Optimization method suitable for circle shear process parameters during strip steel deviation

Abstract

The invention discloses an optimization method suitable for circle shear process parameters during strip steel deviation, which comprises the following steps: A) confirming strip steel deviation types, and calculating deviation quantity in the corresponding deviation types; whether transverse component velocity exists in the shearing process of the disc shear or not is judged; b) calculating the additional acting force generated when the strip steel deviates and the additional shearing force of the circle shear; and C) adjusting the clearance amount of the circle shear.

Description

Technical Field

[0001] The invention belongs to the technical field of shearing of rolled steel strips in metal rolling, and in particular relates to an optimization method for disc shearing process parameters when the steel strips deviate. Background Art

[0002] As an important part of the packaging industry, metal packaging has developed rapidly in recent years due to its safety, environmental protection, airtight and opaque, long shelf life and other characteristics. Among them, tinplate has a great advantage in the packaging industry due to its non-toxic, corrosion-resistant, high strength, good ductility and other characteristics. In addition, with the growth of market demand, users have higher and higher requirements for the surface quality of tinplate while requiring the coating, corrosion resistance and other performance of tinplate. Therefore, while improving the production capacity of the unit, the surface quality of tinplate should also be improved. The edge quality of tinplate, as one of the important indicators of the surface quality of tinplate, not only affects the quality of the tinplate finished product, but also affects the stability of the unit operation. In order to ensure the centering of the shearing process of the disc shear and the stability of the strip tension, a pinch roller with a deviation correction function is arranged at the front end of the disc shearing process. However, due to the limited deviation correction capacity, the strip will still be subject to the additional force generated by the deviation of the strip during the disc shearing process, thus changing the stress state of the strip during the shearing process. However, based on the existing shearing process, the shearing capacity of the disc shear is exceeded, resulting in problems such as edge sticking and clogging of the strip during the shearing process.

[0003] In response to the problem of disc shear deviation during shearing, Chinese patent document with application number 202111527284.6 provides a control method and system to prevent the shear feed plate of a double-sided shear from deviating, and proposes a method for controlling the acceleration and speed of the pinch roller. However, there are many factors that cause the disc shear to deviate, and this method cannot comprehensively control the deviation of the strip.

[0004] The Chinese patent document with application number 202021189280.2 provides a double-sided shear pinch roller with a synchronous shaft, which realizes the synchronous rotation of the pinch roller of the double-sided shear through a synchronous motor. It is difficult for this device to avoid the deviation of the strip due to transmission errors.

[0005] The Chinese patent document with application number 201510639744.2 provides a strip edge burr control method suitable for a disc shear of a rewinding unit, which controls the strip edge burr defects by optimizing the disc shear gap, overlap, and tension, but does not involve a method for adjusting the shearing process parameters when the strip deviates.

[0006] The Chinese patent document with application number 201720012258.2 provides an automatic gap adjustment control system and a screw transmission structure, which improve the stability of gap adjustment for disc shears, but does not propose a control mechanism for strip shearing.

[0007] The Chinese patent document with application number 201610755256.2 provides a disc shear overlap adjustment mechanism and an adjustment method, proposes a disc shear overlap adjustment mechanism and an adjustment method of the mechanism, but does not propose a method for adjusting process parameters when the strip deviates. Summary of the invention

[0008] The technical problem to be solved by the present invention is to solve the shearing quality problems such as sticking and blocking caused by the strip deviation after the tinplate passes through the pinch rollers, further improve the operating speed of the unit and the edge cutting quality of the strip, and provide a set of optimization methods for the disc shearing edge process parameters suitable for the strip deviation based on the existing disc shearing edge.

[0009] The technical problem to be solved can be implemented through the following technical solutions.

[0010] A method for optimizing process parameters of a disc shear when strip steel deviates is characterized by comprising the following steps:

[0011] A) Confirm the strip deviation type and calculate the deviation amount in the corresponding deviation type; determine whether there will be a transverse speed component during the shearing process of the disc shear;

[0012] B) Calculate the additional force generated when the strip deviates and the additional shear force of the disc shear;

[0013] C) Adjust the clearance of the disc shear.

[0014] Furthermore, the deviation type of the strip in step A) includes local deviation or overall deviation.

[0015] Further, step A) includes the following sub-steps:

[0016] A1) When there is local deviation, compare whether the deviation amount under the action of the deviation correction roller is not less than the deviation amount of the strip. If the condition is met, the disc shear will shear normally; if the condition is not met, the difference between the two is defined as the deviation amount Δδ;

[0017] A2) When the whole strip is deviated, the strip deviation angle Δθ (°) is calculated according to the following formula:

[0018]

[0019] Among them, L jy is the distance from the pinch roller to the disc shear;

[0020] L jdy It is the distance between the center line of the strip, the center line of the pinch roller and the intersection of the axis of the circular shear.

[0021] Furthermore, in step A1), the following calculation formula is used:

[0022]

[0023] Among them, L jp is the deviation correction amount under the action of the deviation correction roller (mm);

[0024] P j is the clamping force of the pinch roller (N);

[0025] L j is the length of the pinch roller (mm);

[0026] b jp is the strip deviation position (mm);

[0027] t is the deviation time (s);

[0028] ρ is the density of the strip (kg / mm 3 );

[0029] b is the strip width (mm);

[0030] h is the strip thickness (mm);

[0031] l dj is the length of the strip in the contact area between the strip and the pinch roller (mm);

[0032] x is the coordinate of the strip deviation position.

[0033] Further, step B) comprises the following sub-steps:

[0034] B1) Calculate the correcting force F generated by the correcting function of the pinch roller when local deviation occurs. jp (N), the calculation formula is as follows:

[0035]

[0036] Where: P j is the clamping force of the pinch roller (N);

[0037] L j is the length of the pinch roller (mm);

[0038] Δδ is the difference between the deviation amount under the action of the deviation correction roller and the deviation amount of the strip;

[0039] x is the coordinate of the strip deviation position;

[0040] B2) When calculating the overall deviation, the deviation force F generated by the velocity component PP (N); the calculation formula is as follows:

[0041]

[0042] Where ρ is the strip density (kg / mm 3 );

[0043] b is the strip width (mm);

[0044] h is the strip thickness (mm);

[0045] V-strip running speed (mm / s);

[0046] Δθ is the strip deviation angle (°);

[0047] l dy is the contact length of the disc shear zone (mm);

[0048] B3) Obtain the friction coefficient μ between the strip and the cutter disc, and calculate the additional shear force ΔP between the strip and the disc shear caused by the correction force generated by the correction roller. jp (N); Additional shear force ΔP between the strip and the disc shear generated by the running speed of the strip pp (N); and the additional shear force ΔP between the strip and the disc shear generated by the combined effect of the two conditions fj (N); the calculation formula is as follows:

[0049]

[0050] Further, step C) includes the following sub-steps:

[0051] C1) Obtain the disc shear gap adjustment accuracy d (mm), set the disc shear accuracy adjustment step k, then the disc shear gap adjustment amount Δψ=kd;

[0052] C2) Obtain the initial gap ψ0 of the disc shear during the shearing process, the wear depth influence coefficient λ; the total lateral wear depth w of the blade during the i-th shearing i (mm); Maximum wear depth w during the blade's service life max (mm); wear degree influence index c; ultimate strength of strip steel σ b (MPa); δ elongation of the strip; thickness of the strip h (mm); inclination angle a of the blade qx (°); The influence coefficient η of the blade lateral wear depth on the gap amount, calculate the initial shear force P0 during the strip shearing process, the shear force P after the i-th gap adjustment i , and the shear force difference ΔP; the calculation formula is as follows:

[0053]

[0054] C3) Determine whether the change in shear force after the disc shear gap is adjusted is greater than the additional shear force. If the condition is met, adjust the original set gap ψ0 of the disc shear to ψ=ψ0-Δψ. If not, set Δψ=Δψ+kd and return to step C2 until the condition is met.

[0055] The method for optimizing the process parameters of the disc shear when the strip deviates using the above-mentioned technical solution has the following advantages and beneficial effects: through the online real-time adjustment of the process parameters of the disc shear, the quality defect of the strip edge sticking caused by the strip deviation is reduced, and the stability of the strip operation and the edge quality during the strip electroplating process are improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0056] Figure 1 This is a schematic diagram of the strip steel partially running to the left;

[0057] Figure 2 This is a schematic diagram of the local right deviation of the strip steel;

[0058] Figure 3 This is a schematic diagram of the overall left deviation of the strip steel;

[0059] Figure 4 This is a schematic diagram of the overall right deviation of the strip steel;

[0060] Figure 5 This is the force diagram of the normal shearing process of the disc shear;

[0061] Figure 6 This is a schematic diagram of the shear force of the disc shear when the strip runs off;

[0062] Figure 7 Schematic diagram of the overall calculation process of the disc shear gap. DETAILED DESCRIPTION

[0063] The present invention comprehensively considers the structure of the disc shear and the pinch roller device, combines the existing pinch roller and disc shear shearing process parameters and methods, and establishes the force conditions of the disc shear under different deviation conditions. On this basis, a method for optimizing the process parameters of a disc shear when the strip is deviating is established. Through this evaluation method, it is possible to solve the problems of shearing sticking caused by the deviation of the strip during the shearing process. The method for optimizing the process parameters of a disc shear when the strip is deviating described in the present invention mainly includes the following three parts: strip deviation analysis, strip deviation shear force calculation method, and disc shear shearing process parameter adjustment method. In order to achieve the above purpose, the present invention adopts the following execution steps:

[0064] A) Strip deviation can be divided into two situations: the first is local deviation, such as Figure 1 , Figure 2 As shown; the second is overall deviation, such as Figure 3 , Figure 4 As shown. To this end, the deviation amount in two cases is calculated respectively according to the influence of deviation on the force of the disc shear during shearing process.

[0065] A1) For the first case, the deviation can be corrected by the correction roller. First, the deviation amount L of the strip is obtained. pp (mm), calculate the deviation correction amount L under the action of the deviation correction roller jp (mm). Obtain the clamping force P of the pinch roller j (N); Pinch roller body length L j (mm); Strip deviation position b jp (mm); deviation time t (s); strip density ρ (kg / mm 3 ); strip width b (mm); strip thickness h (mm); strip length l in the contact area between the strip and the pinch roller dj (mm); strip deviation position coordinate x. The calculation formula is as follows:

[0066]

[0067] A2) Determine L jp -L pp ≥0 is true. If the condition is met, the disc shear will not produce deviation during the shearing process, and the disc shear will shear normally; if the condition is not met, the deviation is Δδ (mm); the calculation formula is as follows:

[0068] Δδ=L jp -L pp

[0069] A3) For the second case, the strip will always be beveled during the shearing process. At this time, the pinch roller is between the deviation center line, and no correction force is added to the pinch roller. However, there will be a lateral component speed during the shearing process of the disc shear, which will also cause additional force in the shearing process. Get the distance L from the pinch roller to the disc shear jy (mm); Get the distance L between the center line of the strip, the center line of the pinch roller and the intersection of the axis of the circular shear jdy , (mm), calculate its deviation angle Δθ (°); the calculation formula is as follows:

[0070]

[0071] B) Calculate the additional force caused by the overall deviation of the strip, such as Figure 6 As shown, along with additional shear forces.

[0072] B1) Calculate the correcting force F generated by the pinch roller correcting function when the first strip is running off jp(N), the calculation formula is as follows:

[0073]

[0074] B2) Obtain the running speed V (mm / s) of the strip steel; the contact length l of the disc shearing zone dy (mm); Calculate the deviation force F generated by the velocity component when the strip runs as a whole in the second case PP (N). The calculation formula is as follows:

[0075]

[0076] B3) Obtain the friction coefficient μ between the strip and the cutter disc, and calculate the additional shear force ΔP between the strip and the disc shear caused by the correction force generated by the correction roller. jp (N); Additional shear force ΔP between the strip and the disc shear generated by the running speed of the strip pp (N); and the additional shear force ΔP between the strip and the disc shear generated by the combined effect of the two conditions fj (N). The calculation formula is as follows:

[0077]

[0078] C) The essential impact of strip deviation on the shearing process of the disc shear is to change the size of the disc shear shearing force. The disc shearing force is actually the force generated by the elastic-plastic deformation of the strip. Therefore, it actually changes the elastic-plastic deformation process of the strip during the disc shearing process, causing the quality problem of the shearing of the strip edge. The disc shearing process parameters include the gap, overlap and the inclination angle of the cutter disc. Generally, the overlap and inclination angle are not adjusted, and only the gap of the disc shear is adjusted.

[0079] C1) Obtain the disk shear gap adjustment accuracy d (mm), set the disk shear accuracy adjustment step k, then the disk shear gap adjustment amount Δψ = kd.

[0080] C2) Obtain the initial gap ψ0 of the disc shear during the shearing process, the wear depth influence coefficient λ; the total lateral wear depth w of the blade during the i-th shearing i (mm); Maximum wear depth w during the blade's service life max (mm); wear degree influence index c; ultimate strength of strip steel σ b (MPa); δ elongation of the strip; thickness of the strip h (mm); inclination angle a of the blade qx (°); Disk shear gap adjustment Δψ (mm); The influence coefficient η of the blade lateral wear depth on the gap, calculate the initial shear force P0 during the strip shearing process, the shear force P after the i-th gap adjustment i, and the shear force difference ΔP; the calculation formula is as follows:

[0081]

[0082] C3) Determine ΔP ≥ ΔP fj Whether it is established, that is, whether the change in shear force after the disc shear gap is adjusted is greater than the additional shear force. If the condition is met, the original set gap ψ0 of the disc shear is adjusted to ψ=ψ0-Δψ. If it is not met, set Δψ=Δψ+kd and return to step C2 until the condition is met.

[0083] The present invention is applicable to the method for optimizing the process parameters of the disc shear when the strip is deviated. The overall calculation flow chart is as follows: Figure 7 shown.

[0084] The application of the method for optimizing process parameters of a circular shear when strip steel deviates according to the present invention will be further specifically described below in conjunction with the accompanying drawings and embodiments.

[0085] Embodiment 1:

[0086] A) This embodiment assumes that both of the two deviation situations of the strip steel occur. Therefore, the deviation amount in the two situations is calculated respectively according to the influence of the deviation situation on the force of the shearing process of the disc shear.

[0087] A1) For the deviation in the first case, the deviation can be corrected by the correction roller. First, the deviation of the strip is 6mm, and the deviation correction under the action of the correction roller is calculated to be 0.26mm. The clamping force of the pinch roller is 20N; the roller length of the pinch roller is 1500mm; the deviation time is 2s; the strip density is 7.85*10 -6 kg / mm 3 ; Strip width 800mm; Strip thickness 0.55mm; Strip length in the contact area between the strip and the pinch roller 1.5mm.

[0088] A2) At this time L jp -L pp ≤0, the deviation when the disc shear is cutting is 5.74mm.

[0089] A3) For the second case, the strip will always be beveled during the shearing process. At this time, the pinch roller is between the deviation center line, and no correction force is added to the pinch roller. However, there will be a lateral component of speed during the shearing process of the disc shear, which will also cause additional force during the shearing process. The distance from the pinch roller to the disc shear is 4000mm; the distance between the intersection of the strip center line, the pinch roller center line and the disc shear axis is 8mm, and the deviation angle is calculated as 2*10 -3 °.

[0090] B) Calculate the additional force caused by the overall deviation of the strip, such as Figure 6 As shown, along with additional shear forces.

[0091] B1) Calculate the first type of strip deviation caused by the pinch roller correction function 3.2*10 -4 N.

[0092] B2) Get the running speed of the strip steel 5*10 3 mm / s; the contact length of the disc shear zone is 0.5mm; the deviation force caused by the velocity component when the strip runs as a whole in the second case is calculated to be 172.7N.

[0093] B3) Obtain the friction coefficient between the strip and the cutter disc as 0.15, and calculate the additional shear force between the strip and the disc shear as 4.8*10 -5 N; the additional shear force between the strip and the disc shear is 25.91N caused by the running speed of the strip; and the additional shear force between the strip and the disc shear is 25.91N caused by the combined effect of the two situations.

[0094] C) The essential impact of strip deviation on the shearing process of the disc shear is to change the size of the disc shear shearing force. The disc shearing force is actually the force generated by the elastic-plastic deformation of the strip. Therefore, it actually changes the elastic-plastic deformation process of the strip during the disc shearing process, causing the quality problem of the shearing of the strip edge. The disc shearing process parameters include the gap, overlap and the inclination angle of the cutter disc. Generally, the overlap and inclination angle are not adjusted, and only the gap of the disc shear is adjusted.

[0095] C1) Get the disc shear gap adjustment accuracy 5*10 -3 mm, set the disc shear precision adjustment step size to 1, then the disc shear gap adjustment amount is 5*10 -3 mm.

[0096] C2) Obtain the initial gap of the disc shear during shearing: 0.06 mm; wear depth influence coefficient: 1.2; total lateral wear depth of the blade during the i-th shearing: 0.1 mm; maximum wear depth within the service life of the blade: 10 mm; wear degree influence index: 1.3; ultimate strength of the strip: 530 MPa; elongation of the strip: 0.22; thickness of the strip: 0.55 mm; inclination angle of the blade: 2.45*10 -3 °; Disk shear clearance adjustment 5*10 -2 mm; the influence coefficient of the lateral wear depth of the blade on the gap is 1.1. The initial shear force in the strip shearing process is 34289N, the shear force after the first gap adjustment (adjusted to 0.55mm) is 34213N, and the shear force difference is 76N.

[0097] C3) It is judged that 76>25.91 at this time, that is, the shear force change after the disc shear gap is adjusted is greater than the additional shear force, and the original set gap ψ0 of the disc shear is adjusted to ψ=0.055mm.

[0098] Embodiment 2:

[0099] A) This embodiment assumes that the strip steel has the second case where the strip steel is deviated as a whole. Therefore, the deviation amount in the second case is calculated based on the influence of the deviation situation on the force of the shearing process of the disc shear. (This embodiment does not involve steps A1 and A2)

[0100] A3) For the second case, the strip will always be beveled during the shearing process. At this time, the pinch roller is between the deviation center line. There is no additional correction force on the pinch roller. However, there will be a lateral component of speed during the shearing process of the disc shear, which will also cause additional force during the shearing process. The distance from the pinch roller to the disc shear is 4000mm; the distance between the center line of the strip and the intersection of the center line of the pinch roller and the axis of the disc shear is 10mm, and the deviation angle is calculated as 2.5*10 -3 °.

[0101] B) Calculate the additional force caused by the overall deviation of the strip, such as Figure 6 As shown, and additional shear force. (This embodiment does not involve step B1)

[0102] B2) Get the strip density 7.85*10 -6 kg / mm3; strip width 1000mm; strip thickness 0.55mm; strip running speed 1*10 4 mm / s; the contact length of the disc shear zone is 0.8mm; the deviation force caused by the velocity component when the strip runs as a whole in the second case is calculated to be 1079.3N.

[0103] B3) The friction coefficient between the strip and the cutter disc is obtained as 0.15, and based on the correcting force generated by the correcting roller, the additional shear force between the strip and the disc shear generated by the running speed of the strip is calculated as 161.9N.

[0104] C) The essential impact of strip deviation on the shearing process of the disc shear is to change the size of the disc shear shearing force. The disc shearing force is actually the force generated by the elastic-plastic deformation of the strip. Therefore, it actually changes the elastic-plastic deformation process of the strip during the disc shearing process, causing the quality problem of the shearing of the strip edge. The disc shearing process parameters include the gap, overlap and the inclination angle of the cutter disc. Generally, the overlap and inclination angle are not adjusted, and only the gap of the disc shear is adjusted.

[0105] C1) Get the disc shear gap adjustment accuracy 5*10 -3mm, set the disc shear precision adjustment step size to 1, then the disc shear gap adjustment amount is 5*10 -3 mm.

[0106] C2) Obtain the initial gap of the disc shear during shearing: 0.06 mm; wear depth influence coefficient: 1.2; total lateral wear depth of the blade during the i-th shearing: 0.1 mm; maximum wear depth within the service life of the blade: 10 mm; wear degree influence index: 1.3; ultimate strength of the strip: 530 MPa; elongation of the strip: 0.22; thickness of the strip: 0.55 mm; inclination angle of the blade: 2.45*10 -3 °; Disk shear clearance adjustment 5*10 -3 mm; the influence coefficient of the lateral wear depth of the blade on the gap is 1.1. The initial shear force in the strip shearing process is 34289N, the shear force after the first gap adjustment (adjusted to 0.55mm) is 34213N, and the shear force difference is 76N.

[0107] C3) It is judged that 76 is less than 161.9 at this time, that is, the change in shear force after the disc shear gap is adjusted is less than the additional shear force, then the original setting gap of the disc shear is adjusted to ψ=0.05, the shear force after the second gap adjustment is 34130N, and the shear force difference is 159N; it is judged that 159 is less than 161.9 at this time, that is, the change in shear force after the disc shear gap is adjusted is less than the additional shear force, then the original setting gap of the disc shear is adjusted to ψ=0.045, the shear force after the third gap adjustment is 34130N, and the shear force difference is 159N; it is judged that 159 is less than 161.9 at this time, that is, the change in shear force after the disc shear gap is adjusted is less than the additional shear force 34043; the change in shear force is 245.5; it is judged that 245.5 is greater than 161.9 at this time, that is, the change in shear force after the disc shear gap is adjusted is greater than the additional shear force, the cycle is ended, and the strip shear gap is adjusted to ψ=0.045mm.

Claims

1. A method for optimizing the process parameters of a disc shear when a strip is deviated, characterized in that: The steps include: A) Confirm the strip deviation type and calculate the deviation amount in the corresponding deviation type; determine whether there will be a transverse speed component during the shearing process of the disc shear; B) Calculate the additional force generated when the strip deviates and the additional shear force of the disc shear; C) Adjust the clearance of the disc shear.

2. The method for optimizing the process parameters of a circular shear when strip steel deviates according to claim 1 is characterized in that: The types of deviation of the strip in step A) include local deviation and overall deviation.

3. The method for optimizing the process parameters of a circular shear when the strip is deviated according to claim 1 is characterized in that: Step A) comprises the following sub-steps: A1) When there is local deviation, compare whether the deviation amount under the action of the deviation correction roller is not less than the deviation amount of the strip. If the condition is met, the disc shear will shear normally; if the condition is not met, the difference between the two is defined as the deviation amount Δδ; A2) When the whole strip is deviated, the strip deviation angle Δθ (°) is calculated according to the following formula: Among them, L jy is the distance from the pinch roller to the disc shear; L jdy It is the distance between the center line of the strip, the center line of the pinch roller and the intersection of the axis of the circular shear.

4. The method for optimizing the process parameters of a circular shear when the strip is deviated according to claim 3 is characterized in that: In step A1), the following calculation formula is used: Among them, L jp is the deviation correction amount under the action of the deviation correction roller (mm); P j is the clamping force of the pinch roller (N); L j is the length of the pinch roller (mm); b jp is the strip deviation position (mm); t is the deviation time (s); ρ is the density of the strip (kg / mm 3 ); b is the strip width (mm); h is the strip thickness (mm); l dj is the length of the strip in the contact area between the strip and the pinch roller (mm); x is the coordinate of the strip deviation position.

5. The method for optimizing the process parameters of a circular shear when a strip is deviated according to claim 1 is characterized in that: Step B) comprises the following sub-steps: B1) Calculate the correcting force F generated by the correcting function of the pinch roller when local deviation occurs. jp (N), the calculation formula is as follows: Where: P j is the clamping force of the pinch roller (N); L j is the length of the pinch roller (mm); Δδ is the difference between the deviation amount under the action of the deviation correction roller and the deviation amount of the strip; x is the coordinate of the strip deviation position; B2) When calculating the overall deviation, the deviation force F generated by the velocity component PP (N); the calculation formula is as follows: Where ρ is the strip density (kg / mm 3 ); b is the strip width (mm); h is the strip thickness (mm); V-strip running speed (mm / s); Δθ is the strip deviation angle (°); l dy is the contact length of the disc shear zone (mm); B3) Obtain the friction coefficient μ between the strip and the cutter disc, and calculate the additional shear force ΔP between the strip and the disc shear caused by the correction force generated by the correction roller. jp (N); Additional shear force ΔP between the strip and the disc shear generated by the running speed of the strip pp (N); and the additional shear force ΔP between the strip and the disc shear generated by the combined effect of the two conditions fj (N); the calculation formula is as follows:

6. The method for optimizing the process parameters of a circular shear when a strip is deviated according to claim 1 is characterized in that: Step C) comprises the following sub-steps: C1) Obtain the disc shear gap adjustment accuracy d (mm), set the disc shear accuracy adjustment step k, then the disc shear gap adjustment amount Δψ=kd; C2) Obtain the initial gap ψ0 of the disc shear during the shearing process, the wear depth influence coefficient λ; the total lateral wear depth w of the blade during the i-th shearing i (mm); Maximum wear depth w during the blade's service life max (mm); wear degree influence index c; ultimate strength of strip steel σ b (MPa); δ elongation of the strip; thickness of the strip h (mm); inclination angle a of the blade qx (°); The influence coefficient η of the blade lateral wear depth on the gap amount, calculate the initial shear force P0 during the strip shearing process, the shear force P after the i-th gap adjustment i , and the shear force difference ΔP; The calculation formula is as follows: C3) Determine whether the change in shear force after the disc shear gap is adjusted is greater than the additional shear force. If the condition is met, adjust the original set gap ψ0 of the disc shear to ψ=ψ0-Δψ. If not, set Δψ=Δψ+kd and return to step C2 until the condition is met.

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