A method and system for combined bending and forming of a catheter

Abstract

The application relates to the field of advanced manufacturing technology of metal complex components, and discloses a combined bending forming method and system of a pipe, the combined bending forming method continuously carries out numerical control bending processing on a pipe blank with a certain length to obtain two or more bent pipe parts, and finally, the parts obtained through continuous bending processing are cut based on cutting lines, and finally, the parts are divided into single pipe parts. The method can obviously reduce material loss, save cost, ensure pipe bending quality, improve processing efficiency, meet the use requirements in the production process, further optimize the numerical control bending pipe processing process, and can realize batch pipe low-cost and short-time quality guarantee production.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of advanced manufacturing technology of metal complex components, in particular to a combined bending forming method and system of a pipe. BACKGROUND

[0002] At present, the numerical control pipe precise forming technology realizes the precise forming of the pipe and the automation of the production process, and also meets the high-precision and high-efficiency processing requirements of pipe bending. Therefore, the numerical control pipe bending technology has occupied an important position in the high-tech field of aerospace. The traditional numerical control pipe bending method mainly adopts single-piece numerical control bending, that is, one pipe is processed into one product. Since the numerical control pipe bender needs to clamp the pipe during processing, a process clamping allowance of 300-800 mm needs to be reserved on the basis of the unfolded raw material length of the part according to the pipe specifications when each pipe is bent and formed. This clamping allowance is generally not part of the product, resulting in a large amount of material waste. In addition, each numerical control pipe bending needs to complete the feeding and clamping operations, resulting in a long production cycle.

[0003] At present, relevant researches on numerical control pipe bending technology have been carried out at home and abroad, and the methods all adopt single-piece numerical control bending. For example, the invention patent with publication number CN106354919A discloses a digital precise forming method for flared pipe sampling. According to the product design assembly requirements, based on finite element simulation, the pipe model that meets the installation requirements and can be numerically controlled is obtained for numerical control bending, solving the problems of "repeated bending" and "string bending" existing in on-site pipe sampling and manual bending.

[0004] Further, Li Guangjun et al. (Luozhang, Yuan Sheng, Wei Zhanchong. Development and application of continuous multi-bend pipe forming simulation system [J] Aviation Manufacturing Technology, 2018, 61(18): 43-47) proposed a pipe bending forming simulation system based on CATIA environment to meet the demand of digital precise forming of space continuous multi-bend pipe, realizing the forming simulation analysis of space continuous multi-bend pipe.

[0005] However, the numerical control bending methods of the above-mentioned researches all adopt traditional single-piece numerical control bending, which has the problems of material waste and long production cycle. SUMMARY

[0006] In order to solve the problems and deficiencies in the prior art, the present application proposes a combined bending forming method and system of a pipe. This method can significantly reduce the loss of raw materials, save costs, ensure the bending quality of the pipe, improve the processing efficiency, meet the use requirements in the production process, further optimize the numerical control pipe bending process, and realize low-cost and short-time quality production of batch pipes.

[0007] In order to achieve the above-mentioned application purposes, the technical solutions of the present application are as follows:

[0008] A method for bending and shaping a conduit assembly includes the following steps:

[0009] S1. Extract basic information of the conduit part to be bent: Extract the conduit material grade, conduit specifications and bending radius from the digit model of the part to be bent.

[0010] S2. Based on the "three similarities" principle, preliminarily determine the conduit parts that can be combined and bent, and determine the CNC bending equipment: To ensure that the mold is not changed during the bending process, the combined bending conduit parts must meet the "three similarities" principle, namely, the same conduit material grade, the same conduit specifications, and the same bending radius. Therefore, based on the basic information of the parts extracted in step S1, conduit parts that meet the combined bending conditions are screened out. At the same time, based on the specifications of the screened conduit parts that can be combined and bent, the corresponding CNC bending forming equipment is selected, and the final conduit unfolded length limit L is obtained based on the CNC bending forming equipment. 设备max and catheter clamping process allowance L 夹持 .

[0011] In this invention, the limit of the catheter deployment length L 设备max and catheter clamping process allowance L 夹持 It is related to the CNC bending and forming equipment. Once the CNC bending and forming equipment is selected, its guide tube unfolding limit and guide tube clamping allowance are determined.

[0012] S3. Based on the initially selected combinable and bendable conduit parts and the CNC bending equipment, the final combinable and bendable conduit parts are determined, and the CNC bending machining parameters are obtained based on the final determined combinable and bendable conduit parts: the spatial coordinates of the conduit parts initially selected in step S2 are extracted, and then converted into machining parameters for the CNC machine tool. The machining parameters include the straight segment length L. if Bending rotation angle R if and bending angle A if Where i is the part number, f is the f-th bending segment of part i, and then the centerline unfolded length L of each conduit part is calculated according to the processing parameters. i And the unfolded length L of the assembled conduit; among the initially selected conduit components that can be combined and bent, the final conduit components that can be combined and bent are determined, that is, the unfolded length L of the assembled conduit components should not exceed the conduit unfolded length limit L. 设备max Finally, the CNC bending machining parameters are obtained based on the final determined conduit parts that can be combined and bent.

[0013] L = L 夹持 +L1+L 1工艺 ++L2+L 2工艺 +......+L i +Li工艺 ≤L 设备max ;

[0014] Wherein, L i工艺 is the process allowance required according to the part demand;

[0015] Conduit part bending data:

[0016]

[0017]

[0018] In the present application, the conduit part space coordinates can be directly read in three-dimensional modeling software. Based on CATIA and other three-dimensional modeling software, the part space coordinate values can be directly read through the modeling software, and then the relationship between the part space coordinates and the bending data of the machine tool is utilized to convert it through mathematical calculation.

[0019] S4. Based on the numerical control bending equipment machining parameters determined in step S3, the combined bending data of the conduit part is designed: the combined bending data of the conduit part selected in step S3 is designed, and the key of combination is the bending data design of the adjacent conduit connecting end. The design method is to combine the adjacent conduit connecting position into a straight line segment, and adjust the rotation angle α at the connecting position, as shown in the following table. The requirement is that the length of the combined intermediate straight line segment of the connecting position meets the minimum intermediate straight line segment length requirement of the numerical control machine tool for the bent pipe, the rotation angle α is a variable, the initial value is 180, which can be decreased according to the set gradient, the value range is 0~±180°, in addition, α can be manually set according to experience The initial value of the connecting position straight line segment L can be combined. The combined bending data after design recommends the trend of the conduit at both ends of the connecting position as "Z" type, avoiding "U" type or closed loop type.

[0020] Combined bending data after design:

[0021]

[0022]

[0023] Wherein, L 1f +L 1工艺 +L 2工艺 +L 21 ≥ Equipment minimum intermediate straight line segment requirement for conduit

[0024] S5. The combined bending data of the pipe parts is shaped by simulation: interference simulation analysis of the combined bending data designed in step S4 is carried out by bending simulation software; if the combined pipe shaping process designed in step S4 interferes with the numerical control pipe bending machine, the simulation analysis is carried out again after the combined bending data is redesigned in step S4 until the parts are not interfered with the machine when they are shaped based on the combined bending data, and finally the qualified combined bending data of the pipe parts is output.

[0025] S6. Numerical control bending shaping of the parts based on the combined bending data: the parts are numerically controlled and bent according to the combined bending data output in step S5, and the numerical control shaping operation is processed according to the existing mature numerical control bending shaping operation steps.

[0026] S7. The shaped parts are measured and the corresponding cutting lines are drawn: the parts after combined bending shaping are measured by a vector measuring machine, and the end cutting lines are drawn on the parts.

[0027] In the present application, the end cutting line is generally located at the connection position of the pipe parts.

[0028] S8. Cutting the parts based on the cutting lines drawn, the parts are divided into several single pipe parts: the multiple combined bending pipes are roughly cut according to the marking position reserved in step S7, and the entire part is divided into several single pipe parts, and finally the end of the pipe part after rough cutting is flattened and chamfered.

[0029] S9. Product detection: the product after cutting in step S8 is tested by a vector measuring machine, and compared with the theoretical model of the product, if the pipe manufacturing error meets the design requirements, the product is determined to be qualified, and the product can be delivered, if it is not qualified, it is scrapped.

[0030] Based on the same inventive concept, the present application also provides a pipe combined bending shaping system, characterized in that the system is used to realize the pipe combined bending shaping method, and the system comprises a pipe part data extraction and conversion module, a pipe part combined bending scheme preliminary selection module, a combined bending shaping simulation and combined bending scheme optimization module and a combined bending shaping module; wherein,

[0031] The pipe part data extraction and conversion module is used to extract the basic information of the pipe parts to be bent, determine the combined bending pipe parts and the numerical control bending equipment according to the basic information, and finally convert the selected combined bending pipe parts to obtain the numerical control bending equipment processing parameters;

[0032] The pipe part combined bending scheme preliminary selection module is used to design the pipe part combined bending data according to the numerical control bending equipment processing parameters;

[0033] The combined bending forming simulation and combined bending scheme optimization module is configured to perform interference simulation analysis of the forming process based on the obtained combined bending data, and to perform optimization adjustment on the combined bending data according to the simulation analysis result.

[0034] The combined bending forming module is configured to perform combined bending numerical control forming on the part according to the combined bending data after the optimization adjustment.

[0035] The present application has the following advantages:

[0036] (1) The present application provides a catheter part combined bending scheme design and processing method for digital design catheter processing. The method saves the 300-800mm process clamping allowance required for single piece numerical control bending, significantly reduces the loss of raw materials, and saves production cost.

[0037] (2) In the bending forming, one catheter can bend multiple products at a time, reducing the number of operator loading and unloading, reducing the labor intensity of technical personnel, and significantly improving the bending efficiency of the catheter.

[0038] (3) After the bending data of multiple independent catheter parts is combined, only one numerical control bending forming process is required on the catheter raw material, and then simple single cutting is performed, so that the processing of multiple catheter parts can be completed. The present application processes multiple parts first and then processes them once. Compared with the traditional single processing, the present application can greatly save raw materials and significantly improve the processing efficiency. BRIEF DESCRIPTION OF DRAWINGS

[0039] The foregoing and subsequent specific description of the present application becomes clearer when read in conjunction with the following drawings, in which:

[0040] Figure 1 The present application is a catheter combined part processing flow chart;

[0041] Figures 2-5 The present application is a design scheme diagram of combined bending of catheter parts of the same specification type in the embodiment of the present application;

[0042] Figures 6-8 The present application is a design scheme diagram of combined bending of catheter parts of different specification types in the embodiment of the present application. DETAILED DESCRIPTION

[0043] In order for those skilled in the art to better understand the technical solutions in the present application, the following will further illustrate the technical solutions for achieving the purposes of the present application through several specific embodiments. It should be noted that the technical solutions claimed by the present application include but are not limited to the following embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor should fall within the scope of protection of the present application.

[0044] At present, the numerical control pipe precise forming technology realizes the precise forming of the pipe and the automation of the production process, and also meets the high-precision and high-efficiency processing requirements of pipe bending, so the numerical control pipe bending technology has occupied an important position in the high-tech field of aerospace. The traditional numerical control pipe bending method mainly adopts single-piece numerical control bending, that is, one pipe is processed into one product. Since the numerical control pipe bender needs to clamp the pipe during processing, a process clamping allowance of 300-800 mm needs to be reserved on the basis of the unfolded raw material length of the part according to the pipe specifications when each pipe is bent and formed. The clamping allowance is generally not part of the product, resulting in a large amount of material waste. In addition, each numerical control pipe bending needs to complete the feeding and clamping operations, resulting in a long production cycle.

[0045] Based on this, the embodiments of the present application propose a pipe combined bending forming method. When bending and forming, one pipe can be bent into multiple products at a time, saving the 300-800 mm process clamping allowance required for single-piece numerical control bending, significantly reducing the loss of raw materials, saving production costs, reducing the number of feeding and unloading operations of the operator, reducing the labor intensity of the operator, and significantly improving the bending efficiency of the pipe parts.

[0046] In order to better illustrate and explain the technical solutions of the present application, the embodiments of the present application are introduced based on the combined bending forming of two types of pipe parts, as follows.

[0047] Embodiment 1

[0048] Referring to the drawings in the specification Figures 2-5 , the present embodiment provides a combined bending forming processing method for pipe parts of the same type. The process flow includes the following steps:

[0049] S1. Extract the basic information of the pipe parts to be bent (the outer shape of the pipe parts is shown in the specification Figure 2 ): based on the CATIA three-dimensional surface system platform, extract the basic information of the numerical model of the pipe parts to be bent, including the pipe material grade, the pipe specification, and the bending radius. In the present embodiment, all the pipes are parts of the same type, the material grade is LF2M, the pipe specification is D16x1, and the bending radius is R32.

[0050] In the embodiment, it is to be noted that the same type of conduit parts are conduit parts with the same parameters of conduit material grade, conduit specification and shape, etc.

[0051] S2. Preliminary determination of the conduit parts that can be combined bending and determination of the corresponding numerical control bending equipment: the same part combined bending meets the requirements of the three same principles, i.e. the same conduit material grade, the same conduit specification and the same bending radius, based on the three same principles, the conduit parts that meet the combined bending conditions are preliminarily screened out according to the part basic information extracted in step S1; at the same time, according to the conduit specification (D16x1) of the screened conduit parts that can be combined bending, the corresponding numerical control bending forming equipment is selected, so that the conduit development length limit L 设备max is determined to be 3200mm, and the conduit clamping process allowance L 夹持 is determined to be 300mm.

[0052] S3. Extracting the space coordinates of the conduit parts preliminarily selected in step S2, and then converting them into numerical control bending equipment processing parameters, calculating the center line development length L i of each conduit part according to the processing parameters; among the preliminarily selected conduit parts that can be combined bending, the development length L of the combined conduit should not be greater than the conduit development length limit L 设备max , so as to finally determine the conduit parts that can be combined bending, and at the same time obtain the processing parameters of the numerical control bending equipment.

[0053] The center line development length of the conduit part is 109.457mm, and since the conduit part is flared at both ends, the flared process allowance of 4.4mm is required at both ends of the conduit (note: the flared process allowance is obtained through process test and has been solidified). The development length L (conduit blanking length) of the combined conduit of the same part should not be greater than the conduit development length limit L 设备max , and the calculation expression is as follows:

[0054] L = L 夹持 + L1+ L 1工艺 ++ L2+ L 2工艺 +......+ L i + L i工艺 = 300 + N*(109.457 + 4.4*2) ≤ L 设备max = 3200

[0055] As can be seen from the above calculation and analysis, within the equipment forming limit range, up to 24 pieces of the product can be produced by combined bending on one conduit. If 6 pieces of the product are required to be produced according to the production requirements, the development length (conduit blanking length) of the combined conduit is L = 300 + 6*(109.457 + 4.4*2) = 1009.542mm.

[0056] S4. Design of the combined bending data of the pipe parts: the combined bending data of the bendable pipe parts determined in step S3 is designed. The design method is to combine the adjacent pipe connecting positions into straight line segments, and to adjust the rotation angle a at the connecting position, as shown in the following table. The length of the intermediate straight line segment combined from the connecting positions is required to meet the requirement of the minimum length (32 mm) of the intermediate straight line segment of the numerical control machine tool for the bent pipe. According to the bending experience, the trend of the pipe at both ends of the connecting position after the design of the combined bending data is recommended to be in the shape of “Z”, and a can be manually set to 180°. The combined bending data is shown in the following table.

[0057]

[0058]

[0059] S5. Simulation of the bending forming of the combined data of the pipe parts: the combined bending data designed in step S4 is subjected to interference simulation analysis of the bending forming process by the bending forming simulation software. If the pipe parts are subjected to bending forming by using the combined bending data, the pipe forming process does not interfere with the numerical control pipe bending machine, it will be considered that the combined bending data is qualified data, and the qualified combined bending data of the pipe is output, and the combined pipe profile is shown in FIG. 6. If the pipe parts are subjected to bending forming by using the combined bending data of step S4, the pipe bending forming process interferes with the numerical control pipe bending machine, then it returns to step S4 to redesign the combined bending data and then perform simulation analysis, until the parts are formed based on the combined bending data without interference with the machine, and finally the qualified combined bending data of the pipe is output. Figure 3

[0060] S6. Numerical control bending forming: the combined bending data output in step S5 is subjected to numerical control bending forming, and the numerical control forming operation is processed according to the existing mature numerical control bending forming operation steps. The two-dimensional diagram of the pipe after combined bending is shown in FIG. 7. Figure 4

[0061] S7. Measurement and cutting line marking: the pipe parts after combined bending forming are measured by using a vector measuring machine, and the end cutting line is marked on the pipe parts.

[0062] S8. Cutting and end finishing: the multiple sleeve pipe bending parts are roughly cut and divided into several single pipe parts according to the reserved marking position, and then the end of the single pipe part after rough cutting is finished and chamfered. The divided parts are shown in FIG. 8. Figure 5

[0063] S9. Product detection: the product after cutting in step S8 is tested by using a vector measuring machine, and is compared with the theoretical model of the product. If the manufacturing error of the pipe meets the design requirement, the product is determined to be qualified, and can be delivered. If it is not qualified, it is scrapped.​​​

[0064] Embodiment 2

[0065] Referring to the drawings accompanying the specification Figures 6-8 , the embodiment provides a bending forming processing method for different types of catheter parts, and a process flow includes the following steps:

[0066] S1. Extracting basic information of a catheter part to be bent (as shown in the drawings accompanying the specification Figure 6 ): based on a CATIA three-dimensional surface system platform, extracting basic information of a catheter part to be bent, including a catheter material grade, a catheter specification, and a bending radius, as shown in the following table.

[0067]

[0068]

[0069] In the embodiment, it is necessary to note that different types of catheter parts are catheter parts with any one parameter of a catheter material grade, a catheter specification, or an outer shape being different.

[0070] S2. Preliminarily determining catheter parts that can be combined and bent and determining corresponding numerical control bending equipment: the catheter parts that can be combined and bent must meet the three-same principle requirements, i.e., the catheter material grade is the same, the catheter specification is the same, and the bending radius is the same, according to the part basic information extracted in step S1, the catheter parts that meet the combined bending conditions are preliminarily screened out based on the three-same principle, therefore, the part B does not meet the requirements, the catheter parts that can be combined and bent in the embodiment are the three parts A, C, and D; according to the specifications of the catheter parts that can be combined and bent, corresponding numerical control bending forming equipment is selected, so as to determine a catheter unfolding length limit L 设备max is 3200mm, and a catheter clamping process allowance L 夹持 is 400mm.

[0071] S3. Extracting the spatial coordinates of the catheter parts A, C, and D preliminarily selected in step S2, and then converting them into machining parameters of a numerical control machine tool, as shown in the following table.

[0072]

[0073] Since the parts A and D are both two-end flared, the two ends of the catheter need to reserve a flared process allowance of 5.2mm (Note: the flared process allowance is obtained through a process test and has been solidified); the part C is a welded catheter subpart, and the two ends of the catheter need to reserve a welding and fitting allowance of 30mm (obtained through experience). Therefore, the unfolding length L (catheter blanking length) of the catheter after the parts A, C, and D are combined is:

[0074] 400 + 564.67 + 10.4 + 123.682 + 60 + 452.808 + 10.4 = 1621.96

[0075] Therefore, the combined length of the three conduit parts A, C and D is 1621.96 mm, which is less than the limit of the conduit expansion length 3200 mm, i.e. A, C and D meet the combined bending condition. The spatial coordinate transformation processing parameters of the three conduit parts A, C and D and the final processing parameters of the numerical control machine tool.

[0076] S4. Combined bending data design of conduit parts: the conduit parts determined to be combinable in step S3 are designed for bending data combination. The design method is to combine the adjacent conduit connection positions into a straight line segment, while adjusting the rotation angle a at the connection, as shown in the following table. The requirement is to combine the connection positions into a middle straight line segment whose length meets the requirement of the numerical control machine tool for the minimum middle straight line segment length of the bent pipe (76 mm). According to bending experience, the recommended trend of the two ends of the conduit at the connection after the design of the bending data is "Z" type, and a can be manually set to 180°. The bending data of the three parts after combination is shown in the following table.

[0077]

[0078] S5. Simulation of combined data bending of conduit parts: the combined bending data designed in step S4 is analyzed for interference simulation in the bending forming process by a bending forming simulation software. If the conduit parts are bent and formed using the combined data of step S4, the conduit forming process does not interfere with the numerical control bending machine, then the designed qualified conduit part combined bending data is output, and the combined shape of the conduit is shown in FIG. 6; if the conduit parts are bent and formed using the combined bending data of step S4, the conduit bending forming process interferes with the numerical control bending machine, then the combined bending data is redesigned in step S4 and the simulation analysis is performed again until the parts are formed based on the combined bending data without interference with the machine, and finally the designed qualified conduit combined bending data is output. Figure 7

[0079] S6. Numerical control bending forming: the conduit parts are bent and formed according to the combined data output in step S5, and the numerical control forming operation is processed according to the existing mature numerical control bending forming operation steps. The two-dimensional diagram of the conduit parts after combined bending is shown in FIG. 7. Figure 8

[0080] S7. Measurement and cutting line marking: the conduit parts after combined bending and forming are measured by a vector measuring machine, and the end cutting line is marked on the conduit parts.

[0081] S8. Cutting and end finishing: the multiple sleeve conduit parts are roughly cut and divided into several single conduit parts according to the marked line positions, and then the ends of the single conduit parts after rough cutting are finished and chamfered.​​

[0082] S9. Product detection: the product after cutting in step S8 is tested by a vector measuring machine, and compared with a theoretical numerical model of the product. If the catheter manufacturing error meets the design requirements, the product is determined to be qualified, and can be delivered. If it is unqualified, it is scrapped.

[0083] In the description of the present application, it should be understood that the terms "center", "longitudinal", "transverse", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer" and the like indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a hindrance to the scope of protection of the present application.

[0084] In the description of the present application, it should be understood that the terms "set", "mounted", "connected" should be understood broadly, for example, it can be fixedly connected, or detachably connected, or integrally connected; it can be mechanically connected, or electrically connected; it can be directly connected, or indirectly connected through an intermediate medium, or it can be the communication between two elements. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0085] The above is only the preferred embodiment of the present application, and does not make any form of hindrance to the present application. Any simple modification or equivalent change made according to the technical essence of the present application to the above embodiment falls within the scope of protection of the present application.

Claims

1. A method of bending and forming a tube assembly, comprising: The method comprises the following steps: S1. Extracting basic information of the pipe parts to be bent; S2. Preliminarily determining the pipe parts that can be combined and bent and determining the numerical control bending equipment according to the three same principles; S3. Finally determining the pipe parts that can be combined and bent according to the preliminarily selected pipe parts and the numerical control bending equipment, and obtaining the numerical control bending machining parameters based on the finally determined pipe parts; S4. Designing the combined bending data of the pipe parts based on the numerical control bending machining parameters; S5. Combined bending data forming simulation of the pipe parts; S6. Numerical control bending forming of the pipe parts based on the combined bending data. The step S2 comprises: based on the basic information extracted in step S1, preliminarily screening the duct parts that can be combined and bent according to the three same principle, determining the numerical control bending forming equipment according to the specifications of the preliminarily screened duct parts, and finally determining the duct unfolding length limit according to the selected numerical control bending forming equipment and the duct clamping process allowance ; Step S3 includes: extracting the spatial coordinates of the initially selected conduit components from step S2, then converting them into CNC bending equipment processing parameters, and calculating the centerline unfolded length of each conduit component based on the equipment processing parameters. Among the initially selected conduit components that can be combined and bent, the final length of the combined conduit is determined according to... L It should not exceed the limit of the catheter's unfolding length. Based on the principle of combining and bending conduit parts, the processing parameters of the CNC bending equipment were finally determined. ； wherein, is the process allowance required for the part demand The step S5 comprises: performing interference simulation analysis on the combined bending data of the pipe obtained in the step S4 by using a bending forming simulation software; if the combined pipe forming process interferes with the numerical control pipe bending machine, returning to the step S4 to redesign the combined bending data and then performing simulation analysis again until the pipe parts do not interfere with the machine when being formed based on the combined bending data, and finally outputting the qualified combined bending data of the pipe parts.

2. A method of combined bending and forming of a tube set according to claim 1, characterized in that The step S1 comprises: extracting the pipe material brand, the pipe specification and the bending radius according to the numerical model of the pipe parts to be bent.

3. A method of bending and forming a tube assembly according to claim 1, wherein, The step S4 comprises: combining the adjacent pipe connection positions into a straight line segment while adjusting the bending rotation angle α at the connection, and the length of the straight line segment combined by the adjacent pipe connection positions meets the requirement of the equipment on the minimum intermediate straight line segment length of the bent pipe.

4. The method of bending and forming a tube assembly of claim 1 wherein, The step S6 comprises: performing numerical control bending forming of the pipe parts based on the combined bending data output in the step S5.

5. The method of bending and forming a tube assembly of claim 1 wherein, The system further comprises a step S7, which is specifically as follows: measuring the pipe parts after the combined bending forming and drawing corresponding cutting lines.

6. A method of bending and forming a tube assembly according to claim 5, wherein, The system further comprises a step S8, which is specifically as follows: cutting the pipe parts based on the drawn cutting lines, and the pipe parts are divided into a plurality of single pipe parts.

7. A method of bending and forming a tube assembly according to claim 6, wherein, The system further comprises a step S9, which is specifically as follows: testing the product after the cutting in the step S8 by using a vector measuring machine, and comparing the product with a theoretical numerical model of the product; if the manufacturing error of the pipe parts meets the design requirement, the product is determined to be qualified, otherwise, the product is determined to be unqualified.

8. A combination tube bending and forming system characterized by, The system is used to implement the pipe combined bending forming method in any one of claims 1-7, and the system comprises a pipe part data extraction and conversion module, a pipe part combined bending scheme preliminary selection module, a combined bending forming simulation and combined bending scheme optimization module and a combined bending forming module; wherein, The pipe part data extraction and conversion module is used to extract basic information of the pipe parts to be bent, determine the pipe parts that can be combined and bent and the numerical control bending equipment according to the basic information, and finally convert the selected pipe parts that can be combined and bent to obtain the numerical control bending equipment machining parameters; The pipe part combined bending scheme preliminary selection module is used to design the combined bending data of the pipe parts according to the numerical control bending machining parameters; The combined bending forming simulation and combined bending scheme optimization module is used to perform interference simulation analysis on the forming process based on the obtained combined bending data, and optimize and adjust the combined bending data according to the simulation analysis result; The combined bending forming module is used to perform combined bending numerical control forming of the pipe parts according to the optimized and adjusted combined bending data.

Images