A production rhythm control method and system

Abstract

This invention provides a production rhythm control method and system, relating to the field of hot strip mill production rhythm control technology. The method includes: dividing the rolling line into zones according to the layout of process equipment, determining anti-collision points, designating safe operation checkpoints, setting safe intervals between front and rear strips, and simultaneously setting the shoveling interval and minimum shoveling time; calculating the time it takes for the head and tail of the strip to reach the anti-collision points; calculating the time difference between the head of the rear strip and the tail of the front strip reaching the anti-collision points; calculating the shoveling waiting time for the rear strip based on the time difference and the safe distance; and controlling the production rhythm based on the waiting time. This invention can reduce the occurrence of rear-end collisions between the front and rear strips; improve the accuracy of the steel extraction time in the heating furnace, increase production efficiency, and reduce labor intensity; and can be applied to various process-oriented production lines or units. The technology is simple to implement and easy to promote.

Description

Technical Field

[0001] The present invention relates to the technical field of hot rolling production rhythm control, and in particular to a production rhythm control method and system. Background Art

[0002] Hot rolling generally refers to a strip steel rolling production line that includes heating furnace, rough rolling, finishing rolling, layer cooling and coiling processes. It is a typical high-speed real-time manufacturing process and system. Generally, there are multiple strip steels rolling on the production line at the same time. In order to continuously improve production capacity, the production line usually rolls at the fastest steel extraction rhythm and the fastest speed to pursue the greatest benefits. Affected by various conditions or unforeseen factors such as the rationality of planning, equipment status and control system stability, real-time high speed and fast rhythm will lead to many abnormalities and even accidents, and the rolling rhythm needs to be controlled.

[0003] The common rolling rhythm control method is mainly to control the steel extraction rhythm of the heating furnace, including manual steel extraction, fixed cycle steel extraction and automatic steel extraction. Manual steel extraction is determined by the heating furnace operator or dispatcher through observing the production situation of the hot rolling line and judging the steel extraction time of each slab based on the site and experience. Fixed cycle steel extraction is performed by the control system according to the set steel extraction interval time. Automatic steel extraction is automatically predicted by the computer system by predicting the rolling bottleneck time.

[0004] The Chinese invention patent with publication number CN112334242A discloses a rolling rhythm control system, in which a rolling rhythm calculator performs rolling rhythm control based on the rolling specification SP_SS of the steel plate (SS) and the information of the rolling condition C_SS. In the rolling rhythm control, an optimization process focusing on three steel plates (SS) that are continuously rolled is performed. In the optimization process, the optimal condition OC_SS of the second steel plate (SS) that can shorten the withdrawal interval I_TEX is derived. The withdrawal interval I_TEX is the sum of the withdrawal interval I_EX between the first and second and the withdrawal interval I_EX between the second and third. In the rolling rhythm control, the withdrawal time of the second steel plate (SS) is calculated based on the withdrawal interval I_EX in the optimal condition OC_SS and the withdrawal time of the first steel plate (SS).

[0005] The Chinese invention patent with the publication number CN109663815A discloses a control method and system for automatic steel extraction during hot rolling, including: step 1, the heating furnace steel extraction management system obtains the physical parameters related to the slab rolling process, establishes a rolling rhythm mathematical model to calculate the slab running time, and then accumulates the running time to predict the time of the initial slab at any time point; step 2, the bottleneck time is calculated by the time at any time point obtained in step 1, the bottleneck time of each position point is added to the safety margin time and the maximum value of the maximum safety interval time is selected, which is the minimum steel extraction interval time; step 3, the system notifies the management program of the heating furnace steel extraction management system by connecting the minimum steel extraction interval time. The method described in the invention can realize the accurate prediction of the slab running time and bottleneck time without human intervention, and automatically complete the steel extraction function, effectively improving the hot rolling production capacity and reducing the labor load of operators.

[0006] The above inventions are mainly designed to improve the accuracy of steel extraction time of the heating furnace, with the goal of improving output efficiency and reducing labor intensity. However, these methods do not have the function of adjusting and controlling the running status of the strip during the actual rolling process, and cannot avoid the collision problem between the front and rear strips that may be caused by prediction deviation. Summary of the invention

[0007] In view of the defects in the prior art, the present invention provides a production rhythm control method and system.

[0008] According to a production rhythm control method and system provided by the present invention, the scheme is as follows:

[0009] In a first aspect, a production rhythm control method is provided, the method comprising:

[0010] Step S1: Divide the rolling line into areas according to the layout of the process equipment, determine the anti-collision points, specify the safe operation check points, the safe spacing distance between the front and rear strips, and set the swing interval and the minimum swing time;

[0011] Step S2: Calculate the time for the head and tail of the strip to reach the anti-collision point respectively;

[0012] Step S3: Calculate the time difference between the head of the rear strip and the tail of the front strip reaching the anti-collision point;

[0013] Step S4: Calculate the waiting time for the rear steel strip to swing according to the time difference between the head of the rear steel strip and the tail of the front steel strip reaching the anti-collision point and the safety distance;

[0014] Step S5: Control the production rhythm according to the waiting time.

[0015] Preferably, the step S1 comprises:

[0016] Step S1.1: according to the rolling line equipment layout, the flying shear at the finishing rolling entrance is determined as a safety checkpoint, the pinch roller at the coiling entrance is used as an anti-collision point, and the middle roller area in front of the flying shear is set as a steel swing area;

[0017] Step S1.2: Taking the safety checkpoint as the reference position and as the starting point for calculating the time for the strip to run to the anti-collision point, the distance between the finishing entrance flying shear, the anti-collision point and the safety checkpoint is determined according to the equipment layout;

[0018] Step S1.3: Set the safety distance between the front and rear strips. In case of collision, consider the calculation error and set a minimum swing time T s .

[0019] Preferably, step S2 comprises:

[0020] Step S2.1: When the front strip S1 reaches the flying shear position at the finishing entrance, calculate the first time T of the head of the front strip S1 reaching the anti-collision point according to Newton's equation of motion. head , while saving the first time T head ;

[0021] Step S2.2: When the front strip S1 reaches the flying shear position at the finishing entrance, calculate the first time T of the tail of the front strip S1 reaching the anti-collision point according to Newton's motion equation. tail , while saving the first time T tail ;

[0022] Step S2.3: When the rear strip S2 reaches the flying shear position at the finishing entrance, the second time T when the head of the rear strip S2 reaches the anti-collision point is calculated in the same manner as steps S2.1 and S2.2. head The second time T when the tail of the rear strip S2 reaches the anti-collision point tail .

[0023] Preferably, the step S3 comprises: calculating the first time T of the front strip S1 tail and the second time T of the rear strip S2 head The difference △t.

[0024] Preferably, step S4 comprises:

[0025] Step S4.1: Determine the size of △t. If △t is not greater than 0, there will be no collision. Set the swing time T of the rear strip S2. osc 0, if it is greater than 0 and less than the safety time T s , T osc Set to T s , otherwise set the swing time T osc is △t;

[0026] Step S4.2: Set the swing time T of the rear strip S2 osc It is sent to the basic automation control system to execute swing steel waiting control on the rear strip S2.

[0027] In a second aspect, a production rhythm control system is provided, the system comprising:

[0028] Module M1: Divide the rolling line into areas according to the layout of process equipment, determine anti-collision points, specify safe operation checkpoints, safe spacing between front and rear strips, and set the swing interval and minimum swing time;

[0029] Module M2: Calculate the time for the head and tail of the strip to reach the anti-collision point respectively;

[0030] Module M3: Calculate the time difference between the head of the rear strip and the tail of the front strip reaching the anti-collision point;

[0031] Module M4: Calculate the waiting time for the rear piece of steel to swing according to the time difference between the head of the rear piece of steel and the tail of the front piece of steel reaching the anti-collision point and the safety distance;

[0032] Module M5: Control the production rhythm according to the waiting time.

[0033] Preferably, the module M1 comprises:

[0034] Module M1.1: According to the layout of the rolling line equipment, the flying shear at the finishing rolling entrance is determined as the safety inspection point, the pinch roller at the coiling entrance is used as the anti-collision point, and the middle roller area in front of the flying shear is set as the swing steel area;

[0035] Module M1.2: Take the safety checkpoint as the reference position and as the starting point for calculating the time for the strip to run to the anti-collision point. At the same time, determine the distance between the finishing entrance flying shear, the anti-collision point and the safety checkpoint according to the equipment layout;

[0036] Module M1.3: Set the safety distance between the front and rear strips. In case of collision, consider the calculation error and set a minimum swing time T s .

[0037] Preferably, the module M2 comprises:

[0038] Module M2.1: When the front strip S1 reaches the flying shear position at the finishing entrance, calculate the first time T when the head of the front strip S1 reaches the anti-collision point according to Newton's equation of motion. head , while saving the first time T head ;

[0039] Module M2.2: When the front strip S1 reaches the flying shear position at the finishing entrance, calculate the first time T when the tail of the front strip S1 reaches the anti-collision point according to Newton's motion equation tail, while saving the first time T tail ;

[0040] Module M2.3: When the rear strip S2 reaches the flying shear position at the finishing entrance, the second time T of the head of the rear strip S2 reaching the anti-collision point is calculated according to modules M2.1 and M2.2. head The second time T when the tail of the rear strip S2 reaches the anti-collision point tail .

[0041] Preferably, the module M3 comprises: calculating the first time T of the preceding strip S1 tail and the second time T of the rear strip S2 head The difference △t.

[0042] Preferably, the module M4 includes:

[0043] Module M4.1: Determine the size of △t. If △t is not greater than 0, there will be no collision. Set the swing time T of the rear strip S2. osc 0, if it is greater than 0 and less than the safety time T s , T osc Set to T s , otherwise set the swing time T osc is △t;

[0044] Module M4.2: Set the swing time T of the rear strip S2 osc It is sent to the basic automation control system to execute swing steel waiting control on the rear strip S2.

[0045] Compared with the prior art, the present invention has the following beneficial effects:

[0046] 1. By setting a safe distance and adjusting the rhythm or speed control of the rear strip, the rear strip is made to wait in the swing area, thus avoiding rear-end collision accidents between the front and rear strips;

[0047] 2. The present invention improves the steel extraction time accuracy of the heating furnace, improves the output efficiency and reduces the labor intensity;

[0048] 3. The present invention can be applied to various process production lines or units, and the technology is simple and easy to implement and promote. BRIEF DESCRIPTION OF THE DRAWINGS

[0049] Other features, objects and advantages of the present invention will become more apparent from the detailed description of non-limiting embodiments made with reference to the following drawings:

[0050] Figure 1 It is the flow chart of collision avoidance control calculation;

[0051] Figure 2This is the layout diagram of the hot rolling production line;

[0052] Figure 3 Schematic diagram for setting up key positions for collision avoidance control. DETAILED DESCRIPTION

[0053] The present invention is described in detail below in conjunction with specific embodiments. The following embodiments will help those skilled in the art to further understand the present invention, but are not intended to limit the present invention in any form. It should be noted that, for those of ordinary skill in the art, several changes and improvements can also be made without departing from the concept of the present invention. These all belong to the protection scope of the present invention.

[0054] The embodiment of the present invention provides a production rhythm control method, referring to Figure 1 As shown, the method specifically comprises the following steps:

[0055] Step S1: Divide the rolling line into areas according to the layout of the process equipment, determine the anti-collision points, specify the safe operation checkpoints, the safe spacing distance between the front and rear strips, and set the swing interval and the minimum swing time T s ;

[0056] This step specifically includes:

[0057] According to the layout of the rolling line equipment, the flying shear at the finishing rolling entrance is determined as a safety inspection point, the pinch roller at the coiling entrance is used as an anti-collision point, and the middle roller area in front of the flying shear is set as a swing steel area;

[0058] The safety checkpoint is used as the reference position and as the starting point for calculating the time for the strip to run to the anti-collision point. At the same time, the distance between the finishing entrance flying shear, the anti-collision point and the safety checkpoint is determined according to the equipment layout;

[0059] Set the safety distance between the front and rear strips. In case of possible collision, consider the calculation error and set a minimum swing time T s .

[0060] Step S2: Calculate the time T for the head and tail of the strip to reach the point prone to rear-end collision, i.e., the anti-collision point. head and T tail .

[0061] In this step, the step specifically includes:

[0062] When the front strip S1 reaches the flying shear CS at the entrance of the finishing mill FM, i.e., the safety checkpoint, according to Newton's motion equation, the distance from the start of the flying shear to the entrance of the finishing mill F1, the spacing of the stands, the distance from the exit of the finishing mill stand F7 to the pinch roller before coiling, and the running speed of the strip head obtained by the calculation model of the finishing pass, the time when the head of the front strip S1 reaches the pinch roller before coiling, i.e., the anti-collision point, is calculated, and the first time T is saved at the same time. head ;

[0063] When the front strip S1 reaches the flying shear position at the finishing entrance, i.e., the safety checkpoint, according to Newton's equation of motion, the distance from the flying shear entrance to the finishing F1 entrance, the spacing of the stands, the distance from the finishing stand F7 exit to the pinch roller before coiling, and the running speed of the strip tail obtained by the finishing pass calculation model are known. The time when the front strip S1 tail reaches the anti-collision point of the pinch roller before coiling is calculated, and the first time T is saved at the same time. tail ;

[0064] When the rear strip S2 reaches the CS position of the finishing FM entrance flying shear, i.e., the safety checkpoint, the second time T when the head of the rear strip S2 reaches the anti-collision point is calculated in the same way as above. head The second time T when the tail of the rear strip S2 reaches the anti-collision point tail .

[0065] Step S3: Calculate the time difference △t between the head of the rear strip and the tail of the front strip reaching the anti-collision point. This step specifically calculates the first time T of the front strip S1. tail and the second time T of the rear strip S2 head The difference △t.

[0066] Step S4: Calculate the swing waiting time T of the rear piece of steel according to the time difference between the head of the rear piece of steel and the tail of the front piece of steel reaching the anti-collision point and the safety distance. osc In this step, the size of △t is determined. If △t is not greater than 0, no collision will occur. The swing time T of the rear strip S2 is set. osc 0, if it is greater than 0 and less than the safety time T s , T osc Set to T s , otherwise set the swing time T osc =△t; the swing time T of the rear strip S2 osc It is sent to the basic automation control system to execute swing steel waiting control on the rear strip S2.

[0067] Step S5: By executing the swing steel waiting control on the rear strip steel S2, the overall production rhythm is adjusted.

[0068] Next, the present invention will be described in more detail.

[0069] The present invention aims at the possible collision accident of the front and rear strips on the hot-rolled strip production line, and determines the possibility of collision by online calculating the running diagram of the front and rear strips and the time to reach the safety checkpoint. If there is a possibility of collision, a safety distance is set, and the rhythm or speed control of the rear strip is adjusted to make the rear strip wait in the swing steel area, thereby avoiding the rear-end collision accident of the front strip and the rear strip.

[0070] First, the rolling line is divided into areas according to the layout of the process equipment, the prone points of rear-end collision accidents are determined, the safe operation checkpoints and the safe interval between the front and rear strips are specified, and the swing interval and the minimum swing time T are set. s ; Then calculate the time T when the head and tail of the strip reach the rear-end collision prone point respectively head and T tail ; Further calculate the time difference △t between the head of the rear strip and the tail of the front strip reaching the prone point of rear-end collision accident; According to the time difference between the head of the rear strip and the tail of the front strip reaching the prone position of accident and the safety distance, calculate the swing waiting time T of the rear strip osc , and send the steel swing time to the basic automation control system to execute the steel swing waiting time of the rear strip.

[0071] Taking the production process of a hot rolling production line on a certain day as an example, the steps and processes included in this technical solution are explained with reference to Figure 1 shown.

[0072] The information of the front strip S1 in the example is: intermediate billet thickness 45.29mm, intermediate billet incoming temperature 1029℃, target thickness 3.80mm, target temperature 880℃.

[0073] The information of the rear strip S2 in the example is: the intermediate billet incoming material thickness is 44.40mm, the intermediate billet incoming material temperature is 1027℃, the target thickness is 3.66mm, and the target temperature is 890℃.

[0074] The example refers to the front strip S1 with a slightly thicker thickness and a slightly lower final rolling temperature, the rear strip S2 with a slightly thinner thickness and a slightly higher final rolling temperature. The speed curve calculated by the finishing rolling model is:

[0075]

[0076] First, refer to Figure 2 and Figure 3 As shown, the rolling line is divided into areas according to the layout of the process equipment, the anti-collision prone points are determined, the safe operation check points are designated, the safety interval between the front strip S1 and the rear strip S2 is set, and the swing steel interval is set;

[0077] Production line equipment layout and basic parameters:

[0078] The reference coordinate of the flying shear CS at the finishing entrance is 0;

[0079] The finishing rolling F1 stand is located at 14.4m.

[0080] The spacing between finishing mill stands is 5.5m.

[0081] 148m from finishing rolling F7 to the anti-collision point before coiling,

[0082] Safety distance 20m,

[0083] Minimum swing time 10 seconds;

[0084] The swing steel section is located in front of the flying shear at the finishing rolling entrance.

[0085] Secondly, calculate the time for the head and tail of the strip to reach the point prone to rear-end collision accidents;

[0086] According to the pass data of the front strip S1 and the rear strip S2 calculated according to the finishing pass model and the speed data of each section, the time for the head and tail of the rear strip S1 and S2 to arrive at the safety checkpoint before coiling can be conveniently calculated according to Newton's motion equation. The head of the front strip S1 arrives in 43.3 seconds, and the tail arrives in 42.6 seconds. The head of the rear strip S2 arrives in 34.8 seconds, and the tail arrives in 43.2 seconds.

[0087] Next, calculate the time difference between the head of the rear strip and the tail of the front strip reaching the point prone to rear-end collision accidents;

[0088] When the rear strip S2 arrives at the safety inspection before finishing rolling, the time difference between the head of the rear strip S2 and the tail of the front strip S1 is calculated to be -7.8 seconds.

[0089] Finally, the swing waiting time of the rear piece of steel is calculated based on the time difference between the head of the rear piece of steel and the tail of the front piece of steel reaching the accident-prone position and the safety distance.

[0090] According to the time difference of -7.8 seconds between the head of the rear strip S2 and the tail of the front strip S1, it is judged that there is a possibility of collision between the rear strip S2 and the front strip S1. The time difference is less than the minimum swing time. The swing time of the rear strip S2 is set to 10 seconds to adjust the overall production rhythm.

[0091] The embodiment of the present invention provides a production rhythm control method, which determines the possibility of collision by calculating the running diagram of the front and rear strips and the time to reach the safety checkpoint. If there is a possibility of collision, a safety distance is set, and the rhythm or speed control of the rear strip is adjusted to make the rear strip wait in the swing steel area, thereby avoiding the rear-end collision accident of the front and rear strips.

[0092] Those skilled in the art know that, in addition to realizing the system and its various devices, modules, and units provided by the present invention in a purely computer-readable program code, it is entirely possible to realize the same functions in the form of logic gates, switches, application-specific integrated circuits, programmable logic controllers, and embedded microcontrollers by logically programming the method steps. Therefore, the system and its various devices, modules, and units provided by the present invention can be considered as a hardware component, and the devices, modules, and units included therein for realizing various functions can also be regarded as structures within the hardware component; the devices, modules, and units for realizing various functions can also be regarded as both software modules for realizing the method and structures within the hardware component.

[0093] The above describes the specific embodiments of the present invention. It should be understood that the present invention is not limited to the above specific embodiments, and those skilled in the art can make various changes or modifications within the scope of the claims, which does not affect the essence of the present invention. In the absence of conflict, the embodiments of the present application and the features in the embodiments can be combined with each other arbitrarily.

Claims

1. A production rhythm control method, characterized in that: include: Step S1: Divide the rolling line into areas according to the layout of the process equipment, determine the anti-collision points, specify the safe operation check points, the safe spacing distance between the front and rear strips, and set the swing interval and the minimum swing time; Step S2: Calculate the time for the head and tail of the strip to reach the anti-collision point respectively; Step S3: Calculate the time difference between the head of the rear strip and the tail of the front strip reaching the anti-collision point; Step S4: Calculate the waiting time for the rear steel strip to swing according to the time difference between the head of the rear steel strip and the tail of the front steel strip reaching the anti-collision point and the safety distance; Step S5: Control the production rhythm according to the waiting time; The step S2 comprises: Step S2.1: When the front strip S1 reaches the flying shear position at the finishing entrance, calculate the first time T of the head of the front strip S1 reaching the anti-collision point according to Newton's equation of motion. head , while saving the first time T head ; Step S2.2: When the front strip S1 reaches the flying shear position at the finishing entrance, calculate the first time T of the tail of the front strip S1 reaching the anti-collision point according to Newton's motion equation. tail , while saving the first time T tail ; Step S2.3: When the rear strip S2 reaches the flying shear position at the finishing entrance, the second time T when the head of the rear strip S2 reaches the anti-collision point is calculated in the same manner as steps S2.1 and S2.

2. head The second time T when the tail of the rear strip S2 reaches the anti-collision point tail ; The step S4 comprises: Step S4.1: Determine the size of △t. If △t is not greater than 0, there will be no collision. Set the swing time T of the rear strip S2. osc 0, if it is greater than 0 and less than the safety time T s , T osc Set to T s , otherwise set the swing time T osc is △t; Step S4.2: Set the swing time T of the rear strip S2 osc Send to the basic automatic control system to execute swing steel waiting control on the rear strip S2; The step S1 comprises: Step S1.1: according to the rolling line equipment layout, the flying shear at the finishing rolling entrance is determined as a safety checkpoint, the pinch roller at the coiling entrance is used as an anti-collision point, and the middle roller area in front of the flying shear is set as a steel swing area; Step S1.2: Taking the safety checkpoint as the reference position and as the starting point for calculating the time for the strip to run to the anti-collision point, the distance between the finishing entrance flying shear, the anti-collision point and the safety checkpoint is determined according to the equipment layout; Step S1.3: Set the safety distance between the front and rear strips. In case of collision, consider the calculation error and set a minimum swing time T s ; The step S3 comprises: calculating the first time T of the front strip S1 tail and the second time T of the rear strip S2 head The difference △t.

2. A production rhythm control system, characterized in that: include: Module M1: Divide the rolling line into areas according to the layout of process equipment, determine anti-collision points, specify safe operation checkpoints, safe spacing between front and rear strips, and set the swing interval and minimum swing time; Module M2: Calculate the time for the head and tail of the strip to reach the anti-collision point respectively; Module M3: Calculate the time difference between the head of the rear strip and the tail of the front strip reaching the anti-collision point; Module M4: Calculate the waiting time for the rear piece of steel to swing according to the time difference between the head of the rear piece of steel and the tail of the front piece of steel reaching the anti-collision point and the safety distance; Module M5: Control the production rhythm according to the waiting time; The module M2 comprises: Module M2.1: When the front strip S1 reaches the flying shear position at the finishing entrance, calculate the first time T when the head of the front strip S1 reaches the anti-collision point according to Newton's equation of motion. head , while saving the first time T head ; Module M2.2: When the front strip S1 reaches the flying shear position at the finishing entrance, calculate the first time T when the tail of the front strip S1 reaches the anti-collision point according to Newton's motion equation tail , while saving the first time T tail ; Module M2.3: When the rear strip S2 reaches the flying shear position at the finishing entrance, the second time T of the head of the rear strip S2 reaching the anti-collision point is calculated in the same way as modules M2.1 and M2.

2. head The second time T when the tail of the rear strip S2 reaches the anti-collision point tail ; The module M4 comprises: Module M4.1: Determine the size of △t. If △t is not greater than 0, there will be no collision. Set the swing time T of the rear strip S2. osc 0, if it is greater than 0 and less than the safety time T s , T osc Set to T s , otherwise set the swing time T osc is △t; Module M4.2: Set the swing time T of the rear strip S2 osc Send to the basic automatic control system to execute swing steel waiting control on the rear strip S2; The module M1 comprises: Module M1.1: According to the layout of the rolling line equipment, the flying shear at the finishing rolling entrance is determined as the safety inspection point, the pinch roller at the coiling entrance is used as the anti-collision point, and the middle roller area in front of the flying shear is set as the swing steel area; Module M1.2: Take the safety checkpoint as the reference position and as the starting point for calculating the time for the strip to run to the anti-collision point. At the same time, determine the distance between the finishing entrance flying shear, the anti-collision point and the safety checkpoint according to the equipment layout; Module M1.3: Set the safety distance between the front and rear strips. In case of collision, consider the calculation error and set a minimum swing time T s ; The module M3 includes: calculating the first time T of the front strip S1 tail and the second time T of the rear strip S2 head The difference △t.

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