Nondestructive testing method applied to thin-wall product

Abstract

The invention discloses a nondestructive testing method applied to a thin-wall product, and relates to the technical field of product leakage detection, a vacuum box and a product arranged in the vacuum box are included, and the method comprises the steps that S1, the wall thickness of the product is detected, the pressure difference range of the product and the vacuum box is set, and the pressure difference range is guided into a control system; s2, vacuumizing the product and a vacuum box for bearing the product; s3, carrying out helium leak detection operation on the product; s4, vacuum breaking operation is carried out on the product and the vacuum box bearing the product; and S5, the product is taken out after detection is completed. In the detection work process, the pressure difference between the product and the vacuum box can be accurately and effectively recognized, in the evacuation and vacuum breaking process, the air flow speed can be accurately and effectively controlled, it is ensured that the pressure difference between the product and the vacuum box is always within the safety range, and the product quality is improved. The phenomena of sinking and bulging caused by the fact that the pressure difference does not meet the standard in the leakage detection operation process of the product are effectively avoided, and the protection effect on the thin-wall product is achieved.

Description

Technical Field

[0001] The present invention relates to the technical field of product leakage detection, and particularly to a non-destructive detection method applied to thin-walled products. Background Art

[0002] Helium leak detection in a vacuum chamber is a commonly used detection method, mainly used to detect the leakage of vacuum seals. Its core principle is to use helium as a tracer gas, fill helium into the workpiece, and perform detection in a vacuum chamber. Then, a high-precision helium mass spectrometer leak detector is used to quickly and accurately determine the leakage of the workpiece, and the leak rate of the detected product is obtained by analyzing the helium distribution.

[0003] In the existing helium detection method in a vacuum chamber, before and after filling helium into the product and performing the detection operation, it is necessary to evacuate and break the vacuum of the vacuum chamber and the inside of the product to form a helium detection environment and be able to take out the product smoothly. However, during the process of performing helium detection on thin-walled products, when evacuating and breaking the vacuum of the vacuum chamber and the inside of the product, since the evacuation and breaking of the vacuum are separate pipelines and the air flow velocities are different, it is easy to cause a pressure difference between the inner cavities of the vacuum chamber and the product. If the pressure difference exceeds the safe range, it is easy to cause the thin-walled product to have dents and bulges, resulting in damage to the product and inability to be used normally. Therefore, the present application provides a non-destructive detection method applied to thin-walled products to meet the requirements. Summary of the Invention

[0004] In view of the above problems, the present application provides a non-destructive detection method applied to thin-walled products.

[0005] To achieve the above object, the present application provides the following technical solution: A non-destructive detection method applied to thin-walled products, including a vacuum chamber and a product disposed in the vacuum chamber, the non-destructive detection method comprising the following steps:

[0006] S1: Detect the wall thickness of the product, set the pressure difference range between the product and the vacuum chamber, and import the pressure difference range into the control system;

[0007] S2: Perform an evacuation operation on the product and the vacuum chamber carrying the product. When the evacuation speed of the product cavity or the vacuum chamber cavity is too fast, resulting in the pressure difference between the product and the vacuum chamber exceeding the pressure difference range set in step S1, the control system controls the product cavity or the vacuum chamber cavity to pause the evacuation operation until the pressure difference between the product cavity and the vacuum chamber cavity meets the set pressure difference range, and then perform the evacuation operation on the product cavity or the vacuum chamber cavity again until the evacuation operation is completed:

[0008] S3: Perform a helium leak detection operation on the product;

[0009] S4: Perform air-breaking operation on the product and the vacuum chamber containing the product. When the air-breaking of the cavity of the vacuum chamber is completed relatively quickly, perform differential pressure detection on the cavities of the product and the vacuum chamber. If the differential pressure does not meet the range set in step S1, the control system adjusts the air flow rate during the air-breaking of the product cavity until the differential pressure between the product and the vacuum chamber meets the range;

[0010] S5: After the detection is completed, take out the product.

[0011] Further, step S3 includes the following steps:

[0012] S31: Fill the workpiece with high-pressure nitrogen. If there is a leakage phenomenon in the workpiece, helium leaks into the interior of the vacuum chamber. Otherwise, there is no change inside the vacuum chamber body;

[0013] S32: The helium detection system connected to the vacuum chamber detects whether there is leaked helium in the vacuum chamber. If there is a helium leakage phenomenon in the workpiece, the helium detection system transmits a leakage signal to the control system, and the control system alarms and marks the leaking product. Otherwise, if there is no helium leakage phenomenon in the workpiece, the helium detection system transmits the detection result to the control system, and the control system marks the product as qualified:

[0014] S33: Recover the helium in the workpiece.

[0015] Further, after placing the product in the vacuum chamber in step S2, it is necessary to operate the positioning structure inside the vacuum chamber to press the product tightly to maintain the stability of the product during the evacuation and air-breaking processes.

[0016] Further, the vacuum chamber is provided with a chamber evacuation pipeline connected to the inside of the chamber and a workpiece evacuation pipeline connected to the product. A workpiece evacuation regulating valve and a chamber evacuation regulating valve are respectively provided on the workpiece evacuation pipeline and the chamber evacuation pipeline. When the control system controls the evacuation operation of the product and the vacuum chamber containing the product, the workpiece evacuation regulating valve or the chamber evacuation regulating valve can respond.

[0017] Further, the vacuum chamber is provided with a chamber air-breaking pipeline connected to the inside of the chamber and a workpiece air-breaking pipeline connected to the product. The workpiece air-breaking pipeline is connected to the workpiece evacuation pipeline. A workpiece air-breaking valve and a chamber air-breaking valve are respectively provided on the workpiece air-breaking pipeline and the chamber air-breaking pipeline. When the control system performs the air-breaking operation on the product and the vacuum chamber containing the product, the workpiece air-breaking valve and the chamber air-breaking valve can respond.

[0018] Further, a differential pressure balance valve is provided on the workpiece air-breaking pipeline. The differential pressure balance valve is controlled by the control system. When the control system adjusts the air flow rate during the air-breaking of the product cavity, the differential pressure balance valve can adjust the air flow rate in the workpiece air-breaking pipeline.

[0019] In summary, the technical effects and advantages of the present invention are as follows:

[0020] The present invention can accurately and effectively identify the pressure difference between the product and the vacuum box during the detection process, and can accurately and effectively control the air flow rate during the evacuation and breaking process to ensure that the pressure difference between the product and the vacuum box is always within a safe range, effectively avoiding the phenomenon of dents and bulges caused by the pressure difference not meeting the standards during the leakage detection operation of the product, has a protective effect on thin-walled products, and improves the safety when the vacuum box is opened and the product is taken out. While ensuring the quality of the product and having a protective effect on the product, it effectively improves the safety during the product detection operation. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For those skilled in the art, other drawings can be obtained based on these drawings without paying any creative work.

[0022] Figure 1 It is a schematic diagram of the three-dimensional structure of the present invention.

[0023] Figure 2 It is a schematic diagram of the structure from the second viewing angle of the present invention.

[0024] Figure 3 It is a schematic diagram of the top view structure of the present invention.

[0025] Figure 4 Schematic diagram of the process of this method.

[0026] In the figure: 1. vacuum box; 11. workpiece vacuum regulating valve; 12. box body vacuum regulating valve; 13. workpiece air-breaking valve; 14. box body air-breaking valve; 15. differential pressure balancing valve. DETAILED DESCRIPTION

[0027] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only 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 creative work are within the scope of protection of the present invention.

[0028] Example 1: Reference Figures 1-4 A nondestructive testing method for thin-walled products shown in the figure includes a vacuum box 1 and a product 1 arranged in the vacuum box 1. The nondestructive testing method includes the following steps:

[0029] S1: Detect the wall thickness of Product 1, which is 0.2 mm. Set the pressure difference range between the product and Vacuum Chamber 1 to ≤ 10 Kpa, and import the pressure difference range into the control system.

[0030] S2: Evacuate the product and Vacuum Chamber 1 that holds the product. The pumping speed of the cavity of Product 1 is too fast, resulting in the pressure difference between the product and Vacuum Chamber 1 exceeding the pressure difference range set in Step S1. The control system controls the cavity of Product 1 to suspend the evacuation operation until the pressure difference between the cavity of Product 1 and the cavity of Vacuum Chamber 1 meets the set pressure difference range, and then evacuate the cavity of Product 1 or the cavity of Vacuum Chamber 1 again until the evacuation operation is completed.

[0031] S3: Perform a helium leak detection operation on Product 1.

[0032] S4: Perform a pressure relief operation on Product 1 and Vacuum Chamber 1 that holds Product 1. When the cavity of Vacuum Chamber 1 is quickly depressurized, detect the pressure difference between the cavity of Product 1 and the cavity of Vacuum Chamber 1. If it does not meet the pressure difference range set in Step S1, the control system adjusts the air flow rate during the pressure relief of the cavity of Product 1 until the pressure difference between Product 1 and the vacuum chamber meets the pressure difference range.

[0033] S5: After the detection is completed, open Vacuum Chamber 1 and safely take out Product 1.

[0034] Specifically, in order to perform a leak detection operation on Product 1, Step S3 includes the following steps:

[0035] S31: Fill the workpiece with high-pressure nitrogen. If there is a leakage in the workpiece, helium leaks into the cavity of Vacuum Chamber 1; otherwise, there is no change inside the body of Vacuum Chamber 1.

[0036] S32: The helium detection system connected to Vacuum Chamber 1 detects whether there is leaked helium in the cavity of Vacuum Chamber 1. If there is a helium leakage in the workpiece, the helium detection system transmits a leakage signal to the control system. The control system alarms and marks the leaking Product 1. Otherwise, if there is no helium leakage in the workpiece, the helium detection system transmits the detection result to the control system, and the control system marks Product 1 as qualified.

[0037] S33: Recover the helium inside the workpiece.

[0038] It should be noted that after placing Product 1 in Vacuum Chamber 1 in Step S2, the positioning structure inside Vacuum Chamber 1 needs to be operated to press Product 1 tightly to maintain the stability of Product 1 during the evacuation and pressure relief processes.

[0039] In order to smoothly evacuate and break the vacuum for Product 1 and the vacuum chamber 1, a chamber evacuation pipeline connected to the inside of the chamber and a workpiece evacuation pipeline connected to Product 1 are provided on the vacuum chamber 1. A workpiece evacuation regulating valve 11 and a chamber evacuation regulating valve 12 are respectively provided on the workpiece evacuation pipeline and the chamber evacuation pipeline. When the control system controls the evacuation operation for Product 1 and the vacuum chamber 1 carrying Product 1, the workpiece evacuation regulating valve 11 or the chamber evacuation regulating valve 12 can respond.

[0040] Furthermore, a chamber pressure-breaking pipeline connected to the inside of the chamber and a workpiece pressure-breaking pipeline connected to Product 1 are provided on the vacuum chamber 1. The workpiece pressure-breaking pipeline is connected to the workpiece evacuation pipeline. A workpiece pressure-breaking valve 13 and a chamber pressure-breaking valve 14 are respectively provided on the workpiece pressure-breaking pipeline and the chamber pressure-breaking pipeline. When the control system performs a pressure-breaking operation on Product 1 and the vacuum chamber 1 carrying Product 1, the workpiece pressure-breaking valve 13 and the chamber pressure-breaking valve 14 can respond.

[0041] It should be noted that a differential pressure balance valve 15 is provided on the workpiece pressure-breaking pipeline. The differential pressure balance valve 15 is controlled by the control system. When the control system adjusts the air flow rate during the pressure-breaking of the product cavity, the differential pressure balance valve 15 can adjust the air flow rate in the workpiece pressure-breaking pipeline.

[0042] Embodiment 2: On the basis of Embodiment 1, perform a non-destructive testing operation on Product 2, including the following steps:

[0043] S1: Detect the wall thickness of Product 2, which is 0.25 mm. Set the differential pressure range between the product and the vacuum chamber 1 to ≤14 Kpa, and import the differential pressure range into the control system.

[0044] S2: Perform an evacuation operation on the product and the vacuum chamber 1 carrying the product. The pumping speed of the cavity of Product 2 is too fast, resulting in the differential pressure between the product and the vacuum chamber 1 exceeding the differential pressure range set in step S1. The control system controls the cavity of Product 2 to suspend the evacuation operation until the differential pressure between the cavity of Product 2 and the cavity of the vacuum chamber 1 meets the set differential pressure range, and then perform the evacuation operation on the cavity of Product 2 or the cavity of the vacuum chamber 1 again until the evacuation operation is completed.

[0045] S3: Perform a helium leak detection operation on Product 2.

[0046] S4: Perform a pressure-breaking operation on Product 2 and the vacuum chamber 1 carrying Product 2. When the cavity of the vacuum chamber body 1 quickly completes the pressure-breaking, perform a differential pressure detection on the cavity of Product 2 and the cavity of the vacuum chamber 1. If it does not meet the differential pressure range set in step S1, the control system adjusts the air flow rate during the pressure-breaking of the cavity of Product 2 until the differential pressure between Product 2 and the vacuum chamber meets the differential pressure range;

[0047] S5: After the detection is completed, open the vacuum chamber 1 and safely take out Product 2.

[0048] Example 3: On the basis of Example 1, a non-destructive testing operation is performed on Product Three, including the following steps:

[0049] S1: Detect the wall thickness of Product Three. The wall thickness is 0.35 mm. Set the pressure difference range between the product and Vacuum Chamber 1 to ≤17 Kpa, and import the pressure difference range into the control system.

[0050] S2: Perform a evacuation operation on the product and Vacuum Chamber 1 carrying the product. The pumping speed of the cavity of Vacuum Chamber 1 is too fast, resulting in the pressure difference between the product and Vacuum Chamber 1 exceeding the pressure difference range set in Step S1. The control system controls the cavity of Vacuum Chamber 1 to pause the evacuation operation until the pressure difference between the cavity of Product Three and the cavity of Vacuum Chamber 1 meets the set pressure difference range, and then perform the evacuation operation on the cavity of Product Three or the cavity of Vacuum Chamber 1 again until the evacuation operation is completed.

[0051] S3: Perform a helium leak detection operation on Product Three.

[0052] S4: Perform a pressure relief operation on Product Three and Vacuum Chamber 1 carrying Product Three. The pressure difference between Product Three and Vacuum Chamber 1 always meets the pressure difference range;

[0053] S5: The detection is completed. Open Vacuum Chamber 1 and safely take out Product Three.

[0054] After the detection operation is completed, defect detection is performed on Product One, Product Two, and Product Three in Examples 1-3. There are no dents or bulges in Product One, Product Two, and Product Three, which meet the factory standards of the products.

[0055] Finally, it should be noted that the above are only the preferred embodiments of the present invention and are not used to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, for those skilled in the art, they can still modify the technical solutions described in the foregoing embodiments, or perform equivalent replacements on some of the technical features. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. A non-destructive testing method for thin-walled products, including a vacuum chamber (1) and a product disposed within the vacuum chamber (1), characterized in that, The non-destructive testing method includes the following steps: S1: Detect the wall thickness of the product, set the pressure difference range between the product and the vacuum chamber (1), and import the pressure difference range into the control system; S2: Perform a evacuation operation on the product and the vacuum chamber (1) carrying the product. When the evacuation speed of the product cavity or the vacuum chamber (1) cavity is too fast, resulting in the pressure difference between the product and the vacuum chamber (1) exceeding the pressure difference range set in step S1, the control system controls the product cavity or the vacuum chamber (1) cavity to pause the evacuation operation until the pressure difference between the product cavity and the vacuum chamber (1) cavity meets the set pressure difference range, and then perform the evacuation operation on the product cavity or the vacuum chamber (1) cavity again until the evacuation operation is completed: S3: Perform a helium leak detection operation on the product; S4: Perform a pressure relief operation on the product and the vacuum chamber (1) carrying the product. When the cavity of the vacuum chamber body (1) is quickly depressurized, perform a pressure difference detection on the product cavity and the vacuum chamber (1) cavity. If it does not meet the pressure difference range set in step S1, the control system adjusts the air flow rate during the pressure relief of the product cavity until the pressure difference between the product and the vacuum chamber meets the pressure difference range; S5: After the detection is completed, take out the product.

2. The non-destructive testing method for thin-walled products according to claim 1, characterized in that: The step S3 includes the following steps: S31: Fill the workpiece with high-pressure nitrogen at the same time. If there is a leakage phenomenon in the workpiece, helium leaks into the inside of the vacuum chamber (1) cavity. Otherwise, there is no change inside the vacuum chamber (1) body; S32: The helium detection system connected to the vacuum chamber (1) detects whether there is leaked helium in the vacuum chamber (1) cavity. If there is a helium leakage phenomenon in the workpiece, the helium detection system transmits the leakage signal to the control system, and the control system alarms and marks the leaking product. Otherwise, if there is no helium leakage phenomenon in the workpiece, the helium detection system transmits the detection result to the control system, and the control system marks the product as qualified: S33: Recover the helium in the workpiece.

3. The non-destructive testing method applied to thin-walled products according to claim 1, characterized in that: After the product is placed in the vacuum chamber (1) in step S2, it is necessary to operate the positioning structure inside the vacuum chamber (1) to press the product tightly to maintain the stability of the product during the evacuation and pressure relief processes.

4. The non-destructive testing method applied to thin-walled products according to claim 1, characterized in that: The vacuum chamber (1) is provided with a chamber evacuation pipeline connected to the inside of the chamber and a workpiece evacuation pipeline connected to the product. The workpiece evacuation pipeline and the chamber evacuation pipeline are respectively provided with a workpiece evacuation regulating valve (11) and a chamber evacuation regulating valve (12). When the control system controls the evacuation operation on the product and the vacuum chamber (1) carrying the product, the workpiece evacuation regulating valve (11) or the chamber evacuation regulating valve (12) can respond.

5. The non-destructive testing method applied to thin-walled products according to claim 1, characterized in that: The vacuum chamber (1) is provided with a chamber pressure relief pipeline connected to the inside of the chamber and a workpiece pressure relief pipeline connected to the product. The workpiece pressure relief pipeline is connected to the workpiece evacuation pipeline. The workpiece pressure relief pipeline and the chamber pressure relief pipeline are respectively provided with a workpiece pressure relief valve (13) and a chamber pressure relief valve (14). When the control system performs a pressure relief operation on the product and the vacuum chamber (1) carrying the product, the workpiece pressure relief valve (13) and the chamber pressure relief valve (14) can respond.

6. The non-destructive testing method applied to thin-walled products according to claim 5, characterized in that: A differential pressure balance valve (15) is provided on the air evacuation pipeline of the workpiece. The differential pressure balance valve (15) is controlled by a control system. When the control system adjusts the air flow rate during the air evacuation of the product cavity, the differential pressure balance valve (15) can adjust the air flow rate in the air evacuation pipeline of the workpiece.

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