Butterfly valve

A butterfly valve comprising a valve body having at least a surface formed of resin material and being formed therein with an internal flow passage, a valve stem rotatably supported by the valve body, a valve element connected to the valve stem to be rotatably supported by the valve body and placed in the internal flow passage, and bushings externally fitted around the valve stem,

• wherein the valve body is provided with bearing holes each rotatably supporting the valve stem via the corresponding bushing and the bearing holes each extends to an opening adjacent to the internal flow passage;
• each bearing hole and the corresponding bushing have shapes such that a gap is formed between an inner peripheral surface of the bearing hole and an outer peripheral surface of the corresponding bushing in a region adjacent to the opening;
• and
• there is an annular neck portion provided on an outer periphery of a portion of each bushing located adjacent to the opening, and the gap between inner peripheral surface of each bearing hole and the outer peripheral surface of the corresponding bushing is formed by the neck portion.