Electric-insulation sealing ring and structure suitable for supercritical conditions

The invention discloses an electric-insulation sealing ring and structure suitable for supercritical conditions. The sealing ring comprises a ring-shaped insulation spacer, wherein the end surfaces of the insulation spacer sink inwards to form steps; the steps are sequentially sleeved by an asbestos rubber plate spacer and a polytetrafluoroethylene spacer from outside to inside; the asbestos rubber plate spacer and the polytetrafluoroethylene spacer are coaxial with the insulation spacer. According to the sealing ring, the steps are formed on the two end surfaces of the insulation spacer in a circle, and the small round surfaces on the inner sides of the steps are sleeved by the asbestos rubber plate spacer and the polytetrafluoroethylene spacer; owing to the combination and matching of different materials, the composite sealing structure is suitable for high-temperature conditions and meets the requirements of a supercritical experiment.