Test design method for evaluating service life of typical structure of ship

Abstract

The invention discloses a test design method for evaluating the service life of a typical structure of a ship, and the method comprises the steps: firstly determining an acceleration test spectrum block which is composed of a temperature and humidity exposure test, an ultraviolet radiation test and a salt spray test; then determining test parameters, wherein the test parameters of the temperature and humidity exposure test comprise temperature, humidity and temperature and humidity exposure action time; test parameters of the ultraviolet irradiation test comprise temperature, ultraviolet irradiation intensity and ultraviolet irradiation time; the test parameters of the salt spray test comprise temperature, salt spray action time, acidic salt spray composition, acidic salt spray pH value, acidic salt spray action time and salt spray settling volume; the temperature and humidity exposure test, the ultraviolet radiation test and the salt spray test are sequentially performed and circulated. The method can accelerate the service life evaluation and prediction of the typical structure of the ship, guarantees the development progress of the ship, and improves the environmental adaptability level.

Description

Technical Field

[0001] The invention belongs to the technical field of ship structure life, and in particular relates to an experimental design method for evaluating the life of a typical ship structure. Background Art

[0002] Ships have been serving in the marine environment for a long time. Their service environment is relatively harsh. They have been in a marine environment with high temperature, high humidity, high salinity, and long-term ultraviolet radiation. In particular, the decks and their superstructures are subject to direct sunlight, salt spray, splashing seawater, and dry / wet alternating cycles. The corrosion problem cannot be ignored and is related to the safety of carrier-based aircraft. Since the natural aging test cycle is too long, in order to quickly determine the corrosion effect of the natural environment on the external typical structure, it is necessary to establish an equivalent relationship between the natural environment spectrum and the laboratory accelerated environment spectrum. In this way, the corrosion damage law of the typical external structure of the ship in the service environment can be obtained in a relatively short time, and the service life of the typical structure can be evaluated and predicted. At present, there is still a blank in the field of experimental technology for ship structure life evaluation and prediction in China. Summary of the invention

[0003] Purpose of the Invention

[0004] In order to realize the life assessment and prediction of ship structures, the present invention provides a test method for life assessment of typical ship structures.

[0005] Inventing technical solutions

[0006] An experimental design method for life assessment of typical ship structures includes the following steps:

[0007] (1) Determination of the accelerated test spectrum block, which consists of temperature and humidity exposure test, ultraviolet irradiation test and salt spray test;

[0008] (2) Determination of test parameters. The test parameters of the temperature and humidity exposure test include temperature, humidity, and temperature and humidity exposure time; the test parameters of the ultraviolet irradiation test include temperature, ultraviolet radiation intensity, and ultraviolet irradiation time; the test parameters of the salt spray test include temperature, salt spray exposure time, acid salt spray composition, acid salt spray pH value, acid salt spray exposure time, and salt spray deposition;

[0009] (3) Carry out the tests in the order of temperature and humidity exposure test, ultraviolet irradiation test and salt spray test and cycle them.

[0010] Preferably, the method is based on the marine atmospheric environment spectra of the Bohai Sea, the East China Sea and the South China Sea.

[0011] Preferably, the temperature of the temperature and humidity exposure test refers to the temperature value in the environmental spectrum of the accelerated corrosion test for exposed parts of the aircraft, and the humidity refers to the humidity value in the environmental spectrum of the accelerated corrosion test for exposed parts of the aircraft.

[0012] Preferably, the temperature and humidity exposure time is calculated according to the following formula:

[0013]

[0014] Where: T is the time that the external structure of the ship is exposed to humid air in one year; T C This is the typical aircraft humid air exposure time.

[0015] Preferably, the temperature in the ultraviolet irradiation test refers to the temperature value in the environmental spectrum of the accelerated corrosion test for exposed parts of the aircraft, and the ultraviolet irradiation intensity refers to the irradiation intensity in the environmental spectrum of the accelerated corrosion test for exposed parts of the aircraft.

[0016] Preferably, the ship ultraviolet irradiation time t is calculated according to the following formula:

[0017]

[0018] Where: Q Z is the amount of ultraviolet radiation received by the external structure of the ship in one year; W is the radiation intensity of the ultraviolet radiation test chamber.

[0019] Preferably, the temperature in the salt spray test refers to the salt spray test temperature, the salt spray test standard and the temperature value in the environmental spectrum of the accelerated corrosion test of the exposed parts of the aircraft; the composition of the acidic salt spray refers to the pH value and ion composition of the water film on the surface of the exposed parts of the aircraft; the pH value of the acidic salt spray refers to the pH value of the acidic salt spray in the three-protection test of the exposed parts of the aircraft; the salt spray deposition amount refers to "GJB 150.11A-2009 Military Equipment Laboratory Environmental Test Method".

[0020] Preferably, the ship salt spray exposure time t is calculated according to the following formula:

[0021]

[0022] Where: T' is the total time that the ship's external structure is exposed to salt spray in one year; T Y This is the typical aircraft salt spray exposure time.

[0023] Preferably, the ratio of the salt spray action time to the acid salt spray action time is determined according to the ratio of the service time and the berthing time of the ship.

[0024] Preferably, the acidic salt spray is prepared by adding dilute H 2 SO 4 5% NaCl solution.

[0025] Advantages of the present invention: The present invention can be used for environmental testing and assessment of typical ship structures. By reasonably adjusting the environmental test conditions and using existing standard environmental equipment, long solar radiation, high humidity, high salt fog environmental tests can be completed, thereby accelerating the evaluation and prediction of the life of typical ship structures, ensuring the development progress of ships, and improving the level of environmental adaptability. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 The process diagram of the typical ship structure life assessment test method of the embodiment is shown. DETAILED DESCRIPTION

[0027] The present invention is achieved through the following technical solutions.

[0028] In view of this, the present invention is based on the marine atmospheric environment spectra of Bohai Sea, East China Sea and South China Sea, selects typical external structures of ships as research objects, and gives a method for determining the parameters of its accelerated environmental test module, as well as the relationship between the accelerated environmental test and the actual environment.

[0029] A test design method for life assessment of typical ship structures, including:

[0030] Determination of accelerated test spectrum blocks

[0031] In view of the characteristics of the service environment of ships, considering that the main influencing factors of the failure of typical external structural coatings are salt spray, high temperature and high humidity environment in the marine atmospheric environment, and ultraviolet rays in the sun, its accelerated environmental spectrum is composed of three spectrum blocks, namely temperature and humidity exposure test, ultraviolet irradiation test and salt spray test.

[0032] Determination of test parameters

[0033] 1) Temperature and humidity exposure test

[0034] a) Temperature conditions

[0035] Referring to the temperature value in the accelerated corrosion test environment spectrum of the exposed parts of the aircraft, take T = 43°C.

[0036] b) Humidity conditions

[0037] Take the humidity value in the accelerated corrosion test environment spectrum of the exposed parts of the aircraft, that is, RH = 95%.

[0038] c) Temperature and humidity exposure time

[0039] The ship temperature and humidity exposure time t is calculated according to the following formula:

[0040]

[0041] Where:

[0042] T is the time the ship's external structure is exposed to humid air in one year.

[0043] T C ——Typical aircraft humid air exposure time.

[0044] 2) UV irradiation test

[0045] a) Temperature conditions

[0046] Refer to the temperature value in the accelerated corrosion test environment spectrum of the exposed parts of the aircraft, that is, T = 55°C.

[0047] b) Ultraviolet radiation intensity

[0048] The irradiation intensity in the accelerated corrosion test environment spectrum of the aircraft exposed parts is W = (60 ± 10) W / m 2 .

[0049] c) Calculation of UV exposure time

[0050] The ship's ultraviolet radiation time t is calculated according to the following formula:

[0051]

[0052] Where:

[0053] Q Z ——The amount of ultraviolet radiation received by the external structure of a ship in one year.

[0054] W——Radiation intensity of ultraviolet radiation test chamber.

[0055] 3) Salt spray test environmental conditions

[0056] a) Temperature conditions

[0057] The salt spray test temperature refers to the salt spray test standard and the accelerated corrosion test environment spectrum of aircraft exposed parts, and T=35℃ is taken.

[0058] b) Salt spray exposure time

[0059] The salt spray action time t of ships is calculated according to the following formula:

[0060]

[0061] Where:

[0062] T'——Total time that the ship's external structure is exposed to salt spray in one year.

[0063] T Y ——Typical aircraft salt spray exposure time.

[0064] c) Acidic salt spray effect

[0065] (1) Composition of acidic salt spray

[0066] Referring to the pH value and ion composition of the water film on the surface of the exposed parts of the aircraft, dilute H 2 SO 4 To reproduce the effects of chemical factors.

[0067] (2) pH value of acidic salt spray

[0068] The pH value of the acidic salt spray test solution for the three-protection test of the exposed parts of the aircraft is determined to be 3.5-4.0, and the pH value of the acidic salt spray test solution is determined to be 3.5-4.0.

[0069] (3) Acid salt spray exposure time

[0070] The time ratio of neutral and acid salt spray depends on the time ratio of the ship in service and at anchor.

[0071] d) Salt spray deposition

[0072] According to the "GJB 150.11A-2009 Military Equipment Laboratory Environmental Test Method Part 11: Salt Spray Test", the salt spray deposition is determined to be (1-3) mL / h·80 cm 2 .

[0073] Taking the formulation of the accelerated environmental test method for a typical structure on a certain type of ship flight deck as an example, the specific formulation of its life assessment test method is as follows:

[0074] 1) Temperature and humidity exposure test

[0075] a) Temperature conditions

[0076] Referring to the temperature value in the accelerated corrosion test environment spectrum of the exposed parts of the aircraft, take T = 43°C.

[0077] b) Humidity conditions

[0078] Take the humidity value in the accelerated corrosion test environment spectrum of the exposed parts of the aircraft, that is, RH = 95%.

[0079] c) Temperature and humidity exposure time

[0080] The ship temperature and humidity exposure time t is calculated according to the following formula:

[0081]

[0082] Where:

[0083] T is the time the ship's external structure is exposed to humid air in one year.

[0084] T C——Typical aircraft humid air exposure time.

[0085] By looking up relevant data and calculating, it can be found that the action time of the temperature and humidity exposure environment block is 13 days.

[0086] d) Wet heat exposure test parameters

[0087] Test temperature: 43°C;

[0088] Test humidity: 95%;

[0089] Test duration: 13 days.

[0090] 2) UV irradiation test

[0091] a) Temperature conditions

[0092] Refer to the temperature value in the accelerated corrosion test environment spectrum of the exposed parts of the aircraft, that is, T = 55°C.

[0093] b) Ultraviolet radiation intensity

[0094] The irradiation intensity in the accelerated corrosion test environment spectrum of the aircraft exposed parts is W = (60 ± 10) W / m 2 .

[0095] c) Calculation of UV exposure time

[0096] The ship's ultraviolet radiation time t is calculated according to the following formula:

[0097]

[0098] Where:

[0099] Q Z ——The amount of ultraviolet radiation received by the external structure of a ship in one year.

[0100] W——Radiation intensity of ultraviolet radiation test chamber.

[0101] The radiation intensity of the UV radiation test chamber is 60W / m 2 , and the ultraviolet irradiation time of typical ship structures is obtained to be 17 days.

[0102] d) Ultraviolet radiation test parameters

[0103] Test temperature: T = 55 ° C;

[0104] Radiation intensity: W = (60 ± 10) W / m 2 ;

[0105] Radiation duration: 17 days.

[0106] 3) Salt spray test environmental conditions

[0107] a) Temperature conditions

[0108] The salt spray test temperature refers to the salt spray test standard and the accelerated corrosion test environment spectrum of aircraft exposed parts, and T=35℃ is taken.

[0109] b) Salt spray exposure time

[0110] The salt spray action time t of ships is calculated according to the following formula:

[0111]

[0112] Where:

[0113] T is the total time that the ship's external structure is exposed to salt spray in one year.

[0114] T Y ——Typical aircraft salt spray exposure time.

[0115] Calculation shows that the salt spray exposure time is 11 days.

[0116] c) Acidic salt spray effect

[0117] (1) Composition of acidic salt spray

[0118] Referring to the pH value and ion composition of the water film on the surface of the exposed parts of the aircraft, dilute H 2 SO 4 To reproduce the effects of chemical factors.

[0119] (2) pH value of acidic salt spray

[0120] The pH value of the acidic salt spray test solution for the three-protection test of the exposed parts of the aircraft is determined to be 3.5-4.0, and the pH value of the acidic salt spray test solution is determined to be 3.5-4.0.

[0121] (3) Acid salt spray exposure time

[0122] The time ratio of neutral and acidic salt spray depends on the time ratio of the ship's service and anchoring. According to the ratio of the ship's sailing and anchoring time being 1:1, the corresponding neutral and acidic salt spray action time can be 5.5 days and 5.5 days respectively.

[0123] d) Salt spray deposition

[0124] According to the "GJB 150.11A-2009 Military Equipment Laboratory Environmental Test Method Part 11: Salt Spray Test", the salt spray deposition is determined to be (1-3) mL / h·80 cm 2 .

[0125] e) Salt spray test parameters

[0126] Exposure time: 11 days, including 5.5 days for neutral salt spray and 5.5 days for acidic salt spray.

[0127] Salt spray: 5% NaCl solution, pH value is 3.5-4.0, and the salt spray deposition is (1-3) mL / h·80 cm 2 .

[0128] Test temperature: 35℃.

[0129] The protection scope of the present invention is not limited to the above-mentioned embodiments. Obviously, those skilled in the art can make various changes and modifications to the present invention without departing from the scope of the present invention. If these changes and modifications fall within the scope of the claims of the present invention and their equivalents, the present invention is intended to include these changes and modifications.

Claims

1. An experimental design method for life assessment of typical ship structures, characterized in that: The steps include: (1) Determination of the accelerated test spectrum block, which consists of temperature and humidity exposure test, ultraviolet irradiation test and salt spray test; (2) Determination of test parameters. The test parameters of the temperature and humidity exposure test include temperature, humidity, and temperature and humidity exposure time; the test parameters of the ultraviolet irradiation test include temperature, ultraviolet radiation intensity, and ultraviolet irradiation time; the test parameters of the salt spray test include temperature, salt spray exposure time, acid salt spray composition, acid salt spray pH value, acid salt spray exposure time, and salt spray deposition; (3) Carry out the tests in the order of temperature and humidity exposure test, ultraviolet irradiation test and salt spray test and cycle them.

2. The test design method for life assessment of typical ship structures according to claim 1, characterized in that: The method is based on the marine atmospheric environment spectra of the Bohai Sea, the East China Sea and the South China Sea.

3. The test design method for life assessment of typical ship structures according to claim 2, characterized in that: The temperature of the temperature and humidity exposure test refers to the temperature value in the environmental spectrum of the accelerated corrosion test for exposed parts of the aircraft, and the humidity is the humidity value in the environmental spectrum of the accelerated corrosion test for exposed parts of the aircraft.

4. The test design method for life assessment of typical ship structures according to claim 2, characterized in that: The temperature and humidity exposure time is calculated according to the following formula: Where: T is the time that the external structure of the ship is exposed to humid air in one year; T C This is the typical aircraft humid air exposure time.

5. The test design method for life assessment of typical ship structures according to claim 2, characterized in that: The temperature in the UV irradiation test refers to the temperature value in the environmental spectrum of the accelerated corrosion test for exposed aircraft parts, and the UV irradiation intensity refers to the irradiation intensity in the environmental spectrum of the accelerated corrosion test for exposed aircraft parts.

6. The test design method for life assessment of typical ship structures according to claim 2, characterized in that: The ship's ultraviolet radiation time t is calculated according to the following formula: Where: Q Z is the amount of ultraviolet radiation received by the external structure of the ship in one year; W is the radiation intensity of the ultraviolet radiation test chamber.

7. The test design method for life assessment of typical ship structures according to claim 2, characterized in that: The temperature in the salt spray test refers to the salt spray test standard and the temperature value in the environmental spectrum of the accelerated corrosion test for exposed parts of the aircraft; the composition of the acidic salt spray refers to the pH value and ion composition of the water film on the surface of the exposed parts of the aircraft; the pH value of the acidic salt spray refers to the pH value of the acidic salt spray in the three-protection test for exposed parts of the aircraft; the salt spray precipitation amount refers to "GJB 150.11A-2009 Military Equipment Laboratory Environmental Test Method".

8. The test design method for life assessment of typical ship structures according to claim 2, characterized in that: The salt spray action time t of ships is calculated according to the following formula: Where: T' is the total time that the ship's external structure is exposed to salt spray in one year; T Y This is the typical aircraft salt spray exposure time.

9. The test design method for life assessment of typical ship structures according to claim 2, characterized in that: The ratio of the salt spray exposure time to the acid salt spray exposure time is determined based on the ratio of the ship's service time to its berthing time.

10. The test design method for life assessment of typical ship structures according to claim 7, characterized in that: Acidic salt spray uses a 5% NaCl solution added with dilute H2SO4.

Images