High-strength wear-resistant straightening roll and production and manufacturing process

Abstract

The invention discloses a high-strength wear-resistant straightening roll and a production and manufacturing process, and relates to the technical field of straightening roll manufacturing. Comprising a roller sleeve and a roller shaft, the roller sleeve is provided with rhombus-shaped lines and covered with double coatings, and the roller sleeve comprises a lower coating and an upper coating; the lower-layer coating is prepared from the following components in parts by weight: 45 to 55 parts of Co, 25 to 30 parts of Cr, 8 to 12 parts of W, 3 to 5 parts of Mo, 0.8 to 1.2 parts of C, 1.0 to 2.0 parts of Si, 0.5 to 1.0 part of B, 0.5 to 1.5 parts of Y2O3, not more than 3.0 parts of Fe, not more than 2.0 parts of Ni and the balance of impurities; wherein (Cr + W + Mo) / Co is greater than or equal to 0.70 and less than or equal to 0.85; 0.025 < = (C + B) / (Co + Cr) < = 0.035; the upper coating is prepared from the following components in parts by weight: 5.5 to 8.5 parts of Al, 24.0 to 28.0 parts of Co, 21.0 to 25.0 parts of Cr, 17.0 to 21.0 parts of Fe, 18.0 to 22.0 parts of Ni, 3.0 to 6.0 parts of Ti, 0.1 to 0.3 part of C, 0.05 to 0.15 part of B and the balance of impurities; 1.0 < = (Co + Ni) / (Cr + Fe) < = 1.3; and Al / (Co + Cr + Fe + Ni) is greater than or equal to 0.15 and less than or equal to 0.20, so that the technical problems that a laser cladding alloy structure layer is easy to fall off and the curved surface is not changed during processing are solved.

Description

Technical Field

[0001] This invention relates to the field of straightening roller manufacturing technology, and in particular to a high-strength wear-resistant straightening roller and its manufacturing process. Background Technology

[0002] Straightening rollers are the core component of a straightening machine, used to eliminate plastic deformations such as bending, waviness, and warping that occur in metal sheets, strips, pipes, bars, or profiles during previous production processes, thus achieving the required straightness. Therefore, straightening rollers primarily withstand the temperature and wear of extrusion, resulting in deformation.

[0003] Laser cladding refers to the process of welding a coating material onto a surface at high temperature, giving the surface alloy properties. Referring to existing literature CN201210036736.5, a process for laser cladding high-hardness materials for the working surface of rolls, laser cladding is used to strengthen the working surface of the rolls. However, because the literature does not describe the corresponding structure of the cladding surface, existing methods of cladding on smooth surfaces are not conducive to bonding with the surface coating. Even if some groove structures exist, they are not combined with the number of cladding layers to achieve a stronger connection effect. The surface of straightening rolls is curved, so unlike traditional laser cladding processes, the depth of the cladding alloy layer will vary, resulting in uneven performance. Furthermore, most existing cladding materials are iron-based or nickel-based alloys, which individually possess high wear resistance but suffer from problems such as easy detachment from the roll surface and insufficient oxidation resistance. Summary of the Invention

[0004] To overcome the above deficiencies, this invention provides a high-strength wear-resistant straightening roller and its manufacturing process to solve the technical problems of easy peeling off of the laser cladding alloy structural layer and the invariance of surface processing.

[0005] To achieve the above objectives, the present invention adopts the following technical solution:

[0006] A high-strength wear-resistant straightening roller includes a roller sleeve and a roller shaft, the roller shaft and the roller sleeve are connected along the same axis, and the roller sleeve is provided with a diamond pattern.

[0007] The roller sleeve is covered with a double coating on the diamond pattern, including a lower coating and an upper coating.

[0008] The lower coating layer, by weight, comprises:

[0009] 45-55 parts Co, 25-30 parts Cr, 8-12 parts W, 3-5 parts Mo, 0.8-1.2 parts C, 1.0-2.0 parts Si, 0.5-1.0 parts B, 0.5-1.5 parts Y2O3, no more than 3.0 parts Fe, no more than 2.0 parts Ni and balance impurities;

[0010] The proportions satisfy the following conditions: 0.70≦(Cr+W+Mo) / Co≦0.85; 0.025≦(C+B) / (Co+Cr)≦0.035;

[0011] This invention employs a structure consisting of a lower cobalt-based transition layer and an upper high-entropy alloy functional layer. The cobalt-based alloy exhibits excellent high-temperature strength and thermal fatigue performance, while the high-entropy alloy, with its unique "cocktail effect" and slow diffusion effect, provides extremely high hardness, wear resistance, and high-temperature stability.

[0012] The purpose of the specified ratio "0.70≦(Cr+W+Mo) / Co≦0.85;" is to obtain high strength while maintaining sufficient plasticity and fracture toughness.

[0013] Cr, W, and Mo are the most important solid solution strengthening elements in the cobalt-based alloy of this lower coating. Their atomic radii differ from cobalt, and their dissolution in the cobalt matrix causes severe lattice distortion, hindering dislocation movement and thus significantly improving the alloy's high-temperature strength. Co is a matrix element, providing a face-centered cubic structure with good ductility, toughness, and resistance to thermal fatigue. When the ratio is too low (<0.70), the solid solution strengthening effect is insufficient, the coating's high-temperature strength is inadequate, and it is prone to plastic deformation under the high pressure and high temperature conditions of the straightening roller. When the ratio is too high (>0.85), an excessive amount of topologically close-packed phase easily forms in the alloy, leading to a sharp increase in coating brittleness, making it extremely prone to cracking and spalling under thermal shock.

[0014] The purpose of specifying the ratio "0.025≦(C+B) / (Co+Cr)≦0.035" is to obtain fine, uniformly dispersed hard phase particles, so that the coating can obtain good wear resistance; at the same time, the hard phase will not excessively cut the matrix, thus maintaining the adhesion between the lower coating and the roller sleeve matrix.

[0015] C and B are strong carbide / boride forming elements. In cobalt-chromium alloys, they preferentially combine with Cr, W, etc., to form hard phases such as tungsten carbide and boron carbide. These hard phases are dispersed in the matrix, playing a second-phase strengthening role and are key to improving wear resistance. When the (C+B) / (Co+Cr) ratio is too low (<0.025), the amount of hard phase is insufficient, and the macroscopic hardness and wear resistance of the coating do not meet the standards. When the ratio is too high (>0.035), there are too many hard phases, they are too coarse, or they form a continuous network, which can become crack initiation points and rapid propagation channels, seriously impairing the toughness and anti-stripping ability of the coating.

[0016] The top coating, by weight, comprises:

[0017] 5.5–8.5 parts Al, 24.0–28.0 parts Co, 21.0–25.0 parts Cr, 17.0–21.0 parts Fe, 18.0–22.0 parts Ni, 3.0–6.0 parts Ti, 0.1–0.3 parts C, 0.05–0.15 parts B and balance impurities;

[0018] 1.0≦(Co+Ni) / (Cr+Fe)≦1.3; 0.15≦Al / (Co+Cr+Fe+Ni)≦0.20.

[0019] The aim of the formulation is to obtain a microstructure in which the FCC and BCC phases coexist in an appropriate proportion, with a ratio of "1.0≦(Co+Ni) / (Cr+Fe)≦1.3". The FCC phase provides toughness and resistance to crack propagation, while the BCC phase provides extremely high hardness.

[0020] The purpose of the ratio "0.15≦Al / (Co+Cr+Fe+Ni)≦0.20" is to obtain an Al2O3 film while also forming the BCC phase structure of the alloy, thereby achieving greater hardness and plasticity.

[0021] Al is the core element for achieving high-temperature oxidation resistance in the upper coating. At high temperatures, it oxidizes to form a dense Al₂O₃ film, effectively preventing oxygen from diffusing inward. Simultaneously, Al is also a strong BCC phase-forming element. Excessive Al can cause the alloy to shift from being predominantly FCC phase to being predominantly BCC phase.

[0022] When the ratio is <0.15, the Al2O3 film is difficult to form or is not dense enough, resulting in insufficient oxidation resistance. When the ratio is >0.20, the proportion of BCC phase in the alloy is too high. Although the hardness may be higher, the coating becomes more brittle, the thermal shock resistance decreases, and brittle spalling is prone to occur under straightening impact loads.

[0023] A manufacturing process for a high-strength, wear-resistant straightening roll includes the following steps:

[0024] Finished product requirements: forging ratio of straightening rolls >3, overall quenching treatment, surface hardness >HRC52 within 60mm depth, and surface hardness range of HRC60-65 within 30mm depth;

[0025] Step 1: Material assembly and preparation

[0026] Different materials are selected to meet the requirements of finishing and hot straightening according to the working conditions; electric furnace + refining + vacuum treatment of steel ingots are adopted;

[0027] Step 2: Forging the billet

[0028] After the steel ingot is delivered, the process implementation plan is determined according to the specifications of the roller sleeve and shaft, and a large-tonnage electro-hydraulic hammer is selected for hammering; to ensure that the carbides in the structure of the forging billet are easily broken down and evenly distributed; the forging ratio of the forging billet is >3; before the forging billet is delivered, the dimensional and appearance defects need to be evaluated and preliminary flaw detection of the forging billet needs to be carried out.

[0029] Step 3, Spheroidizing Annealing

[0030] The forged billet is then placed in an annealing furnace for spheroidizing annealing treatment.

[0031] Step 4: Blank forming

[0032] After spheroidizing, the forging billet undergoes preliminary forming processing: the roller sleeve surface is turned to the curved end face, and rough boring and rough turning of the shaft are performed; then, non-destructive testing is carried out on the blank.

[0033] Step 5: Secondary softening and annealing

[0034] The blanks are precision machined to form roller sleeves and optical shafts, and then subjected to secondary annealing to remove surface work hardening and eliminate secondary stress.

[0035] Step 6: Tempering and Hardening

[0036] The optical axis is heated, hardened, and tempered in a furnace at high temperature, followed by quenching and tempering treatment to achieve an HB value of 240-290.

[0037] The surface of the roller sleeve is polished to remove the oxide and carbonization layer, and the cavity is filled with sealing material and lifting tools; then it is transferred to a quenching deep well furnace and heated to about 860-880℃ according to the set heat treatment process. After heat preservation, it is taken out of the furnace and quenched and then lifted into a water-based liquid pool. The quenching time and temperature are controlled according to the specifications.

[0038] Then, it is transferred to a cooling oil bath to be slowly cooled to room temperature, then lifted and unloaded; the hardening data is measured and controlled at HRC64~67, and then it is immediately transferred to the furnace for multiple tempering processes.

[0039] Step 7, Performance Tempering

[0040] After multiple tempering treatments with different properties, the hard and brittle cracking phenomenon was basically eliminated, and the hardness value reached the specified value: HRC62±2. After achieving the specified hardness value, an aging stress relief treatment was performed, followed by a second non-destructive testing.

[0041] Step 8: Finishing and shaping

[0042] The roller sleeve and the optical shaft are formed by turning, boring and milling in sequence, and the optical shaft forms the forming shaft; the roller sleeve has a central hole and needs to be machined with the forming shaft by basic hole interference fit; the basic interference is 3.5~4.5um, the roller sleeve curved surface is formed by CNC precision turning, and the rounded corner is formed by precision turning;

[0043] Step 9: Interference fit assembly

[0044] Place the roller sleeve in a set temperature chamber and heat it to about 120℃; keep it at that temperature for 1.5 to 2 hours, then remove it, fix it firmly, and measure the expansion value; then hang the forming shaft and insert it into the middle hole of the roller sleeve until it is in place, meeting the tolerance requirements of the roller sleeve to the edge of the forming shaft; check if the dimensional chain is correct.

[0045] Step 10: Finished Product Precision Machining

[0046] The roller sleeve and forming shaft are placed on a precision lathe for re-inspection, correction, and polishing to ensure that the workpiece roughness, surface finish, and dimensional accuracy meet the standards.

[0047] Step 11, Timeliness Processing

[0048] After the above process is completed, a low-temperature aging treatment is carried out again at a temperature of about 180°C to ensure stable technical parameter values ​​and overall performance index values.

[0049] Step 12: Surface diamond pattern processing

[0050] The bushing is fixed on the laser processing equipment. The rotating part rotates the working disk. First, the laser cutting head is aligned with the curved surface of the roller sleeve. It moves according to the contour curve groove on the working disk to achieve uniform depth cutting on the roller sleeve. The air supply pipe removes the surface cutting residue.

[0051] Step 13: Double-layer laser cladding process

[0052] Then rotate the worktable again to apply the laser cladding head to the diamond pattern. Let it stand for 2-3 hours, and then apply the upper coating on top of the lower coating.

[0053] Step 14: Flaw detection and dimensional accuracy inspection

[0054] Perform magnetic particle or dye penetrant testing on the surface of the roller sleeve, inspect the structural dimensional accuracy, record the results, and compile inspection record sheets and accompanying technical documents.

[0055] Step 15: Painting and warehousing.

[0056] The surface of the straightening roller is treated with rust prevention and coated with rust-preventive oil. The entire outer packaging is used to cover and secure the rollers, which are then tied tightly with packing straps and put into storage for shipment.

[0057] In a further technical solution, in step 12, the laser processing equipment includes a frame, on which a gripper assembly and a moving assembly are mounted;

[0058] The gripper assembly includes a chuck and a tailstock. A transverse lead screw is installed inside the frame. A nut seat is installed on the transverse lead screw and connected to the tailstock. A transverse motor is installed at the end of the transverse lead screw. The gripper assembly is used to clamp both ends of the roller sleeve.

[0059] The moving assembly includes a top frame, on the top of which is a transverse track. A drive unit and a moving frame are mounted on the transverse track. The drive unit drives the moving frame to move along the transverse track. A laser cladding head and a laser cutting head are mounted on the moving frame.

[0060] In a further technical solution, the driving component includes a drive motor and a drive gear, and the transverse track includes a transverse rack and a guide post. The drive gear meshes with the transverse rack, and the drive motor drives the drive gear to rotate. The body of the drive motor is mounted on the moving frame.

[0061] In a further technical solution, the working disc is provided with a first contour curve groove and a second contour curve groove, and both sets are the curvature of the surface of the contour roller sleeve.

[0062] A rotating shaft is installed in the middle of the working plate; a rotating motor is installed on the other side of the moving frame, a rotating gear is installed at the output end of the rotating motor, and a transmission gear is installed on the rotating shaft, with the rotating gear meshing with the transmission gear.

[0063] A limit rod is installed on the transmission gear, and a side plate is provided on the movable frame. The rotating shaft is connected to the side plate through a bearing. An arc-shaped groove is provided on the side plate, and the limit rod is inserted into the arc-shaped groove of the side plate.

[0064] In a further technical solution, two sets of working discs are provided, and multiple sets of fixing rods are installed between them for fixation; a side plate is installed on one side of the two sets of working discs and connected to it by a rotating shaft; the rotating shaft has a pull rod installed on the two sets of working discs, and the pull rod is sleeved on the two sets of fixing rods.

[0065] In a further technical solution, a frame-shaped rack plate is installed on the other side of the working disc, and a rack is provided inside the frame-shaped rack plate; symmetrical contoured curve groove one and contoured curve groove two are opened on the working disc; push rods are installed in both contoured curve groove one and contoured curve groove two, and connecting plates are installed at the ends of the push rods that extend out of the working disc, and the connecting plates constrain the two sets of push rods to move along contoured curve groove one or contoured curve groove two; a push motor is installed in the working disc, and a push gear is installed at the output end of the push motor and meshes with the frame-shaped rack plate for transmission;

[0066] Two sets of push rods are connected to fixed plates, and laser cladding heads and laser cutting heads are installed on the two sets of fixed plates respectively.

[0067] In a further technical solution, a guide plate and a lifting electric cylinder are installed on the fixed plate, the output end of the lifting electric cylinder is connected to the guide plate, and a laser cladding head and a laser cutting head are installed on the two sets of guide plates.

[0068] The present invention has the following beneficial effects:

[0069] 1) The lower coating material is clad at high temperature to form fine, uniformly dispersed hard phase particles, giving the coating excellent wear resistance. A diamond-shaped mesh is used to achieve strong adhesion of the lower coating. Simultaneously, the hard phase does not excessively tear the substrate, maintaining strong adhesion between the coating and the roller sleeve substrate. Furthermore, precise control of the boron content allows it to play a role in grain boundary purification and moderate strengthening, preventing grain boundary embrittlement caused by boron segregation.

[0070] 2) The material of the upper coating layer is laser high-temperature cladding to form a dense Al2O3 film and achieve self-generated antioxidant protection: by limiting the ratio, the excess Al elements form part of the FCC phase and transform into the BCC phase; achieving the ideal state of "FCC+BCC dual phase", so that the coating hardness reaches HV 800-1000 while still having a certain plastic deformation capacity.

[0071] 3) In the laser processing equipment of the present invention, the push motor drives the push gear to mesh with the rack inside the frame-shaped rack plate to move, and the connecting plates fixed on both sides of the frame-shaped rack plate drive the end of the push rod; the paired contoured curve grooves ensure the implementation effect of laser cutting and laser cladding. The rotary motor realizes the rotation of the entire working plate and limits it through the arc groove; the laser cutting head and laser cladding head are provided to realize bidirectional function. Attached Figure Description

[0072] Figure 1 This is a schematic diagram of the connection between the roller sleeve and the roller shaft proposed in this invention;

[0073] Figure 2 This is a schematic diagram of the diamond-shaped pattern on the roller sleeve proposed in this invention;

[0074] Figure 3 This is a schematic diagram of the laser processing equipment proposed in this invention;

[0075] Figure 4 for Figure 3 Enlarged view of part A;

[0076] Figure 5 This is a schematic diagram of the top frame structure of the present invention;

[0077] Figure 6 for Figure 5 Enlarged view of part B;

[0078] Figure 7This is a schematic diagram showing the connection between the drive gear and the transverse rack;

[0079] Figure 8 This is a top view of the mobile frame;

[0080] Figure 9 This is a schematic diagram of the side panel of the present invention;

[0081] Figure 10 This is a schematic diagram of the pull rod;

[0082] Figure 11 This is a schematic diagram of the laser cladding head and laser cutting head on the fixed plate of the present invention.

[0083] Legend: 1. Roller sleeve; 2. Roller shaft; 3. Diamond pattern; 4. Lower coating layer; 5. Upper coating layer;

[0084] 6. Gripper assembly; 61. Chuck; 62. Tailstock;

[0085] 7. Moving component; 71. Top frame; 72. Transverse track; 73. Moving frame; 74. Drive motor; 75. Drive gear; 721. Transverse rack; 722. Guide post; 76. Working plate; 761. Contouring curve groove one; 762. Contouring curve groove two;

[0086] 731. Rotating shaft; 732. Rotating motor; 733. Rotating gear; 734. Transmission gear; 735. Limiting rod; 736. Side plate; 737. Arc groove; 738. Fixing rod; 739. Pull rod; 77. Frame-type rack plate; 78. Connecting plate; 79. Push rod; 710. Fixing plate; 711. Lifting cylinder; 712. Guide plate; 713. Pushing motor; 714. Pushing gear;

[0087] 8. Laser cladding head; 9. Laser cutting head;

[0088] 10. Frame; 101. Horizontal lead screw; 102. Horizontal motor; Detailed Implementation

[0089] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0090] Example 1

[0091] like Figure 1 and 2 As shown, the present invention adopts the following technical solution:

[0092] A high-strength wear-resistant straightening roller includes a roller sleeve 1 and a roller shaft 2, the roller shaft 2 and the roller sleeve 1 are connected along the same axis, and the roller sleeve 1 is provided with a diamond pattern 3.

[0093] The diamond pattern on the roller sleeve 1 is covered with a double coating, including a lower coating 4 and an upper coating 5.

[0094] The lower coating layer 4, by weight, comprises:

[0095] 45-55 parts Co, 25-30 parts Cr, 8-12 parts W, 3-5 parts Mo, 0.8-1.2 parts C, 1.0-2.0 parts Si, 0.5-1.0 parts B, 0.5-1.5 parts Y2O3, no more than 3.0 parts Fe, no more than 2.0 parts Ni and balance impurities;

[0096] The proportions satisfy the following conditions: 0.70≦(Cr+W+Mo) / Co≦0.85; 0.025≦(C+B) / (Co+Cr)≦0.035;

[0097] The upper coating 5, by weight, comprises:

[0098] 5.5–8.5 parts Al, 24.0–28.0 parts Co, 21.0–25.0 parts Cr, 17.0–21.0 parts Fe, 18.0–22.0 parts Ni, 3.0–6.0 parts Ti, 0.1–0.3 parts C, 0.05–0.15 parts B and balance impurities;

[0099] 1.0≦(Co+Ni) / (Cr+Fe)≦1.3; 0.15≦Al / (Co+Cr+Fe+Ni)≦0.20.

[0100] The main reason for using the above-mentioned proportions in this application is that the proportion "0.70≦(Cr+W+Mo) / Co≦0.85;" aims to obtain high strength while maintaining sufficient plasticity and fracture toughness. The proportion "0.025≦(C+B) / (Co+Cr)≦0.035;" aims to obtain fine, uniformly dispersed hard phase particles, giving the coating good wear resistance; at the same time, the hard phase will not excessively cleave the matrix, maintaining the adhesion between the lower coating layer and the roller sleeve substrate. The proportion "1.0≦(Co+Ni) / (Cr+Fe)≦1.3;" aims to obtain a microstructure in which the FCC phase and BCC phase coexist in an appropriate proportion. The FCC phase provides toughness and resistance to crack propagation, while the BCC phase provides extremely high hardness. The purpose of the ratio "0.15≦Al / (Co+Cr+Fe+Ni)≦0.20" is to obtain an Al2O3 film while also forming the BCC phase structure of the alloy, thereby achieving greater hardness and plasticity.

[0101] Example 2

[0102] like Figure 3-11 As shown, another embodiment of the present invention is provided. Based on Example 1, a manufacturing process for a high-strength wear-resistant straightening roller includes the following steps:

[0103] (1) Material selection and preparation → (2) Forging of blanks → (3) Spheroidizing annealing → (4) Blank forming → (5) Secondary annealing → (6) Tempering and hardening of blanks → (7) Tempering treatment → (8) Primary machining → (9) Interference fitting → (10) Finished product → (11) Aging treatment → (12) Surface mesh texture processing → (13) Double-layer laser cladding → (14) Flaw detection and inspection → (13) Painting and warehousing.

[0104] Finished product requirements: forging ratio of straightening rolls >3, overall quenching treatment, surface hardness >HRC52 within 60mm depth, and surface hardness range of HRC60-65 within 30mm depth;

[0105] Step 1: Material assembly and preparation

[0106] Different materials are selected to meet the requirements of finishing and hot straightening according to the working conditions; electric furnace + refining + vacuum treatment of steel ingots are adopted;

[0107] Step 2: Forging the billet

[0108] After the steel ingot is delivered, the process implementation plan is determined according to the specifications of roller sleeve 1 and shaft, and a large-tonnage electro-hydraulic hammer is selected for striking; to ensure that the carbides in the structure of the forging billet are easily broken down and evenly distributed; the forging ratio of the forging billet is >3; before the forging billet is delivered, the dimensional and appearance defects need to be evaluated and preliminary flaw detection of the forging billet needs to be carried out.

[0109] Step 3, Spheroidizing Annealing

[0110] The forged billet is then placed in an annealing furnace for spheroidizing annealing treatment.

[0111] Step 4: Blank forming

[0112] After spheroidizing, the forging billet undergoes preliminary forming processing: the roller sleeve 1 roller surface is turned to the curved end face, and the hole is rough bored and the shaft is rough turned; then the blank is subjected to non-destructive testing.

[0113] Step 5: Secondary softening and annealing

[0114] The blanks are precision machined to form roller sleeve 1 and optical shaft, and then subjected to secondary annealing to remove surface work hardening and eliminate secondary stress.

[0115] Step 6: Tempering and Hardening

[0116] The optical axis is heated, hardened, and tempered in a furnace at high temperature, followed by quenching and tempering treatment to achieve an HB value of 240-290.

[0117] The surface of roller sleeve 1 is polished to remove the oxide and carbonization layer, and the cavity is filled with sealing material and lifting tool; then it is transferred to the quenching deep well furnace and heated to about 860-880℃ according to the set heat treatment process. After heat preservation, it is taken out of the furnace and quenched and then lifted into the water quality liquid pool. The quenching time and temperature are controlled according to the specifications.

[0118] Then, it is transferred to a cooling oil bath to be slowly cooled to room temperature, then lifted and unloaded; the hardening data is measured and controlled at HRC64~67, and then it is immediately transferred to the furnace for multiple tempering processes.

[0119] Step 7, Performance Tempering

[0120] After multiple tempering treatments with different properties, the hard and brittle cracking phenomenon was basically eliminated, and the hardness value reached the specified value: HRC62±2. After achieving the specified hardness value, an aging stress relief treatment was performed, followed by a second non-destructive testing.

[0121] Step 8: Finishing and shaping

[0122] Roller sleeve 1 and optical shaft are formed sequentially by turning, boring and milling, and optical shaft forms forming shaft; roller sleeve 1 has a central hole and needs to be machined with basic hole interference fit with forming shaft; the basic interference is 3.5~4.5um, roller sleeve 1 is formed by CNC precision turning of curved surface and precision turning of arc corner;

[0123] Step 9: Interference fit assembly

[0124] Place the roller sleeve 1 into the set temperature chamber and heat it to about 120℃; keep it at that temperature for 1.5 to 2 hours, take it out, fix it firmly, and measure the expansion value; then hang the forming shaft and insert it into the middle hole of the roller sleeve 1 until it is in place, meeting the tolerance requirements of the roller sleeve 1 to the edge of the forming shaft; check whether the dimensional chain is correct.

[0125] Step 10: Finished Product Precision Machining

[0126] Roller sleeve 1 and forming shaft are placed on a precision lathe for re-inspection, correction, and polishing to ensure that the workpiece roughness, surface finish, and dimensional accuracy meet the standards.

[0127] Step 11, Timeliness Processing

[0128] After the above process is completed, a low-temperature aging treatment is carried out again at a temperature of about 180°C to ensure stable technical parameter values ​​and overall performance index values.

[0129] Step 12: Surface diamond pattern processing

[0130] The bushing is fixed on the laser processing equipment. The rotating component rotates the working disk 76. First, the laser cutting head 9 is aligned with the curved surface of the roller sleeve 1. It moves according to the contour curve groove 761 on the working disk 76 to achieve uniform depth cutting on the roller sleeve 1. The air supply pipe removes the surface cutting residue.

[0131] Step 13: Double-layer laser cladding process

[0132] Then, rotate the working plate 76 again to apply the laser cladding head 8 to the diamond pattern. The laser cladding head 8 first applies the lower coating 4 to the diamond pattern. After standing for 2-3 hours, the upper coating 5 is applied to the lower coating 4.

[0133] Step 14: Flaw detection and dimensional accuracy inspection

[0134] Perform magnetic particle or dye penetrant testing on the surface of roller sleeve 1, inspect the structural dimensional accuracy, record the results, and compile an inspection record sheet and accompanying technical documents.

[0135] Step 15: Painting and Warehousing

[0136] The surface of the straightening roller is treated with rust prevention and coated with rust-preventive oil. The entire outer packaging is used to cover and secure the rollers, which are then tied tightly with packing straps and put into storage for shipment.

[0137] like Figure 3 As shown, in step 12, the laser processing equipment includes a frame 10, located in... Figure 3 At the bottom, a gripper assembly 6 and a moving assembly 7 are mounted on the frame 10;

[0138] like Figure 3 As shown, the lower gripper assembly 6 includes a chuck 61 and a tail frame 62. A transverse lead screw 101 is installed inside the frame 10. A nut seat is installed on the transverse lead screw 101 and connected to the tail frame 62. A transverse motor 102 is installed at the end of the transverse lead screw 101. The gripper assembly 6 is used to clamp both ends of the roller sleeve 1.

[0139] like Figure 3 The upper part of the moving assembly 7 includes a top frame 71, a transverse track 72 is provided on the top of the top frame 71, a drive unit and a moving frame 73 are installed on the transverse track 72, the drive unit drives the moving frame 73 to move along the transverse track 72; a laser cladding head 8 and a laser cutting head 9 are installed on the moving frame 73.

[0140] like Figure 5 and 6 As shown, the driving component includes a drive motor 74 and a drive gear 75. The transverse track 72 includes a transverse rack 721 and a guide post 722. The drive gear 75 meshes with the transverse rack 721, and the drive motor 74 drives the drive gear 75 to rotate. The body of the drive motor 74 is mounted on the movable frame 73.

[0141] like Figure 4 As shown, the working disc 76 is provided with contour curve groove 1 761 and contour curve groove 2 762 respectively, and both sets are the curvature of the surface of the contour roller sleeve 1, so as to realize synchronous movement and ensure the forming effect of laser cutting and laser cladding.

[0142] like Figure 8 As shown, a rotating shaft 731 is installed in the middle of a set of working discs 76; a rotating motor 732 is installed on the other side of the moving frame 73, a rotating gear 733 is installed at the output end of the rotating motor 732, a transmission gear 734 is installed on the rotating shaft 731, and the rotating gear 733 meshes with the transmission gear 734; a limit rod 735 is installed on the transmission gear 734, and a side plate 736 is provided on the moving frame 73. The rotating shaft 731 is connected to the side plate 736 by a bearing. An arc groove 737 is provided on the side plate 736, and the limit rod 735 is inserted into the arc groove 737 of the side plate 736.

[0143] Two sets of working discs 76 are provided, and multiple sets of fixing rods 738 are installed between them to support the two sets of push rods synchronously. A side plate 736 is installed on one side of the two sets of working discs 76 and is connected to it by a mounting shaft 731. A pull rod 739 is installed on the two sets of working discs 76 by the shaft 731, and the pull rod 739 is sleeved on the two sets of fixing rods 738.

[0144] like Figure 4 As shown, a frame-shaped rack plate 77 is installed on the other side of the working disk 76, and a rack is provided inside the frame-shaped rack plate 77; symmetrical contoured curve grooves 761 and 762 are formed on the working disk 76; push rods 79 are installed in both contoured curve grooves 761 and 762, and connecting plates 78 are installed at the ends of the push rods 79 extending out of the working disk 76. The connecting plates 78 constrain the two sets of push rods 79 to move along contoured curve groove 761 or contoured curve groove 762; A push motor 713 is installed inside the working plate 76. A push gear 714 is installed at the output end of the push motor 713 and meshes with the frame-shaped rack plate 77 for transmission. The push motor drives the push gear to mesh with the rack inside the frame-shaped rack plate to move. The connecting plates fixed on both sides of the frame-shaped rack plate drive the end of the push rod. The connecting plates are provided with waist-shaped holes or elliptical holes to realize the height change of the push rod. The paired contoured grooves ensure the implementation effect of laser cutting and laser cladding.

[0145] like Figure 11As shown, two sets of push rods 79 are respectively connected to fixed plates 710, and laser cladding heads 8 and laser cutting heads 9 are respectively installed on the two sets of fixed plates 710. Guide plates 712 and lifting cylinders 711 are installed on the fixed plates 710. The output end of the lifting cylinder 711 is connected to the guide plate 712, and the laser cladding heads 8 and laser cutting heads 9 are installed on the two sets of guide plates 712.

[0146] In this embodiment, the laser cladding head 8 and the laser cutting head 9 can both use the same continuous laser. The laser cutting head is equipped with high-pressure auxiliary gas to blow away the cutting slag, and the cladding head is equipped with a powder feeding pipe and a coolant pipe.

[0147] Finally, it should be noted that the above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A high-strength, wear-resistant straightening roller, characterized in that, It includes a roller sleeve (1) and a roller shaft (2), the roller shaft (2) and the roller sleeve (1) are connected along the same axis, and the roller sleeve (1) is provided with a diamond pattern (3); The roller sleeve (1) is covered with a double coating, including a lower coating (4) and an upper coating (5). The lower coating layer (4) comprises, by weight: 45-55 parts Co, 25-30 parts Cr, 8-12 parts W, 3-5 parts Mo, 0.8-1.2 parts C, 1.0-2.0 parts Si, 0.5-1.0 parts B, 0.5-1.5 parts Y2O3, no more than 3.0 parts Fe, no more than 2.0 parts Ni and balance impurities; The proportions satisfy the following conditions: 0.70≦(Cr+W+Mo) / Co≦0.85; 0.025≦(C+B) / (Co+Cr)≦0.035; The upper coating (5) comprises, by weight: 5.5–8.5 parts Al, 24.0–28.0 parts Co, 21.0–25.0 parts Cr, 17.0–21.0 parts Fe, 18.0–22.0 parts Ni, 3.0–6.0 parts Ti, 0.1–0.3 parts C, 0.05–0.15 parts B and balance impurities; 1.0≦(Co+Ni) / (Cr+Fe)≦1.3; 0.15≦Al / (Co+Cr+Fe+Ni)≦0.

20.

2. A manufacturing process for a high-strength, wear-resistant straightening roller, characterized in that, Includes the following steps: Finished product requirements: forging ratio of straightening rolls >3, overall quenching treatment, surface hardness >HRC52 within 60mm depth, and surface hardness range of HRC60-65 within 30mm depth; Step 1: Material assembly and preparation Different materials are selected to meet the requirements of finishing and hot straightening according to the working conditions; electric furnace + refining + vacuum treatment of steel ingots are adopted; Step 2: Forging the billet After the steel ingot is delivered, the process implementation plan is determined according to the specifications of the roller sleeve (1) and the shaft, and a large-tonnage electro-hydraulic hammer is selected to strike it; to ensure that the carbides in the structure of the forging billet are easily crushed and evenly distributed; the forging ratio of the forging billet is >3; before the forging billet is delivered, the dimensional and appearance defects need to be evaluated and preliminary forging billet flaw detection is performed; Step 3, Spheroidizing Annealing The forged billet is then placed in an annealing furnace for spheroidizing annealing treatment. Step 4: Blank forming After the forging billet is spheroidized, it undergoes preliminary forming processing: the roller sleeve (1) is turned from the roller surface to the curved end face, and the hole is rough bored and the shaft is rough turned; then the blank is subjected to non-destructive testing. Step 5: Secondary softening and annealing The blanks are precision machined to form roller sleeves (1) and optical shafts, and then subjected to secondary annealing to remove surface work hardening and eliminate secondary stress. Step 6: Tempering and Hardening The optical axis is heated, hardened, and tempered in a furnace at high temperature, followed by quenching and tempering treatment to achieve an HB value of 240-290. The surface of the roller sleeve (1) is polished to remove the oxide and carbonization layer, and the cavity is filled with sealing material and lifting tool; then it is transferred into the quenching deep well furnace and heated to about 860-880℃ according to the set heat treatment process flow. After heat preservation, it is taken out of the furnace and quenched and then lifted into the water quality liquid pool. The quenching time and temperature are controlled according to the specifications. Then, it is transferred to a cooling oil bath to be slowly cooled to room temperature, then lifted and unloaded; the hardening data is measured and controlled at HRC64~67, and then it is immediately transferred to the furnace for multiple tempering processes. Step 7, Performance Tempering After multiple tempering treatments with different properties, the hard and brittle cracking phenomenon was basically eliminated, and the hardness value reached the specified value: HRC62±2. After achieving the specified hardness value, an aging stress relief treatment is performed again, followed by a second non-destructive testing. Step 8: Finishing and shaping The roller sleeve (1) and the optical shaft are formed by turning, boring and milling in sequence, and the optical shaft forms the forming shaft; the roller sleeve (1) has a central hole and needs to be machined with the forming shaft by basic hole interference fit; the basic interference is 3.5~4.5um, the roller sleeve (1) is formed by CNC precision turning of curved surface and precision turning of arc corner; Step 9: Interference fit assembly Place the roller sleeve (1) into the set temperature chamber and heat it to about 120°C; keep it warm for 1.5 to 2 hours, take it out, fix it firmly, and measure the expansion value; then hang the forming shaft and insert it into the middle hole of the roller sleeve (1) until it is in place, so that the roller sleeve (1) also meets the tolerance requirements of the step of the forming shaft; check whether the dimensional chain is correct. Step 10: Finished Product Precision Machining The roller sleeve (1) and the forming shaft are placed on a precision lathe for inspection, correction and polishing to ensure that the workpiece roughness, surface finish and dimensional accuracy meet the standards. Step 11, Timeliness Processing After the above process is completed, a low-temperature aging treatment is carried out again at a temperature of about 180°C to ensure stable technical parameter values ​​and overall performance index values. Step 12: Surface diamond pattern processing The bushing is fixed on the laser processing equipment. The rotating component rotates the working disk (76). First, the laser cutting head (9) is aligned with the curved surface of the roller sleeve (1). It moves according to the contour curve groove (761) on the working disk (76) to achieve uniform depth cutting on the roller sleeve (1). The air supply pipe removes the surface cutting residue. Step 13: Double-layer laser cladding process Then rotate the work plate (76) again to apply the laser cladding head (8) to the diamond pattern. After standing for 2-3 hours, apply the upper coating (5) to the lower coating (4). Step 14: Flaw detection and dimensional accuracy inspection Magnetic particle or dye penetrant testing is performed on the surface of the roller sleeve (1), the structural dimensional accuracy is inspected, and the results are recorded. Inspection record sheets and random technical data are prepared. Step 15: Painting and warehousing. The surface of the straightening roller is treated with rust prevention and coated with rust-preventive oil. The entire outer packaging is used to cover and secure the rollers, and the rollers are tied tightly with packing straps before being put into storage and ready for shipment.

3. The manufacturing process for a high-strength wear-resistant straightening roller according to claim 2, characterized in that, In step 12, the laser processing equipment includes a frame (10) on which a gripper assembly (6) and a moving assembly (7) are mounted. The gripper assembly (6) includes a chuck (61) and a tail frame (62). A transverse lead screw (101) is installed inside the frame (10). A nut seat is installed on the transverse lead screw (101) and connected to the tail frame (62). A transverse motor (102) is installed at the end of the transverse lead screw (101). The gripper assembly (6) is used to clamp both ends of the roller sleeve (1). The moving component (7) includes a top frame (71), a transverse track (72) is provided on the top of the top frame (71), a drive and a moving frame (73) are mounted on the transverse track (72), the drive drives the moving frame (73) to move along the transverse track (72); a laser cladding head (8) and a laser cutting head (9) are mounted on the moving frame (73).

4. The manufacturing process of a high-strength wear-resistant straightening roller according to claim 3, characterized in that, The driving component includes a drive motor (74) and a drive gear (75). The transverse track (72) includes a transverse rack (721) and a guide post (722). The drive gear (75) meshes with the transverse rack (721), and the drive motor (74) drives the drive gear (75) to rotate. The body of the drive motor (74) is mounted on the moving frame (73).

5. The manufacturing process for a high-strength wear-resistant straightening roller according to claim 4, characterized in that, The working disc (76) is provided with contour curve groove one (761) and contour curve groove two (762), and both sets are the curvature of the surface of the contour roller sleeve (1). A rotating shaft (731) is installed in the middle of the working plate (76); a rotating motor (732) is installed on the other side of the moving frame (73), a rotating gear (733) is installed at the output end of the rotating motor (732), and a transmission gear (734) is installed on the rotating shaft (731), and the rotating gear (733) meshes with the transmission gear (734); A limiting rod (735) is installed on the transmission gear (734), and a side plate (736) is provided on the moving frame (73). The rotating shaft (731) is connected to the side plate (736) by a bearing. An arc groove (737) is provided on the side plate (736), and the limiting rod (735) is inserted into the arc groove (737) of the side plate (736).

6. The manufacturing process of a high-strength wear-resistant straightening roller according to claim 5, characterized in that, Two sets of working discs (76) are provided, and multiple sets of fixing rods (738) are installed between them for fixation; a side plate (736) is installed on one side of the two sets of working discs (76) and connected to it by a mounting shaft (731); the shaft (731) has a pull rod (739) installed on the two sets of working discs (76), and the pull rod (739) is sleeved on the two sets of fixing rods (738).

7. The manufacturing process of a high-strength wear-resistant straightening roller according to claim 6, characterized in that, A frame-shaped rack plate (77) is installed on the other side of the working disc (76), and a rack is provided inside the frame-shaped rack plate (77); symmetrical contoured curve groove one (761) and contoured curve groove two (762) are opened on the working disc (76); push rods (79) are installed in both contoured curve groove one (761) and contoured curve groove two (762), and a connecting plate (78) is installed at the end of the push rod (79) extending out of the working disc (76), and the connecting plate (78) constrains the two sets of push rods (79) to move along contoured curve groove one (761) or contoured curve groove two (762); a push motor (713) is installed inside the working disc (76), and a push gear (714) is installed at the output end of the push motor (713) and meshes with the frame-shaped rack plate (77) for transmission; A fixing plate (710) is connected to each of the two sets of push rods (79), and a laser cladding head (8) and a laser cutting head (9) are respectively installed on the two sets of fixing plates (710).

8. The manufacturing process of a high-strength wear-resistant straightening roller according to claim 7, characterized in that, The fixed plate (710) is equipped with a guide plate (712) and a lifting cylinder (711). The output end of the lifting cylinder (711) is connected to the guide plate (712). The two sets of guide plates (712) are equipped with a laser cladding head (8) and a laser cutting head (9).

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