A method for determining a cutting speed of a double-cut shear

Abstract

This invention discloses a method for determining the cutting speed of a multiple-length shear, belonging to the field of iron and steel smelting technology. During multiple-length shearing, the V... x =V 成 +(1.2±0.5)m / s, where V x Let V be the horizontal component of the linear velocity V along the X direction of the double-length shear line. 成 V is the linear velocity of the rolling mill rolls in the finished product rolling mill. In this invention, V is calculated using a formula. x However, because the shearing of the finished product by the multiple-length shears results in a speed drop, there is a minimum speed point, at which the speed value is V. xmin To ensure the finished product head does not bend, the shearing speed V must be maintained at m / s. xmin Greater than the linear speed V of the finished mill rolls 成 However, V xmin The state changes due to shearing, therefore V needs to be adjusted. x To ensure smooth cutting of finished products, a certain speed compensation is required. After on-site adjustments, the linear speed V of the multiple-length shears was adjusted. x Adjusted to V 成 When the velocity is +(1.2±0.5) m / s, the finished product has a better cooling effect on the cooling bed.

Description

Technical Field

[0001] This invention relates to the field of iron and steel smelting technology, and more specifically, to a method and apparatus for determining the speed of multiple-length shearing. Background Technology

[0002] Currently, the shearing speed of the multiple-length shear is adjusted according to the condition of the finished product on the cooling bed. When the head of the finished product on the cooling bed is bent, it indicates that the multiple-length shearing speed is insufficient and needs to be increased. When the head is bent, there will be certain resistance during the movement of the head on the skirt roller conveyor. When the resistance is too large, the head of the finished product will be thrown outward, causing the skirt plate to become messy and delaying the production rhythm. When the tail of the finished product on the cooling bed is bent, it indicates that the multiple-length shearing speed is too high and needs to be reduced. A bent tail will cause the steel to become messy on the cooling bed surface during the alignment process of the alignment roller conveyor, and the top alignment guard plate will produce non-length. The bent part at the tail needs to increase the shearing length at the fixed-length shearing point, resulting in a series of problems such as reduced yield.

[0003] Given the aforementioned problems, it is necessary to provide a method for determining the cutting speed of multiple-length wires. Summary of the Invention

[0004] The purpose of this invention is to overcome the shortcomings of the prior art and provide a method for determining the speed of shearing multiple-length wire.

[0005] The technical problem solved by this invention is achieved by the following technical solution.

[0006] This invention provides a method for determining the cutting speed of a double-length shear, wherein during double-length shear cutting, the V... x =V 成 +(1.2±0.5)m / s. Where, V x Let V be the horizontal component of the linear velocity V along the X direction of the double-length shear line. 成 This refers to the linear speed of the finished product rolling mill rolls.

[0007] The present invention has the following beneficial effects:

[0008] This invention provides a method for determining the cutting speed of a double-length shear, wherein during double-length shear cutting, the V... x =V 成 +(1.2±0.5)m / s. Because V x Less than V 成 At +0.7m / s, there is a possibility of head bending, which could cause steel irregularities on the cooling bed. x Greater than V 成 Excessive shearing can cause tail bending, leading to increased energy waste and reduced yield, but it will not cause steel irregularities on the cooling bed. This problem can be solved by adjusting the shear lead rate λ using the technical means of this invention. Wherein, V x Let V be the horizontal component of the linear velocity V along the X direction of the double-length shear line. xminThis is the lowest horizontal component of the linear velocity V along the X direction when the double-length shear is cutting the finished product. Because there is a velocity drop when the double-length shear is cutting the finished product, there is a minimum velocity point, at which the velocity value is V. xmin To ensure the finished product head does not bend, the shearing speed V must be maintained at m / s. xmin Greater than the minimum speed V 成 Control V x =V 成 +(1.2±0.5)m / s, so that the finished product can meet the production requirements on the cooling bed. Attached Figure Description

[0009] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of the present invention and should not be regarded as a limitation on the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0010] Figure 1 This is a schematic diagram showing the parameters corresponding to the shearing of a 25-size finished product;

[0011] Figure 2 This is a schematic diagram showing the parameters corresponding to the shearing of a 25-size finished product. Detailed Implementation

[0012] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below. Where specific conditions are not specified in the embodiments, conventional conditions or conditions recommended by the manufacturer shall apply. Reagents or instruments whose manufacturers are not specified are all conventional products that can be purchased commercially.

[0013] The following is a detailed description of a method for determining the cutting speed of multiple-length wires provided by an embodiment of the present invention.

[0014] This invention provides a method for determining the cutting speed of a multiple-length shear, wherein during multiple-length shear cutting, V is controlled. x =V 成 +(1.2±0.5)m / s. Where, V x Let V be the horizontal component of the linear velocity V along the X direction of the double-length shear line. 成 This refers to the linear speed of the finished product rolling mill rolls.

[0015] This invention provides a method for determining the cutting speed of a multiple-length shear, wherein during multiple-length shear cutting, V is controlled. x =V 成 +(1.2±0.5)m / s. Where, V x Let V be the horizontal component of the linear velocity V along the X direction of the double-length shear line.成 The linear speed of the rolling mill rolls is given by the length shear. When shearing finished products, the length is determined based on the linear speed V of the rolling mill. 成 It is necessary to set an appropriate cutting speed V for multiple-length shears. Because there is a speed drop when cutting the finished product with multiple-length shears, there will be a minimum speed point, at which the speed value is V. xmin m / s, to ensure that the finished product head does not bend, the horizontal component V along the X direction of the multiple-length shearing speed V must be guaranteed. x Greater than the minimum speed V 成 After on-site debugging, the speed V of the double-length shearing line was increased. x Adjusted to V 成 +(1.2±0.5)m / s, that is, in the actual production process, the V value is recorded for each cutting operation by the multiple-length shear. xmin (This value is the minimum linear speed of the shear machine calculated by converting the rotational speed after the speed drop recorded by the encoder during each shearing operation.) Based on experience, in V... 成 Based on this, a velocity compensation of (1.2±0.5) m / s is added, resulting in V. x This is the optimal linear speed for cutting finished products with a double-length shear. At this speed, the finished product meets national standards for cooling on the cooling bed, reducing head breakage.

[0016] Based on field experimental observations, different V x With V 成 Based on the experimental data, V was obtained. x =V 成 When the curvature of the finished product on the cooling bed is within the national standard range, the curvature is within the range of +(1.2±0.5)m / s.

[0017] In an optional implementation, Where B is the actual speed of the motor in revolutions per minute, D is the diameter of the shears in meters, and A is the angle between the horizontal component of the linear velocity V of the multiple-length shears along the X direction and the tangential direction of the linear velocity of the shear blade.

[0018] See Figure 1 and Figure 2 Taking the cutting of a 25mm specification finished product on a No. 4 shearing machine (shearing machine diameter is 1.04m) as an example, Where B is the actual rotational speed (rpm) of the No. 4 shear motor, D is the diameter of the shear (distance from the rotation center of the shear to the blade = 1.04m), the reduction ratio is 1.36, and A is the angle between the horizontal component of the linear velocity V of the double-length shear along the X direction and the tangential direction of the linear velocity of the blade = the angle between the blade and the original position when it contacts the finished product.

[0019] In an optional implementation, the change in the shearing speed of the double-length shear line is controlled by controlling the shear lead rate λ, where the shear lead rate λ = V / V 成 Where V is the linear velocity of the multiple-scale shearing, V 成 This refers to the linear speed of the finished product rolling mill.

[0020] In an optional implementation, a temperature check is added before the double-length shearing. When the detected temperature is 900±25℃, the shear lead rate λ remains constant. For every 50℃ decrease in temperature, the shear lead rate λ = λ0 + 0.02, where λ0 is the shear lead rate based on the steel specifications and the linear speed V of the finished mill rolls. 成 Preset experience values.

[0021] The shearing rate reduction is affected by the finished product temperature and the shear cross-sectional area. The lower the temperature, the greater the strength of the finished product, the greater the resistance to shearing, and the greater the shearing rate reduction. To ensure the shearing speed V of the shear blade after reduction... x Greater than the finished product speed V 成 Before the double-length shearing, a temperature detection is added. When the detection temperature is 900±25℃, the shear lead rate λ remains unchanged. For every 50℃ decrease in temperature, the shear lead rate λ=λ0+0.02. This ensures that under the condition of sudden temperature change, the shearing speed is too low, which will cause the head to bend and lead to the steel being disordered on the cooling bed.

[0022] In an optional implementation, when V xmin Less than the finished product linear speed V 成 At +0.7 m / s, the control rate for double-length shearing is λ = λ0 + [(V 成 +0.7)-V xmin ] / V 成 To prevent the finished product head from bending, where λ0 is determined based on the steel specifications and the linear speed V of the mill rolls. 成 Preset experience values.

[0023] In an optional implementation, when V xmin Greater than the finished product linear speed V 成 At +1.7 m / s, the control rate for double-length shearing is λ = λ0 - [V xmin -(V 成 +1.7)] / V 成 To prevent bending at the tail of the finished product, where λ0 is determined based on the steel specifications and the linear speed V of the mill rolls. 成 Preset experience values.

[0024] In an optional implementation, during actual production, V is controlled to be greater than V. x >V min >V 成 This is to ensure that the double-length shears can be used to cut the finished product smoothly.

[0025] In an optional implementation, the cosA value is related to the specification size. The cosA values ​​corresponding to the shearing machine of this invention are: 16 specification cosA = 0.923; 18 specification cosA = 0.913; 20 specification cosA = 0.908; 22 specification cosA = 0.894; 25 specification cosA = 0.880.

[0026] The features and performance of the present invention will be further described in detail below with reference to embodiments.

[0027] Example 1

[0028] The finished product of specification 25 was sheared on a shearing machine with a diameter of 1.04 meters, and the measured temperature was 910℃. The linear velocity of the finished product was V. 成 =10.8 m / s, with a preset lead rate λ0 of 1.27. The horizontal component of the linear velocity V along the X direction of the multiple-scale shear is calculated. Record V during double-length shearing. xmin =11.12m / s, at this time V xmin Less than the finished product linear speed V 成 +0.7m / s, the head of the cooling bed on the finished product did not show any bending. Adjusting this as the lower limit can ensure that the lower limit of the lead rate and the head bending still maintain a certain safety range. Lead rate of multiple-length shearing λ=λ0+[(V 成 +0.7)-V xmin ] / V 成 =1.27+(10.8+0.7-11.12) / 10.8≈1.27+0.035=1.31, according to λ=V / V 成 The calculated value is V = 10.8 * 1.31 = 14.148, indicating that the finished product will perform better on a cooling bed.

[0029] Example 2

[0030] The finished product of specification 25 was sheared on a shearing machine with a diameter of 1.04 meters. The measured temperature was 895℃, and the linear velocity of the finished product was V. 成 =10.0 m / s, with a preset lead rate λ0 of 1.2. The horizontal component of the linear velocity V along the X direction of the multiple-scale shear is calculated. Record V for each cut with a double-meter shear. xmin = 9.7 m / s, at this time V xmin Less than the finished product linear speed V 成 +0.7m / s, the head bends, and the lead rate of the double-scale shearing is λ=λ0+[(V 成 +0.7)-V xmin ] / V 成 =1.2 + (10.0 + 0.7 - 9.7) / 10 = 1.2 + 0.1, the finished product lead time rate λ is 1.3, according to λ = V / V 成 The calculated value is V = 10.0 * 1.3 = 13.0, indicating that the finished product will perform better on a cooling bed.

[0031] Example 3

[0032] A 20-gauge finished product was sheared on a 1.04-meter diameter shear machine. The measured temperature was 895℃, and the linear velocity of the finished product was V. 成=12.2 m / s, with a preset lead rate λ0 of 1.15. The horizontal component of the linear velocity V along the X direction of the multiple-scale shear line was calculated. Record V for each cut with a double-meter shear. xmin =11.9m / s, at this time V xmin Less than the finished product linear speed V 成 +0.7m / s, the head bends, and the lead rate of the double-scale shearing is λ=λ0+[(V 成 +0.7)-V xmin ] / V 成 =1.15 + (12.2 + 0.7 - 11.9) / 12.2 ≈ 1.15 + 0.08, the finished product lead time rate λ is 1.23, according to λ = V / V 成 The calculated value is V = 12.2 * 1.23 = 15.0, indicating that the finished product will perform better on a cooling bed.

[0033] Example 4

[0034] The finished product of specification 25 was sheared on a shearing machine with a diameter of 1.04 meters, and the measured temperature was 879℃. The linear velocity of the finished product was V. 成 =11.1 m / s, with a preset lead ratio λ0 of 1.35. The horizontal component of the linear velocity V along the X direction of the multiple-scale shear is calculated. Record V for each cut with a double-meter shear. xmin =12.9m / s, at this time V xmin Greater than the finished product linear speed V 成 +1.7 m / s, the tail bends, and the lead rate of the double-scale shear is λ = λ0 - [V xmin -(V 成 +1.7)] / V 成 =1.35 - 0.01. The finished product lead time rate λ is 1.34, according to λ = V / V 成 The calculated value is V = 11.1 * 1.34 = 14.874, indicating that the finished product will perform better on a cooling bed.

[0035] Example 5

[0036] Similar to the steps in Example 1, the 25-size finished product is sheared on a shearing machine with a diameter of 1.04 meters. The linear velocity V of the finished product is... 成 =10.8 m / s, with a preset lead ratio λ0 of 1.25. The horizontal component of the linear velocity V along the X direction of the multiple-scale shear is calculated. As the temperature decreases, the strength of the rolled piece increases, but the shearing speed does not increase, resulting in an increased rate drop. The V value is recorded during each shearing operation at multiple-length shearing intervals. xmin =10.7 m / s, the head bends. The lead rate of the double-length shearing λ = λ0 + (950 - 850) / 50 * 0.02 = 1.25 + 0.04. The finished product lead rate λ is 1.29, according to λ = V / V 成The calculated value is V = 11.1 * 1.34 = 13.932, indicating that the finished product will perform better on a cooling bed.

[0037] In summary, this invention provides a method for determining the cutting speed of a multiple-length shear, wherein during multiple-length shearing, the speed of V is controlled. x =V 成 +(1.2±0.5)m / s. Because V x Less than V 成 At +0.7m / s, there is a possibility of head bending, which could cause steel irregularities on the cooling bed. x Greater than V 成 Excessive shearing can cause tail bending, leading to increased energy waste and reduced yield, but it will not cause steel slag breakage accidents on the cooling bed. This problem can be solved by adjusting the shear lead rate λ using the technical means provided by this invention. Wherein, V x Let V be the horizontal component of the linear velocity V along the X direction of the double-length shear line. xmin This is the lowest horizontal component of the linear velocity V along the X direction when the double-length shear is cutting the finished product. Because there is a velocity drop when the double-length shear is cutting the finished product, there is a minimum velocity point, at which the velocity value is V. xmin To ensure the finished product head does not bend, the shearing speed V must be maintained at m / s. xmin Greater than the minimum speed V 成 After on-site debugging, the advance rate λ of the double-length shear was increased, and the finished product was placed on the cooling bed to meet production requirements.

[0038] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A method for determining the cutting speed of a double-length wire cutter, characterized in that, When cutting with a double-length shear, control V x =V 成 +(1.2±0.5)m / s, where, V x Let V be the horizontal component of the linear velocity V along the X direction of the double-length shear line. 成 The linear speed of the finished mill rolls; The change in the shear lead rate λ is controlled by controlling the shear lead rate λ, where λ = V / V 成 Where V is the linear velocity of the multiple-scale shearing, V 成 The linear speed of the finished product rolling mill; Before the double-length shearing, a temperature check is added. When the detected temperature is 900±25℃, the shear lead rate λ remains constant. For every 50℃ decrease in temperature, the shear lead rate λ = λ0 + 0.02, where λ0 is the shear lead rate based on the steel specifications and the linear speed V of the finished mill rolls. 成 Preset experience values; When V xmin Less than the finished product linear speed V 成 At +0.7 m / s, the control rate for double-length shearing is λ = λ0 + [(V 成 +0.7)-V xmin ] / V 成 To prevent the finished product head from bending, where λ0 is determined based on the steel specifications and the linear speed V of the mill rolls. 成 Preset experience values; When V xmin Greater than the finished product linear speed V 成 At +1.7 m / s, the control rate for double-length shearing is λ = λ0 - [V xmin -(V 成 +1.7)] / V 成 To prevent bending at the tail of the finished product, where λ0 is determined based on the steel specifications and the linear speed V of the mill rolls. 成 Preset experience values; In actual production, control V>V x >V xmin >V 成 This is to ensure that the double-length shears can be used to cut the finished product smoothly.

2. The method for determining the speed of double-length shearing as described in claim 1, characterized in that, Where B is the actual speed of the motor in revolutions per minute, D is the diameter of the shears in meters, and A is the angle between the horizontal component of the linear velocity V of the multiple-length shears along the X direction and the tangential direction of the linear velocity of the shear blade.

3. The method for determining the speed of double-length shearing as described in claim 1, characterized in that, The correspondence between steel specifications, shear diameter, and cosA value of the upper shear is as follows: steel specification 18, cosA=0.913; steel specification 20, cosA=0.908; steel specification 22, cosA=0.894; steel specification 25, cosA=0.880.

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