热老化下油中绝缘纸纤维颗粒脱落规律研究

Abscission Law of Fiber Particles of Insulating Paper Under Thermal Aging

为探索热老化下绝缘纸纤维颗粒脱落规律,通过偏光显微镜捕获油中纤维颗粒的微观特性参数,从绝缘纸表面纤维形态及纤维断裂特征、纤维长度与数量的分布规律和纤维脱落的影响因素三方面进行探索。结果表明:随着老化时间的增加,绝缘纸表面纤维裂缝并出现孔洞;油中长纤维数量减少,短纤维数量增多;纤维数量与绝缘纸纤维素链的平均断键数满足线性关系;随着温度与绝缘纸初始水分含量的增加,油中短纤维比例升高,长纤维比例降低,纤维数量增多。

In order to explore the abscission law of fiber particles in oil under thermal aging,the microscopic characteristic parameters of fiber particles in oil were captured by polarized light microscopy in this paper.The fiber morphology and fiber fracture characteristics,the distribution of fiber length and quantity,and the influencing factors of fiber shedding were investigated.The results show that,with the increase of aging time,the cracks and pores on the surface of the insulating paper increase;The number of long fibers decreases and that of short fibers increases;the number of fibers in the oil and the average number of broken bonds of cellulose chain satisfy a linear relationship;As the temperature and the initial moisture content of the insulating paper increase,the proportion of short fibers in the oil increases,the proportion of long fibers decreases,and the number of fibers increases.