Method, system and equipment for calculating inclination angle of pipe straightening roll and medium

Abstract

The invention provides a method for calculating the inclination angle of a pipe straightening roll, which comprises the following steps of: determining an iteration interval of the inclination angle of the pipe straightening roll, dispersing a pipe and the straightening roll, intersecting the dispersed pipe and the straightening roll to obtain a point set, fitting the point set to obtain a fitting curve, calculating the intersection depth, and judging the intersection depth with a first threshold value. When the cross-cutting depth is qualified, the contact chord length is calculated, the contact chord length meets the requirement, the iteration interval is further shortened, and finally the inclination angle of the pipe straightening roll is determined. And under the condition that the intersection cutting depth and the contact chord length are both met, optimization adjustment is further carried out, so that the inclination angle of the pipe straightening roll is optimal. By means of the calculation method, the pipes of various shapes and various sizes can be straightened, the calculation amount is relatively simple compared with an existing method, and the calculation speed is increased.

Description

Technical Field

[0001] The invention relates to the technical field of tube steel rolling, and in particular to a method, system, equipment and medium for calculating the inclination angle of a tube straightening roller. Background Art

[0002] As one of the important terminal products in the long rolling industry, the quality requirements of pipes for straightness, roundness, etc. have always been the focus of the industry. At present, inclined roller straightening machines are widely used at home and abroad as the main equipment for near-terminal processing of pipes to ensure quality. However, with the diversity of pipe specifications and the wear of straightening rollers, the inclined roller straightening machine cannot select the appropriate inclination angle to ensure sufficient contact effect, and cannot correct and optimize the control model, resulting in poor straightening effect or serious quality consequences such as inability to straighten.

[0003] In actual production, it is necessary to consider both the reasonable wear of the straightening roller and the bending of the pipe. On-site engineers usually use trial and error adjustment experiments, which is time-consuming, material-intensive and non-repeatable. There is currently a method for analytically solving the inclination angle of straightening rollers and straight steel pipes whose outer contours are regular geometric equations. This method has a narrow application range for straightening rollers and is not suitable for bent pipes. CN109530487B provides a method for calculating the inclination angle of the working rollers of a pipe straightening machine based on discrete optimization. The inclination angle is optimized by globally traversing the straightening rollers and the pipes to calculate the Euclidean distance between them. This method has a huge calculation scale and does not support straightening of bent pipes. Moreover, many straightening fits do not need to meet the established fit rate indicators. Summary of the invention

[0004] In view of the above-mentioned shortcomings of the prior art, the purpose of the present invention is to provide a method, system, equipment and medium for calculating the inclination angle of a pipe straightening roller, so as to solve the problems in the prior art such as poor straightening effect on bent pipes with different bending degrees.

[0005] To achieve the above-mentioned and other related purposes, the present invention provides a method for calculating the inclination angle of a tube straightening roller, comprising the following steps:

[0006] S1, determine the iteration interval of the inclination angle of the tube straightening roller;

[0007] S2, discretizing the pipe and the straightening roller respectively, intersecting the discretized pipe and the straightening roller to obtain a point set, and fitting the point set to obtain a fitting curve;

[0008] S3, calculating the intersection depth of the point set and the contact chord length of the fitting curve;

[0009] S4, obtaining the maximum intersection depth value among all intersection depths, comparing the maximum intersection depth value with a preset first threshold value, if the maximum intersection depth value is greater than or equal to the first threshold value, the requirement is not met, and the loop starts from step S1; if the maximum intersection depth value is less than the first threshold value, proceed to the next step;

[0010] S5, obtaining the contact chord length of the fitting curve, and comparing the contact chord length with a preset second threshold. If the contact chord length is less than the second threshold, the requirement is not met, and the loop starts from step S1; if the contact chord length is greater than or equal to the second threshold, proceed to the next step;

[0011] S6. Obtain the length of the iteration interval, and compare the length of the iteration interval with a preset third threshold. If the length of the iteration interval is greater than the third threshold, start the loop from step S1. If the length of the iteration interval is less than or equal to the third threshold, terminate the calculation. At this time, the angle in the iteration interval is the inclination angle of the pipe straightening roller.

[0012] Furthermore, when the maximum intersection depth value and the contact chord length in steps S4 and S5 do not meet the requirements, the iteration interval is increased by the following steps:

[0013] Calculate the maximum intersection depth of the two endpoint values ​​of the inclination angle of the tube straightening roller in the previous iteration interval;

[0014] Compare the two groups of maximum intersection depths with the first threshold value respectively, select the corresponding inclination angle of the group with the smaller difference, and then adjust the value of the other inclination angle until the maximum intersection depths when the inclination angles of the straightening roller are at the two end points are both less than the first threshold value;

[0015] When the two sets of maximum intersection depths are both less than the first threshold, the contact chord lengths when the straightening roller inclination angles are at the two endpoint values ​​are calculated, a set of inclination angles corresponding to the contact chord lengths are selected, and then the other inclination angle value is adjusted until the contact chord lengths are greater than the second threshold when the straightening roller inclination angles are at the two endpoint values.

[0016] Furthermore, the step S2 of discretizing the pipes specifically includes:

[0017] Get the first center angle α corresponding to the part where the pipe contacts the straightening roller P And the contact length L between the pipe and the straightening roller P ;

[0018] The first central angle α P Divide the pipe into m parts along its circumference, and form m mother curves on the outer contour of the pipe;

[0019] The segmented reference length of the pipe is obtained according to the span and height difference between adjacent straightening roller pairs;

[0020] The contact length L will be along the axis of the tube. P Each mother curve on is divided into n segments according to the segment reference length.

[0021] Furthermore, the step S2 discretizes the straightening roller, obtains a point set after the pipe and the straightening roller intersect, and obtains a fitting curve after fitting the point set, which specifically includes the following steps:

[0022] Get the second center angle α corresponding to the contact part between the straightening roller and the pipe S ;

[0023] The outer contour generatrix takes the straightening roller axis as the rotation axis and rotates the second central angle α S The angle forms a rotating surface, and the two ends of the straightening roller are at the second center angle α S Form two fan-shaped surfaces and the second central angle α S The edge forms two axial sections, and the revolving surface, the fan-shaped surface and the broken axial surface form a closed model;

[0024] Divide the surface of the closed model into several patches;

[0025] Each line segment is mapped to a corresponding face patch. Each line segment intersects with the face patch to form a first intersection point and a second intersection point. The first intersection point and the second intersection point form a pair of point sets.

[0026] Furthermore, the surface of the closed model is divided into a number of facets, specifically including: discretizing the axial section and the rotation surface along the axial direction of the straightening roller according to a first length, and discretizing the rotation surface and the fan-shaped surface along the circumferential direction of the straightening roller at a first angle.

[0027] Furthermore, the surface of revolution is discretized to form a number of quadrilateral patches, and the diagonal lines of each quadrilateral patch on the surface of revolution are connected to form a number of triangular patches, and the node normal vectors of all the triangular patches are the same.

[0028] Furthermore, the rotating surface and the sector surface are discretized at a first angle along the circumferential direction of the straightening roller, including that the first angle is calculated by the formula ε=[α-2sin(α / 2)] / α, where ε represents a preset arc allowable error and α represents the first angle.

[0029] On the other hand, the present application also provides a system for adjusting the inclination angle of a tube straightening roller, wherein the adjustment system adopts the inclination angle calculation method described above, and comprises:

[0030] Iteration module, used to determine the initial iteration interval of the straightening roller inclination angle, determine the iteration interval of the straightening roller inclination angle after subsequent adjustment, and also used to obtain the first center angle α corresponding to the contact part between the pipe and the straightening roller P And the second center angle α corresponding to the contact part between the straightening roller and the pipe S ;

[0031] Model module, used for rotating the outer contour generatrix around the straightening roller axis and rotating the second central angle α S The angle forms a rotating surface, and the two ends of the straightening roller are at the second center angle α S Form two fan-shaped surfaces and the second central angle α S The edge forms two axial sections, and the revolving surface, the fan-shaped surface and the broken axial surface form a closed model;

[0032] Discrete module, used to discretize the pipe into several line segments, and discretize the closed model into multiple facets;

[0033] The fitting module is used to map each line segment to a patch, each line segment intersects with the patch to form a first intersection point and a second intersection point, the first intersection point and the second intersection point form a pair of point sets; and all point sets are fitted to form a fitting curve

[0034] A calculation module, used to calculate the intersection depth of each point set and the contact chord length of the fitting curve, wherein the intersection depth is the distance between the midpoint of the point set and the outer contour line of the straightening roller;

[0035] The judgment module is used to compare the intersection depth with a first threshold, compare the contact chord length of the fitting curve with a second threshold, and compare the iteration interval length with a third threshold.

[0036] On the other hand, the present application also provides an electronic terminal, comprising: a processor, a memory, and a computer program stored in the memory and executable on the processor, wherein the processor implements the steps of the method for calculating the inclination angle of the pipe straightening roller described above when executing the computer program.

[0037] On the other hand, the present application also provides a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the steps of the method for calculating the inclination angle of the pipe straightening roller described above.

[0038] As described above, the present invention has the following beneficial effects: the present invention first determines an iteration interval of the inclination angle of the straightening roller, analyzes the situation of the inclination angle of the pipe straightening roller at the two end points of the iteration interval, obtains the intersection depth and contact chord length, and further optimizes and adjusts the inclination angle of the pipe straightening roller to the optimal value when the intersection depth and contact chord length meet the conditions. The calculation method provided by the present invention can straighten pipes of various shapes and sizes, and the calculation amount of the present application is relatively simple compared with the existing method, which improves the calculation speed. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] Figure 1 A flow chart showing a method for calculating the inclination angle of a tube straightening roller provided by the present invention;

[0040] Figure 2 It is a schematic diagram of the structure when the inclination angle between the pipe and the straightening roller is 0°;

[0041] Figure 3 It is a schematic diagram of the structure when the inclination angle between the pipe and the straightening roller is 45°;

[0042] Figure 4 It is a schematic diagram of the structure when the inclination angle between the pipe and the straightening roller is 90°;

[0043] Figure 5 It is a schematic diagram of the structure when the pipe intersects with the straightening roller;

[0044] Figure 6 It is a schematic diagram of the discretization structure of the closed model of the straightening roller;

[0045] Figure 7 Schematic diagram of tilt angle contact error.

[0046] Part Number Description

[0047] 1- pipe, 2- straightening roller, 21- shaft end face, 22- rotating surface, 23- sector surface. DETAILED DESCRIPTION

[0048] The following describes the embodiments of the present invention through specific examples, and those skilled in the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and the details in this specification can also be modified or changed in various ways based on different viewpoints and applications without departing from the spirit of the present invention.

[0049] See also Figure 1 The present invention provides a method for calculating the inclination angle of a tube straightening roller, comprising the following steps:

[0050] S1. Determine the iteration interval of the inclination angle of the tube straightening roller.

[0051] First, determine the initial iteration interval of the tube straightening roller inclination angle like Figure 2 As shown in the figure, when the axis of the tube 1 is parallel to the axis of the straightening roller 2 in the plane projection, the tube 1 cannot be straightened by contacting the straightening roller 2 because the diameter of the two ends of the straightening roller 2 is larger than the middle. Figure 3 As shown in the figure, when the axis of the tube 1 is perpendicular to the axis of the straightening roller 2 in the plane projection, only the middle point of the straightening roller 2 straightens the tube 1. Therefore, the iteration interval of the inclination angle of the tube straightening roller is generally [0,90]. You can also reduce the iteration interval at the beginning based on experience to reduce the number of iterations.

[0052] Straightening rollers are arranged on both the upper and lower sides of the pipe. The present invention separates the angles between the straightening rollers on both sides and the pipe for simulation adjustment.

[0053] S2. The pipe and the straightening roller are discretized respectively, and a point set is obtained after the pipe and the straightening roller intersect. The point set is fitted to obtain a fitting curve.

[0054] The straightening roller and the pipe are intersected according to the two endpoint values ​​of the iteration interval, and the situation of each endpoint value is analyzed.

[0055] Set the inclination angle of the tube straightening roller to two end values Simulation calculations are performed at the same time, and based on the results, the range of the inclination angle of the pipe straightening roller can be further determined in which direction to adjust next time.

[0056] The pipe is divided into several line segments along the pipe axis, and the straightening roller is divided into multiple surface patches.

[0057] In order to reduce the amount of calculation, when calculating the pipe and the straightening roller, the pipe is first divided into several small sections, and the straightening roller is divided into multiple slices.

[0058] Only part of the pipe contacts the straightening roller on one side, and the other part contacts the straightening roller on the other side. Therefore, when adjusting the inclination angle of the pipe straightening roller, the contact part should be divided first.

[0059] The inclination angle of the tube straightening roller is different, and the length of the tube at the straightening roller is different, that is, the contact length L between the tube and the straightening roller. P Different, the first central angle α corresponding to the contact part between the pipe and the straightening roller P Also different.

[0060] The length of the straightening roller in the working space is L S , then the contact length between the pipe and the straightening roller is L P =L S cosβ, where β is the angle between the tube axis and the straightening roller axis projected onto the plane.

[0061] Before dividing the pipe, first obtain the first central angle α corresponding to the part of the pipe in contact with the straightening roller. P And the contact length L between the pipe and the straightening roller P .

[0062] In principle, the pipe can be divided into two parts along its central axis, that is, the pipe located above the central axis contacts the upper straightening roller, and the pipe located below the central axis contacts the lower straightening roller. P It can be 90°.

[0063] However, in actual application, the straightening roller does not wrap the pipe, so the first central angle α P It is usually less than 90°. The first central angle α P The specific size is related to the diameter of the pipe and the size of the straightening roller.

[0064] The first central angle α P The tube is divided into m parts along the circumference, forming m mother curves on the outer contour of the tube; the first central angle α P The size of determines the progress of subsequent calculations. The first central angle α P The smaller it is, the higher the accuracy.

[0065] According to the span l and height difference H between adjacent straightening roller pairs SP The distance between adjacent straightening roller pairs is L. SP , then the span between adjacent straightening roller pairs is l = 2L SP , the maximum deflection f between adjacent straightening roller pairs max =H SP , the curvature is calculated based on the deflection, and then the segment reference length is calculated based on the curvature.

[0066] The contact length L will be along the axis of the tube. P Each generatrix on the straightening roller is divided into n segments according to the segment reference length. The pipe is divided along the generatrix direction of the pipe, and the segment reference length refers to the length of each segment of the generatrix. This is equivalent to dividing the part of the pipe that contacts the straightening roller into m*n line segments.

[0067] Similarly, when simulating the straightening roller, in order to reduce the division of the entire straightening roller and reduce the workload, the second center angle α corresponding to the contact part between the straightening roller and the pipe is first obtained. S .

[0068] The outer contour generatrix takes the straightening roller axis as the rotation axis and rotates the second central angle α S The angle forms a rotating surface 22, and the two ends of the straightening roller are at the second center angle α S Two fan-shaped surfaces 23 are formed and the second central angle α S The edge forms two axial sections 21, and the revolving surface 22, the sector surface 23 and the axial section 21 form a closed model with a closed surface.

[0069] The existing method only discretizes the outer contour surface of the straightening roller. When the discrete line segments of the tube are mapped to the outer contour surface of the straightening roller, the number of intersections may be an odd number because the outer contour of the straightening roller is not closed, that is, only one intersection point of some intersecting line segments is captured. This exception leads to poor robustness of the algorithm.

[0070] The present invention obtains a closed model by combining a revolving surface 22, two sector-shaped surfaces 23 and two end shaft end surfaces 21 into a closed surface.

[0071] The surface of the closed model is divided into several patches, that is, the five surfaces of the surface of the closed model are all discretized. Specifically, the axial section and the rotating surface 22 are discretized according to the first length along the axial direction of the straightening roller, and the rotating surface 22 and the fan-shaped surface 23 are discretized at a first angle along the circumferential direction of the straightening roller. Thus, trapezoidal patches are formed on the two axial end faces 21, patches close to triangles are formed on the two fan-shaped surfaces 23, and quadrilateral patches are formed on the rotating surface 22. Triangular patches are more convenient to calculate, so the diagonals of the quadrilateral patches on the axial end faces 21 and the rotating surface 22 are connected to form triangular patches, and the normal vectors of all patch nodes are simultaneously facing the inside or the outside of the closed model, that is, the normal vectors of each face of each closed model are either all facing the inside of the closed model or all facing the closed outside, and the normal vector represents the local direction of the surface at that point. The normal vector algorithm of the triangle is simple, so all patches are discretized into triangles.

[0072] The shorter the first length, the higher the progress. The straightening roller can be discretized along the circumference according to the minimum segment length. The first angle must meet the arc tolerance. The first angle is calculated by the formula ε-[α-2sin(α / 2)] / α, where ε represents the preset arc tolerance and α represents the first angle. For example, if the arc tolerance is set to 0.01%, the corresponding first angle α = 2.8°. Since the second center angle α is generally ε is 90°, so α is taken as 2.5°. That is, when the straightening roller is discretized in the circumferential direction, it is discretized at 2.5°. The same algorithm can also be used for the discretization of the pipe in the circumferential direction.

[0073] Each line segment is mapped to a corresponding face patch. Each line segment intersects with the face patch to form a first intersection point and a second intersection point. The first intersection point and the second intersection point form a pair of point sets.

[0074] The solution to the intersection of a space line segment and a face can be achieved by using the vector intersection algorithm of a straight line and an infinite plane, as well as the area method, space vector method, and centroid method to determine the intersection point in a finite plane.

[0075] The multi-line segment intersects with the partially closed outer contour surface of the straightening roller to obtain a series of intersection points. Since the straightening roller is discretized into a closed spatial surface patch, the two adjacent points are a pair of point sets that penetrate into and out of the straightening roller. All point sets are fitted to obtain the fitting curve.

[0076] S3. Calculate the intersection depth of the point set and the contact chord length of the fitting curve.

[0077] The intersection depth of each point set is calculated. The intersection depth is the distance between the midpoint of the point set and the outer contour of the straightening roller. The intersection depth can be used to determine whether the pipe and the straightening roller effectively intersect. The length of the fitting curve is the contact chord length.

[0078] S4. Obtain the maximum intersection depth value among all intersection depths, and compare the maximum intersection depth value with the preset first threshold value. If the maximum intersection depth value is greater than or equal to the first threshold value, the requirement is not met, and the iteration interval of the straightening roller inclination angle is modified, and the loop starts from step S1; if the maximum intersection depth value is less than the first threshold value, proceed to the next step.

[0079] An intersection depth is calculated for each point set, and all intersection depths are compared with the preset first threshold to determine whether the pipe and the straightening roller effectively intersect. As long as the maximum value of all intersection depths is less than the first threshold, the remaining intersection depths must be less than the first threshold, indicating that the inclination angle of the pipe straightening roller at this moment meets the requirements.

[0080] Specifically, after first determining the initial iteration interval of the inclination angle of the tube straightening roller, the two endpoint values ​​are subsequently changed toward the other side during the iteration process. For example, the maximum intersection depth at the two endpoint values ​​of the initial iteration interval is first calculated, and the maximum intersection depth at the two endpoint values ​​is compared with the first threshold. The inclination angle corresponding to a group with a smaller difference between the maximum intersection depth and the first threshold indicates that it is closer to the optimal inclination angle. Therefore, when increasing the adjustment, the inclination angle corresponding to a group with a smaller difference between the maximum intersection depth and the first threshold can be kept unchanged first, and the endpoint value with a larger difference between the maximum intersection depth and the first threshold can be changed. Finally, until the maximum intersection depth at the two endpoint values ​​is less than the first threshold, the judgment can be made backward.

[0081] The first threshold is equivalent to the contact criterion e that the pipe and the straightening roller form an effective intersection. rc , e rc Contact criterion rc is the maximum distance of the arc chord corresponding to the discretization of the straightening roller at the first angle. Figure 7 As shown, α is the first discrete angle, is the arc length of the arc corresponding to the first angle, is the length of the chord corresponding to the arc length, e rc is the distance between the corresponding chord and the corresponding arc. The smallest diameter of the middle section of the straightening roller is Ds, then Wherein α represents the first angle of the straightening roller discretized along the circumferential direction under the condition that the arc error is allowed.

[0082] S5. Obtain the contact chord length of the fitting curve, and compare the contact chord length with a preset second threshold. If the contact chord length is less than the second threshold, the requirement is not met, and the iteration interval of the straightening roller inclination angle is modified, and the cycle starts from step S1; if the contact chord length is greater than or equal to the second threshold, proceed to the next step.

[0083] Specifically, when the two sets of maximum intersection depths are both less than the first threshold, the contact chord lengths when the straightening roller inclination angles are at the two endpoint values ​​are calculated, a set of inclination angles corresponding to the contact chord lengths are selected, and then the other inclination angle value is adjusted until the contact chord lengths are greater than the second threshold when the straightening roller inclination angles are at the two endpoint values.

[0084] The longer the contact chord length is, the longer the contact length between the pipe and the straightening roller is, and the better the straightening effect is. Specifically, after first determining the initial iteration interval of the inclination angle of the pipe straightening roller, the two endpoint values ​​are subsequently changed toward the other side during the iteration process. For example, the contact chord lengths at the two endpoint values ​​of the initial iteration interval are first calculated, and the contact chord lengths at the two endpoint values ​​are compared with the second threshold. The inclination angle corresponding to a group with a larger difference between the contact chord length and the second threshold indicates that it is closer to the optimal inclination angle. Therefore, when increasing the contact chord length, the inclination angle corresponding to a group with a larger difference between the contact chord length and the second threshold can be kept unchanged first, and the endpoint value with a smaller difference between the contact chord length and the second threshold can be changed. Finally, until the contact chord lengths at the two endpoint values ​​are greater than the second threshold, the judgment can be made backwards.

[0085] S6, obtaining the length of the iteration interval, comparing the length of the iteration interval with the preset third threshold, if the length of the iteration interval is greater than the third threshold, modifying the iteration interval of the straightening roller inclination angle, starting the loop from step S1, if the length of the iteration interval is less than or equal to the third threshold, then terminating the calculation, and the angle in the iteration interval at this time is the optimal inclination angle β of the tube straightening roller. At this time, the two endpoint values ​​of the iteration interval and one of the values ​​within the range of the two endpoints is the inclination angle of the tube straightening roller, preferably the average of the two endpoint values.

[0086] When the contact chord lengths corresponding to the two endpoint values ​​calculated at step S6 are greater than the second threshold, it means that the angles in the iteration interval at this time can meet the requirements. In order to obtain the optimal inclination angle, the two endpoint values ​​are subtracted to obtain the iteration interval length, and the iteration interval length is compared with the third threshold to obtain the optimal inclination angle. For example, if the third threshold is 1, the iteration ends only when the difference between the two endpoint values ​​in the iteration interval after the iteration is less than or equal to 1. At this time, any angle in the iteration interval can be used as the inclination angle of the pipe straightening roller. Of course, the average of the two endpoint values ​​is better.

[0087] In the process of iterating the iteration interval, a new inclination angle can be set within the iteration interval by using methods such as binary search and Newton tangent method for the next iteration. For example, binary search is used for scaling, and when the iteration interval of the tube straightening roller inclination angle is determined to be [20,50], then [35,50], [35,42.5], [35,38.75], [35,36.88], [35,35.94], the third threshold value is set to 1, 35.94-35=0.94<1, so if the conditions are met, the tube straightening roller inclination angle can be 35°, 35.94°, or one of the angles between 35° and 35.94°, preferably (35+35.94) / 2=35.787°.

[0088] On the other hand, the present invention further provides a system for adjusting the inclination angle of a tube straightening roller, wherein the adjustment system adopts the above-mentioned inclination angle calculation method, and comprises:

[0089] Iteration module, used to determine the initial iteration interval of the straightening roller inclination angle, determine the iteration interval of the straightening roller inclination angle after subsequent adjustment, and also used to obtain the first center angle α corresponding to the contact part between the pipe and the straightening roller P And the second center angle α corresponding to the contact part between the straightening roller and the pipe S .

[0090] The iteration module also reduces the range of the iteration interval during the iteration of the iteration interval. P and the second central angle α S The size of is 90°, and the value range of the second central angle is generally The value range of the first center angle of the pipe is

[0091] Model module, used for rotating the outer contour generatrix around the straightening roller axis and rotating the second central angle α S The angle forms a rotating surface 22, and the two ends of the straightening roller are at the second center angle α S Two fan-shaped surfaces 23 are formed and the second central angle α S The edge forms two axial sections, and the rotating surface 22, the fan-shaped surface 23 and the broken axis surface form a closed model. After the parts of the pipe and the straightening roller that need to be discrete are determined, a closed model is established for the parts of the straightening roller that need to be discrete.

[0092] The discrete module is used to discretize the pipe into several line segments and discretize the closed model into multiple facets. When discretizing the pipe, it is first discretized along the generatrix of the pipe at a certain angle, and then the segment reference length is determined according to the spacing between adjacent straightening roller pairs and the height difference between adjacent straightening roller pairs. The pipe is divided into multiple segments along the axial direction of the pipe according to the segment reference length.

[0093] The surface of the closed model of the entire closed model of the straightening roller is discretized so that each surface is discretized into a triangle. The angle of the straightening roller when being discretized along the circumferential direction satisfies the arc line allowable error.

[0094] The fitting module is used to map each discretized line segment to a face patch, each line segment intersects with the face patch to form a first intersection point and a second intersection point, the first intersection point and the second intersection point form a pair of point sets; and fit all point sets to form a fitting curve.

[0095] The calculation module is used to calculate the intersection depth of each point set and the contact chord length of the fitting curve. The intersection depth is the distance between the midpoint of the point set and the outer contour line of the straightening roller.

[0096] The judgment module is used to compare the intersection depth with a first threshold, compare the contact chord length of the fitting curve with a second threshold, and compare the iteration interval length with a third threshold.

[0097] On the other hand, the present application also provides an electronic terminal, comprising: a processor, a memory, and a computer program stored in the memory and executable on the processor, wherein when the processor executes the computer program, the steps of the method for calculating the inclination angle of the pipe straightening roller are implemented.

[0098] On the other hand, the present application also provides a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the steps of the above-mentioned method for calculating the inclination angle of the pipe straightening roller.

[0099] It should be noted that the computer-readable storage medium shown in the present invention may be a computer-readable signal medium or a computer-readable storage medium or any combination of the above two. The computer-readable storage medium may be, for example, but not limited to, an electrical, magnetic, optical, electromagnetic, infrared, or semiconductor system, device or device, or any combination of the above. More specific examples of computer-readable storage media may include, but are not limited to: an electrical connection with one or more wires, a portable computer disk, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), an optical fiber, a portable compact disk read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination of the above. In the present invention, a computer-readable storage medium may be any tangible medium containing or storing a program that can be used by or in combination with an instruction execution system, device or device. In the present invention, a computer-readable signal medium may include a data signal propagated in a baseband or as part of a carrier wave, which carries a computer-readable program code. This propagated data signal may take a variety of forms, including but not limited to electromagnetic signals, optical signals, or any suitable combination of the above. Computer-readable signal media may also be any computer-readable medium other than computer-readable storage media, which may send, propagate or transmit a program for use by or in conjunction with an instruction execution system, apparatus or device. The program code contained on the computer-readable medium may be transmitted using any appropriate medium, including but not limited to: wireless, wire, optical cable, RF, etc., or any suitable combination of the above.

[0100] The flow chart and block diagram in the accompanying drawings illustrate the possible architecture, function and operation of the system, method and computer program product according to various embodiments of the present invention. In this regard, each box in the flow chart or block diagram can represent a module, a program segment, or a part of a code, and the above-mentioned module, program segment, or a part of a code contains one or more executable instructions for realizing the specified logical function. It should also be noted that in some alternative implementations, the functions marked in the box can also occur in a different order from the order marked in the accompanying drawings. For example, two boxes represented in succession can actually be executed substantially in parallel, and they can sometimes be executed in the opposite order, depending on the functions involved. It should also be noted that each box in the block diagram or flow chart, and the combination of the boxes in the block diagram or flow chart can be implemented with a dedicated hardware-based system that performs a specified function or operation, or can be implemented with a combination of dedicated hardware and computer instructions.

[0101] The units involved in the embodiments of the present invention may be implemented by software or hardware, and the units described may also be arranged in a processor. The names of these units do not, in some cases, limit the units themselves. The units or modules described may also be arranged in a processor, for example, may be described as: a processor includes a data acquisition module, a first processing module, a second processing module, and a result generation module. The names of these units or modules do not, in some cases, limit the units or modules themselves.

[0102] The above description is only a preferred embodiment of the present application and an explanation of the technical principles used. Those skilled in the art should understand that the scope of the invention involved in the present application is not limited to the technical solution formed by a specific combination of the above technical features, but should also cover other technical solutions formed by any combination of the above technical features or their equivalent features without departing from the inventive concept. For example, the above features are replaced with the technical features with similar functions disclosed in this application (but not limited to) by each other.

Claims

1. A method for calculating the inclination angle of a tube straightening roller, characterized in that: The following steps are involved: S1, determine the iteration interval of the inclination angle of the tube straightening roller; S2, discretizing the pipe and the straightening roller respectively, intersecting the discretized pipe and the straightening roller to obtain a point set, and fitting the point set to obtain a fitting curve; S3, calculating the intersection depth of the point set and the contact chord length of the fitting curve; S4, obtaining the maximum intersection depth value among all intersection depths, comparing the maximum intersection depth value with a preset first threshold value, if the maximum intersection depth value is greater than or equal to the first threshold value, the requirement is not met, and the loop starts from step S1; if the maximum intersection depth value is less than the first threshold value, proceed to the next step; S5, obtaining the contact chord length of the fitting curve, and comparing the contact chord length with a preset second threshold. If the contact chord length is less than the second threshold, the requirement is not met, and the loop starts from step S1; if the contact chord length is greater than or equal to the second threshold, proceed to the next step; S6. Obtain the length of the iteration interval, and compare the length of the iteration interval with a preset third threshold. If the length of the iteration interval is greater than the third threshold, start the loop from step S1. If the length of the iteration interval is less than or equal to the third threshold, terminate the calculation. At this time, the angle in the iteration interval is the inclination angle of the pipe straightening roller.

2. The method for calculating the inclination angle of the tube straightening roller according to claim 1, characterized in that: When the maximum intersection depth value and contact chord length in steps S4 and S5 do not meet the requirements, the iteration interval is increased by the following steps: Calculate the maximum intersection depth of the two endpoint values ​​of the inclination angle of the tube straightening roller in the previous iteration interval; Compare the two groups of maximum intersection depths with the first threshold value respectively, select the corresponding inclination angle of the group with the smaller difference, and then adjust the value of the other inclination angle until the maximum intersection depths when the inclination angles of the straightening roller are at the two end points are both less than the first threshold value; When the two sets of maximum intersection depths are both less than the first threshold, the contact chord lengths when the straightening roller inclination angles are at the two endpoint values ​​are calculated, a set of inclination angles corresponding to the contact chord lengths are selected, and then the other inclination angle value is adjusted until the contact chord lengths are greater than the second threshold when the straightening roller inclination angles are at the two endpoint values.

3. The method for calculating the inclination angle of the tube straightening roller according to claim 1, characterized in that: The step S2 of discretizing the pipes specifically includes: Get the first center angle α corresponding to the part where the pipe contacts the straightening roller P And the contact length L between the pipe and the straightening roller P ; The first central angle α P Divide the pipe into m parts along its circumference, and form m mother curves on the outer contour of the pipe; The segmented reference length of the pipe is obtained according to the span and height difference between adjacent straightening roller pairs; The contact length L will be along the axis of the tube. P Each mother curve on is divided into n segments according to the segment reference length.

4. The method for calculating the inclination angle of the tube straightening roller according to claim 2, characterized in that: The step S2 discretizes the straightening roller, obtains a point set after the pipe and the straightening roller intersect, and obtains a fitting curve after fitting the point set, which specifically includes the following steps: Obtain a second center angle α5 corresponding to the contact portion between the straightening roller and the pipe; The outer contour generatrix takes the axis of the straightening roller as the rotation axis, rotates at the second center angle α5 to form a revolving surface, the two ends of the straightening roller form two fan-shaped surfaces at the second center angle α5, and the edges of the second center angle α5 form two axial sections, and the revolving surface, fan-shaped surface and axial section surface form a closed model; Divide the surface of the closed model into several patches; Each line segment is mapped to a corresponding face patch. Each line segment intersects with the face patch to form a first intersection point and a second intersection point. The first intersection point and the second intersection point form a pair of point sets.

5. The method for calculating the inclination angle of the tube straightening roller according to claim 4, characterized in that: The surface of the closed model is divided into a number of facets, specifically including: discretizing the axial section and the rotation surface along the axial direction of the straightening roller according to a first length, and discretizing the rotation surface and the fan-shaped surface along the circumferential direction of the straightening roller at a first angle.

6. The method for calculating the inclination angle of the tube straightening roller according to claim 5, characterized in that: After the surface of revolution is discretized, several quadrilateral patches are formed. The diagonals of each quadrilateral patch on the surface of revolution are connected to form several triangular patches. The normal vectors of all patch nodes are simultaneously directed to the inside or outside of the closed model.

7. The method for calculating the inclination angle of the tube straightening roller according to claim 5, characterized in that: in, The rotating surface and the sector surface are discretized at a first angle along the circumferential direction of the straightening roller, including that the first angle is calculated by the formula ε-[a-2sin(a / 2)] / a, wherein ε represents the allowable error of the arc and α represents the first angle.

8. A system for adjusting the inclination angle of a tube straightening roller, the system adopting the inclination angle calculation method according to any one of claims 1 to 7, characterized in that: include: Iteration module, used to determine the initial iteration interval of the straightening roller inclination angle, determine the iteration interval of the straightening roller inclination angle after subsequent adjustment, and also used to obtain the first center angle α corresponding to the contact part between the pipe and the straightening roller P and a second central angle α5 corresponding to the contact portion between the straightening roller and the pipe; Model module, used for the outer contour generatrix to take the straightening roller axis as the rotation axis, rotate the second center angle α5 to form a revolving surface, the two ends of the straightening roller to form two fan-shaped surfaces at the second center angle α5, and form two shaft sections at the edge of the second center angle α5, and form a closed model with the revolving surface, the fan-shaped surface and the shaft section surface; Discrete module, used to discretize the pipe into several line segments, and discretize the closed model into multiple facets; The fitting module is used to map each line segment to a patch, each line segment intersects with the patch to form a first intersection point and a second intersection point, the first intersection point and the second intersection point form a pair of point sets; and all point sets are fitted to form a fitting curve A calculation module, used to calculate the intersection depth of each point set and the contact chord length of the fitting curve, wherein the intersection depth is the distance between the midpoint of the point set and the outer contour line of the straightening roller; The judgment module is used to compare the intersection depth with a first threshold, compare the contact chord length of the fitting curve with a second threshold, and compare the iteration interval length with a third threshold.

9. An electronic terminal, characterized in that: include: A processor, a memory, and a computer program stored in the memory and executable on the processor, wherein when the processor executes the computer program, the steps of the method for calculating the inclination angle of the pipe straightening roller according to any one of claims 1 to 7 are implemented.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the program is executed by a processor, the steps of the method for calculating the inclination angle of the pipe straightening roller according to any one of claims 1 to 7 are implemented.

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