Method for attaching/removing vane ring and auxiliary support device for vane segment used in said method

1. A method for attaching a vane ring in a rotary machine, the rotary machine being provided with:

a rotor configured to rotate about an axis,

a casing covering the rotor and being configured to allow the rotor to rotate, and

a vane ring formed in an annular shape about the axis and provided on an inner circumferential side of the casing,

the vane ring being able to split into a plurality of vane segments in a circumferential direction about the axis, the casing being able to split into a plurality of partial casings in the circumferential direction, and vane ring grooves being respectively formed in the partial casings, the vane ring grooves being depressed from an inside in a radial direction toward an outside in the radial direction with respect to the axis and extending in the circumferential direction, and

the plurality of vane segments being mounted in the vane ring grooves of any of the plurality of partial casings,

the method comprising:

a casing disposing step of disposing a target casing, which is any one of the plurality of partial casings and is split away from another of the plurality of partial casings at a split surface, with the split surface of the target casing facing downward, at a workable position where a space is secured such that it is possible to dispose a target segment below the target casing, target segment being one of the vane segments to be attached to the target casing; and

a segment moving step of moving the target segment, which comprises a plurality of vanes and forms an arc shape, in the circumferential direction with respect to the target casing disposed at the workable position from a state in which a center side of the arc shape of the target segment is facing upward, and mounting the target segment in the vane ring groove of the target casing.

2. The method for attaching a vane ring according to claim 1 , wherein the partial casings are a top casing forming an upper side of the casing and a bottom casing forming a lower side of the casing, and the target casing is the top casing.

3. The method for attaching a vane ring according to claim 2 , wherein, in the casing disposing step, the top casing is moved, while maintaining a state where the split surface of the top casing faces downward, between a casing-facing position where the top casing is disposed on the bottom casing and the workable position.

4. The method for attaching a vane ring according to claim 1 , wherein, in the casing disposing step, by placing the target casing on a casing support base supporting the target casing from below, the target casing is disposed at the workable position and a state where the target casing is disposed at the workable position is maintained.

5. The method for attaching a vane ring according to claim 1 , wherein, in the segment moving step, the target segment disposed or to be disposed in the space below the target casing is received using an auxiliary support device for receiving the target segment.

6. A method for attaching/removing a vane ring in a rotary machine, the rotary machine being provided with:

a rotor configured to rotate about an axis,

a casing covering the rotor and being configured to allow the rotor to rotate, and

a vane ring formed in an annular shape about the axis and provided on an inner circumferential side of the casing,

the vane ring being able to split into a plurality of vane segments in a circumferential direction about the axis, the casing being able to split into a plurality of partial casings in the circumferential direction, and vane ring grooves being respectively formed in the partial casings, the vane ring grooves being depressed from an inside in a radial direction toward an outside in the radial direction with respect to the axis and extending in the circumferential direction, and

the plurality of vane segments being mounted in the vane ring grooves of any of the plurality of partial casings,

the method comprising:

a casing disposing step of disposing a target casing, which is any one of the plurality of partial casings and is split away from another of the plurality of partial casings at a split surface, with the split surface of the target casing facing downward, at a workable position where a space is secured such that it is possible to dispose a target segment below the target casing, the target segment being one of the vane segments attached or to be attached to the target casing; and

a segment moving step of moving the target segment, which comprises a plurality of vanes and forms an arc shape, in the circumferential direction with respect to the target casing disposed at the workable position from a state in which a center side of the arc shape of the target segment is facing upward, and disposing the target segment in the space below the target casing or mounting the target segment in the vane ring groove of the target casing,

wherein, in the segment moving step, the target segment disposed or to be disposed in the space below the target casing is received using an auxiliary support device for receiving the target segment,

wherein the auxiliary support device has a guide rail which is opposed to an outer circumferential surface of the target segment and formed in an arc shape with a curvature corresponding to a curvature of the outer circumferential surface of the target segment and supports the target segment, and

wherein, in the segment moving step, the auxiliary support device is disposed such that the vane ring groove of the target casing where the target segment is mounted or is to be mounted is on an extension of the arc of the guide rail of the auxiliary support device, and the target segment is moved along the vane ring groove of the target casing and the guide rail.