Testing method for combined stress of airplane brake system

Abstract

The invention provides a testing method for combined stress of an airplane brake system. The combined stress test section is incorporated into an extreme value environment condition in use to stimulate a using failure. According to the testing method for the combined stress of the airplane brake system, the overlaying effect is generated by simultaneously applying temperature and temperature changes, power supply voltage fluctuation, hydraulic stress and vibratory stress which exist simultaneously during using of the brake system, wherein the power supply voltage fluctuation is the power supply character, so that the failure stimulating effect is enhanced. A test for the brake system is completed under the combined stress condition within 90,000 min / 1,500 h, seven verifications such as the service life indicator for 2000 times of taking off and landing of the braking system, average failure interval time with 2000h of MTBF, high temperature, low temperature, vibrating, temperature impact and the power supply character are completed in one test, and the problem that the service life and reliability indicator of the brake system in the prior art cannot be comprehensively verified is solved. According to the combined stress testing method for the airplane brake system, testing cost is reduced, failures during using of civil airplane products are reduced, the flight attendance rate is improved, and reliability of a civil airplane is improved.

Description

technical field [0001] The invention relates to the field of civil aircraft product development, in particular to a method for determining the type of comprehensive test stress of a civil aircraft brake system and the proportion of each stress in a test section, and then determining the test section. Background technique [0002] The tests in the development process of existing civil aircraft products are divided into the following categories: [0003] 1) Environmental test, used to verify the environmental adaptability of the product. [0004] 2) The power supply characteristic test is used to verify the ability of the product to work normally under the condition of power supply voltage fluctuation. [0005] 3) Reliability test, used to verify whether the product meets the specified reliability index. [0006] 4) Durability test, also called life test, is used to verify the life index of the product. [0007] The above four tests are carried out in accordance with the co...

AI Technical Summary

Problems solved by technology

[0023] 1) The reliability test is carried out under real time-sequence comprehensive environmental conditions, lack of working stress, and real test results cannot be obtained under no-load conditions. For example: the analog circuit anti-skid brake control box in the braking system is powered on at 4mA, and the working state is 40mA, 10 times difference

There are such facts at home and abroad, after the test is passed, there are many failures in use. The reason is that no working stress is applied during the test process, and the test results are not true.

[0024] 2) The life test is based on the combined stress test of a single product at normal temperature. The working stress is applied but the test section has limitations. The landing brake pressure of 10MPa is the main force, and the performance at room temperature cannot indicate that the performance under various comprehensive environmental conditions such as high temperature, low temperature, vibration and impact is qualified.

[0025] 3) Part of the items in the life, reliability and environmental tests are repeated, wasting time and resources

[0026] 4) Xi'an Aviation Brake Technology Co., Ltd. proposed an accelerated life test method for aircraft brake systems in patent 201110443125.8. In this method, a combination of life and reliability tests is proposed, but this method applies combined stress instead of environmental stress at the same time. And working stress, there are also cases where the test does not match the use situation;

[0027] 5) In the inventions and creations with application numbers 201710490975.0, 201710490987.3 and 201710490970.8, the problems of low-temperature life, high-temperature life and vibration life of the brake system were respectively solved, and it is suitable for independent verification of low-temperature, high-temperature and vibration weak links of the brake system , did not verify the life and reliability under the combined effects of low temperature, high temperature, temperature change and vibration in the air, there is a single verification and limitations

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