Punching device for power tower angle steel machining

Abstract

The application relates to the technical field of angle steel punching, in particular to a punching device for power tower angle steel machining, which comprises a feeding mechanism, the base body of which is a feeding frame, which is used for clamping and fixing the angle steel and controlling the feeding distance of the angle steel; a punching mechanism, the base body of which is a rack foundation, which is used for punching the angle steel by a plurality of punching punches based on different specifications of hole types; a correlation risk unit, which determines the punching risk state of the angle steel based on the maximum value of the correlation risk indexes of a plurality of adjacent hole pairs; a hole deformation unit, which determines the extrusion deformation degree of the hole-to-hole material under the current hole pair parameters in the punching process of the corresponding punching punch based on the dynamic punching impact amount, and adjusts the punching feed speed and the clamping pressure; a hole directional compensation unit, which determines the hole-to-hole deformation type of the current punching risk pair, and determines the auxiliary adjustment mode of the actual punching feed speed and the actual punching pressure. The application reduces the punching waste product rate caused by the tensile or extrusion deformation of the hole-to-hole material through hole-to-hole risk prediction.

Description

Technical Field

[0001] This invention relates to the field of angle steel punching technology, and in particular to a punching device for processing angle steel for power transmission towers. Background Technology

[0002] Angle steel is a commonly used basic material in the construction of power transmission towers, and the punching process of angle steel is a key step. Traditional punching equipment has many problems, such as low punching accuracy, low efficiency, and difficulty in changing molds, which cannot meet the needs of large-scale, high-precision angle steel processing.

[0003] Chinese Patent Publication No. CN114054581A discloses an angle steel punching machine, including a control box. Previously, processing six-meter angle steel materials involved multiple steps: punching, cutting, forming, and handling each six-meter section separately, often resulting in significant waste of scrap material. Now, based on the angle steel's width and the use of strip steel coils, the machine integrates the feeding of the entire coil, hole diameter and spacing, and length requirements. The process is programmed and uses a hydraulic punching and shearing system to feed the entire strip steel coil, deburring, chamfering, rolling, forming, punching screw holes, punching rivet holes, cutting corners, and cutting into a finished rolled angle steel product with punched holes, right-angled angle steel, and the length meeting customer requirements. Therefore, the aforementioned angle steel punching machine has the following problems: It is impossible to determine the material deformation risk between holes based on the design hole spacing and hole diameter of angle steel punching, and to switch differentiated punching control strategies based on the predicted hole deformation type to perform directional compensation for punching parameters. Summary of the Invention

[0004] To address this issue, the present invention provides a punching device for processing angle steel for power transmission towers, which overcomes the problem in the prior art that it is impossible to determine the material deformation risk between holes based on the design hole spacing and hole diameter for punching angle steel, and combines the predicted hole deformation type to switch differentiated punching control strategies to perform directional compensation for punching parameters.

[0005] To achieve the above objectives, the present invention provides a punching device for processing angle steel for power transmission towers, comprising: The feeding mechanism, whose base is a feeding frame, is used to clamp and fix the angle steel and control the feeding distance of the angle steel; The punching mechanism, whose base is a frame foundation, is used to control several punching punches to punch angle steel based on different hole shapes; The associated risk unit is used to determine the punching risk status of angle steel based on the maximum value of the associated risk index of several adjacent hole pairs, and to adjust the feeding speed curve and clamping force of the feeding mechanism and the punching sequence of the punching mechanism. The inter-hole deformation unit is used to respond to the punching risk state, determine the degree of extrusion deformation of the inter-hole material under the current hole pair parameters based on the punching dynamic impact amount, and adjust the punching feed speed and clamping pressure. The hole orientation compensation unit is used to determine the hole deformation type of the current punching risk pair based on the hole center distance deviation and hole edge protrusion, and to determine the auxiliary adjustment method of the actual punching feed speed and actual punching pressure. The negative feedback unit, which is connected to the associated risk unit, is used to adjust the risk index threshold range of the associated risk index based on the batch deformation index.

[0006] Furthermore, the punching mechanism is equipped with a marking device, a punching unit, and a cutting device along the angle steel feeding direction; The punch mounting base at the output end of the punching unit is equipped with several punching punches arranged side by side to accommodate different hole shapes. The cutting device is used to cut the angle steel to a fixed length after punching. The marking device is used to mark and stamp the angle steel before punching.

[0007] Furthermore, the associated risk unit includes: Angle steel parameter subunit is used to obtain the basic attribute parameters and punching characteristic parameters of the angle steel. The basic attribute parameters include material type, angle steel leg width and angle steel leg thickness, and the punching characteristic parameters include hole diameter and hole spacing. The associated risk index determination sub-unit is used to determine the net cross-sectional width between holes of the current hole to be punched based on the characteristic parameters of the hole to be punched in the angle steel, and to determine the associated risk index in combination with the basic attribute parameters of the angle steel. The risk status comparison subunit is used to determine the punching risk status of adjacent hole pairs of angle steel based on the comparison results between the maximum associated risk index value and the risk index threshold range. The punching risk adjustment subunit is used to adjust the feeding speed curve, clamping force, and angle steel punching sequence based on the punching risk status.

[0008] Furthermore, based on the fact that the associated risk index is below the risk index threshold range, the risk status comparison sub-unit determines that the angle steel is in the first punching risk state; Based on the correlation risk index being within the risk index threshold range, the risk status comparison subunit determines that the angle steel is in the second punching risk state. There is a risk of hole-to-punch deformation in the angle steel processing sequence. The punching risk adjustment subunit adjusts the feeding speed curve and clamping force. Based on the correlation risk index being higher than the risk index threshold range, the risk status comparison subunit determines that the angle steel is in the third punching risk state, and the punching risk adjustment subunit adjusts the punching sequence of the angle steel.

[0009] Furthermore, the inter-hole deformation unit includes: The impact determination subunit is used to determine the dynamic impact amount of punching based on the product of the extrusion influence range coefficient and the punch dynamic impact coefficient. The inter-hole deformation comparison sub-unit is used to determine whether the material between holes is at risk of extrusion deformation or to predict the deformation of the material between holes caused by punching, based on the comparison results of the dynamic impact amount and impact threshold of punching. The hole deformation adjustment subunit is used to determine the extent to decrease the punching feed speed and increase the clamping pressure based on the risk of extrusion deformation during punching or the deformation of the material between the holes caused by punching.

[0010] Furthermore, the impact determination subunit determines the extrusion influence range coefficient based on the ratio of the punch cross-sectional area of ​​the executing punch to the net cross-sectional width between the holes of the current risk hole pair; The impact determination subunit determines the dynamic impact coefficient of the punch based on the product of the total mass of the punch and the punching feed speed; The inter-hole deformation comparison sub-unit determines that the punch area or total moving mass poses a risk of extrusion deformation to the current inter-hole material based on the dynamic impact of punching being greater than or equal to the first impact threshold and less than the second impact threshold. The inter-hole deformation comparison sub-unit is based on the dynamic impact of punching being greater than or equal to the second impact threshold. It determines the total punching motion inertia of the current hole pair for the material deformation caused by punching the net cross-sectional width between the holes.

[0011] Furthermore, the inter-aperture directional compensation unit includes: The offset direction determination sub-unit is used to determine the actual hole center distance between two holes based on the installation spacing and hole displacement difference, and to determine the hole center distance deviation based on the actual hole center distance and the designed hole center distance. The hole edge protrusion determination sub-unit is used to determine the amount of hole edge protrusion based on the hole edge height value and the reference surface height; The inter-hole comparison sub-unit is used to determine the inter-hole deformation type of the current punching risk pair based on the comparison results of the hole center distance deviation and hole edge material protrusion with the hole center deviation threshold and hole edge protrusion threshold. The hole deformation compensation subunit is used to determine the adjustment amount of the actual punching feed speed or the actual punching pressure based on the type of hole deformation, and to assist in adjusting the actual punching pressure or the actual punching feed speed.

[0012] Furthermore, the offset direction determination subunit locates the current hole offset direction based on the actual hole center distance and the magnitude of the hole center distance deviation, wherein the hole displacement difference is the difference between the current hole displacement and the historical hole displacement. The hole-to-hole comparison sub-unit is determined to be a tensile deformation of the hole material based on the absolute value of the hole center distance deviation being greater than the hole center deviation threshold and the amount of material protrusion at the hole edge being less than or equal to the hole edge protrusion threshold. The inter-hole comparison sub-unit is determined to be an extrusion deformation of the hole edge material based on the absolute value of the hole center distance deviation being less than or equal to the hole center deviation threshold and the amount of protrusion of the hole edge material being greater than the hole edge protrusion threshold.

[0013] Furthermore, the hole deformation compensation subunit determines the blanking feed speed adjustment amount based on the tensile deformation of the material between holes, adjusts the actual blanking feed speed, and correspondingly assists in adjusting the actual blanking pressure. The hole deformation compensation subunit determines the punching pressure adjustment amount based on the extrusion deformation of the material at the hole edge, adjusts the actual punching pressure, and correspondingly assists in adjusting the actual punching feed speed.

[0014] Furthermore, the negative feedback unit includes: The deformation index determination subunit is used to determine the batch deformation index based on the average deviation and average protrusion of several second-risk state holes. The deformation index comparison subunit is used to determine the risk index threshold range based on the comparison results of batch deformation indices exceeding the quality target threshold. The negative feedback adjustment subunit is used to increase the upper limit of the risk index threshold range based on the fact that the risk index threshold range is too wide.

[0015] Compared with the prior art, the beneficial effects of the present invention are as follows: The present invention achieves precise feeding and positioning of angle steel through the cooperation of a servo motor, clamping components, and centering components in the feeding mechanism; it achieves adaptive punching of multiple hole types through at least three different types of punching punches arranged side-by-side and a proportional overflow valve in the punching mechanism; it determines the punching risk status based on the correlation risk index of adjacent hole pairs through an associated risk unit, and makes differentiated adjustments to the feeding speed curve, clamping force, and punching sequence, thus preventing material deformation risks caused by excessively close hole spacing from a top-level strategy perspective; and it responds to the punching risk status through an inter-hole deformation unit, adjusting the punching feed speed and clamping pressure based on a quantitative assessment of the dynamic impact of punching. The system actively pre-adjusts the force, reducing the dynamic impact and extrusion deformation of the punch on the weak material between holes from the punching execution level. The hole-to-hole orientation compensation unit performs in-situ detection and deformation type identification of the hole center distance deviation and hole edge protrusion after punching, and provides directional auxiliary compensation for punching speed and pressure, achieving closed-loop control of single-hole quality from the feedback correction level. The negative feedback unit adjusts the threshold range of the associated risk index based on batch deformation indicators, dynamically optimizing the risk judgment criteria according to actual working conditions. Punching is completed while ensuring no deformation of the material between holes, significantly reducing the scrap rate caused by excessively close hole spacing and improving the processing accuracy and automation level of the device.

[0016] Furthermore, this invention calculates the reference values ​​of the net cross-sectional width between holes and the material's resistance to deformation by detecting the material type, leg thickness, hole diameter, and hole spacing of the angle steel. This determines the associated risk index, and based on a comparison of the associated risk index with a preset threshold range, the processed hole pairs are divided into a first punching risk state, a second punching risk state, and a third punching risk state. Differentiated control strategies are adopted for different risk states. For the second punching risk state, the feed speed curve deceleration distance is increased to reduce the uniform speed, and the clamping force is enhanced and adjusted to reduce the impact of feed inertia on the weak material between holes, suppressing local material warping during punching. For the third punching risk state, the continuous punching sequence is reorganized into a skip sequence of punching odd-numbered holes first and then punching even-numbered holes, avoiding impact superposition from the processing order and preventing material tearing and hole shape distortion between adjacent holes. This achieves the identification and adaptive adjustment of process risks caused by excessively close hole spacing or excessively large hole diameters, ensuring punching quality while maintaining processing efficiency, and significantly reducing the scrap rate caused by material deformation between holes.

[0017] Furthermore, under the second punching risk state, this invention determines the extrusion influence range coefficient and the punch dynamic impact coefficient, and then synthesizes the punching dynamic impact amount, thereby achieving a comprehensive quantitative assessment of the geometric extrusion effect and dynamic inertial impact effect in a single punching operation. Based on the comparison between the punching dynamic impact amount and the first and second impact thresholds, the punching dynamic risk is classified into levels, and differentiated adjustment measures are taken for each level. Based on the quantitative prediction and graded adjustment method of the actual structural parameters of the punch and the weakness of the current processing object, the dynamic impact and extrusion deformation of the weak material between the holes at the moment of punch contact are effectively reduced, while avoiding excessive sacrifice of processing cycle under unnecessary circumstances, thus achieving precise and proactive control of the punching quality of medium-risk holes.

[0018] Furthermore, after punching is completed under the second punching risk state, the present invention obtains the center-to-center distance deviation between the two holes through a contact displacement sensor, and simultaneously measures the amount of protrusion of the material on the outer edge of the hole relative to the reference surface through the displacement sensor. The center-to-center distance deviation and the amount of protrusion at the hole edge are compared with preset thresholds to automatically identify tensile deformation of the material between holes, extrusion deformation of the material at the hole edge, or a combination of both. Differentiated parameter compensation strategies are adopted for different types. For tensile deformation, the punching feed speed is reduced first and the punching pressure is reduced as an auxiliary measure. For extrusion deformation, the punching pressure is reduced first and the punching speed is reduced as an auxiliary measure. For combination deformation, the pressure is compensated first and the speed is reduced in a combined manner. This realizes the identification of deformation type after punching and the directional closed-loop compensation of punching parameters, ensuring that the processing quality of subsequent holes with similar risk gradually converges to the allowable tolerance range.

[0019] Furthermore, after completing a batch of angle steel punching, this invention determines the batch deformation index by statistically analyzing the average deviation and average protrusion of all holes in the second risk state, thus achieving a comprehensive quantitative evaluation of the processing quality of risk holes in the entire batch. The batch deformation index is compared with a preset quality target threshold. When the batch deformation index exceeds the quality target threshold, it is determined that the current risk index threshold range is set too loosely. The upper limit of the risk index threshold range is then increased based on the product of the deviation and the batch adjustment coefficient, allowing more holes to be included in the compensation control range of the second punching risk state. Based on the batch-level quality statistical data, the threshold adaptive adjustment mechanism enables the risk judgment standard to be automatically corrected according to actual production conditions, mold wear status, and material batch differences. This avoids the problems of missed judgments or excessive intervention that occur under different working conditions with fixed thresholds, achieving a complete closed loop of punching quality control from single-hole compensation to batch self-learning. Attached Figure Description

[0020] Figure 1 This is a side view of the punching mechanism in an embodiment of the present invention; Figure 2 This is a side view of the feeding mechanism in an embodiment of the present invention; Figure 3 This is a simplified side view of the feeding mechanism in an embodiment of the present invention; Figure 4 This is a structural diagram of the finished product rack for punching angle steel in an embodiment of the present invention; In the diagram: 1-Punching unit, 2-Marking device, 3-Cutting device, 4-Frame foundation, 5-Feeding rack, 6-Feeding cylinder, 7-Servo motor, 8-Clamping assembly, 11-Punch. Detailed Implementation

[0021] To make the objectives and advantages of the present invention clearer, the present invention will be further described below with reference to embodiments; it should be understood that the specific embodiments described herein are merely for explaining the present invention and are not intended to limit the present invention.

[0022] Preferred embodiments of the present invention will now be described with reference to the accompanying drawings. Those skilled in the art should understand that these embodiments are merely illustrative of the technical principles of the present invention and are not intended to limit the scope of protection of the present invention.

[0023] It should be noted that in the description of this invention, the terms "upper", "lower", "left", "right", "inner", "outer", etc., which indicate directions or positional relationships, are based on the directions or positional relationships shown in the accompanying drawings. This is only for the convenience of description and is not intended to indicate or imply that the device or element must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, it should not be construed as a limitation of this invention.

[0024] Furthermore, it should be noted that, in the description of this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0025] Please see Figures 1-4 As shown, Figure 1 This is a side view of the punching mechanism in an embodiment of the present invention; Figure 2 This is a side view of the feeding mechanism in an embodiment of the present invention; Figure 3 This is a simplified side view of the feeding mechanism in an embodiment of the present invention; Figure 4 This is a structural diagram of the finished product rack for punching angle steel in an embodiment of the present invention.

[0026] This invention provides a punching device for processing angle steel for power transmission towers, comprising: The feeding mechanism, whose base is the feeding frame 5, is used to clamp and fix the angle steel and control the feeding distance of the angle steel; The punching mechanism, whose base is the frame foundation 4, is used to control several punching punches to punch angle steel based on different hole shapes; The associated risk unit is used to determine the punching risk status of angle steel based on the maximum value of the associated risk index of several adjacent hole pairs, and to adjust the feeding speed curve and clamping force of the feeding mechanism and the punching sequence of the punching mechanism. The inter-hole deformation unit is used to respond to the punching risk state, determine the degree of extrusion deformation of the inter-hole material under the current hole pair parameters based on the punching dynamic impact amount, and adjust the punching feed speed and clamping pressure. The hole orientation compensation unit is used to determine the hole deformation type of the current punching risk pair based on the hole center distance deviation and hole edge protrusion, and to determine the auxiliary adjustment method of the actual punching feed speed and actual punching pressure. The negative feedback unit, which is connected to the associated risk unit, is used to adjust the risk index threshold range of the associated risk index based on the batch deformation index.

[0027] In this embodiment, the punching device for angle steel processing includes a feeding mechanism, a punching mechanism, and a finished product rack.

[0028] The feeding mechanism has a feeding frame as its base. The feeding mechanism includes a servo motor 7, a feeding cylinder 6, a clamping assembly 8, and a centering assembly. The servo motor is used to precisely control the feeding distance. Its output end is connected to a linear transmission unit such as a ball screw or a rack and pinion to drive the slide with the clamping assembly to reciprocate along the guide rail. The clamping assembly is driven by the feeding cylinder and is used to clamp the angle steel during the feeding stroke. The centering assembly is set at the punching station and includes centering jaws and displacement sensors symmetrically arranged along the cross-sectional direction of the angle steel. The punching mechanism includes a frame base, and along the direction of travel of the angle steel, a marking device 2, a punching unit 1, and a cutting device 3 are arranged in sequence. The punching unit includes a hydraulic cylinder and a punch mounting seat installed at its output end. At least three punching punches 11 of different models are arranged side by side on the punch mounting seat to adapt to different hole shapes. A proportional relief valve is provided in the oil inlet circuit of the hydraulic cylinder. The marking device is used to mark and imprint the angle steel before punching, and the cutting device is used to cut the angle steel to a fixed length after punching.

[0029] Specifically, this invention achieves precise feeding and positioning of angle steel through the cooperation of a servo motor, clamping components, and centering components in the feeding mechanism; it enables adaptive punching of multiple hole types through at least three different types of punches arranged side-by-side in the punching mechanism and a proportional overflow valve; it determines the punching risk status based on the correlation risk index of adjacent hole pairs through an associated risk unit, and differentiates the feeding speed curve, clamping force, and punching sequence to prevent material deformation risks caused by excessively close hole spacing from a top-level strategy; and it proactively pre-adjusts the punching feed speed and clamping pressure based on a quantitative assessment of the dynamic impact of punching, in response to the punching risk status through an inter-hole deformation unit. This system reduces the dynamic impact and extrusion deformation of the punch on the weak material between holes from the punching execution level. Through the hole-to-hole orientation compensation unit, it performs in-situ detection and deformation type identification of the hole center distance deviation and hole edge protrusion after punching, and provides directional auxiliary compensation for punching speed and pressure, achieving closed-loop control of single-hole quality from the feedback correction level. The negative feedback unit adjusts the threshold range of the associated risk index based on batch deformation indicators, dynamically optimizing the risk judgment criteria according to actual working conditions. By completing the punching process while ensuring that the material between holes does not deform, it significantly reduces the scrap rate caused by excessively close hole spacing, improving the processing accuracy and automation level of the device.

[0030] In this embodiment, during the punching process of angle steel, if the hole spacing of the hole pairs is too close or the hole diameter is too large, it may lead to material deformation and tearing.

[0031] The associated risk index is determined by the sub-unit based on the characteristic parameters of the angle steel to be punched, which determines the net cross-sectional width between the holes to be punched, and then combined with the basic attribute parameters of the angle steel to determine the associated risk index.

[0032] Understandably, the larger the historical aperture, the greater the impact and pulling range on the surrounding material during punching, and the higher the risk; the greater the thickness of the angle steel leg, the greater the energy required for punching and the greater the stress generated, and the higher the risk; the net cross-sectional width between holes is the core structural dimension for resisting deformation, and the larger the value, the lower the risk; the larger the reference value for the material's resistance to deformation, the higher the material strength, the stronger the resistance to deformation, and the lower the risk; the larger the associated risk index, the higher the risk of unexpected deformation, tearing, or increased deviation of the hole center distance in the material between holes when punching at that location.

[0033] The risk status comparison subunit determines the maximum associated risk index value in the entire processing sequence based on the associated risk index of several adjacent hole pairs, and determines the punching risk status of adjacent hole pairs of angle steel based on the comparison result of the maximum associated risk index value and the risk index threshold range.

[0034] Specifically, if the associated risk index is lower than the risk index threshold range, the risk status comparison sub-unit determines that the angle steel is in the first punching risk state. The geometric relationship between the hole spacing and hole diameter, the combination of material strength and thickness of each hole pair in the angle steel processing sequence are within the safe range. There is sufficient material strength between the holes to absorb the punching impact and no deformation affecting the quality will occur. If the associated risk index is within the risk index threshold range, the risk status comparison sub-unit determines that the angle steel is in the second punching risk state. There is a risk of slight deformation of the geometry and material combination of the hole pairs in the angle steel processing sequence. Direct continuous punching may result in hole center offset or local material protrusion. Effective compensation and control can be achieved by adjusting the process parameters in real time during the punching process. If the associated risk index is higher than the risk index threshold range, the risk status comparison sub-unit determines that the angle steel is in the third punching risk state. There are extremely high risk hole pairs in the angle steel processing sequence, such as extreme combinations of large hole diameter, thick plate, small hole spacing, and low strength material. If punching is carried out directly and continuously at this time, there is a risk of material tearing between adjacent holes and severe hole shape distortion. The impact superposition should be avoided from the processing sequence.

[0035] In this embodiment, the angle steel parameter subunit obtains the basic attribute parameters of the angle steel, including the material type, the angle steel leg width, and the angle steel leg thickness. In practice, the material type is obtained by reading the material grade, such as Q235, Q355, and Q420. The material type is used to query the corresponding material mechanical property values. The leg width is the width of a single leg of the angle steel, in millimeters (mm), and the leg thickness is the thickness of a single leg of the angle steel, in millimeters (mm).

[0036] The angle steel parameter subunit acquires the characteristic parameters of the holes to be punched on the angle steel, including the hole diameter and hole spacing. In practice, for each hole to be punched on the angle steel, the characteristic parameters of the holes to be punched are acquired according to their distribution order along the length of the angle steel. The hole diameter is the diameter of the current hole, in millimeters (mm), and the hole spacing is the design distance between the current hole and the center of the previous hole adjacent to it along the length of the angle steel, in millimeters (mm). For the first hole, its hole spacing can be defined as the distance from the end of the angle steel to the center of the hole.

[0037] The associated risk index is determined based on the ratio of the characteristic value of aperture limb thickness to the characteristic value of hole spacing deformation resistance. The characteristic value of aperture limb thickness is determined based on the product of historical aperture and angle steel limb thickness. The characteristic value of hole spacing deformation resistance is determined based on the product of the net cross-sectional width between holes and the reference value of the material's deformation resistance.

[0038] In this embodiment, the punching risk adjustment subunit adjusts the punching strategy of the angle steel based on the punching risk status of the angle steel.

[0039] The punching risk adjustment subunit adjusts the feeding speed curve and clamping force based on the angle steel being in the second punching risk state. Specifically, the punching risk adjustment subunit advances the starting point of the deceleration segment of the feeding speed curve, increases the deceleration distance to 1.5 times the standard value, and reduces the switching speed from the constant speed segment to the deceleration segment, reducing the constant speed to 70% of the standard value. The feeding mechanism will begin to approach slowly and smoothly when it is far from the target hole position, so as to minimize the impact of feeding inertia on the weak material area between the holes. By controlling the pneumatic or hydraulic proportional valve of the feeding fixture, the clamping pressure is increased by 10%-20% on the basis of the standard value to provide stronger material constraint and suppress the local material warping that may occur during punching.

[0040] The punching risk adjustment subunit adjusts the punching sequence of the angle steel based on the angle steel being in the third punching risk state. The original continuous hole sequence table is reorganized into a skip sequence that punches odd-numbered holes first and then punches even-numbered holes back, according to the position of the risk hole pairs.

[0041] In this embodiment, for each group of adjacent holes, the angle steel parameter sub-unit determines the minimum material width between the hole edges, i.e., the net cross-sectional width between holes, which is determined based on the difference between the hole center distance and the historical hole diameter. In practice, the hole center distance is the hole spacing between the current hole and the previous hole, and the historical hole diameter is the hole diameter of the previous hole.

[0042] It is understandable that the net cross-sectional width between holes directly represents the width of the solid material between two adjacent holes that has not been cut and has withstood the impact force of punching and residual stress. The smaller the net cross-sectional width between holes, the thinner the material.

[0043] The angle steel parameter subunit directly queries the reference value of the material's deformation resistance corresponding to the material's deformation resistance from the process parameter comparison table based on the material type; In this embodiment, material type Q235 corresponds to a yield strength (MPa) ≥ 235 and a material deformation resistance reference value of 1.0; material type Q355 corresponds to a yield strength (MPa) ≥ 355 and a material deformation resistance reference value of 1.47; material type Q420 corresponds to a yield strength (MPa) ≥ 420 and a material deformation resistance reference value of 1.79. It is understandable that the reference value for material deformation resistance represents the relative deformation resistance of different materials in punching. Taking the most common Q235 as the base value of 1.0, the reference value for the material deformation resistance of other materials is preset according to the approximate proportional relationship of their yield strength. For example, the yield strength of Q355 is about 1.47 times that of Q235, so its material deformation resistance reference value is set to 1.47. It directly reflects the relative ability of the material to resist plastic deformation. The larger the material deformation resistance reference value, the less likely punching deformation will occur.

[0044] The risk index threshold range is implemented as two to four, and the values ​​are based on statistical data of punching process tests on commonly used power tower angle steel materials of Q235, Q355, and Q420 under different thicknesses, hole diameters, and hole spacing combinations. When the associated risk index is less than two, the combination of the net cross-sectional width between holes and the material's resistance to deformation is in a safe range, and the hole center distance deviation and hole edge protrusion after punching are stable within the allowable tolerance range of the process specifications, requiring no additional intervention. When the associated risk index reaches or exceeds two, the net cross-sectional width between holes is insufficient to fully absorb the punching impact, and detectable micro-deformation begins to appear after punching, requiring compensation control through adjustment of the feeding speed curve and enhancement of clamping force. When the associated risk index exceeds four, the material between holes is in a critical unstable state, and even with parameter compensation, it is difficult to reliably guarantee quality. It is necessary to avoid stress superposition by skipping punching steps in the processing sequence.

[0045] Specifically, this invention detects the material type, leg thickness, hole diameter, and hole spacing of the angle steel to calculate the reference value of the net cross-sectional width between holes and the material's resistance to deformation. This determines the associated risk index, and based on a comparison of the associated risk index with a preset threshold range, the processed hole pairs are divided into three risk states: a first, a second, and a third. Differentiated control strategies are adopted for each risk state. For the second risk state, the feed speed curve's deceleration distance is increased to reduce the uniform speed, and the clamping force is enhanced to reduce the impact of feeding inertia on the weak material between holes, suppressing local material warping during punching. For the third risk state, the continuous punching sequence is reorganized into a skip sequence of punching odd-numbered holes first and then returning to punch even-numbered holes, avoiding impact superposition in the processing order and preventing material tearing and hole shape distortion between adjacent holes. This achieves the identification and adaptive adjustment of process risks caused by excessively close hole spacing or excessively large hole diameters, ensuring punching quality while maintaining processing efficiency, and significantly reducing the scrap rate caused by material deformation between holes.

[0046] In this embodiment, the three punches correspond to three nominal hole diameter ranges. Although they work independently, the structural differences between the punches will affect the force transmission characteristics during punching. Based on the fact that the angle steel is in the second punching risk state, the dynamic response characteristics during punching are analyzed in advance according to the punch specifications matched with the current risk hole position, and the punching parameters that are most conducive to protecting the material between the holes are set accordingly.

[0047] The impact determination subunit obtains the execution punch corresponding to the diameter of the current risk hole position, and determines the cross-sectional area of ​​the execution punch and the mass of each punch; The impact determination subunit determines the extrusion influence range coefficient based on the ratio of the punch cross-sectional area of ​​the executing punch to the net cross-sectional width between the holes of the current risk hole pair; The impact determination subunit determines the dynamic impact coefficient of the punch based on the product of the total mass of the three punches and the punching feed speed set by the punching punch. The punching feed speed is in m / s. The impact determination sub-unit determines the dynamic impact of punching based on the product of the extrusion influence range coefficient and the dynamic impact coefficient of the punch, with the unit being kg·m² / s.

[0048] Understandably, the cross-sectional area of ​​the punch determines the magnitude of the punching force and the range of extrusion influence. The total mass of the punch is the total mass of the entire punch assembly, affecting the inertial force during punching. The larger the punch area, the larger the extrusion influence zone on the material around the hole during punching. The smaller the net cross-sectional width between holes, the easier it is for the influence zone to cover the entire weak area between holes. The larger the extrusion influence range coefficient value, the higher the extrusion risk. The greater the momentum of the punch assembly at the moment of contact with the angle steel, the stronger the initial impact on the material between holes. Since the three punches are mounted together on the punch mounting base, even if only one punch is performing work, the mass of the remaining punches will increase the overall inertia, thereby increasing the impact at the moment of contact. The larger the dynamic impact coefficient value of the punch, the higher the dynamic impact risk. The punching dynamic impact quantity integrates the geometric characteristics, dynamic characteristics of the punch, and the weakness of the current workpiece. The larger the punching dynamic impact quantity value, the higher the overall risk of extrusion deformation of the weak material between holes when punching with this punch under the current risk state.

[0049] If the dynamic impact of punching is less than the first impact threshold, the inter-hole deformation comparison sub-unit determines that the dynamic impact and squeezing effect of the punching process are within a controllable range. If the dynamic impact of punching is greater than or equal to the first impact threshold and less than the second impact threshold, the hole deformation comparison sub-unit determines that the punch area or total moving mass poses a risk of extrusion deformation to the current hole material, and adjusts the dynamic impact to prevent this. If the dynamic impact of punching is greater than or equal to the second impact threshold, the hole deformation comparison sub-unit determines the total punching motion inertia of the current hole pair for the net cross-sectional width between holes, which causes material deformation between holes.

[0050] In this embodiment, the hole deformation adjustment subunit, based on the risk of extrusion deformation during punching, reduces the punching feed speed by 20% from the current default value through the proportional speed control valve of the hydraulic system, thereby reducing the dynamic impact coefficient of the punch and lowering the dynamic impact of punching; and increases the clamping pressure by 15% from the standard value through the pneumatic / hydraulic proportional valve of the feeding clamping mechanism to enhance the axial constraint stiffness of the material between holes and resist possible slippage.

[0051] The hole deformation adjustment subunit reduces the punching feed speed by 40% from the default value based on the material deformation caused by punching, thereby significantly reducing dynamic impact; and increases the clamping pressure to 90% of the maximum allowable value of the equipment to provide material constraint.

[0052] In this example, the first impact threshold is 50, and the second impact threshold is 120, with the same unit as the dynamic impact of punching. The impact threshold is determined based on the actual structural parameters of the three punches of the punching device under standard working conditions and the process test data of Q235 and Q355 angle steel under different net cross-sectional widths between holes. When the dynamic impact of punching is less than 50, it corresponds to the case where the punch is a small-sized punch and the net cross-sectional width between holes is sufficient. After punching, the measured deviation of the hole center distance and the amount of hole edge protrusion are within the tolerance range. When the dynamic impact of punching reaches 50, it corresponds to the case where the punch is a medium-sized punch with a small net cross-sectional width between holes. After punching, slight deformation begins to appear, requiring preventive intervention. When the dynamic impact of punching reaches 120, it corresponds to the case where the punch is a large-sized punch with a very small net cross-sectional width between holes, and the inertial impact formed by the total mass of the three punches is significantly increased. In this case, the speed reduction range must be increased and the clamping force must be increased to a value close to the maximum allowable value of the equipment in order to effectively control the deformation of the material between holes.

[0053] Specifically, under the second punching risk state, this invention determines the extrusion influence range coefficient and the punch dynamic impact coefficient, and then synthesizes the punching dynamic impact amount to achieve a comprehensive quantitative assessment of the geometric extrusion effect and dynamic inertial impact effect in a single punching operation. Based on the comparison between the punching dynamic impact amount and the first and second impact thresholds, the punching dynamic risk is classified into levels, and differentiated adjustment measures are taken for each level. Based on the quantitative prediction and graded adjustment method of the actual structural parameters of the punch and the weakness of the current processing object, the dynamic impact and extrusion deformation of the weak material between the holes at the moment of punch contact are effectively reduced, while avoiding excessive sacrifice of processing cycle under unnecessary circumstances, and realizing precise and proactive control of the punching quality of medium-risk holes.

[0054] After the punching of the risk holes is completed, the hole orientation compensation unit determines the most realistic deformation state of the angle steel material after punching without subsequent conveying disturbance.

[0055] The offset direction determination subunit determines the actual center distance between two holes based on the sum of the sensor installation spacing and the hole displacement difference, wherein the hole displacement difference is the difference between the current hole displacement and the historical hole displacement.

[0056] The hole edge protrusion determination subunit determines the hole edge protrusion amount based on the difference between the hole edge height value and the reference surface height, with the unit being millimeters (mm). The hole edge protrusion amount reflects the degree of local protrusion formed at the hole edge due to material being extruded during the punching process.

[0057] The inter-hole comparison sub-unit compares the hole center deviation threshold and the hole edge protrusion threshold based on the hole center distance deviation and the hole edge material protrusion. If the absolute value of the hole center distance deviation is less than or equal to the hole center deviation threshold, and the amount of material protrusion at the hole edge is less than or equal to the hole edge protrusion threshold, the inter-hole comparison sub-unit determines that the current punching risk is acceptable for quality. If the absolute value of the hole center distance deviation is greater than the hole center deviation threshold, or the amount of protrusion of the hole edge material is greater than the hole edge protrusion threshold, the hole comparison sub-unit determines that the current punching risk pair is of unqualified quality and determines the hole deformation type of the current punching risk pair.

[0058] Specifically, the hole comparison sub-unit is determined to be a hole material tensile deformation type based on the absolute value of the hole center distance deviation being greater than the hole center deviation threshold and the amount of hole edge material protrusion being less than or equal to the hole edge protrusion threshold. The relevant process parameters for tensile deformation of the material between holes are the peak punching pressure and the punching feed speed. The higher the pressure and the faster the speed, the greater the lateral extrusion force of the punch on the material around the hole, and the more severe the tensile deformation of the material between holes.

[0059] It is understandable that the net cross-sectional width between the current hole and the previous hole is small, and the material has insufficient stiffness in this narrow area. When the punch moves downward to punch, the lateral extrusion force of the punch on the material around the hole pushes the material between the holes to undergo a small amount of plastic tensile flow towards the previous hole. Since the previous hole has already broken the material, the resistance to the lateral thrust is almost zero. Therefore, the actual position of the current hole has shifted away from the previous hole, which is manifested as an increase in the hole center distance. This shift is the result of the local plastic flow of the punched material, not the slippage of the angle steel as a whole in the fixture.

[0060] The inter-hole comparison sub-unit is determined to be an extrusion deformation of the hole edge material based on the absolute value of the hole center distance deviation being less than or equal to the hole center deviation threshold and the amount of protrusion of the hole edge material being greater than the hole edge protrusion threshold. The relevant process parameters for the extrusion deformation of the material at the hole edge are the peak punching pressure and the gap between the punch and the die. With a fixed die gap, the greater the pressure, the more obvious the extrusion effect.

[0061] It is understandable that when the punch moves downward, the compressive stress applied to the material by the punch end is too great, and the material reaches a yield state in a narrow area near the punch cutting edge. Since the material volume is incompressible, the compressed material will flow in the direction of least resistance. The downward flow forms scrap that is pushed out, the lateral flow is constrained by the die, and the upward flow manifests as the formation of annular protrusions on the surface of the angle steel at the edge of the hole.

[0062] The hole deformation compensation subunit determines the blanking feed speed adjustment amount based on the tensile deformation of the material between holes, adjusts the actual blanking feed speed, and correspondingly assists in adjusting the actual blanking pressure. In practice, the hole deformation compensation subunit determines the blanking feed speed adjustment amount based on the absolute value of the hole center distance deviation and the speed compensation coefficient. The blanking feed speed adjustment amount is determined by the product of the difference between the absolute value of the hole center distance deviation and the hole center deviation threshold and the negative speed compensation coefficient. The hole deformation compensation sub-unit reduces the punching pressure based on the ratio of the absolute value of the hole center distance deviation to the hole center deviation threshold.

[0063] In this embodiment, the speed compensation coefficient is in units of (mm / s) / mm, which is an empirical constant set according to the material type of the angle steel. For example, for Q235 material, the speed compensation coefficient is preset to five, that is, for every 0.01 mm deviation of the hole center distance from the hole center deviation threshold, the punching speed is reduced by 0.05 mm per second.

[0064] Understandably, reducing the punching speed allows the material more time to release stress and deform evenly under the extrusion of the punch, reducing the instantaneous peak value of the lateral thrust on the punch, thereby mitigating the lateral extrusion and stretching effect on the material between holes; and by reducing the punching pressure, the amplitude of the lateral extrusion force of the punch on the material around the hole can be directly reduced.

[0065] The hole deformation compensation subunit determines the punching pressure adjustment amount based on the extrusion deformation of the material at the hole edge, adjusts the actual punching pressure, and correspondingly assists in adjusting the actual punching feed speed. In practice, the hole deformation compensation subunit determines the punching pressure adjustment amount based on the amount of material protrusion at the hole edge, the hole edge protrusion threshold, and the pressure compensation coefficient. The punching pressure adjustment amount is determined by multiplying the difference between the material protrusion at the hole edge and the hole edge protrusion threshold with a negative pressure compensation coefficient.

[0066] The hole deformation compensation sub-unit reduces the punching feed speed based on the difference between the material protrusion at the hole edge and the hole edge protrusion threshold.

[0067] In this embodiment, the pressure compensation coefficient is in MPa / mm, which is an empirical constant set according to the material type of the angle steel. For example, for Q235 material, the pressure compensation coefficient is preset to two, that is, for every 0.01 mm of protrusion exceeding the hole edge protrusion threshold, the punching pressure is reduced by 0.02 MPa.

[0068] It is understandable that punching pressure is the direct cause of material extrusion. Reducing the pressure to a level that ensures fracture separation can minimize the upward extrusion flow of the material. When the pressure has been reduced to the lower limit but the bulge has not yet reached the target, reducing the punching speed can reduce the material strain rate, allowing the material more time to complete fracture separation in a smoother manner, thus indirectly reducing extrusion.

[0069] In this embodiment, on the output side of the angle steel at the punching station, two contact displacement sensors are provided along the length of the angle steel, namely a front-end sensor and a rear-end sensor. The installation spacing of the sensors along the length of the angle steel is a fixed spacing. The sensors adopt a telescopic ejector pin structure, and the front end of the ejector pin is conical, which can fall into the punched hole to achieve mechanical positioning.

[0070] After the current hole is punched, the feeding mechanism will transport the angle steel forward, so that the previous hole is moved directly below the rear sensor, and the current hole is directly below the front sensor. It can be understood that the forward transport position of the angle steel is calculated and determined based on the design center distance of the two holes and the sensor installation spacing.

[0071] The pins of the two displacement sensors descend simultaneously and fall into the two holes respectively. The conical front end of the pin automatically centers to ensure that the pin axis coincides with the center of the hole. The displacement sensors read the displacement value of their respective pins in the length direction of the angle steel. The front sensor reading is the current hole displacement, and the rear sensor reading is the historical hole displacement.

[0072] The offset direction determination sub-unit determines the hole center distance deviation based on the difference between the actual hole center distance and the designed hole center distance. If the hole center distance deviation is greater than zero and the actual hole center distance is greater than the designed hole center distance, it means that the current hole is offset outward relative to the previous hole. If the hole center distance deviation is less than zero and the actual hole center distance is less than the designed hole center distance, it means that the current hole is offset inward relative to the previous hole.

[0073] The hole edge protrusion determination sub-unit contact measurement uses a push rod type displacement sensor fixed next to the punching die to detect the local protrusion height of the material at the hole edge; In this embodiment, a contact displacement sensor is installed on the side of the punching die. The sensor probe is a flat disc with a diameter of about 3mm. The sensor is installed 1mm outside the edge of the hole after punching. The sensor is fixed on the frame and does not move with the punching die.

[0074] During implementation, after punching is completed, the probe of the displacement sensor is driven by a cylinder to press down, contacting the surface of the angle steel outside the hole edge with a constant small pressure of about 0.5N. The sensor reads the hole edge height value h1 at the current position. To obtain a reference benchmark, on the same angle steel, in an unpunched area at least three times the hole diameter upstream of the current punching position, the sensor is also used to measure the reference surface height h0. The reference surface height h0 can be completed after the first angle steel of this batch is fed into place but before punching begins.

[0075] In this embodiment, the actual peak pressure during the punching stroke is extracted from the hydraulic system pressure sensor data record, with the unit being megapascals (MPa). The extraction range is the time period from when the punch contacts the material to when the material breaks apart. The actual punching feed rate is also extracted, with the unit being millimeters per second (mm / s). The actual punching feed rate is the average speed during the period from when the punch contacts the material to when it breaks apart.

[0076] In this embodiment, the hole comparison sub-unit determines the hole deformation type as a composite deformation based on the absolute value of the hole center distance deviation being greater than the hole center deviation threshold and the amount of hole edge material protrusion being greater than the hole edge protrusion threshold.

[0077] The inter-hole comparison sub-unit is based on composite deformation. It first solves the problem of material extrusion at the hole edge by performing punching pressure compensation, and then solves the problem of material stretching between holes by punching speed compensation.

[0078] The implementation example of the hole center deviation threshold and the hole edge protrusion threshold is 0.1 mm. The value is based on the general requirements for hole center distance tolerance and surface quality in the punching process specification of angle steel for power transmission towers. This value can effectively distinguish between normal process fluctuations and abnormal deformation caused by excessively close hole spacing. The values ​​of the speed compensation coefficient and the pressure compensation coefficient are based on the deformation calibration test data of Q235 angle steel under different punching speeds and pressures. When the hole center distance deviation exceeds 0.1 mm, compensation is performed at a rate of decreasing the punching speed by 0.05 mm / s for every 0.01 mm deviation. After about three to five iterations at different hole positions, the deviation can converge to within the threshold. When the hole edge protrusion exceeds 0.1 mm, compensation is performed at a rate of decreasing the punching pressure by 0.02 MPa for every 0.01 mm deviation. This can gradually eliminate the protrusion without causing the material to be unable to break and separate. This set of coefficients can be converted accordingly for other materials based on their yield strength ratio.

[0079] Specifically, after punching is completed under the second punching risk state, the present invention obtains the center-to-center deviation of the two holes through a contact displacement sensor, and simultaneously measures the amount of protrusion of the material on the outer edge of the hole relative to the reference surface through the displacement sensor. The center-to-center deviation and the amount of protrusion at the hole edge are compared with preset thresholds to automatically identify tensile deformation of the material between holes, extrusion deformation of the material at the hole edge, or a combination of both. Differentiated parameter compensation strategies are adopted for different types. For tensile deformation, the punching feed speed is reduced first and the punching pressure is reduced as an auxiliary measure. For extrusion deformation, the punching pressure is reduced first and the punching speed is reduced as an auxiliary measure. For combined deformation, the pressure is compensated first and then the speed. This realizes the identification of deformation type after punching and the directional closed-loop compensation of punching parameters, ensuring that the processing quality of subsequent holes with similar risks gradually converges to the allowable tolerance range.

[0080] In this embodiment, the deformation index determination subunit determines the average deviation and average protrusion based on the average value of the hole center distance deviation and the average value of the hole edge protrusion of several second risk state hole positions. The deformation index determination sub-unit determines the batch deformation index based on the sum of the average deviation and the average protrusion, with the unit being millimeters, which comprehensively reflects the overall deformation degree of the risky holes in this batch.

[0081] The deformation index comparison subunit is based on the batch deformation index comparison quality target threshold. If the batch deformation index is greater than the quality target threshold, the deformation index comparison subunit determines the risk index threshold range to be too loose. The current risk threshold fails to include the hole pairs with deformation exceeding the tolerance within the compensation control range. The negative feedback adjustment subunit increases the upper limit of the risk index threshold range based on the product of the difference between the batch deformation index and the quality target threshold and the batch adjustment coefficient. In this embodiment, the batch adjustment coefficient is used to adjust the upper limit of the risk index threshold range by 0.5 for every 0.01 mm deviation of the batch comprehensive deformation from the target. The value is based on the statistical analysis of punching test data of multiple batches of Q235 and Q355 angle steel at different die wear stages. When the batch deformation index exceeds the target threshold by 0.01 mm, the upper limit of the risk index threshold is increased by 0.5. After about three to five batches of iteration, the batch deformation index can converge to near the target threshold. The quality target threshold is implemented as 0.1 mm, and the value is based on the allowable tolerance requirements for hole center distance deviation and surface protrusion in the punching process specification of power tower angle steel. It is consistent with the hole center deviation threshold and hole edge protrusion threshold to ensure that the batch-level quality evaluation and single-hole-level quality judgment adopt a unified accuracy standard. Specifically, after completing a batch of angle steel punching, this invention determines the batch deformation index by statistically analyzing the average deviation and average protrusion of all holes in the second risk state, thus achieving a comprehensive quantitative evaluation of the processing quality of risk holes in the entire batch. The batch deformation index is compared with a preset quality target threshold. When the batch deformation index exceeds the quality target threshold, it is determined that the current risk index threshold range is set too loosely. The upper limit of the risk index threshold range is then increased based on the product of the deviation and the batch adjustment coefficient, allowing more holes to be included in the compensation control range for the second punching risk state. Based on a batch-level quality statistical data-driven threshold adaptive adjustment mechanism, the risk judgment standard can be automatically corrected according to actual production conditions, mold wear, and material batch differences, avoiding the problems of missed judgments or excessive intervention that occur under different working conditions with fixed thresholds. This achieves a complete closed loop for punching quality control, from single-hole compensation to batch self-learning.

[0082] The technical solution of the present invention has been described above with reference to the preferred embodiments shown in the accompanying drawings. However, it will be readily understood by those skilled in the art that the scope of protection of the present invention is obviously not limited to these specific embodiments. Without departing from the principles of the present invention, those skilled in the art can make equivalent changes or substitutions to the relevant technical features, and the technical solutions after these changes or substitutions will all fall within the scope of protection of the present invention.

Claims

1. A punching device for processing angle steel for power transmission towers, characterized in that, include: The feeding mechanism, whose base is a feeding frame, is used to clamp and fix the angle steel and control the feeding distance of the angle steel; The punching mechanism, whose base is a frame foundation, is used to control several punching punches to punch angle steel based on different hole shapes; The associated risk unit is used to determine the punching risk status of angle steel based on the maximum value of the associated risk index of several adjacent hole pairs, and to adjust the feeding speed curve and clamping force of the feeding mechanism and the punching sequence of the punching mechanism. The inter-hole deformation unit is used to respond to the punching risk state, determine the degree of extrusion deformation of the inter-hole material under the current hole pair parameters based on the punching dynamic impact amount, and adjust the punching feed speed and clamping pressure. The hole orientation compensation unit is used to determine the hole deformation type of the current punching risk pair based on the hole center distance deviation and hole edge protrusion, and to determine the auxiliary adjustment method of the actual punching feed speed and actual punching pressure. The negative feedback unit, which is connected to the associated risk unit, is used to adjust the risk index threshold range of the associated risk index based on the batch deformation index.

2. The punching device for processing angle steel for power transmission towers according to claim 1, characterized in that, The punching mechanism is equipped with a marking device, a punching unit, and a cutting device along the angle steel feeding direction; The punch mounting base at the output end of the punching unit is equipped with several punching punches arranged side by side to accommodate different hole shapes. The cutting device is used to cut the angle steel to a fixed length after punching. The marking device is used to mark and stamp the angle steel before punching.

3. The punching device for processing angle steel for power transmission towers according to claim 1, characterized in that, The associated risk unit includes: Angle steel parameter subunit is used to obtain the basic attribute parameters and punching characteristic parameters of the angle steel. The basic attribute parameters include material type, angle steel leg width and angle steel leg thickness, and the punching characteristic parameters include hole diameter and hole spacing. The associated risk index determination sub-unit is used to determine the net cross-sectional width between holes of the current hole to be punched based on the characteristic parameters of the hole to be punched in the angle steel, and to determine the associated risk index in combination with the basic attribute parameters of the angle steel. The risk status comparison subunit is used to determine the punching risk status of adjacent hole pairs of angle steel based on the comparison results between the maximum associated risk index value and the risk index threshold range. The punching risk adjustment subunit is used to adjust the feeding speed curve, clamping force, and angle steel punching sequence based on the punching risk status.

4. The punching device for processing angle steel for power transmission towers according to claim 3, characterized in that, Based on the fact that the associated risk index is below the risk index threshold range, the risk status comparison sub-unit determines that the angle steel is in the first punching risk state. Based on the correlation risk index being within the risk index threshold range, the risk status comparison subunit determines that the angle steel is in the second punching risk state. There is a risk of hole-to-punch deformation in the angle steel processing sequence. The punching risk adjustment subunit adjusts the feeding speed curve and clamping force. Based on the correlation risk index being higher than the risk index threshold range, the risk status comparison subunit determines that the angle steel is in the third punching risk state, and the punching risk adjustment subunit adjusts the punching sequence of the angle steel.

5. The punching device for processing angle steel for power transmission towers according to claim 1, characterized in that, The inter-hole deformation unit includes: The impact determination subunit is used to determine the dynamic impact amount of punching based on the product of the extrusion influence range coefficient and the punch dynamic impact coefficient. The inter-hole deformation comparison sub-unit is used to determine whether the material between holes is at risk of extrusion deformation or to predict the deformation of the material between holes caused by punching, based on the comparison results of the dynamic impact amount and impact threshold of punching. The hole deformation adjustment subunit is used to determine the extent to decrease the punching feed speed and increase the clamping pressure based on the risk of extrusion deformation during punching or the deformation of the material between the holes caused by punching.

6. The punching device for processing angle steel for power transmission towers according to claim 5, characterized in that, The impact determination subunit determines the extrusion influence range coefficient based on the ratio of the punch cross-sectional area of ​​the executing punch to the net cross-sectional width between the holes of the current risk hole pair; The impact determination subunit determines the dynamic impact coefficient of the punch based on the product of the total mass of the punch and the punching feed speed; The inter-hole deformation comparison sub-unit determines that the punch area or total moving mass poses a risk of extrusion deformation to the current inter-hole material based on the dynamic impact of punching being greater than or equal to the first impact threshold and less than the second impact threshold. The inter-hole deformation comparison sub-unit is based on the dynamic impact of punching being greater than or equal to the second impact threshold. It determines the total punching motion inertia of the current hole pair for the material deformation caused by punching the net cross-sectional width between the holes.

7. The punching device for processing angle steel for power transmission towers according to claim 1, characterized in that, The inter-hole orientation compensation unit includes: The offset direction determination sub-unit is used to determine the actual hole center distance between two holes based on the installation spacing and hole displacement difference, and to determine the hole center distance deviation based on the actual hole center distance and the designed hole center distance. The hole edge protrusion determination sub-unit is used to determine the amount of hole edge protrusion based on the hole edge height value and the reference surface height; The inter-hole comparison sub-unit is used to determine the inter-hole deformation type of the current punching risk pair based on the comparison results of the hole center distance deviation and hole edge material protrusion with the hole center deviation threshold and hole edge protrusion threshold. The hole deformation compensation subunit is used to determine the adjustment amount of the actual punching feed speed or the actual punching pressure based on the type of hole deformation, and to assist in adjusting the actual punching pressure or the actual punching feed speed.

8. The punching device for processing angle steel for power transmission towers according to claim 7, characterized in that, The offset direction determination subunit locates the current hole offset direction based on the actual hole center distance and the magnitude of the hole center distance deviation, wherein the hole displacement difference is the difference between the current hole displacement and the historical hole displacement. The hole-to-hole comparison sub-unit is determined to be a tensile deformation of the hole material based on the absolute value of the hole center distance deviation being greater than the hole center deviation threshold and the amount of material protrusion at the hole edge being less than or equal to the hole edge protrusion threshold. The inter-hole comparison sub-unit is determined to be an extrusion deformation of the hole edge material based on the absolute value of the hole center distance deviation being less than or equal to the hole center deviation threshold and the amount of protrusion of the hole edge material being greater than the hole edge protrusion threshold.

9. The punching device for processing angle steel for power transmission towers according to claim 8, characterized in that, The hole deformation compensation subunit determines the blanking feed speed adjustment amount based on the tensile deformation of the material between holes, adjusts the actual blanking feed speed, and correspondingly assists in adjusting the actual blanking pressure. The hole deformation compensation subunit determines the punching pressure adjustment amount based on the extrusion deformation of the material at the hole edge, adjusts the actual punching pressure, and correspondingly assists in adjusting the actual punching feed speed.

10. The punching device for processing angle steel for power transmission towers according to claim 1, characterized in that, The negative feedback unit includes: The deformation index determination subunit is used to determine the batch deformation index based on the average deviation and average protrusion of several second-risk state holes. The deformation index comparison subunit is used to determine the risk index threshold range based on the comparison results of batch deformation indices exceeding the quality target threshold. The negative feedback adjustment subunit is used to increase the upper limit of the risk index threshold range based on the fact that the risk index threshold range is too wide.

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