摘要
超声检测的结果依赖于试块与实际检测对象的吻合程度。为了提高运行中支柱瓷绝缘子检测的有效性和可靠性,结合支柱瓷绝缘子的瓷柱表面特征、以及产生的缺陷状况,设计制作了含有不同缺陷的系列模拟试块,并用研制的不同频率、不同折射角的小角度纵波探头和爬波探头对其进行测试研究。试验结果表明,小角度纵波探头对瓷柱内部缺陷有很好的检测灵敏度,而检测表面小裂纹时会受到瓷柱表面瓷砂的严重干扰;爬波探头不受瓷砂的影响,能灵敏地检测瓷柱表面裂纹。所以,单独使用小角度纵波方法或爬波方法,均不能完全检测出绝缘子瓷体内部与表面的小缺陷;应将两种方法结合使用,才能保证实际检测的有效性。
The results of ultrasonic testing depend on consistent degree of calibration between blocks and the tested objects. According to surface characteristics and defects status of porcelain post insulators, a series of similar porcelain calibration blocks with different defects were designed, while the probes were made with different frequencies and refractive angles. Then the blocks were tested by small angle longitudinal wave and creeping wave, in order to heighten reliability and validity of testing post porcelain insulators in service. The probes were made with different frequencies and refractive angles. Experimental results show that small angle longitudinal wave can detect internal defects sensitively, but it is interfered by porcelain sands seriously when detecting small surface defects. Creeping wave can detect surface defects sensitively ignoring effects of porcelain sands. Hence, small internal and surface defects of porcelain insulators can not be detected completely by single small angle longitudinal wave or creeping wave. Testing technique combining two methods is put forward to insure testing validity.
出处
《中国电机工程学报》
EI
CSCD
北大核心
2006年第9期159-163,共5页
Proceedings of the CSEE
关键词
瓷绝缘子
超声波
有效性
porcelain insulator
ultrasonic
validity