Abstract: The uncoiling requirements of hot-rolled coil boxes are extremely stringent, demanding high control precision. Even minor issues can lead to steel accumulation. This paper describes a method that utilizes HMD (Heated Depository Machine) detection signals combined with accurate coil diameter calculations to ensure the normal operation of the uncoiling arm. Intelligent self-learning libraries are used to automatically adjust control parameters, guaranteeing normal equipment operation and optimal coil shape. This technology has significant reference and application value for the control design of hot-rolled coil boxes. Keywords: Strip steel tracking tail positioning [b][align=center]Intelligence controller design and application of the peeling system about hot coil box Li Ying[/align][/b] Abstract: The hot coil box has a very high standard for control. If we have trouble, it is easy to pile steel. This paper designs the speed matching by exact calculation according to the measurement result of HMD. We design the control data change automation by intelligence database. So the equipment runs normally and the coil shape is good. The technology has important value for the coil box design and application of hot steel making. Keywords: Strip steel monitor Tail control 1. Brief description The hot coil box of Laiwu Steel's 1500mm rolling mill is an intermediate device in the rolling process, which has the function of conveying hot coil steel directly for continuous rolling. The intermediate billet begins coiling while still in the roughing mill. The hot coil box transfers the billet from the roughing mill at high speed, then uncoils it at low speed into the finishing mill. During the coiling process, the hot coil box reduces the surface area of ​​the intermediate billet affected by heat radiation, ensuring that the uncoiled intermediate billet has the same temperature as when it was coiled, thus maintaining temperature and shortening the roller table length. The strip steel is coiled and then uncoiled in the hot coil box, reducing the temperature difference between the head and tail of the strip, thereby improving the uniformity of the product material. The coiling setup includes: an inlet guide chute, strip forming rolls, an uncoiler, and a 1B idler frame. The uncoiling device includes: No. 2 and No. 3 idler frames for uncoiling, retracting the tail pin, and a pinch roll in a concealed position. The uncoiler arm control is extremely precise; even slight misalignment can easily lead to steel accumulation, making its precise control and positioning exceptionally important. 2. Control System The hot coil box can operate in either a straight-through mode or a coiling-in mode. Interference should be prevented in any operating mode, as instrument malfunction and single-action operation control can lead to mechanical failure. All position control loops must have emergency safety devices that can be activated in operating modes. 3. Design of the Uncoiling Arm Controller 3.1 The hot coil box for strip tracking uses hot metal detectors to detect the head and tail of the strip and whether the coil is in the hot coil box. A speed delay compensation is used to form additional strip tracking points. The positions of the hot metal detectors are shown in Figure 1: [align=center] Figure 1 Schematic diagram of hot metal detectors and their positions[/align] The symbols in the figure have the following meanings: (HMD = Hot Metal Detector) Coil box (hot coil box) 15m HMD (HMD1), On indicates the strip has arrived at the hot coil box, Off indicates it is approaching the tail. Coil box Entry (hot coil box entrance) HMD (HMD2) provides accurate head and tail tracking points for coil diameter calculation and braking. Cradle Roll No.1 (No. 1 idler roller) HMD (HMD3) indicates a coil is in the coiling area. A tracking signal is also generated, which is used to calculate and determine the location of the strip roll on idler roller No. 1 using the adjacent HMD signal and the roll diameter. Cradle Roll No. 2/3 (Idler Roll No. 2/3) HMD (HMD4) indicates that the strip or roll is in the uncoiling area, and is combined with the adjacent HMD signal to determine the position of the roll. Holdback Roll (HMD5) indicates that a roll being transferred is at the holdback roll. Pinch Roll (HMD6) indicates that the strip is in the pinch straightening roll. 3.2 Calculation of coil diameter The following formula is used to calculate the coil diameter (mm): Coil diameter (mm) = SQRT (((1+% air)X lengthX thickness) / (π/4)+ D hole 2) Here, SQRT represents the square root, the length (mm) comes from the calculated value of the No.1 idler roller tachometer, the thickness (mm) is the thickness of the intermediate billet, and % air is the gap between coils (the default is 3%=0.03, which can be adjusted in the human machine interface settings screen). D hole (mm) is the assumed coil eye diameter, the default value is 650mm (which can be adjusted in the controller). 3.3 Tail positioning is achieved by controlling the tail positioning based on the coil diameter calculation and the HMD signal. Once the tail positioning is completed, the hot coil box control switches from the start of coiling to the uncoiling function [1]. In this way, the uncoiling arm can automatically uncoil according to the program, so that the steel coil can automatically complete the uncoiling. The automatic uncoiling process is shown in Figure 2: [align=center] Figure 2: Automatic uncoiling mode of hot coil box[/align] 3.4 Tail stop control When HMD1 is off, and after the calculated speed compensation delay, CMSR (main coil speed) decelerates from the running speed to the stable speed of 1.5 m/s² (which can be adjusted in the controller). Thus, the reference value at the stable speed is about 0.5 m/s. When the tail passes through HMD2 at a stable speed, position control starts [2] until the tail finally stops. Before reaching a speed below 0.5 m/s, the highest deceleration rate is 1.5 m/s² (which can be adjusted in the PLC program), and then the highest deceleration rate is adjusted to 0.25 m/s² (which can be adjusted in the controller). Adjust the position control, stable speed and deceleration rate so that all coil specifications have a constant tail position and stable coil support during the stopping sequence. 3.5 Calculation of tail stop length When the tail of the intermediate billet passes through HMD2, calculate the length of the billet to be coiled. The length and stable speed of the entire tail stop make the deceleration mode of the coiling device generated. The operator of the hot coil box can adjust the tail stop position using the tail offset value obtained from the HMI setting screen. The offset value is directly added to the total tail length. 3.6 Uncoiling arm working mode There are three main working modes of the uncoiling arm: automatic simulation and manual. The manual mode is used when the signal or external equipment affects the movement of the uncoiling arm. In this way, the steel stacking can be avoided in the manual mode, which is conducive to the smooth production. 3.7 Speed ​​control of the uncoiling device [3] The uncoiling device moves at a fast speed of 20 o / second until it approaches the coil wall. The uncoiling device drops to 50% of the fast speed, runs for 1 second to contact the coil, and then resumes the fast speed until it reaches the deceleration point of the mechanical stop block. 4. Self-learning calculation function For the control parameters, a database is established. This function performs self-learning calculation on the parameters in the database and determines different self-learning coefficients according to the steel grade, plate thickness, and plate width. The self-learning algorithm uses exponential smoothing: β is the model coefficient to be learned. A self-learning table is used in the computer for this purpose. The coefficient stored in the self-learning table during the rolling of the nth steel is called β. When setting the parameters for the nth steel, the model will retrieve this value from the self-learning table. After the nth steel enters the finishing mill, the measured value of this coefficient can be calculated using actual rolling force, temperature, thickness, etc. If there is a difference between β and β, it indicates an error in the setting. Therefore, this new information is used to recursively correct (learn) the parameter, and the value is returned to the self-learning table (using β as a substitute) for use in the calculation of the (n+1)th steel (i.e., the next support steel). 5. Conclusion Since the system adopted intelligent uncoiling arm control, the equipment has operated well since its commissioning, with very few instances of steel piling up. The system is stable and reliable, with a low failure rate, creating significant economic benefits. References: [1] Chen Shouren. Engineering Inspection Technology. Beijing: Central Radio and Television University Press, 1996. [2] Wang Youming, Lu Shouli, Wei Guang. Controlled Rolling. Beijing: Metallurgical Industry Press, 1986. [3] Yu Shilin et al. Electrical Drive Automation Technology Handbook. Beijing: Machinery Industry Press, 1992.