A method for detecting internal damage of a rubber roll of a stainless steel finished product unit and grinding repair

Abstract

This invention relates to a method for detecting and grinding repairing internal defects in rubber rollers of stainless steel finished product units. The method includes: S1, Pre-inspection by touch: Fixing the new rubber roller on the roller frame and maintaining low-speed rotation, with the operator wearing gloves touching to detect defects; S2, If a defect is detected, replacing the rubber coating; if no defect is detected, proceeding to step S3; S3, Using the rubber roller on the machine: After indentation defects appear on the strip, fixing the rubber roller on the roller frame and maintaining low-speed rotation, with the operator wearing gloves touching to detect the presence of internal defects / indentations. If present, proceeding to step S4; otherwise, replacing the rubber coating and reinstalling the roller; S4, After removal from the machine, grinding the roller surface to eliminate local deformation, followed by touching to check if the indentations have disappeared. If so, reinstalling the roller; otherwise, replacing the rubber coating. The advantages of this invention are: touch detection allows for pre-detection of defects during acceptance, significantly reducing the frequency of roller replacement; it also identifies hidden internal defects / indentations, resulting in a high success rate of grinding repair, avoiding blind replacement of new rollers, and reducing costs.

Description

Technical Field

[0001] This invention relates to the field of stainless steel cold rolling technology, specifically to a method for detecting and grinding repairing internal damage on rubber rollers of stainless steel finished product units. Background Technology

[0002] The stainless steel finishing mill is a key piece of equipment used in the post-cold rolling process of stainless steel. Its core function is to process stainless steel semi-finished products, which have undergone previous processes such as rolling, annealing, and pickling, into final products that meet customer requirements. The rollers in the stainless steel finishing mill largely use polyurethane-coated vulcanized rubber rollers. Under the continuous tension of the strip, periodic internal indentations easily appear on the roller surface at 1 / 4 of the width. These internal indentations cause very small deformations on the roller surface, which are invisible to the naked eye, but directly lead to defects on the strip surface, thus reducing product quality. Replacing the rubber coating directly after defects occur increases equipment maintenance costs.

[0003] Currently, the industry generally believes that internal indentations on rubber rollers are caused by uneven roller surface hardness or external damage. However, the core cause is that during the polyurethane roller casting process, incomplete air removal leads to closed air bubbles within the rubber layer. During operation, the roller is subjected to tension and high temperatures, causing plastic indentation deformation in the bubble areas and forming internal indentations, which then leave periodic marks on the strip. Currently, during the acceptance phase, rubber rollers are typically only measured for external dimensions and surface hardness, failing to detect internal air bubbles and potential internal indentations. This results in the inability to detect internal indentations before new rollers are installed, leading to frequent recurrence of these marks after use. Furthermore, the common approach for indented rollers is to replace the entire roller, but this method results in long downtime, high spare parts costs, and even attempts at grinding often fail due to improper timing or incomplete stress release, sometimes even rendering the roller unusable.

[0004] Therefore, further improvements are needed. Summary of the Invention

[0005] The technical problem to be solved by the present invention is to provide a method for detecting and grinding repairing internal damage and indentations on stainless steel finished machine rubber rollers, which is capable of detecting and repairing internal damage and indentations on rubber rollers, in light of the above-mentioned existing technology.

[0006] The technical solution adopted by this invention to solve the above-mentioned technical problems is as follows: A method for detecting and grinding repairing internal damage to the rubber rollers of a stainless steel finished product unit, characterized by the following steps:

[0007] S1. Touch pre-inspection: The bearings at both ends of the new rubber roller are mounted on the roller frame, and the rubber roller is driven to rotate at a low speed by a manual disc. The operator wears gloves with low friction and places his palm on the roller surface to slide smoothly and continuously along the axis, thereby detecting defects such as shallow bubbles, depressions or protrusions.

[0008] S2. If no abnormal defects are detected, proceed to step S3. If a defect is detected by touch, replace the rubber coating layer of the rubber roller and proceed to step S1 and before step S2. If a defect is still detected, repeat the above steps. If no defect is detected, proceed to S3.

[0009] S3. If the strip does not show any indentation defects, the rubber roller can continue to be used. If the strip shows indentation defects, the bearings at both ends of the rubber roller are mounted on the roller frame, and the rubber roller is rotated at a low speed by a manual disc. The operator wears gloves with low friction and places his palm on the roller surface to slide smoothly and continuously along the axis to determine whether there are internal damage indentations on the surface of the rubber roller. If so, proceed to step S4. If not, replace the rubber coating layer of the rubber roller. After the replacement rubber roller is found to have eliminated the defects, it can be put back into use. Otherwise, return to the above step of replacing the rubber coating layer.

[0010] S4. Grind the surface of the rubber roller after it comes off the machine to eliminate local deformation caused by deep air bubbles. Then, the operator wears gloves with low friction to check whether the indentation has been eliminated. If it has, it can be put back on the machine for use. If not, the rubber coating layer of the rubber roller is replaced until the defect is eliminated before it can be put back on the machine for use.

[0011] For ease of inspection, preferably, the linear rotation speed of the manual disc in steps S1 and S3 is 5 m / min to 10 m / min. Specifically, the linear rotation speed of the manual disc mounted on the roller frame needs to be maintained between 5 m / min and 10 m / min. When the linear rotation speed of the manual disc is lower than 5 m / min, the rubber roller rotates too slowly, resulting in low inspection efficiency for the operator; when the linear rotation speed of the manual disc is higher than 10 m / min, the rubber roller rotates too fast, affecting the accuracy of the operator's defect judgment.

[0012] For better identification, it is preferable that the gloves worn by the operator in steps S1, S3, and S4 are yarn gloves. Wearing yarn gloves can effectively reduce the frictional resistance between the palm and the surface of the rubber roller, and allow the palm to slide continuously, smoothly, and without obstruction on the rotating roller surface. This avoids the palm getting stuck, jumping, or interruption of the detection action due to excessive friction, thereby ensuring the continuous identification and stable detection of subtle defects such as shallow bubbles, soft spots, and local elasticity differences on the roller surface, and improving the accuracy and reliability of internal damage indentation detection.

[0013] To achieve precise defect elimination, preferably, the grinding position in step S4 is at 1 / 4 of the width from the end face of the rubber roller. Since the polyurethane rubber roller is formed by casting and vulcanization, incomplete air removal during the casting process can create tiny closed air bubbles within the rubber layer. Under the tension and high temperature during machine operation, internal indentations mainly appear at the 1 / 4 stress position from the end face of the rubber roller. At this point, the grinding wheel of the grinding machine can concentrate on grinding at this 1 / 4 width position from the end face of the rubber roller, thus better eliminating the indentation defects.

[0014] Furthermore, the grinding time in step S4 is within 8 hours after the rubber roller is removed from the machine. During the 8 hours after the rubber roller is removed from the machine, the rubber coating layer is not yet fully cooled and set, and the internal stress is not fully released. Under these conditions, the success rate of repairing internal damage indentations is higher.

[0015] Furthermore, the rubber rollers include anti-wrinkle rollers for leveling machines, exit guide rollers, inlet guide rollers for rewinding units, and exit guide rollers for winding, all operating under high tension conditions. Among these, the stainless steel finishing unit includes anti-wrinkle rollers for leveling machines, exit guide rollers, inlet guide rollers for rewinding units, and exit guide rollers for winding, all of which exhibit the same problem of internal damage and indentations. The aforementioned methods for detecting internal damage and grinding repair can be applied to anti-wrinkle rollers and guide rollers used under these high tension conditions.

[0016] Compared with the prior art, the advantages of the present invention are as follows:

[0017] 1. This invention reveals the true cause of internal damage and indentation on rubber rollers. Operators can detect shallow bubbles, soft spots, or local elasticity differences in new rubber rollers in advance by wearing gloves and touching them. The rubber coating can be replaced accordingly, thereby significantly reducing the frequency of roller replacement and downtime, and reducing equipment maintenance costs.

[0018] 2. When marks appear on the strip steel, operators wearing gloves can touch and inspect the surface of the rubber roller to identify hidden internal damage marks. These marks can then be repaired by grinding within a specified time after the roller leaves the machine. This method boasts a high success rate, extends the service life of the rubber roller, improves product qualification rates, avoids unnecessary replacement of rollers, and reduces costs. Furthermore, this internal damage detection and grinding repair method is highly versatile and can be adapted to rubber rollers in various stainless steel finishing units. Attached Figure Description

[0019] Figure 1 This is a partial cross-sectional view of the rubber roller in an embodiment of the present invention (showing bubbles and protrusions);

[0020] Figure 2 This is a partial cross-sectional view of the rubber roller in an embodiment of the present invention (showing bubbles, depressions, and protrusions).

[0021] Figure 3 This is a cross-sectional schematic diagram of the rubber roller in an embodiment of the present invention (showing the grinding position);

[0022] Figure 4 This is a schematic flowchart of the internal damage detection and grinding repair method in an embodiment of the present invention.

[0023] In the diagram: 1. Rubber roller; 11. Rubber coating layer; 12. Bearing; A. Air bubble; B. Protrusion; C. Depression. Detailed Implementation

[0024] The present invention will be further described in detail below with reference to the accompanying drawings and embodiments.

[0025] like Figure 1 and 2 As shown, the rubber roller 1 in this embodiment can be a leveling machine anti-wrinkle roller, an exit guide roller, an inlet guide roller of a rewinding unit, and a winding exit guide roller in a stainless steel finished product unit. This embodiment takes the exit guide roller as an example. The exit guide roller is a polyurethane rubber roller 1 and is formed by casting and vulcanization. Due to incomplete air removal during the casting process, tiny closed air bubbles A will be formed inside the rubber layer. When the rubber roller 1 is put into the operation of the unit, it will be subjected to tension and high temperature, and the rubber in the area of ​​air bubble A will undergo plastic depression C or bulge B deformation, which will form internal damage indentation and periodic marks on the strip steel. At this time, the produced products will be unqualified.

[0026] Therefore, refer to Figure 3 and Figure 4 This embodiment proposes a method for detecting and grinding repairing internal damage to the rubber roller 1 of a stainless steel finished product unit, including the following steps:

[0027] S1. Touch Pre-inspection: The bearings 12 at both ends of the new rubber roller 1 are mounted on the roller frame, and the rubber roller 1 is driven to rotate at a low speed by a manual disc. The operator wears gloves with low friction and places his palm on the roller surface to slide smoothly and continuously along the axis, thereby detecting defects such as shallow bubbles A, depressions C or protrusions B.

[0028] S2. If no abnormal defects are detected, proceed to step S3. If a defect is detected by touch, replace the rubber coating layer 11 of the rubber roller 1, and proceed to step S1 and before step S2. If a defect is still detected, repeat the above steps. If no defect is detected, proceed to S3.

[0029] S3. If the strip does not show any indentation defects, the rubber roller 1 can continue to be used. If the strip shows indentation defects, the bearings 12 at both ends of the rubber roller 1 are mounted on the roller frame, and the rubber roller 1 is rotated at a low speed by a manual disc. The operator wears gloves with low friction and places his palm on the roller surface to slide smoothly and continuously in the axial direction to determine whether there are internal damage indentations on the surface of the rubber roller 1. If so, proceed to step S4. If not, replace the rubber coating layer 11 of the rubber roller 1. After the replacement rubber roller 1 is found to have eliminated the defects, it can be put back into use. Otherwise, return to the above step of replacing the rubber coating layer 11.

[0030] S4. Grind the surface of the rubber roller 1 after it comes off the machine to eliminate the local deformation caused by deep air bubbles A. Then, the operator, wearing low-friction gloves, checks whether the indentation has been eliminated. If so, it is reused on the machine; if not, the rubber coating layer 11 of the rubber roller 1 is replaced until the defect is eliminated before it can be reused on the machine. (Refer to...) Figure 3 The internal indentations mainly appear at the 1 / 4 stress position from the end face of the rubber roller 1. After placing the rubber roller 1 on the grinding machine, control the grinding wheel to rotate at a low speed. At this time, the grinding wheel can concentrate on grinding the 1 / 4 width position from the end face of the rubber roller 1. During the grinding process, coolant is sprayed evenly, and the indentation area is checked by touch. When no indentation is detected, the surface of the rubber roller 1 can be finely ground until the surface roughness of the rubber roller 1 reaches the standard of Ra6.3. Then it can be removed from the grinding machine and reused. The reason why the operator chooses to perform grinding within 8 hours after the machine is that within 8 hours after the rubber roller 1 is removed from the machine, the rubber coating layer 11 is not completely cooled and shaped, and the internal stress is not fully released. The success rate of repairing internal indentations is higher in this state. In this embodiment, the preferred grinding time is 4 hours after the machine is removed.

[0031] Furthermore, it should be noted that in steps S1, S3, and S4, the operator wears low-cost, low-friction yarn gloves for hand contact inspection. Wearing yarn gloves effectively reduces the frictional resistance between the palm and the surface of the rubber roller 1, allowing the palm to slide continuously, smoothly, and without obstruction on the rotating roller surface. This prevents the palm from getting stuck, jumping, or the inspection action from being interrupted due to excessive friction, thus ensuring continuous identification and stable detection of subtle defects such as shallow bubbles A, depressions C, or protrusions B on the roller surface, improving the accuracy and reliability of internal damage indentation detection. Simultaneously, during the inspection process, the rotational linear speed of the manual disc mounted on the roller frame needs to be maintained between 5 m / min and 10 m / min. When the rotational linear speed of the manual disc is below 5 m / min, the rubber roller 1 rotates too slowly, resulting in low inspection efficiency for the operator; when the rotational linear speed of the manual disc is above 10 m / min, the rubber roller 1 rotates too fast, affecting the accuracy of the operator's defect judgment. Therefore, in this embodiment, the preferred linear speed of the rubber roller 1 is 8 m / min, which can simultaneously ensure both the accuracy and efficiency of the detection.

Claims

1. A method for detecting and grinding repairing internal damage to rubber rollers in stainless steel finished product units: characterized in that: Includes the following steps: S1. Touch pre-inspection: The bearings (12) at both ends of the new rubber roller (1) are mounted on the roller frame, and the rubber roller (1) is driven by a manual disc to maintain a low speed rotation. The operator wears gloves with low friction and places his palm on the roller surface to slide smoothly and continuously in the axial direction, thereby detecting defects such as shallow bubbles (A), depressions (C) or protrusions (B). S2. If no abnormal defects are detected, proceed to step S3. If a defect is detected by touch, replace the rubber coating layer (11) of the rubber roller (1) and proceed to step S1 and before step S2. If a defect is still detected, repeat the above steps. If no defect is detected, proceed to S3. S3. Use the rubber roller (1) on the machine. If the strip does not have an indentation defect, it can continue to be used on the machine. If the strip has an indentation defect, place the bearings (12) at both ends of the rubber roller (1) on the roller frame and drive the rubber roller (1) to rotate at a low speed by manually rotating it. The operator wears gloves with low friction and places his palm on the roller surface to slide smoothly and continuously in the axial direction to determine whether there is an internal damage indentation on the surface of the rubber roller (1). If yes, proceed to step S4. If no, replace the rubber coating layer (11) of the rubber roller (1). After the replacement rubber roller (1) is detected to have eliminated the defect, it can be put back on the machine. Otherwise, return to the above step of replacing the rubber coating layer (11). S4. Grind the roller surface of the rubber roller (1) after it is removed from the machine to eliminate the local deformation caused by deep air bubbles (A). Then, the operator wears gloves with low friction to check whether the indentation has been eliminated. If it is, it can be put back on the machine for use. If not, the rubber coating layer (11) of the rubber roller (1) is replaced until the defect is eliminated and it can be put back on the machine for use.

2. The method for detecting and grinding repairing internal damage to the rubber rollers of a stainless steel finished product unit as described in claim 1, characterized in that: In steps S1 and S3, the linear speed of the manual disc rotation is 5 m / min to 10 m / min.

3. The method for detecting and grinding repairing internal damage to the rubber rollers of a stainless steel finished product unit as described in claim 1, characterized in that: The gloves worn by the operators in steps S1, S3 and S4 are yarn gloves.

4. The method for detecting and grinding repairing internal damage to the rubber rollers of a stainless steel finished product unit as described in claim 3, characterized in that: The grinding position in step S4 is 1 / 4 of the width from the end face of the rubber roller (1).

5. The method for detecting and grinding repairing internal damage to the rubber rollers of a stainless steel finished product unit as described in claim 4, characterized in that: The grinding time in step S4 is within 8 hours after the rubber roller (1) is removed from the machine.

6. The method for detecting and grinding repairing internal damage to the rubber rollers of a stainless steel finished product unit as described in claim 5, characterized in that: The rubber rollers (1) include anti-wrinkle rollers for leveling machines, exit guide rollers, inlet guide rollers for rewinding units, and exit guide rollers for winding, etc., which are used under high tension conditions.

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