电工技术学报2025,Vol.40Issue(5):1614-1627,14.DOI:10.19595/j.cnki.1000-6753.tces.240299
内水压试验对大吨位圆柱头瓷绝缘子杂质缺陷剔除有效性研究
Analysis of Removing Impurity Defects in Hydraulic Test of Cylindrical Head Suspended Porcelain Insulator
摘要
Abstract
Porcelain parts of insulator are generally made of calcined alumina and inorganic minerals such as clay and feldspar in accordance with the ratio of firing.Due to impurities in raw materials and kilns in the production process,there may be defects such as impurities and pores in porcelain parts.In the actual operating environment,the insulator is subjected to electrical,thermal and mechanical stress,as a result of which internal defects of porcelain parts may be further expanded,resulting in a significant decline in the overall mechanical and electrical properties of the insulator.In order to improve the overall quality of insulators,DL/T 1001.1 stipulates that porcelain parts need to carry out hydraulic test one by one before adhesive assembly to remove the defects in porcelain parts,but the standard doesn't clearly specify the key test parameter(water pressure),manufacturing enterprises set the pressure based on experience,the test parameters lack scientific basis.In order to scientifically guide the setting of the test conditions of the internal hydraulic test,the types and distribution positions of the removal defects by internal hydraulic test were statistically analyzed,and different factors affecting the sensitivity of the removal of impurities in the internal hydraulic test were analyzed. First of all,the hydraulic test of domestic porcelain insulator manufacturers was investigated,and it was found that the manufacturers didn't carry out detail statistics of the position and type of defects removed by the hydraulic test.The author went to a domestic insulator manufacturer to track a batch of products,collect the porcelain pieces destroyed in the hydraulic test,and classify the defects on the section,which are mainly divided into yellow core,micro-cracks,impurities and so on. Secondly,the article has analyzed the internal stress distribution of intact porcelain parts in the hydraulic test by finite element simulation.On this basis,according to different types of defects,the stress calculation is carried out by setting up defect model.The stress distribution in the hydraulic test is taken as the boundary stress condition of the calculation of submodel,and different defects are set in the submodel to calculate the local stress.The sensitivity of internal hydraulic test to remove different defects is analyzed by calculating the stress concentration coefficient at the defect.According to the results,the influence of elastic modulus,size and shape of impurities and different stress boundary conditions on the stress concentration coefficient at the defect is analyzed. Finally,the article analyzed the reasonableness of the current hydraulic test conditions in the manufacturers based on the first principal theory.The subsequent work will further optimize the setting of internal water pressure test conditions based on the statistical accumulation of defect removal data from the manufacturer's internal water pressure test and the actual operation of the large-tonnage porcelain insulators produced by the manufacturer in the line.关键词
圆柱头绝缘子/内水压试验/有限元仿真/夹杂应力Key words
Cylindrical head insulator/hydraulic inner pressure test/finite element simulation/stress of inclusions分类
信息技术与安全科学引用本文复制引用
仪明哲,文路,梅红伟,曹彬,王黎明..内水压试验对大吨位圆柱头瓷绝缘子杂质缺陷剔除有效性研究[J].电工技术学报,2025,40(5):1614-1627,14.基金项目
国家自然科学基金资助项目(51977117). (51977117)