A forging process for air spring sealing cover

Abstract

The present invention relates to the field of plastic forging, and in particular to a forging process for an air spring sealing cover. The present invention identifies the concave-convex features of each forging die by calling forging die data corresponding to a number of sealing covers and surface data of a blank stored in a sample database; determines stress uniform interference characterization parameters during the forging process of the corresponding sealing cover according to the concave-convex features of each forging die, so as to cluster the forging dies; heats the blank, obtains the surface features of the heated blank, so as to determine whether to pretreat the blank; controls a shearing tool to perform a blank feeding operation, and adaptively forges the sealing cover according to the clustering result; and cools the forged sealing cover. The present invention can reduce the risk of blank folding during the forging process, reduce forging defects caused by stress problems, and improve the forging efficiency of the sealing cover.

Description

Technical Field

[0001] The invention relates to the field of plastic forging, and in particular to a forging process for an air spring sealing cover. Background Art

[0002] The forging of automotive air spring sealing covers mainly adopts the traditional die forging process, which includes placing the heated metal blank into the mold cavity, applying pressure through a press, causing the metal blank to undergo plastic deformation in the mold, and thus obtaining a sealing cover forging of the desired shape. However, the traditional die forging process has some shortcomings. For example, due to the wear and deformation of the mold, it may be difficult to ensure the dimensional accuracy and surface quality of the forging, and a large amount of subsequent processing is required to correct the dimensional and surface defects, increasing production costs and processing cycles; the abnormal risks of the forging process cannot be discovered in time to make adjustments, increasing the scrap rate of the forgings; in addition, the traditional die forging process is difficult to forge sealing covers of complex shapes, and it is difficult to meet the requirements of modern automotive air springs for the diversification and high performance of sealing covers.

[0003] Chinese patent application publication number CN115401145A discloses a process for forging metal profiles, including 1) cutting the profile to obtain raw materials; 2) placing the raw materials in the raw material placement area at the top of the lower ring die; 3) matching and fixing the upper die part with the lower ring die part; 4) pressing the upper die part and the lower ring die part together to apply pressure to the raw materials, so that the lower protruding part of the raw materials is squeezed into the cavity of the upper die part to obtain the required structure of the metal product; 5) releasing the downward pressure on the upper die part and the lower ring die part, and then separating the upper die part from the lower ring die part to remove the metal product; 6) repeating step 1) to cold forge the next metal product. The raw materials of the invention are cut from the profile with a protruding lower part, and cold forged using a special mold. During forging, the force area of ​​the raw materials is reduced, thereby reducing the forging pressure, thereby improving warm forging to cold forging and simplifying the forging process.

[0004] However, there are still the following problems in the prior art:

[0005] During the forging process, abnormal risks were not controlled in real time and in a timely manner, the impact of the die shape on the forging process was not considered, and the folding of the billet caused by the billet flowing through the flow path was not considered, resulting in low quality and precision of the forged products. Summary of the invention

[0006] To this end, the present invention provides an air spring sealing cover forging process to overcome the problems in the prior art that the influence of the mold shape on the forging process and the folding of the billet caused by the billet flowing through the flow path are not considered, resulting in low quality and precision of the forged product.

[0007] To achieve the above object, the present invention provides an air spring sealing cover forging process, which comprises:

[0008] Calling forging die data corresponding to a number of sealing covers and surface data of a blank stored in a sample database to identify concave-convex features of each forging die, wherein the concave-convex features include the total number of concave areas and convex areas corresponding to the forging die and the concave-convex amplitude;

[0009] Determining stress uniform interference characterization parameters during the forging process according to the concave-convex features of each forging die, so as to cluster each forging die;

[0010] Heating the blank and obtaining the surface characteristics of the heated blank to determine whether to pre-treat the blank;

[0011] Controlling the shearing tool to perform a blanking operation on the blank, and forging the sealing cover according to the clustering result, including:

[0012] Identify the flow path of the billet to determine the easy-folding area of ​​the billet, call the regional forging characteristics of the easy-folding area of ​​the billet in combination with the mean value of the flow velocity of the corresponding flow path to determine the abnormal characterization value of the billet forging, so as to judge whether to adjust the forging parameters;

[0013] Or, maintaining the reference forging parameters to forge the corresponding sealing cover;

[0014] The sealing cover obtained by forging is subjected to a cooling treatment;

[0015] The regional forging characteristics include the mean value of the bending curvature and the number of bends in the edge profile, and the forging parameters include the pressing amount and the pressing speed.

[0016] Furthermore, the process of determining stress uniform interference characterization parameters during the forging process according to the concave-convex features of each of the forging dies includes:

[0017] The ratio of the total number of concave areas and convex areas of the forging die to the total number threshold of the concave areas and convex areas is used as the first stress uniform interference feature;

[0018] The ratio of the concavo-convex amplitude of the forging die to the concavo-convex amplitude threshold is used as the second stress uniform interference feature;

[0019] The sum of the first stress uniform interference feature and the second stress uniform interference feature is used as the stress uniform interference characterization parameter.

[0020] Further, clustering the forging dies includes:

[0021] If the stress uniform interference characterization parameter of any forging die is greater than or equal to the stress uniform interference characterization parameter threshold, the forging die is grouped into a strong interference class;

[0022] If the stress uniform interference characterization parameter of any forging die is less than the stress uniform interference characterization parameter threshold, the forging die is grouped into a weak interference class.

[0023] Furthermore, the process of obtaining the surface characteristics of the heated blank to determine whether to pre-treat the blank includes:

[0024] Calling the surface data of the blank stored in the sample database to extract the surface features of the blank, including the roughness and the morphological error ratio of the blank surface;

[0025] If the surface feature does not meet the standard conditions of the blank surface, pre-treating the blank;

[0026] The standard condition of the blank surface is that the roughness of the blank surface is less than a roughness threshold and the morphological error ratio is less than a morphological error ratio threshold.

[0027] Furthermore, the pretreatment includes grinding and correcting the surface of the blank.

[0028] Further, the sealing cover is forged according to the clustering result, including:

[0029] If the forging die corresponding to the sealing cover belongs to the strong interference type, the flow path of the blank is identified to determine the easy-folding area of ​​the blank, and the regional forging characteristics of the easy-folding area of ​​the blank are called in combination with the mean value of the flow velocity of the corresponding flow path to determine the abnormal characterization value of the blank forging to determine whether to adjust the forging parameters;

[0030] If the forging die corresponding to the sealing cover belongs to the weak interference type, the corresponding sealing cover is forged by maintaining the reference forging parameters.

[0031] Further, the process of determining the easy folding area of ​​the blank includes,

[0032] Identify the flow path of the billet;

[0033] Determine whether there are overlaps in the flow paths in each area of ​​the mold;

[0034] If the overlapping point exists in the region, the region is determined to be an easy-to-fold region of the blank.

[0035] Further, the process of calling the regional forging characteristics of the easy-folding region of the billet in combination with the flow velocity mean of the corresponding flow path to determine the abnormal characterization value of the billet forging includes:

[0036] The sum of the ratio of the mean value of the bending arc to the mean value threshold of the bending arc and the ratio of the number of edge contour bends to the threshold of the number of edge contour bends is taken as the first abnormal feature;

[0037] The ratio of the mean flow velocity of the corresponding flow path to the mean flow velocity threshold is used as the second abnormal feature;

[0038] A weighted sum of the first abnormal feature and the second abnormal feature is taken as an abnormal characterization value of the billet forging.

[0039] Further, determining whether to adjust the forging parameters includes,

[0040] If the abnormal characterization value is greater than or equal to the abnormal characterization threshold, the forging parameters are adjusted.

[0041] Further, the forging parameters are adjusted, including,

[0042] reducing the amount of depression, wherein the amount of depression reduction is positively correlated with the abnormal characterization value;

[0043] reducing the pressing speed, wherein the reduction value of the pressing speed is positively correlated with the abnormal characterization value;

[0044] The forging parameters include the pressing amount and the pressing speed.

[0045] Compared with the prior art, the present invention identifies the concave-convex features of each forging die by calling the forging die data corresponding to several sealing covers and the surface data of the blank stored in the sample database; determines the stress uniform interference characterization parameters of the corresponding sealing cover during forging according to the concave-convex features of each forging die, so as to cluster the forging dies; heats the blank to obtain the surface features of the heated blank to determine whether to pretreat the blank; controls the shearing tool to perform a blank feeding operation, and adaptively forges the sealing cover according to the clustering result; and cools the forged sealing cover. The present invention can reduce the risk of blank folding during the forging process, reduce forging defects caused by stress problems, and improve the forging efficiency of the sealing cover.

[0046] In particular, the present invention considers the concave and convex features of the forging die corresponding to the sealing cover to determine the stress uniformity interference characterization parameters of the sealing cover during the forging process. In actual situations, when the blank flows in the forging die, greater stress will be generated in the raised area and the recessed area accordingly. Therefore, the uneven stress distribution inside the forging die may lead to uneven internal structure of the forged sealing cover, reduce the mechanical properties of the sealing cover, such as strength, toughness and fatigue performance, etc., and affect the sealing performance of the sealing cover. Under the premise, the present invention uses the stress uniformity interference characterization parameters to characterize the degree of stress uniformity of the forging die under the influence of the blank flow interference during the forging process of the sealing cover using the corresponding forging die, and then provide data support for clustering each forging die. The present invention can reduce the risk of blank folding during the forging process, reduce forging defects caused by stress problems, and improve the forging efficiency of the sealing cover.

[0047] In particular, the present invention clusters the forging dies, and for the strong interference forging dies, predetermines the easy-to-fold area of ​​the blank, and dynamically adjusts the forging parameters based on the regional structural characteristics of the determined easy-to-fold area of ​​the blank and the flow rate of the blank, so as to improve the stability and controllability of the forging process. In actual situations, after folding, the streamlines of the blank are disrupted, causing the internal organizational structure of the blank to become disordered, and defects such as inclusions and pores may occur, thereby reducing the strength, toughness and other mechanical properties of the sealing cover, making it easy to break or damage during use. The mean value of the bending curvature of the folding area of ​​the blank and the number of bends in the edge profile often affect each other, and jointly aggravate the risk of blank folding. At the same time, if the flow rate of the blank is too high, the blank will be easily damaged. The greater the speed, the more significant the flow resistance will be when flowing through a predetermined folding area prone to folding. Since the billet needs to change direction when adapting to bending and folding, it needs to overcome greater inertia, which causes the impact force between the billet and the forging die to increase, and produces a stronger stress concentration in the folding area, increasing the risk of forging die wear and billet folding. Therefore, the present invention uses the abnormal characterization value of billet forging to characterize the degree of folding risk and the degree of forging abnormality in the forging process, and provides data support for the subsequent determination of whether to adjust the forging parameters. The present invention can reduce the risk of billet folding during the forging process, reduce forging defects caused by stress problems, and improve the forging efficiency of the sealing cover. BRIEF DESCRIPTION OF THE DRAWINGS

[0048] Figure 1 A schematic diagram of the steps of the forging process of the air spring sealing cover according to an embodiment of the invention;

[0049] Figure 2 A logical decision diagram for clustering various forging dies according to an embodiment of the invention;

[0050] Figure 3A logic decision diagram for pre-processing the blank in accordance with an embodiment of the invention;

[0051] Figure 4 This is a logical decision diagram for determining whether to adjust forging parameters according to an embodiment of the invention. DETAILED DESCRIPTION

[0052] In order to make the objects and advantages of the present invention more clearly understood, the present invention is further described below in conjunction with embodiments; it should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0053] The preferred embodiments of the present invention are described below with reference to the accompanying drawings. It should be understood by those skilled in the art that these embodiments are only used to explain the technical principles of the present invention and are not intended to limit the protection scope of the present invention.

[0054] It should be noted that, in the description of the present invention, the terms such as “inside” and the like indicating directions or positional relationships are based on the directions or positional relationships shown in the accompanying drawings. This is merely for the convenience of description and does not indicate or imply that the device or element must have a specific orientation, be constructed and operated in a specific orientation. Therefore, it cannot be understood as a limitation on the present invention.

[0055] In addition, it should be noted that in the description of the present invention, unless otherwise clearly specified and limited, the term "connection" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection. For those skilled in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0056] See also Figure 1 As shown, it is a schematic diagram of the steps of the forging process of the air spring sealing cover according to the embodiment of the present invention. The forging process of the air spring sealing cover according to the embodiment of the present invention includes:

[0057] Step S1, calling forging die data corresponding to a plurality of sealing covers and surface data of a blank stored in a sample database, and identifying concave-convex features of each forging die, wherein the concave-convex features include the total number of concave areas and convex areas corresponding to the forging die and the concave-convex amplitude;

[0058] Step S2, determining stress uniform interference characterization parameters during the forging process according to the concave-convex features of each forging die, so as to cluster each forging die;

[0059] Step S3, heating the blank and obtaining the surface characteristics of the blank after heating to determine whether to pre-treat the blank;

[0060] Step S4, controlling the shearing tool to perform a blanking operation on the blank, and forging the sealing cover according to the clustering result, including:

[0061] Identify the flow path of the billet to determine the easy-folding area of ​​the billet, call the regional forging characteristics of the easy-folding area of ​​the billet in combination with the mean value of the flow velocity of the corresponding flow path to determine the abnormal characterization value of the billet forging, so as to judge whether to adjust the forging parameters;

[0062] Or, maintaining the reference forging parameters to forge the corresponding sealing cover;

[0063] Step S5, cooling the sealing cover obtained by forging;

[0064] The regional forging characteristics include the mean value of the bending curvature and the number of bends in the edge profile, and the forging parameters include the pressing amount and the pressing speed.

[0065] Specifically, there is no limitation on the specific method of identifying the concave and convex features of each forging die. During implementation, the concave areas and convex areas in the die cavity of the forging die can be obtained based on the three-dimensional model of the forging die, and then the total number of concave areas and convex areas can be determined. The concave and convex amplitude is determined based on the average concave amplitude of the concave area and the average convex amplitude of the convex area, and is set to the average of the average concave amplitude and the average convex amplitude. This will not be repeated.

[0066] Among them, the area with a concave amplitude greater than 1 cm is determined as a concave area, and the area with a convex amplitude greater than 1 cm is determined as a convex area.

[0067] Specifically, there is no limitation on the type of shearing tool, which may be any device that can realize the corresponding function in the prior art, such as a CNC sawing machine, a hydraulic shearing machine, etc.

[0068] Specifically, there is no specific limitation on the method for obtaining the regional forging characteristics of the easy-folding area of ​​the billet. In implementation, the forging die data may be stored in a relevant database in advance, and the regional forging characteristics of the easy-folding area of ​​the billet may be obtained by calling the relevant database.

[0069] The forging die data include the size parameters, material properties, the average value of the bending curvature of each area, and the number of bends in the edge contour of the area, etc.

[0070] Specifically, the mean value of the bending radian is predetermined, a plurality of sections are constructed inside the die, the inner contour of the forging die is determined at each section, the maximum bending radian of each inner contour segment in each section is calculated, and the mean value of the maximum bending radian is solved as the mean value of the bending radian;

[0071] Similarly, the number of bends in the edge profile is predetermined, and a plurality of sections are constructed inside the three-dimensional model corresponding to the forging die. The internal contour of the forging die is determined in each section, the bend profile segment is determined, and the average number of bend profile segments in each section is determined to obtain the number of bends in the edge profile.

[0072] Among them, the bending contour segment is an internal contour segment with a bending curvature greater than a predetermined bending curvature threshold. All constructed sections pass through the center of the forging die, the angles between the sections are equal, and the sections are perpendicular to the horizontal plane. It can be understood that the more sections there are, the finer the forging die can be divided. Preferably, 8 sections can be selected, which will not be repeated here.

[0073] The bending arc threshold is selected in the interval [0.25rad / cm, 0.5rad / cm].

[0074] Specifically, the process of determining the stress uniform interference characterization parameters during the forging process according to the concave-convex features of each forging die includes:

[0075] The ratio of the total number of concave areas and convex areas of the forging die to the total number threshold of the concave areas and convex areas is used as the first stress uniform interference feature;

[0076] The ratio of the concavo-convex amplitude of the forging die to the concavo-convex amplitude threshold is used as the second stress uniform interference feature;

[0077] The sum of the first stress uniform interference feature and the second stress uniform interference feature is used as the stress uniform interference characterization parameter.

[0078] In this embodiment, the total number threshold and the concave-convex amplitude threshold corresponding to the concave area and the convex area are set to characterize the situation that the structure inside the forging die is relatively complex and the stress distribution is uneven, and the total number threshold and the concave-convex amplitude threshold corresponding to the concave area and the convex area are determined by the total number average value and the concave-convex amplitude average value corresponding to the concave area and the convex area;

[0079] By acquiring and inspecting several forging dies, the total number data corresponding to the concave areas and the convex areas and the average value of the concave-convex amplitude obtained by the inspection are solved, and based on the total number data corresponding to the concave areas and the convex areas and the average value of the concave-convex amplitude, the total number average value and the average value of the concave-convex amplitude corresponding to the concave areas and the convex areas are determined. Based on the purpose of setting the above two thresholds in this embodiment, the total number threshold value corresponding to the concave areas and the convex areas is determined between 1.12 times and 1.16 times the total number average value corresponding to the concave areas and the convex areas, and the concave-convex amplitude average threshold value is determined between 1.04 times and 1.09 times the concave-convex amplitude average value.

[0080] Specifically, the present invention considers the concave-convex features of the forging die corresponding to the sealing cover to determine the interference characterization parameters of the uniform stress of the sealing cover during the forging process. In actual situations, when the blank flows in the forging die, a relatively large stress will be generated on the raised area and the recessed area. For example, when the blank flows through the raised area, the blank needs to bypass or fill the raised part. In this process, the surface of the raised area will be subjected to the local stress applied by the blank, and the structural shape of the raised area itself usually leads to stress concentration. When the blank flows through the part, the stress distribution of the part will no longer be uniform, which accelerates the wear and deformation of the forging die.

[0081] When the billet flows through the concave area, the concave area needs to be filled, which will generate pressure on the inner wall of the concave area. If the concave amplitude of the concave area is too large, a large pressure is required when the billet is filled, so that the inner wall of the concave area is subjected to a large stress. At the same time, the position of the concave area will affect the flow path of the billet, resulting in uneven stress distribution, so that the forging die is subjected to different degrees of load during the forging process, causing local deformation or damage;

[0082] Therefore, under the above circumstances, the internal structure of the forged sealing cover may be uneven, which may reduce the mechanical properties of the sealing cover, such as strength, toughness and fatigue performance, and affect the sealing performance of the sealing cover. In the present invention, stress uniform interference characterization parameters are used to characterize the uniformity of stress distribution of the forging die under the influence of billet flow interference during the forging process of the sealing cover using the corresponding forging die, and then provide data support for clustering each forging die. The present invention can reduce the risk of billet folding during the forging process, reduce forging defects caused by stress problems, and improve the forging efficiency of the sealing cover.

[0083] Specifically, see Figure 2 As shown, it is a logical decision diagram for clustering each forging die in an embodiment of the present invention, and clustering each forging die includes:

[0084] If the stress uniform interference characterization parameter of any forging die is greater than or equal to the stress uniform interference characterization parameter threshold, the forging die is grouped into a strong interference class;

[0085] If the stress uniform interference characterization parameter of any forging die is less than the stress uniform interference characterization parameter threshold, the forging die is grouped into a weak interference class.

[0086] The threshold value of the stress uniformity interference parameter is selected within the range [2.14, 2.21].

[0087] Specifically, see Figure 3As shown, it is a logic determination diagram for pre-processing the blank in an embodiment of the present invention. The process of obtaining the surface characteristics of the heated blank to determine whether to pre-process the blank includes:

[0088] Calling the surface data of the blank stored in the sample database to extract the surface features of the blank, including the roughness and the morphological error ratio of the blank surface;

[0089] If the surface feature does not meet the standard conditions of the blank surface, pre-treating the blank;

[0090] If the surface characteristics meet the standard conditions of the blank surface, there is no need to pre-treat the blank;

[0091] The standard condition of the blank surface is that the roughness of the blank surface is less than a roughness threshold and the morphological error ratio is less than a morphological error ratio threshold.

[0092] In this embodiment, by acquiring the surface data of the same batch of billets, calling the roughness data of the billet surface and the morphological error ratio data of the billet surface, the roughness mean and the morphological error ratio mean are solved. Since the purpose of setting the roughness threshold and the morphological error ratio threshold of the billet surface in this embodiment is to characterize the situation where the surface condition of the billet is poor and the impact on the forging process is serious, the roughness threshold is determined between 0.87 and 0.95 times the roughness mean, and the morphological error ratio threshold is determined between 1.05 and 1.1 times the morphological error ratio mean.

[0093] Specifically, the roughness of the billet surface refers to the microscopic geometric shape error of the billet blank surface, which can reflect the microscopic unevenness of the billet blank surface. If the roughness is too high, the unevenness of the blank surface will cause uneven resistance to the billet during flow. For example, in local raised areas, metal flow is difficult; in recessed areas, the billet may be excessively accumulated, resulting in disordered billet flow, making it difficult to fill the forging die cavity in an ideal way, affecting the dimensional accuracy and shape accuracy of the forging. Among them, the roughness can be detected based on a roughness detector, which will not be repeated here.

[0094] Specifically, the morphological error ratio of the blank surface is pre-detected, which is the ratio of the difference between the actual volume of the blank and the standard volume to the standard volume. The actual volume of the blank can be obtained by acquiring point cloud data using a laser scanning device and modeling the blank. Of course, other methods can also be used, which will not be repeated here.

[0095] Specifically, the pretreatment includes grinding and correcting the surface of the blank.

[0096] It is understandable that the surface finish of the blank is improved by grinding, and the surface of the blank is ground using a grinder and different types of grinding wheels, such as a ceramic grinding wheel, a resin grinding wheel, etc. When the surface of the blank is ground, the abrasive grains of the grinding wheel will remove the particle protrusions on the surface of the blank to make the surface smoother; the blank is mounted on the grinder, and the inclined surface is ground using the grinding wheel. For a smaller morphological error ratio, a one-time grinding method can be used; for a larger morphological error ratio, multiple grinding methods are used, and a small amount of material is removed each time to ensure grinding accuracy and surface quality.

[0097] Specifically, the sealing cover is forged according to the clustering results, including:

[0098] If the forging die corresponding to the sealing cover belongs to the strong interference type, the flow path of the blank is identified to determine the easy-folding area of ​​the blank, and the regional forging characteristics of the easy-folding area of ​​the blank are called in combination with the mean value of the flow velocity of the corresponding flow path to determine the abnormal characterization value of the blank forging to determine whether to adjust the forging parameters;

[0099] If the forging die corresponding to the sealing cover belongs to the weak interference type, the corresponding sealing cover is forged by maintaining the reference forging parameters.

[0100] Specifically, the process of determining the easy folding area of ​​the blank includes:

[0101] Identify the flow path of the billet;

[0102] Determine whether there are overlaps in the flow paths in each area of ​​the mold;

[0103] If the overlapping point exists in the region, the region is determined to be an easy-to-fold region of the blank.

[0104] It is understandable that the stress of the forging die will cause stress deformation in the blank, and then flow in a predetermined path in the forging die. For the identification of the flow path, numerical simulation technology can be used, such as finite element analysis software (such as Deform, ABAQUS, etc.), which can simulate the flow law of the forging die during the forging process and then determine the flow path. This will not be elaborated here.

[0105] Specifically, the process of calling the regional forging characteristics of the easy-folding region of the billet in combination with the flow velocity mean of the corresponding flow path to determine the abnormal characterization value of the billet forging includes:

[0106] The sum of the ratio of the mean value of the bending arc to the mean value threshold of the bending arc and the ratio of the number of edge contour bends to the number threshold of edge contour bends is taken as the first abnormal feature;

[0107] The ratio of the mean flow velocity of the corresponding flow path to the mean flow velocity threshold is used as the second abnormal feature;

[0108] A weighted sum of the first abnormal feature and the second abnormal feature is taken as an abnormal characterization value of the billet forging.

[0109] When performing weighted summation in this implementation, the weight of the first abnormal feature is set to 0.55, and the weight of the second abnormal feature is set to 0.45;

[0110] In this embodiment, the purpose of setting the mean value threshold of the bending arc and the threshold of the number of bends in the edge profile is to characterize the situation where the flow path has a greater impact on the folding of the blank, and the purpose of setting the flow speed of the flow path is to characterize the situation where the flow of the flow path has a greater impact on the easy-to-fold area of ​​the blank. The above two situations are combined to further highlight the stress concentration phenomenon, and the severity is aggravated;

[0111] The bending curvature mean threshold, the edge contour bending number threshold and the flow speed threshold are respectively predetermined, wherein,

[0112] For the bending curvature mean value threshold and the edge profile bending number threshold, this embodiment obtains the forging die data corresponding to the forging process completed several times, calls the bending curvature mean value data and the edge profile bending number data, and solves the average value of the bending curvature mean value and the average value of the edge profile bending number. Based on the purpose of setting the above two thresholds, the bending curvature mean value threshold is determined between 0.92 times and 0.95 times the average value of the bending curvature mean value, and the edge profile bending number threshold is determined between 1.12 times and 1.16 times the average value of the edge profile bending number.

[0113] For the flow velocity threshold of the flow path, this embodiment obtains relevant process history data of completing the forging process for several times, calls the flow velocity history data of the flow path, solves the flow velocity mean, and for the purpose of setting the flow velocity threshold of the flow path, determines the flow velocity threshold between 0.94 times and 0.97 times the flow velocity mean.

[0114] It is understandable that the flow velocity of the flow path refers to the flow velocity of the blank in the flow path. Infrared perspective equipment can be used to obtain the actual flow conditions of the blank, and then determine the flow velocity of the blank in the flow path, which will not be repeated here.

[0115] Specifically, see Figure 4 As shown, it is a logical determination diagram for determining whether to adjust the forging parameters in an embodiment of the present invention. The determination of whether to adjust the forging parameters includes:

[0116] If the abnormal characterization value is greater than or equal to the abnormal characterization threshold, the forging parameters are adjusted;

[0117] If the abnormal characterization value is less than the abnormal characterization threshold, there is no need to adjust the forging parameters.

[0118] The anomaly characterization threshold is selected in the interval [1.67, 1.84].

[0119] Specifically, the forging parameters are adjusted, including,

[0120] reducing the amount of depression, wherein the amount of depression reduction is positively correlated with the abnormal characterization value;

[0121] reducing the pressing speed, wherein the reduction value of the pressing speed is positively correlated with the abnormal characterization value;

[0122] The forging parameters include the pressing amount and the pressing speed.

[0123] In this embodiment, optionally,

[0124] The abnormality characterization value is compared with a preset first abnormality characterization comparison threshold and a second abnormality characterization comparison threshold,

[0125] When the abnormality characterization value is greater than the second abnormality characterization comparison threshold, the reduction amount of the depression amount is determined to be the first reduction amount, and the first reduction amount is set to be 0.45 times the reference depression amount;

[0126] When the abnormal characterization value is greater than or equal to the first abnormal characterization comparison threshold and less than or equal to the second abnormal characterization comparison threshold, the reduction amount of the depression amount is determined to be the second reduction amount, and the second reduction amount is set to be 0.37 times the reference depression amount;

[0127] When the abnormality characterization value is less than the first abnormality characterization comparison threshold, the reduction amount of the depression amount is determined to be the third reduction amount, and the third reduction amount is set to be 0.28 times of the reference depression amount;

[0128] The first abnormal characterization comparison threshold is 1.1 times the abnormal characterization threshold, and the second abnormal characterization comparison threshold is 1.3 times the abnormal characterization threshold.

[0129] It can be understood that the amount of reduction refers to the single compression amount in the height direction of the blank in the forging die cavity under the action of the press slider or hammer head. Usually, multiple reductions are required to complete the forging. For example, when forging on a hot die forging press, after the blank is placed in the forging die, as the press slider descends, each downward movement corresponds to a reduction amount, and the blank is gradually compressed. This will not be repeated.

[0130] In this embodiment, optionally,

[0131] The abnormality characterization value is compared with a preset first abnormality characterization comparison threshold and a second abnormality characterization comparison threshold,

[0132] When the abnormality characterization value is greater than the second abnormality characterization comparison threshold, the reduction value of the pressing speed is determined to be the first reduction value, and the first reduction value is set to be 0.4 times the reference pressing speed;

[0133] When the abnormality characterization value is greater than or equal to the first abnormality characterization comparison threshold and less than or equal to the second abnormality characterization comparison threshold, the reduction value of the pressing speed is determined to be the second reduction value, and the second reduction value is set to be 0.3 times the reference pressing speed;

[0134] When the abnormality characterization value is less than the first abnormality characterization comparison threshold, the reduction value of the pressing speed is determined to be a third reduction value, and the third reduction value is set to be 0.2 times of the reference pressing speed;

[0135] The first abnormal characterization comparison threshold is 1.1 times the abnormal characterization threshold, and the second abnormal characterization comparison threshold is 1.3 times the abnormal characterization threshold.

[0136] Specifically, the pressing speed refers to the speed at which the slide or hammer of the press presses presses downward during the forging process. Properly reducing the pressing speed can give the blank more time to flow evenly and reduce the folding caused by too fast metal flow.

[0137] Regarding the reference pressing speed, those skilled in the art can determine it according to the selected forging process, such as hot forging or warm forging, which will not be elaborated here.

[0138] Specifically, the present invention clusters the forging dies, and for the strong interference forging dies, predetermines the easy-folding area of ​​the blank, and dynamically adjusts the forging parameters in combination with the regional structural characteristics of the determined easy-folding area of ​​the blank and the flow velocity of the blank, so as to improve the stability and controllability of the forging process. In actual situations, after folding, the streamline of the blank is disrupted, so that the internal organizational structure of the blank is disordered, and defects such as inclusions and pores may occur, thereby reducing the strength, toughness and other mechanical properties of the sealing cover, making it easy to break or damage during use;

[0139] For example, the folded part of the billet may contain air to form pores, or contain impurities such as oxide scale produced during the forging process, which seriously affects the quality of the sealing cover. The mean value of the curvature of the billet folding area and the number of edge contour bends often affect each other, and together increase the risk of billet folding. For example, in an area with a large mean value of the curvature and a large number of edge contour bends, the resistance to billet flow will be greater, the degree of flow turbulence will be more serious, and the stress concentration phenomenon will be more prominent. In this case, the possibility of billet folding will increase significantly, and once folding occurs, the severity will also be higher;

[0140] At the same time, if the flow speed of the billet is higher, the flow resistance will be more significant when it flows through the predetermined folding area where folding is prone to occur. Since the billet needs to change direction when adapting to bending and folding, it needs to overcome greater inertia, resulting in an increase in the impact force between the billet and the forging die, and a stronger stress concentration is generated in the folding area, increasing the risk of forging die wear and billet folding;

[0141] Therefore, the present invention uses the abnormal characterization value of the billet forging to characterize the folding risk degree and the forging abnormality degree in the forging process, and provides data support for the subsequent determination of whether to adjust the forging parameters. The present invention can reduce the risk of billet folding during the forging process, reduce forging defects caused by stress problems, and improve the forging efficiency of the sealing cover.

[0142] So far, the technical solutions of the present invention have been described in conjunction with the preferred embodiments shown in the accompanying drawings. However, it is easy for those skilled in the art to understand that the protection scope of the present invention is obviously not limited to these specific embodiments. Without departing from the principle 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 fall within the protection scope of the present invention.

Claims

1. A forging process for an air spring sealing cover, characterized in that: include: Calling forging die data corresponding to a plurality of sealing covers and surface data of a blank stored in a sample database to identify concave-convex features of each forging die, wherein the concave-convex features include the total number of concave areas and convex areas corresponding to the forging die and the concave-convex amplitude; Determining stress uniform interference characterization parameters during the forging process according to the concave-convex features of each forging die, so as to cluster each forging die; Heating the blank and obtaining the surface characteristics of the heated blank to determine whether to pre-treat the blank; Controlling the shearing tool to perform a blanking operation on the blank, and forging the sealing cover according to the clustering result, including: Identify the flow path of the billet to determine the easy-folding area of ​​the billet, call the regional forging characteristics of the easy-folding area of ​​the billet in combination with the mean value of the flow velocity of the corresponding flow path to determine the abnormal characterization value of the billet forging, so as to judge whether to adjust the forging parameters; Or, maintaining the reference forging parameters to forge the corresponding sealing cover; The sealing cover obtained by forging is subjected to a cooling treatment; The regional forging characteristics include the mean value of the bending curvature and the number of bends in the edge profile, and the forging parameters include the pressing amount and the pressing speed.

2. The air spring sealing cover forging process according to claim 1, characterized in that: The process of determining stress uniform interference characterization parameters during the forging process according to the concave-convex features of each forging die includes: The ratio of the total number of concave areas and convex areas of the forging die to the total number threshold of the concave areas and convex areas is used as the first stress uniform interference feature; The ratio of the concavo-convex amplitude of the forging die to the concavo-convex amplitude threshold is used as the second stress uniform interference feature; The sum of the first stress uniform interference feature and the second stress uniform interference feature is used as the stress uniform interference characterization parameter.

3. The air spring sealing cover forging process according to claim 1, characterized in that: Clustering each of the forging dies includes: If the stress uniform interference characterization parameter of any forging die is greater than or equal to the stress uniform interference characterization parameter threshold, the forging die is grouped into a strong interference class; If the stress uniform interference characterization parameter of any forging die is less than the stress uniform interference characterization parameter threshold, the forging die is grouped into a weak interference class.

4. The air spring sealing cover forging process according to claim 1, characterized in that: The process of obtaining the surface characteristics of the heated blank to determine whether to pre-treat the blank includes: Calling the surface data of the blank stored in the sample database to extract the surface features of the blank, including the roughness and the morphological error ratio of the blank surface; If the surface feature does not meet the standard conditions of the blank surface, pre-treating the blank; The standard condition of the blank surface is that the roughness of the blank surface is less than a roughness threshold and the morphological error ratio is less than a morphological error ratio threshold.

5. The air spring sealing cover forging process according to claim 4, characterized in that: The pre-processing includes grinding and correcting the surface of the blank.

6. The air spring sealing cover forging process according to claim 3, characterized in that: The sealing cover is forged according to the clustering results, including: If the forging die corresponding to the sealing cover belongs to the strong interference type, the flow path of the blank is identified to determine the easy-folding area of ​​the blank, and the regional forging characteristics of the easy-folding area of ​​the blank are called in combination with the mean value of the flow velocity of the corresponding flow path to determine the abnormal characterization value of the blank forging to determine whether to adjust the forging parameters; If the forging die corresponding to the sealing cover belongs to the weak interference type, the corresponding sealing cover is forged by maintaining the reference forging parameters.

7. The air spring sealing cover forging process according to claim 1, characterized in that: The process of determining the easy folding area of ​​the blank includes, Identify the flow path of the billet; Determine whether there are overlaps in the flow paths in each area of ​​the mold; If the overlapping point exists in the region, the region is determined to be an easy-to-fold region of the blank.

8. The air spring sealing cover forging process according to claim 1, characterized in that: The process of calling the regional forging characteristics of the easy-folding region of the billet in combination with the flow velocity mean of the corresponding flow path to determine the abnormal characterization value of the billet forging includes: The sum of the ratio of the mean value of the bending arc to the mean value threshold of the bending arc and the ratio of the number of edge contour bends to the number threshold of edge contour bends is taken as the first abnormal feature; The ratio of the mean flow velocity of the corresponding flow path to the mean flow velocity threshold is used as the second abnormal feature; A weighted sum of the first abnormal feature and the second abnormal feature is taken as an abnormal characterization value of the billet forging.

9. The air spring sealing cover forging process according to claim 8, characterized in that: Determine whether to adjust forging parameters, including, If the abnormal characterization value is greater than or equal to the abnormal characterization threshold, the forging parameters are adjusted.

10. The air spring sealing cover forging process according to claim 9, characterized in that: Adjust forging parameters, including, reducing the amount of depression, wherein the amount of depression reduction is positively correlated with the abnormal characterization value; reducing the pressing speed, wherein the reduction value of the pressing speed is positively correlated with the abnormal characterization value; The forging parameters include the pressing amount and the pressing speed.

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