Radiation resistant cable

Ukon, Seiichi*; Ishida, Katsuyoshi*; Takano, Kazuhiko*; Furukori, Hisayoshi*; Kusano, Joichi*

In general, polymeric cable installed in heavy radiation environment, such as nuclear power plant or radiation research facility as the J-PARC, deteriorates its performance by the effect of radiation damage. The deterioration conducts a decreasing of mechanical property and of flame retardant characteristics that require the replacement of the cable within a certain period of time to keep the basic function as insulation or non-flammability. This report explains the development of radiation resistant polymeric material and cable by the examination of sample -ray irradiation method based on the joint research agreement with JAEA toward the J-PARC application. We studied the irradiation effect in the combination of light stabilizer and ultraviolet absorber. A current non-halogen sheath material was observed severe damage on the mechanical property by the irradiation dose of 0.5 MGy. While the developed material demonstrated excellent performance as the elongation brake at 50%, which corresponding to the self-diameter bending, kept after the irradiation dose of 2.5 MGy. The new cable manufactured with the advanced sheath material maintained at the vertical tray flame test of JIS C 3521, and accomplished to a bending test, in case of the cable was bent to a diameter 4 times of the cable outer diameter, as well as all of the development objectives were achieved successfully after the irradiation dose of 2.5 MGy.