the raw materials of the roller sleeve (1) at a high temperature, and after melting, putting them into a mold to form an ingot into a block shape; Step 3, forging, taking out the block-shaped roller sleeve (1), forging and adjusting the position, and forging into a columnar structure; if the temperature drops too much, it needs to be returned to the furnace for heating; Step 4, a guide pin (18) is driven into the middle of the forged roller sleeve (1) so that the middle of the roller sleeve (1) has a central hole, forming a sleeve shape; Step 5, installing the prefabricated column (19) in the center hole, with one end of the prefabricated column (19) being chamfered and the other end extending outside the roller sleeve (1), and continuing forging; Step 6, take out the prefabricated column (19), prepare the forming roller shaft (2) in advance, connect the surface of the roller shaft (2) with the middle sleeve (3); install the roller shaft (2) and the middle sleeve (3) into the roller sleeve (1), and the chamfer of one end of the middle sleeve (3) abuts against the chamfer in the center hole; the horizontal distance difference A between the other end and the edge line of the center hole of the corresponding side; A pressing die (20) is installed on the outside of the roller sleeve (1), and the spacing of the pressing die (20) is adjusted so that the diameter of the roller sleeve (1) after being pressed down is larger than the designed required diameter; after the installation is completed, forging is continued until the workpiece is formed; and after the forging is completed, the workpiece is air-cooled; Step 7, pre-heat treatment, normalizing the workpiece to 875-930℃ for 2h; post-spheroidizing annealing, 640-750℃ for 3-5h; Step 8, performing ultrasonic flaw detection on the workpiece; and then performing rough machining on the surface of the roller sleeve (1) and the ends of both sides of the roller shaft (2); Step 9, modulated heat treatment, quenching the rough-machined workpiece, oil quenching at 950-1050°C for 0.5h; post-tempering at 640-680°C for 1h; Step 10: semi-finishing, finishing the size; and marking the bottom layer of the pattern (8) on the surface of the roller sleeve (1), with the pitch of the inclined path being 2-5 mm; Step 11, laser coating coating 1 (9), and the coating line is running around the roller surface; after coating, coating 1 (9) is air-cooled and the surface is polished; the powder of coating 1 (9) includes 10-15 parts of Ni, 5.0-8.0 parts of Cr, 10-14 parts of Co, 3.2-4.6 parts of B, 3.0-4.2 parts of Si, 4.0-6.5 parts of W, 0.5-0.8 parts of C, 1.0-2.3 parts of Mo, and the balance is Fe and trace impurities, wherein: 0.17≤(Co+B) / (Fe+Ni+Cr)≤0.26, 0.11≤(Si+Cr) / (Ni+Fe)≤0.20; Step 12, laser coating the second coating (10), and the coating line is running around the roller surface; after the coating of the second coating (10) is completed, it is air-cooled and the surface is polished; the powder of the first coating (9) is 3.0-4.0 parts of Fe, 8-15 parts of Cr, 2.0-3.0 parts of B, 2.0-3.0 parts of Si, 2.2-4.5 parts of C, 24-29 parts of W, 3.0-4.0 parts of Ti, 0.1-0.2 parts of P, 1.0-2.0 parts of Co, and the balance is Ni and trace impurities, 0.049≤(B+Co) / (Ni+Cr)≤0.095, 0.20≤(Co+W) / 2(Ni+Cr+C)≤0.27; Step 13, after spraying, remelting treatment, the remelting temperature is 1000 ~ 1200 ℃; static and dynamic balancing treatment; Step 14, in step 6, a U-shaped groove (4) is pre-formed on one end of the roller shaft (2), and corresponding pipes (5) of the inlet and return ports are installed; Then the corresponding bearing seat (6), end cover (11) and installation floor are installed to obtain the finished product.

7. The production process of the forged steel straightening roller structure according to claim 6, characterized in that: In step 10, the texture bottom layer (8) is tilted and divided into non-working areas (30) on both sides, and the texture bottom layer (8) is engraved on the curved surface in the non-working area (30); and the direction of the coating layer 1 (9) forms an angle of 2-3° with the texture bottom layer (8).

8. The production process of the forged steel straightening roller structure according to claim 7, characterized in that: In step 13, secondary quenching and tempering and recrystallization treatment can be performed, with the quenching temperature controlled at 800-950°C for 0.5h; tempering at 200-280°C for 1h; and air cooling the straightening rollers after quenching and tempering to room temperature.

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