运行30～40年后玻璃绝缘子寿命周期的性能测试

The Product Performance Test of the Glass Insulators Used for 30～40 Years

对运行30～40年后的玻璃绝缘子进行了机械破坏负荷、工频击穿电压及残留强度等试验。结果表明,玻璃绝缘子运行后的测试值分别与出厂值基本一致。说明了绝缘子玻璃件在钢化处理(760℃～780℃)时获得了均匀分布的内应力,这种内应力能保持玻璃绝缘子在运行过程中,机电强度不会产生衰减(即不老化)。玻璃绝缘子的自爆主要出现在投运初期,其自爆率呈逐年下降的趋势,最终稳定在一定的水平上。并认为应加大力度开发1000kV交流和±800kV直流特高压线路用玻璃绝缘子。

The tests on mechanical failing load, power frequency puncture voltage and residual strength of glass insulators after 30-40 years service were made. The result shows nearly identical values measured before dispatch from factory and after service, proving a uniform stress distribution obtained at toughen process （760 ℃-780 ℃） which prevent degradation of mechanical strength. Self-shuttering of glass insulators occurs mainly at beginning of service and trends to fall down with service time and afterward is maintained at a certain level. It is considered that greater efforts shall be made for developing glass insulators for 1 000 kV A.C. UHV system and ±800 kV D.C. UHV system.