Balance correction device for rotor
A single-body balance correction range in which a weight has been removed by single-body balance correction performed on a turbine wheel (a rotor) as a single body is calculated, an assembly balance correction range is calculated in an assembled state of the turbine wheel, and assembly balance correction is performed in a case where the single-body balance correction range and the assembly balance correction range overlap each other, such that an outermost diameter of an arc-shaped assembly-balance correction groove provided by removal of an inner part of a turbine wheel head is smaller than a remaining height a of the single-body balance correction range.
1. A balance correction device comprising:
a controller configured to:
(i) calculate a single-body balance correction range corresponding to a part of an outer peripheral portion of a rotor which has been removed by a single-body balance correction previously performed on the rotor as a single body to form a flat face extending parallel to a center line of rotation of the rotor;
(ii) calculate an assembly balance correction range in an assembled state of the rotor;
(iii) calculate a remaining height on an end surface perpendicular to the center line of rotation of the rotor, the remaining height being a distance between a rotation center position of the rotor and a point of the flat face in the single-body balance correction range, the point being a point at a shortest distance from the rotation center position of the rotor among points on the flat face in the single-body balance correction range;
(iv) perform assembly balance correction such that an inner part of the rotor relative to an outer peripheral edge of the rotor is removed in an arc shape around the rotation center of the rotor; and
(v) perform assembly balance correction in a case where the single-body balance correction range and the assembly balance correction range overlap each other, such that an outermost radius of an arc shaped assembly-balance correction groove provided by the removal of the inner part of the rotor is smaller than the remaining height of the single-body balance correction range.
2. The balance correction device according to claim 1 , wherein
the controller is configured to set the outermost radius of the arc-shaped assembly-balance correction groove such that
in a case where the single-body balance correction range and the assembly balance correction range overlap each other, a difference between the remaining height of the single-body balance correction range and a distance, in a remaining-height direction, between a groove outer peripheral end of the arc-shaped assembly-balance correction groove and the rotation center position of the rotor, is a predetermined value, the groove outer peripheral end being a groove outer peripheral end on a side closer to the single-body balance correction range.