Grinding method for roller and grinding machine

Abstract

The invention provides a grinding method for a roller and a grinding machine, and relates to the technical field of machining. The grinding method for the roller comprises the following steps that a groove is formed in the roller face of the end of the roller to be machined, and a first roller is obtained; acquiring a surface profile curve of the first roller; based on grinding treatment parameters, grinding treatment is conducted on the first roller, and a second roller is obtained; wherein the grinding treatment parameters comprise grinding current, and the grinding current is used for representing the maximum limiting current determined on the basis of the surface profile curve. The grooves are formed in the roller surface of the end of the roller, the maximum diameter change value of the surface of the roller is increased, the surface profile curve of the roller is made to change, then the grinding machine control system improves the maximum limiting current set value, traditional grinding current limitation is broken through, the grinding process can be stably operated under the higher current condition, and the grinding efficiency is improved. The material removal efficiency is improved; and the processing time is shortened.

Description

Technical Field

[0001] This application relates to the field of machining technology, and in particular to a grinding method and grinding machine for rolling mill rolls. Background Technology

[0002] During long-term use, rolls will develop surface defects such as wear, roundness error, and irregular surface contours, which need to be repaired by grinding.

[0003] However, to repair surface defects in the rolls, it is necessary to remove cracks on the roll surface, which requires a large machining allowance. Due to the large machining allowance and the fact that the grinding current is limited by the maximum current limit of the grinding machine, the repair process takes a very long time, which seriously affects production efficiency. Summary of the Invention

[0004] To address the aforementioned problems in the prior art, this application provides a grinding method and grinding machine for rolling mill rolls. The technical problem to be solved by this application is achieved through the following technical solution: In a first aspect, this application provides a grinding method for rolls, comprising the following steps: A groove is formed on the end face of the roll to be processed to obtain the first roll; Obtain the surface profile curve of the first roll; The first roll is ground based on the grinding parameters to obtain the second roll; wherein the grinding parameters include grinding current, which is used to characterize the maximum limiting current determined based on the surface profile curve.

[0005] In one feasible approach, the grinding parameters further include: At least one of X-axis gain value, Y-axis gain value, and grinding wheel rotation cycle, wherein the X-axis gain value is used to control the feed servo stiffness of the grinding process, the Y-axis gain value is used to control the traverse speed variation of the grinding process, and the grinding wheel rotation cycle is used to control the rotational speed variation of the grinding wheel during the grinding process.

[0006] In one feasible embodiment, the grinding method further includes: If the diameter of the second roll is larger than the preset diameter, the second roll is used as the roll to be processed. If the diameter of the second roll is less than or equal to the preset diameter, the roll being ground is determined to be the target roll.

[0007] In one feasible manner, the step of grinding the first roll to obtain the second roll includes: The reciprocating section of the first roll is subjected to reciprocating grinding. The interval section of the first roll is smoothed and ground so that the diameter of the interval section is equal to the diameter of the reciprocating section, thus obtaining the second roll. The first roll includes the reciprocating section and the interval section located on at least one side of the reciprocating section.

[0008] In one feasible implementation, the interval segment includes the groove; The radius difference between the second roll and the first roll is greater than or equal to the depth of the groove.

[0009] In one feasible manner, the reciprocating grinding process is performed multiple times; The transverse speed of the reciprocating grinding process is 100~300mm / min.

[0010] In one feasible manner, during the reciprocating grinding process, the diameter variation of the reciprocating section is 0.2~0.3 mm; The grinding current is 80~100A.

[0011] In one feasible implementation, the depth of the groove is 0.2~0.5mm; The axial length of the groove is 200~300mm.

[0012] In one feasible manner, the surface profile curve is used to characterize the variation in the roll surface diameter of the first roll; The maximum limiting current is determined based on the maximum diameter change of the first roll surface.

[0013] In a second aspect, this application provides a grinding machine for rolls, used to implement the grinding method provided in the first aspect of this application, the grinding machine comprising: The worktable is used to support the rolling mill rolls; Grinding wheels are used for grinding rolls; The sensing module is used to acquire the surface profile curve of the roll; A control module is used to determine the maximum limiting current based on the surface profile curve and control the operation of the grinding wheel based on grinding processing parameters, wherein the grinding processing parameters include grinding current, which is used to characterize the maximum limiting current.

[0014] Compared with the prior art, the beneficial effects of this application are as follows: This application increases the maximum diameter variation of the roll surface by forming a groove on the roll end, thereby changing the surface profile curve of the roll. This allows the grinding machine control system to increase the maximum limiting current setting, thus breaking through the traditional grinding current limitation. This enables the grinding process to operate stably under higher current conditions, improving material removal efficiency and shortening processing time. Attached Figure Description

[0015] The accompanying drawings, which are included to provide a further understanding of this application and form part of this application, illustrate exemplary embodiments of this application and are used to explain this application, but do not constitute an undue limitation of this application. In the drawings: Figure 1 A schematic diagram of the steps of a grinding method for a rolling mill according to an embodiment of this application is shown. Detailed Implementation

[0016] The present application will now be described in detail with reference to the accompanying drawings and specific embodiments and application scenarios. Obviously, the described embodiments are only a part of the embodiments of the present application, and not all of them. Unless otherwise specified, the following embodiments and features can be combined with each other. All other embodiments obtained by those skilled in the art based on the embodiments of the present application are within the scope of protection of the present application.

[0017] The terms "first," "second," etc., used in the specification and claims of this application are used to distinguish similar objects and not to describe a specific order or sequence. It should be understood that such use of data can be interchanged where appropriate so that embodiments of this application can be implemented in orders other than those illustrated or described herein, and the objects distinguished by "first," "second," etc., are generally of the same class and the number of objects is not limited; for example, a first object can be one or more. Furthermore, in the specification and claims, "and / or" indicates at least one of the connected objects, and the character " / " generally indicates that the preceding and following objects are in an "or" relationship.

[0018] Please see Figure 1 , Figure 1 A schematic diagram of the steps of a grinding method for a rolling mill roll according to an embodiment of this application is shown.

[0019] This application provides a grinding method for rolling mill rolls, comprising the following steps: S1: A groove is formed on the end face of the roll to be processed to obtain the first roll.

[0020] Specifically, the roll to be processed is mounted on the worktable of a grinding machine, and a grinding wheel or special machining tool is used to form a groove on the roll surface at the end of the roll. Further, the groove is an annular groove, meaning it is continuous along the circumference of the roll to be processed, creating a region with a reduced diameter at the roll end. Preferably, the groove depth is 0.1~0.3mm, meaning the diameter of the groove region is 0.2~0.6mm smaller than the diameter of the roll to be processed, and the axial length of the groove is 200~300mm.

[0021] In one embodiment, before step S1, the roll surface of the roll to be processed is flattened so that the diameter of the roll at each position along the axial direction is the same.

[0022] S2: Obtain the surface profile curve of the first roll.

[0023] Specifically, the surface profile curve of the first roll is measured using the grinding machine's sensing module. Further, the sensing module moves along the roll's axial direction to acquire diameter data at each axial position and generates the surface profile curve. The surface profile curve characterizes the diameter variation relationship at each axial position of the roll.

[0024] S3: Based on the grinding parameters, the first roll is ground to obtain the second roll. The grinding parameters include the grinding current, which characterizes the maximum limiting current determined based on the surface profile curve.

[0025] Specifically, the grinding current is a closed-loop control parameter for the grinding machine's load. During grinding, the grinding machine collects the current value of the grinding wheel drive motor in real time, compares the actual current with the set grinding current, and automatically adjusts the position of the grinding wheel in the X-axis direction based on the comparison result to maintain the actual current value at the grinding current. Further, when the actual current is detected to be lower than the grinding current, it indicates that the current grinding load is low. The grinding machine control module controls the grinding wheel to move along the positive X-axis, causing the grinding wheel to cut further towards the roll, thereby increasing the grinding depth, increasing the grinding load, and raising the actual current to the grinding current. When the actual current is detected to be higher than the grinding current, it indicates that the current grinding load is too high. The grinding machine control system controls the grinding wheel to move along the negative X-axis, moving the grinding wheel away from the roll surface, thereby reducing the grinding depth, lowering the grinding load, and reducing the grinding current. When the actual current is equal to the grinding current, the grinding wheel maintains its current X-axis position, keeping the grinding process stable. When the diameter of the roll surface remains unchanged, the actual current of the grinding wheel is constant, which is the grinding current. Therefore, increasing the grinding current can increase the grinding depth of the grinding wheel, thereby improving the material removal efficiency.

[0026] Specifically, the maximum limiting current is determined based on the maximum diameter change of the first roll surface. During the grinding process, the grinding machine control module typically determines the maximum limiting current based on the roll's surface profile curve. Specifically, the grinding machine obtains the roll surface profile curve by measuring the diameter values ​​at various axial positions of the roll and calculates the maximum diameter change of this profile curve. The grinding machine control module assesses the maximum possible depth of cut during grinding based on the maximum diameter change and calculates the allowable maximum limiting current based on this maximum depth of cut. Since a larger maximum diameter change corresponds to a larger theoretically allowable maximum grinding depth of cut and a higher maximum allowable load capacity of the grinding machine system, the maximum limiting current that the grinding machine control module can set is also larger. In traditional roll grinding, because the roll surface is relatively flat, its maximum diameter change is small, and the maximum limiting current set by the grinding machine control module is therefore lower. The maximum limiting current is the maximum grinding current value that the grinding machine can set. Therefore, the grinding current is limited by the maximum limiting current and cannot be further increased, thus the grinding process can only be carried out under low current conditions, limiting material removal efficiency.

[0027] Furthermore, the larger the maximum diameter variation, the higher the grinding current that the grinding machine control module can set. Therefore, in this embodiment, by setting a groove at the end of the roll, a region with a reduced diameter is formed at the roll end, thereby reducing the minimum diameter of the roll surface profile curve and increasing the maximum diameter variation. The grinding machine control system calculates the maximum limiting current based on the increased maximum diameter variation, allowing the grinding machine to use a higher grinding current for grinding. Therefore, without changing the rated power of the grinding machine, by changing the characteristics of the roll surface profile curve, the grinding machine control system increases the maximum limiting current setting, enabling the grinding process to operate stably under higher current conditions, thereby improving material removal efficiency and grinding efficiency.

[0028] In this embodiment, the control module of the grinding machine determines the maximum diameter change value ΔD of the first roll surface based on the surface profile curve. max ΔD max =D max D min , where D max D is the maximum diameter of the first roll. min Let D be the minimum diameter corresponding to the groove region. Due to the presence of the groove, D... min Reduce, thereby reducing the maximum diameter change value ΔD max Increase. The control module is based on the maximum diameter change value ΔD. max By determining the maximum limiting current, a larger permissible limiting current value can be obtained. Because the maximum limiting current allowed by the grinding machine control module is increased, a larger grinding current can be used during the grinding process, thereby increasing the amount of material removed per unit time and improving grinding efficiency.

[0029] In this embodiment, the groove, as the lowest point in the surface profile curve, is used in the calculation of the maximum diameter change value. This allows the grinding machine control module to obtain a maximum limiting current higher than that under normal operating conditions, thereby increasing the settable grinding current value and enabling stable grinding throughout the entire grinding process under higher current conditions. This embodiment alters the surface profile characteristics of the roll, changing the calculation basis of the maximum limiting current in the grinding machine control system. This allows the grinding machine control system to proactively increase the allowable grinding current, thus improving grinding efficiency without changing the grinding machine hardware.

[0030] In one embodiment, the step of grinding the first roll to obtain the second roll includes: S31: Perform reciprocating grinding on the reciprocating section of the first roll.

[0031] Specifically, the first roll includes a reciprocating section and a spacer section located on at least one side of the reciprocating section, the spacer section including a groove. Furthermore, the reciprocating grinding process is performed multiple times.

[0032] In one embodiment, the grinding current is 80~100A, and the transverse speed of the reciprocating grinding process is 100~300mm / min. In one reciprocating grinding process, the diameter variation of the reciprocating section is 0.2~0.3mm.

[0033] S32: The interval section of the first roll is smoothed and ground so that the diameter of the interval section is equal to the diameter of the reciprocating section, thus obtaining the second roll.

[0034] Specifically, the diameters of the rolls in the reciprocating section are basically the same. In the reciprocating section, the actual current of the grinding wheel is maintained as the grinding current. However, in the dressing grinding process, when the grinding wheel is located in the groove, since the diameter of the groove is lower than the overall diameter of the roll, the actual current is the no-load current. For example, when the grinding current is 80~100A and the transverse speed of the reciprocating grinding process is 100~300mm / min, the actual current of the grinding wheel in the groove is 5A and the transverse speed is 2500~3000mm / min.

[0035] Specifically, grinding machines typically have an automatic profile curve update function. After the grinding wheel completes one pass of grinding, that is, after the grinding wheel grinds from one end of the roll to the other end, and then from the other end of the roll to one end, the grinding machine will remeasure or calculate the current roll surface profile curve, and recalculate the maximum diameter change value ΔD based on the updated profile curve. max And the corresponding maximum limiting current. As material is gradually removed from the reciprocating section, the diameter of the reciprocating section gradually decreases, causing the difference between the maximum diameter of the roll and the minimum diameter of the groove region to gradually decrease, thus resulting in a change in the maximum diameter ΔD. maxAs the current gradually decreases, the maximum limiting current calculated by the grinding machine control system gradually decreases, thus reducing the allowable grinding current during the grinding process and affecting grinding efficiency.

[0036] Furthermore, in this embodiment, the second roll is divided into a reciprocating section and an interval section located on one side of the reciprocating section. The groove is located in the interval section, and the interval section is not leveled during multiple reciprocating grinding cycles in the reciprocating section. This allows the groove area to continuously participate in the calculation of the maximum diameter change value as the minimum diameter area in the roll surface profile curve, thereby maintaining a large maximum diameter change value ΔD over multiple reciprocating grinding cycles. max This allows the grinding machine control system to maintain a high maximum limiting current, enabling the reciprocating machining section to continuously grind under high grinding current conditions, thereby improving the material removal rate per unit time and the overall grinding efficiency.

[0037] Furthermore, after the reciprocating grinding process has completed a predetermined number of reciprocating grinding operations in the reciprocating section, step S32 is executed to perform a smoothing grinding process on the interval section, gradually removing the groove area and making the diameter of the interval section equal to the diameter of the reciprocating section, thereby obtaining a second roll with a consistent surface diameter. It should be understood that the length of the interval section is greater than the axial length of the groove, and the length of the interval section should be as small as possible to reduce the time required for the smoothing grinding process. Furthermore, the radius difference between the second roll and the first roll is greater than or equal to the depth of the groove, meaning the total grinding depth of the reciprocating grinding process should be greater than or equal to the depth of the groove.

[0038] In this embodiment, the groove continuously participates in the contour curve calculation during the main material removal stage of the reciprocating machining section, thereby delaying the decrease of the maximum limiting current and enabling the grinding machine to maintain a high grinding current during the critical material removal stage. Furthermore, this machining method can also reduce the frequent adjustments of grinding parameters caused by the frequent decrease of the maximum limiting current, improving the stability of the grinding process.

[0039] In this embodiment, the increased maximum allowable current limit of the grinding machine control system allows for the use of a larger grinding current during the grinding process, thereby increasing the material removal per unit time and improving grinding efficiency. During the grinding process, the groove region, as the lowest point in the contour curve, participates in the calculation of the maximum diameter change value, enabling the grinding machine control system to continuously maintain a high limit current setting, thus allowing stable grinding under high current conditions throughout the entire reciprocating machining section.

[0040] This embodiment increases the maximum diameter variation of the roll surface by pre-grooving grooves at the roll end, thereby enabling the grinding machine control system to increase the maximum limiting current setting value, thus breaking through the traditional grinding current limit, allowing the grinding process to operate stably under higher current conditions, improving material removal efficiency and shortening processing time.

[0041] Furthermore, the grinding method provided in this application embodiment also includes: S4: If the diameter of the second roll is greater than the preset diameter, the second roll is designated as the roll to be processed; if the diameter of the second roll is less than or equal to the preset diameter, the roll to be ground is designated as the target roll.

[0042] Specifically, after completing step S3, the surface diameter of the second roll is measured using the grinding machine's sensing module, and the measured roll diameter is compared with a preset diameter. The preset diameter is the target machining size of the roll. It is determined whether the diameter of the second roll is greater than the preset diameter. If the diameter is greater than the preset diameter, it indicates that the roll still has machining allowance and grinding needs to continue. At this time, the second roll is re-designated as the roll to be processed, and steps S1 to S3 are repeated, i.e., a groove is formed again at the end of the roll, and the surface contour curve is re-acquired. This allows the grinding machine control system to redetermine the maximum limiting current based on the new contour curve, ensuring that subsequent grinding processes can still be performed under a higher limiting current condition. When the diameter of the second roll is less than or equal to the preset diameter, it indicates that the roll diameter has reached the target machining size requirement. At this time, grinding is stopped, and the current roll is designated as the target roll.

[0043] Specifically, through the cyclic judgment and processing in steps S1 to S4, the roll can maintain a large surface profile diameter change value through the pre-made groove throughout the entire grinding cycle. This allows the grinding machine control system to maintain a high maximum limiting current in each processing stage, ensuring that the grinding process is always carried out under conditions of high material removal rate. Compared with traditional processes, the grinding method in this embodiment can improve the processing efficiency by approximately 35%.

[0044] In one embodiment, the grinding parameters further include at least one of the following: X-axis gain value, Y-axis gain value, and grinding wheel rotation cycle. The X-axis gain value controls the feed servo stiffness of the grinding process, enabling higher grinding current at larger diameter positions and preventing air cutting at smaller diameter positions. A larger X-axis gain value results in lower grinding current at smaller diameter positions and higher grinding current at larger diameter positions. The Y-axis gain value controls the traverse speed variation during grinding, reducing the impact of contour abrupt changes and protecting the grinding wheel during high-current, high-efficiency machining. A larger Z-axis gain value results in faster traverse speed at smaller diameter positions and slower traverse speed at larger diameter positions. The grinding wheel rotation cycle controls the rotational speed variation of the grinding wheel during grinding. When the grinding wheel rotation cycle is 0, the grinding wheel rotates at a constant speed. When the grinding wheel rotation cycle is 1, the grinding wheel's rotational speed gradually increases and then decreases throughout the operation.

[0045] In one embodiment, the X-axis gain value is 0.5~2, and the Y-axis gain value is 0.5~2. The grinding wheel rotation cycle is 1. When the grinding wheel rotation cycle is 1, it can break the frequency and possibility of resonance, and avoid the periodic vibration caused by resonance during long-term operation of the grinding wheel.

[0046] In one embodiment, a cracked roll is ground using a Herkules WS1100X9000CNC cylindrical grinding machine. Using conventional methods, i.e., directly grinding with the grinding machine, the roll diameter before grinding was 912.941 mm, processing started at 9:39 AM, and the diameter after grinding was 910.981 mm, with grinding completion at 5:17 PM, resulting in a grinding allowance of 1.96 mm and a processing time of 7 hours and 38 minutes (458 minutes). Using the grinding method of this embodiment, the roll diameter before grinding was 907.529 mm, processing started at 9:09 AM, and the diameter after grinding was 905.326 mm, with grinding completion at 2:01 PM, resulting in a grinding allowance of 2.203 mm and a processing time of 4 hours and 52 minutes (292 minutes). Compared with traditional processes, the processing efficiency improvement value of this application is (458-292) / 458=36.2%.

[0047] A second aspect of this application provides a grinding machine for a rolling mill roll, used to implement the grinding method provided in the first aspect of this application. The grinding machine includes a worktable, a grinding wheel, a sensing module, and a control module. The worktable is used to support the rolling mill roll. The grinding wheel is used to perform grinding processing on the rolling mill roll. The sensing module is used to acquire the surface profile curve of the rolling mill roll. The control module is used to determine the maximum limiting current based on the surface profile curve and control the operation of the grinding wheel based on grinding processing parameters, wherein the grinding processing parameters include a grinding current, which characterizes the maximum limiting current.

[0048] Specifically, the worktable drives the roll to rotate around its axis, creating relative motion between the roll and the grinding wheel, thus achieving grinding. The grinding wheel can move axially and radially along the roll, with the radial movement along the X-axis. The grinding wheel is 100mm wide. Under the control of the control module, the grinding wheel performs reciprocating grinding motion along the roll axis and feed or retract along the X-axis, thereby removing material from the roll. The sensing module detects the diameter data of each axial position of the roll and generates surface profile curves. The control module is connected to both the grinding wheel and the sensing module. It receives the roll surface profile curves collected by the sensing module, determines the maximum limiting current based on the surface profile curves, and controls the grinding wheel to move along the X-axis based on the grinding current.

[0049] This embodiment increases the maximum diameter variation of the roll surface by forming a groove on the roll end surface, thereby changing the surface profile curve of the roll. This allows the grinding machine control system to increase the maximum limiting current setting, thus breaking through the traditional grinding current limitation. This enables the grinding process to operate stably under higher current conditions, improving material removal efficiency and shortening processing time.

[0050] It should be noted that, in this document, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes that element. Furthermore, it should be noted that the scope of the methods and apparatuses in the embodiments of this application is not limited to performing functions in the order shown or discussed, but may also include performing functions substantially simultaneously or in the reverse order, depending on the functions involved. For example, the described methods may be performed in a different order than described, and various steps may be added, omitted, or combined. Additionally, features described with reference to certain examples may be combined in other examples.

[0051] The embodiments of this application have been described above with reference to the accompanying drawings. However, this application is not limited to the specific embodiments described above. The specific embodiments described above are merely illustrative and not restrictive. Those skilled in the art can make many other forms under the guidance of this application without departing from the spirit and scope of the claims, and all of these forms are within the protection scope of this application.

Claims

1. A grinding method for a roll characterized by, Includes the following steps: A groove is formed on the end face of the roll to be processed to obtain the first roll; Obtain the surface profile curve of the first roll; The first roll is ground based on the grinding parameters to obtain the second roll; wherein the grinding parameters include grinding current, which is used to characterize the maximum limiting current determined based on the surface profile curve.

2. The grinding method according to claim 1, characterized in that, The grinding parameters also include: At least one of X-axis gain value, Y-axis gain value, and grinding wheel rotation cycle, wherein the X-axis gain value is used to control the feed servo stiffness of the grinding process, the Y-axis gain value is used to control the traverse speed variation of the grinding process, and the grinding wheel rotation cycle is used to control the rotational speed variation of the grinding wheel during the grinding process.

3. The grinding method according to claim 1, characterized in that, The grinding method further includes: If the diameter of the second roll is larger than the preset diameter, the second roll is used as the roll to be processed. If the diameter of the second roll is less than or equal to the preset diameter, the roll being ground is determined to be the target roll.

4. The grinding method according to any one of claims 1 to 3, characterized in that, The step of grinding the first roll to obtain the second roll includes: The reciprocating section of the first roll is subjected to reciprocating grinding. The interval section of the first roll is smoothed and ground so that the diameter of the interval section is equal to the diameter of the reciprocating section, thus obtaining the second roll. The first roll includes the reciprocating section and the interval section located on at least one side of the reciprocating section.

5. The grinding method according to claim 4, characterized in that, The interval segment includes the groove; The radius difference between the second roll and the first roll is greater than or equal to the depth of the groove.

6. The grinding method according to claim 4, characterized in that, The reciprocating grinding process is performed multiple times. The transverse speed of the reciprocating grinding process is 100~300mm / min.

7. The grinding method according to claim 4, characterized in that, In the reciprocating grinding process, the diameter variation of the reciprocating section is 0.2~0.3mm; The grinding current is 80~100A.

8. The grinding method according to any one of claims 1 to 3, characterized in that, The depth of the groove is 0.2~0.5mm; The axial length of the groove is 200~300mm.

9. The grinding method according to any one of claims 1 to 3, characterized in that, The surface profile curve is used to characterize the change in the roll surface diameter of the first roll; The maximum limiting current is determined based on the maximum diameter change of the first roll surface.

10. A grinding machine for rolling mill rolls, characterized in that, For implementing the grinding method according to any one of claims 1 to 9, the grinding machine comprises: The worktable is used to support the rolling mill rolls; Grinding wheels are used for grinding rolls; The sensing module is used to acquire the surface profile curve of the roll; A control module is used to determine the maximum limiting current based on the surface profile curve and control the operation of the grinding wheel based on grinding processing parameters, wherein the grinding processing parameters include grinding current, which is used to characterize the maximum limiting current.

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