Control method and device for cutting crescent on strip steel

Abstract

The invention provides a control method and device for cutting a crescent on strip steel. The method comprises the following steps: determining a crescent cut-out position according to the width of a previous coil of strip steel, the width of a next coil of strip steel, the allowable minimum trimming amount of single-side trimming, the maximum depth of a shear blade, a trimming identifier of the previous coil of strip steel and a trimming identifier of the next coil of strip steel of a current welding seam; determining a strip steel speed control mode based on the crescent cutting position, the width of the previous strip steel coil and the width of the next strip steel coil; on the basis of the crescent cutting position and the strip steel speed control mode, a crescent shear is controlled to conduct crescent cutting operation on the strip steel; thus, according to the width change of the rolled material, the appropriate crescent shearing position is correspondingly determined, so that the requirement for accurate adjustment of the trimming width is met, unit tension and rolling force are prevented from being instantly increased, and therefore belt breakage accidents are reduced; and meanwhile, the proper crescent shearing position can improve the strip shape of the strip head, the phenomenon that the strip steel is broken after strip threading can be avoided, and the rolling quality of the strip steel is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of thin-gauge tandem cold rolling of acid rolling, and particularly relates to a control method and device for cutting a crescent shape on a strip steel. Background Art

[0002] A thin-gauge tandem cold rolling mill for acid rolling generally includes 5 sets of stands. The 5# stand is for bright roll rolling, with a set speed relatively high, and the maximum speed is usually above 1600 m / min. The thinnest material rolled can reach 0.12 mm, and the reduction ratio is usually above 90%.

[0003] Due to the frequent change of rolling specifications in the tandem cold rolling mill, especially the change in width, such as rolling from narrow to wide or from wide to narrow. To eliminate stress concentration, a crescent shear located at the welder position needs to cut a crescent shape at the strip steel weld. Further, to eliminate the breakage of the strip steel caused by edge defects (such as edge crack defects) in the hot-rolled incoming material, or to prevent the edge defects from affecting the stable operation of the subsequent production line, it is also necessary to trim the edges of both sides of the strip steel. At this time, a crescent shear located at the edge trimming shear position needs to cut a crescent shape in the strip steel weld area, so as to facilitate the edge trimming shear to adjust the shear width in time to trim the strip steel.

[0004] However, in actual applications, if the position of the cut crescent shape is inappropriate, it will cause a strip breakage accident; it will also lead to difficulties in adjusting the trimming width, with a large waviness after rolling and difficulties in threading, resulting in a strip breakage accident, thereby affecting the quality of the strip steel. Summary of the Invention

[0005] In view of the problems existing in the prior art, an embodiment of the present invention provides a control method and device for cutting a crescent shape on a strip steel, so as to solve or partially solve the technical problem that in the prior art, after cutting a crescent shape on the strip steel, it is easy to cause strip breakage or strip breakage accidents, thereby affecting the quality of the strip steel.

[0006] In a first aspect of the present invention, a control method for cutting a crescent shape on a strip steel is provided, and the method includes:

[0007] Determine the crescent cutting position according to the width of the previous coil of strip steel, the width of the next coil of strip steel, the minimum trimming amount allowed for unilateral trimming, the maximum depth of the shear blade, the trimming mark of the previous coil of strip steel, and the trimming mark of the next coil of strip steel;

[0008] Determine the strip steel speed control mode based on the crescent cutting position, the width of the previous coil of strip steel, and the width of the next coil of strip steel;

[0009] Control the crescent shear to perform a crescent cutting operation on the strip steel based on the crescent cutting position and the strip steel speed control mode.

[0010] In the above solution, determining the crescent cutting position according to the width of the previous coil strip, the width of the next coil strip, the minimum trimming amount allowed for single-side trimming, the maximum depth of the shearing blade, the trimming mark of the previous coil strip, and the trimming mark of the next coil strip of the current weld seam includes:

[0011] Determine the strip width difference and the strip width change mark according to the width of the previous coil strip and the width of the next coil strip of the current weld seam, and determine the strip depth difference according to the minimum trimming amount allowed for single-side trimming and the maximum depth of the shearing blade;

[0012] If it is determined that the strip width difference is less than or equal to the strip depth difference, the strip width change mark is the first mark, and the trimming marks of both the previous coil strip and the next coil strip are trimmed, then determine that the crescent cutting position is before the strip weld seam; the first mark is that the width changes from narrow to wide and the trimming parameters need to be adjusted;

[0013] If it is determined that the strip width difference is less than or equal to the strip depth difference, the strip width change mark is the same width, and the trimming marks of both the previous coil strip and the next coil strip are trimmed, then determine that the crescent cutting operation does not need to be performed;

[0014] If it is determined that the strip width difference is less than or equal to the strip depth difference, the strip width change mark is the second mark, and the trimming marks of both the previous coil strip and the next coil strip are trimmed, then determine that the crescent cutting position is before the strip weld seam; the second mark is that the width changes from wide to narrow and the trimming parameters need to be adjusted;

[0015] If it is determined that the strip width difference is less than or equal to the strip depth difference, the strip width change mark is the first target change mark, the trimming mark of the previous coil strip is trimmed, and the trimming mark of the next coil strip is not trimmed, then determine that the crescent cutting position is before the strip weld seam; the first target change mark is the first mark or the second mark or the third mark; the third mark is the same width and the trimming parameters do not need to be adjusted.

[0016] In the above solution, determining the crescent cutting position according to the width of the previous coil strip, the width of the next coil strip, the minimum trimming amount allowed for single-side trimming, the maximum depth of the shearing blade, the trimming mark of the previous coil strip, and the trimming mark of the next coil strip of the current weld seam includes:

[0017] Determine the strip width difference and the strip width change mark according to the width of the previous coil strip and the width of the next coil strip of the current weld seam, and determine the strip depth difference according to the minimum trimming amount allowed for single-side trimming and the maximum depth of the shearing blade;

[0018] If it is determined that the strip width difference is less than or equal to the strip depth difference, the strip width change identifier is the second target change identifier, the trimming identifier of the previous coil of strip is non-trimmed, and the trimming identifier of the next coil of strip is trimmed, then it is determined that the crescent cutting position is before the strip weld; the second target change identifier is the first identifier or the third identifier;

[0019] If it is determined that the strip width difference is less than or equal to the strip depth difference, the strip width change identifier is the second identifier, the trimming identifier of the previous coil of strip is non-trimmed, and the trimming identifier of the next coil of strip is trimmed, then it is determined that the crescent cutting position is after the strip weld;

[0020] If it is determined that the strip width difference is less than or equal to the strip depth difference, and the trimming identifiers of both the previous coil of strip and the next coil of strip are non-trimmed, then it is determined that the crescent cutting operation does not need to be performed.

[0021] In the above solution, determining the crescent cutting position according to the width of the previous coil of strip, the width of the next coil of strip, the minimum allowable trimming amount for single-sided trimming, the maximum depth of the shearing blade, the trimming identifier of the previous coil of strip, and the trimming identifier of the next coil of strip includes:

[0022] Determine the strip width difference and the strip width change identifier according to the width of the previous coil of strip and the width of the next coil of strip at the current weld, and determine the strip depth difference according to the minimum allowable trimming amount for single-sided trimming and the maximum depth of the shearing blade;

[0023] If it is determined that the strip width difference is greater than the strip depth difference and less than or equal to the preset threshold, the strip width change identifier is the first identifier, and the trimming identifiers of both the previous coil of strip and the next coil of strip are trimmed, then it is determined that the crescent cutting position is before the strip weld;

[0024] If it is determined that the strip width difference is greater than the strip depth difference and less than or equal to the preset threshold, the strip width change identifier is the second identifier, and the trimming identifiers of both the previous coil of strip and the next coil of strip are trimmed, then it is determined that the crescent cutting position is after the strip weld;

[0025] If it is determined that the strip width difference is greater than the strip depth difference and less than or equal to the preset threshold, the strip width change identifier is the third target identifier, the trimming identifier of the previous coil of strip is trimmed, and the trimming identifier of the next coil of strip is non-trimmed, then it is determined that the crescent cutting position is before the strip weld; the third target identifier is the first identifier or the second identifier.

[0026] In the above solution, the method further includes:

[0027] If it is determined that the strip width difference is greater than the strip depth difference and less than or equal to a preset threshold, the strip width change identifier is the first identifier, the trimming identifier of the previous strip is untrimmed, and the trimming identifier of the next strip is trimmed, then it is determined that the crescent cutting position is before the strip weld;

[0028] If it is determined that the strip width difference is greater than the strip depth difference and less than or equal to a preset threshold, the strip width change identifier is the second identifier, the trimming identifier of the previous strip is untrimmed, and the trimming identifier of the next strip is trimmed, then it is determined that the crescent cutting position is after the strip weld;

[0029] If it is determined that the strip width difference is greater than the strip depth difference and less than or equal to a preset threshold, the trimming identifier of the previous strip is untrimmed, and the trimming identifier of the next strip is untrimmed, then it is determined that the crescent cutting operation does not need to be performed.

[0030] In the above solution, the determining of the crescent cutting position according to the width of the previous strip, the width of the next strip, the minimum trimming amount allowed for single-sided trimming, the maximum depth of the shearing blade, the trimming identifier of the previous strip and the trimming identifier of the next strip of the current weld includes:

[0031] Determine the strip width difference and the strip width change identifier according to the width of the previous strip and the width of the next strip of the current weld, and determine the strip depth difference according to the minimum trimming amount allowed for single-sided trimming and the maximum depth of the shearing blade;

[0032] If it is determined that the strip width difference is greater than a preset threshold, the strip width change identifier is the first identifier, the trimming identifier of the previous strip is trimmed, and the trimming identifier of the next strip is trimmed, then it is determined that the crescent cutting position is before the strip weld;

[0033] If it is determined that the strip width difference is greater than a preset threshold, the strip width change identifier is the second identifier, the trimming identifier of the previous strip is trimmed, and the trimming identifier of the next strip is trimmed, then it is determined that the crescent cutting position is before the strip weld;

[0034] If it is determined that the strip width difference is greater than a preset threshold, the strip width change identifier is width getting narrower, the trimming identifier of the previous strip is trimmed, and the trimming identifier of the next strip is trimmed, then it is determined that the crescent cutting position is after the strip weld;

[0035] If it is determined that the width difference of the strip steel is greater than the preset threshold, the strip steel width change identifier is the fourth target identifier, the trimming identifier of the previous coil of strip steel is trimming, and the trimming identifier of the next coil of strip steel is non-trimming, then it is determined that there is no need to perform the crescent cutting operation; the fourth target identifier includes: the first identifier or the second identifier;

[0036] If it is determined that the width difference of the strip steel is greater than the preset threshold, the strip steel width change identifier is the first identifier, the trimming identifier of the previous coil of strip steel is non-trimming, and the trimming identifier of the next coil of strip steel is trimming, then it is determined that there is no need to perform the crescent cutting operation;

[0037] If it is determined that the width difference of the strip steel is greater than the preset threshold, the strip steel width change identifier is the second identifier, the trimming identifier of the previous coil of strip steel is non-trimming, and the trimming identifier of the next coil of strip steel is trimming, then it is determined that the crescent cutting position is after the strip steel weld.

[0038] In the above solution, if it is determined that the crescent cutting position is after the strip steel weld, the method further includes:

[0039] Determine the first distance between the roll gap of the last stand and the mandrel on the entrance side;

[0040] Determine the actual distance between the distal end of the crescent region and the weld according to the theoretical length of the crescent region and the theoretical distance between the distal end of the crescent region and the weld;

[0041] Determine the rolled length after deformation of the crescent region according to the finished thickness and raw material thickness of the strip steel;

[0042] Judge whether it is necessary to compensate the crescent cutting position according to the rolled length after deformation of the crescent region and the first distance. If necessary, determine the distance compensation value according to the distance between stands, the finished thickness and raw material thickness of the strip steel;

[0043] Determine the actual cutting position of the crescent region according to the theoretical distance between the distal end of the crescent region and the weld and the distance compensation value.

[0044] In the above solution, the determining the strip steel speed control mode based on the crescent cutting position, the width of the previous coil of strip steel and the width of the next coil of strip steel includes:

[0045] If it is determined that the width of the previous coil of strip steel is less than the width of the next coil of strip steel and the crescent cutting position is before the weld, then control the strip steel speed to decrease from the first running speed to the second running speed until the crescent cutting position of the previous coil of strip steel reaches the crescent shear, and then control the strip steel speed to decrease to zero;

[0046] If it is determined that the width of the previous coil of strip steel is greater than the width of the next coil of strip steel and the crescent cutting position is after the weld, then control the strip steel speed to decrease from the first running speed to the second running speed until the crescent cutting position of the next coil of strip steel reaches the crescent shear, and then control the strip steel speed to decrease to zero.

[0047] In the above solution, the determination of the strip steel speed control mode based on the crescent cutting position, the width of the previous coil of strip steel, and the width of the next coil of strip steel includes:

[0048] If it is determined that the width of the previous coil of strip steel is greater than the width of the next coil of strip steel and the trimming marks of both the previous coil of strip steel and the next coil of strip steel are non-trimming, then control the strip steel speed to pass through the crescent shear at the first running speed;

[0049] If it is determined that the width of the previous coil of strip steel is less than the width of the next coil of strip steel, the trimming mark of the previous coil of strip steel is non-trimming, and the trimming mark of the next coil of strip steel is trimming, then determine whether the weld cuts out a crescent at the welder position. If so, control the strip steel speed to pass through the crescent shear at the first running speed;

[0050] If it is determined that the width of the previous coil of strip steel is less than the width of the next coil of strip steel and the trimming marks of both the previous coil of strip steel and the next coil of strip steel are trimming, then determine whether the weld cuts out a crescent at the welder position. If so, control the strip steel speed to pass through the crescent shear at the first running speed.

[0051] In the second aspect of the present invention, there is provided a control device for cutting a crescent on strip steel, and the device includes:

[0052] A first determination unit, configured to determine the crescent cutting position according to the width of the previous coil of strip steel, the width of the next coil of strip steel, the minimum trimming amount allowed for single-side trimming, the maximum depth of the shear blade, the trimming mark of the previous coil of strip steel, and the trimming mark of the next coil of strip steel of the current weld;

[0053] A second determination unit, configured to determine the strip steel speed control mode based on the crescent cutting position, the width of the previous coil of strip steel, and the width of the next coil of strip steel;

[0054] A control unit, configured to control the crescent shear to perform a crescent cutting operation on the strip steel based on the crescent cutting position and the strip steel speed control mode.

[0055] The present invention provides a control method and device for cutting a crescent on a strip steel. The method includes: determining the crescent cutting position according to the width of the previous coil of strip steel, the width of the next coil of strip steel, the minimum trimming amount allowed for unilateral trimming, the maximum depth of the shearing blade, the trimming mark of the previous coil of strip steel, and the trimming mark of the next coil of strip steel; determining the strip steel speed control mode based on the crescent cutting position, the width of the previous coil of strip steel, and the width of the next coil of strip steel; controlling the crescent shear to perform the crescent cutting operation on the strip steel based on the crescent cutting position and the strip steel speed control mode; thus, according to the change in the width of the rolled material, an appropriate crescent shearing position is determined accordingly to meet the precise adjustment of the trimming width, avoid the instantaneous increase of the unit tension and rolling force, thereby reducing the occurrence of strip breakage accidents; at the same time, the appropriate crescent shearing position can improve the head shape of the strip steel and also avoid the phenomenon of strip breakage after threading, improving the rolling quality of the strip steel. BRIEF DESCRIPTION OF THE DRAWINGS

[0056] By reading the detailed description of the preferred embodiments below, various other advantages and benefits will become clear to those of ordinary skill in the art. The drawings are only for the purpose of showing the preferred embodiments and are not considered to be a limitation of the present invention. Moreover, throughout the drawings, the same reference numerals are used to represent the same components. In the drawings:

[0057] Figure 1 A schematic flow chart of the control method for cutting a crescent on a strip steel according to an embodiment of the present invention is shown;

[0058] Figure 2 A schematic diagram of the width difference between the previous coil of strip steel and the next coil of strip steel according to an embodiment of the present invention is shown;

[0059] Figure 3 A schematic diagram of the corresponding crescent cutting position when the width difference between the previous coil of strip steel and the next coil of strip steel is greater than a preset threshold, and both the previous coil of strip steel and the next coil of strip steel need to be trimmed and change from narrow to wide according to an embodiment of the present invention is shown;

[0060] Figure 4 A schematic diagram of the corresponding crescent area when the width difference between the previous coil of strip steel and the next coil of strip steel is greater than a preset threshold, and both the previous coil of strip steel and the next coil of strip steel need to be trimmed and change from narrow to wide according to an embodiment of the present invention is shown;

[0061] Figure 5 A schematic diagram of the corresponding crescent cutting position when the width difference between the previous coil of strip steel and the next coil of strip steel is greater than a preset threshold, and both the previous coil of strip steel and the next coil of strip steel need to be trimmed and change from wide to narrow according to an embodiment of the present invention is shown;

[0062] Figure 6 A schematic diagram of the corresponding crescent area when the width difference between the previous coil of strip steel and the next coil of strip steel is greater than a preset threshold, and both the previous coil of strip steel and the next coil of strip steel need to be trimmed and change from wide to narrow according to an embodiment of the present invention is shown;

[0063] Figure 7 Shows the schematic diagram of speed control when cutting a crescent before the weld seam and the width changes from narrow to wide according to an embodiment of the present invention;

[0064] Figure 8 Shows the schematic diagram of speed control when cutting a crescent before the weld seam and the width changes from wide to narrow according to an embodiment of the present invention;

[0065] Figure 9 Shows the schematic diagram of speed control when the width changes from narrow to wide and the previous coil and the next coil of strip steel do not need to be trimmed according to an embodiment of the present invention;

[0066] Figure 10 Shows the schematic diagram of speed control when the width changes from wide to narrow and the previous coil and the next coil of strip steel do not need to be trimmed according to an embodiment of the present invention;

[0067] Figure 11 Shows the schematic diagram of speed control when the width changes from narrow to wide, the previous coil of strip steel does not need to be trimmed, and the next coil of strip steel needs to be trimmed according to an embodiment of the present invention;

[0068] Figure 12 Shows the schematic diagram of speed control when the width changes from wide to narrow, the previous coil of strip steel needs to be trimmed, and the next coil of strip steel does not need to be trimmed according to an embodiment of the present invention;

[0069] Figure 13 Shows the schematic diagram of the structure of the control device for cutting a crescent on the strip steel according to an embodiment of the present invention. Detailed implementation manners

[0070] Hereinafter, exemplary embodiments of the present disclosure will be described in more detail with reference to the accompanying drawings. Although the exemplary embodiments of the present disclosure are shown in the drawings, it should be understood that the present disclosure can be implemented in various forms and should not be limited by the embodiments set forth herein. On the contrary, these embodiments are provided so that the present disclosure can be more thoroughly understood and the scope of the present disclosure can be completely conveyed to those skilled in the art.

[0071] For the thin-gauge acid rolling tandem mill, there are two positions where the strip steel can be cut into a crescent shape. One position is the crescent shear near the welder, and the other is the crescent shear next to the edge trimmer. If both crescent shears cut out a crescent shape at the strip steel weld seam, it will cause the strip steel width to become narrower. Then, after the crescent area enters the rolling mill, the unit tension and unit rolling force increase instantaneously, resulting in a strip break accident; if the position of the crescent cut by the crescent shear near the edge trimmer is inappropriate, it will also cause difficulties in adjusting the strip steel width or a large waviness in the crescent area after rolling, making it difficult to thread the strip after the flying shear cuts, and causing a break.

[0072] Based on this, an embodiment of the present invention provides a control method for cutting a crescent on a strip steel, as Figure 1 shown. The method mainly includes the following steps:

[0073] S110, determine the crescent cutting position according to the width of the previous coil of strip steel, the width of the next coil of strip steel, the minimum trimming amount allowed for unilateral trimming, the maximum depth of the shearing blade, the trimming mark of the previous coil of strip steel, and the trimming mark of the next coil of strip steel at the current weld.

[0074] In the actual rolling process, the parameters of the steel coils are different. For example, some steel coils need to be trimmed while some do not, some widths change while some do not.

[0075] Therefore, before rolling, the above parameters need to be set, mainly including the following aspects:

[0076] First, when trimming is required, the trimming mark is Y; when trimming is not required, the trimming mark is N; the previous coil at the weld is F, and the next coil at the weld is B;

[0077] Second, when the trimming parameters do not need to be adjusted and the width of the previous coil of strip steel and the next coil of strip steel changes from narrow to wide, the strip steel width change mark is marked as the fourth mark a;

[0078] When the trimming parameters need to be adjusted and the width of the previous coil of strip steel and the next coil of strip steel changes from narrow to wide, the strip steel width change mark is the first mark b;

[0079] When the trimming parameters do not need to be adjusted and the width of the previous coil of strip steel and the next coil of strip steel changes from wide to narrow, the strip steel width change mark is the fifth mark c;

[0080] When the trimming parameters need to be adjusted and the width of the previous coil of strip steel and the next coil of strip steel changes from wide to narrow, the strip steel width change mark is the second mark d;

[0081] When the trimming parameters do not need to be adjusted and the widths of the previous coil of strip steel and the next coil of strip steel are the same width, the strip steel width change mark is the third mark e;

[0082] When the trimming parameters need to be adjusted and the widths of the previous coil of strip steel and the next coil of strip steel are the same width, the strip steel width change mark is the sixth mark f.

[0083] Third, when the operation of cutting the crescent area is not required, the shearing mark M = 0; when the operation of cutting the crescent area is required before the weld, the shearing mark M = 1; when the operation of cutting the crescent area is required after the weld, the shearing mark M = 2.

[0084] To avoid the crescent region being too close to the weld region and affecting rolling, generally, the theoretical length R of the crescent region is 600 mm, and the theoretical distance L between the center position of the crescent region and the weld 0 is 700 mm.

[0085] During the actual rolling process, it is necessary to obtain the width of the previous coil of strip steel, the width of the next coil of strip steel, the minimum trimming amount X allowed for single-sided trimming 1 and the maximum depth X of the shearing blade 2 as well as the trimming marks of the previous coil of strip steel and the trimming marks of the next coil of strip steel, and then determine the crescent cutting position according to the width of the previous coil of strip steel, the width of the next coil of strip steel, the minimum trimming amount allowed for single-sided trimming, the maximum depth of the shearing blade, the trimming marks of the previous coil of strip steel and the trimming marks of the next coil of strip steel.

[0086] In the present invention, it is necessary to determine the strip width difference ΔX according to the width of the previous coil of strip steel and the width of the next coil of strip steel at the current weld, and then when ΔX ≤ X 2 -X 1 、X 2 -X 1 <ΔX ≤ X and ΔX > X, the implementation methods of the crescent cutting position are described separately in these three cases. X is a preset threshold, generally 99 mm. Among them, the strip width difference ΔX, the minimum trimming amount X allowed for single-sided trimming 1 and the maximum depth X of the shearing blade 2 can be as Figure 2 shown.

[0087] In one implementation, determining the crescent cutting position according to the width of the previous coil of strip steel, the width of the next coil of strip steel, the minimum trimming amount allowed for single-sided trimming, the maximum depth of the shearing blade, the trimming marks of the previous coil of strip steel and the trimming marks of the next coil of strip steel includes:

[0088] Determine the strip width difference and the strip width change mark according to the width of the previous coil of strip steel and the width of the next coil of strip steel at the current weld, and determine the strip depth difference according to the minimum trimming amount allowed for single-sided trimming and the maximum depth of the shearing blade;

[0089] If it is determined that the strip width difference is less than or equal to the strip depth difference, the strip width change mark is the first mark, and the trimming marks of both the previous coil of strip steel and the next coil of strip steel are trimming, then determine that the crescent cutting position is before the strip weld; the first mark is from narrow to wide and the trimming parameters need to be adjusted;

[0090] If it is determined that the strip width difference is less than or equal to the strip depth difference, the strip width change mark is the same width, and the trimming marks of both the previous coil of strip steel and the next coil of strip steel are trimming, then determine that there is no need to perform the crescent cutting operation;

[0091] If it is determined that the strip width difference is less than or equal to the strip depth difference, the strip width change identifier is the second identifier, and the trimming identifiers of the previous strip and the next strip are both trimmed, then it is determined that the crescent cutting position is before the strip weld; the second identifier is that the width becomes narrower and the trimming parameters need to be adjusted;

[0092] If it is determined that the strip width difference is less than or equal to the strip depth difference, the strip width change identifier is the first target change identifier, the trimming identifier of the previous strip is trimmed, and the trimming identifier of the next strip is not trimmed, then it is determined that the crescent cutting position is before the strip weld; the first target change identifier is the first identifier or the second identifier or the third identifier; the third identifier is that the width is the same and the trimming parameters do not need to be adjusted.

[0093] In one embodiment, the crescent cutting position is determined according to the width of the previous strip, the width of the next strip, the minimum allowable trimming amount for single-sided trimming, the maximum depth of the shearing blade, the trimming identifier of the previous strip and the trimming identifier of the next strip at the current weld, including:

[0094] Determine the strip width difference and the strip width change identifier according to the width of the previous strip and the width of the next strip at the current weld, and determine the strip depth difference according to the minimum allowable trimming amount for single-sided trimming and the maximum depth of the shearing blade;

[0095] If it is determined that the strip width difference is less than or equal to the strip depth difference, the strip width change identifier is the second target change identifier, the trimming identifier of the previous strip is not trimmed, and the trimming identifier of the next strip is trimmed, then it is determined that the crescent cutting position is before the strip weld; the second target change identifier is the first identifier or the third identifier;

[0096] If it is determined that the strip width difference is less than or equal to the strip depth difference, the strip width change identifier is the second identifier, the trimming identifier of the previous strip is not trimmed, and the trimming identifier of the next strip is trimmed, then it is determined that the crescent cutting position is after the strip weld;

[0097] If it is determined that the strip width difference is less than or equal to the strip depth difference, and the trimming identifiers of the previous strip and the next strip are both not trimmed, then it is determined that the crescent cutting operation does not need to be performed.

[0098] Specifically, there are two positions for the crescent cutting operation during the rolling process. One is to perform the crescent cutting operation at the welder position, and the other is to perform the crescent cutting operation at the crescent shear near the trimming shear; along the strip running direction, the strip first passes through the welder, and then passes through the crescent shear and the trimming shear in sequence. Unless otherwise specified, the crescent cutting operation mentioned in this article refers to the crescent cutting operation at the crescent shear.

[0099] In ΔX≤X 2 -X1 In the case where the trimming mark of the previous coil of strip is Y and the trimming mark of the next coil of strip is Y, it is divided into three cases:

[0100] (1) If the strip width change mark is the first mark b, it indicates that the width changes from narrow to wide. Since both the previous coil of strip and the next coil of strip need to be trimmed, the trimming parameters need to be adjusted. Then the crescent cutting position is before the strip weld.

[0101] (2) If the strip width change mark is the third mark e, it indicates that the width remains unchanged. Although both the previous coil of strip and the next coil of strip need to be trimmed, the width does not need to be adjusted. Then the operation of cutting out the crescent is not required.

[0102] (3) If the strip width change mark is the second mark d, it indicates that the width changes from wide to narrow. Since both the previous coil of strip and the next coil of strip need to be trimmed, the trimming parameters need to be adjusted. Then the crescent cutting position is before the strip weld.

[0103] In summary, when the difference between the width of the previous coil of strip and the width of the next coil of strip is not large and both require trimming, whether the width changes from narrow to wide or from wide to narrow, the crescent cutting operation is performed before the weld. This can reduce the edge wire treatment at the head of the next coil of strip and also avoid the poor strip shape in the crescent area at the head when making width adjustment by cutting the crescent at the head of the next coil of strip, which may cause difficulties in threading the strip through the rolling mill. And under this condition, since the width change of the previous coil of strip and the next coil of strip is relatively small, the welding machine does not cut out a crescent at the strip weld, preventing the occurrence of edge blocking and edge running during trimming.

[0104] When ΔX ≤ X 2 -X 1 In the case where the trimming mark of the previous coil of strip is Y and the trimming mark of the next coil of strip is N, it is divided into three cases:

[0105] (1) If the strip width change mark is the first mark b, it indicates that the width changes from narrow to wide. Since the previous coil of strip needs to be trimmed and the next coil of strip does not need to be trimmed, at this time, the trimming shear blade needs to perform an exit operation, and the trimming parameters need to be adjusted. Then the crescent cutting position is before the strip weld.

[0106] (2) If the strip width change mark is the third mark e, since the previous coil of strip needs to be trimmed and the next coil of strip does not need to be trimmed, at this time, the trimming shear blade needs to perform an exit operation, and the trimming parameters need to be adjusted. Then the crescent cutting position is before the strip weld.

[0107] (3) If the strip width change mark is the third mark d, since the previous coil of strip needs to be trimmed and the next coil of strip does not need to be trimmed, at this time, the trimming shear blade needs to perform an exit operation, and the trimming parameters need to be adjusted. Then the crescent cutting position is before the strip weld.

[0108] It should be noted that the crescent cutting position before the strip weld can be understood as a preset position before the weld (such as a position 700 mm away from the weld), and the crescent cutting position after the strip weld can be understood as a preset position after the weld (such as a position 700 mm away from the weld).

[0109] In the case of ΔX ≤ X 2 -X 1 When the trimming mark of the previous coil of strip is N and the trimming mark of the next coil of strip is Y, there are three cases:

[0110] (1) If the strip width change mark is the first mark b, since the previous coil of strip does not need to be trimmed and the next coil of strip needs to be trimmed, at this time, the trimming shear blade needs to perform a feeding operation, then the trimming parameters need to be adjusted, and the crescent cutting position is before the strip weld.

[0111] (2) If the strip width change mark is the third mark e, since the previous coil of strip does not need to be trimmed and the next coil of strip needs to be trimmed, at this time, the trimming shear blade needs to perform a feeding operation, then the trimming parameters need to be adjusted, and the crescent cutting position is before the strip weld.

[0112] (2) If the strip width change mark is the second mark d, since the previous coil of strip does not need to be trimmed and the next coil of strip needs to be trimmed, at this time, the trimming shear blade needs to perform a feeding operation, then the trimming parameters need to be adjusted, and the crescent cutting position is after the strip weld.

[0113] In the case of ΔX ≤ X 2 -X 1 When the trimming mark of the previous coil of strip is N and the trimming mark of the next coil of strip is N, it is determined that the previous coil of strip and the next coil of strip do not need to be trimmed, then the trimming parameters do not need to be adjusted, so the crescent cutting operation is not performed.

[0114] It should be noted that in the case of ΔX ≤ X 2 -X 1 it indicates that the width difference between the previous coil of strip and the next coil of strip is relatively small. To ensure the stability of trimming, when performing the crescent cutting operation before the weld and after the weld, the crescent shear on the welder side no longer performs the small crescent cutting operation to prevent cutting a large crescent before the weld, and then passing through the small crescent at the weld after the trimming shear feeds, resulting in a running edge and jamming accident.

[0115] In another embodiment, the crescent cutting position is determined according to the width of the previous coil of strip, the width of the next coil of strip, the minimum trimming amount allowed for unilateral trimming, the maximum depth of the shear blade, the trimming mark of the previous coil of strip, and the trimming mark of the next coil of strip, including:

[0116] Determine the strip width difference and the strip width change identifier based on the width of the previous strip and the width of the next strip of the current weld seam, and determine the strip depth difference based on the minimum trimming amount allowed for unilateral trimming and the maximum depth of the shearing blade;

[0117] If it is determined that the strip width difference is greater than the strip depth difference and less than or equal to a preset threshold, the strip width change identifier is the first identifier, and the trimming identifiers of both the previous strip and the next strip are trimming, then it is determined that the crescent cut-out position is before the strip weld seam;

[0118] If it is determined that the strip width difference is greater than the strip depth difference and less than or equal to a preset threshold, the strip width change identifier is the second identifier, and the trimming identifiers of both the previous strip and the next strip are trimming, then it is determined that the crescent cut-out position is after the strip weld seam;

[0119] If it is determined that the strip width difference is greater than the strip depth difference and less than or equal to a preset threshold, the strip width change identifier is the third target identifier, the trimming identifier of the previous strip is trimming, and the trimming identifier of the next strip is non-trimming, then it is determined that the crescent cut-out position is before the strip weld seam; the third target identifier is the first identifier or the second identifier.

[0120] Specifically, in the case of X 2 -X 1 <ΔX≤X, when the trimming identifier of the previous strip is Y and the trimming identifier of the next strip is Y, it is divided into two cases:

[0121] (1) If the strip width change identifier is the first identifier b, since the previous strip needs to be trimmed and the next strip needs to be trimmed, the trimming parameters need to be adjusted. Therefore, the crescent cut-out position is before the strip weld seam to facilitate the trimming shear to perform a retraction operation on the narrow strip and make a width adjustment.

[0122] (2) If the strip width change identifier is the third identifier d, since the previous strip needs to be trimmed and the next strip needs to be trimmed, the trimming parameters need to be adjusted. Therefore, the crescent cut-out position is after the strip weld seam.

[0123] In the case of X 2 -X 1 <ΔX≤X, when the trimming identifier of the previous strip is Y and the trimming identifier of the next strip is N, it is divided into two cases:

[0124] (1) If the strip width change identifier is the first identifier b, since the previous strip needs to be trimmed and the next strip does not need to be trimmed, the trimming parameters need to be adjusted, and the trimming shear needs to perform a retraction (the shearing blade retracts). Therefore, the crescent cut-out position is before the strip weld seam.

[0125] (2) If the strip width change is marked as the third mark d, since the previous strip needs to be trimmed and the next strip does not need to be trimmed, the trimming parameters need to be adjusted, and the trimming shears need to retract (the shear blades retract), so the crescent cutting position is before the strip weld.

[0126] At X 2 -X 1 When -X < ΔX ≤ X, if the trimming mark of the previous strip is N and the trimming mark of the next strip is Y, it is divided into two cases:

[0127] (1) If the strip width change is marked as the first mark b, since the previous strip does not need to be trimmed and the next strip needs to be trimmed, the trimming parameters need to be adjusted, and the trimming shears need to advance in advance, so the crescent cutting position is before the strip weld.

[0128] (2) If the strip width change is marked as the third mark d, since the previous strip does not need to be trimmed and the next strip needs to be trimmed, the trimming parameters need to be adjusted, and the trimming shears need to advance in advance, so the crescent cutting position is after the strip weld.

[0129] At X 2 -X 1 When -X < ΔX ≤ X, if the trimming mark of the previous strip is N and the trimming mark of the next strip is N, it is determined that the previous strip and the next strip do not need to be trimmed, so the trimming parameters do not need to be adjusted, and the crescent cutting operation is not performed.

[0130] In another embodiment, the crescent cutting position is determined according to the width of the previous strip, the width of the next strip, the minimum trimming amount allowed for one-sided trimming, the maximum depth of the shear blade, the trimming mark of the previous strip, and the trimming mark of the next strip at the current weld, including:

[0131] Determine the strip width difference and the strip width change mark according to the width of the previous strip and the width of the next strip at the current weld, and determine the strip depth difference according to the minimum trimming amount allowed for one-sided trimming and the maximum depth of the shear blade;

[0132] If it is determined that the strip width difference is greater than the preset threshold, the strip width change mark is the first mark, the trimming mark of the previous strip is trimming, and the trimming mark of the next strip is trimming, then it is determined that the crescent cutting position is before the strip weld;

[0133] If it is determined that the strip width difference is greater than the preset threshold, the strip width change mark is the second mark, the trimming mark of the previous strip is trimming, and the trimming mark of the next strip is trimming, then it is determined that the crescent cutting position is before the strip weld;

[0134] If it is determined that the strip width difference is greater than the preset threshold, the strip width change identifier is wide to narrow, the trimming identifier of the previous strip is trimmed, and the trimming identifier of the next strip is trimmed, then it is determined that the crescent cutting position is after the strip weld;

[0135] If it is determined that the strip width difference is greater than the preset threshold, the strip width change identifier is the fourth target identifier, the trimming identifier of the previous strip is trimmed, and the trimming identifier of the next strip is not trimmed, then it is determined that the crescent cutting operation does not need to be performed; the fourth target identifier includes: the first identifier or the second identifier;

[0136] If it is determined that the strip width difference is greater than the preset threshold, the strip width change identifier is the first identifier, the trimming identifier of the previous strip is not trimmed, and the trimming identifier of the next strip is trimmed, then it is determined that the crescent cutting operation does not need to be performed;

[0137] If it is determined that the strip width difference is greater than the preset threshold, the strip width change identifier is the second identifier, the trimming identifier of the previous strip is not trimmed, and the trimming identifier of the next strip is trimmed, then it is determined that the crescent cutting position is after the strip weld.

[0138] Specifically, in the case of ΔX > X, when the trimming identifier of the previous strip is Y and the trimming identifier of the next strip is Y, it is divided into two cases:

[0139] (1) If the strip width change identifier is the first identifier b (narrow to wide), since the previous strip needs to be trimmed and the next strip needs to be trimmed, the trimming parameters need to be adjusted, and the trimming shear needs to retract the tool in advance on the narrow strip for width adjustment (retract the tool at the crescent), so the crescent cutting position is before the strip weld.

[0140] Among them, the crescent cutting position A1 is as Figure 3 shown, the cut crescent area B1 and the trimming shear width adjustment position B1 are as Figure 4 shown.

[0141] (2) If the strip width change identifier is the second identifier d (wide to narrow), since the previous strip needs to be trimmed and the next strip needs to be trimmed, the trimming parameters need to be adjusted, so the crescent cutting position is after the strip weld.

[0142] Among them, the crescent cutting position A2 is as Figure 5 shown, the cut crescent area B2 is as Figure 6 shown.

[0143] In the case of ΔX > X, when the trimming identifier of the previous strip is Y and the trimming identifier of the next strip is N, it is divided into two cases:

[0144] (1) If the strip width change is marked as the first mark b (narrow to wide), the previous strip needs to be trimmed, and the next strip does not need to be trimmed. Since the width difference between the previous strip and the next strip is large, there is no need to cut out a crescent moon.

[0145] (2) If the strip width change is marked as the third mark d (wide to narrow), the previous strip needs to be trimmed, and the next strip does not need to be trimmed. Since the width difference between the previous strip and the next strip is large, there is no need to cut out a crescent moon.

[0146] In the case of ΔX > X, when the trimming mark of the previous strip is N and the trimming mark of the next strip is Y, it is divided into two cases:

[0147] (1) If the strip width change is marked as the first mark b (narrow to wide), the previous strip does not need to be trimmed, and the next strip needs to be trimmed. Since the width difference between the previous strip and the next strip is large, there is no need to cut out a crescent moon.

[0148] (2) If the strip width change is marked as the third mark d (wide to narrow), the previous strip does not need to be trimmed, and the next strip needs to be trimmed. It is necessary to cut out a crescent moon at the leading end of the narrow strip. Therefore, the crescent moon cutting position is after the strip weld.

[0149] In this way, the appropriate crescent moon cutting position is determined according to the different changes in strip width and their respective trimming requirements.

[0150] It should be noted that when it is determined that the crescent moon cutting position is after the strip weld, since the length of the crescent moon area is generally 600 mm and the distance between the center position of the crescent moon area and the weld is 700 mm, then in theory, the distance between the outermost end of the crescent moon area and the weld is 1000 mm.

[0151] However, when the reduction rate of the crescent moon area is 90%, after the length of the crescent moon area is extended, it will reach 10000 mm. This may cause the crescent moon area to be exactly at the roll gap of the last stand (5# stand) when the crescent moon area passes through the last stand, resulting in poor plate shape. In severe cases, a breakage accident may occur at the mill exit. Therefore, it is necessary to compensate the crescent moon cutting position according to the rolling thickness and reduction rate to ensure that the crescent moon area is far from the 5# stand roll gap, so that the crescent moon area is at the exit position of the 5# stand or the crescent moon area is located between the 4# stand and the 5# stand.

[0152] Based on this, in one implementation, if it is determined that the crescent moon cutting position is after the strip weld, the method further includes:

[0153] Determine the first distance between the roll gap of the last stand and the mandrel on the entry side;

[0154] Determine the actual distance between the distal end of the crescent region and the weld according to the theoretical length of the crescent region and the theoretical distance between the distal end of the crescent region and the weld;

[0155] Determine the rolled length after deformation of the crescent region according to the finished thickness and raw material thickness of the strip steel;

[0156] Judge whether it is necessary to compensate the crescent cutting position according to the rolled length after deformation of the crescent region and the first distance. If necessary, determine the distance compensation value according to the distance between stands, the finished thickness and raw material thickness of the strip steel;

[0157] Determine the actual cutting position of the crescent region according to the theoretical distance between the center of the crescent region and the weld and the distance compensation value.

[0158] Specifically, the distance S between the roll gap of the 5# stand and the mandrel on the entrance side 0 = 5.4 + 2.8 = 8.2 m; the raw material thickness of the strip steel is H, the finished thickness is h, and the actual distance L between the distal end (the farthest end) of the crescent region and the weld 1 is: R is the chord length of the crescent region, L 0 is the theoretical distance between the center of the crescent region and the weld, generally 700 mm;

[0159] The rolled length after deformation of the crescent region

[0160] If S < S 0 , then determine the distance compensation value L * = 0;

[0161] If S ≥ S 0 , then determine the distance compensation value S 2 is the distance between stands, and S 2 is 5.5 m.

[0162] At this time, the compensation distance L is: L = L * + L 0 .

[0163] That is, when it is determined to cut out the crescent position behind the weld, if it is determined that the crescent cutting position needs to be compensated, then determine the actual cutting position of the crescent region according to the compensation distance L.

[0164] S111, determine the strip steel speed control mode based on the crescent cutting position, the width of the previous coil of strip steel and the width of the next coil of strip steel.

[0165] After the crescent cutting position is determined, it is also necessary to determine the strip steel speed control mode according to the crescent cutting position, the width of the previous coil of strip steel and the width of the next coil of strip steel to ensure the cutting quality of the crescent region.

[0166] In one embodiment, a strip speed control mode is determined based on the crescent cutting position, the width of the previous coil of strip, and the width of the next coil of strip, including:

[0167] If it is determined that the width of the previous coil of strip is less than the width of the next coil of strip and the crescent cutting position is before the weld, the strip speed is controlled to decrease from the first operating speed to the second operating speed until the crescent cutting position of the previous coil of strip reaches the crescent shear, and then the strip speed is controlled to decrease to zero;

[0168] If it is determined that the width of the previous coil of strip is greater than the width of the next coil of strip and the crescent cutting position is after the weld, the strip speed is controlled to decrease from the first operating speed to the second operating speed until the crescent cutting position of the next coil of strip reaches the crescent shear, and then the strip speed is controlled to decrease to zero.

[0169] Specifically, if it is determined that the strip width changes from narrow to wide (the width of the previous coil of strip is less than the width of the next coil of strip), width adjustment is required, and the crescent cutting position is before the weld. As Figure 7 shown, it is necessary to select a position at a distance L 0 from the weld in the tail region of the previous coil of strip (narrow strip) for crescent cutting. The crescent cutting position is A3, and the crescent region is B3.

[0170] Therefore, it is necessary to control the strip speed to decrease from the first operating speed V1 to the second operating speed V2. When it is determined that the crescent cutting position (located at the tail of the previous coil of strip) reaches the crescent shear position, the strip running speed is controlled to decrease to 0 (stop). After determining that the crescent region is cut out, the strip running speed is controlled to increase from 0 to the first operating speed.

[0171] After running for a preset duration, the first operating speed V1 is controlled to decrease to the second operating speed V2 until the crescent region runs to the trimming shear position, and then the strip running speed is controlled to decrease to 0 (stop) again, facilitating the trimming shear to perform the feed operation and adjust the width of the next coil of strip. After the width adjustment is completed, the strip is first lifted to the second operating speed V2 and then to the first operating speed V1. Among them, the first operating speed is generally 60 m / s, and the second operating speed is generally 15 m / s.

[0172] Similarly, if it is determined that the strip width changes from wide to narrow (the width of the previous coil of strip is greater than the width of the next coil of strip), width adjustment is required, and the crescent cutting position is after the weld. As Figure 8 shown, it is necessary to select a position at a distance L 0 from the weld in the head region of the previous coil of strip (wide strip) for crescent cutting. The crescent cutting position is A4, and the crescent region is B4.

[0173] Therefore, it is necessary to control the strip speed to decrease from the first running speed V1 to the second running speed V2. When it is determined that the crescent cutting position (at the leading end of the next coil of strip) reaches the crescent shear position, control the strip running speed to decrease to 0 (stop). After determining that the crescent area has been cut out, control the strip running speed to increase from 0 to the first running speed.

[0174] After running for a preset duration, control the first running speed V1 to decrease to the second running speed V2 until the crescent area runs to the trimming shear position. Then, control the strip running speed to decrease to 0 (stop) again to facilitate the retraction operation of the trimming shear. Next, control the strip to first increase to the second running speed V2 and then increase to the first running speed V1.

[0175] In another embodiment, based on the crescent cutting position, the width of the previous coil of strip, and the width of the next coil of strip, determine the strip speed control mode, including:

[0176] If it is determined that the width of the previous coil of strip is greater than the width of the next coil of strip and the trimming marks of both the previous coil of strip and the next coil of strip are not to be trimmed, then control the strip speed to pass through the crescent shear at the first running speed;

[0177] If it is determined that the width of the previous coil of strip is less than the width of the next coil of strip, the trimming mark of the previous coil of strip is not to be trimmed, and the trimming mark of the next coil of strip is to be trimmed, then determine whether the weld cuts out a crescent at the welder position. If so, control the strip speed to pass through the crescent shear at the first running speed;

[0178] If it is determined that the width of the previous coil of strip is less than the width of the next coil of strip and the trimming marks of both the previous coil of strip and the next coil of strip are to be trimmed, then determine whether the weld cuts out a crescent at the welder position. If so, control the strip speed to pass through the crescent shear at the first running speed.

[0179] Specifically, if it is determined that the strip width changes from wide to narrow or from narrow to wide, and neither the previous coil of strip nor the next coil of strip needs to be trimmed and no width adjustment is made, as shown in Figure 9 and Figure 10 respectively, the strip can be controlled to always run at the first speed.

[0180] In addition, if it is determined that the strip width changes from narrow to wide, the previous coil of strip does not need to be trimmed, the next coil of strip needs to be trimmed, and the crescent cutting operation has been performed at the welder, satisfying the retraction operation of the trimming shear. As shown in Figure 11 respectively, the strip can be controlled to pass through the crescent shear at the first running speed V1. When it is determined that the strip weld has passed through the crescent shear for a preset duration, control the strip to decrease from the first running speed to the second running speed until it is determined that the preset position of the strip reaches the trimming shear position, and control the strip speed to 0 to leave a trimming shear allowance for width adjustment. The preset position of the strip can be the position C at the trailing end of the previous coil of strip, and the distance from position C to the strip weld is 115 mm.

[0181] If it is determined that the strip width changes from wide to narrow, the previous strip needs to be trimmed, and the next strip also needs to be trimmed. Moreover, the crescent cutting operation has been performed at the welder, satisfying the retraction operation of the trimming shear. As Figure 12 shown, the strip can be controlled to pass through the crescent shear at the first running speed V1. When it is determined that the strip weld has passed through the crescent shear for a preset duration, the strip is controlled to decelerate from the first running speed to the second running speed until it is determined that the preset position of the strip reaches the position of the trimming shear, and the strip speed is controlled to 0 to leave a margin for the trimming shear for width adjustment. The preset position of the strip can be the position D at the leading end of the next strip, and the position D is 115 mm away from the strip weld.

[0182] Among them, Figure 11 the +115 mm in Figure 12 and the -115 mm in

[0183] are mainly used to distinguish whether the crescent is cut before or after the weld. For example, +115 mm represents that the crescent is cut before the weld, and -115 mm represents that the crescent is cut after the weld.

[0184] After both the crescent cutting position and the strip speed control mode are determined, the crescent shear can be controlled to perform the crescent cutting operation on the strip according to the crescent cutting position and the strip speed control mode.

[0185] In this way, by corresponding to the width change of the rolled material, an appropriate crescent shear position can be determined to meet the precise adjustment of the trimming width, avoid the instantaneous increase of the unit tension and rolling force, thereby reducing the occurrence of strip breakage accidents; at the same time, the appropriate crescent shear position can improve the shape of the leading end of the strip and also avoid the phenomenon of strip breakage after threading, improving the rolling quality of the strip.

[0186] Based on the same inventive concept as in the foregoing embodiments, this embodiment further provides a control device for cutting a crescent on a strip, as Figure 13 shown. The device includes:

[0187] A first determination unit 131, configured to determine the crescent cutting position according to the width of the previous strip, the width of the next strip, the minimum trimming amount allowed for unilateral trimming, the maximum depth of the shear blade, the trimming mark of the previous strip, and the trimming mark of the next strip of the current weld;

[0188] A second determination unit 132, configured to determine the strip speed control mode based on the crescent cutting position, the width of the previous strip, and the width of the next strip;

[0189] A control unit 133 is configured to control the crescent shear to perform a crescent cutting operation on the strip steel based on the crescent cutting position and the strip steel speed control mode.

[0190] Since the device introduced in the embodiments of the present invention is the device adopted for implementing the control method for cutting a crescent on strip steel in the embodiments of the present invention, based on the method introduced in the embodiments of the present invention, those skilled in the art can understand the specific structure and variations of the device, so it will not be elaborated herein. Any device adopted by the method in the embodiments of the present invention falls within the scope of protection of the present invention.

[0191] In practical applications, when performing a crescent cutting operation on the strip steel of a certain steel mill using the control method and device for cutting a crescent on strip steel provided in the above embodiments, the following is implemented:

[0192] Embodiment 1

[0193] The thickness of the previous coil of strip steel is 0.203 mm, the width is 965 mm, and the raw material thickness is 2.0 mm; the thickness of the next coil of strip steel is 0.233 mm, the width is 953 mm, and the raw material thickness is 2.0 mm; both the previous coil of strip steel and the next coil of strip steel need to be trimmed. The maximum depth X of the trimming shear blade 2 is 25 mm, and the minimum trimming amount X allowed for single-sided trimming 1 is 5 mm, and no crescent cutting operation is performed at the welder.

[0194] Determine the strip steel width difference ΔX = 965 - 953 = 12 mm. Since ΔX ≤ X 2 -X 1 ; then if both the previous coil of strip steel and the next coil of strip steel need to be trimmed and change from wide to narrow, width adjustment is required. Therefore, it is determined that the crescent cutting position is before the weld. Therefore, a crescent cutting operation is performed at a position 700 mm away from the weld in the tail area of the previous coil of strip steel.

[0195] When performing speed control, control the strip steel speed to decrease from the first running speed V1 to the second running speed V2. When it is determined that the crescent cutting position (located at the head of the next coil of strip steel) reaches the crescent shear position, control the strip steel running speed to decrease to 0 (stop). After determining that the crescent area is cut out, control the strip steel running speed to increase from 0 to the first running speed.

[0196] After running for a preset duration, control the first running speed V1 to decrease to the second running speed V2 until the crescent area runs to the trimming shear position. Then, control the strip steel running speed to decrease to 0 (stop) again to facilitate the trimming shear to perform a retraction operation. Then, control the strip steel to first increase to the second running speed V2 and then increase to the first running speed V1.

[0197] Embodiment 2

[0198] The thickness of the previous coil of strip is 0.194 mm, the width is 894 mm, and the raw material thickness is 2.0 mm; the thickness of the next coil of strip is 0.173 mm, the width is 813 mm, and the raw material thickness is 2.0 mm; both the previous coil of strip and the next coil of strip need to be trimmed. The maximum depth X of the trimming shears 2 is 25 mm, and the minimum trimming amount X allowed for single-sided trimming 1 is 5 mm, and the crescent cutting operation is not performed at the welder.

[0199] Determine the strip width difference ΔX = 894 - 813 = 81 mm. Since ΔX > X 2 - X 1 , the widths of the previous coil of strip and the next coil of strip differ greatly, and width adjustment is required. Therefore, it is determined that the crescent cutting position is after the weld. Generally speaking, the crescent cutting operation needs to be performed at a position 700 mm away from the weld in the leading area of the next coil of strip.

[0200] However, since the crescent cutting operation is performed after the weld, compensation for the crescent cutting position is required.

[0201] First, obtain the chord length R = 600 mm of the crescent area, and the theoretical distance L between the center of the crescent area and the weld 0 = 700 mm;

[0202] The actual distance L between the far end (the farthest end) of the crescent area and the weld 1 is: = 1000 mm = 10 m;

[0203] The raw material thickness H of the next coil of strip is 2.0 mm, the finished product thickness h = 0.173 mm, and the distance S between the roll gap of the 5# stand and the mandrel on the entrance side 0 = 5.8 + 2.4 = 8.2 m, and the distance between stands S 2 = 5.5 m.

[0204] The rolled length after deformation of the crescent area

[0205] Since S ≥ S 0 , the distance compensation value is determined

[0206] At this time, the compensation distance L can be determined as: L = L * + L 0 = 1175 mm.

[0207] That is, the crescent cutting operation needs to be performed at a position 1175 mm away from the weld in the leading area of the next coil of strip to ensure that the crescent area is far from the roll gap of the 5# stand and ensure stable threading.

[0208] Through one or more embodiments of the present invention, the present invention has the following beneficial effects or advantages:

[0209] The present invention provides a control method and device for cutting a crescent moon on a strip steel. The method includes: determining the crescent moon cutting position according to the width of the previous coil of strip steel, the width of the next coil of strip steel, the minimum trimming amount allowed for unilateral trimming, the maximum depth of the shearing blade, the trimming mark of the previous coil of strip steel, and the trimming mark of the next coil of strip steel; determining the strip steel speed control mode based on the crescent moon cutting position, the width of the previous coil of strip steel, and the width of the next coil of strip steel; controlling the crescent moon shear to perform the crescent moon cutting operation on the strip steel based on the crescent moon cutting position and the strip steel speed control mode; thus, according to the change in the width of the rolled material, an appropriate crescent moon shearing position is correspondingly determined to meet the precise adjustment of the trimming width, avoid the instantaneous increase in unit tension and rolling force, thereby reducing the occurrence of strip breakage accidents; at the same time, the appropriate crescent moon shearing position can improve the head shape of the strip steel and also avoid the phenomenon of strip steel breakage after threading, improving the rolling quality of the strip steel.

[0210] Although the preferred embodiments of the present invention have been described, those skilled in the art can make additional changes and modifications to these embodiments once they know the basic creative concept. Therefore, the appended claims are intended to be construed as including the preferred embodiments and all changes and modifications falling within the scope of the present invention.

[0211] The above is only a preferred embodiment of the present invention and is not used to limit the protection scope of the present invention. Any modifications, equivalent replacements, and improvements made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A method for controlling the crescent cutting of a strip steel, characterized in that: The method comprises: Determine the crescent cutting position according to the width of the previous steel strip of the current weld, the width of the next steel strip, the minimum allowable trimming amount of the single-side trimming, the maximum depth of the shear blade, the trimming mark of the previous steel strip, and the trimming mark of the next steel strip; Determine a strip speed control mode based on the crescent cutting position, the previous strip width and the next strip width; The crescent shears are controlled to perform crescent cutting operation on the strip based on the crescent cutting position and the strip speed control mode.

2. The method according to claim 1, characterized in that The method of determining the crescent cutting position according to the width of the previous steel strip of the current weld, the width of the next steel strip, the minimum allowable trimming amount of the single-side trimming, the maximum depth of the shear blade, the trimming mark of the previous steel strip, and the trimming mark of the next steel strip includes: Determine the strip width difference and the strip width change mark according to the previous strip width and the next strip width of the current weld, and determine the strip depth difference according to the minimum trimming amount allowed for single-side trimming and the maximum depth of the shear blade; If it is determined that the strip width difference is less than or equal to the strip depth difference, the strip width change mark is the first mark, and the trimming mark of the previous roll of strip steel and the trimming mark of the next roll of strip steel are both trimming, then it is determined that the crescent cutting position is before the strip weld; the first mark is narrow to wide and the trimming parameters need to be adjusted; If it is determined that the strip width difference is less than or equal to the strip depth difference, the strip width change mark is the same width, and the trimming mark of the previous roll of strip and the trimming mark of the next roll of strip are both trimming, it is determined that the crescent cutting operation does not need to be performed; If it is determined that the strip width difference is less than or equal to the strip depth difference, the strip width change mark is the second mark, and the trimming mark of the previous roll of strip steel and the trimming mark of the next roll of strip steel are both trimming, then it is determined that the crescent cutting position is before the strip weld; the second mark is that the width becomes narrower and the trimming parameters need to be adjusted; If it is determined that the strip width difference is less than or equal to the strip depth difference, the strip width change mark is the first target change mark, the trimming mark of the previous roll of strip is trimming, and the trimming mark of the next roll of strip is no trimming, then it is determined that the crescent cutting position is before the strip weld; the first target change mark is the first mark or the second mark or the third mark; the third mark is the same width and the trimming parameters do not need to be adjusted.

3. The method according to claim 1, characterized in that The method of determining the crescent cutting position according to the width of the previous steel strip of the current weld, the width of the next steel strip, the minimum allowable trimming amount of the single-side trimming, the maximum depth of the shear blade, the trimming mark of the previous steel strip, and the trimming mark of the next steel strip includes: Determine the strip width difference and the strip width change mark according to the previous strip width and the next strip width of the current weld, and determine the strip depth difference according to the minimum trimming amount allowed for single-side trimming and the maximum depth of the shear blade; If it is determined that the strip width difference is less than or equal to the strip depth difference, the strip width change mark is the second target change mark, the trimming mark of the previous roll of strip steel is not trimming, and the trimming mark of the next roll of strip steel is trimming, then it is determined that the crescent cutting position is before the strip weld; the second target change mark is the first mark or the third mark; If it is determined that the strip width difference is less than or equal to the strip depth difference, the strip width change mark is the second mark, the trimming mark of the previous roll of strip is not trimming, and the trimming mark of the next roll of strip is trimming, then it is determined that the crescent cutting position is after the strip weld; If it is determined that the strip width difference is less than or equal to the strip depth difference, and the trimming mark of the previous roll of strip and the trimming mark of the next roll of strip are both non-trimming, it is determined that there is no need to perform the crescent cutting operation.

4. The method according to claim 1, characterized in that The method of determining the crescent cutting position according to the width of the previous steel strip of the current weld, the width of the next steel strip, the minimum allowable trimming amount of the single-side trimming, the maximum depth of the shear blade, the trimming mark of the previous steel strip, and the trimming mark of the next steel strip includes: Determine the strip width difference and the strip width change mark according to the previous strip width and the next strip width of the current weld, and determine the strip depth difference according to the minimum trimming amount allowed for single-side trimming and the maximum depth of the shear blade; If it is determined that the strip width difference is greater than the strip depth difference and less than or equal to a preset threshold, the strip width change mark is the first mark, and the trimming mark of the previous roll of strip steel and the trimming mark of the next roll of strip steel are both trimming, then it is determined that the crescent cutting position is before the strip weld; If it is determined that the strip width difference is greater than the strip depth difference and less than or equal to a preset threshold, the strip width change mark is the second mark, and the trimming mark of the previous roll of strip steel and the trimming mark of the next roll of strip steel are both trimming, then it is determined that the crescent cutting position is after the strip weld; If it is determined that the strip width difference is greater than the strip depth difference and is less than or equal to a preset threshold, the strip width change mark is the third target mark, the trimming mark of the previous roll of strip is trimming, and the trimming mark of the next roll of strip is no trimming, then it is determined that the crescent cutting position is before the strip weld; the third target mark is the first mark or the second mark.

5. The method according to claim 4, characterized in that The method further comprises: If it is determined that the strip width difference is greater than the strip depth difference and less than or equal to a preset threshold, the strip width change mark is the first mark, the trimming mark of the previous roll of strip is not trimming, and the trimming mark of the next roll of strip is trimming, then it is determined that the crescent cutting position is before the strip weld; If it is determined that the strip width difference is greater than the strip depth difference and less than or equal to a preset threshold, the strip width change mark is the second mark, the trimming mark of the previous roll of strip is not trimming, and the trimming mark of the next roll of strip is trimming, then it is determined that the crescent cutting position is after the strip weld; If it is determined that the strip width difference is greater than the strip depth difference and is less than or equal to a preset threshold, the trimming mark of the previous roll of strip is not trimming, and the trimming mark of the next roll of strip is not trimming, it is determined that there is no need to perform the crescent cutting operation.

6. The method according to claim 1, characterized in that The method of determining the crescent cutting position according to the width of the previous steel strip of the current weld, the width of the next steel strip, the minimum allowable trimming amount of the single-side trimming, the maximum depth of the shear blade, the trimming mark of the previous steel strip, and the trimming mark of the next steel strip includes: Determine the strip width difference and the strip width change mark according to the previous strip width and the next strip width of the current weld, and determine the strip depth difference according to the minimum trimming amount allowed for single-side trimming and the maximum depth of the shear blade; If it is determined that the strip width difference is greater than a preset threshold, the strip width change mark is the first mark, the trimming mark of the previous roll of strip is trimming, and the trimming mark of the next roll of strip is trimming, then it is determined that the crescent cutting position is before the strip weld; If it is determined that the strip width difference is greater than a preset threshold, the strip width change mark is the second mark, the trimming mark of the previous roll of strip is trimming, and the trimming mark of the next roll of strip is trimming, then it is determined that the crescent cutting position is before the strip weld; If it is determined that the strip width difference is greater than a preset threshold, the strip width change mark is wide to narrow, the trimming mark of the previous roll of strip is trimming, and the trimming mark of the next roll of strip is trimming, then it is determined that the crescent cutting position is after the strip weld; If it is determined that the strip width difference is greater than a preset threshold, the strip width change mark is a fourth target mark, the trimming mark of the previous roll of strip steel is trimming, and the trimming mark of the next roll of strip steel is non-trimming, it is determined that there is no need to perform the crescent cutting operation; the fourth target mark includes: the first mark or the second mark; If it is determined that the strip width difference is greater than a preset threshold, the strip width change mark is the first mark, the trimming mark of the previous roll of strip steel is not trimming, and the trimming mark of the next roll of strip steel is trimming, it is determined that the crescent cutting operation does not need to be performed; If it is determined that the strip width difference is greater than a preset threshold, the strip width change mark is the second mark, the trimming mark of the previous roll of strip is no trimming, and the trimming mark of the next roll of strip is trimming, then it is determined that the crescent cutting position is after the strip weld.

7. The method according to any one of claims 3 to 6, characterized in that If it is determined that the crescent cutting position is behind the strip weld, the method further includes: Determine a first distance between the roll gap of the last frame and the mandrel on the inlet side; Determine the actual distance between the distal end of the crescent region and the weld according to the theoretical length of the crescent region and the theoretical distance between the distal end of the crescent region and the weld; Determining the rolling length of the crescent region after deformation according to the finished product thickness and raw material thickness of the strip steel; Determining whether it is necessary to compensate the crescent cutting position according to the rolling length of the deformed crescent area and the first distance, and if necessary, determining the distance compensation value according to the distance between the racks, the finished product thickness of the strip steel and the raw material thickness; The actual cutting position of the crescent area is determined according to the theoretical distance between the far end of the crescent area and the weld and the distance compensation value.

8. The method according to claim 1, characterized in that The determining of the strip speed control mode based on the crescent cutting position, the previous strip width and the next strip width comprises: If it is determined that the width of the previous roll of steel strip is smaller than the width of the next roll of steel strip and the crescent cut position is before the weld, the speed of the steel strip is controlled to decrease from the first running speed to the second running speed until the crescent cut position of the previous roll of steel strip reaches the crescent shear, and the speed of the steel strip is controlled to decrease to zero; If it is determined that the width of the previous roll of strip steel is greater than the width of the next roll of strip steel and the crescent cutting position is after the weld, the strip speed is controlled to drop from the first running speed to the second running speed until the crescent cutting position of the next roll of strip steel reaches the crescent shear, and the strip speed is controlled to drop to zero.

9. The method according to claim 1, characterized in that The determining of the strip speed control mode based on the crescent cutting position, the previous strip width and the next strip width comprises: If it is determined that the width of the previous steel strip is greater than the width of the next steel strip and the trimming marks of the previous steel strip and the next steel strip are both non-trimming, controlling the speed of the steel strip to pass through the crescent shear at the first operating speed; If it is determined that the width of the previous steel strip is smaller than the width of the next steel strip, the trimming mark of the previous steel strip is not trimming and the trimming mark of the next steel strip is trimming, it is determined whether the weld seam cuts a crescent at the welding machine position, and if so, the speed of the steel strip is controlled to pass through the crescent shear at the first running speed; If it is determined that the width of the previous roll of steel strip is smaller than the width of the next roll of steel strip, and the trimming mark of the previous roll of steel strip and the trimming mark of the next roll of steel strip are both trimming, it is determined whether the weld cuts a crescent at the welding machine position. If so, the speed of the steel strip is controlled to pass through the crescent shear at the first operating speed.

10. A control device for cutting crescents in strip steel, characterized in that: The device comprises: The first determination unit is used to determine the crescent cutting position according to the previous steel strip width of the current weld, the next steel strip width, the minimum allowable trimming amount of single-side trimming, the maximum depth of the shear blade, the trimming mark of the previous steel strip, and the trimming mark of the next steel strip; A second determination unit, configured to determine a strip speed control mode based on the crescent cutting position, the previous strip width, and the next strip width; A control unit is used to control the crescent shear to perform a crescent cutting operation on the strip based on the crescent cutting position and the strip speed control mode.

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