Rapid evaluation method for stamping product quality

Abstract

The invention provides a rapid evaluation method for stamping product quality. The rapid evaluation method comprises the steps that stamping quality defects of a product are identified, defective parts, corresponding to the stamping quality defects of the product, of the product are obtained, local sample pieces corresponding to the defective parts of the product are manufactured, and AUDIT quality evaluation of all the local sample pieces is qualified; carrying out defect marking on the local sample; taking the defect part of the product as a review part; and respectively comparing the stamping quality defect of each review part of the product with the stamping quality defect of each corresponding local sample, and evaluating the stamping quality qualification condition of each review part. The method has the advantages that the quality defect change of the review part of the product can be comprehensively and timely reflected, the comparison is more accurate and flexible, and meanwhile, the product quality monitoring labor division is refined; the method has efficient timeliness, can quickly identify defects, carries out sample piece risk prompt, and greatly saves the quality judgment time caused by product quality fluctuation.

Description

Technical Field

[0001] The invention relates to the technical field of automobile stamping, and in particular to a method for quickly evaluating the quality of stamping products. Background Art

[0002] The quality production standard sample is a quality standard commonly used in the production process of automobile stamping parts. It is to ensure the stability of the quality and facilitate comparison and reference when the product changes or quality analysis is required (valid for one year). On the one hand, due to site limitations, the production site cannot store multiple quality production standard parts. On the other hand, according to quality review requirements, only one quality production standard sample can be set. The current quality production standard sample is a complete stamping part.

[0003] However, in the stamping production process, uncontrollable factors such as press accuracy, sheet material performance, oil film thickness, mold temperature, stroke rhythm, irreversible damage, etc. will cause quality fluctuations such as cracking, necking, dark pits, thinning rate, and forming of stamped parts. Due to the diversity of automotive parts structure, the quality defect changes caused by these uncontrollable factors cannot be fully and timely reflected in the traditional quality production standard samples. At the same time, the time of their generation and elimination is not controlled. This complex quality change process brings serious troubles to the quality control standards of the production system, resulting in a large amount of production time loss and quality defective products. Due to the inevitability of quality fluctuations of stamping parts, the current method of guiding production and controlling product quality with quality standard samples cannot play a comprehensive and effective guiding role.

[0004] Invention patent content

[0005] In order to solve the above technical problems, the present invention provides a method for quickly evaluating the quality of stamping products, which divides the defective parts of the products as local samples to evaluate the stamping quality of the products and timely monitor the fluctuation of product quality.

[0006] The present invention solves the technical problem by adopting the following technical solution:

[0007] A rapid evaluation method for stamping product quality comprises the following steps:

[0008] Step 1: Identify the stamping quality defects of the product, obtain the defective parts of the product corresponding to the stamping quality defects of the product, make local samples corresponding to the defective parts of the product, and each local sample passes the AUDIT quality review;

[0009] Step 2: Mark defects on local samples;

[0010] Step 3: Use the defective parts of the product as the review parts;

[0011] Step 4: Compare the stamping quality defects of each evaluation part of the product with the stamping quality defects of each corresponding local sample, and evaluate the stamping quality compliance of each evaluation part.

[0012] Furthermore, the method for making a partial sample comprises the following steps:

[0013] Step 11. Among the multiple samples that have passed the AUDIT quality review, find the sample with the largest stamping quality defect in each review part as the reference sample;

[0014] Step 12: Segment the review area of ​​the reference sample as a partial sample.

[0015] Furthermore, the method for making a partial sample also includes the following steps:

[0016] Step 111, stamping and producing one or n batches of samples, performing AUDIT quality review on each batch of samples, and finding out the batches of samples that pass the AUDIT quality review, where n=1, 2, 3, ...;

[0017] Step 112, among the samples of each batch that have passed the AUDIT quality review, find the sample with the largest stamping quality defect in each review position of each batch as the reference sample of each batch;

[0018] Step 113, segmenting the review parts of the reference samples of each batch as batch samples of each batch;

[0019] Step 114: Take the batch of samples with the largest stamping quality defects among the batches of samples as local samples.

[0020] Furthermore, when a batch of samples is produced by stamping and the AUDIT quality review of the batch of samples is qualified, the batch of samples of the batch will be used as partial samples;

[0021] When stamping produces n batches of samples, the AUDIT quality review of the samples from batches 1 to n-1 fails, and the AUDIT quality review of the samples from batch n passes, the batch samples that pass the AUDIT quality review are the nth batch samples, and the batch samples of the nth batch are used as partial samples;

[0022] When n batches of samples are produced by stamping and the AUDIT quality review of the 1st to nth batches of samples are all qualified, find out the batch samples of each batch, and compare the batch samples of each batch to find out the batch sample of the i-th batch with the largest stamping quality defects as the local sample, where i = 1, 2, 3...

[0023] Furthermore, the stamping quality defects of each review part of the product are compared with the stamping quality defects of each corresponding local sample. When the stamping quality defects of the review part of the product exceed those of the local sample, and the review part of the product passes the AUDIT quality review, the review part of the product is segmented as a local sample. The local sample can be quickly replaced, which can guide product quality control in the production process more efficiently and accurately.

[0024] Furthermore, when a defective part has k defect types, k local samples are made for the defective part, where k = 1, 2, 3..., so that the stamping quality defects of the same defective part of the product can be compared, and the product quality of the entire production process can be monitored and evaluated.

[0025] Furthermore, the partial samples of the body in white include one or more of the upper crossbeam end sample, the upper crossbeam middle sample, the triangular window sample, the sample below the A-pillar, the sample below the B-pillar and the fuel tank port sample.

[0026] Furthermore, the stamping quality defects of the product include dark pits at the ends, slip lines on the upper cross beam, slip lines on the tail, dark pits in the triangular windows, necking at the arc below the A-pillar, cracks at the arcs on both sides of the B-pillar, necking at the arcs on both sides of the B-pillar, and dark pits around the fuel tank opening.

[0027] Furthermore, the partial samples of the body in white also include one or more of fender samples, hood outer panel samples, side panel samples, roof samples, rear cover outer panel samples, rear cover inner panel samples, door outer panel samples and door inner panel samples.

[0028] Compared with the prior art, the present invention has the following beneficial effects:

[0029] (1) The use of partial samples can comprehensively and timely reflect the changes in quality defects of the product's review parts, making the comparison more accurate and flexible, and convenient to achieve process quality control, while refining the division of labor for product quality monitoring; it has high efficiency and timeliness, can quickly identify defects, and provide sample risk warnings, greatly saving the quality judgment time caused by product quality fluctuations, and effectively controlling the generation of scrapped products and the outflow of defective products.

[0030] (2) Local samples in areas with local quality fluctuations can be quickly replaced to more efficiently and accurately guide product quality control during the production process.

[0031] (3) The local sample is small in size, has great flexibility in actual operation, is easy to operate, and can be easily completed by one person, saving personnel costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1A schematic diagram of a partial sample of the method for quickly evaluating the quality of stamping products of the present invention.

[0033] Figure 2 It is a schematic diagram of the fluctuation of stamping quality defects at an evaluation position of the present invention.

[0034] In the figure: 100-body in white; 1-upper crossbeam end sample; 2-upper crossbeam middle sample; 3-triangular window sample; 4-below A-pillar sample; 5-below B-pillar sample; 6-fuel tank port sample. DETAILED DESCRIPTION

[0035] In order to make the objectives, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below with reference to the accompanying drawings and embodiments.

[0036] The present invention provides a method for quickly evaluating the quality of stamping products, comprising the following steps:

[0037] Step 1: Identify the stamping quality defects of the product, obtain the defective parts of the product corresponding to the stamping quality defects of the product, make local samples corresponding to the defective parts of the product, and each local sample passes the AUDIT quality review;

[0038] Step 2: Mark defects on local samples;

[0039] Step 3: Use the defective parts of the product as the review parts;

[0040] Step 4: Compare the stamping quality defects of each evaluation part of the product with the stamping quality defects of each corresponding local sample, and evaluate the stamping quality compliance of each evaluation part.

[0041] By testing and analyzing the stamping quality of stamped parts, it is possible to identify the stamping quality defects of the product and obtain the defective parts of the product corresponding to the stamping quality defects; based on production experience, it is also possible to obtain the parts that are prone to defects in the stamping production process, find the defective parts of the product, and the defective parts can be used as the review parts for testing the qualified stamping quality of the product. Preferably, the defective parts of the product have distinct edges or surfaces, so that the local samples corresponding to the defective parts have a high degree of recognition, which is convenient for comparison with the review parts of the product. The defective parts need to pass the AUDIT quality review (the AUDIT quality review reaches C1 level and below as the qualified level), that is, the defective parts are within the control range of the quality standard, and the product can be subject to an AUDIT quality review as a whole. If the product passes the AUDIT quality review, then the defective parts of the product pass the AUDIT quality review, or the defective parts can be directly subject to an AUDIT quality review.

[0042] Defect identification and marking of partial samples can mark the defect type and location, and each review part of the product can be compared with the stamping quality defects of the corresponding partial samples to evaluate the stamping quality of each review part, so as to monitor the quality fluctuation of the stamping production process. In order to make the comparison of the stamping quality defects of the review part and the partial sample clearer and more accurate, the oilstone grinding method, hand touch method, gauze grinding method, etc. can be used to identify product defects. 3D scanning method can also be used. After 3D scanning of the partial sample and the product, the scanning results can be compared to quickly evaluate the review part of the product to improve efficiency and the level of automated detection.

[0043] If the stamping quality defect of the review part is not greater than the stamping quality defect of the corresponding local sample, it indicates that the stamping quality of the review part is qualified relative to the local sample, the stamping quality is stable, and there is no large fluctuation. The production process can be maintained to continue production. If the stamping quality of each review part of the product is qualified, the stamping quality of the product is qualified. If the stamping quality defect of the review part is larger than the stamping quality defect of the corresponding local sample, it indicates that the stamping quality of the review part is unqualified relative to the local sample, and the product quality fluctuates greatly. It is necessary to further conduct an AUDIT quality review on the product, and guide the production process according to the AUDIT quality review. When the AUDIT quality review is qualified, the production process can be maintained to continue production. When the AUDIT quality review is unqualified, the production process needs to be adjusted, for example, the press parameters, mold forming gap, etc., so that the quality of the product is restored to the control range of the quality standard of the local sample, and the product quality returns to a stable state of fluctuation.

[0044] In this way, compared with the quality production standard samples of large parts, by comparing with the local samples, the quality defect changes of the product review parts can be fully and timely reflected, which has high timeliness and can quickly identify defects and provide sample risk warnings based on the quality changes caused by a series of factors such as press accuracy, sheet material performance, oil film index, mold damage, and process changes, which greatly saves the quality judgment time caused by product quality fluctuations, and can adjust the production process in time to avoid downtime. At the same time, it effectively controls the generation of waste returns and the outflow of defective products. For example, when the side sliding line uses quality standard samples for comparison, there will be 7-8 times of product stamping quality defects that are too large in 20,000 stamping products, and the fluctuation situation that quality judgment needs to be carried out, and each quality judgment takes about 40 minutes; while when using local samples for comparison, there will be 2-3 times of product stamping quality defects that are too large in 120,000 stamping products, and the fluctuation situation that quality judgment needs to be carried out. Using local samples for comparison greatly reduces the frequency of product stamping quality fluctuations, and reduces the time and workload of quality judgment. Moreover, partial samples are more flexible and easier to operate in actual practice. In the past, the comparison of larger samples required the joint efforts of two or more people, but partial samples are small in size and can be easily completed by one person, saving personnel costs.

[0045] like Figure 1 As shown, the partial samples of the body-in-white 100 include one or more of the upper crossbeam end sample 1, the upper crossbeam middle sample 2, the triangular window sample 3, the A-pillar lower sample 4, the B-pillar lower sample 5 and the fuel tank port sample 6. The body-in-white 100 can be segmented in the form of a nine-square grid to obtain each partial sample. Accordingly, the stamping quality defects of the product include end pits, upper crossbeam slip lines, tail slip lines, triangular window pits, necking at the arc below the A-pillar, cracks at the arcs on both sides of the B-pillar, necking at the arcs on both sides of the B-pillar, and pits around the fuel tank port. By comparing with the partial samples, the stamping quality defects of each review part can be quickly identified. The partial sample can also set the thickness thinning rate standard at the arc, so as to quickly determine the qualified thinning rate of the surface thickness at the arc of the product. The partial sample is small in size, and the measurement of the thinning rate at the arc has high operability and convenience. The partial samples of the body-in-white 100 also include one or more of the fender samples, the hood outer panel samples, the side panel samples, the roof samples, the rear cover outer panel samples, the rear cover inner panel samples, the door outer panel samples and the door inner panel samples. Of course, according to the stamping quality of each part of the body-in-white 100, corresponding samples of defective parts of other parts can also be provided.

[0046] The method for making a partial sample comprises the following steps:

[0047] Step 11. Among the multiple samples that have passed the AUDIT quality review, find the sample with the largest stamping quality defect in each review part as the reference sample;

[0048] Step 12: Segment the review area of ​​the reference sample as a partial sample.

[0049] In step 11, the stamping quality defects of the evaluation parts of the reference sample are taken as the reference, and the stamping quality defects of the evaluation parts corresponding to all other samples are not greater than the stamping quality defects of the evaluation parts of the reference sample, that is, the stamping quality defects of the evaluation parts of each sample are within the quality standard control range based on the stamping quality defects of the evaluation parts of the reference sample, and the quality fluctuation of the evaluation parts of each sample is stable. The reference samples with the largest stamping quality defects at each evaluation part can be the same sample or different samples. For example, the reference samples with the largest stamping quality defects at each evaluation part are all sample 1, or the reference sample with the largest stamping quality defects at one evaluation part is sample 1, and the reference sample with the largest stamping quality defects at another evaluation part is sample 2.

[0050] After obtaining the reference sample, the review part can be directly cut out from the reference sample as a local sample. The stamping quality defects of the local sample are used as the benchmark, and the quality fluctuations of the corresponding review parts of all other samples are stable. The local sample is cut from the stamping product, with distinct edges or surfaces, and has a high degree of recognition, which is convenient for comparison with the review parts of the product. In addition, the partial sample can be taken to the production position for comparison, and can be fitted to the corresponding position of the product, and the review part can be accurately and quickly identified. The defect comparison is more accurate and flexible, and the process quality control is conveniently realized. At the same time, the division of product quality monitoring is refined, and the quality fluctuations of each review part of the product are independently monitored.

[0051] Specifically, the method for making a partial sample also includes the following steps:

[0052] Step 111, stamping and producing one or n batches of samples, performing AUDIT quality review on each batch of samples, and finding out the batches of samples that pass the AUDIT quality review, where n=1, 2, 3, ...;

[0053] Step 112, among the samples of each batch that have passed the AUDIT quality review, find the sample with the largest stamping quality defect in each review position of each batch as the reference sample of each batch;

[0054] Step 113, segmenting the review parts of the reference samples of each batch as batch samples of each batch;

[0055] Step 114: Take the batch of samples with the largest stamping quality defects among the batches of samples as local samples.

[0056] Stamping products are generally produced in batches, and the number of samples produced in each batch can be the same or different. When conducting an AUDIT quality review on batch samples, all samples in the batch can be reviewed, or samples from the batch can be reviewed. Among the batch samples that have passed the AUDIT quality review, the benchmark samples of each batch can be found, and then the review parts of the benchmark samples of each batch can be divided out as batch samples of each batch; then the batch samples of each batch can be compared with each other, and the batch samples with the largest stamping quality defects in each batch sample can be used as local samples.

[0057] For stamping products with shallow forming depth, simple forming and simple forming process design, such as door outer panels and hood outer panels, the quality fluctuations during the production process are generally relatively stable, and partial samples can be obtained through one batch or a few batches of production. For deep drawing forming parts, such as side panels, fenders, door inner panels, etc., the forming depth is large, and more sheet metal needs to flow into the mold during the drawing process to complete the forming. The process is affected by factors such as fluctuations in the performance of different batches of sheet metal, fluctuations in material thickness, and fluctuations in the temperature rise caused by deep drawing. The quality fluctuations during the forming process are large, and all stamping quality defects cannot be fully reflected in a single batch of stamping products. More batches of production are required to obtain partial samples.

[0058] Specifically, when a batch of samples is produced by stamping and the AUDIT quality review of the batch of samples is qualified, the batch of samples of the batch will be used as partial samples;

[0059] When stamping produces n batches of samples, the AUDIT quality review of the samples from batches 1 to n-1 fails, and the AUDIT quality review of the samples from batch n passes, the batch samples that pass the AUDIT quality review are the nth batch samples, and the batch samples of the nth batch are used as partial samples;

[0060] When n batches of samples are produced by stamping and the AUDIT quality review of the 1st to nth batches of samples are all qualified, find out the batch samples of each batch, and compare the batch samples of each batch to find out the batch sample of the i-th batch with the largest stamping quality defects as the local sample, where i = 1, 2, 3...

[0061] For example, when three batches of samples are produced by stamping, the first and second batches fail the AUDIT quality review, and the third batch passes the AUDIT quality review, the batch samples that pass the AUDIT quality review are the third batch samples, and the batch samples of the third batch are used as local samples. When the AUDIT quality review of the first to third batches of samples are all qualified, the batch samples of the three batches are found respectively, and the batch samples of the three batches are compared with each other to find the batch sample with the largest stamping quality defects as the local sample. For example, the first batch produces 100 samples, and the batch sample obtained is Sample 1; the second batch produces 400 samples, and the batch sample obtained is Sample 2; the third batch produces 500 samples, and the batch sample obtained is Sample 3; among the 3 samples, Sample 2 has the most serious defects, so Sample 2 is used as a local sample, and the defects of other samples are compared with Sample 2. The defects are all smaller than those of Sample 2, that is, taking the defects of Sample 2 as the benchmark, the product quality fluctuations are the most stable and are all within the control range of the quality standards.

[0062] Stamping products require a long period of process debugging and mold adjustment before mass production. Partial samples can be prepared during the production process debugging and when producing sample vehicles to monitor the product quality fluctuations in the subsequent debugging production process and mass production process, and guide the production process. The stamping quality defects of each review part of the product are compared with the stamping quality defects of each corresponding local sample. When the stamping quality defects of the review part of the product exceed the stamping quality defects of the local sample, and the product review part AUDIT quality review is qualified, the review part of the product can be divided as a new local sample, replacing the original local sample to monitor the product quality fluctuations in the subsequent production process and guide the production process. In this way, the local samples in the local quality fluctuation area can be quickly replaced, and the product quality control in the production process can be guided more efficiently and accurately. The scope of quality standard control can also be expanded to avoid the need for quality assurance personnel to go to the site for quality judgment, thereby avoiding a large number of quality judgment stoppages, reducing stoppage costs, and avoiding the generation of a large number of returned products and waste products.

[0063] For example, the fluctuation of stamping quality defects in one review area is as follows: Figure 2As shown, horizontal a is the stamping quality defect level that passes the AUDIT quality review, horizontal b is the stamping quality defect level of the first local sample, and horizontal c is the stamping quality defect level of the second local sample. The initial local sample obtained is the first local sample. After the start of production, the stamping quality defects of the review part are compared with the first local sample, and the staff can quickly judge whether the stamping quality of the review part is qualified. As the stamping production process proceeds, from the start of production to the production quantity N1, the stamping quality defects of the review part are no greater than the stamping quality defects of the first local sample (the stamping quality defects of the review part do not exceed curve c). From the start of production to the production quantity N1, the stamping quality of the review part of the product is qualified and is within the quality standard control range of the first local sample. The stamping quality defect of the review part of the product with production quantity N1 is greater than the stamping quality defect of the first partial sample, and the review part of the product with production quantity N1 is qualified in the AUDIT quality review (the stamping quality defect of the review part does not exceed curve a). At this time, the review part of the product with production quantity N1 can be divided to form a second partial sample as a new partial sample. The subsequent production keeps the production process unchanged, and the stamping quality defect of the second partial sample is used as the benchmark to compare the stamping quality defects of the review part of the product with the second partial sample. The stamping quality defect of the review part of the products between production quantity N1 and production quantity N2 is not greater than the stamping quality defect of the second partial sample (the stamping quality defect of the review part does not exceed curve b). The stamping quality of the review part of the products between production quantity N1 and production quantity N2 is qualified and is within the quality standard control range of the second partial sample. The stamping quality defect of the review part of the product with production quantity N2 is greater than the stamping quality defect of the second partial sample, and the AUDIT quality review of the review part of the product with production quantity N2 fails. At this time, it is necessary to adjust the production process so that the stamping quality defect of the review part of the product is not greater than the stamping quality defect of the second partial sample, and restore it to within the control range of the quality standard of the second partial sample.

[0064] Some defective parts have multiple defect types. When a defective part has k defect types, k local samples are made for the defective part, where k = 1, 2, 3.... Multiple local samples are set for a defective part, so that the stamping quality defects of the same defective part of products in different production periods can be compared respectively, or the defects of products with multiple stamping quality defects in a defective part can be compared respectively, so as to monitor and evaluate the product quality of the entire production process and the various stamping quality defects of the product. For example, at the part above the center pillar of the side panel, the B-pillar will have a pit defect because the material cannot be pressed on the outside during the start of production. After the pressurization debugging is qualified, the continuous production mold will expand slightly after being heated, and the feeding resistance of the sheet metal will increase. The ridgeline above the B-pillar will produce a slip line defect, and the pit defect and the slip line defect are located at the same position.

[0065] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A method for rapid evaluation of stamping product quality, characterized in that: The following steps are involved: Step 1: Identify the stamping quality defects of the product, obtain the defective parts of the product corresponding to the stamping quality defects of the product, make local samples corresponding to the defective parts of the product, and each local sample passes the AUDIT quality review; Step 2: Mark defects on local samples; Step 3: Use the defective parts of the product as the review parts; Step 4: Compare the stamping quality defects of each evaluation part of the product with the stamping quality defects of each corresponding local sample, and evaluate the stamping quality compliance of each evaluation part.

2. The rapid evaluation method for stamping product quality according to claim 1, characterized in that: The method for making a partial sample comprises the following steps: Step 11. Among the multiple samples that have passed the AUDIT quality review, find the sample with the largest stamping quality defect in each review part as the reference sample; Step 12: Segment the review area of ​​the reference sample as a partial sample.

3. The rapid evaluation method for stamping product quality according to claim 2, characterized in that: The method for making a partial sample also includes the following steps: Step 111, stamping and producing one or n batches of samples, performing AUDIT quality review on each batch of samples, and finding out the batches of samples that pass the AUDIT quality review, where n=1, 2, 3, ...; Step 112, among the samples of each batch that have passed the AUDIT quality review, find the sample with the largest stamping quality defect in each review position of each batch as the reference sample of each batch; Step 113, segmenting the review parts of the reference samples of each batch as batch samples of each batch; Step 114: Take the batch of samples with the largest stamping quality defects among the batches of samples as local samples.

4. The rapid evaluation method for stamping product quality according to claim 3 is characterized in that: When a batch of samples is produced by stamping and the samples are qualified by AUDIT quality review, the batch samples of this batch will be used as partial samples; When stamping produces n batches of samples, and the samples from batches 1 to n-1 fail the AUDIT quality review, and the samples from batch n pass the AUDIT quality review, the batch samples that pass the AUDIT quality review are the nth batch samples, and the batch samples of the nth batch are used as partial samples; When n batches of samples are produced by stamping and the AUDIT quality review of the 1st to nth batches of samples are all qualified, find out the batch samples of each batch, and compare the batch samples of each batch to find out the batch sample of the i-th batch with the largest stamping quality defects as the local sample, where i = 1, 2, 3...

5. The method for rapid evaluation of stamping product quality according to claim 3, characterized in that: The stamping quality defects of each review part of the product are compared with the stamping quality defects of each corresponding local sample. When the stamping quality defects of the review part of the product exceed the stamping quality defects of the local sample and the review part of the product passes the AUDIT quality review, the review part of the product is segmented as a local sample.

6. The rapid evaluation method for stamping product quality according to claim 1, characterized in that: When a defective part has k defect types, k local samples are made for the defective part, where k = 1, 2, 3, ...

7. The rapid evaluation method for stamping product quality according to claim 1 is characterized in that: The partial samples of the body in white include one or more of the upper crossbeam end sample, the upper crossbeam middle sample, the triangular window sample, the sample below the A-pillar, the sample below the B-pillar and the fuel tank port sample.

8. The method for rapid evaluation of stamping product quality according to claim 7, characterized in that: The stamping quality defects of the product include dark pits at the ends, sliding lines on the upper cross beam, sliding lines on the tail, dark pits in the triangular windows, necking at the arc below the A-pillar, cracks at the arc on both sides of the B-pillar, necking at the arc on both sides of the B-pillar, and dark pits around the fuel tank opening.

9. The rapid evaluation method for stamping product quality according to claim 1, characterized in that: The partial samples of the body in white also include one or more of the fender samples, the hood outer panel samples, the side panel samples, the roof samples, the rear cover outer panel samples, the rear cover inner panel samples, the door outer panel samples and the door inner panel samples.

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