A tension roller group dynamic load distribution method based on slip mechanism

Abstract

The application discloses a tension roller group dynamic load distribution method based on a slip mechanism and particularly relates to the field of dynamic load distribution; the application establishes a model by calculating tension loss and actual tension values of tension roller inlets / outlets, combining elastic deformation and geometric parameters; a strip steel winding angle is divided into micro-arc segments, tension changes under a critical sliding state are analyzed, normal and tangential force balance equations are constructed, and the influence of friction and gravity is considered; according to limit tension amplification coefficients of each tension roller, total tension ratios are proportionally distributed, it is initially assumed that proportional factors of each roller are equal, a common proportional factor is solved through iteration, and tension differences of each roller are calculated; further, transmission power and torque are calculated, tension amplification, friction loss and bending loss are comprehensively considered, and the driving motor capacity is checked; if the limit is exceeded, the tension roller proportion of the upstream and downstream is adjusted, the tension difference of the over-limit roller is preferentially reduced, and step-by-step optimization is performed until the power and torque of all rollers meet the requirements.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of dynamic load distribution, and more particularly, to a tension roller set dynamic load distribution method based on a slip mechanism. BACKGROUND

[0002] In a continuous strip production process, dynamic load distribution of a tension roller set is a key technology to ensure stable operation of the strip and product quality; during commissioning, tension roller set control is mainly based on the speed of the outlet 1# tension roller as a benchmark, and other tension roller motors saturate the speed loop, and at the same time, the same torque ratio as the speed benchmark motor is given for torque control, to achieve the purpose of tension control and ideal strip yield strength

[0003] However, in actual use, it still has some disadvantages, such as the traditional load distribution method is often based on static analysis, and the friction and slip mechanism under dynamic conditions are not fully considered, resulting in unstable working state of the roller set, damage to the material and increase in energy consumption. SUMMARY

[0004] In order to overcome the above-mentioned defects of the prior art, the embodiments of the present application provide a tension roller set dynamic load distribution method based on a slip mechanism to solve the problems raised in the background art.

[0005] To achieve the above-mentioned purpose, the present application provides the following technical scheme:

[0006] Step A1: calculating the tension loss and the actual tension values at the inlet and outlet of the tension roller;

[0007] Step A2: dividing the wrapping angle of the strip on the tension roller into a plurality of micro-arc segments, performing force analysis on each micro-arc segment, and calculating the tension change under the critical slip state;

[0008] Step A3: according to the amplification coefficient of the limit tension of each tension roller, the tension ratio that needs to be expanded or reduced by the tension roller set is evenly distributed to each tension roller;

[0009] Step A4: calculating the required driving power and torque of each tension roller according to the tension difference borne by each tension roller, and checking according to the power and torque of the driving motor;

[0010] Step A5: if the power or torque of the tension roller exceeds the driving motor capacity, adjust the tension amplification ratio of the upstream and downstream tension rollers until the power and torque of all tension rollers meet the requirements.

[0011] Preferably, in step A1, when the strip is wrapped on the tension roller, elastic deformation and plastic deformation will occur inside the strip, resulting in tension loss, and the calculation method of the tension loss caused by elastic bending of the strip at the inlet and outlet of the tension roller is specifically:

[0012] wherein, represents the tension loss caused by the elastic bending of the strip at the inlet and outlet, represents the yield strength of the strip, h represents the thickness of the strip, b represents the width of the strip, R represents the bending radius of the strip, and is about 1.1-1.2 times the radius of the tension roller.

[0013] Preferably, in the step A2, the normal force of the strip wrapped on the tension roller needs to satisfy the centripetal force balance condition; the actual wrapping angle of the strip is evenly divided into n micro-arc segments, and for the i-th micro-arc segment, the normal force equation of the strip is:

[0014] wherein, represents the tension of the i-th micro-arc segment; represents the central angle corresponding to the i-th micro-arc segment, represents the difference between the tension close to the outlet side and the tension close to the inlet side on the i-th micro-arc segment, represents the normal pressure of the i-th micro-arc segment on the tension roller surface, represents the included angle between the i-th micro-arc segment and the perpendicular bisector, represents the mass of the i-th micro-arc segment, and g represents the acceleration of gravity, represents the movement speed of the strip, and R represents the radius of the tension roller;

[0015] For the inclined installation of the tension roller or the vertical movement component of the strip, the gravity changes the contact force between the strip and the tension roller, and affects the friction force, so the tangential force equation is:

[0016] wherein, represents the tension of the i-th micro-arc segment; represents the central angle corresponding to the i-th micro-arc segment, represents the difference between the tension close to the outlet side and the tension close to the inlet side on the i-th micro-arc segment, represents the friction force between the i-th micro-arc segment and the tension roller surface, represents the included angle between the i-th micro-arc segment and the perpendicular bisector, represents the mass of the i-th micro-arc segment, and g represents the acceleration of gravity, represents the movement speed of the strip, and R represents the radius of the tension roller.

[0017] Preferably, in the step A3, the tension roller group is composed of N tension rollers, according to the geometric position of the strip wrapped around each tension roller, the cross-sectional size of the strip, the speed of the unit, the acceleration and deceleration conditions, and the friction coefficient at each tension roller, the limit tension amplification coefficient of each roller under the current working condition is obtained ;

[0018] The calculation method of the ultimate tension amplification factor is specifically:

[0019] , wherein, represents the ultimate tension amplification factor, represents the actual exit tension of the strip on the tension roll after considering the tension loss, represents the actual entry tension of the strip on the tension roll after considering the tension loss, represents the tension loss caused by the elastic bending of the strip at the entry and exit;

[0020] The tension ratio that needs to be expanded or reduced by the tension roll set is evenly distributed to each tension roll according to the actual tension amplification capacity of each roll; it is assumed that the actual tension amplification ratio of each tension roll is equal to the ratio of the corresponding ultimate tension amplification factor in the initial calculation; that is: , wherein, , , , represents the proportional factor of the first, second, …, k, …, N tension rolls, represents the common proportional factor;

[0021] The calculation method of the total tension ratio of the tension roll set is specifically:

[0022] , wherein, represents the exit tension of the tension roll set, represents the entry tension of the tension roll set, , , , represents the proportional factor of the first, second, …, k, …, N tension rolls, represents the common proportional factor, and N represents the number of tension rolls, represents the ultimate tension amplification factor.

[0023] Preferably, in step A4, the required driving power of the kth tension roll is composed of three parts, which are the power required for tension amplification , the friction loss of the driving shaft , and the bending loss of the strip .

[0024] The calculation method of the power required for tension amplification is specifically:

[0025] , wherein, represents the power required for tension amplification, represents the tension change amount of the kth tension roll, denotes the running speed of the strip, denotes the mechanical transmission efficiency;

[0026] The calculation method of the transmission shaft friction loss is specifically:

[0027] wherein, denotes the transmission shaft friction loss, denotes the friction coefficient at the bearing of the tension roll, denotes the tension difference between the inlet and outlet of the tension roll, denotes the running speed of the strip, denotes the mechanical transmission efficiency;

[0028] The calculation method of the strip bending loss is specifically:

[0029] wherein, denotes the strip bending loss, denotes the yield strength, denotes the strip width, denotes the strip thickness, denotes the running speed of the strip, denotes the radius, denotes the mechanical transmission efficiency;

[0030] The transmission power required by the kth tension roll is:

[0031] wherein, denotes the transmission power required by the kth tension roll, denotes the power required by the tension amplification, denotes the transmission shaft friction loss, denotes the strip bending loss.

[0032] Preferably, in the step A5, when the power or torque required by one or more tension rolls exceeds the power or torque of the corresponding driving motor, the tension values at the inlet and outlet of the tension roll need to be adjusted according to the proportion of the excess of the tension roll, the surplus of the tension amplification capacity of the upstream and downstream tension rolls, and the surplus of the power and torque of the driving motor, so as to exert the capacity of the tension roll set as much as possible and meet the production requirements.

[0033] When the torque required by the kth tension roll exceeds the maximum torque provided by the driving motor, according to the calculation formula of the torque required by the tension roll, the main way to reduce the torque required by the current roll is to reduce the tension difference at the inlet and outlet of the current roll. At this time, it is necessary to adjust the outlet tension of the k-1th tension roll and the inlet tension of the k+1th tension roll; the outlet tension of the k-1th tension roll is reduced by and the inlet tension of the k+1th tension roll is increased by Set to 1, recalculate the required power and torque of each tension roller, and check, if the required torque of the kth tension roller still exceeds the maximum torque provided by the driving motor, continue to adjust the magnification ratio of the upstream and downstream tension rollers until the required power and torque of all tension rollers are met; if all upstream and downstream tension rollers have been adjusted, but the torque still does not meet the requirements, it is determined that the set tension roller group inlet and outlet tension values exceed the current equipment adjustment capability, and the process personnel adjust the inlet / outlet tension values according to the actual requirements of the upstream and downstream processes.

[0034] The technical effects and advantages of the present application are:

[0035] The present application realizes accurate checking and optimization adjustment of the tension roller group by establishing a tension loss model, a micro-arc segment force balance equation and a critical sliding condition, combining the limit tension magnification coefficient with the equipment capacity constraint, thereby improving the stability of the production process and the equipment life. BRIEF DESCRIPTION OF DRAWINGS

[0036] Figure 1 The present application is a method flowchart.

[0037] Figure 2 The present application is a force analysis diagram. DETAILED DESCRIPTION

[0038] The technical solutions in the embodiments of the present application will be described clearly and completely below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor are within the scope of protection of the present application.

[0039] Please refer to Figure 1 The present application provides a tension roller group dynamic load distribution method based on the slip mechanism, which comprises the following steps:

[0040] Step A1: calculate the tension loss and the actual tension values at the inlet and outlet of the tension roller;

[0041] In the step A1, when the strip is wrapped around the tension roller, elastic deformation and plastic deformation will occur inside the strip, resulting in tension loss. The calculation method of the tension loss caused by the elastic bending of the strip at the inlet and outlet of the tension roller is as follows:

[0042] wherein, represents the tension loss caused by the elastic bending of the strip at the inlet and outlet, The yield strength of the strip is represented by h, the thickness of the strip is represented by b, the width of the strip is represented by R, the bending radius of the strip is represented by a tension roller radius of about 1.1-1.2 times;

[0043] The tension loss affects the actual tension values at the inlet and outlet of the tension roller, and the calculation method of the actual tension value at the inlet of the tension roller is specifically:

[0044] , wherein The actual outlet tension of the strip on the tension roller is represented by considering the tension loss, The nominal outlet tension of the strip on the tension roller is represented by The tension loss caused by the elastic bending of the strip at the inlet and outlet is represented by

[0045] The calculation method of the actual tension value at the outlet of the tension roller is specifically:

[0046] , wherein The actual inlet tension of the strip on the tension roller is represented by considering the tension loss, The nominal inlet tension of the strip on the tension roller is represented by The tension loss caused by the elastic bending of the strip at the inlet and outlet is represented by

[0047] Step A2: The wrapping angle of the strip on the tension roller is divided into a plurality of micro-arc segments, and the force analysis of each micro-arc segment is carried out to calculate the tension change under the critical sliding state;

[0048] In the step A2, the normal force of the strip wrapped on the tension roller needs to satisfy the centripetal force balance condition; the actual wrapping angle is divided into n micro-arc segments, and for the i-th micro-arc segment, the normal force equation of the strip is:

[0049] , wherein The tension of the i-th micro-arc segment is represented by The central angle corresponding to the i-th micro-arc segment is represented by The difference between the tension on the outlet side and the tension on the inlet side of the i-th micro-arc segment is represented by The normal pressure of the i-th micro-arc segment on the tension roller surface is represented by The included angle between the i-th micro-arc segment and the perpendicular line is represented by The mass of the i-th micro-arc segment is represented by g, and the acceleration of gravity is represented by The movement speed of the strip is represented by R, and the radius of the tension roller is represented by

[0050] For the tension roller installed at an inclination or the vertical movement component of the strip, the gravity changes the contact force between the strip and the tension roller, and affects the friction force, and the tangential force equation is:

[0051] wherein, represents the tension of the i-th micro-arc segment; represents the central angle corresponding to the i-th micro-arc segment, represents the difference between the tension near the exit side and the tension near the entrance side on the i-th micro-arc segment, represents the frictional force between the i-th micro-arc segment and the tension roller surface, represents the included angle between the i-th micro-arc segment and the perpendicular bisector, represents the mass of the i-th micro-arc segment, g represents the gravitational acceleration, represents the movement speed of the strip, R represents the radius of the tension roller, and a represents the acceleration of the strip;

[0052] When the strip of the micro-arc segment and the tension roller are in a critical sliding state, according to the sliding friction law, the following relationship is satisfied:

[0053] wherein, represents the frictional force, represents the normal pressure of the i-th micro-arc segment on the tension roller surface;

[0054] the exit tension of the i-th micro-arc segment the entrance tension of the i+1-th micro-arc segment are equal, that is, the calculation method is specifically:

[0055]

[0056] wherein, represents the tension of the i+1-th micro-arc segment; represents the tension of the i-th micro-arc segment; represents the difference between the tension near the exit side and the tension near the entrance side on the i-th micro-arc segment;

[0057] the included angle between the i-th micro-arc segment and the perpendicular bisector the included angle between the i+1-th micro-arc segment and the perpendicular bisector has the following relationship:

[0058]

[0059] wherein, represents the included angle between the i+1-th micro-arc segment and the perpendicular bisector; represents the included angle between the i-th micro-arc segment and the perpendicular bisector; represents the included angle between the i-th micro-arc segment and the perpendicular bisector; represents the included angle between the i+1-th micro-arc segment and the perpendicular bisector;

[0060] The entry tension of the first micro-arc segment The back tension of the tension roll is equal, i.e.

[0061]

[0062] The finite difference calculation model of the tension roll ultimate tension amplification factor considering the elastic-plastic loss, centripetal force, gravity and acceleration / deceleration is obtained by combining (1), (2) and (3), i.e.

[0063] Specifically,

[0064]

[0065] In the formula,

[0066] is the coefficient of the entry tension in the equation of the i-th micro-arc segment, ;

[0067] is the constant term in the equation of the i-th micro-arc segment, ;

[0068] The coefficient matrix of the equation group (4) is obviously invertible, so the solution of the above problem can always be expressed as ; thus the front tension after considering the tension loss at the exit of the tension roll can be obtained;

[0069] wherein, represents the maximum front tension that can be provided by the tension roll at the entry when the back tension is T.

[0070] Step A3: according to the ultimate tension amplification factors of the tension rolls, the tension ratio that needs to be expanded or reduced by the tension roll set is evenly distributed to each tension roll;

[0071] In the step A3, the tension roll set consists of N tension rolls, according to the geometric position of the strip winding at each tension roll, the strip cross-sectional size, the speed of the unit, the acceleration / deceleration condition, and the friction coefficient at each tension roll, the ultimate tension amplification factor of each roll under the current working condition is obtained ;

[0072] The calculation method of the ultimate tension amplification factor is specifically as follows:

[0073] wherein, represents the ultimate tension amplification factor, represents the actual exit tension of the strip on the tension roll after considering the tension loss, represents the actual entry tension of the strip on the tension roll after considering the tension loss, Tension loss caused by the elastic bending of the strip at the entry and exit of the tension roll set;

[0074] The tension ratio that needs to be expanded or reduced by the tension roll set is evenly distributed to each tension roll according to the actual tension amplification capability of each roll; during initial calculation, it is assumed that the actual tension amplification ratio of each tension roll is equal to the ratio of the corresponding limit tension amplification coefficient; that is: , wherein, , , …, , …, is a proportional factor of the 1st, 2nd, …k…N tension roll, is a common proportional factor;

[0075] The calculation method of the total tension ratio of the tension roll set is specifically:

[0076] , wherein, is the tension at the exit of the tension roll set, is the tension at the entry of the tension roll set, , , …, , …, is a proportional factor of the 1st, 2nd, …k…N tension roll, is a common proportional factor, and N is the number of tension rolls, is a limit tension amplification coefficient;

[0077] The calculation formula of the tension roll set is solved to obtain the load distribution considering only the tension amplification capability of each tension roll, and the calculation method is specifically:

[0078] , wherein, is a common proportional factor, and N is the number of tension rolls, is the front tension at the exit considering the tension loss, is a reference tension, is a limit tension amplification coefficient;

[0079] According to the load distribution calculation formula of the tension roll tension amplification capability, the tension difference between the entry and exit of the kth tension roll can be calculated, and the calculation method is specifically:

[0080] , wherein, is the tension change amount of the kth tension roll, is a limit tension reduction coefficient, is a limit tension amplification coefficient, is a reference tension, is a common proportional factor.

[0081] Step A4: Calculate the required transmission power and torque of each tension roller based on the tension difference borne by each tension roller, and calibrate them based on the power and torque of the drive motor;

[0082] In step A4, the transmission power required by the k-th tension roller consists of three parts: the power required for tension amplification , transmission shaft friction loss , Strip bending loss ;

[0083] The calculation method of the power required for tension amplification is as follows:

[0084] ,in, Expressed as the power required for tension amplification, Expressed as the tension change of the k-th tension roller, Expressed as the strip running speed, Expressed as mechanical transmission efficiency;

[0085] The calculation method of transmission shaft friction loss is as follows:

[0086] ,in, Expressed as the transmission shaft friction loss, Expressed as the friction coefficient at the tension roller bearing, It is expressed as the tension difference between the inlet and outlet of the tension roller. Expressed as the strip running speed, Expressed as mechanical transmission efficiency;

[0087] The calculation method of strip bending loss is as follows:

[0088] ,in, Expressed as strip bending loss, Expressed as yield strength, Expressed as strip width, Expressed as strip thickness, Expressed as the strip running speed, Expressed as radius, Expressed as mechanical transmission efficiency;

[0089] Then the transmission power required for the kth tension roller is:

[0090] ,in, Expressed as the transmission power required for the k-th tension roller, Expressed as the power required for tension amplification, Expressed as the transmission shaft friction loss, Expressed as strip bending loss;

[0091] The torque required for the kth tension roller also consists of three parts: the torque required to overcome the inlet and outlet tension difference , the torque required to overcome the friction of the drive shaft , the torque required to overcome the bending deformation of the strip ;

[0092] The calculation method of the torque required to overcome the inlet and outlet tension difference is as follows:

[0093] ,in, It is the torque required to overcome the inlet and outlet tension difference. It is expressed as the tension change of the k-th tension roller, and R is the radius;

[0094] The calculation method for the torque required to overcome the friction of the drive shaft is as follows:

[0095] ,in, Indicates the torque required to overcome the friction of the drive shaft, Expressed as the friction coefficient at the tension roller bearing, It is expressed as the tension difference between the inlet and outlet of the tension roller. Expressed as radius;

[0096] The calculation method of the torque required to overcome the bending deformation of the strip is as follows:

[0097] ,in, Indicates the torque required to overcome the bending deformation of the strip. Expressed as yield strength, It is expressed as the strip width, and h is expressed as the strip thickness;

[0098] The maximum working torque required for the normal operation of the kth tension roller is:

[0099] ,in, It is expressed as the maximum working torque required for the normal operation of the k-th tension roller. It is the torque required to overcome the inlet and outlet tension difference. Indicates the torque required to overcome the friction of the drive shaft, Indicates the torque required to overcome the bending deformation of the strip;

[0100] The tension load distribution calculation calculates the tension at the inlet and outlet of each tension roller, substituting it into the power and torque required for each tension roller and comparing it with the power and torque of the corresponding drive motor. Load distribution is complete when the power and torque required by the tension roller are both less than the power and torque of the corresponding drive motor.

[0101] Step A5: If the power or torque of any tension roller exceeds the capacity of the drive motor, adjust the tension amplification ratio of the upstream and downstream tension rollers until the power and torque of all tension rollers meet the requirements.

[0102] In step A5, when the power or torque required by one or more tension rollers exceeds the power or torque of the corresponding drive motor, the tension values ​​at the inlet and outlet of the tension rollers need to be adjusted based on the proportion of the excess power or torque of the tension rollers, the margin of tension amplification capacity of the upstream and downstream tension rollers, and the margin of power and torque of the drive motors, so as to maximize the capacity of the tension roller group and meet production requirements.

[0103] When the torque required by the k-th tension roller exceeds the maximum torque provided by the drive motor, according to the calculation formula of the torque required by the tension roller, the main way to reduce the torque required by the current roller is to reduce the tension difference between the inlet and outlet of the current roller. At this time, it is necessary to adjust the outlet tension of the k-1 tension roller and the inlet tension of the k+1 tension roller. and the k+1th tension roller Set it to 1, recalculate the power and torque required for each tension roller, and perform a check. If the torque required for the kth tension roller still exceeds the maximum torque provided by the drive motor, continue to adjust the amplification ratio of the upstream and downstream tension rollers until the power and torque required for all tension rollers meet the requirements; if all upstream and downstream tension rollers have been adjusted, but the torque still does not meet the requirements, it is determined that the set inlet and outlet tension values ​​of the tension roller group exceed the adjustment capacity of the current equipment. The process personnel adjust the inlet / outlet tension values ​​according to the actual needs of the upstream and downstream processes.

[0104] Finally: The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A method for dynamic load distribution of a tension roller group based on a slipping mechanism, characterized in that: include: Step A1: Calculate the tension loss and the actual tension values ​​at the entrance and exit of the tension roller; Step A2: Divide the wrapping angle of the strip on the tension roller into multiple micro-arc segments, perform force analysis on each micro-arc segment, and calculate the tension change under the critical sliding state; By combining the comprehensive force equations of n micro-arc segments of the strip wrapped on the tension roller, a finite difference calculation model for the ultimate tension amplification coefficient of the tension roller is obtained, which takes into account elastic-plastic loss, centripetal force, gravity, and acceleration and deceleration conditions: ,in, Expressed as the coefficient matrix of the difference equation system, is represented as an array of unknown terms in a system of difference equations, An array of constant terms expressed as a system of difference equations; , where N is the number of tension rollers, Expressed as the coefficient of the entrance tension in the equation of the i-th micro-arc segment, ,in, Expressed as the sliding friction coefficient, It is represented as the central angle corresponding to the i-th micro-arc segment; ,in, Expressed as the entrance tension of the i-th micro-arc segment; It is expressed as the difference between the outlet tension and the inlet tension on the i-th micro-arc segment; ,in, Expressed as the constant term in the equation of the i-th micro-arc segment, , v represents the strip running speed, is represented by radius, g is represented by gravitational acceleration, It is expressed as the angle between the i-th micro-arc segment and the perpendicular bisector, and a is the acceleration of the strip; Expressed as the coefficient of the entrance tension in the first micro-arc segment equation, ; It is expressed as the entrance tension of the first micro-arc segment; The coefficient matrix of the established finite difference equation system is reversible, and the solution of the established difference equations can be expressed as: ,in, is represented as an array of unknown terms in a system of difference equations, Expressed as the inverse matrix of the coefficient matrix of the difference equation system, An array of constant terms expressed as a system of difference equations; Solutions of difference equations The last item It is the outlet tension of the last micro-arc segment, that is, the actual outlet tension of the strip on the tension roller after considering the tension loss. ; Step A3: Distributing the tension ratio required to be increased or decreased by the tension roller group to each tension roller evenly according to the limit tension amplification coefficient of each tension roller; Step A4: Calculating the required transmission power and torque of each tension roller based on the tension difference borne by each tension roller, and calibrating the calculation based on the power and torque of the drive motor; Step A5: If the power or torque of any tension roller exceeds the capacity of the drive motor, adjust the tension amplification ratio of the upstream and downstream tension rollers until the power and torque of all tension rollers meet the requirements.

2. The method for dynamic load distribution of a tension roller group based on a slipping mechanism according to claim 1, characterized in that: In step A1, when the steel strip is wrapped around the tension roller, elastic and plastic deformations will occur inside the steel strip, resulting in tension loss. The calculation method for the tension loss caused by elastic bending of the steel strip at the inlet and outlet of the tension roller is as follows: ,in, It is expressed as the tension loss caused by elastic bending of the strip at the entrance and exit. It is expressed as the yield strength of the strip, h is expressed as the thickness of the strip, b is expressed as the width of the strip, and R is expressed as the bending radius of the strip, which is approximately 1.1 to 1.2 times the radius of the tension roller.

3. The method for dynamic load distribution of a tension roller group based on a slipping mechanism according to claim 2, characterized in that: After considering the tension loss, the actual entrance tension of the strip on the tension roller is: ,in, It is the actual entrance tension of the strip on the tension roller after considering the tension loss. Expressed as the nominal inlet tension of the strip on the tension roller, It is expressed as the tension loss caused by elastic bending of the strip at the entrance and exit; Similarly, the actual exit tension of the strip on the tension roller after considering the tension loss is: ,in, It is the actual exit tension of the strip on the tension roller after considering the tension loss. Expressed as the nominal exit tension of the strip on the tension roller, It is expressed as the tension loss caused by elastic bending of the strip at the entrance and exit.

4. The method for dynamic load distribution of a tension roller group based on a slipping mechanism according to claim 1, characterized in that: In step A2, the normal force on the steel strip wrapped around the tension roller must satisfy the centripetal force balance condition. The steel strip within the actual wrap angle is evenly divided into n micro-arc segments. For the i-th micro-arc segment, the normal force equation for the steel strip is: ,in, Expressed as the entrance tension of the i-th micro-arc segment; It is represented as the central angle corresponding to the i-th micro-arc segment, It represents the difference between the outlet tension and the inlet tension on the i-th micro-arc segment, It is expressed as the positive pressure of the i-th micro-arc segment on the tension roller surface, It is expressed as the angle between the i-th micro-arc segment and the perpendicular bisector, is the mass of the i-th micro-arc segment, g is the acceleration due to gravity, It is expressed as the speed of the strip, and R is the radius of the tension roller; For the vertical motion component of the inclined tension roller or strip, gravity changes the contact force between the strip and the tension roller, affecting the friction force. The tangential force equation is: ,in, Expressed as the entrance tension of the i-th micro-arc segment; It is represented as the central angle corresponding to the i-th micro-arc segment, It is expressed as the difference between the outlet tension and the inlet tension on the i-th micro-arc segment, represents the friction force between the i-th micro-arc segment and the tension roller surface, It is expressed as the angle between the i-th micro-arc segment and the perpendicular bisector, is the mass of the i-th micro-arc segment, g is the acceleration due to gravity, It is expressed as the speed of the strip, R is the radius of the tension roller, and a is the acceleration of the strip; When the strip steel in the micro-arc segment and the tension roller are in a critical sliding state, according to the sliding friction law, the following relationship is satisfied: ,in, Expressed as friction, It is expressed as the positive pressure of the i-th micro-arc segment on the tension roller surface, Expressed as the coefficient of sliding friction.

5. The method for dynamic load distribution of a tension roller group based on a slipping mechanism according to claim 4, characterized in that: When the strip steel and the tension roller of the micro-arc segment are in a critical sliding state, the comprehensive force of the micro-arc segment is: ； ,in, Expressed as the sliding friction coefficient, It is represented as the central angle corresponding to the i-th micro-arc segment, Expressed as the entrance tension of the i-th micro-arc segment, It is expressed as the difference between the outlet tension and the inlet tension on the i-th micro-arc segment, Expressed as the mass of the i-th micro-arc segment, It is expressed as the speed of the strip, R is the radius of the tension roller, g is the acceleration due to gravity, It is expressed as the angle between the i-th micro-arc segment and the perpendicular bisector, and a is the acceleration of the strip; The outlet tension of the i-th micro-arc segment The entrance tension of the i+1th micro-arc segment Equal, that is, the calculation method is: ,in, It is expressed as the entrance tension of the i+1th micro-arc segment; Expressed as the entrance tension of the i-th micro-arc segment; It is expressed as the difference between the outlet tension and the inlet tension on the i-th micro-arc segment; The angle between the i-th micro-arc segment and the perpendicular bisector The angle between the i+1th micro-arc segment and the perpendicular bisector There are the following relationships: ,in, It is expressed as the angle between the i+1th micro-arc segment and the perpendicular bisector; It is expressed as the angle between the i-th micro-arc segment and the perpendicular bisector; It is expressed as the angle between the i-th micro-arc segment and the perpendicular bisector; It is expressed as the angle between the i+1th micro-arc segment and the perpendicular bisector.

6. The method for dynamic load distribution of a tension roller group based on a slipping mechanism according to claim 1, characterized in that: In step A3, the tension roller group consists of N tension rollers. According to the geometric position of the strip wrapped at each tension roller, the cross-sectional size of the strip, the speed of the unit, the acceleration and deceleration conditions, and the friction coefficient at each tension roller, the limit tension amplification coefficient of each roller under the current working condition is obtained. ; The calculation method of the ultimate tension amplification factor is as follows: ,in, Expressed as the ultimate tension amplification factor, It is the actual exit tension of the strip on the tension roller after taking into account the tension loss. It is the actual entrance tension of the strip on the tension roller after considering the tension loss. It is expressed as the tension loss caused by elastic bending of the strip at the entrance and exit; The tension ratio that needs to be increased or decreased by the tension roller group is evenly distributed to each tension roller according to the actual tension amplification capacity of each roller. In the initial calculation, it is assumed that the ratio of the actual tension amplification ratio of each tension roller is equal to the corresponding limit tension amplification coefficient; that is: ,in, 、 ,……, ,……, Expressed as the proportional factors of the 1st, 2nd, ...k...N tension rollers, Expressed as a common scale factor.

7. The method for dynamic load distribution of a tension roller group based on a slipping mechanism according to claim 1, characterized in that: In step A4, the transmission power required by the k-th tension roller consists of three parts: the power required for tension amplification , transmission shaft friction loss , Strip bending loss ; The calculation method of the power required for tension amplification is as follows: ,in, Expressed as the power required for tension amplification, Expressed as the tension change of the k-th tension roller, Expressed as the strip running speed, Expressed as mechanical transmission efficiency; The calculation method of transmission shaft friction loss is as follows: ,in, Expressed as the transmission shaft friction loss, Expressed as the friction coefficient at the tension roller bearing, It is expressed as the tension difference between the inlet and outlet of the tension roller. Expressed as the strip running speed, Expressed as mechanical transmission efficiency; The calculation method of strip bending loss is as follows: ,in, Expressed as strip bending loss, Expressed as yield strength, Expressed as strip width, Expressed as strip thickness, Expressed as the strip running speed, Expressed as radius, Expressed as mechanical transmission efficiency; The calculation method of the torque required to overcome the inlet and outlet tension difference is as follows: ,in, It is the torque required to overcome the inlet and outlet tension difference. It is expressed as the tension change of the k-th tension roller, and R is the radius; The tension conditions at the inlet and outlet of each tension roller obtained from the tension load distribution calculation are substituted into the power and torque required for each tension roller and compared with the power and torque of the corresponding drive motor. When the power and torque required by the tension roller are both less than the power and torque of the corresponding drive motor, the load distribution is completed.

8. The method for dynamic load distribution of a tension roller group based on a slipping mechanism according to claim 1, characterized in that: In step A5, when the power or torque required by one or more tension rollers exceeds the power or torque of the corresponding drive motor, the tension values ​​at the inlet and outlet of the tension rollers need to be adjusted based on the proportion of the excess power or torque of the tension rollers, the margin of tension amplification capacity of the upstream and downstream tension rollers, and the margin of power and torque of the drive motors; The torque required by the kth tension roller exceeds the maximum torque provided by the drive motor. According to the calculation formula of the torque required by the tension roller, the main way to reduce the torque required by the current roller is to reduce the tension difference between the inlet and outlet of the current roller. At this time, it is necessary to adjust the outlet tension of the k-1 tension roller and the inlet tension of the k+1 tension roller; respectively adjust the outlet tension of the k-1 tension roller and the inlet tension of the k+1 tension roller. and the k+1th tension roller Set it to 1, recalculate the power and torque required for each tension roller, and perform a check.

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