抄録
Rubber insulating gloves for electrical working must always keep dielectric properties in good condition in order to prevent a line man from electric shock. However, they are deteriorated by various stresses to which they are subjected in service and keeping. Therefore, their dielectric deterioration and estimation of lifetime were studied when they were actually used in high voltage electrical working on pole of distribution lines, because such a place is considered where the frequency of use is large and the environment is severe. As the result, it was found that the usable lifetime was considerably shorter than expected because of their mechanical damages in service. Also, measured dielectric and mechanical properties showed deterioration tendencies on the whole, though their data scattered on a wide range. And the voltage endurance lifetime was estimated for the used days with the help of statistical treatment, and it was confirmed that there are cases where a few used gloves fail in the voltage proof test of 10kV even if they once passed in the withstand test of 20kV when they were new products. Furthermore, it was also shown that the electrical breakdown point was not decided by innumerable slight scratches caused in service.
