航空液压导管弯曲振动试验方法

FLEXURE VIBRATION TEST METHOD OF AVIATION TUBE

1.引言 在飞行器研制中,液压管路系统的疲劳寿命是一个重大问题,各国对此都十分重视,因而进行了大量的试验研究,国际标准化组织(ISO)也做了很多工作。 我国尚未开展旋转弯曲试验,缺乏这方面的实践经验,但在悬臂梁和简支梁方面做了不少工作,遇到过不少问题。首先是如何确定试件长度。N836和N925给出的方法是:先安装“足够”长的导管,然后“不断调整”,直到满足要求的谐振频率为止。这显然是行不通的。美国军用标准及规范MIL-F-182801)

For aviation vehicles the reliability of hydraulic tube system is so important that any damage of the tube may causes catastrophe in flight. Flexure vibration test of hydraulic tubes is necessary to ensure the reliability and to reduce the weight. Comparing with the several test methods in International Organiztion For Standardization (ISO) and Military Specification of U.S. A, the paper discusses and complements the cantilever beam method and the simple beam method for flexure vibration tests of aviation tubes. The contents in the paper include estimating the length of the test specimen) transforming static strain to stress due to oil pressure, the method of strain control or stress control, the error due to diametral size of specimen and the effects due to size and positions of strain gages.