Experimental Methods of Determination of Short- and Long-term Mechanical Strength of Ceramic Insulators
Abstract
The subject of this paper are the properties of ceramic insulators responsible for transmission of mechanical stresses due to their construction and destination. Taking into account the information about failure of the insulators, the effect of electrical stresses imposed on the insulator structure by the electric field can be neglected. In view of this fact, our considerations concern the parameters characterising short and long-term mechanical strengths and the method of forecasting the minimal time to the mechanical failure.References
1. J. RANACHOWSKI, F. REJMUND and J. BERTRAND, Quality and reliability of insulators applied to electrical power [in Polish], Mat. of Conf. "Outdoor high voltage insulation for electrical power engineering", Scientific Papers of the Institute of Found. El. Engng. of the Technological University of Wroclaw, 32, 9, pp. 19–41, 1997.
2. J. RANACHOWSKI and P. RANACHOWSKI, Method of the "lifetime" determination of ceramic insulator material [in Polish], Protocol for Polish Electroenergetic Networks S.A., Warsaw 1997.
3. J. RANACHOWSKI, F. REJMUND and P. RANACHOWSKI, Determination of critical stress intensity factor and evaluation of lifetime of line long-rod insulator type LP–75/31 W [in Polish], Expert opinion IPPT PAN, No. NWN/193/BU/95, Warsaw 1996.
4. K. NÜHARA, R. MORENA and D.P.H. HASSELMAN, Evaluation of $K_{IC}$ of brittle solids by the indentation method with low crack-to-indent ratios, J. Mater. Sci. Letters, 1, pp. 13–16, 1982.
5. J. RAABE and E. BOBRYK, Determination of Weibull factor $m$ and stress intensity coefficient $K_{IC}$ of ceramics for electronics [in Polish], Electronic Materials, 3, 75, 1991.
2. J. RANACHOWSKI and P. RANACHOWSKI, Method of the "lifetime" determination of ceramic insulator material [in Polish], Protocol for Polish Electroenergetic Networks S.A., Warsaw 1997.
3. J. RANACHOWSKI, F. REJMUND and P. RANACHOWSKI, Determination of critical stress intensity factor and evaluation of lifetime of line long-rod insulator type LP–75/31 W [in Polish], Expert opinion IPPT PAN, No. NWN/193/BU/95, Warsaw 1996.
4. K. NÜHARA, R. MORENA and D.P.H. HASSELMAN, Evaluation of $K_{IC}$ of brittle solids by the indentation method with low crack-to-indent ratios, J. Mater. Sci. Letters, 1, pp. 13–16, 1982.
5. J. RAABE and E. BOBRYK, Determination of Weibull factor $m$ and stress intensity coefficient $K_{IC}$ of ceramics for electronics [in Polish], Electronic Materials, 3, 75, 1991.
