Method for calculating the gap change between airfoil rings and method for adjusting the position of airfoil rings
Patent Information
- Authority / Receiving Office
- JP · JP
- Patent Type
- Patents
- Current Assignee / Owner
- MITSUBISHI HEAVY IND LTD
- Filing Date
- 2024-01-09
- Publication Date
- 2026-07-31
AI Technical Summary
【0009】 本開示の翼環の間隙変化量算出方法および翼環の位置調整方法によれば、ケーシング組立作業の作業性の向上を図ることができる。
Smart Images
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Abstract
Description
Technical Field
[0001] The present disclosure relates to a method for calculating the amount of change in the gap between wing rings and a method for adjusting the position of wing rings.
Background Art
[0002] A steam turbine as a rotating machine includes a casing, a rotor, stationary blades, and moving blades. The casing has a rotor rotatably supported therein, and a plurality of moving blades are fixed to the rotor at intervals in the axial direction. Further, the casing has a plurality of stationary blades fixed therein at intervals in the axial direction. The stationary blades and the moving blades are alternately arranged in the axial direction. The casing is A wing ring is fixed to the inner peripheral portion. The wing ring is configured by providing a plurality of stationary blades at intervals in the circumferential direction between an outer ring and an inner ring, and has a ring shape. The wing ring is split into two parts vertically and forms a ring shape by being fastened with bolts.
[0003] Casing The disassembly of is external Casing upper half, inside Casing upper half, upper half of the wing ring are removed in this order, and finally the rotor is removed. And Casing The assembly of is the reverse procedure of the disassembly. Casing At the time of assembling, it is necessary to adjust the gap between the outer peripheral surface of the rotor and the inner peripheral surface of the wing ring to an appropriate value. In particular, the wing ring may gradually increase in strain over time and undergo creep deformation. Therefore, is temporarily assembled in advance, and the gap between the outer peripheral surface of the rotor and the inner peripheral surface of the wing ring is measured using a measuring instrument. As such a technique, for example, there is one in Patent Document 1 Casing and so on. The
Prior Art Documents
Patent Documents
[0004]
Patent Document 1
Summary of the Invention
Problems to be Solved by the Invention
[0005] The technology described in Patent Document 1 involves measuring the gap between the outer surface of the rotor and the inner surface of the blade ring using a measuring instrument. In this case, Casing This requires temporary assembly of the wing rings, which takes a long time, resulting in poor work efficiency.
[0006] This disclosure addresses the aforementioned issues, Casing The objective is to provide a method for calculating the amount of gap change between airfoil rings and a method for adjusting the position of airfoil rings, thereby improving the workability of assembly work. [Means for solving the problem]
[0007] A method for calculating the gap change amount of a blade ring according to the present disclosure for achieving the above objective, wherein a blade ring is configured to form a ring shape by connecting an upper half of a blade ring and a lower half of a blade ring, and the method for calculating the vertical gap change amount between the inner circumferential surface of the blade ring and the outer circumferential surface of a rotation axis disposed inside the blade ring comprises the steps of: obtaining the amount of horizontal displacement of the blade ring in a first state in which the upper half of the blade ring is connected to the lower half of the blade ring and in a second state in which the upper half of the blade ring is removed from the lower half of the blade ring; calculating the second neutral axis of the blade ring in the second state based on the amount of displacement; and calculating the gap change amount between the first state and the second state by comparing the first neutral axis of the blade ring in the first state and the second neutral axis.
[0008] Furthermore, the method for adjusting the position of the airfoil ring according to this disclosure adjusts the vertical position of the airfoil ring based on the amount of gap change calculated by the method for calculating the amount of gap change of the airfoil ring when assembling the upper half of the airfoil ring to the lower half of the airfoil ring. [Effects of the Invention]
[0009] According to the method for calculating the gap change amount of the blade ring and the method for adjusting the position of the blade ring in this disclosure, Casing This can improve the efficiency of assembly work. [Brief explanation of the drawing]
[0010] [Figure 1] Figure 1 is a schematic diagram showing the internal structure of a steam turbine. [Figure 2] Figure 2 is a schematic diagram showing the inside of the steam turbine casing. [Figure 3] Figure 3 is an explanatory diagram illustrating the change in the gap in response to the creep deformation of the airfoil ring. [Figure 4] Figure 4 is a flowchart illustrating the method for calculating the gap change in the blade ring of the first embodiment. [Figure 5] Figure 5 is an explanatory diagram illustrating the method for calculating the change in the gap between the airfoil rings. [Figure 6] Figure 6 is a flowchart illustrating the method for adjusting the position of the airfoil ring. [Figure 7] Figure 7 is an explanatory diagram illustrating the method for calculating the gap change amount of the blade ring in the second embodiment. [Figure 8] Figure 8 is an enlarged view illustrating the method for calculating the change in the gap between the airfoil rings. [Figure 9] Figure 9 is a flowchart illustrating the method for calculating the gap change in the blade ring in the second embodiment. [Modes for carrying out the invention]
[0011] Preferred embodiments of the present disclosure will be described in detail below with reference to the drawings. However, these embodiments do not limit the present disclosure, and where there are multiple embodiments, they may be combinations of these embodiments. Furthermore, the components in the embodiments include those readily conceivable by those skilled in the art, those that are substantially identical, and those that are equivalent.
[0012] [First Embodiment] <Steam Turbine> In the first embodiment, the method for calculating the gap change between blade rings and the method for adjusting the position of the blade rings will be explained by applying them to a steam turbine as a rotating machine. However, the rotating machine is not limited to a steam turbine. Figure 1 is a schematic diagram showing the internal structure of a steam turbine.
[0013] In the first embodiment, a steam turbine will be described as an example of a rotary machine. However, the rotary machine is not limited to a steam turbine, and any configuration in which a rotating body is rotatably supported with respect to a stationary body may be used.
[0014] As shown in FIG. 1, a steam turbine (rotary machine) 10 includes a casing (stationary body) 11, a rotor (rotating shaft) 12, stator blades 13, and rotor blades 14.
[0015] The casing 11 has a hollow shape, and the rotor 12 is arranged inside it along the horizontal direction. The rotor 12 is rotatably supported about the axis O1 by bearings 21 and 22 provided on the casing 11 (or the foundation of the plant). The stator blades 13 are fixedly arranged at a plurality of positions on the inner peripheral portion of the casing 11 at intervals in the axial direction A of the rotor 12. The rotor blades 14 are fixedly arranged at a plurality of positions on the outer peripheral portion of the rotor 12 at intervals in the axial direction A. The stator blades 13 are arranged along the radial direction R of the rotor 12 and at intervals in the circumferential direction of the rotor 12. The rotor blades 14 are arranged along the radial direction R of the rotor 12 and at intervals in the circumferential direction of the rotor 12, and the stator blades 13 and the rotor blades 14 are arranged alternately in the axial direction A.
[0016] The casing 11 is provided with a steam supply port 23 at one end in the axial direction A. The steam supply port 23 communicates with a blade row portion 25 where the stator blades 13 and the rotor blades 14 are arranged through a steam passage 24. The blade row portion 25 communicates with an exhaust chamber 26. The casing 11 is provided with a steam discharge port 27 at the other end in the axial direction A. The steam discharge port 27 communicates with the exhaust chamber 26.
[0017] High-pressure steam is supplied from the steam supply port 23 through the steam passage 24 to the blade row portion 25. As the steam passes through the plurality of stator blades 13 and the plurality of rotor blades 14, the rotor 12 is driven to rotate via each rotor blade 14. The rotor 12 is connected to a generator (not shown), and the generator is driven by the driving force of the rotor 12. The steam that has driven each rotor blade 14 is discharged to the outside from the steam discharge port 27 through the exhaust chamber 26.
[0018] <Wing ring> Figure 2 shows the steam turbine Casing This is a schematic diagram showing the internal structure.
[0019] As shown in Figure 2, the casing 11 is constructed Casing Number 31 is a type that is split into two parts, top and bottom. Casing Upper half 32 and Casing The lower half 33 and the ring 34 are connected by bolts (not shown) to form a ring shape. The wing ring 34 has an outer ring 35, an inner ring 36, and a plurality of stationary vanes 13. The plurality of stationary vanes 13 are arranged circumferentially at intervals between the outer ring 35 and the inner ring 36. The wing ring 34 is, Casing Similar to 31, it is split into two parts vertically, and the upper half of the wing ring 37 and the lower half of the wing ring 38 are connected by bolts (not shown) to form a ring shape. The wing ring 34 is Casing It is positioned inside 31 and supported by support parts 39 and 40.
[0020] <Creep deformation of wing rings> Figure 3 is an explanatory diagram illustrating the change in the gap in response to the creep deformation of the airfoil ring.
[0021] As shown in Figure 3, creep deformation occurs in the blade ring 34 during the operation of the steam turbine. Therefore, Casing When part 31 is disassembled, and then the airfoil ring 34 is disassembled, creep deformation occurs in the upper part 37 and lower part 38 of the airfoil ring as the constraints imposed by the bolts are released. Specifically, the upper part 37 and lower part 38 of the airfoil ring curve slightly inward, and the mounting surfaces 37a, 37b and 38a, 38b are no longer parallel.
[0022] When the blade ring 34 is assembled, the creep deformation is corrected when the upper half 37 and lower half 38 of the blade ring are connected by bolts. That is, the upper half 37 and lower half 38 of the blade ring are slightly curved outward, and the mounting surfaces 37a, 37b and mounting surfaces 38a, 38b become parallel. However, because the lower half 38 of the blade ring rises slightly relative to the rotor 12, the vertical gap S at the bottom of the outer surface of the rotor 12 and the inner surface of the blade ring 34 decreases and becomes narrower.
[0023] <Method for calculating the change in gap between wings> Figure 4 is a flowchart showing the method for calculating the gap change amount of the blade ring in the first embodiment, and Figure 5 is an explanatory diagram for explaining the method for calculating the gap change amount of the blade ring.
[0024] As shown in Figure 3, the first embodiment's method for calculating the gap change in the blade ring is configured such that the upper half 37 and the lower half 38 of the blade ring are connected to form a ring shape, and the amount of change in the vertical gap between the inner circumferential surface of the blade ring 34 and the outer circumferential surface of the rotor (rotating shaft) 12 located inside the blade ring 34 is calculated.
[0025] The calculation of the gap change between the airfoil rings is handled by the control unit. The control unit is a controller, and is implemented by various programs stored in memory, such as a CPU (Central Processing Unit) or MPU (Micro Processing Unit), executing them using RAM as the working area. The control unit is also connected to an operating device such as a keyboard, and the operator inputs various command signals to the control unit using the operating device, thereby performing the calculation of the gap change between the airfoil rings.
[0026] Here, the method for calculating the gap change amount of the blade ring in the first embodiment is to predict and calculate the gap change amount from the back surface measurement value when the blade ring 34 is disassembled by geometric calculation based on the following assumptions. 1. Back measurement These are horizontal measurements taken near the mounting surfaces 37a, 37b, 38a, and 38b. Therefore, the change in the back surface measurement corresponds to the change in the radius of curvature. 2. Before assembly of the wing ring 34, the mounting surfaces 38a and 38b were inclined, but after assembly, they become horizontal mounting surfaces 37a and 37b. As a result, a uniform bending moment acts on the upper half 37 or lower half 38 of the wing ring, causing deformation that changes the radius of curvature rather than elliptical deformation. Therefore, the neutral axis of the upper half 37 and lower half 38 of the wing ring 34 after assembly remains a perfect circle. 3. The arc length of the first neutral axis after assembly of the wing ring 34 is the same as the arc length of the second neutral axis before assembly.
[0027] In Figure 4, steps S11 to S15 are processes performed on the wing ring 34 when it is in a first state, with the upper wing ring portion 37 connected to the lower wing ring portion 38. Steps S16 to S20 are processes performed on the wing ring 34 when it is in a second state, with the upper wing ring portion 37 removed from the lower wing ring portion 38.
[0028] As shown in Figure 4, in step S11, the cross-sectional shape of the airfoil ring 34 is obtained. The cross-sectional shape of the airfoil ring 34 in the first state is obtained from the design value of the airfoil ring 34 or the measured value of the airfoil ring 34 in the first state. In step S12, the first neutral axis of the airfoil ring 34 in the first state is calculated. Then, in step S13, the first radius of curvature is calculated based on the first neutral axis VA1.
[0029] That is, as shown in Figure 5, the lower half of the blade ring 34 is supported by two support parts 39 and 40. Here, the first neutral axis VA1 is defined as the moment when a bending moment is generated with respect to the blade ring 34 in the first state. Stress This is the position of the cross-section where it does not occur. In this case, the support parts 39 and 40 are assumed to have support points 39a and 40a on the first neutral axis VA1, and support the first neutral axis VA1 of the airfoil ring 34 in the first state. Here, the support points 39a and 40a of the support parts 39 and 40 with respect to the first neutral axis VA1 are set. Then, the first radius of curvature R1 at the first neutral axis VA1 is calculated.
[0030] Returning to Figure 4, in step S14 the first neutral axis VA1 is drawn, and in step S15 the first measurement point is drawn. That is, as shown in Figure 5, the support parts 39, 40 Supporting celestial bodies 39a and 40a A first neutral axis VA1 passing through is drawn. Here, the support points 39a and 40a of the support parts 39 and 40 become the first measurement points.
[0031] Returning to Figure 4, in step S16, the back surface measurement value of the wing ring 34 in the second state is obtained. That is, as shown in Figure 3, the back surface measurement value H2 is when the wing ring 34 is in the second state. Casing 31( Casing upper half 32, Casing This is the horizontal length between the inner wall surface of the lower half 33) and the support point 39b (40b). In this case, the back surface measurement value is obtained by taking the back surface measurement values on both sides of the wing ring 34 and averaging the back surface measurement values on both sides. The back surface measurement value H1, which will be described later, is when the wing ring 34 is in the first state. Casing 31( Casing upper half 32, Casing This is the horizontal length between the inner wall surface of the lower half 33) and the support point 39a (40a), and is either a design value or a measured value.
[0032] Returning to Figure 4, in step S17, the change in the back surface measurement value is calculated. That is, the horizontal displacement between the airfoil ring 34 in the first state and the airfoil ring 34 in the second state is obtained as the change in the back surface measurement value. In other words, the deviation between the back surface measurement value H1 of the airfoil ring 34 in the first state and the back surface measurement value H2 of the airfoil ring 34 in the second state is calculated as the change in the back surface measurement value ΔH. In this case, in step S18, the second measurement point is drawn. In step S19, the second radius of curvature is calculated. In step S20, the second neutral axis is drawn.
[0033] Specifically, as shown in Figure 5, for the first neutral axis VA1 and the first measurement points, support points 39a and 40a, of the airfoil ring in the first state drawn in steps S14 and S15, the second measurement points, support points 39b and 40b, are drawn based on the change amount ΔH of the back surface measurement value. Then, the second radius of curvature R2 is calculated such that the arc lengths of support points 39a and 40a on the first neutral axis VA1 match the arc lengths of support points 39b and 40b, and the second neutral axis VA2 is drawn.
[0034] Then, returning to Figure 4, in step S21, Change in gap This is calculated as follows: As shown in Figure 5, the change in the back surface measurement value ΔH, which is the amount of horizontal displacement with respect to the wing ring 34, is output as the gap change ΔS.
[0035] <Method for adjusting the position of the wing rings> Figure 6 is a flowchart illustrating the method for adjusting the position of the airfoil ring.
[0036] As shown in Figures 2 and 6, in step S31, Casing The upper half 32 is removed. In step S32, the back surface measurement value H1 of the airfoil ring 34 is measured. In step S33, the upper half 37 of the airfoil ring is removed. In step S34, the back surface measurement value H2 of the airfoil ring 34 is measured. Then, in step S35, the gap change amount ΔS due to the change in radius of curvature is obtained by the above-described process (steps S11 to S21). Then, when assembling the upper half 37 of the airfoil ring, in step S36, the vertical position adjustment of the airfoil ring 34 is performed using the gap change amount ΔS.
[0037] [Second Embodiment] Figure 7 is an explanatory diagram illustrating the method for calculating the gap change amount of the blade ring in the second embodiment, and Figure 8 is an enlarged view illustrating the method for calculating the gap change amount of the blade ring.
[0038] As shown in Figure 7, in the first embodiment, the support parts 39 and 40 were described as having support points 39a and 40a on the first neutral axis VA1, supporting the first neutral axis VA1 of the airfoil ring 34 in the first state. However, in this case, if the support points 39a and 40a (39b and 40b) of the airfoil ring 34 are away from the neutral axis, it is necessary to consider the vertical displacement of the airfoil ring 34 during assembly.
[0039] In the second state, when the support point 40b is on the outer surface of the lower half of the airfoil ring 38, the distance L from the support point 40b to point VA2a, which is the shortest distance from the support point 40b to the second neutral axis VA2, is set. Similarly, in the first state, when the support point 40a is on the outer surface of the lower half of the airfoil ring 38, the distance L from the support point 40a to point VA1a, which is the shortest distance from the support point 40a to the first neutral axis VA1, is set.
[0040] At this time, as shown in Figure 8, in the lower half of the airfoil ring 38 in the second state, the second connecting line, with a distance L between the support point 40b on the outer surface of the lower half of the airfoil ring 38 and point VA2a on the second neutral axis VA2, is inclined by an angle α2 with respect to the horizontal line. Also, in the lower half of the airfoil ring 38 in the first state, with respect to the horizontal line, the support point 40a on the outer surface of the lower half of the airfoil ring 38 and point VA2a on the first neutral axis VA1 Point VA1aThe first connecting line, which has a distance L between it and the other, is a line that is inclined by an angle α1. Here, the relationship between the angles α1 and α2 of the connecting line is that the angles of the mounting surfaces 38a and 38b change between the lower half of the wing ring 38 in the first state and the lower half of the wing ring 38 in the second state. α1>α2 This is the result.
[0041] As a result, the vertical distance S2 between the support point 40b and point VA2a in the lower half of the blade ring 38 in the second state is different from the vertical distance S1 between the support point 40a and point VA1a in the lower half of the blade ring 38 in the first state. In other words, the relationship between distances S1 and S2 is S1 > S2, and when the lower half of the blade ring 38 moves from the second state to the first state, the lower half of the blade ring 38 moves vertically upward, and the vertical gap S at the bottom of the outer circumferential surface of the rotor 12 and the inner circumferential surface of the blade ring 34 decreases and becomes narrower.
[0042] If L is the distance between the support points 40a and 40b located on the outer surface of the lower half of the airfoil ring 38 and the neutral axes VA1 and VA2, α2 is the angle of the second connecting line (support point 40b - point VA2a) relative to the horizontal line, and Δα is the angle change from angle α2 to angle α1, then the gap change (gap change correction value) ΔSa can be calculated using the following formula. ΔSa=S1-S2=L×{sin(α2+Δα)-sinα2 } The angle change Δα can be calculated from the angle between the tangent to the first neutral axis VA1 at the support points 39a and 40a of the airfoil ring 34 in the first state, and the tangent to the second neutral axis VA2 at the support points 39b and 40b of the airfoil ring 34 in the second state, as shown in Figure 5 of the first embodiment.
[0043] Figure 9 is a flowchart illustrating the method for calculating the gap change in the blade ring in the second embodiment.
[0044] As shown in Figure 9, in step S31, CasingThe upper half 32 is removed. In step S32, the back surface measurement value H1 of the airfoil ring 34 is measured. In step S33, the upper half 37 of the airfoil ring is removed. In step S34, the back surface measurement value H2 of the airfoil ring 34 is measured. Then, in step S35, the gap change amount ΔS due to the change in radius of curvature is obtained by the above-described process (steps S11 to S21).
[0045] Furthermore, in step S41, the gap change amount ΔSa due to the distance between the support point and the neutral axis is obtained by the process described above. In step S42, the gap change amount ΔS is corrected by the gap change amount ΔSa, that is, by adding the gap change amount ΔSa to the gap change amount ΔS and recalculating, thereby correcting the gap change amount ΔS. Subsequently, when assembling the upper half of the airfoil ring 37, in step S36, the vertical position adjustment of the airfoil ring 34 is performed using the gap change amount ΔS.
[0046] [Effects of this embodiment] The first embodiment of the method for calculating the gap change amount of the airfoil ring includes the steps of: obtaining the amount of horizontal displacement of the airfoil ring 34 in a first state in which the upper half 37 of the airfoil ring is connected to the lower half 38 of the airfoil ring and in a second state in which the upper half 37 of the airfoil ring is removed from the lower half 38 of the airfoil ring; calculating the second neutral axis of the airfoil ring 34 in the second state based on the amount of displacement; and calculating the gap change amount between the first state and the second state by comparing the first neutral axis and the second neutral axis of the airfoil ring 34 in the first state.
[0047] According to the first embodiment of the method for calculating the gap change between the blade rings, assuming that the change in the back surface measurement value coincides with the change in the radius of curvature, that the neutral axes of the upper half 37 and lower half 38 of the blade ring 34 after assembly maintain a perfect circle, and that the arc length of the first neutral axis after assembly of the blade ring 34 coincides with the arc length of the second neutral axis before assembly, the change in the vertical gap between the outer surface of the rotor 12 and the inner surface of the blade ring 34 can be estimated. Casing This can improve the efficiency of assembly work.
[0048] The second embodiment of the method for calculating the gap change amount of the airfoil ring is the same as the first embodiment, further comprising: the first neutral axis of the airfoil ring 34 in the first state is calculated based on the design value or measured value of the airfoil ring 34; and the second neutral axis of the airfoil ring 34 in the second state is calculated based on the measured value of the airfoil ring 34. This makes it easy to calculate the first neutral axis and the second neutral axis.
[0049] The third embodiment of the method for calculating the gap change amount of the blade ring is the method for calculating the gap change amount of the blade ring according to the first embodiment or the second embodiment, further comprising two support points 39a, 39b, 40a, 40b that support the blade ring 34 from below, In the first state, it passes through the first neutral axis, and in the second state, it passes through the second neutral axis. This makes it easy to estimate the amount of change in the gap.
[0050] The fourth embodiment of the method for calculating the gap change amount of a blade ring is a method for calculating the gap change amount of a blade ring according to any one of the first to third embodiments, further comprising: calculating a vertical gap change amount correction value between the first state and the second state based on the angle of the first connecting line that connects the support points 39a, 39b, 40a, 40b that support the blade ring 34 from below to the first neutral axis with the shortest length, and the angle of the second connecting line that connects the support points 39a, 39b, 40a, 40b to the second neutral axis with the shortest length, and correcting the gap change amount with the gap change amount correction value. This makes it possible to calculate the gap change amount with high accuracy.
[0051] The fifth embodiment of the wing ring position adjustment method involves adjusting the vertical position of the wing ring 34 based on the gap change amount calculated by the wing ring gap change amount calculation method when assembling the upper half 37 of the wing ring to the lower half 38 of the wing ring. This allows for high-precision position adjustment of the wing ring 34. [Explanation of Symbols]
[0052] 10. Steam turbine (rotating machinery) 11 Casing 12 Rotor (rotating shaft) 13 Static Wings 14 Moving blade 31 Casing 32 Casing upper half 33 Casing lower half 34 Wing Ring 35 outside リング 36 inner リング 37 Upper part of the wing ring 38 Lower half of the wing ring 39,40 Support Department Support points 39a, 39b, 40a, 40b
Claims
1. In a method for calculating the gap change of a blade ring, in which a blade ring is formed by connecting the upper half and lower half of the blade ring to form a ring shape, the amount of change in the vertical gap between the inner circumferential surface of the blade ring and the outer circumferential surface of a rotation axis arranged inside the blade ring is calculated. A step of obtaining the amount of horizontal displacement of the wing ring in a first state in which the upper half of the wing ring is connected to the lower half of the wing ring and in a second state in which the upper half of the wing ring is detached from the lower half of the wing ring. A step of calculating the second neutral axis of the blade ring in the second state based on the amount of displacement, The steps include: calculating the amount of gap change between the first state and the second state by comparing the first neutral axis and the second neutral axis of the blade ring in the first state; A method for calculating the amount of gap change between airfoil rings having a particular airfoil ring.
2. The first neutral axis of the airfoil ring in the first state is calculated based on the design value or measured value of the airfoil ring, and the second neutral axis of the airfoil ring in the second state is calculated based on the measured value of the airfoil ring. A method for calculating the amount of gap change between airfoil rings according to claim 1.
3. The two support points that support the wing ring from below pass through the first neutral axis in the first state and through the second neutral axis in the second state. A method for calculating the amount of gap change between airfoil rings according to claim 1 or claim 2.
4. Based on the angle of the first connecting line connecting the support point supporting the airfoil ring from below and the first neutral axis with the shortest possible length, and the angle of the second connecting line connecting the support point and the second neutral axis with the shortest possible length, a vertical gap change correction value is calculated between the first state and the second state, and the gap change is corrected using the gap change correction value. A method for calculating the amount of gap change between airfoil rings according to claim 1.
5. When attaching the upper half of the wing ring to the lower half of the wing ring, The vertical position of the airfoil ring is adjusted based on the amount of gap change calculated by the method for calculating the amount of gap change of the airfoil ring described in claim 1. How to adjust the position of the wing rings.