A forging process for an air suspension aluminum cylinder assembly

Abstract

The present invention relates to the field of forging technology, and in particular to a forging process for an aluminum cylinder component of an air suspension. The present invention places a pre-forged blank in a forging die, pre-forges the pre-forged blank, divides the forging surface into a plurality of annular areas, obtains point cloud data of a plurality of points in each annular area in real time during the pre-forging process, terminates the pre-forging based on the change of characteristic coordinate values, screens the bulge characterization area, determines whether the shape change of the pre-forged blank is abnormal, forges the pre-forged blank with abnormal shape change in a forging compensation manner to obtain a forged part, and anneals the forged part to obtain an aluminum cylinder forging part. Furthermore, the forming shape stability of the special-shaped forging part is analyzed according to the local deformation state of the material during the forging process, and the forging method is adaptively adjusted according to the difference in material state, thereby improving the shape and size accuracy and performance consistency of the special-shaped aluminum cylinder forging part of the air suspension.

Description

Technical Field

[0001] The invention relates to the technical field of forging, and in particular to a forging process for an air suspension aluminum cylinder component. Background Art

[0002] With the continuous improvement of global requirements for automobile fuel economy and environmental protection, automobile lightweighting has become an important trend in the development of the industry. Compared with traditional suspension systems, air suspension systems can provide better ride comfort and vehicle handling under the premise of lightweight automobiles. As a key component, the performance of the air suspension aluminum tube assembly directly affects the performance of the entire suspension system. The forging process can produce aluminum tube assemblies with complex shapes and high precision. Through forging, the internal structure of the aluminum alloy can be made denser and more uniform, and the strength and toughness of the material can be improved. When manufacturing air suspension aluminum tube assemblies with traditional casting processes, forging technology mainly focuses on the overall forging process parameter setting, such as uniform forging speed, holding time, etc., and as the complexity of the forging die shape continues to increase, a single process parameter setting cannot guarantee the quality and performance of air suspension forging. Therefore, improving the performance consistency and stability of the forging of air suspension aluminum tube assemblies is a technical problem that needs to be solved urgently.

[0003] For example, the Chinese patent application publication number: CN118218522A, the invention discloses a forging method of an aluminum alloy conical cylinder, including the following steps: S1, heating the aluminum alloy ingot to 440-480°C and keeping it warm for a period of time; S2, transferring the ingot after heating and keeping warm to a forging platform for forging and blanking to form a forged blank; S3, placing the forged blank into a mold for die forging to form a die forging blank; S4, after the die forging is completed, using a leaking die to punch The intermediate billet is formed by piercing the skin; S5, transferring the intermediate billet to the horse frame expansion cone mechanism and expanding it to the required size; S6, heating the conical tube obtained in S5 to 470-503°C, keeping it warm for a period of time, and then immediately transferring it to cooling water; S7, after quenching, heating the conical tube to 160-180°C, keeping it warm for a period of time to obtain the final aluminum alloy conical tube. The forging method of the aluminum alloy conical tube provided in this application has the advantages of high material utilization, high processing efficiency and low cost.

[0004] The prior art still has the following problems:

[0005] The existing technology cannot analyze the forming shape stability of special-shaped forgings according to the local deformation state of the material during the forging process, and cannot adaptively adjust the forging method according to the difference in material state, which affects the shape, size accuracy and performance consistency of the special-shaped aluminum tube forgings of the air suspension. Summary of the invention

[0006] To this end, the present invention provides an air suspension aluminum cylinder assembly forging process to overcome the problems that the prior art cannot analyze the forming shape stability of special-shaped forgings according to the local deformation state of the material during the forging process, and cannot adaptively adjust the forging method according to the difference in material state.

[0007] To achieve the above object, the present invention provides a forging process for an air suspension aluminum cylinder assembly, comprising:

[0008] Placing a preforged blank in a forging die, and preforging the preforged blank, wherein the preforging comprises controlling the forging die to forge a forging surface of the preforged blank;

[0009] The forging surface is divided into a plurality of annular regions with equal annular widths, point cloud data of a plurality of points in each annular region during the pre-forging process are acquired in real time, and characteristic coordinate values ​​of each point are determined based on the point cloud data;

[0010] Based on the change of characteristic coordinate values ​​of several points in each annular area, the pre-forging is terminated and the uplift characterization area is screened, and whether the shape change of the pre-forged blank is abnormal is determined according to the distribution of characteristic points in the uplift characterization area;

[0011] Wherein, the characteristic points are determined according to the characteristic coordinate values ​​of each point;

[0012] Forging the pre-forged billet with abnormal shape change in a forging compensation manner to obtain a forged part;

[0013] The forging compensation method includes determining the deformation category of the pre-forging billet according to the duration of the pre-forging process, and selecting and adjusting the holding time of the forging die according to the deformation category of the pre-forging billet, or setting a number of forging pause points during the forging process;

[0014] The adjustment amount of the holding time and the number of times the forging pause points are set are determined according to the outer contour parameters of the forged reference part, and the outer contour parameters are determined based on the height and width of the outer step;

[0015] The forged part is annealed to obtain an aluminum cylinder forged part.

[0016] Furthermore, determining the characteristic coordinate value of each point includes:

[0017] Taking the midpoint of the forging surface as the coordinate origin, a three-dimensional rectangular coordinate system is established;

[0018] Obtain the three-dimensional rectangular coordinates of several points in each annular area;

[0019] The coordinate values ​​perpendicular to the forging surface direction in the three-dimensional rectangular coordinates are determined as the characteristic coordinate values ​​of each point.

[0020] Further, the process of terminating the pre-forging and screening the ridge characterization area includes:

[0021] If the average value of the characteristic coordinate values ​​of several points in the annular region meets the explicit condition of forging surface bulge, the pre-forging is terminated and the annular region is selected as a bulge characterization region;

[0022] The dominant condition for the forging surface bulge is that the average value of the characteristic coordinate value exceeds a preset characteristic coordinate reference value.

[0023] Furthermore, the process of determining the characteristic points in the ridge characterization area includes:

[0024] Calculate the average value of characteristic coordinate values ​​of a plurality of points in the uplift characterization area;

[0025] Points whose characteristic coordinate values ​​of several points in the ridge characterization area exceed the average value are determined as the characteristic points.

[0026] Further, the process of determining whether the shape change of the pre-forged blank is abnormal includes:

[0027] Taking the midpoint of the forging surface as the center of the circle, the ridge characterization area is divided into a plurality of ridge characterization sector ring areas at a preset center angle;

[0028] Obtain the number of characteristic points in each ridge representation sector ring area;

[0029] If the number of characteristic points in each bulge characterization sector ring region does not meet the normal bulge characterization condition, it is determined that the shape change of the pre-forged billet is abnormal;

[0030] The normal condition for uplift characterization is that the difference between the number of characteristic points in each uplift characterization sector ring region and the number of characteristic points in the remaining uplift characterization sector ring regions does not exceed a preset difference threshold.

[0031] Furthermore, the process of determining the deformation category of the pre-forged billet includes:

[0032] If the pre-forged billet with abnormal shape change meets the first abnormal category condition, the deformation category of the pre-forged billet is determined to be the first deformation abnormal category;

[0033] If the pre-forged billet with abnormal shape change does not meet the first abnormal category condition, the deformation category of the pre-forged billet is determined to be the second deformation abnormal category.

[0034] Furthermore, the first abnormal category condition is that the duration of the pre-forging process does not exceed a preset duration reference value.

[0035] Further, the forging compensation method for the pre-forged blank is selected to include:

[0036] If the deformation category of the pre-forged blank is the first abnormal deformation category, a forging compensation method for the pre-forged blank is selected to set a number of forging pause points during the forging process according to the outer contour parameters of the forging reference piece;

[0037] If the deformation category of the pre-forged billet is the second abnormal deformation category, the forging compensation method selected for the pre-forged billet is to adjust the holding time of the forging die according to the outer contour parameters of the forging reference part.

[0038] Furthermore, the adjustment amount of the holding time is positively correlated with the outer contour parameter, and the setting number of the forging pause point is positively correlated with the outer contour parameter.

[0039] Furthermore, the outer contour parameter is the ratio of the height to the width of the outer step.

[0040] Compared with the prior art, the beneficial effect of the present invention lies in that the present invention places a pre-forged billet in a forging die and pre-forges the pre-forged billet, wherein the pre-forging includes controlling the forging die to forge the forging surface of the pre-forged billet, dividing the forging surface into a plurality of annular areas with equal ring widths, acquiring point cloud data of a plurality of points in each annular area in real time during the pre-forging process, determining the characteristic coordinate value of each point based on the point cloud data, terminating the pre-forging based on the change of the characteristic coordinate values ​​of a plurality of points in each annular area and screening the bulge characterization area, determining whether the shape change of the pre-forged billet is abnormal according to the distribution of the characteristic points in the bulge characterization area, forging the pre-forged billet with abnormal shape change in a forging compensation manner to obtain a forged part, and annealing the forged part to obtain an aluminum cylinder forging part, thereby realizing the analysis of the forming shape stability of the special-shaped forging according to the local deformation state of the material during the forging process, and the adaptive adjustment of the forging method according to the difference in material state, thereby improving the shape and size accuracy and performance consistency of the special-shaped aluminum cylinder forging part of the air suspension.

[0041] In particular, the present invention terminates pre-forging and screens the bulge characterization area by the change of the characteristic coordinate values ​​of several points in each annular area. It can be understood that when the metal billet is pre-forged, the internal stress concentration of the metal will cause a bulge in the forged position, and the points in the bulge area will obviously rise in the direction perpendicular to the forging surface. During the pre-forging process, these obviously risen positions can provide scientific data support for the subsequent judgment of whether the shape change of the pre-forged billet is abnormal, and help to take targeted measures to adjust the forging process, correct shape abnormalities, and ensure product quality. The present invention terminates pre-forging and screens the bulge characterization area by the change of the characteristic coordinate values ​​of several points in each annular area, thereby achieving the acquisition of several points with data representation during the pre-forging process, thereby improving the shape and size accuracy and performance consistency of the special-shaped aluminum tube forgings of the air suspension.

[0042] In particular, the present invention determines whether the shape change of the pre-forged billet is abnormal by the distribution of characteristic points in the uplift characterization area. It can be understood that the characteristic points represent the positions where the shape changes are more obvious in the uplift characterization area. The number of characteristic points in each uplift characterization fan ring area is obtained, and the degree of shape change in each sub-area can be expressed from the perspective of quantity, thereby characterizing whether the uplift phenomenon of the uplift characterization area as a whole is uniform. If the number of characteristic points in each uplift characterization fan ring area is significantly different from the number of characteristic points in the remaining uplift characterization fan ring areas, then the uplift phenomenon of the uplift characterization area as a whole is uneven. The present invention determines whether the shape change of the pre-forged billet is abnormal by the distribution of characteristic points in the uplift characterization area, thereby realizing the analysis of the forming shape stability of the special-shaped forgings according to the local deformation state of the material during the forging process, thereby improving the shape and size accuracy and performance consistency of the special-shaped aluminum cylinder forgings of the air suspension.

[0043] In particular, the present invention determines the deformation category of the pre-forged billet by the duration of the pre-forging process. It can be understood that during the pre-forging process, there is a stress difference inside the pre-forging billet. For metals with poor fluidity, the internal stress balance process is relatively slow. Due to the poor fluidity, the forging die needs to forge the forging surface of the pre-forged billet for a longer period of time before the deformation of the forging surface reaches a data-representative deformation. Therefore, the internal fluidity difference of the material itself can be judged according to the difference in the speed of change of the bulge deformation amount of the forging surface of the forging during the forging process. The present invention determines the deformation category of the pre-forging billet by the duration of the pre-forging process, and further, realizes the adaptive adjustment of the forging method according to the difference in material state, thereby improving the shape and size accuracy and performance consistency of the special-shaped aluminum tube forgings of the air suspension.

[0044] In particular, under the condition that the deformation category of the preforged billet is the first deformation abnormality category, the present invention selects a forging compensation method for the preforged billet as setting a number of forging pause points during the forging process of the preforged billet. It can be understood that when the preforged billet is the first deformation abnormality category, the fluidity of the preforged billet is characterized by good fluidity, and the flow speed of the preforged billet is relatively fast during the preforging process. In this case, the stress distribution inside the preforged billet also changes relatively rapidly. In the pause gap of the forging pause point, the stress inside the preforged billet will be adjusted through the elasticity and plastic deformation of the preforged billet itself. By setting multiple forging pause points, the stress distribution can be adjusted multiple times during the entire preforging process. Each pause provides an opportunity for the preforged billet to relax stress, and then, the forging method is adaptively adjusted according to the difference in material state, thereby improving the shape and size accuracy and performance consistency of the special-shaped aluminum cylinder forgings of the air suspension.

[0045] In particular, under the condition that the deformation category of the preforged billet is the second abnormal deformation category, the present invention selects a forging compensation method for the preforged billet as adjusting the holding time of the forging die according to the external contour parameters of the forging reference part. It can be understood that when the preforged billet is the second abnormal deformation category, the internal organizational structure of the preforged billet makes it relatively difficult for the preforged billet to deform under pressure, and a certain amount of time and continuous pressure are required to achieve the expected deformation amount. The external contour parameters of the forging reference part can characterize the degree of deformation of the special-shaped part of the forging part, and the height and width of the external step can characterize the degree of deformation of the special-shaped part of the forging part. The larger the ratio is, the greater the degree of deformation of the special-shaped part of the forging, which means that the pre-forged billet needs to overcome greater resistance at this position and more time is needed to complete the forging. Adjusting the holding time can make the forging process more precise. For forgings with a large degree of deformation in special-shaped parts, appropriately extending the holding time can allow the pre-forged billet enough time to deform in this complex shape area. Furthermore, the forging method is adaptively adjusted according to the difference in material state, thereby improving the shape and size accuracy and performance consistency of the special-shaped aluminum cylinder forgings of the air suspension. BRIEF DESCRIPTION OF THE DRAWINGS

[0046] Figure 1 This is a step diagram of a forging process for an aluminum cylinder assembly of an air suspension according to an embodiment of the present invention;

[0047] Figure 2 A diagram showing the steps of determining the characteristic coordinate values ​​of each point according to an embodiment of the present invention;

[0048] Figure 3 A logic flow chart for selecting an adjustment method for forging a pre-forged blank for an embodiment of the present invention;

[0049] Figure 4 Schematic diagram of the height and width of the surface steps of a forged reference piece according to an embodiment of the present invention. DETAILED DESCRIPTION

[0050] 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.

[0051] 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.

[0052] It should be noted that, in the description of the present invention, terms such as "upper", "lower", "inside" and "outside" indicating directions or positional relationships are based on the directions or positional relationships shown in the drawings. This is only 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.

[0053] In addition, it should be noted that in the description of the present invention, unless otherwise clearly specified and limited, the terms "installation" and "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; it can be a direct connection, or it can be an indirect connection through an intermediate medium, or it can be the internal communication of two components. For those skilled in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0054] See also Figure 1 As shown, it is a step diagram of a forging process of an air suspension aluminum cylinder assembly according to an embodiment of the present invention. A forging process of an air suspension aluminum cylinder assembly according to the present invention comprises:

[0055] Step S100, placing a pre-forged blank in a forging die, and pre-forging the pre-forged blank, wherein the pre-forging includes controlling the forging die to forge the forging surface of the pre-forged blank;

[0056] Step S200, dividing the forging surface into a plurality of annular regions with equal annular widths, acquiring point cloud data of a plurality of points in each annular region during the pre-forging process in real time, and determining a characteristic coordinate value of each point based on the point cloud data;

[0057] Specifically, the width of the annular area can be determined by technicians in this field according to the forging accuracy requirements of the aluminum tube forging. The higher the forging accuracy requirements, the smaller the width of the annular area. Preferably, the width of the annular area can be 3 cm.

[0058] Specifically, the present invention does not limit the method of acquiring point cloud data. Preferably, a laser scanner can be used to emit a laser beam to the forging surface, and the distance information of each point on the forging surface can be calculated based on the time or phase difference of laser reflection. At the same time, combined with the built-in positioning system of the scanner, a three-dimensional coordinate system is established in the three-dimensional space and the position coordinates of each point are determined, which will not be repeated here.

[0059] Step S300, terminating the pre-forging and screening the uplift characterization area based on the change of characteristic coordinate values ​​of several points in each annular area, and determining whether the shape change of the pre-forged billet is abnormal according to the distribution of characteristic points in the uplift characterization area;

[0060] Wherein, the characteristic points are determined according to the characteristic coordinate values ​​of each point;

[0061] Step S400, forging the pre-forged billet with abnormal shape change in a forging compensation manner to obtain a forged part;

[0062] The forging compensation method includes determining the deformation category of the pre-forging billet according to the duration of the pre-forging process, and selecting and adjusting the holding time of the forging die according to the deformation category of the pre-forging billet, or setting a number of forging pause points during the forging process;

[0063] The adjustment amount of the holding time and the number of times the forging pause points are set are determined according to the outer contour parameters of the forged reference part, and the outer contour parameters are determined based on the height and width of the outer step;

[0064] In implementation, the forged reference part is the final air suspension aluminum tube forging part, and the outer contour parameters of the forged reference part are determined according to the size parameters of the final air suspension aluminum tube forging part.

[0065] Step S500, annealing the forged part to obtain an aluminum cylinder forged part.

[0066] Specifically, see Figure 2 As shown, it is a step diagram of determining the characteristic coordinate value of each point in an embodiment of the present invention, and determining the characteristic coordinate value of each point includes:

[0067] Step S201, establishing a three-dimensional rectangular coordinate system with the midpoint of the forging surface as the coordinate origin;

[0068] Step S202, obtaining the three-dimensional rectangular coordinates of a number of points in each annular area;

[0069] Step S203, determining the coordinate values ​​perpendicular to the forging surface direction in the three-dimensional rectangular coordinates as the characteristic coordinate values ​​of each point.

[0070] Specifically, the process of terminating the pre-forging and screening the ridge characterization area includes:

[0071] If the average value of the characteristic coordinate values ​​of several points in the annular region meets the explicit condition of forging surface bulge, the pre-forging is terminated and the annular region is selected as a bulge characterization region;

[0072] If the average value of the characteristic coordinate values ​​of several points in the annular region does not meet the explicit condition of forging surface bulge, the pre-forging will not be terminated and the annular region will not be screened.

[0073] The dominant condition for the forging surface bulge is that the average value of the characteristic coordinate value exceeds a preset characteristic coordinate reference value.

[0074] Specifically, the preset characteristic coordinate reference value can be determined by those skilled in the art based on the average value of historical data of several experimental data of forgings with the same specifications. Preferably, the characteristic coordinate reference value can be 0.3 cm.

[0075] Specifically, the present invention terminates pre-forging and screens the bulge characterization area by the change of characteristic coordinate values ​​of several points in each annular area. It can be understood that when the metal billet is pre-forged, the internal stress concentration of the metal will cause bulges to appear at the forging position, and the points in the bulge area will obviously rise in the direction perpendicular to the forging surface. During the pre-forging process, these obviously rising positions can provide scientific data support for the subsequent judgment of whether the shape change of the pre-forged billet is abnormal, and help to take targeted measures to adjust the forging process, correct shape abnormalities, and ensure product quality. The present invention terminates pre-forging and screens the bulge characterization area by the change of characteristic coordinate values ​​of several points in each annular area, thereby achieving the acquisition of several points with data representation during the pre-forging process, thereby improving the shape and size accuracy and performance consistency of the special-shaped aluminum tube forgings of the air suspension.

[0076] Specifically, the process of determining the characteristic points in the uplift characterization area includes:

[0077] Calculate the average value of characteristic coordinate values ​​of a plurality of points in the uplift characterization area;

[0078] Points whose characteristic coordinate values ​​of several points in the ridge characterization area exceed the average value are determined as the characteristic points.

[0079] Specifically, the process of determining whether the shape change of the pre-forged billet is abnormal includes:

[0080] Taking the midpoint of the forging surface as the center of the circle, the ridge characterization area is divided into a plurality of ridge characterization sector ring areas at a preset center angle;

[0081] Obtain the number of characteristic points in each ridge representation sector ring area;

[0082] If the number of characteristic points in each bulge characterization sector ring region does not meet the normal bulge characterization condition, it is determined that the shape change of the pre-forged billet is abnormal;

[0083] If the number of characteristic points in each bulge characterization sector ring region meets the normal bulge characterization condition, it is determined that the shape change of the pre-forged billet is normal;

[0084] The normal condition for uplift characterization is that the difference between the number of characteristic points in each uplift characterization sector ring region and the number of characteristic points in the remaining uplift characterization sector ring regions does not exceed a preset difference threshold.

[0085] Specifically, the preset center angle can be determined by technicians in this field according to the forging accuracy requirements of the aluminum cylinder forging. The higher the forging accuracy requirements, the smaller the preset center angle. Preferably, the preset center angle can be 30°.

[0086] Specifically, the preset difference threshold can be determined by a technician in this field based on the average value of the difference between the number of feature points in each uplift characterization fan ring area and the number of feature points in the remaining uplift characterization fan ring areas in several historical experiments under the condition that the uplift characterization fan ring area is divided by the same preset central angle. Preferably, when the central angle is 30°, the difference threshold can be 10% of the total number of points in the fan ring area.

[0087] Specifically, the present invention determines whether the shape change of the pre-forged billet is abnormal through the distribution of characteristic points in the uplift characterization area. It can be understood that the characteristic points represent the positions where the shape changes are more obvious in the uplift characterization area. The number of characteristic points in each uplift characterization fan ring area is obtained, and the degree of shape change in each sub-area can be expressed from the perspective of quantity, thereby characterizing whether the uplift phenomenon of the uplift characterization area as a whole is uniform. If the number of characteristic points in each uplift characterization fan ring area is significantly different from the number of characteristic points in the remaining uplift characterization fan ring areas, then the uplift phenomenon of the uplift characterization area as a whole is uneven. The present invention determines whether the shape change of the pre-forged billet is abnormal through the distribution of characteristic points in the uplift characterization area, thereby realizing the analysis of the forming shape stability of the special-shaped forgings according to the local deformation state of the material during the forging process, thereby improving the shape and size accuracy and performance consistency of the special-shaped aluminum cylinder forgings of the air suspension.

[0088] Specifically, the process of determining the deformation category of the pre-forged billet includes:

[0089] If the pre-forged billet with abnormal shape change meets the first abnormal category condition, the deformation category of the pre-forged billet is determined to be the first deformation abnormal category;

[0090] If the pre-forged billet with abnormal shape change does not meet the first abnormal category condition, the deformation category of the pre-forged billet is determined to be the second deformation abnormal category.

[0091] Specifically, the first abnormal category condition is that the duration of the pre-forging process does not exceed a preset duration reference value.

[0092] Specifically, the preset duration reference value may be determined by a technician in this field based on the average duration of the pre-forging process in several historical experiments of forging forgings of the same specifications. Preferably, the duration reference value may be 3s.

[0093] Specifically, the present invention determines the deformation category of the pre-forged billet by the duration of the pre-forging process. It can be understood that during the pre-forging process, there is a stress difference inside the pre-forging billet. For metals with poor fluidity, the internal stress balance process is relatively slow. Due to the poor fluidity, the forging die needs to forge the forging surface of the pre-forged billet for a longer period of time before the deformation of the forging surface reaches a data-representative deformation. Therefore, the internal fluidity difference of the material itself can be judged according to the difference in the speed of change of the bulge deformation amount of the forging surface of the forging during the forging process. The present invention determines the deformation category of the pre-forging billet by the duration of the pre-forging process, and further realizes the adaptive adjustment of the forging method according to the difference in material state, thereby improving the shape and size accuracy and performance consistency of the special-shaped aluminum tube forgings of the air suspension.

[0094] Specifically, see Figure 3 As shown, it is a logic flow chart of selecting an adjustment method for forging a pre-forged billet according to an embodiment of the present invention. The forging compensation method for the pre-forged billet includes:

[0095] If the deformation category of the pre-forged blank is the first abnormal deformation category, a forging compensation method for the pre-forged blank is selected to set a number of forging pause points during the forging process according to the outer contour parameters of the forging reference piece;

[0096] If the deformation category of the pre-forged billet is the second abnormal deformation category, the forging compensation method selected for the pre-forged billet is to adjust the holding time of the forging die according to the outer contour parameters of the forging reference part.

[0097] Specifically, under the condition that the deformation category of the preforged billet is the first deformation abnormality category, the present invention selects a forging compensation method for the preforged billet as setting a number of forging pause points during the forging process of the preforged billet. It can be understood that when the preforged billet is the first deformation abnormality category, the fluidity of the preforged billet is better, and the flow speed of the preforged billet is relatively fast during the preforging process. In this case, the stress distribution inside the preforged billet also changes relatively rapidly. In the pause gap of the forging pause point, the stress inside the preforged billet will be adjusted through the elasticity and plastic deformation of the preforged billet itself. By setting multiple forging pause points, the stress distribution can be adjusted multiple times during the entire preforging process. Each pause provides an opportunity for the preforged billet to relax stress, and then, the forging method is adaptively adjusted according to the difference in material state, thereby improving the shape and size accuracy and performance consistency of the special-shaped aluminum cylinder forgings of the air suspension.

[0098] Specifically, the adjustment amount of the holding time is positively correlated with the outer contour parameter, and the setting number of the forging pause point is positively correlated with the outer contour parameter.

[0099] Specifically, the forging die applies pressure to the pre-forged billet so that the pre-forged billet fills the forging die, and the forging pressure is maintained for a period of time. The duration of the pressure maintenance is the pressure holding time. This is the prior art and will not be described in detail here.

[0100] Specifically, see Figure 4 As shown, it is a schematic diagram of the height and width of the surface step of the forged reference part according to an embodiment of the present invention, and the surface contour parameter is the ratio of the height h to the width w of the surface step.

[0101] Specifically, under the condition that the deformation category of the preforged billet is the second abnormal deformation category, the present invention selects a forging compensation method for the preforged billet as adjusting the holding time of the forging die according to the external contour parameters of the forging reference part. It can be understood that when the preforged billet is the second abnormal deformation category, the deformation of the preforged billet under pressure is relatively difficult due to the internal organizational structure of the preforged billet, and a certain amount of time and continuous pressure are required to achieve the expected deformation amount. The external contour parameters of the forging reference part can characterize the degree of deformation of the special-shaped part of the forging part, and the height and width of the external step can characterize the degree of deformation of the special-shaped part of the forging part. The larger the ratio of degree, the greater the degree of deformation of the special-shaped part of the forging, which means that the pre-forged billet needs to overcome greater resistance at this position and more time is needed to complete the forging. Adjusting the holding time can make the forging process more precise. For forgings with a large degree of deformation in special-shaped parts, appropriately extending the holding time can allow the pre-forged billet enough time to deform in this complex shape area. Furthermore, the forging method is adaptively adjusted according to the difference in material state, which improves the shape and size accuracy and performance consistency of the special-shaped aluminum cylinder forgings of the air suspension.

[0102] 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.

[0103] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A forging process for an air suspension aluminum cylinder assembly, characterized in that: include: Placing a preforged blank in a forging die, and preforging the preforged blank, wherein the preforging comprises controlling the forging die to forge a forging surface of the preforged blank; The forging surface is divided into a plurality of annular regions with equal annular widths, point cloud data of a plurality of points in each annular region during the pre-forging process are acquired in real time, and characteristic coordinate values ​​of each point are determined based on the point cloud data; Based on the change of characteristic coordinate values ​​of several points in each annular area, the pre-forging is terminated and the uplift characterization area is screened, and whether the shape change of the pre-forged blank is abnormal is determined according to the distribution of characteristic points in the uplift characterization area; Wherein, the characteristic points are determined according to the characteristic coordinate values ​​of each point; Forging the pre-forged billet with abnormal shape change in a forging compensation manner to obtain a forged part; The forging compensation method includes determining the deformation category of the pre-forging billet according to the duration of the pre-forging process, and selecting and adjusting the holding time of the forging die according to the deformation category of the pre-forging billet, or setting a number of forging pause points during the forging process; The adjustment amount of the holding time and the number of times the forging pause points are set are determined according to the outer contour parameters of the forged reference part, and the outer contour parameters are determined based on the height and width of the outer step; The forged part is annealed to obtain an aluminum cylinder forged part.

2. The forging process of the air suspension aluminum cylinder assembly according to claim 1, characterized in that: Determine the characteristic coordinate values ​​of each point including: Taking the midpoint of the forging surface as the coordinate origin, a three-dimensional rectangular coordinate system is established; Obtain the three-dimensional rectangular coordinates of several points in each annular area; The coordinate values ​​perpendicular to the forging surface direction in the three-dimensional rectangular coordinates are determined as the characteristic coordinate values ​​of each point.

3. The forging process of the air suspension aluminum cylinder assembly according to claim 2, characterized in that: The process of terminating the pre-forging and screening the ridge characterization area includes: If the average value of the characteristic coordinate values ​​of several points in the annular region meets the explicit condition of forging surface bulge, the pre-forging is terminated and the annular region is selected as a bulge characterization region; The dominant condition for the forging surface bulge is that the average value of the characteristic coordinate value exceeds a preset characteristic coordinate reference value.

4. The forging process of the air suspension aluminum cylinder assembly according to claim 3, characterized in that: The process of determining the characteristic points in the uplift characterization area includes: Calculate the average value of characteristic coordinate values ​​of a plurality of points in the uplift characterization area; Points whose characteristic coordinate values ​​of several points in the ridge characterization area exceed the average value are determined as the characteristic points.

5. The forging process of the air suspension aluminum cylinder assembly according to claim 4, characterized in that: The process of determining whether the shape change of the pre-forged blank is abnormal includes: Taking the midpoint of the forging surface as the center of the circle, the ridge characterization area is divided into a plurality of ridge characterization sector ring areas at a preset center angle; Obtain the number of characteristic points in each ridge representation sector ring area; If the number of characteristic points in each bulge characterization sector ring region does not meet the normal bulge characterization condition, it is determined that the shape change of the pre-forged billet is abnormal; The normal condition for uplift characterization is that the difference between the number of characteristic points in each uplift characterization sector ring region and the number of characteristic points in the remaining uplift characterization sector ring regions does not exceed a preset difference threshold.

6. The forging process of the air suspension aluminum cylinder assembly according to claim 5, characterized in that: The process of determining the deformation category of the pre-forged billet includes: If the pre-forged billet with abnormal shape change meets the first abnormal category condition, the deformation category of the pre-forged billet is determined to be the first deformation abnormal category; If the pre-forged billet with abnormal shape change does not meet the first abnormal category condition, the deformation category of the pre-forged billet is determined to be the second deformation abnormal category.

7. The forging process of the air suspension aluminum cylinder assembly according to claim 6, characterized in that: The first abnormal category condition is that the duration of the pre-forging process does not exceed a preset duration reference value.

8. The forging process of the air suspension aluminum cylinder assembly according to claim 7, characterized in that: The forging compensation method for the pre-forged billet includes: If the deformation category of the pre-forged blank is the first abnormal deformation category, a forging compensation method for the pre-forged blank is selected to set a number of forging pause points during the forging process according to the outer contour parameters of the forging reference piece; If the deformation category of the pre-forged billet is the second abnormal deformation category, the forging compensation method selected for the pre-forged billet is to adjust the holding time of the forging die according to the outer contour parameters of the forging reference part.

9. The forging process of the air suspension aluminum cylinder assembly according to claim 8, characterized in that: The adjustment amount of the holding pressure time is positively correlated with the outer contour parameter, and the setting number of the forging pause point is positively correlated with the outer contour parameter.

10. The forging process of the air suspension aluminum cylinder assembly according to claim 9, characterized in that: The outer contour parameter is the ratio of the height to the width of the outer step.

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