A control method for a coiling pinch roll with a magnetic scale fault protection function

Abstract

The present invention relates to a coiling helping roll control method with magnetic scale fault protection function, belonging to the technical field of rolling equipment. The method specifically includes: S1: Reading the magnetic scale data of the helping roll by using an optimized data reading method; S2: Conducting effective value detection according to the read magnetic scale data. When the magnetic scale data is within 10 - 2000 mm, the current magnetic scale data is read, otherwise the previous data is locked; When the head of the strip passes the hot detector in the coiler, the effective value of the magnetic scale data is judged in real time. If the fault state lasts for more than 50 ms, the magnetic scale fault locking state is entered; S3: After entering the magnetic scale fault locking state, corresponding control processing is carried out according to the position where the head of the strip is located. The present invention solves the problem of unstable automatic control of the position of the coiling helping roll of the coiler.

Description

Technical Field

[0001] The present invention belongs to the technical field of rolling equipment and relates to a coiling assisting roll control method with a magnetic scale fault protection function. Background Art

[0002] The hot continuous rolling coiler is a core equipment of the rolling line, installed behind the laminar cooling section, and is used to wind the finished strip steel rolled by the finishing mill into a steel coil. The coiler has three assisting rolls, whose function is to guide the head of the strip to be bent and wound tightly on the mandrel. The roll gap between the assisting roll and the mandrel is adjustable, and the assisting roll has a hydraulic automatic stepping control function (AJC). The actual value of the roll gap of the assisting roll plays a key role in the position automatic control of this function. The position automatic control is the basic control function of the radial movement of the assisting roll. At the beginning of the skip, the hydraulic servo system will switch from the pressure control mode to the position control mode, and when the strip head passes through the assisting roll, it will switch back from the position control mode to the pressure control mode.

[0003] The hydraulic screw down position control system is based on the given reference value of the hydraulic cylinder position and the real-time measurement signal of the hydraulic cylinder position from the magnetic scale, and then converts it into a pressure signal. It adopts a control algorithm combining feedback control (PID) and feedforward control to generate a control signal for driving the servo valve, so that the hydraulic screw down cylinder can act quickly and accurately, realizing the closed-loop regulation of the position of the screw down cylinder. Since the magnetic scale is installed at a position on the assisting roll hydraulic cylinder where there is a large amount of water vapor and severe jitter, the magnetic scale has an occasional jump, especially in the stage of biting and impacting at the head of the coiling process, which is likely to cause the roll gap to jump, resulting in coiling tension loss and scrap steel. Therefore, there is an urgent need for a method to solve the stability problem of the position automatic control of the coiling assisting roll of the coiler. Summary of the Invention

[0004] In view of this, the purpose of the present invention is to provide a coiling assisting roll control method with a magnetic scale fault protection function, to solve the problem of coiling tension loss and scrap steel caused by the occasional jump of the magnetic scale value of the coiling assisting roll in the traditional coiler's position automatic control, and to realize the position automatic control of the assisting roll.

[0005] To achieve the above purpose, the present invention provides the following technical solutions:

[0006] A coiling assisting roll control method with a magnetic scale fault protection function specifically includes the following steps:

[0007] S1: Read the magnetic scale data of the assisting roll by using an optimized data reading method;

[0008] S2: Perform effective value detection according to the read magnetic scale data to determine whether to enter the magnetic scale fault locking state;

[0009] S3: When entering the magnetic scale fault locking state, perform corresponding control processing according to the position where the strip head is located.

[0010] Further, in step S1, the optimized data reading method is as follows: directly read the original double-integer pulse data of the magnetic scale, convert it into a floating-point type, and then multiply it by the magnetic scale resolution.

[0011] Further, in step S2, the effective value detection specifically includes: when the magnetic scale data is within 10 - 2000 mm, read the current magnetic scale data; otherwise, lock the previous data.

[0012] Further, in step S2, determining whether to enter the magnetic scale fault locking state specifically includes: when the head of the strip passes the hot detector in the coiler, continuously judge the effective value of the magnetic scale data. If the fault state lasts for more than 50 ms, enter the magnetic scale fault locking state.

[0013] Further, in step S3, after entering the magnetic scale fault locking state, perform corresponding control processing according to the position of the strip head, which specifically includes the following three processing methods:

[0014] (1) Before the head of the strip enters the coiling roll, lock the position and keep it still;

[0015] (2) After the head of the strip enters the coiling roll, lower the pressure ring of this coiling roll until the pressing is completed;

[0016] (3) After the pressing is completed, turn on the open-loop negative current until the strip is ejected from the coiler. After the strip is ejected from the coiler, if the magnetic scale data returns to normal, cancel the magnetic scale fault locking state and return to the normal state.

[0017] The beneficial effects of the present invention are as follows: The present invention adds the detection of the effective value of the magnetic scale of the coiling roll, locks when it exceeds the effective value range, and performs corresponding control according to the position of the strip head; effectively avoids coiling tension loss and scrap caused by magnetic scale faults, and solves the instability problem of the automatic control of the position of the coiling roll of the coiler compared with the control system before optimization.

[0018] Other advantages, objects and features of the present invention will be described to some extent in the following specification, and to some extent, will be obvious to those skilled in the art based on the study of the following text, or can be taught from the practice of the present invention. The objects and other advantages of the present invention can be realized and obtained through the following specification. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to make the objects, technical solutions and advantages of the present invention clearer, the present invention will be described in detail preferably with reference to the accompanying drawings, where:

[0020] Figure 1 is a flowchart of the control method for the coiling roll with magnetic scale fault protection function of the present invention;

[0021] Figure 2 Schematic diagram of the optimized magnetic scale data reading method structure

[0022] Figure 3 Schematic diagram of the magnetic scale effective value detection structure

[0023] Figure 4 Schematic diagram of the function structure of the magnetic scale fault protection against scrap steel during steel passing Specific implementation mode

[0024] The following uses specific examples to illustrate the implementation mode of the present invention. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification. The present invention can also be implemented or applied through other different specific implementation modes. Various details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of the present invention. It should be noted that the diagrams provided in the following embodiments only illustrate the basic concept of the present invention in a schematic manner. Without conflict, the following embodiments and the features in the embodiments can be combined with each other.

[0025] Please refer to Figures 1 to 4 , Figure 1 which is the flow chart of the coiling helping roll control method with the magnetic scale fault protection function of the present invention. This method first optimizes the magnetic scale data reading method of the helping roll. The original magnetic scale data was read through the data converted by the program block. This method has defects. When an external power supply fault or a fault of the magnetic scale itself occurs, a pulse needs to be sent to the program block for resetting in order to read the displacement data normally. This increases the fault time of the magnetic scale data. Now it is changed to directly read the original double integer pulse data of the magnetic scale, and multiply it by the magnetic scale resolution (0.002) after converting it to a real type to obtain it. This data does not require resetting the program block.

[0026] After reading the magnetic scale data, effective value detection (10, 2000) is performed. When the magnetic scale data is within 10 - 2000 mm, the current magnetic scale data is read, otherwise the previous data is locked. This function can ensure position locking when the magnetic scale jumps. When the head passes through the internal heat detector in the coiler, the effective value of the magnetic scale is judged in real time. If the fault state exceeds 50 ms, it enters the magnetic scale fault locking state, and the magnetic scale fault alarm information pops up on the screen. At the same time, the following three treatments are carried out:

[0027] (1) The position is locked and does not move before the head enters the helping roll.

[0028] (2) After the head enters the helping roll, the helping roll performs pressure ring pressing until the pressing is completed.

[0029] (3) After the pressing is completed, the open-loop negative current is turned on until the coiling throws off the steel. After the coiling throws off the steel, if the magnetic scale data returns to normal, the magnetic scale fault locking state is cancelled and the normal state is restored.

[0030] By adding the above control, the magnetic scale fault protection function of the coiling roll is realized.

[0031] Such as Figure 2 As shown, after the mechanical number of the on-site sensor read by this program block is converted into double-integer pulse data, it is multiplied by 0.002 after the real-type conversion of block No. 32 to obtain the feedback data of the WR1 measurement result, optimizing the magnetic scale data reading method, and this data does not need to reset the AENC block.

[0032] Such as Figure 3 As shown, Figure 3 (a) When the fluctuation range of the magnetic scale data is within 10 - 2000, the output of the NOR block is 1, and the NSW block executes the actual magnetic scale data; conversely, when the magnetic scale data exceeds the range of 10 - 2000, the NSW block locks the previous data; Figure 3 (b) It shows that when the magnetic scale fails for more than 50 ms, the output of block No. 6 is 1. When the head of the strip passes the hot detector in the coiler, blocks No. 10 and No. 14 execute the alarm and lock the data, and after the coiling is completed, it is reset by block No. 9.

[0033] Such as Figure 4 As shown, Figures 2 to 3 All calculations and scans are presented by this block, adding a function of preventing scrap steel for magnetic scale fault passing of steel: real-time judging the effective value of the magnetic scale, locking the magnetic scale fault state when the fault state exceeds 50 ms, and at the same time correctly handling the current position of the strip head.

[0034] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit them. Although the present invention has been described in detail with reference to the preferred embodiments, those of ordinary skill in the art should understand that the technical solutions of the present invention can be modified or equivalently replaced without departing from the purpose and scope of the present technical solution, and they should all be covered within the scope of the claims of the present invention.

Claims

1. A coiling assisting roll control method with a magnetic scale fault protection function, characterized in that The method specifically includes the following steps: S1: Read the data of the coiling roll magnetic scale by using an optimized data reading method. Specifically, directly read the original double-integer pulse data of the magnetic scale, convert it into a real type, and then multiply it by the magnetic scale resolution; S2: Conduct an effective value detection based on the read magnetic scale data. When the magnetic scale data is within 10 - 2000 mm, read the current magnetic scale data; otherwise, lock the previous data. Determine whether to enter the magnetic scale fault locking state. When the head of the strip passes the hot detector inside the coiler, continuously judge the effective value of the magnetic scale data. If the fault state lasts for more than 50 ms, enter the magnetic scale fault locking state; S3: After entering the magnetic scale fault locking state, perform corresponding control processing according to the position where the head of the strip is located. Specifically, it includes the following three processing methods: (1) When the head of the strip has not entered the coiling roll, the position is locked and remains unchanged; (2) After the head of the strip enters the coiling roll, the pressure ring of this coiling roll is pressed down until the pressing is completed; (3) After the pressing is completed, the open-loop negative current is turned on until the strip is ejected during coiling. After the strip is ejected during coiling, if the magnetic scale data returns to normal, cancel the magnetic scale fault locking state and return to the normal state.

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