Method of manufacturing impeller of centrifugal rotary machine and impeller of centrifugal rotary machine

摘要

A method of manufacturing an impeller (1) of a centrifugal rotary machine, the impeller being formed in a substantially disk shape and including a passageway (2) curved to follow the axial direction in an inner peripheral side of the impeller and to follow the radial direction as it goes to an outer peripheral side thereof, the method includes: a first passageway forming step of setting a rotation center at a position on one side of the axial direction where a curvature center of the passageway is located relative to a disk forming an eternal shape of the impeller, and rotating a processing tool about the rotation center relative to the disk so as to form at least a part of the passageway from a position which is an inner peripheral end of the passageway of the disk toward the outer peripheral side.