Part weight control method based on standardized modeling requirements

Abstract

The invention provides a part weight control method based on standardized modeling requirements. The part weight control method comprises the steps that a solid model of a part is established; determining V and S parameters of the part according to the attributes of the solid model, and selecting proper rho, k and q according to the material type, the raw material specification and the surface treatment mode of the part; the theoretical weight W1 of the part before surface treatment is calculated according to the parameters V, rho and k, and the theoretical weight W2 of the part after surface treatment is calculated according to the parameters V, S, rho, k and q in combination with the surface treatment mode of the part; and carrying out weight inspection after part surface treatment. According to the method, the influence of material tolerance and surface treatment on the part design weight is solved by refining requirements on part modeling and standardizing a part design weight calculation mode, and meanwhile, the weight control accuracy is improved by weight inspection requirements at different stages of production and machining and weight inspection after part surface treatment is strengthened.

Description

Technical Field

[0001] The invention relates to the technical field of aircraft weight control and management, and in particular to a part weight control method based on standardized modeling requirements. Background Art

[0002] Weight control is an important part of aircraft weight design and runs through the entire aircraft design process. Parts weight control is the cornerstone of aircraft weight control. Weight control requires improving the accuracy of theoretical weight calculations on the one hand, and controlling production weight deviations on the other.

[0003] Through the analysis of the weight tolerance of aircraft parts, it is found that one type of weight tolerance is caused by the tolerance of the raw materials of the parts. This tolerance is more prominent in profiles and plate parts that are not processed in the thickness direction. Therefore, a material tolerance correction method is urgently needed to correct the theoretical weight of the parts, reduce the weight tolerance problem in the parts production process, and improve the weight control efficiency.

[0004] On the other hand, each aircraft factory has strict weight control before the surface treatment of aircraft parts, but basically does not involve weight control after the surface treatment of parts. How to calculate and inspect the weight of the aircraft after surface treatment through effective technical means to improve the accuracy of aircraft part weight statistics and reduce aircraft weight errors has become a key issue in aircraft model design. Summary of the invention

[0005] In view of the background technology, the purpose of the present invention is to provide a part weight control method based on standardized modeling requirements. By refining the requirements for part modeling, the calculation method of part design weight is standardized to solve the influence of material tolerance and surface treatment on part design weight. At the same time, through the weight inspection requirements at different stages of production and processing, the weight inspection of parts after surface treatment is strengthened to improve the accuracy of weight control.

[0006] To achieve the above objectives, the technical solution adopted by the present invention is:

[0007] A method for controlling part weight based on standardized modeling requirements comprises the following steps:

[0008] S1. Establish the solid model of the parts;

[0009] S2. Determine the V and S parameters of the part according to the properties of the solid model, and select appropriate ρ, k, q according to the part material type, raw material specifications and surface treatment method;

[0010] S3. Calculate the theoretical weight W1 of the part before surface treatment according to the parameters V, ρ, and k. Calculate the theoretical weight W2 of the part after surface treatment according to the parameters V, S, ρ, k, and q, combined with the surface treatment method of the part:

[0011] S4. Weight inspection of parts before surface treatment;

[0012] S5. Weight inspection of parts after surface treatment.

[0013] Among them, V is the volume parameter of the part, S is the surface area parameter of the part, ρ is the material density parameter of the part, k is the material tolerance correction coefficient of the part, and q is the surface treatment correction coefficient of the part.

[0014] The function of W1 is to correct the influence of material tolerance, and the function of W2 is to further correct the surface treatment weight based on the tolerance correction.

[0015] S1 includes: establishing a 1:1 solid model for each part, and one part corresponds to only one solid model. The part solid model is created by software such as CATIA and Solidworks. Only one 1:1 solid model is allowed under one part model in order to truly reflect the volume and surface area of ​​the part.

[0016] The S4 includes: weighing the parts before the surface treatment process to obtain the weighing weight W1', comparing the difference between W1 and W1' to see whether it meets the weight tolerance requirement, and if so, entering the surface treatment process; otherwise, reworking the parts, and then reprocessing the parts and re-inspecting the weight until the weight inspection requirements are met, or the weight tolerance processing process is entered after approval by the design evaluation.

[0017] Furthermore, S4 includes: calculating the difference △W1 between W1 and W1'; judging whether △W1 meets the specified part weight tolerance, if so, proceeding to the next production process, otherwise, reworking the part, or treating the part for weight deviation.

[0018] Furthermore, the rework of parts mainly includes the following methods: repair / grinding, scrapping and remaking. If the rework still does not meet the weight inspection requirements, the weight deviation can be handled with the approval of the design evaluation.

[0019] The S5 includes:

[0020] After the surface treatment process of the parts, the parts are weighed to obtain the weighing weight W2';

[0021] Calculate the difference △W2 between W2 and W2';

[0022] Determine whether △W2 meets the specified part weight tolerance. If it does, proceed to the next production process. Otherwise, the part will be treated as exceeding the weight tolerance.

[0023] Preferably, the weight tolerance processing of parts includes:

[0024] Receive a weight tolerance processing sheet, which includes basic information of the parts that exceed the tolerance, including: parts processing unit, workshop, part drawing number, name, quantity, batch number, material, theoretical weight, weighed weight, weight tolerance and excess value;

[0025] Receive and store a description of the weighing status of parts with out-of-tolerance weights, an analysis of the causes of the out-of-tolerance weights, and an assessment of the status of the parts with out-of-tolerance weights.

[0026] Compared with the prior art, the present invention has the following advantages:

[0027] 1. Simple implementation;

[0028] 2. Introduce material tolerance correction to solve the weight tolerance problem caused by material deviation;

[0029] 3. Introduce surface treatment correction to improve the accuracy of part weight calculation;

[0030] 4. Carry out weight control at different processing stages to improve the reliability of weight control;

[0031] 5. It is convenient to count the weight after surface treatment, and the aircraft weight statistics are more accurate. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 It is a flow chart of the method for controlling part weight based on the standardized modeling requirements of the present invention;

[0033] Figure 2 This is an example of CATIA part modeling based on standardized modeling requirements. DETAILED DESCRIPTION

[0034] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0035] This embodiment provides a method for controlling part weight based on standardized modeling requirements, and its implementation process is shown in the accompanying drawings, and is specifically as follows:

[0036] Step 1: Create a part solid model according to the following part modeling requirements:

[0037] Establish a 1:1 solid model. Only one solid model is allowed under one part model.

[0038] Establish part volume parameter V and surface area parameter S according to the established solid model;

[0039] Establish the material density parameter ρ of the part according to the part material;

[0040] Establish the material tolerance correction factor k of the part according to the raw material specifications of the part;

[0041] Establish the part surface treatment correction factor q according to the part surface treatment method.

[0042] Step 2: Determine the V and S parameters of the part according to the model attributes, and select appropriate ρ, k, and q according to the part material type, raw material specifications, and surface treatment method;

[0043] Step 3: Calculate the theoretical weight W1 of the part according to the parameters V, ρ, and k: W1 = ρ*V*k; Calculate the theoretical weight W2 of the part according to the parameters V, S, ρ, k, and q: W2 = ρ*V*k+q*S;

[0044] Step 4: Weight inspection before surface treatment: Weigh the parts before the surface treatment process to obtain the weighing weight W1', compare W1 and W1' to see if they meet the weight tolerance requirements, if they do, proceed to the surface treatment process; otherwise, rework the parts, reprocess them, and re-inspect the weight until they meet the weight inspection requirements, or enter the weight tolerance processing process with the approval of the design evaluation;

[0045] Step 5: Weight inspection after surface treatment. After the surface treatment of the parts is completed, weigh them to get the weighed weight W2'. Compare the difference between W2 and W2' to see if it meets the weight tolerance requirement. If it does, this activity ends. Otherwise, enter the weight tolerance processing flow. The tolerance processing flow is the same as that in step 4.

[0046] The weight tolerance processing flow includes: receiving the weight tolerance processing form drafted by the production inspection department, which contains the basic information of the out-of-tolerance parts, including: part processing unit, workshop, part drawing number, name, quantity, batch number, material, theoretical weight, weighing weight, weight tolerance, and out-of-tolerance (value); receiving the description and confirmation of the weighing status of the out-of-tolerance parts by the production inspection department, the analysis and confirmation of the cause of the out-of-tolerance by the process department, the evaluation and confirmation of the status of the out-of-tolerance parts by the drawing designer, and the confirmation by the aircraft weight control professional department.

[0047] Based on the above implementation method, taking CATIA modeling as an example, it is elaborated in detail:

[0048] First, create a 1:1 solid part model using CATIA software;

[0049] Secondly, create the parameter part material density ρ in the CATIA model. ρ is related to the material type of the material part. Taking aluminum alloy as an example, ρ is 2768kg / m 3 ,See Figure 2 As shown;

[0050] Secondly, create a parameter tolerance correction coefficient k in the CATIA model. k is related to the dimensional tolerance band distribution of the raw material. For positive tolerance materials, the tolerance correction coefficient should be greater than 1, and for negative tolerance materials, the tolerance correction coefficient should be less than 1. Taking the negative tolerance of -5% as an example, k is 0.98.

[0051] Secondly, the parameter surface treatment correction coefficient q is created in the CATIA model. q is related to the surface treatment method of the part. The main influencing factors include the surface treatment method of the part, the paint material, the thickness, etc. Taking the spraying of 2 layers of primer (thickness 20-45μm) as an example, the value of q is 0.068kg / m 2 ;

[0052] Secondly, create the parameter volume V and surface area S in the CATIA model. V and S are determined by the part dimensions. They can be directly measured by the 1:1 solid part model created by CATIA. In this example, V is measured to be 2.534×10 -4 m3, S was measured to be 0.294m 2 ;

[0053] Secondly, create a parameter part weight W1 in the CATIA model. W1 is calculated by ρ*V*k. The calculated W1 in the example is 0.687kg.

[0054] Secondly, create a parametric part weight W2 in the CATIA model. W2 is calculated by ρ*V*k+q*S. The example calculation of W2 is 0.707kg.

[0055] Secondly, before the surface treatment process of the parts, the weight of the parts before surface treatment is checked. The weight W1' before the surface treatment is determined by weighing and measuring the parts. The weight |W1'-W1| is compared and analyzed to see whether it meets the prescribed weight tolerance requirements. If it meets the requirements, it will enter the next process. Otherwise, the parts will be reworked. After the parts are reprocessed, the weight will be checked again until the weight tolerance requirements are met, or the weight tolerance processing process is entered after the design evaluation is approved.

[0056] Secondly, after the surface treatment process of the parts is completed, the parts are subjected to another weight inspection. The weight W2' of the parts after surface treatment is determined by weighing and measuring the parts. The weight |W2'-W2| is compared and analyzed to see whether it meets the prescribed weight tolerance requirements. If it does, the parts are qualified for weight inspection and delivered for acceptance; otherwise, it enters the weight tolerance processing process.

[0057] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the field can easily think of various equivalent modifications or substitutions within the technical scope disclosed by the present invention, and these modifications or substitutions should all be covered within the protection scope of the present invention.

Claims

1. A method for controlling part weight based on standardized modeling requirements, characterized in that: The following steps are involved: S1. Establish the solid model of the parts; S2. Determine the V and S parameters of the part according to the properties of the solid model, and select appropriate ρ, k, q according to the part material type, raw material specifications and surface treatment method; S3. Calculate the theoretical weight W1 of the part before surface treatment according to the parameters V, ρ, and k. Calculate the theoretical weight W2 of the part after surface treatment according to the parameters V, S, ρ, k, and q, combined with the surface treatment method of the part: S4. Weight inspection of parts before surface treatment; S5. Weight inspection of parts after surface treatment. Among them, V is the volume parameter of the part, S is the surface area parameter of the part, ρ is the material density parameter of the part, k is the material tolerance correction coefficient of the part, and q is the surface treatment correction coefficient of the part.

2. The part weight control method according to claim 1, characterized in that: The S1 includes: establishing a 1:1 solid model for each part, and one part corresponds to only one solid model.

3. The part weight control method according to claim 1, characterized in that: The calculation method of W1 is: W1=ρ*V*k; the calculation method of W2 is: W2=ρ*V*k+q*S.

4. The part weight control method according to claim 1, characterized in that: The S4 includes: obtaining the weighing weight W1' of the part before the part surface treatment process, calculating the difference △W1 between W1 and W1', and judging whether △W1 meets the specified part weight tolerance requirement. If so, entering the surface treatment process, otherwise, reworking the part, and then entering S4 for weight inspection before surface treatment, or entering the weight tolerance processing process at the same time.

5. The part weight control method according to claim 4, characterized in that: Reworking of parts may include the following: repair, grinding and / or scrapping.

6. The part weight control method according to claim 1, characterized in that: The S5 includes: After the surface treatment process of the part, the weighing weight W2' of the part is obtained; Calculate the difference △W2 between W2 and W2'; Determine whether △W2 meets the specified part weight tolerance. If so, proceed to the next production process; otherwise, enter the weight tolerance processing process.

7. The parts weight control method according to claim 4 or 6, characterized in that: The weight tolerance processing of parts includes: Receive a weight tolerance processing sheet, which includes basic information of the parts that exceed the tolerance, including: parts processing unit, workshop, part drawing number, name, quantity, batch number, material, theoretical weight, weighed weight, weight tolerance and excess value; Receive and store a description of the weighing status of parts with out-of-tolerance weights, an analysis of the causes of the out-of-tolerance weights, and an assessment of the status of the parts with out-of-tolerance weights.

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