Method and system for improving opening precision of descaling valve of rolling system

Abstract

The application discloses a method and system for improving the opening precision of a descaling valve of a steel rolling system, and the method comprises the following steps: recording the time required from issuing a descaling valve action instruction to the end of the descaling valve action each time; when the time exceeds a threshold value, obtaining a compensation distance for triggering the descaling valve according to the current time and the speed of a roller table transporting a slab during descaling; and correcting the position of triggering the descaling valve to open according to the compensation distance to obtain the actual opening position of the descaling valve. The application tracks the state of the descaling valve by recording the time required from issuing a descaling valve action instruction to the end of the descaling valve action each time, and when the state change exceeds a preset threshold value, the deviation value can be automatically tracked and the opening time of the descaling valve is corrected, so that the descaling effect remains unchanged when the state of the equipment changes.

Description

Technical Field

[0001] This invention relates to a method and system for improving the opening accuracy of descaling valves in steel rolling systems. Background Technology

[0002] The production process of medium and heavy plates generally consists of several main steps, including heating, rolling, and shearing. During the heating process in the furnace, a large amount of iron oxide scale is generated on the slab to be rolled. This scale needs to be removed before rolling to prevent it from being pressed into the surface or even the interior of the steel plate, forming defects and resulting in scrap. In the steel rolling production line, removing the iron oxide scale before rolling is a crucial step, generally called descaling. The effectiveness of descaling determines whether the iron oxide scale can be completely removed from the steel plate.

[0003] Several key factors related to descaling effectiveness include: 1. Descaling water pressure; 2. The angle and height of the descaling nozzle; 3. The condition of the descaling nozzle; and 4. The time and timing of descaling. The time and timing of descaling primarily refer to the duration of the steel plate being impacted by the descaling water. Since the steel plate continues to move during descaling, this is also related to the speed of the steel plate during descaling and the timing of the opening and closing of the descaling valve.

[0004] The descaling speed is generally determined by production personnel based on factors such as production rhythm and steel type, drawing on production experience. Currently, there are two common control methods for the opening and closing time of the descaling valve: one is that the operator manually triggers the valve's opening time, and the valve automatically closes after the steel plate tracks away from a certain position or reaches a pre-set fixed opening time; the other is based on the steel plate's tracking signal, automatically triggering the valve to open when the head of the steel plate reaches a certain position, and automatically closing when the tail of the steel plate exceeds a certain position or the maximum allowable descaling time is reached. Therefore, it is clear that, from multiple perspectives such as the degree of automation and water consumption, method two is superior to method one.

[0005] However, in actual production operations, another factor needs to be considered: the opening time of the descaling valve (i.e., the time from receiving the opening command to the valve being fully open) is not constant. A new valve may open in 2-3 seconds, while a valve that has been used for a long time or is in poor condition may take 5-6 seconds or even longer to open normally. During descaling, the speed of the steel plate is generally 0.8-1.2 m / s. A difference of 3 seconds is equivalent to a deviation of more than 3 meters between the expected position of the steel plate and its actual position when the descaling valve actually opens. This situation either results in incomplete descaling of some parts of the steel plate or a significant waste of descaling water and electricity. Summary of the Invention

[0006] To overcome the shortcomings of the prior art, the present invention provides a method and system for improving the opening accuracy of the descaling valve in a steel rolling system, thereby solving the problem of poor descaling effect caused by changes in equipment status.

[0007] According to one aspect of the present invention, a method for improving the opening accuracy of a descaling valve in a steel rolling system is provided, comprising:

[0008] Record the time required from issuing the descaling valve action command to the end of the descaling valve action each time.

[0009] When the time exceeds the threshold, the compensation distance for triggering the descaling valve is obtained based on the current time and the speed of the slab conveyed by the roller conveyor during descaling.

[0010] Based on the compensation distance, the position that triggers the opening of the descaling valve is corrected to obtain the actual opening position of the descaling valve.

[0011] The above technical solution tracks the state of the descaling valve by recording the time required from issuing the descaling valve action command to the end of the descaling valve action each time. When the state change exceeds a preset threshold, it can automatically track the deviation value and correct the opening time of the descaling valve, so as to achieve the purpose of keeping the descaling effect unchanged when the equipment state changes.

[0012] Furthermore, the above technical solution improves the accuracy of descaling control by monitoring the equipment status of the descaling valve in real time and automatically correcting the opening time of the descaling valve, thereby ensuring the descaling effect of the steel plate and achieving the goal of saving water and electricity.

[0013] As a further technical solution, the method further includes: installing a first proximity switch and a second proximity switch at the actual open position and closed position of the descaling valve, respectively, wherein the first proximity switch is used to send a command to the control terminal when the descaling valve is in position, so as to determine the time point when the descaling valve is fully open; the second proximity switch is used to send a command to the control terminal when the descaling valve is in position, so as to determine the time point when the descaling valve is fully closed.

[0014] As a further technical solution, the method further includes: when issuing the descaling valve opening command, recording the time point of issuing the opening command as T1; obtaining the command sent by the first proximity switch, determining the time point when the descaling valve is fully opened and recording it as T2; and obtaining the time from issuing the opening command to the full opening of the descaling valve as T2-T1 based on T1 and T2.

[0015] As a further technical solution, the method further includes: when the time T2-T1 exceeds the threshold, obtaining the compensation distance for triggering the opening of the descaling valve based on the speed V of the roller conveyor transporting the slab during descaling and the time T2-T1; and correcting the position for triggering the opening of the descaling valve based on the compensation distance to obtain the actual opening position of the descaling valve.

[0016] As a further technical solution, the method further includes: when issuing a descaling valve closing command, recording the time point of issuing the closing command as T3; obtaining the command sent by the second proximity switch, determining the time point when the descaling valve is fully closed and recording it as T4; and obtaining the time from issuing the closing command to the full closure of the descaling valve as T4-T3 based on T3 and T4.

[0017] As a further technical solution, the method further includes: when the time T4-T3 exceeds the threshold, obtaining the compensation distance for triggering the closing of the descaling valve based on the speed V of the roller conveyor transporting the slab during descaling and the time T4-T3; and correcting the position for triggering the opening of the descaling valve based on the compensation distance to obtain the actual opening position of the descaling valve.

[0018] As a further technical solution, the method also includes: tracking the head position of the steel plate, and triggering the descaling valve to open when the head position reaches a preset position or a corrected actual position.

[0019] According to one aspect of the present invention, a system for improving the opening accuracy of a descaling valve in a steel rolling system is provided, the system comprising:

[0020] The time recording module is used to record the time required from the issuance of the descaling valve action command to the completion of the descaling valve action each time;

[0021] The distance compensation module is used to obtain the compensation distance for triggering the descaling valve based on the current time and the speed of the slab conveyed by the roller conveyor during descaling when the time exceeds the threshold.

[0022] The actual position determination module is used to correct the position that triggers the opening of the descaling valve based on the compensation distance, so as to obtain the actual opening position of the descaling valve.

[0023] As a further technical solution, the system also includes a first proximity switch and a second proximity switch installed at the actual open and closed positions of the descaling valve, respectively. The first proximity switch is used to send a command to the control terminal when it detects that the descaling valve is in position, so as to determine the time point when the descaling valve is fully open. The second proximity switch is used to send a command to the control terminal when it detects that the descaling valve is in position, so as to determine the time point when the descaling valve is fully closed.

[0024] As a further technical solution, the system also includes a tracking module for tracking the head position of the steel plate, and triggering the descaling valve to open when the head position reaches a preset position or a corrected actual position.

[0025] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0026] 1) This invention detects and counts the opening time of the descaling valve by proximity switch, automatically tracks the equipment status of the descaling valve, provides equipment maintenance personnel with a measurable basis for the equipment status, and at the same time, when the equipment status deteriorates but cannot be dealt with immediately, the control system automatically compensates for the opening time of the descaling valve, thereby compensating for the deficiencies in the equipment status through control, and thus ensuring the purpose of descaling effect.

[0027] 2) This invention, through precise control of detection instruments and control systems, avoids the problem of intentionally opening the descaling system prematurely to prevent poor descaling results, thus avoiding waste of descaling water and electricity, and provides effective support for enterprises to save costs.

[0028] 3) The entire process of this invention is fully automated, requiring no additional effort or tools from equipment maintenance personnel, providing a convenient and reliable monitoring method for the reliable operation of the equipment throughout its entire life cycle. Attached Figure Description

[0029] Figure 1 This is a schematic diagram of the arrangement of the descaling box according to an embodiment of the present invention.

[0030] Figure 2 This is a schematic diagram showing the open and closed positions of the descaling valve according to an embodiment of the present invention.

[0031] Figure 3 This is a schematic diagram of the descaling logic of the descaling box according to an embodiment of the present invention.

[0032] Figure 4 This is a schematic diagram showing the time delay from receiving a command to fully opening the descaling valve according to an embodiment of the present invention. Detailed Implementation

[0033] The technical solutions of various embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0034] This invention provides a method for improving the opening accuracy of descaling valves in steel rolling systems. It automatically corrects the opening time of the descaling valve, improving its accuracy and achieving efficient and precise descaling control. The objectives of this invention are: 1. To automatically track deviation values ​​and correct the opening time of the descaling valve through a monitoring program when the descaling valve equipment status changes, thereby improving the accuracy of descaling control; 2. To ensure the descaling effect on steel plates and save water and electricity through precise control of the descaling valve.

[0035] The arrangement of the descaling box in this invention is as follows: Figure 1As shown, the steel plate heated in the heating furnace moves in the direction of the rolling mill and passes through descaling nozzle 1 and descaling nozzle 2 in sequence to complete the descaling of the steel plate.

[0036] The technical solution adopted in this invention is:

[0037] 1) Install proximity switches with detection elements in the actual open and closed positions of the descaling valve to detect the time points when the descaling valve is fully open and fully closed.

[0038] 2) By writing a control program through the automation system, the time required for the descaling valve to complete its action from the issuance of the opening command can be recorded, and this time can be displayed on the operation screen (e.g., ...). Figure 4 (as shown);

[0039] 3) A new descaling valve opening compensation program has been added. The compensation logic is that, instead of triggering the valve opening command when the steel plate head reaches B, it is now modified so that the descaling valve opening command is triggered when the steel plate position reaches B-(T2-T1)*V. This enables automatic correction and compensation of the descaling valve triggering, achieving precise control of the descaling valve and realizing accurate descaling.

[0040] like Figure 3 As shown, the slab to be rolled is heated in a furnace and then transported to the rolling mill via a roller conveyor. Before rolling, it generally needs to pass through a descaling box for descaling. The entire descaling process is carried out while the slab is being transported forward, with the descaling valve being opened and controlled simultaneously. Ideally, the valve is fully opened when the head of the slab reaches the preset descaling valve opening position A, resulting in the best descaling and energy-saving effects. Opening the descaling valve too early wastes descaling water and electricity, while opening it too late can easily lead to incomplete descaling in some areas of the slab, causing iron oxide scale to be pressed into the interior of the steel plate during rolling.

[0041] When the descaling valve is in good condition, the steel plate head is transported to Figure 3 The descaling valve opening command is triggered at position B (i.e., the coordinate position where the head position H in the tracking program is greater than or equal to B), ensuring the valve is fully open when the slab reaches position A. However, with continuous use and changes in the descaling valve's status, the time from receiving the command to full opening will vary. Significant variations can cause inaccurate valve opening timing, affecting the descaling effect. Therefore, the descaling valve opening time needs to be corrected.

[0042] like Figure 2 As shown, by adding a control program to the control system, the control logic is to record the period from when the control system issues the command to open the descaling valve until the descaling valve is fully opened (i.e., ...). Figure 2The time T is the time when the proximity switch 1 receives the signal. The time from the triggering of the descaling valve at position B to the complete opening of position A in the initial state is set as T1. When the state of the descaling valve changes, the time from the triggering of the opening command to the complete opening of the descaling valve becomes T2. When the ratio of T2 to T1 exceeds a certain time (such as 2 seconds), the opening time of the descaling valve needs to be corrected.

[0043] The correction logic is: BC = (T2 - T1) * V (V is the speed of the slab transported by the roller conveyor during descaling). After correction, when the head of the slab reaches position B, the descaling valve is triggered by the control system to open, thus achieving the goal of precise control of the descaling valve.

[0044] Before the technical solution described in this invention was applied to actual sites, if the theoretical calculations were strictly followed, i.e., the descaling valve was always automatically triggered to open at position B, changes in the descaling valve's state could easily lead to incomplete descaling of the steel plate head. To ensure descaling effectiveness, the valve was manually opened for a certain period of time in advance. However, this method easily resulted in wasted descaling water, leading to ineffective energy consumption. This invention, through real-time monitoring and correction, can consistently guarantee descaling effectiveness while avoiding the ineffective waste of descaling water and energy. Statistics show that this invention, when applied to the site, can save companies 1500 kWh / day in electricity costs.

[0045] The present invention also provides a system for improving the opening accuracy of descaling valves in a steel rolling system, the system comprising:

[0046] The time recording module is used to record the time required from the issuance of the descaling valve action command to the completion of the descaling valve action each time;

[0047] The distance compensation module is used to obtain the compensation distance for triggering the descaling valve based on the current time and the speed of the slab conveyed by the roller conveyor during descaling when the time exceeds the threshold.

[0048] The actual position determination module is used to correct the position that triggers the opening of the descaling valve based on the compensation distance, so as to obtain the actual opening position of the descaling valve.

[0049] The system also includes a first proximity switch and a second proximity switch installed at the actual open and closed positions of the descaling valve, respectively. The first proximity switch is used to send a command to the control terminal when it detects that the descaling valve is in position, so as to determine the time point when the descaling valve is fully open. The second proximity switch is used to send a command to the control terminal when it detects that the descaling valve is in position, so as to determine the time point when the descaling valve is fully closed.

[0050] The system also includes a tracking module for tracking the head position of the steel plate, and triggering the descaling valve to open when the head position reaches a preset position or a corrected actual position.

[0051] The system works as follows: proximity switches installed at the actual open and closed positions of the descaling valve detect the time points when the descaling valve is fully open and fully closed; an automated control program is written to record the time required for each descaling valve action from the issuance of the opening command; an opening deviation compensation logic is added to the original opening control logic, using the previously calculated descaling valve opening time combined with the current descaling roller speed to incorporate the descaling valve opening time into the control compensation function, thereby achieving precise control of the descaling valve opening.

[0052] The implementation of the system can be carried out with reference to the method implementation.

[0053] 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 foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the technical solutions of the embodiments of the present invention.

Claims

1. A method for improving the opening accuracy of a descaling valve in a steel rolling system, characterized in that, include: Record the time required from issuing the descaling valve action command to the end of the descaling valve action each time; When the time exceeds the threshold, the compensation distance for triggering the descaling valve is obtained based on the current time and the speed of the slab conveyed by the roller conveyor during descaling. Based on the compensation distance, the position triggering the opening of the descaling valve is corrected to obtain the actual opening position of the descaling valve; wherein, the method further includes: installing a first proximity switch and a second proximity switch at the actual open position and the closed position of the descaling valve, respectively; when the descaling valve opening command is issued, the time point of issuing the opening command is recorded as T1; the command sent by the first proximity switch is obtained, the time point when the descaling valve is fully opened is determined and recorded as T2; the time from issuing the opening command to the descaling valve being fully opened is obtained based on T1 and T2, which is used as the time required from issuing the descaling valve action command to the end of the descaling valve action; and, when the descaling valve closing command is issued, the time point of issuing the closing command is recorded as T3; the command sent by the second proximity switch is obtained, the time point when the descaling valve is fully closed is determined and recorded as T4; the time from issuing the closing command to the descaling valve being fully closed is obtained based on T3 and T4.

2. The method for improving the opening accuracy of the descaling valve in a steel rolling system according to claim 1, characterized in that, The first proximity switch is used to send a command to the control terminal when it detects that the descaling valve is in position, so as to determine the time point when the descaling valve is fully open; the second proximity switch is used to send a command to the control terminal when it detects that the descaling valve is in position, so as to determine the time point when the descaling valve is fully closed.

3. The method for improving the opening accuracy of the descaling valve in a steel rolling system according to claim 1, characterized in that, The method further includes: when the time T2-T1 exceeds a threshold, obtaining a compensation distance to trigger the opening of the descaling valve based on the speed V of the roller conveyor transporting the slab during descaling and the time T2-T1; and correcting the position of triggering the opening of the descaling valve based on the compensation distance to obtain the actual opening position of the descaling valve.

4. The method for improving the opening accuracy of the descaling valve in a steel rolling system according to claim 1, characterized in that, The method further includes: when the time T4-T3 exceeds the threshold, obtaining the compensation distance for triggering the closing of the descaling valve based on the speed V of the roller conveyor transporting the slab during descaling and the time T4-T3; and correcting the position for triggering the opening of the descaling valve based on the compensation distance to obtain the actual opening position of the descaling valve.

5. The method for improving the opening accuracy of the descaling valve in a steel rolling system according to claim 1, characterized in that, The method further includes: tracking the head position of the steel plate, and triggering the descaling valve to open when the head position reaches a preset position or a corrected actual position.

6. A system for improving the opening accuracy of descaling valves in a steel rolling system, characterized in that, The system includes: The time recording module is used to record the time required from the issuance of the descaling valve action command to the completion of the descaling valve action each time; The distance compensation module is used to obtain the compensation distance for triggering the descaling valve based on the current time and the speed of the slab conveyed by the roller conveyor during descaling when the time exceeds the threshold. The actual position determination module is used to correct the position of triggering the opening of the descaling valve based on the compensation distance to obtain the actual opening position of the descaling valve. The system further includes: installing a first proximity switch and a second proximity switch at the actual open and closed positions of the descaling valve, respectively; recording the time point of issuing the opening command as T1 when the descaling valve opening command is issued; acquiring the command sent by the first proximity switch, determining the time point at which the descaling valve is fully opened and recording it as T2; obtaining the time from issuing the opening command to the descaling valve being fully opened based on T1 and T2, as the time required from issuing the descaling valve action command to the end of the descaling valve action; and recording the time point of issuing the closing command as T3 when the descaling valve closing command is issued; acquiring the command sent by the second proximity switch, determining the time point at which the descaling valve is fully closed and recording it as T4; obtaining the time from issuing the closing command to the descaling valve being fully closed based on T3 and T4.

7. The system for improving the opening accuracy of the descaling valve in a steel rolling system according to claim 6, characterized in that, The first proximity switch is used to send a command to the control terminal when it detects that the descaling valve is in position, so as to determine the time point when the descaling valve is fully open; the second proximity switch is used to send a command to the control terminal when it detects that the descaling valve is in position, so as to determine the time point when the descaling valve is fully closed.

8. The system for improving the opening accuracy of the descaling valve in a steel rolling system according to claim 6, characterized in that, The system also includes a tracking module for tracking the head position of the steel plate, and triggering the descaling valve to open when the head position reaches a preset position or a corrected actual position.

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