High-temperature insulating flange suitable for solid oxide electrolysis/power generation system

The utility model discloses a high-temperature insulating flange suitable for a solid oxide electrolysis/power generation system, which comprises an upper flange plate, a lower flange plate, flange extension pipes respectively welded with the upper flange plate and the lower flange plate, and a plurality of fastening bolts for connecting the upper flange plate and the lower flange plate in a penetrating manner, the bolt insulation pads and the bolt protection rings are arranged between the upper side and the lower side of the fastening bolt and the flange plates in pairs, and the high-temperature sealing gaskets are arranged between the upper flange plate and the lower flange plate. An insulating treatment layer is further arranged on the opposite sealing face of the upper flange plate and the lower flange plate, an insulating material is applied to the sealing face through plasma spraying and other technologies to form the bolt protection ring, and the bolt protection ring comprises an annular base body part