A first SiC layer formed into a tubular shape and made of a SiC material, a first groove which spirals in one direction along the outer periphery of the first SiC layer, a first SiC fiber layer made of a plurality of SiC fibers wound along the first groove, a second SiC fiber layer made of a plurality of SiC fibers wound outside of the first SiC fiber layer in a direction different from the one direction, and a second SiC layer which is made of a SiC material and which covers the first SiC layer, the first SiC fiber layer, and the second SiC fiber layer are provided. The first SiC fiber layer and the second SiC fiber layer are separated from each other at intersections of the first SiC fiber layer and the second SiC fiber layer.