A detection system and comprehensive evaluation method for marine corrosion prevention duration of protective material

Abstract

The application discloses a kind of detection system and comprehensive evaluation method of marine anti-corrosion duration of protective material, the system includes detection component, for simulating salt fog and mechanical vibration transport environment under marine state;Test tooling is used to simulate the structure of easy rusting part in actual marine process;Environment control component is used to simulate the alternating wet and hot environment and carry out real-time monitoring;Imaging component is used to detect the temperature difference of the surface of the test tooling material, identify the rusting area, and record the earliest rusting time of the test tooling.The test tooling designed by the application covers machine-added surface, bolt, threaded hole through hole, threaded hole blind hole and other easy rusting parts, uses infrared thermal imaging technology to periodically scan the test tooling, identifies the damage point and local early rusting of protective material, comprehensively evaluates the anti-corrosion ability of protection scheme, realizes efficient, quantitative and dynamic anti-corrosion ability evaluation, and provides support for rapid screening and process optimization of protective material and protection scheme in marine scenario.

Description

Technical Field

[0001] This invention belongs to the field of corrosion detection technology for protective materials, and specifically relates to a detection system and comprehensive evaluation method for the corrosion resistance time of protective materials during sea transport. Background Technology

[0002] Sales of construction machinery products in overseas markets have been increasing year by year. However, the problem of rust during the transportation of products by sea is becoming increasingly serious, which increases the cost of maintenance and replacement of parts, and reduces product quality and brand image. Currently, commonly used anti-corrosion and protective materials include rust-preventive oils, rust-preventive waxes, plastic films, heat-shrink films, vapor phase rust inhibitors, varnishes, silver paints, and peelable coatings. Various protective materials are selected based on the structure and corrosion characteristics of the parts of the workpiece to be protected. However, current industry testing methods for the anti-corrosion and protective effects of various materials largely rely on traditional salt spray tests or short-term exposure tests. However, engineering machinery faces multiple corrosion challenges during sea transport: salt spray corrosion, damp heat aging (high temperature and humidity accelerate coating failure), and mechanical vibration (packaging damage leading to localized corrosion). Salt spray tests alone cannot fully simulate the long-term corrosion behavior under the complex environment of sea transport, and can only determine the anti-corrosion performance of one material. In actual sea transport, due to the numerous and varied areas prone to rust, multiple materials are often used simultaneously in different areas. The rusting time and degree of various materials differ under harsh sea transport conditions. Therefore, a single evaluation method easily leads to an incomplete evaluation system for protective materials, and there is a lack of a comprehensive sea transport anti-corrosion duration evaluation method. To address the aforementioned issues, there is an urgent need to develop an objective, easily implementable testing system and evaluation method that can simulate various operating conditions from multiple factors and comprehensively evaluate the corrosion protection duration of different protective materials and solutions during sea transport. This system and method will objectively and accurately assess the protective effect of protective materials on workpieces during actual sea transport.

[0003] Currently, there are few methods for testing and evaluating the corrosion resistance of protective materials during sea transport, both domestically and internationally. Most research focuses on the formulation development of protective materials and the development of corrosion resistance testing equipment. For example, Chinese invention patent CN202410800681.3 discloses a testing device and method for the corrosion resistance of plastic films. However, this method can only test the corrosion resistance of plastic films to corrosive liquids and cannot test the protective performance of materials such as rust-preventive oils. Furthermore, it cannot quantitatively evaluate the corrosion resistance of plastic films, only allowing for horizontal comparisons. Chinese invention patent CN202411118915.2 discloses a rapid evaluation method for the atmospheric corrosion resistance of steel surface protective materials. This method uses a seaside hanging test and a laboratory immersion test chamber to establish a correlation between the two tests using the weight loss rate, enabling rapid evaluation of the corrosion resistance and lifespan prediction of surface protective materials. However, it lacks assessment of early rusting of protective materials and assessment of the degree of corrosion under a given protection and corrosion resistance duration, resulting in incomplete evaluation results. Additionally, the seaside hanging test cycle is too long, and the weight loss rate test process in each cycle is complex. Chinese utility model patent CN202321579794.2 discloses a device for testing the corrosion resistance of rust-preventive oil. This device can only simulate a humid environment. Its focus is on bringing acidic and alkaline liquids into contact with the workpiece coated with rust-preventive oil. It cannot simulate actual maritime environments, resulting in a limited environmental context. Furthermore, it cannot perform accelerated testing and lacks a quantitative and comprehensive evaluation of the corrosion resistance time of various protective materials and solutions. Chinese invention patent CN202121476158.8 discloses a device for rapidly analyzing the rust-preventive performance of rust-preventive oil. This device focuses on increasing the contact area between the sample and salt spray to improve testing efficiency, rather than testing and evaluating the corrosion resistance time of various protective materials. It also cannot simulate maritime environments, leading to discrepancies between the test results and actual application effects. Summary of the Invention

[0004] The technical problem to be solved by this invention is to provide a detection system and comprehensive evaluation method for the corrosion resistance time of protective materials during sea transport. It can simulate the high temperature, high humidity and vibration environment during sea transport, and use salt spray corrosion for accelerated testing. A climate-mechanical composite accelerated testing method has been established.

[0005] To achieve the above objectives, the present invention employs the following technical solution: This invention provides a system for detecting the corrosion resistance time of protective materials during sea transport, comprising: Detection components are used to simulate the salt spray and mechanical vibration transportation environment under maritime conditions; Test fixtures are used to simulate the structure of easily corroded parts during actual sea transport. Environmental control components are used to simulate and monitor hot and humid alternating environments in real time. An imaging component is used to detect the surface temperature difference of the test fixture material, identify the rusted area, and identify and record the earliest rust time of the test fixture. An evaluation board is used to calculate the rust area of ​​the test fixture.

[0006] Preferably, the testing components include a test chamber, a brine tank, a sprayer, a vibration table, and a clamping device; The test chamber is equipped with a water inlet pipe and an exhaust pipe. The water inlet pipe is connected to the brine container tank, and the brine container tank is connected to the sprayer. The brine is pumped from the brine container tank into the sprayer by a corrosion-resistant centrifugal pump. The sprayer is equipped with a spray nozzle at the top to simulate the accelerated corrosion test environment of neutral salt spray. The vibration table is located inside the test chamber and is used to simulate ship vibration. Test fixtures are placed on the vibration table. The clamping device is used to fix the test fixture.

[0007] Preferably, the brine concentration in the brine container is 5±0.1%, and the pH value is 6.5~7.2.

[0008] Preferably, the vibration frequency of the vibration table is set to 10 Hz.

[0009] Preferably, the test fixture has a machined surface, M8 bolts, M16 bolts, threaded through holes and threaded blind holes to simulate the structure of easily corroded parts during actual sea transport.

[0010] Preferably, the environmental control components include a temperature and humidity controller and a temperature and humidity sensor. The temperature and humidity sensor is located inside the test chamber, and the temperature and humidity controller is located outside the test chamber; The temperature and humidity controller is used to regulate the temperature and humidity inside the test chamber to achieve alternating hot and humid cycles.

[0011] Preferably, the imaging component includes: Infrared thermal imaging detectors are used to detect the micro-temperature field thermal distortion caused by corrosion on the surface of test fixtures and convert thermal radiation energy into electrical signals, which are then sent to the infrared thermal imaging processor. An infrared thermal imaging optical system is used to control the incident angle and flux of infrared radiation so that the target energy is focused onto the infrared thermal imaging detector. The scanning lens is used to achieve 0°~360° panoramic scanning through a rotating prism and send the scanning data to the infrared thermal imaging processor. Infrared thermal imaging processor for constructing corrosion thermal sequence maps; The infrared thermal imaging processor is connected to the display screen via a signal transmission line; The display screen is used to display thermal imaging images of rust and temperature and humidity information inside the test chamber.

[0012] Preferably, the evaluation board is a colorless and transparent flat plate with a size of 120mm×120mm and an effective testing area of ​​100mm×100mm. 400 grids of 5mm×5mm are engraved within the effective testing area, with a grid line width of 0.5mm.

[0013] This invention also provides a method for detecting and comprehensively evaluating the corrosion resistance time of protective materials during sea transport, based on the aforementioned detection system for the corrosion resistance time of protective materials during sea transport. The method includes: Pre-process the test fixtures; The protective parts of the pre-treated test fixture are classified and protected accordingly; Conduct marine simulated accelerated corrosion tests to monitor and record the earliest rust time of each protected part; After the test is completed, the rust area is calculated; The corrosion protection index of each protected part is calculated based on the rust area and the earliest rust time. A comprehensive evaluation of the overall protection scheme's protection index is conducted based on the corrosion protection index of each protected component.

[0014] Preferably, the preprocessing of the test fixture includes: The test fixture is polished and cleaned to ensure that there is no rust or dust on the surface of the fixture and inside the threaded through holes and threaded blind holes.

[0015] Preferably, the step of classifying and protecting the various protective parts of the pre-treated test fixture includes: Based on the product's sea transport requirements and the characteristics of various packaging and protective materials, rust-preventive oil, rust-preventive wax, vapor phase rust inhibitor film, heat shrink film, or polyethylene plastic film are selected to protect the bolts, machined surfaces, threaded through holes, and threaded blind holes on the test fixture.

[0016] Preferably, the step of conducting a simulated accelerated corrosion test during sea transport, and monitoring and recording the earliest rust time of each protected part, includes: The protected test fixture was placed on the vibration table inside the test chamber. The temperature and humidity inside the test chamber were adjusted, and the vibration and salt spray were turned on to conduct a simulated accelerated corrosion test in the sea. Perform thermal imaging scanning of the test fixture, observe and record the test time at which the earliest rust appeared on each protected part, and record it as t0; After the predetermined test time, turn off the vibration table and salt spray, and record the test time as t.

[0017] Preferably, the adjustment of temperature and humidity inside the test chamber includes: Adjust the temperature inside the test chamber to 49℃±2℃ and the humidity to greater than 95%RH.

[0018] Preferably, the thermal imaging scan of the test fixture includes: Thermal imaging scans of the test fixtures are performed every 12 hours.

[0019] Preferably, the calculation of the rust area includes: The evaluation board is superimposed on the surface of the test fixture. A rusted area exceeding half the area of ​​a 5mm × 5mm square is considered a complete defect; if it is less than half the area of ​​a 5mm × 5mm square, it is considered a 1 / 3 defect. The rusted area of ​​each protected area is recorded as A. c The total test area for each protected part is recorded as A. t .

[0020] Preferably, the calculation of the corrosion protection index for each protected part based on the rust area and the earliest rust time includes: PPI=0.4(t0 / t)+0.6(1- A c / A t ), Where: PPI is the corrosion protection index, t0 is the test duration when the protected part first shows rust, and t is the total test duration.

[0021] Preferably, the comprehensive evaluation of the overall protection scheme's protection index based on the corrosion protection index of each protected part includes: The Composite Protection Effectiveness Index (CPEI) is calculated as follows: CPEI=∑[α i * PPI i ], Where: α i PPI is the importance coefficient of the protected part i. i The corrosion protection index of protected part i; If CPEI ≥ 85, the protection solution is excellent; If the CPEI is 60~85, there is a risk of large-area corrosion, and some protective materials need to be replaced. If CPEI < 60, the protection plan is unqualified and needs to be redesigned.

[0022] The beneficial effects of this invention are: (1) The composite test environment of the present invention, which combines salt spray, humid heat alternating cycle and mechanical vibration, can simulate the accelerated corrosion test environment of the actual sea transport process, which is closer to the actual application environment and ensures the authenticity of the failure mechanism (vibration load causes salt spray to penetrate into the thread gap, which can simulate crevice corrosion failure; humid heat alternating cycle triggers the expansion-contraction stress of the protective material, exposing dynamic failures such as peeling of anti-rust wax and rupture of vapor phase anti-rust film), realizes the dynamic simulation of the real sea transport environment, which is closer to the actual use conditions, and the test results are more reliable and applicable.

[0023] (2) This invention utilizes the principle of infrared thermal imaging to detect the temperature difference on the surface of materials, which can dynamically capture local early corrosion, quickly identify corrosion areas, and be used to monitor and record the earliest corrosion time of the test fixture, thereby improving detection sensitivity and avoiding the tediousness and errors of manual periodic observation.

[0024] (3) The test tooling design of this invention includes the structure of parts of the product that are prone to corrosion during sea transport, such as machined surfaces, bolts, threaded through holes, and threaded blind holes, and the test results are more comprehensive.

[0025] (4) This invention develops a comprehensive evaluation method for the corrosion protection duration of protective materials during sea transport. It uses the corrosion protection index (PPI) of a single protective material and the composite protection effectiveness index (CPEI) of the overall protection scheme for comprehensive evaluation. The evaluation dimensions are more comprehensive and the evaluation results are more applicable and instructive. Attached Figure Description

[0026] Figure 1 A schematic diagram of the process for detecting and comprehensively evaluating the corrosion resistance time of protective materials during sea transport, provided in an embodiment of the present invention; Figure 2 This is a schematic diagram of a system for detecting the corrosion resistance time of protective materials during sea transport, provided in an embodiment of the present invention. Figure 3 This is a schematic diagram of the test fixture provided in an embodiment of the present invention; Figure 4 This is a schematic diagram of an evaluation board provided in an embodiment of the present invention. Detailed Implementation

[0027] The specific embodiments of the present invention will be described in further detail below with reference to the accompanying drawings and examples. The embodiments described below with reference to the accompanying drawings are illustrative and intended to explain the present invention, and should not be construed as limiting the present invention.

[0028] In the description of this invention, it should be noted that the terms "upper", "lower", "front", "rear", "end", "bottom", "side", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or component referred to must have a specific orientation. Therefore, they should not be construed as limiting this invention.

[0029] In this invention, unless otherwise explicitly specified and limited, the terms "connection," "installation," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a direct connection, or a connection through an intermediate medium. Those skilled in the art can understand the specific meaning of these terms in this invention according to the specific circumstances.

[0030] Secondly, the term "an embodiment" or "embodiment" as used in this invention refers to a specific feature, structure, or characteristic that can be included in at least one implementation of this invention. The phrase "in one embodiment" appearing in different places in this specification does not necessarily refer to the same embodiment, nor is it a single or selective embodiment that excludes other embodiments.

[0031] The specific embodiments of the present invention will be described in further detail below with reference to the accompanying drawings. The following examples are for illustrative purposes only and are not intended to limit the scope of the invention.

[0032] This invention provides, on the one hand, a system for detecting the corrosion protection duration of protective materials during sea transport. This system simulates the actual transportation environment of sea transport, including salt spray, alternating wet and hot cycles, and mechanical vibration, to detect and monitor the corrosion protection duration of protective materials during early corrosion. On the other hand, this invention presents a comprehensive evaluation method for the corrosion protection duration of protective materials during sea transport. It utilizes a weighted fusion of early corrosion time and corrosion rate, and the importance of the protected area, to construct a comprehensive evaluation model for the corrosion protection index of protective materials. This addresses the problem that the effectiveness of protective materials and solutions relies primarily on actual sea transport experience, making evaluation and prediction difficult. It achieves dynamic threshold early warning for sea transport protection solutions, improving the efficiency of selecting protective materials and solutions, and resolving the issue that the effectiveness of protective materials and solutions relies primarily on actual sea transport experience, making evaluation and prediction difficult.

[0033] See Figure 2 The present invention provides a detection system for the corrosion resistance time of protective materials during sea transport, including a detection component 1, a testing fixture 10, an imaging component 14, an environmental control component 11, and an evaluation plate.

[0034] In this invention, the testing component 1 includes a test chamber 2, a brine container 3, a sprayer 4, a spray nozzle 5, a water inlet pipe 6, an exhaust pipe 7, a vibration table 8, and a clamping device 9. The testing component 1 is used to simulate the salt spray and mechanical vibration transportation environment under sea transport conditions.

[0035] Specifically, the test chamber 2 is equipped with a water inlet pipe 6 and an exhaust pipe 7. The water inlet pipe 6 is connected to the brine container 3, and the brine container 3 is connected to the sprayer 4. The brine is pumped directly from the brine container 3 into the sprayer 4 through a corrosion-resistant centrifugal pump. The sprayer 4 is equipped with a spray nozzle 5 on top.

[0036] The brine concentration in the brine container 3 is 5±0.1%, and the pH value is 6.5~7.2, which is used to simulate the accelerated corrosion test environment of neutral salt spray.

[0037] The test chamber 1 is equipped with a vibration table 8, with a vibration frequency set to 10 Hz to simulate the vibration frequency of the ship hull. Test fixtures 10 can be placed on the vibration table 8.

[0038] The vibration table 8 is equipped with a clamping device 9 for fixing the test fixture 10.

[0039] See Figure 3 In this invention, the test fixture 10 has a structure with a machined surface ①, an M8 bolt ②, an M16 bolt ③, a threaded through hole ④, and a threaded blind hole ⑤, which is used to simulate the structure of easily corroded parts during actual sea transport.

[0040] In this invention, the environmental control component 11 includes a temperature and humidity controller 12 and a temperature and humidity sensor 13. The temperature and humidity sensor 13 is located inside the test chamber 2, and the temperature and humidity controller 12 is located outside the test chamber 2.

[0041] The temperature and humidity controller 12 is used to regulate the temperature and humidity inside the test chamber 2, realize the alternating cycle of heat and humidity and monitor it in real time. The temperature and humidity can be set according to the marine atmospheric temperature and humidity conditions in different seasons.

[0042] In this invention, the imaging component 14 includes an infrared thermal imaging processor 15, an infrared thermal imaging detector 16, an infrared thermal imaging optical system 17, a scanning lens 18, a signal transmission line 19, and a display screen 20.

[0043] Specifically, the infrared thermal imaging processor 15 is connected to an infrared thermal imaging detector 16, which is used to detect the micro-temperature field thermal distortion caused by corrosion on the surface of the tooling and convert thermal radiation energy into electrical signals; the infrared thermal imaging optical system 17 is used to adjust the incident angle and flux of infrared radiation so that the target energy is efficiently focused to the infrared thermal imaging detector 16; the scanning lens 18 is used for dynamic field coverage and spatial sampling, and achieves 0°~360° panoramic scanning through rotating prism, and matches the frame rate with the infrared thermal imaging detector 16 to realize the construction of corrosion thermal sequence map; all of the above are set on the top of the test chamber 2. The infrared thermal imaging processor 15 uses thermal imaging technology to detect the surface temperature difference of the test tooling 10, quickly identify the corrosion area, identify and record the earliest corrosion time of the test tooling, avoiding the tediousness and error of manual periodic observation.

[0044] The infrared thermal imaging processor 15 is connected to the display screen 20 via the signal transmission line 19. The display screen 20 is used to display thermal images and information such as temperature and humidity inside the test chamber.

[0045] See Figure 4 In this invention, the evaluation board is a colorless and transparent flat plate with a size of 120mm×120mm and an effective testing area of ​​100mm×100mm. 400 grids of 5mm×5mm are engraved within the effective testing area, with a grid width of 0.5mm.

[0046] Based on the aforementioned detection system for the corrosion resistance duration of protective materials during sea transport, this invention also provides a comprehensive evaluation method for the corrosion resistance duration of protective materials during sea transport. (See [link to relevant documentation]). Figure 1 ,include: The process involves pre-treating the test fixtures, classifying and protecting each part of the test fixtures, conducting marine simulated accelerated corrosion tests, monitoring and recording the earliest rust time of each part, calculating the rust area, calculating the corrosion protection index of each part, and comprehensively evaluating the overall protection scheme's protection index.

[0047] The specific implementation process of the above comprehensive evaluation method is as follows: (1) Grind and clean the test fixture to ensure that there is no rust or dust on the surface of the fixture and inside the threaded through holes and threaded blind holes.

[0048] (2) Use an electric wrench to tighten and fix the M8 and M16 bolts to the test fixture. The M8 bolts should be tightened to a torque of 35 N·m ~ 45 N·m, and the M16 bolts should be tightened to a torque of 330 N·m ~ 360 N·m.

[0049] (3) Based on the product's sea transport requirements and the characteristics of various packaging and protective materials, rust-preventive oil, rust-preventive wax, vapor phase rust-preventive film, heat shrink film, polyethylene plastic film and other materials are selected to protect the bolts, machined surfaces, threaded through holes and threaded blind holes on the test fixture.

[0050] (4) Place the protected test fixture into the vibration table in the test chamber, fix it with the clamping device, adjust the temperature in the test chamber to 49℃±2℃, set the humidity to greater than 95%RH, turn on the vibration table and salt spray, and carry out the marine simulated accelerated corrosion test.

[0051] (5) Click the scan button on the display screen every 12 hours to perform thermal imaging scanning of the test fixture through the imaging component, observe and record the test time when the earliest rust appears on each protected part, and record it as t0.

[0052] (6) After the test reaches the predetermined time, turn off the vibration table and the salt sprayer, and record the test time as t.

[0053] (7) Remove the test fixture, remove the protective packaging, clean the surface rust products, and use the evaluation plate to test the rust area on the machined surface and other planar locations. Use an industrial endoscope with built-in calibration and measurement functions to measure the rust area at the threaded hole location. Overlap the evaluation plate with the surface of the test fixture. A rust area exceeding half the area of ​​a 5mm × 5mm square is considered a complete defect. If it is less than half the area of ​​a 5mm × 5mm square, it is considered a 1 / 3 defect. The rust area of ​​each protected part is recorded as A. c The total test area for each protected part is recorded as A. t .

[0054] (8) The corrosion protection index (PPI) of various parts such as computer-aided surfaces, bolts, threaded through holes, and threaded blind holes is calculated. The weighted proportion of the earliest corrosion time is set to 0.4, and the weighted proportion of corrosion area is set to 0.6. The formula for calculating the corrosion protection index (PPI) is as follows: PPI=0.4(t0 / t)+0.6(1- A c / A t ), Where: t0 is the test duration when rust first appears on each protected part; t is the total test duration; A c The rust area for each protected part; A t Test the total area for each protected area.

[0055] (9) Assign importance coefficients α to machined surfaces, bolts, threaded through holes, and threaded blind holes from the perspectives of failure risk level, appearance importance, and maintenance cost. i The overall protection plan's marine protection duration is comprehensively evaluated by weighting the corrosion protection levels of each component. Importance coefficients are assigned within a given range based on the varying degrees of importance of each protected component to different products, with the sum of all importance coefficients not exceeding 100. The Composite Protection Effectiveness Index (CPEI) is calculated using the following formula, incorporating both the importance coefficient of the protected component and the corrosion protection index. A CPEI ≥ 85 indicates an excellent protection plan; a CPEI between 60 and 85 indicates a risk of large-area corrosion, requiring replacement of some protective materials; and a CPEI < 60 indicates an unqualified protection plan, requiring a revised plan.

[0056] CPEI=∑[α i * PPI i ], Where: α i The importance coefficient for protected part i is shown in Table 1 below; PPI i The corrosion protection index of protected part i is relative to the importance coefficient.

[0057] Table 1 Importance coefficient of the area to be protected

[0058] Based on the above technical means, the present invention provides a detection system and comprehensive evaluation method for the sea-going corrosion protection time of protective materials, which is realistic, comprehensive and intuitive. The testing system and evaluation method have the advantages of being simple and easy to implement, and can realize a comprehensive and objective evaluation of the sea-going corrosion protection time of protective materials.

[0059] It should be noted that the above-mentioned marine environment simulation factors and easily corroded structural forms are typical cases of engineering machinery products during marine transportation, and are not intended to limit the patent scope of this invention. Furthermore, any addition of test items or protective parts, changes in the importance coefficient of the items, changes in the weighting ratio, and other equivalent changes that apply the spirit of this invention's patent in the evaluation method should all fall within the patent scope of this invention.

[0060] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the technical principles of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A method for detecting and comprehensively evaluating the corrosion resistance time of protective materials during sea transport, characterized in that, include: Pre-process the test fixtures; The protective parts of the pre-treated test fixture are classified and protected accordingly; Conduct marine simulated accelerated corrosion tests to monitor and record the earliest rust time of each protected part; After the test is completed, the rust area is calculated; The corrosion protection index of each protected part is calculated based on the rust area and the earliest rust time. A comprehensive evaluation of the overall protection scheme's protection index is conducted based on the corrosion protection index of each protected component. The detection and comprehensive evaluation method is implemented through a detection system, which includes: Detection components are used to simulate the salt spray and mechanical vibration transportation environment under maritime conditions; Test fixtures are used to simulate the structure of easily corroded parts during actual sea transport. Environmental control components are used to simulate and monitor hot and humid alternating environments in real time. An imaging component is used to detect the surface temperature difference of the test fixture material, identify the rusted area, and identify and record the earliest rust time of the test fixture. An evaluation board is used to calculate the rust area of ​​the test fixture. The imaging component includes: Infrared thermal imaging detectors are used to detect the micro-temperature field thermal distortion caused by corrosion on the surface of test fixtures and convert thermal radiation energy into electrical signals, which are then sent to the infrared thermal imaging processor. An infrared thermal imaging optical system is used to control the incident angle and flux of infrared radiation so that the target energy is focused onto the infrared thermal imaging detector. The scanning lens is used to achieve 0°~360° panoramic scanning through a rotating prism and send the scanning data to the infrared thermal imaging processor. Infrared thermal imaging processor for constructing corrosion thermal sequence maps; The infrared thermal imaging processor is connected to the display screen via a signal transmission line; The display screen is used to display thermal imaging images of rust and temperature and humidity information inside the test chamber. The calculation of the rust area includes: The evaluation plate is superimposed on the surface of the test fixture. A rusted area exceeding half the area of ​​a 5mm × 5mm square is considered a complete defect; if it is less than half the area of ​​a 5mm × 5mm square, it is considered a 1 / 3 defect. The rusted area of ​​each protected area is recorded as A. c The total test area for each protected part is recorded as A. t ; The calculation of the corrosion protection index for each protected part based on the rust area and the earliest rust time includes: PPI=0.4(t0 / t)+0.6(1- A c / A t ), Where: PPI is the corrosion protection index, t0 is the test duration when the earliest rust appears on the protected part, and t is the total test duration; The comprehensive evaluation of the overall protection scheme based on the corrosion protection index of each protected part includes: The Composite Protection Effectiveness Index (CPEI) is calculated as follows: CPEI=∑[α i * PPI i ], Where: α i Assigning importance coefficients α to the machined surfaces, bolts, threaded through holes, and threaded blind holes based on failure risk level, appearance importance, and maintenance cost. i PPI i The corrosion protection index of protected part i; If CPEI ≥ 85, the protection solution is excellent; If the CPEI is 60~85, there is a risk of large-area corrosion, and some protective materials need to be replaced. If CPEI < 60, the protection plan is unqualified and needs to be redesigned.

2. The method for detecting and comprehensively evaluating the corrosion resistance time of protective materials during sea transport according to claim 1, characterized in that, The preprocessing of the test fixture includes: The test fixture is polished and cleaned to ensure that there is no rust or dust on the surface of the fixture and inside the threaded through holes and threaded blind holes.

3. The method for detecting and comprehensively evaluating the corrosion resistance time of protective materials during sea transport according to claim 1, characterized in that, The process of classifying and protecting each protective component of the pre-treated test fixture includes: Based on the product's sea transport requirements and the characteristics of various packaging and protective materials, rust-preventive oil, rust-preventive wax, vapor phase rust inhibitor film, heat shrink film, or polyethylene plastic film are selected to protect the bolts, machined surfaces, threaded through holes, and threaded blind holes on the test fixture.

4. The method for detecting and comprehensively evaluating the corrosion resistance time of protective materials during sea transport according to claim 1, characterized in that, The aforementioned marine simulated accelerated corrosion test was conducted to monitor and record the earliest rust time of each protected part, including: The protected test fixture was placed on the vibration table inside the test chamber. The temperature and humidity inside the test chamber were adjusted, and the vibration and salt spray were turned on to conduct a simulated accelerated corrosion test in the sea. Perform thermal imaging scanning of the test fixture, observe and record the test time at which the earliest rust appeared on each protected part, and record it as t0; After the predetermined test time, turn off the vibration table and salt spray, and record the test time as t.

5. The method for detecting and comprehensively evaluating the corrosion resistance time of protective materials during sea transport according to claim 4, characterized in that, The adjustment of temperature and humidity inside the test chamber includes: Adjust the temperature inside the test chamber to 49℃±2℃ and the humidity to greater than 95%RH.

6. The method for detecting and comprehensively evaluating the corrosion resistance time of protective materials during sea transport according to claim 4, characterized in that, The thermal imaging scan of the test fixture includes: Thermal imaging scans of the test fixtures are performed every 12 hours.

7. The method for detecting and comprehensively evaluating the corrosion resistance time of protective materials during sea transport according to claim 1, characterized in that, The testing components include a test chamber, a saline solution tank, a sprayer, a vibration table, and a clamping device; The test chamber is equipped with a water inlet pipe and an exhaust pipe. The water inlet pipe is connected to the brine container tank, and the brine container tank is connected to the sprayer. The brine is pumped from the brine container tank into the sprayer by a corrosion-resistant centrifugal pump. The sprayer is equipped with a spray nozzle at the top to simulate the accelerated corrosion test environment of neutral salt spray. The vibration table is located inside the test chamber and is used to simulate ship vibration. Test fixtures are placed on the vibration table. The clamping device is used to fix the test fixture.

8. The method for detecting and comprehensively evaluating the corrosion resistance time of protective materials during sea transport according to claim 7, characterized in that, The brine concentration in the brine container is 5±0.1%, and the pH value is 6.5~7.

2.

9. The method for detecting and comprehensively evaluating the corrosion resistance time of protective materials during sea transport according to claim 7, characterized in that, The vibration frequency of the vibration table is set to 10 Hz.

10. The method for detecting and comprehensively evaluating the corrosion resistance time of protective materials during sea transport according to claim 7, characterized in that, The test fixture features machined surfaces, M8 bolts, M16 bolts, threaded through holes, and threaded blind holes, designed to simulate the structure of easily corroded parts during actual sea transport.

11. The method for detecting and comprehensively evaluating the corrosion resistance time of protective materials during sea transport according to claim 7, characterized in that, The environmental control components include a temperature and humidity controller and a temperature and humidity sensor. The temperature and humidity sensor is located inside the test chamber, and the temperature and humidity controller is located outside the test chamber; The temperature and humidity controller is used to regulate the temperature and humidity inside the test chamber to achieve alternating hot and humid cycles.

12. The method for detecting and comprehensively evaluating the corrosion resistance time of protective materials during sea transport according to claim 7, characterized in that, The evaluation board is a colorless and transparent flat plate with a size of 120mm×120mm. The effective testing area is 100mm×100mm, and 400 grids of 5mm×5mm are engraved within the effective testing area, with a grid width of 0.5mm.

Images