Roll forging with high stability

Abstract

This utility model belongs to the field of rolling mill technology, specifically relating to a high-stability rolling mill forging. This forging includes a roll body and a roll neck, with an arc-shaped transition section between the roll body and the roll neck. The transition section adopts a continuously gradually changing smooth arc surface design, its outer contour forming a smooth streamlined curved surface from the end of the roll body, uniformly converging axially to the root of the roll neck. The roll body has multiple annular reinforcing ribs inside. In this utility model, the continuous streamlined arc-shaped transition section design between the roll body and the roll neck eliminates the stress concentration phenomenon caused by traditional right-angle transitions, forming a continuous and smooth stress transmission path, allowing the load to be uniformly transmitted axially to the root of the roll neck, reducing the risk of crack initiation. This rolling mill forging, combined with the three-dimensional mesh support system of annular reinforcing ribs and connecting ribs inside the roll body, improves the rolling mill's bending rigidity and torsional performance, suppresses radial deformation during high-speed operation, and achieves a balance between lightweight and dynamic stability.

Description

Technical Field

[0001] This utility model relates to the field of rolling mill technology, and in particular to a rolling mill forging with high stability. Background Technology

[0002] As a core component in metallurgical rolling equipment and machinery manufacturing, rolling mill forgings are widely used in hot rolling, cold rolling, and sheet metal forming processes in industries such as steel, non-ferrous metals, and heavy equipment. Their function is to efficiently transfer plastic deformation energy to the processed material through contact between the high-strength, high-wear-resistant roll surface and the rolled material, thereby achieving dimensional accuracy control and surface quality optimization for sheet or profile materials. With the continuous improvement of modern industry's requirements for rolling efficiency, product precision, and equipment service life, the structural design, material properties, and operational stability of rolling mill forgings have gradually become key factors affecting the overall efficiency of rolling production lines. In recent years, the transformation and upgrading of the metallurgical industry has placed higher demands on rolling mills: on the one hand, they need to adapt to the dynamic load impact and thermo-mechanical coupling effect under high-speed rolling conditions; on the other hand, they need to maintain long-term stable geometric dimensions and fatigue resistance in complex alternating stress environments. Against this backdrop, improving the overall stability of rolling mill forgings through structural innovation and material composite technology has become one of the important directions for technological development in the industry.

[0003] In traditional roll design, the transition zone between the roll body and the roll neck adopts a right-angle or stepped structure, resulting in a high stress concentration coefficient and easy fatigue cracking. The welded or sprayed wear-resistant layer is prone to interlayer delamination during high-temperature rolling due to its low interfacial bonding strength. There is no stress dispersion structure inside the roll neck, resulting in significant stress concentration at the root under alternating loads and insufficient fatigue life. Weight reduction designs often adopt simple hollow structures, which leads to a decrease in local strength and is prone to inducing centrifugal force imbalance during high-speed rotation. Therefore, we propose a roll forging with high stability. Utility Model Content

[0004] The purpose of this invention is to provide a roll forging with high stability to solve the problems mentioned in the background art.

[0005] To solve the above-mentioned technical problems, this utility model provides a high-stability roll forging, including a roll body and a roll neck. An arc-shaped transition section is provided between the roll body and the roll neck. The transition section adopts a continuously gradually changing smooth arc surface design. Its outer contour forms a smooth streamlined curved surface from the end of the roll body and uniformly converges to the root of the roll neck along the axial direction. Multiple annular reinforcing ribs are provided inside the roll body. The annular reinforcing ribs are evenly distributed along the axial direction of the roll body, and connecting ribs are arranged around the multiple annular reinforcing ribs.

[0006] As a preferred embodiment of this utility model, the surface of the roller body is covered with a composite wear-resistant layer, which is formed by combining an outer high-chromium cast iron layer and an inner alloy steel substrate through a hot isostatic pressing process.

[0007] The technical effects of adopting the above-mentioned further solutions are as follows: the high hardness of the high-chromium cast iron layer improves the wear resistance of the roll surface, while the alloy steel matrix ensures the overall toughness; the hot isostatic pressing process enables the interface of the two materials to form a metallurgical bond, avoiding the risk of interlayer peeling caused by traditional welding or spraying, and significantly extending the service life of the roll under high-temperature rolling conditions.

[0008] As a preferred embodiment of this utility model, a plurality of stress dispersion holes are evenly distributed along the axial direction inside the roller neck. The stress dispersion holes are conical, with their large ends facing the roller body and their small ends facing the end of the roller neck.

[0009] The technical effects of adopting the above-mentioned further solutions are as follows: the conical hole design can guide the alternating stress to dissipate along the gradient of the hole wall, reducing the stress concentration coefficient at the root of the roll neck; the setting of the large end close to the high stress area (roll body side) optimizes the stress transmission path, reduces the probability of fatigue crack initiation, and improves the stability of the roll neck under long-term dynamic load.

[0010] As a preferred embodiment of this utility model, the roller body is provided with a honeycomb-shaped weight reduction cavity, which is filled with wear-resistant alloy particles.

[0011] As a preferred embodiment of this utility model, the wear-resistant alloy particles are fixedly connected to the roller body through a high-temperature sintering process.

[0012] The technical effects of adopting the above-mentioned further solutions are as follows: the honeycomb structure reduces the weight of the roll body while uniformly bearing the rolling pressure through the hexagonal hole walls, avoiding local deformation; filling with wear-resistant alloy particles can enhance the local wear resistance of the weight reduction cavity area and prevent the roll body strength from decreasing due to weight reduction; high-temperature sintering enables the particles to form a dense metallurgical bond with the roll body matrix, preventing the particles from detaching from the cavity due to centrifugal force when the roll rotates at high speed, ensuring the long-term stability of the weight reduction cavity structure, while the sintered layer can inhibit crack propagation.

[0013] As a preferred embodiment of this utility model, the end face of the roller body is provided with a hardening treatment layer.

[0014] The technical effects of adopting the above-mentioned further solutions are: the hardened layer effectively resists end face friction damage during mill assembly, reduces the axial positioning deviation of the roll caused by end face wear, and its surface roughness can further reduce the frictional resistance with the bearing housing.

[0015] As a preferred embodiment of this utility model, the end of the roller neck is provided with a flange, and the flange has a plurality of through holes evenly distributed thereon.

[0016] The technical effects of adopting the above-mentioned further solutions are: the through-hole design balances the circumferential stress distribution of the flange and avoids local plastic deformation caused by bolt preload; at the same time, it reduces the flange mass, reduces the rotational inertia of the rolls, and improves the dynamic response performance during high-speed rolling.

[0017] As a preferred embodiment of this utility model, the roller body is made of 42CrMoV alloy forged steel, and the surface of the roller neck is subjected to carburizing and quenching treatment.

[0018] The technical effects of adopting the above-mentioned further solutions are: 42CrMoV alloy forged steel has both high strength and resistance to thermal fatigue, and is suitable for the thermo-mechanical coupling conditions during the rolling process; the surface of the roll neck is carburized and quenched to form a gradient hardness layer (the surface hardness is ≥HRC55, and the core maintains HRC35-40), which ensures wear resistance while avoiding the risk of brittle fracture.

[0019] Compared with the prior art, the beneficial effects of this utility model are:

[0020] 1. In this utility model, the continuous streamlined arc transition section between the roll body and the roll neck eliminates the stress concentration phenomenon caused by the traditional right-angle transition, forming a continuous and smooth stress transmission path, so that the load is uniformly transmitted to the root of the roll neck along the axial direction, reducing the risk of crack initiation; combined with the three-dimensional mesh support system of the internal annular reinforcing ribs and connecting ribs of the roll body, the bending rigidity and torsional performance of the roll are improved, the radial deformation during high-speed operation is suppressed, and a balance between lightweight and dynamic stability is achieved.

[0021] 2. In this invention, the hot isostatic pressing process of the composite wear-resistant layer on the roller body surface enhances the wear resistance of the outer high-chromium cast iron layer, while the inner alloy steel matrix ensures overall toughness. The metallurgical bonding interface avoids the risk of interlayer delamination, significantly extending the service life under high-temperature rolling conditions. Combined with the honeycomb weight-reducing cavity (filled with high-temperature sintered wear-resistant alloy particles), it reduces weight while enhancing local wear resistance, preventing strength reduction due to weight reduction.

[0022] To make the above-mentioned objectives, features and advantages of this utility model more apparent and understandable, preferred embodiments are described below in detail with reference to the accompanying drawings. Attached Figure Description

[0023] To more clearly illustrate the specific embodiments of this utility model or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this utility model. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0024] Figure 1This is a schematic diagram of the overall structure of this utility model;

[0025] Figure 2 This is a schematic diagram of the internal structure of the composite wear-resistant layer of this utility model.

[0026] Figure 3 This is a side view of the internal structure of the roller body of this utility model.

[0027] Figure 4 This is a schematic diagram of the overall planar internal structure of this utility model.

[0028] Legend: 1. Roller body;

[0029] 2. Roller neck; 201. Stress dispersion holes;

[0030] 3. Transition section;

[0031] 4. Circular reinforcing ribs; 401. Connecting ribs;

[0032] 5. Composite wear-resistant layer; 501, outer high-chromium cast iron layer; 502, inner alloy steel substrate;

[0033] 6. Weight reduction cavity; 601 wear-resistant alloy particles;

[0034] 7. Hardened treatment layer;

[0035] 8. Flange; 801. Through hole. Detailed Implementation

[0036] To make the objectives, technical solutions, and advantages of the embodiments of this utility model clearer, the technical solutions of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this utility model. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of this utility model.

[0037] Example 1

[0038] like Figure 1-4As shown, this utility model provides a technical solution: a high-stability roll forging, including a roll body 1 and a roll neck 2, with a transition section 3 between the roll body 1 and the roll neck 2. The outer diameter of the transition section 3 gradually decreases from the roll body 1 to the roll neck 2. Multiple annular reinforcing ribs 4 are uniformly distributed along the axial direction of the roll body 1, and connecting ribs 401 are arranged around each of the multiple annular reinforcing ribs 4. Through the arc-shaped transition section 3 between the roll body 1 and the roll neck 2, a continuous and smooth stress transmission path is formed. The streamlined curved surface eliminates the stress concentration phenomenon of traditional right-angle transitions, allowing the load to be uniformly transmitted axially to the root of the roll neck 2. The uniformly distributed annular reinforcing ribs 4 inside the roll body 1 and the surrounding connecting ribs 401 work together to form a three-dimensional mesh support system, significantly increasing stability. The roll exhibits strong overall bending rigidity and torsional resistance, effectively dispersing alternating stress and suppressing radial deformation under high-speed operation, while ensuring uniformity of roll body wall thickness. The smooth arc surface design also enhances material processing continuity, avoiding the risk of microcrack propagation caused by abrupt changes in cross-section, achieving a balance between lightweight and dynamic stability. The surface of the roll body 1 is covered with a composite wear-resistant layer 5, which is formed by combining an outer high-chromium cast iron layer 501 and an inner alloy steel substrate 502 through a hot isostatic pressing process. The high hardness of the high-chromium cast iron layer enhances the wear resistance of the roll surface, while the alloy steel substrate ensures overall toughness. The hot isostatic pressing process creates a metallurgical bond between the two material layers, avoiding the risk of interlayer delamination caused by traditional welding or spraying, and significantly extending the service life of the roll under high-temperature rolling conditions.

[0039] Example 2

[0040] like Figure 1-4As shown, this utility model provides a technical solution: a high-stability roll forging, wherein multiple stress dispersion holes 201 are uniformly distributed along the axial direction inside the roll neck 2. The stress dispersion holes 201 are conical, with their large ends facing the roll body 1 and their small ends facing the end of the roll neck 2. The conical hole design can guide the alternating stress to dissipate along the gradient of the hole wall, reducing the stress concentration coefficient at the root of the roll neck 2. The setting of the large end close to the high stress area (roll body 1 side) optimizes the stress transmission path, reduces the probability of fatigue crack initiation, and improves the stability of the roll neck 2 under long-term dynamic load. Qualitatively, the roll body 1 has a honeycomb-shaped weight-reduction cavity 6 inside, which is filled with wear-resistant alloy particles 601. The wear-resistant alloy particles 601 are fixedly connected to the roll body 1 body through a high-temperature sintering process. The honeycomb structure reduces the weight of the roll body 1 while uniformly bearing the rolling pressure through the hexagonal hole walls, avoiding local deformation. Filling with wear-resistant alloy particles 601 can enhance the local wear resistance of the weight-reduction cavity 6 area and prevent the roll body 1 from losing strength due to weight reduction. High-temperature sintering forms a dense metallurgical bond between the particles and the roll body 1 matrix, preventing high-speed rolling. During rotation, the particles detach from the cavity due to centrifugal force, ensuring the long-term stability of the weight-reducing cavity 6. Simultaneously, the sintered layer inhibits crack propagation. The end face of the roll body 1 is provided with a hardened layer 7, which effectively resists end-face friction damage during mill assembly, reducing axial positioning deviation of the roll due to end-face wear. Its surface roughness further reduces frictional resistance with the bearing housing. The end of the roll neck 2 is provided with a flange 8, on which multiple through holes 801 are evenly distributed. The through holes 801 are designed to balance the circumferential stress distribution of the flange 8, preventing stress caused by bolt preload. This reduces localized plastic deformation; it also reduces the mass of flange 8, decreases the moment of inertia of the rolls, and improves the dynamic response performance during high-speed rolling. The material of roll body 1 is 42CrMoV alloy forged steel, and the surface of roll neck 2 is carburized and quenched. 42CrMoV alloy forged steel has both high strength and resistance to thermal fatigue, adapting to the thermal-mechanical coupling conditions during the rolling process. The carburized and quenched surface of roll neck 2 forms a gradient hardness layer (surface hardness ≥ HRC55, core maintains HRC35-40), ensuring wear resistance while avoiding the risk of brittle fracture.

[0041] The working process of this utility model is as follows: Stress concentration is eliminated through a continuous streamlined arc transition design between the roller body 1 and the roller neck 2. Internal annular reinforcing ribs 4 and connecting ribs 401 construct a three-dimensional mesh support to enhance overall rigidity. The surface of the roller body 1 is covered with a composite wear-resistant layer 5, which is formed by combining an outer high-chromium cast iron layer 501 and an inner alloy steel substrate 502 through a hot isostatic pressing process. The high hardness of the outer high-chromium cast iron layer 501 enhances the wear resistance of the roller surface, while the inner alloy steel substrate 502 ensures overall toughness. The hot isostatic pressing process creates a metallurgical bond between the two material layers, avoiding the risk of interlayer delamination caused by traditional welding or spraying. This significantly extends the service life of the rolls under high-temperature rolling conditions. The roll neck 2 has a built-in conical stress dispersion hole 201 to optimize the load transfer path. The honeycomb weight reduction cavity 6 is filled with sintered wear-resistant alloy particles 601 to achieve synergy between lightweighting and local strengthening. The end face hardening treatment layer 7 inhibits assembly wear and reduces frictional resistance. The flange 8 through hole 801 layout balances circumferential stress and rotational inertia. Combined with the 42CrMoV alloy forged steel matrix and gradient carburizing and quenching process, a roll system that takes into account high strength, thermal fatigue resistance, dynamic stability and wear resistance is formed. Finally, through the systematic combination of structural optimization and material treatment, long-term stable operation under rolling conditions is achieved.

[0042] All the devices selected in this application are general standard parts or components known to those skilled in the art. Their structures and principles can be learned by those skilled in the art through technical manuals or conventional experimental methods.

[0043] In the description of the embodiments of this utility model, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model based on the specific circumstances.

[0044] In the description of this utility model, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the accompanying drawings and are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this utility model. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0045] Based on the above-described preferred embodiments of this utility model, and through the foregoing description, those skilled in the art can make various changes and modifications without departing from the technical concept of this utility model. The technical scope of this utility model is not limited to the contents of the specification, but must be determined according to the scope of the claims.

Claims

1. A roll forging having high stability, comprising a roll body (1) and a roll neck (2), characterized in that: An arc-shaped transition section (3) is provided between the roller body (1) and the roller neck (2). The transition section (3) adopts a smooth arc surface design with continuous gradient. Its outer contour forms a smooth streamlined curved surface from the end of the roller body (1) and uniformly converges to the root of one end of the roller neck (2) along the axial direction. Multiple annular reinforcing ribs (4) are provided inside the roller body (1). The annular reinforcing ribs (4) are evenly distributed along the axial direction of the roller body (1). Connecting ribs (401) are arranged around the multiple annular reinforcing ribs (4).

2. The roll forging having high stability according to claim 1, characterized by: The surface of the roller body (1) is covered with a composite wear-resistant layer (5), which is formed by combining an outer high-chromium cast iron layer (501) and an inner alloy steel substrate (502) through a hot isostatic pressing process.

3. The roll forging having high stability according to claim 1, wherein: Multiple stress-dispersing holes (201) are evenly distributed along the axial direction inside the roller neck (2). The stress-dispersing holes (201) are conical, with their large end facing the roller body (1) and their small end facing the end of the roller neck (2).

4. The roll forging according to claim 1, wherein: The roller body (1) is provided with a honeycomb-shaped weight reduction cavity (6), which is filled with wear-resistant alloy particles (601).

5. A roll forge piece having high stability according to claim 4, characterized in that: The wear-resistant alloy particles (601) are fixedly connected to the roller body (1) body through a high-temperature sintering process.

6. The roll forge piece having high stability according to claim 1, wherein: The end face of the roller body (1) is provided with a hardened treatment layer (7).

7. The roll forge piece having high stability according to claim 1, wherein: The end of the roller neck (2) is provided with a flange (8), and a plurality of through holes (801) are evenly distributed on the flange (8).

8. The roll forge piece having high stability according to claim 1, wherein: The material of the roller body (1) is 42CrMoV alloy forged steel, and the surface of the roller neck (2) is carburized and quenched.

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