Control method for reducing steel piling in rack after belt breakage

Abstract

The invention provides a control method for reducing steel heaping in a rack after belt breakage, which comprises the following steps of: detecting the speed of a motor through a main motor encoder of a No.5 rack, calculating the speed of an outlet of a rolling mill through a transmission system and the roller diameter of a current roller, and setting a standard speed according to a PLC (Programmable Logic Controller) system; the speed with the exit speed higher than the standard speed is defined as high speed; the strip breakage signals of the multiple rolling mills are connected in series, that is, when strip breakage happens to any rack, the strip breakage signals are triggered, and it is judged that strip breakage happens to any one or more rolling mills; if the speed is high and the belt is broken, a roll gap is automatically opened to reduce steel piling of a rolling mill stand; if the speed is high and the belt is not broken, the state is a normal steel rolling production state; and if the speed is not high but the belt is broken, the method is not executed. According to the control method, the control program of the PLC is optimized, automatic execution can be achieved, manual intervention is not needed, and the control method has the advantages of being high in efficiency and convenient to use and can be widely applied and popularized.

Description

Technical Field

[0001] The present invention relates to the technical field of PLC control systems, and in particular to a control method for reducing steel accumulation in a frame after a belt breaks. Background Art

[0002] The equipment in the area of ​​the pickling mill of the plate mill (using the Hitachi UCM5 frame 6-roller mill) is the key equipment of the pickling mill. The main equipment between the frames includes 1-5# main motor, 2-5# frame rear speed meter, 1-5# thickness gauge and frame rollers, etc. The maximum speed of the mill entrance is 350m / min, and the maximum speed of the mill exit is 1650m / min. When the mill breaks at high speed, it will have a great impact on the production of the entire unit. There are mainly the following problems: 1. High-speed belt breaking will cause major equipment and production accidents such as steel accumulation in the frame, main motor safety coupling pin breakage, guide plate damage, and roller damage. The cost of equipment and production spare parts such as damaged coupling pins and guide plates and rollers is high, resulting in an increase in the production cost of the unit; 2. It is difficult to handle the steel accumulation in the frame, and more personnel are required to handle it, which further increases the handling cost; 3. The handling takes up to 6-8 hours, which has a great impact on the rapid resumption of production of the unit.

[0003] By searching in the patent examination information databases of China and many countries, a control device and method for reducing the degree of damage caused by steel pile in a continuous rolling mill group was found, with application (patent) number: CN202010604277.0. The above patent was retrieved: according to the load state of the faulty rolling mill and the position of the rolled billet, the rotation of the relevant rolling mill in the faulty area is automatically stopped in time to minimize the losses caused by steel pile. Summary of the invention

[0004] According to the technical problems mentioned in the above background technology, a control method for reducing steel accumulation in the frame after strip breakage is provided. The invention does not require manual intervention, has the characteristics of high efficiency and convenience, and can be widely promoted and applied to cold and hot continuous rolling mills.

[0005] The technical means adopted by the present invention are as follows:

[0006] A control method for reducing steel accumulation in a rack after a belt breakage comprises the following steps:

[0007] Step 1: Detect the motor speed through the encoder of the main motor of the 5# frame, and then calculate the mill exit speed through the transmission system and the current roll diameter, and set the standard speed according to the PLC system; the exit speed higher than the standard speed is defined as high speed;

[0008] Step 2: Connect the belt-breaking signals of multiple rolling mills in series, that is, when a belt breaks in any frame, the belt-breaking signal is triggered, and it is determined that any one or more rolling mills have belt breaks;

[0009] Step 3: Determine whether it is high speed and the belt breaks; if it is high speed and the belt breaks, execute step 4; if it is high speed but the belt does not break, it is a normal production steel rolling state; if it is not high speed but the belt breaks, do not execute this method;

[0010] Step 4: The roll gap opens automatically to reduce steel accumulation in the rolling mill stands.

[0011] Furthermore, the step 4 includes the following steps: Step 41: the rolling mill automatically switches from a rolling mode to a roll changing mode;

[0012] Step 42: prepare for the roll gap opening; set the MASTER signal switching program of the rolling mill HYROP system, and the MASTER signal is immediately switched from the ON state to the OFF state;

[0013] Step 43: After the HYROP system MASTER state is switched to the OFF state, the transmission side and the operating side of the master hydraulic cylinder of each frame are lowered simultaneously;

[0014] Step 44: Open the roller gaps of each frame;

[0015] Step 45: Set the roller gap opening stop value. When the roller gap reaches the opening stop value, the transmission side and the operating side of the main hydraulic cylinder will no longer descend.

[0016] Furthermore, in step 43, the time for the transmission side and the operating side of the master hydraulic cylinder to descend simultaneously is 1 second.

[0017] Furthermore, a thickness gauge and a speed meter are also arranged on the frame; when a high-speed strip break occurs in the rolling mill, the thickness gauge in the frame automatically retreats to the rear end position, and the speed meter measurement shutter automatically closes.

[0018] Furthermore, in step 3, overspeed determination is implemented through a program preset in the PLC.

[0019] Furthermore, in step 43, there are 5 racks in total.

[0020] Furthermore, in step 42, when the MASTER signal is ON, the force motor valve is put into operation, and the force motor valve controls the action of the main hydraulic cylinder of each frame, and the opening and closing speed of the frame roll gap during action is 1mm / s; when the MASTER signal is OFF, the force motor valve is not put into operation, and the hydraulic bypass system is used to actuate the main hydraulic cylinder.

[0021] Furthermore, during the said action, the opening and closing speed of the frame roller gap is 6 mm / s to 7 mm / s.

[0022] Compared with the prior art, the present invention has the following advantages:

[0023] The control method optimizes the PLC control program. After the control program is optimized, it is automatically executed without manual intervention. It has the characteristics of high efficiency and ease of use, and can be widely promoted and applied in cold and hot rolling mills. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0025] Figure 1 It is a schematic diagram of the overall process of the present invention.

[0026] Figure 2 This is a schematic diagram of the roller gap of each frame opening to 18 mm in 3.4 seconds when the belt breaks at high speed according to the present invention. DETAILED DESCRIPTION

[0027] In order to enable those skilled in the art to better understand the scheme of the present invention, the technical scheme in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the present invention.

[0028] It should be noted that the terms "first", "second", etc. in the specification and claims of the present invention and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the data used in this way can be interchanged where appropriate, so that the embodiments of the present invention described herein can be implemented in an order other than those illustrated or described herein. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions, for example, a process, method, system, product or device that includes a series of steps or units is not necessarily limited to those steps or units that are clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0029] like Figure 1 As shown, the present invention provides a control method for reducing steel accumulation in a frame after a belt break, comprising the following steps:

[0030] Step 1: Detect the motor speed through the encoder of the main motor of the 5# frame, calculate the mill exit speed through the transmission system and the current roll diameter, and set the standard speed according to the PLC system; define the exit speed higher than the standard speed as high speed;

[0031] Step 2: Connect the belt-breaking signals of multiple rolling mills in series, that is, when a belt breaks in any frame, the belt-breaking signal is triggered, and it is determined that any one or more rolling mills have belt breaks;

[0032] Step 3: Implement overspeed judgment through the program preset in the PLC. Judge whether it is high speed and belt breakage occurs; if it is high speed and belt breakage occurs, execute step 4; if it is high speed but belt breakage does not occur, it is a normal production steel rolling state; if it is not high speed but belt breakage occurs, do not execute this method;

[0033] Step 4: The roll gap is automatically opened to reduce steel accumulation in the rolling mill frame. Step 4 includes the following steps:

[0034] Step 41: the rolling mill automatically switches from a rolling mode to a roll changing mode;

[0035] Step 42: prepare for the roll gap opening; set the MASTER signal switching program of the rolling mill HYROP system, and the MASTER signal is immediately switched from the ON state to the OFF state; in the step 42, when the MASTER signal is ON, the force motor valve is put into use, and the force motor valve controls the main hydraulic cylinder of each frame to move, and the frame roll gap opening and closing speed during the action is 1mm / s; when the MASTER signal is OFF, the force motor valve is not put into use, and the hydraulic bypass system moves the main hydraulic cylinder. During the action, the frame roll gap opening and closing speed is 6mm / s to 7mm / s.

[0036] Step 43: After the HYROP system MASTER state is switched to the OFF state, the transmission side and the operating side of the master hydraulic cylinder of each rack are lowered simultaneously; the driving side and the operating side of the master hydraulic cylinder are lowered simultaneously for 1 second. In this application, there are 5 racks in total.

[0037] Step 44: Open the roll gap of each frame; a thickness gauge and a speed meter are also arranged on the frame; when a high-speed strip break occurs in the rolling mill, the thickness gauge in the frame automatically retreats to the rear end position, and the speed meter measurement shutter automatically closes.

[0038] Step 45: Set the roller gap opening stop value. When the roller gap reaches the opening stop value, the transmission side and the operating side of the main hydraulic cylinder will no longer descend.

[0039] As a preferred embodiment, in the present application, because there are important single measuring devices such as thickness gauge and speed meter in the frame, and because after a high-speed strip break occurs in the frame, the tail swinging action at the strip break is large, which can easily cause damage to the equipment, the design program is executed so that when a high-speed strip break occurs in the rolling mill, the thickness gauge in the frame automatically retreats to the rear end position, and the speed meter measurement shutter automatically closes, to ensure the safe and stable operation of the measuring equipment. The serial numbers of the above-mentioned embodiments of the present invention are only for description and do not represent the advantages and disadvantages of the embodiments. In the above-mentioned embodiments of the present invention, the descriptions of each embodiment have their own emphases. For the parts not described in detail in a certain embodiment, please refer to the relevant descriptions of other embodiments. In the several embodiments provided in the present application, it should be understood that the disclosed technical content can be implemented in other ways.

[0040] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A control method for reducing steel accumulation in a frame after a belt break, characterized in that: The following steps are involved: Step 1: Detect the motor speed through the encoder of the main motor of the 5# frame, calculate the mill exit speed through the transmission system and the current roll diameter, and set the standard speed according to the PLC system; define the exit speed higher than the standard speed as high speed; Step 2: Connect the belt-breaking signals of multiple rolling mills in series, that is, when a belt breaks in any frame, the belt-breaking signal is triggered, and it is determined that any one or more rolling mills have belt breaks; Step 3: Determine whether it is high speed and the belt breaks; if it is high speed and the belt breaks, execute step 4; if it is high speed but the belt does not break, it is a normal production steel rolling state; if it is not high speed but the belt breaks, do not execute this method; Step 4: The roll gap opens automatically to reduce steel accumulation in the rolling mill stands.

2. A control method for reducing steel accumulation in a frame after a belt break according to claim 1, characterized in that: The step 4 includes the following steps: step 41: the rolling mill automatically switches from a rolling mode to a roll changing mode; Step 42: prepare for the roll gap opening; set the MASTER signal switching program of the rolling mill HYROP system, and the MASTER signal is immediately switched from the ON state to the OFF state; Step 43: After the HYROP system MASTER state is switched to the OFF state, the transmission side and the operating side of the master hydraulic cylinder of each frame are lowered simultaneously; Step 44: Open the roller gaps of each frame; Step 45: Set the roller gap opening stop value. When the roller gap reaches the opening stop value, the transmission side and the operating side of the main hydraulic cylinder will no longer descend.

3. A control method for reducing steel accumulation in a frame after a belt break according to claim 2, characterized in that: In step 43, the time for the driving side and the operating side of the master hydraulic cylinder to descend simultaneously is 1 second.

4. The control method for reducing steel accumulation in a frame after a belt breakage according to claim 1 is characterized in that: The frame is also provided with a thickness gauge and a speed meter; when a high-speed strip break occurs in the rolling mill, the thickness gauge in the frame automatically retreats to the rear end position, and the speed meter measuring shutter automatically closes.

5. The control method for reducing steel accumulation in a frame after a belt breakage according to claim 1 is characterized in that: In step 3, overspeed determination is implemented through a program preset in the PLC.

6. The control method for reducing steel accumulation in a frame after a belt breakage according to claim 1 is characterized in that: In step 43, there are 5 racks in total.

7. The control method for reducing steel accumulation in a frame after a belt breakage according to claim 1 is characterized in that: In step 42, when the MASTER signal is ON, the force motor valve is put into operation, and the force motor valve controls the main hydraulic cylinder of each frame to actuate. When the frame roll gap is actuated, the opening and closing speed is 1 mm / s; when the MASTER signal is OFF, the force motor valve is not put into operation, and the hydraulic bypass system is used to actuate the main hydraulic cylinder.

8. The control method for reducing steel accumulation in the frame after belt breakage according to claim 7 is characterized in that: During the above action, the opening and closing speed of the frame roller gap is 6 mm / s to 7 mm / s.

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