Segmented welding method for welding an aeroengine assembly

Abstract

The present invention discloses a segmented welding method for aero-engine welding components. Specifically, the method involves determining a model, including: fabricating a test piece, obtaining original welding parameters, arbitrarily selecting a weld point P0 on the weld, determining a first volume V0, and selecting a weld point Px on the weld with a thickness T. X Take the J1*T in front of the weld pool of the Px solder joint. X The length of the first volume V0 is used to determine the second volume Vx, and the model is determined based on the second volume Vx and the first volume V0. The initial weld point Pz0 and the adjacent weld point Pz1 of the weld seam of the part are determined. The original parameters and mathematical model obtained by the test piece are used to determine the welding voltage, current and speed. The first and second parameters are input into the programming software to control the CNC welding machine to complete the welding between the parts. It can ensure the consistency of weld formation and improve the welding quality under the condition of changes in weld cross-section and thickness.

Description

Technical Field

[0001] This invention belongs to the field of welding process technology, and particularly relates to a method for segmented welding of aero-engine welding components. Background Technology

[0002] In the welding and processing of aerospace parts, test pieces are used to conduct welding process tests. After a qualified weld is welded on the test piece, the part is then welded. The drawback is that aerospace parts generally have a complex structure, and the heat dissipation conditions of the part and the test piece are not the same, resulting in differences between the weld and the test piece.

[0003] In this situation, the greater the difference in heat dissipation conditions, the greater the difference between the weld of the test piece and the weld of the part, and they may even be completely different. For example, if the heat dissipation of the part is better than that of the test piece, it is easy to cause the weld to be narrower, the penetration depth to be less, or the weld to be incomplete. Conversely, it may cause the weld to be too wide or the weld to be leaky. Moreover, when the heat dissipation conditions on both sides of the entire weld of the component change too much, it is also easy to cause uneven formation of the single weld, resulting in unqualified welds and low overall processing efficiency.

[0004] In view of this, the present invention is hereby proposed. Summary of the Invention

[0005] The purpose of this invention is to provide a segmented welding method for aero-engine welding components, solving the technical problem of low processing efficiency in traditional welding methods. The technical solution of this invention has many beneficial effects, as described below:

[0006] A method for segmented welding of aero-engine welding components is provided, comprising welding between parts, the method including:

[0007] The model is determined by: fabricating a test piece with a weld seam; randomly selecting a weld point P0 on the weld seam; and obtaining the thickness T0 of weld point P0, the length J1*T0 in front of the molten pool of weld point P0, and the length J2*T0 of the weld seam normal, to determine a first volume V0, where the first volume V0 = J1*J2*T0. 3 ;

[0008] Take a weld point Px on the weld, with a thickness of T. X Take the J1*T in front of the weld pool of the Px solder joint. X The length of the weld and the normal direction of J2*T X The length of the second volume Vx is determined by the fact that solder point Px is adjacent to solder point P0, and J1 and J2 are rational numbers.

[0009] The model is determined based on the second volume Vx and the first volume V0;

[0010] The initial weld point Pz0 of the weld seam of the part is determined. The first parameter of the initial weld point Pz0 is determined by the model. The first parameter includes the welding voltage, current and speed.

[0011] A weld point Pz1 adjacent to the initial weld point Pz0 is determined on the weld seam of the part, and the second parameter of the weld point Pz1 is determined by the model;

[0012] The first and second parameters are input into the programming software to control the CNC welding machine to complete the welding of the seams between the parts.

[0013] Compared with the prior art, the technical solution provided by the present invention has the following beneficial effects:

[0014] By calculating the thickness and volume change rates along the weld direction and then performing coupled calculations, the welding energy change is obtained, thereby changing the welding parameters to ensure good weld formation and uniformity. This allows for precise control of welding parameters based on changes in thickness and cross-section, improving the overall welding quality of product parts and ensuring the controllability and consistency of product forming. Attached Figure Description

[0015] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0016] Figure 1 This is a schematic diagram showing the weld formed after welding test pieces A and B.

[0017] Figure 2 This is a front view of the parts to be welded;

[0018] Figure 3 Take a semi-circular section view of the weld seam of the part;

[0019] Figure 4 The cross-section at the Pz0 spot weld location of part;

[0020] Figure 5 This is the cross-section of the spot weld location on part Pz1;

[0021] Figure 6 A schematic diagram of the volume change curve calculated for heat dissipation during welding of the part;

[0022] Figure 7 This is a schematic diagram of the welding current variation curve for the component. Detailed Implementation

[0023] The following specific examples illustrate the implementation of the present invention. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of them. The present invention can also be implemented or applied through other different specific embodiments, and the details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of the present invention. It should be noted that, in the absence of conflict, the following embodiments and features in the embodiments can be combined with each other. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0024] It should be noted that various aspects of embodiments within the scope of the appended claims are described below. It will be apparent that the aspects described herein can be embodied in a wide variety of forms, and any particular structure and / or function described herein is merely illustrative. Based on this invention, those skilled in the art will understand that one aspect described herein can be implemented independently of any other aspect, and two or more of these aspects can be combined in various ways. For example, any number of aspects set forth herein can be used to implement the device and / or practice the method. Additionally, this device and / or method can be implemented using structures and / or functionalities other than one or more of the aspects set forth herein.

[0025] It should also be noted that the illustrations provided in the following embodiments are only schematic representations of the basic concept of the present invention. The drawings only show the components related to the present invention and are not drawn according to the actual number, shape and size of the components in the actual implementation. In the actual implementation, the form, quantity and proportion of each component can be arbitrarily changed, and the layout of the components may also be more complex.

[0026] Furthermore, specific details are provided in the following description to facilitate a thorough understanding of the examples. However, those skilled in the art will understand that aspects can be practiced without these specific details. To enable those skilled in the art to better understand the invention, the invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. The terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, features defined as "first" and "second" may explicitly or implicitly include one or more of that feature. In the description of the invention, unless otherwise stated, "a plurality of" means two or more.

[0027] The segmented welding method for aero-engine welding components of the present invention is described in the following document: Figure 4 and Figure 5The variation in the weld seam primarily addresses the issue of poor weld formation caused by inconsistent thickness and heat dissipation conditions at different locations along the weld seam during the welding of butt joints between parts. By calculating the rate of change in weld thickness and volume along the weld direction, and then performing coupled calculations, the change in welding energy is derived. During the machine welding process, welding parameters are continuously adjusted to ensure good weld formation and uniformity throughout the entire weld seam. This achieves the goal of precisely controlling welding parameters based on changes in thickness and cross-section. The methods include:

[0028] S101: Determine the model, including: fabricating a test piece similar to a local cross-section of the part, obtaining the original welding parameters, and setting weld seams on the test piece. See [link / reference]. Figure 1 The diagram shown below illustrates the welded joint 3 formed by specimen A 1 and specimen B 2.

[0029] Take any weld point P0 on weld 3, and obtain the thickness T0 of weld point P0, the length J1*T0 in front of the molten pool of weld point P0, and the length J2*T0 in the normal direction of weld 3 to determine the first volume V0. The first volume V0 = J1*J2*T0 3 Take another weld point Px on the weld seam, with a thickness of T. X Take the solder joint Px and the J1*T in front of the molten pool. X The length of the weld and the normal direction of J2*T X The length of the weld is such that weld point Px is adjacent to weld point P0, to determine the second volume Vx. J1 and J2 are rational numbers. Generally, the range of J1 and J2 is (2-15). If it is too large, it will be impossible to accurately calculate and control the weld. It should be noted that the material of the parts is generally a high-temperature alloy. The values ​​of constants J1 and J2 can be appropriately adjusted according to the specific material in the actual application. Taking stainless steel as an example, J1=2 and J2=5. The length on both sides of the normal direction is 2T. Take a 100mm (length) * 60mm (width) * 5mm (thickness) test piece for butt welding. The first volume V0 = 2T0 * 5T0 * T0 = 10T0 3 =10*5 3 mm 3 =750mm 3 The second volume is calculated in the same way.

[0030] S102: Determine the model based on the second volume Vx and the first volume V0, specifically:

[0031] 1) Determine the change in heat dissipation energy ΔE a ,in:

[0032] The rate of change of the welding heat dissipation volume relative to the initial position P0 is (V x -V0) / V0, then the energy change at the second volume position relative to the first volume position on the weld is K1*(V x-V0)*E0 / V0, where: K1 is the volumetric material constant; energy AC represents the initial voltage; BC represents the initial current; SP represents the initial welding speed, which can be obtained through existing orthogonal experimental methods.

[0033] Change in heat dissipation energy ΔE a =10%*(V X -V0)*E0 / V0; that is, K1 is 10%.

[0034] The model is determined based on the changes in heat dissipation energy.

[0035] 2) Determine the relationship between welding energy and thickness variation ΔE b ,in:

[0036] Considering that weld thickness is the main factor affecting weld formation, experiments show that when the weld thickness changes, for every 1mm change in thickness, the energy change E of thickness T0 is K2*E0 / T0 (the energy of the entire weld thickness is converted into energy per unit thickness). K2, at 16%, is the material constant for the thickness of stainless steel and high-temperature alloys. For other materials, the value of K2 can be adjusted appropriately to check accuracy. That is, for a 1mm increase in thickness, the energy change is +16%*E0 / T0; for a 1mm decrease in thickness, the energy change is -16%*E0 / T0. For every ΔT mm change in thickness, the energy change is 16%*ΔT*E0 / T0 = 16%*(T). X -T0)*E0 / T0;

[0037] Therefore, we can conclude that:

[0038] ΔE b =K2*(T X -T0)*E0 / T0;

[0039] In actual welding, considering both heat dissipation and thickness variations, the energy change is the sum of both, therefore the total energy change ΔE = ΔE a +ΔE b , represented as:

[0040] K1*(V X -V0)*E0 / V0+K2*(T X -T0)*E0 / T0;

[0041] 3) Determine the model based on the total energy change, and the energy value E of solder joint Px. X Represented as:

[0042] E X =E0+ΔE=E0+K1*(V X -V0)*E0 / V0+K2*(T X -T0)*E0 / T0;

[0043] according to Where ACx is the voltage at solder joint Px; BCx is the current at solder joint Px; and SPx is the welding speed at solder joint Px. The formula can be modified to obtain:

[0044]

[0045] It is used as the final model.

[0046] Furthermore, for the convenience of actual control, it is generally necessary to select a single variable for actual control, such as voltage ACx, current BCx, or welding speed SPx as a single control variable factor. Preferably, current is selected as the single control factor of the model.

[0047] S103: Determine the initial weld point Pz0 of the part weld. The first parameter of the initial weld point Pz0 is determined by the model, including the welding voltage, current, and speed. Also, determine the weld point Pz1 adjacent to the initial weld point Pz0 on the part weld. The second parameter of weld point Pz1 is determined by the model. Specifically, the initial weld point Pz0 of the part weld is determined as follows:

[0048] See Figure 2 Welding joint 6 is made between part A 4 and part B 5. The thickness of the weld joint is Tz, and the maximum thickness is 3.5mm. The material of the part is titanium alloy TC4, and the thickness Tz is a variable value. Rational numbers J1 and J2 are selected to ensure the accuracy of the welding heat dissipation calculation. The set A of all cross-sectional areas of the weld joint is determined.

[0049] Calculate the area S of the cross section where the solder joint P0 of the test piece is located: S = 2 * J1 * T0 * T0;

[0050] For each data point in set A, calculate the difference between it and the area S, and then take the absolute value of the difference.

[0051] like Figure 4 As shown, the thickness point in the cross-sectional area corresponding to the minimum absolute value is determined as the initial weld point Pz0;

[0052] The voltage AC0, current BC0, and welding speed SP0 corresponding to the initial weld point Pz0 are obtained using orthogonal experimental design and input into the model as the first parameters. Then, CAD-aided software is used to calculate the heat dissipation volume and thickness variation at any point on the weld, thereby obtaining parameters such as current, voltage, and welding speed at any point. A welding program can then be generated. Figure 5 As shown, then arbitrarily select a solder point Pz1 adjacent to the initial solder point Pz0 (it can be the end point, the midpoint, or other points). Using the model determined above, the second parameter of solder point Pz1 is obtained.

[0053] S104: See also Figure 3 As shown, the first and second parameters are input into the programming software to control the CNC welding machine to complete the welding of parts. Preferably, the CNC welding machine is equipped with a UG programmable program, which can automatically generate the volume change curve on the weld seam of the part and obtain the heat dissipation calculation curve at any position. To make the calculation more convenient and efficient, the CAD auxiliary software can be further developed to define the weld seam curve, J1, J2, K1, K2, and the initial test piece parameters AC0, BC0, SP0. The sampling point spacing or precision can also be defined. Finally, the heat dissipation calculation volume data at any point is obtained, and after exporting, the heat dissipation calculation volume change curve is plotted, such as... Figure 6 This step is optional; the curve can be used for analysis.

[0054] Furthermore, for ease of practical control, welding control is generally performed using current as the variable, thereby obtaining current data at any point and plotting curves as shown. Figure 7 As shown. Based on the obtained welding parameters and point data, a welding program is created. When welding parts, the actual Pz0 position of the part is aligned with the calculated Pz0 position, and the welding direction is consistent, thus completing the welding.

[0055] This method is suitable for adaptive parameter trajectory planning schemes with complex part structures and uneven heat dissipation conditions, and can be applied to data analysis and extraction as well as CAD-aided software development.

[0056] The product provided by this invention has been described in detail above. Specific examples have been used to illustrate the principles and implementation methods of this invention. The descriptions of the embodiments above are merely for the purpose of helping to understand the core ideas of this invention. It should be noted that those skilled in the art can make various improvements and modifications to the invention without departing from the principles of the invention, and these improvements and modifications also fall within the protection scope of the invention claims.

Claims

1. A segmented welding method for aero-engine welding components, applicable to welding between parts, characterized in that, The methods include: The model is determined by: fabricating a test piece with a weld seam; randomly selecting a weld point P0 on the weld seam; and obtaining the thickness T0 of weld point P0 and the area J1 in front of the molten pool of weld point P0. The length of T0 and the weld normal J2 The length of T0 is used to determine the first volume V0, where the first volume V0 = J1. J2 T0 3 ; Take a weld point Px on the weld, with a thickness of T. X Take the weld pool front of the Px weld at J1 T X The length of the weld and the normal direction of J2 T X The length of the second volume Vx is determined by the fact that solder point Px is adjacent to solder point P0, and J1 and J2 are rational numbers. The model is determined based on the second volume Vx and the first volume V0; The initial weld point Pz0 of the weld seam of the part is determined. The first parameter of the initial weld point Pz0 is determined by the model. The first parameter includes the welding voltage, current and speed. A weld point Pz1 adjacent to the initial weld point Pz0 is determined on the weld seam of the part, and the second parameter of the weld point Pz1 is determined by the model; The first and second parameters are input into the programming software to control the CNC welding machine to complete the welding of the seams between the parts. Determining the model based on the second volume Vx and the first volume V0 includes: Determine the change in heat dissipation energy ΔE a ,in: The rate of change of the welding heat dissipation volume relative to the initial position P0 is (V x -V0) / V0, then the energy change at the second volume position relative to the first volume position on the weld is K1 (V) x -V0) E0 / V0, where: K1 is the volumetric material constant; energy E0 AC represents the initial voltage; BC represents the initial current; SP represents the initial welding speed. Change in heat dissipation energy ΔE a =10% (V) X -V0) E0 / V0, where K1 is 10%; The model is determined based on the change in heat dissipation energy, including determining the relationship between welding energy and thickness change ΔE. b ,in: The energy change E of thickness T0 is K2 E0 / T0, K2 is the material constant for thickness. The energy change for each thickness change of ΔT mm is expressed as: K2 ΔT E0 / T0=K2 (T X -T0) E0 / T0; We can obtain: ΔE b =K2 (T X -T0) E0 / T0; When considering both heat dissipation and thickness variations, the total energy change is ΔE = ΔE. a +ΔE b , is represented as: K1 (V X -V0) E0 / V0+K2 (T X -T0) E0 / T0; The model is determined based on the total energy change.

2. The segmented welding method for aero-engine welding components according to claim 1, characterized in that, The range of rational numbers J1 and J2 is 2-15.

3. The segmented welding method for aero-engine welding components according to claim 1, characterized in that, K2 is 16%.

4. The segmented welding method for aero-engine welding components according to claim 1, characterized in that, Determine the initial weld point Pz0 of the weld seam of the part, including: Let the thickness of the weld seam of the part be Tz, and let the thickness Tz be a variable value. Then select rational numbers J1 and J2, and then determine the set A of all cross-sectional areas of the weld seam of the part. Calculate the area S = 2 of the cross section where the solder joint P0 of the test piece is located. J1 T0 T0; For each data point in set A, calculate the difference between it and the area S, and take the absolute value of the difference. The thickness point in the cross-sectional area corresponding to the minimum absolute value is taken as the initial weld point Pz0; The voltage AC0, current BC0, and welding speed SP0 corresponding to the initial weld point Pz0 are obtained and input into the model. Then, with the help of CAD-aided software, the heat dissipation volume and thickness change at any point on the weld are obtained, thereby obtaining the current, voltage, and welding speed parameters at any point, which can generate a welding program.

5. The segmented welding method for aero-engine welding components according to claim 4, characterized in that, It is used in programmable CNC welding machines.

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