A control method for prolonging the life of a coiling machine arbor

Abstract

The application relates to a control method for prolonging the service life of a coiling machine mandrel and belongs to the technical field of rolling equipment control methods.The technical scheme of the application is as follows: the servo system of the coiler pressure adjustment is logarithmic, the servo output of the coiler servo in the downward direction is reduced in advance according to the tracking position of the strip steel, the short stroke function of the coiler is developed, and the coiler is controlled; the mandrel cooling water is opened when the steel coil just leaves the coiling machine mandrel, and a cooling water pipeline is additionally arranged behind the No.1 coiler; and the dry oil lubrication model is optimized, and the dry oil pipeline is completely opened.The beneficial effects of the application are as follows: the impact of the strip steel and the coiler on the mandrel is reduced by optimizing the servo control strategy of the coiler and adding the short stroke function of the coiler head, the cooling effect of the mandrel is improved by innovating the mandrel cooling water process control mode, the lubrication in place rate and the effective rate of the mandrel are improved by innovating the dry oil lubrication control method, and therefore the service life of the mandrel is prolonged.

Description

Technical Field

[0001] This invention relates to a control method for extending the life of a coiler mandrel, belonging to the technical field of rolling mill equipment control methods. Background Technology

[0002] The coiler is a critical quality control device in a hot-rolled strip production line, significantly impacting tension establishment and coil shape control. It is expensive, requires lengthy replacement times, and is a key maintenance focus for the hot-rolled production line. Extending the lifespan of the coiler mandrel and ensuring its optimal condition are essential for cost reduction and quality improvement. Key factors affecting mandrel lifespan include wear caused by external impacts, insufficient or untimely cooling, and lubrication failure. External impacts primarily occur from the initial stepping control of the strip entering the coiler's auxiliary coiling rollers until the rollers open after coiling. Due to the complex coiling process of the strip head on the mandrel, improper servo adjustment of the auxiliary coiling rollers can result in extremely high impacts on the mandrel, sometimes reaching 1300kN, causing significant damage.

[0003] Problems with Inadequate Mandrel Cooling: During the coiling process in a hot rolling production line, the mandrel is in prolonged contact with the high-temperature strip steel (over 700 degrees Celsius), resulting in a very high temperature rise. After the coil is unloaded, a short water-spraying cooling process occurs when the coiling rollers hold it together. The cooling water flows from the coiling rollers to the mandrel for further cooling until the next coil enters the coiler. In the high-efficiency production environment, insufficient cooling time prevents the mandrel from cooling properly, keeping it in a continuously high-temperature operating state. This causes changes in the rigidity of the mandrel's sector plate and its internal structure, making the surface prone to pitting or cracking, ultimately ending the mandrel's lifespan. Prolonged high temperatures also lead to another significant problem: the lubricating oil inside the mandrel can degrade or even solidify at high temperatures, causing blockages in the internal lubrication lines. Once blocked, unblocking is extremely difficult, necessitating the removal of the mandrel from the machine for maintenance.

[0004] Lubrication failure issue: Because the spindle operates at high temperatures, its internal dry oil lubrication system is no longer suitable for the environment. The typical dry oil lubrication system involves pressurizing and pumping oil into two separate oil lines every 10 minutes. When the pressure in the first line reaches 130 bar, the system switches to the second line, stopping when it reaches 130 bar and waiting 10 minutes before repeating the cycle. However, because only a small amount of dry oil is pumped into the lines each time, the dry oil in the spindle's lines is replaced too frequently. Under high temperatures, the dry oil deteriorates or even cakings, forcing the spindle to be taken out of service for repairs.

[0005] These problems will have a negative impact on the lifespan of the spindle, and innovative methods are urgently needed to solve them. Summary of the Invention

[0006] The purpose of this invention is to provide a control method for extending the life of a coiler mandrel. By optimizing the servo control strategy of the auxiliary coiling roller and adding a short-stroke function at the head of the auxiliary coiling roller, the impact of the strip and the auxiliary coiling roller on the mandrel is reduced. By innovating the mandrel cooling water process control method, the cooling effect of the mandrel is improved. By innovating the dry oil lubrication control method, the lubrication rate and efficiency of the mandrel are improved, thereby increasing the life of the mandrel and effectively solving the above-mentioned problems existing in the background art.

[0007] The technical solution of the present invention is: a control method for extending the life of a winding machine mandrel, comprising the following steps:

[0008] (1) Control of the auxiliary coiling roller: The auxiliary coiling roller pressure adjustment servo system is logarithmic to solve the resonance problem of the auxiliary coiling roller during the steel feeding process of the coiler; Based on the strip tracking position, the servo output of the auxiliary coiling roller in the downward direction is reduced in advance by prediction to reduce the impact force of the auxiliary coiling roller on the mandrel; The short stroke function of the auxiliary coiling roller is developed to determine the swinging time of the auxiliary coiling roller. Before the strip head arrives at the coiler, the auxiliary coiling roller waits at the set value + short stroke position. When the strip head arrives, it swings to the set position to avoid collision with the auxiliary coiling roller when waiting for steel.

[0009] (2) Mandrel cooling water control: turn on the mandrel cooling water when the steel coil just leaves the mandrel of the coiler, and add a cooling water line after the No. 1 auxiliary coiling roller;

[0010] (3) Control the dry oil lubrication system, optimize the dry oil lubrication model, and completely open the dry oil pipeline.

[0011] In step (1), the number of servo systems for adjusting the pressure of the auxiliary roll is increased, and a delay element is added to the pressure feedback calculation of the auxiliary roll. The delay time parameter is adjusted to change the phase of the fluctuation period and avoid coupling between the auxiliary roll body and the servo system period.

[0012] In step (1), based on the strip tracking position, when the strip head rotates to the bottom, the servo output of the auxiliary winding roller in the downward direction is reduced in advance to reduce the impact force of the auxiliary winding roller on the mandrel.

[0013] In step (1), the formula for calculating the timing of the auxiliary winding roller's insertion is as follows:

[0014] T = l / vt

[0015] Where l: the distance between the cold metal detector (CMD) and the auxiliary winding roller;

[0016] V: Speed ​​of the strip;

[0017] T: Margin time.

[0018] In step (2), an unloading trolley is provided below the coiler to unload the steel coil from the coiler by lateral movement; a displacement sensor is installed in the hydraulic cylinder of the unloading trolley to calculate when the unloading trolley has left the coiler mandrel, and the mandrel cooling water is turned on in advance and the mandrel is rotated to cool it.

[0019] In step (3), the original single loop of A-path followed by B-path, and then waiting for 5 minutes, is changed to multiple loops of A-path followed by B-path for 6 minutes, and then idle for 4 minutes.

[0020] The winding machine consists of a mandrel and three auxiliary winding rollers surrounding it. The opening and closing of the auxiliary winding rollers toward the mandrel is controlled by a hydraulic servo system.

[0021] The beneficial effects of this invention are: by optimizing the servo control strategy of the auxiliary winding roller and adding a short-stroke function at the head of the auxiliary winding roller, the impact of the strip and the auxiliary winding roller on the mandrel is reduced; by innovating the mandrel cooling water process control method, the cooling effect of the mandrel is improved; and by innovating the dry oil lubrication control method, the lubrication rate and efficiency of the mandrel are improved, thereby increasing the life of the mandrel. Attached Figure Description

[0022] Figure 1 This is a schematic diagram of the system structure of the present invention. Detailed Implementation

[0023] To make the purpose, technical solutions, and advantages of the invention's embodiments clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the embodiments described are only a small part of the embodiments of the present invention, not all of them. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the protection scope of the present invention.

[0024] A control method for extending the life of a winding machine spindle includes the following steps:

[0025] (1) Control of the auxiliary coiling roller: The auxiliary coiling roller pressure adjustment servo system is logarithmic to solve the resonance problem of the auxiliary coiling roller during the steel feeding process of the coiler; Based on the strip tracking position, the servo output of the auxiliary coiling roller in the downward direction is reduced in advance by prediction to reduce the impact force of the auxiliary coiling roller on the mandrel; The short stroke function of the auxiliary coiling roller is developed to determine the swinging time of the auxiliary coiling roller. Before the strip head arrives at the coiler, the auxiliary coiling roller waits at the set value + short stroke position. When the strip head arrives, it swings to the set position to avoid collision with the auxiliary coiling roller when waiting for steel.

[0026] (2) Mandrel cooling water control: turn on the mandrel cooling water when the steel coil just leaves the mandrel of the coiler, and add a cooling water line after the No. 1 auxiliary coiling roller;

[0027] (3) Control the dry oil lubrication system, optimize the dry oil lubrication model, and completely open the dry oil pipeline.

[0028] In step (1), the number of servo systems for adjusting the pressure of the auxiliary roll is increased, and a delay element is added to the pressure feedback calculation of the auxiliary roll. The delay time parameter is adjusted to change the phase of the fluctuation period and avoid coupling between the auxiliary roll body and the servo system period.

[0029] In step (1), based on the strip tracking position, when the strip head rotates to the bottom, the servo output of the auxiliary winding roller in the downward direction is reduced in advance to reduce the impact force of the auxiliary winding roller on the mandrel.

[0030] In step (1), the formula for calculating the timing of the auxiliary winding roller's insertion is as follows:

[0031] T = l / vt

[0032] Where l: the distance between the cold metal detector (CMD) and the auxiliary winding roller;

[0033] V: Speed ​​of the strip;

[0034] T: Margin time.

[0035] In step (2), an unloading trolley is provided below the coiler to unload the steel coil from the coiler by lateral movement; a displacement sensor is installed in the hydraulic cylinder of the unloading trolley to calculate when the unloading trolley has left the coiler mandrel, and the mandrel cooling water is turned on in advance and the mandrel is rotated to cool it.

[0036] In step (3), the original single loop of A-path followed by B-path, and then waiting for 5 minutes, is changed to multiple loops of A-path followed by B-path for 6 minutes, and then idle for 4 minutes.

[0037] The winding machine consists of a mandrel and three auxiliary winding rollers surrounding it. The opening and closing of the auxiliary winding rollers toward the mandrel is controlled by a hydraulic servo system.

[0038] In practical applications, the main factors affecting spindle life are external impact, cooling, and dry lubrication. By adjusting servo system parameters and reducing external forces, a series of methods are used to improve the spindle's operating conditions and extend its life. The control methods mainly include:

[0039] Auxiliary Roller Control Method: By adding a delay element to the auxiliary roller pressure feedback calculation, adjusting the delay time parameter can change the phase of the fluctuation cycle, solving the resonance problem in the auxiliary roller step control process during steel feeding at the coiler, and avoiding the coupling between the auxiliary roller body and the servo system cycle. Furthermore, based on the strip tracking position, when the strip head rotates downwards, the servo output in the downward direction of the auxiliary roller is reduced in advance, reducing the impact force of the auxiliary roller on the mandrel. By developing a short-stroke function for the auxiliary roller, the auxiliary roll waits at the set value + short stroke position before the strip head reaches the coiler, and then swings to the set position when the strip head arrives. This solves the problem of the mandrel collided with the auxiliary roller during steel waiting after the sector plate loosens in the later stages of its lifespan, accelerating deterioration. Auxiliary Roller Swinging Timing Calculation Formula:

[0040] T = l / vt

[0041] Where l: the distance between the cold metal detector (CMD) and the winding roller.

[0042] V: Through the speed of the strip steel

[0043] T: Margin time.

[0044] Mandrel cooling water control: A displacement sensor is installed inside the hydraulic cylinder of the unwinding trolley to calculate when the unwinding trolley has left the mandrel of the winding machine. The mandrel cooling water is activated in advance, and the mandrel is rotated for cooling. At this time, the auxiliary winding roller is not closed, allowing the mandrel to cool down rapidly. An additional cooling water line is installed after the No. 1 auxiliary winding roller to cool the mandrel after it is closed, preventing lubrication failure due to dried-out lubricating oil and restoring its material strength to prevent breakage.

[0045] Dry oil lubrication system control: The dry oil lubrication model has been optimized. The original single-cycle A-path followed by B-path, and then a 5-minute wait, has been changed to multiple cycles A-path followed by B-path, 6 minutes, and then a 4-minute idle period. This can completely open the dry oil pipeline in one go, avoiding the dry oil from failing to open the pipeline in a single cycle after the idle period. This prevents the dry oil from hardening due to prolonged heating, which would eventually lead to spindle lubrication failure and the end of its lifespan.

[0046] This invention solves the resonance problem of the auxiliary winding roller by avoiding the periodic coupling between the auxiliary winding roller body and the servo system, thus reducing pressure fluctuations. Based on the strip tracking position, the servo output in the downward direction of the auxiliary winding roller is reduced in stages, minimizing the impact force of the auxiliary winding roller on the mandrel. The material tracking system is optimized to ensure accurate positioning during auxiliary winding roller step control. A short-stroke function for the auxiliary winding roller is developed to address the problem of accelerated deterioration caused by collisions between the mandrel and the auxiliary winding roller after mandrel aging. The integral accumulation error of the PI controller is eliminated, making the servo input more targeted. The servo limit value in the opening direction of the auxiliary winding roller is increased to enhance the roller's movement speed and improve the set accuracy. The cooling water sequence between the mandrel and the auxiliary winding roller is optimized, and the mandrel is rotated for rapid cooling, preventing lubrication failure due to lubricating oil drying and restoring material strength to avoid breakage. Variable mandrel expansion force technology is developed to enhance the mandrel's expansion capacity.

[0047] The above description is merely a preferred embodiment of the present invention and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention are included within the scope of protection of the present invention.

Claims

1. A control method for extending the life of a winding machine mandrel, characterized in that... Includes the following steps: (1) Control of the auxiliary coiling roll: Add a delay element to the pressure feedback calculation of the auxiliary coiling roll and adjust the delay time parameter to change the phase of the fluctuation period, avoid the coupling between the auxiliary coiling roll body and the servo system period, and solve the resonance problem of the auxiliary coiling roll in the process of feeding steel in the coiler; According to the strip tracking position, reduce the servo output of the auxiliary coiling roll servo in the downward direction in advance by prediction, and reduce the impact force of the auxiliary coiling roll on the mandrel. Develop a short-stroke function for the helper roll to determine the timing of the helper roll's swing. Before the strip head reaches the coiler, the helper roll waits at the set value + short stroke position. When the strip head arrives, it swings to the set position to avoid collision between the mandrel and the helper roll when waiting for the strip. (2) Mandrel cooling water control: turn on the mandrel cooling water when the steel coil just leaves the mandrel of the coiler, and add a cooling water line after the No. 1 auxiliary coiling roller; (3) Control the dry oil lubrication system, optimize the dry oil lubrication model, and completely unblock the dry oil pipeline.

2. The control method for extending the life of a winding machine mandrel according to claim 1, characterized in that: In step (1), based on the strip tracking position, when the strip head rotates to the bottom, the servo output of the auxiliary winding roller in the downward direction is reduced in advance to reduce the impact force of the auxiliary winding roller on the mandrel.

3. The control method for extending the life of a winding machine mandrel according to claim 1, characterized in that: In step (1), the formula for calculating the timing of the auxiliary winding roller is as follows: ； Where l: the distance between the cold metal detector (CMD) and the auxiliary winding roller; V: Speed ​​of the strip; t: margin time.

4. The control method for extending the life of a winding machine mandrel according to claim 1, characterized in that: In step (2), an unloading trolley is provided below the coiler to unload the steel coil from the coiler by lateral movement; a displacement sensor is installed in the hydraulic cylinder of the unloading trolley to calculate when the unloading trolley has left the coiler mandrel, and the mandrel cooling water is turned on in advance and the mandrel is rotated to cool.

5. The control method for extending the life of a winding machine mandrel according to claim 1, characterized in that: In step (3), the original single loop of A-path followed by B-path, and then waiting for 5 minutes, is changed to multiple loops of A-path followed by B-path for 6 minutes, and then idle for 4 minutes.

6. The control method for extending the life of a winding machine mandrel according to claim 1, characterized in that: The winding machine consists of a mandrel and three auxiliary winding rollers surrounding it. The opening and closing of the auxiliary winding rollers toward the mandrel is controlled by a hydraulic servo system.

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