JP2017198663A - Ultrasonic flaw detecting device, and ultrasonic flaw detecting method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an ultrasonic flaw detecting device that enables turbine rotors to undergo non-destructive examination without needing special skills or taking a long time.SOLUTION: A turbine rotor 9 having a blade groove 17 cut in the circumferential direction of the rotation axis has a disk face 9A directed in an axial direction parallel to the rotation axis of the turbine rotor and an inclined face 9C arranged farther outside than the disk face 9A in the diametric direction of the rotation axis. An ultrasonic flaw detecting device 100 is equipped with a first probe 22 and a second probe 24 that transmit ultrasonic beams to the corner parts 18 of the blade groove 17, a supporting device that supports the first probe 22 and the second probe 24 so that the first probe 22 can be disposed on the disk face 9A and the second probe 24 can be disposed on the inclined face 9C, and a control device 26 that detects the cracked state in the corner parts 18 on the basis of a reception signal of the second probe 24 having received echoes reflected by the corner parts 18. The supporting device shifts in the circumferential direction of the rotation axis in a state in which the first probe 22 is disposed on the disk face 9A and the second probe 24 is disposed on the inclined face 9C.SELECTED DRAWING: Figure 10

Description

  The present invention relates to an ultrasonic flaw detection apparatus and an ultrasonic flaw detection method for a turbine rotor.

  The steam turbine has a turbine rotor and a moving blade connected to a rotor disk of the turbine rotor. Known moving blades include a side-entry type moving blade having a so-called Christmas tree-shaped blade root portion, a T-root type moving blade having an alphabetic T-shaped blade root portion, and a Curtis-type moving blade. The rotor disk has a blade groove in which a blade root portion of a moving blade is disposed. The blade root portion of the rotor blade is disposed in the blade groove of the rotor disk, and the rotor disk and the rotor blade are fixed, whereby the turbine rotor and the rotor blade can rotate integrally.

  The turbine rotor is operated at high temperature conditions. For this reason, stress corrosion cracking (SCC) may occur in a portion of the rotor disk where repeated stress is applied due to long-term use. In the case of a rotor disk to which a T-root type moving blade is fixed, there is a high possibility that a crack will occur at the corner of the blade groove. As a non-destructive inspection technique for inspecting a crack state of a T root type rotor disk, an ultrasonic flaw detection inspection technique is known. Patent Document 1 discloses an ultrasonic flaw detection apparatus that inspects a turbine rotor by a phased array flaw detection method using a probe including a plurality of ultrasonic transducers. Patent Document 2 discloses an ultrasonic flaw detection apparatus that inspects a turbine rotor using a position monitoring probe and a flaw detection probe.

JP 2009-244079 A JP2013-68425A

  When inspecting the crack state of the T-root type rotor disk by the phased array flaw detection method, the size of the crack is evaluated from the difference between the echo reflected from the tip of the crack and the echo reflected from the corner of the blade groove. In order to detect the maximum size of the crack based on the echo reflected from the tip of the crack, the inspector transmits an ultrasonic beam from the probe while changing the angle and position of the probe. That is, the inspector carries out the inspection while swinging the probe and scanning it back and forth. The probe swing angle in the head scanning and the probe front / back scanning distance in the front / back scanning affect the detection accuracy of the crack size. If probe scanning is performed manually, the skill of the inspector performing the inspection is required. Further, when the scanning of the probe is performed manually, a great amount of inspection time is required.

  An object of the present invention is to provide an ultrasonic flaw detection apparatus and an ultrasonic flaw detection method for a turbine rotor that can perform nondestructive inspection in a short time without requiring skill.

  A first aspect of the present invention is an ultrasonic flaw detection apparatus that nondestructively inspects a rotor disk of a turbine rotor having blade grooves, wherein the blade grooves are provided in a circumferential direction of a rotating shaft of the turbine rotor, and the rotor The disk has a disk surface facing an axial direction parallel to the rotation axis, and an inclined surface disposed radially outward of the rotation axis with respect to the disk surface, and an angle of the blade groove of the rotor disk One of the first probe and the second probe for transmitting an ultrasonic beam to the section, and the first probe and the second probe are provided on the disk surface, and the other A support device that supports the first probe and the second probe so that the probe is provided on the inclined surface; and the second probe that receives the echo reflected from the corner portion. Control for detecting cracks at the corners based on received signals The support device moves in the circumferential direction of the rotating shaft in a state where one of the probes is provided on the disk surface and the other probe is provided on the inclined surface. An ultrasonic flaw detector is provided.

  According to this configuration, in a T-route type rotor disk in which blade grooves are provided in the circumferential direction and corner portions are provided in the blade grooves, an ultrasonic beam is provided when an inclined surface is provided radially outward from the disk surface. The first probe and the second probe in a state where one probe is provided on the disk surface and the other probe is provided on the inclined surface. By irradiating the corner of the blade groove with the ultrasonic beam transmitted from the probe and receiving the echo by the second probe, skill is required based on the received signal of the second probe Instead, the presence or absence of a crack and the size of the crack can be detected with high accuracy. Further, by moving one probe and the other probe in the circumferential direction, the state of cracks in the blade groove can be inspected with high accuracy over a wide range.

  The first aspect includes a first wedge member connected to one of the probes, and a second wedge member connected to the other probe, and the support device includes the one probe. It is preferable to have a first gimbal mechanism that movably supports the touch element and the first wedge member, and a second gimbal mechanism that movably supports the other probe and the second wedge member.

  One probe and the first wedge member are movably supported by the first gimbal mechanism, and the other probe and the second wedge member are movably supported by the second gimbal mechanism. When the member moves on the disk surface and the second wedge member moves on the inclined surface, the first wedge member can be made to follow the shape of the disk surface, and the second wedge member can be made to follow the shape of the inclined surface.

  In the first aspect, the support device includes a first holding member that holds one of the probes and the first wedge member, and a second holding that holds the other probe and the second wedge member. A member, the first holding member and the second holding member are fixed, a pair of frame members extending in a radial direction, and the frame member so as to face the disk surface and moving the support device It is preferable to have a driving roller to be driven and two driven rollers provided on the frame member so as to face the inclined surface.

  In the first aspect, it is preferable that a magnet is installed along the circumferential direction in the driving roller and the driven roller.

  In the first aspect, the frame member is preferably provided with a magnet along a length direction on a surface facing the disk surface.

  In the first aspect, the shaft portion of the driving roller is fixed at a predetermined position so as not to swing in a direction away from the disk surface in the out-of-plane direction, and the shaft portion of the driven roller is formed on the inclined surface. It is preferably fixed so as to be able to swing in a direction away from the surface in the out-of-plane direction.

  In the first aspect, the support device includes a first holding member that holds one of the probes and the first wedge member, and a second holding that holds the other probe and the second wedge member. It is preferable to have a member and a ball roller that can rotate in contact with the rotor disk.

  By providing the ball roller, the first wedge member can smoothly move on the disk surface, and the second wedge member can smoothly move on the inclined surface.

  Said 1st aspect WHEREIN: It is preferable that the said support apparatus has a position adjustment mechanism which can adjust the position of one said probe and said 1st wedge member in the radial direction of the said rotating shaft.

  By providing the position adjusting mechanism, the relative position between the irradiation region of the ultrasonic beam and the blade groove can be adjusted, and the inspection accuracy can be improved.

  In the first aspect, the position adjusting mechanism includes a guide portion provided on a pair of radially extending frame members, a nut inserted into the guide portion, and a bolt screwed to the nut. It is preferable that a protruding portion protruding inward on the opening side of the guide portion is sandwiched between the nut and the bolt.

  In the first aspect, a supply device is provided that supplies a contact medium to each of a gap between the surface of the first wedge member and the disk surface and a gap between the surface of the second wedge member and the inclined surface. preferable.

  An inclination between the surface of the first wedge member and the disk surface facing the surface of the first wedge member through a gap, and the surface of the second wedge member and the surface of the second wedge member facing through a gap. By supplying a contact medium such as water or oil to each of the surfaces, an ultrasonic beam emitted from one probe and emitted from the surface of the first wedge member, and the other probe Each of the ultrasonic beams emitted from the child and emitted from the surface of the second wedge member is efficiently transmitted to the corners of the blade groove.

  A second aspect of the present invention is an ultrasonic flaw detection method for nondestructive inspection of a rotor disk of a turbine rotor having blade grooves, wherein the blade grooves are provided in a circumferential direction of a rotating shaft of the turbine rotor, and the rotor The disk has a disk surface facing an axial direction parallel to the rotation axis, and an inclined surface disposed radially outward of the rotation axis with respect to the disk surface, and an angle of the blade groove of the rotor disk A step of providing either one of a first probe and a second probe for transmitting an ultrasonic beam on the disk surface on the disk surface; and the first probe and the second probe Providing the other probe on the inclined surface, detecting a crack state at the corner based on a received signal of the second probe that has received an echo reflected at the corner, The probe is set on the disk surface. Moving the first probe and the second probe in the circumferential direction of the rotating shaft in a state where the other probe is provided on the inclined surface. Provided.

  According to this configuration, in a T-route type rotor disk in which blade grooves are provided in the circumferential direction and corner portions are provided in the blade grooves, an ultrasonic beam is provided when an inclined surface is provided radially outward from the disk surface. The first probe and the second probe in a state where one probe is provided on the disk surface and the other probe is provided on the inclined surface. By irradiating the corner of the blade groove with the ultrasonic beam transmitted from the probe and receiving the echo by the second probe, skill is required based on the received signal of the second probe Instead, the presence or absence of a crack and the size of the crack can be detected with high accuracy. Further, by moving one probe and the other probe in the circumferential direction, the state of cracks in the blade groove can be inspected with high accuracy over a wide range.

  ADVANTAGE OF THE INVENTION According to this invention, the ultrasonic flaw detection apparatus and ultrasonic flaw detection method of a turbine rotor which can perform a nondestructive inspection in a short time without requiring a skill are provided.

FIG. 1 is a diagram schematically illustrating an example of a rotating machine according to the present embodiment. FIG. 2 is a perspective view showing a part of the rotor blade and the rotor disk according to the present embodiment. FIG. 3 is a sectional view showing a part of the rotor blade and the rotor disk according to the present embodiment. FIG. 4 is a perspective view schematically showing an example of the ultrasonic flaw detector according to the present embodiment. FIG. 5 is a cross-sectional view schematically showing an example of the ultrasonic flaw detector according to the present embodiment. FIG. 6 is a perspective view schematically showing an example of the ultrasonic flaw detector according to the present embodiment. FIG. 7 is a cross-sectional view schematically showing an example of the ultrasonic flaw detector according to the present embodiment. FIG. 8 is a perspective view schematically showing an example of the ultrasonic flaw detector according to the present embodiment. FIG. 9 is a cross-sectional view schematically showing an example of the ultrasonic flaw detector according to the present embodiment. FIG. 10 is a perspective view schematically showing an example of the ultrasonic flaw detector according to the present embodiment. FIG. 11 is a cross-sectional view schematically showing an example of the ultrasonic flaw detector according to the present embodiment. FIG. 12 is a schematic diagram showing an example of an ultrasonic flaw detector according to this embodiment. FIG. 13 is a perspective view showing a first specific example of the ultrasonic flaw detector according to the present embodiment. FIG. 14 is a front view showing a first specific example of the ultrasonic flaw detector according to the present embodiment. FIG. 15 is a longitudinal sectional view showing a first specific example of the ultrasonic flaw detector according to the present embodiment. FIG. 16 is a side view showing a first specific example of the ultrasonic flaw detector according to the present embodiment. FIG. 17 is a cross-sectional view showing a position adjusting mechanism of the ultrasonic flaw detector according to the present embodiment. FIG. 18 is a perspective view showing a second specific example of the ultrasonic flaw detector according to the present embodiment. FIG. 19 is a front view showing a second specific example of the ultrasonic flaw detector according to the present embodiment. FIG. 20 is a longitudinal sectional view showing a second specific example of the ultrasonic flaw detector according to this embodiment. FIG. 21 is a side view showing a second specific example of the ultrasonic flaw detector according to the present embodiment. FIG. 22 is a cross-sectional view showing a scale indicator plate of the ultrasonic flaw detector according to the present embodiment.

  Hereinafter, embodiments according to the present invention will be described with reference to the drawings, but the present invention is not limited thereto. In addition, the constituent elements in the embodiments described below can be combined as appropriate. Some components may not be used.

[Rotating machinery]
FIG. 1 is a diagram schematically illustrating an example of a rotating machine 1 according to the present embodiment. In the present embodiment, an example in which the rotary machine 1 is a steam turbine will be described. The rotating machine 1 may be a gas turbine or a compressor.

  As shown in FIG. 1, a rotary machine 1 as a steam turbine is disposed around a turbine rotor 2 that can rotate around a rotation axis AX, a moving blade 5 that is fixed to the turbine rotor 2, and the turbine rotor 2. The stator 3 is provided. The turbine rotor 2 includes a shaft member 4 that can rotate about a rotation axis AX, and a rotor disk 9 that is fixed to the shaft member 4. The stator 3 includes a casing 6 and a stationary blade 7 provided on the casing 6.

  In the following description, a direction parallel to the rotation axis AX of the turbine rotor 2 is appropriately referred to as a width direction, and a radial direction with respect to the rotation axis AX of the turbine rotor 2 is appropriately referred to as a radial direction. A rotation direction around the axis AX is appropriately referred to as a circumferential direction. In addition, a position far from or away from the rotation axis AX in the radial direction is appropriately referred to as a radially outer side, and a position closer to or closer to the rotation axis AX in the radial direction is appropriately referred to as a radially inner side.

  The turbine rotor 2 is rotatably supported by the casing 6 through a bearing 8. At least a part of the turbine rotor 2 is disposed inside the casing 6. The moving blade 5 is fixed to the rotor disk 9 of the turbine rotor 2. A plurality of moving blades 5 are arranged in the circumferential direction. The moving blades 5 are arranged in a plurality of stages in the axial direction.

  A plurality of stationary blades 7 are arranged in the circumferential direction. The stationary blades 7 are arranged in a plurality of stages in the axial direction. The moving blades 5 are arranged in a plurality of stages at predetermined intervals in the axial direction. The stationary blades 7 are arranged in multiple stages so as to be arranged between the moving blades 5 in the axial direction.

  The casing 6 includes a steam passage 10 in which the moving blade 5 and the stationary blade 7 are disposed, a steam supply port 11 that supplies steam to the steam passage 10, and a steam discharge port 12 that discharges steam in the steam passage 10. The steam supplied from the steam supply port 11 flows through the steam passage 10 while being in contact with the moving blade 5 and the stationary blade 7. When the steam comes into contact with the moving blade 5, the turbine rotor 2 rotates about the rotation axis AX. When the turbine rotor 2 rotates, the generator connected to the shaft member 4 is driven. The steam that has flowed through the steam passage 10 is discharged from the steam outlet 12.

[Rotating blades and rotor disks]
FIG. 2 is a perspective view showing a part of the rotor blade 5 and the rotor disk 9 according to the present embodiment. FIG. 3 is a cross-sectional view showing a part of the rotor blade 5 and the rotor disk 9 according to the present embodiment.

  As shown in FIGS. 2 and 3, the moving blade 5 has a blade portion 15 and a blade root portion 13 fixed to the rotor disk 9. In the present embodiment, the moving blade 5 is a T root type moving blade having an alphabetic T-shaped blade root portion 13. A plurality of moving blades 5 are provided in the circumferential direction. The blade root portion 13 is disposed in a blade groove 17 provided in the rotor disk 9. The blade groove 17 is provided in the circumferential direction.

  The blade root portion 13 includes a neck portion 14 and an enlarged portion 16 that is disposed radially inward of the neck portion 14 and has a larger axial dimension than the neck portion 14.

  The rotor disk 9 has a blade groove 17 in which the blade root portion 13 is disposed. The blade groove 17 has a plurality of corners 18. As shown in FIG. 3, in the present embodiment, the corner 18 includes a first corner 18A, a second corner 18B, a third corner 18C, and a fourth corner 18D. The first corner 18A and the second corner 18B are disposed in the axial direction. The third corner 18C and the fourth corner 18D are arranged in the axial direction. The first corner portion 18A is disposed on the outer side in the radial direction than the third corner portion 18C. The second corner 18B is disposed on the outer side in the radial direction than the fourth corner 18D.

  The blade root portion 13 of the rotor blade 5 is disposed in the blade groove 17 of the rotor disk 9 and the rotor disk 9 and the rotor blade 5 are fixed, so that the turbine rotor 2 and the rotor blade 5 can rotate integrally. .

  In this embodiment, the rotor disk 9 supports a T-root type moving blade. As shown in FIG. 3, the rotor disk 9 includes a disk surface 9A that faces one side in the axial direction, a disk surface 9B that faces the other side in the axial direction, and a disk surface 9A that is disposed radially outside the disk surface 9A. And an inclined surface 9D that is disposed radially outside the disk surface 9B and connected to the disk surface 9B.

  In the present embodiment, each of the disk surface 9A and the disk surface 9B is a flat surface that is substantially orthogonal to the rotation axis AX. The inclined surface 9C and the inclined surface 9D are inclined so as to approach the center line ML toward the radially outer side.

  The center line ML is an imaginary line passing through the center of the rotor disk 9 in the axial direction out of the radiation of the rotation axis AX.

  Further, the rotor disk 9 has a thick portion 91 provided on the radially outer side than the inclined surface 9C, and a thick portion 92 provided on the radially outer side than the inclined surface 9D.

  There is a possibility that stress corrosion cracks (SCC) may occur in the rotor disk 9. For example, as shown in FIG. 3, crack 19 may occur in rotor disk 9 starting from corner 18 of blade groove 17. The crack 19 is likely to grow radially outward from the corner 18. FIG. 8 shows a crack 19 that starts from the first corner 18A. The crack 19 may occur not only from the first corner 18A but also from at least one of the second corner 18B, the third corner 18C, and the fourth corner 18D.

  In this embodiment, the ultrasonic flaw detector 100 is used to inspect the state of the crack 19 generated in the rotor disk 9 in a nondestructive manner. In the present embodiment, the ultrasonic flaw detector 100 inspects the state of the crack 19 in the rotor disk 9 by a TOFD (Time Of Flight Diffraction) flaw detection method and a phased array flaw detection method.

[Outline of Ultrasonic Flaw Detector: First Example]
Next, a first example of the outline of the ultrasonic flaw detector 100 according to the present embodiment will be described. FIG. 4 is a perspective view schematically showing an example of the ultrasonic flaw detector 100 according to the first embodiment. FIG. 5 is a cross-sectional view schematically showing an example of the ultrasonic flaw detector 100 according to the first embodiment. As shown in FIGS. 4 and 5, the ultrasonic flaw detector 100 includes a first probe 22 that transmits an ultrasonic beam to the first corner 18 </ b> A of the blade groove 17 of the rotor disk 9, and the first of the blade groove 17. It has the 2nd probe 24 which transmits an ultrasonic beam to 18 A of corner parts, and the control apparatus 26 which controls the 1st probe 22 and the 2nd probe 24. FIG.

  The first probe 22 and the second probe 24 are arranged so as to face each other with the first corner portion 18A that is a flaw detection site interposed therebetween. In the first embodiment, the first probe 22 and the second probe 24 are arranged in the radial direction. In the radial direction, the first probe 22 and the second probe 24 face each other. In the radial direction, a first corner portion 18 </ b> A that is a flaw detection site is disposed between the first probe 22 and the second probe 24. In the first embodiment, both the first probe 22 and the second probe 24 are arranged on the disk surface 9A.

  Each of the first probe 22 and the second probe 24 is a phased array probe including a plurality of ultrasonic transducers. The control device 26 can transmit an ultrasonic beam from the first probe 22 by applying an excitation voltage to each of the plurality of ultrasonic transducers of the first probe 22. Similarly, the control device 26 can transmit an ultrasonic beam from the second probe 24 by applying an excitation voltage to each of the plurality of ultrasonic transducers of the second probe 24.

  The first probe 22 transmits an ultrasonic beam. The ultrasonic beam transmitted from the first probe 22 is irradiated to the flaw detection site of the rotor disk 9. The control device 26 controls the excitation voltage applied to the plurality of ultrasonic transducers of the first probe 22 and scans the ultrasonic beam transmitted from the first probe 22. The first probe 22 scans the ultrasonic beam along a plane passing through the rotation axis AX. As shown in FIG. 5, the ultrasonic flaw detector 100 scans an ultrasonic beam to form a radial (fan-shaped) detection area SA. The detection area SA is an area through which the ultrasonic beam transmitted from the first probe 22 passes.

  The second probe 24 transmits an ultrasonic beam. The ultrasonic beam transmitted from the second probe 24 is applied to the flaw detection site of the rotor disk 9. The control device 26 controls the excitation voltage applied to the plurality of ultrasonic transducers of the second probe 24 and scans the ultrasonic beam transmitted from the second probe 24. The second probe 24 scans the ultrasonic beam along a plane passing through the rotation axis AX. As shown in FIG. 5, the ultrasonic flaw detector 100 scans an ultrasonic beam to form a radial (fan-shaped) detection area SA. The detection area SA is an area through which the ultrasonic beam transmitted from the second probe 24 passes.

  The second probe 24 receives the echo reflected from the flaw detection site when the flaw detection site of the rotor disk 9 is irradiated with the ultrasonic beam. That is, in the present embodiment, the ultrasonic beam is irradiated from both the first probe 22 and the second probe 24 onto the first corner portion 18A that is the flaw detection portion of the rotor disk 9. The control device 26 simultaneously performs the emission of the ultrasonic beam from the first probe 22 to the first corner 18A and the emission of the ultrasonic beam from the second probe 24 to the first corner 18A. . The echo generated by the first corner portion 18A by being irradiated with the ultrasonic beam is received by the second probe 24.

  The control device 26 detects the state of the crack 19 in the first corner 18A based on the reception signal of the second probe 24 that has received the echo reflected by the first corner 18A. The control device 26 detects, for example, the size of the crack 19 based on the reception signal of the second probe 24 that has received the echo.

  Note that the first probe 22 may receive an echo generated by the first corner portion 18 </ b> A by being irradiated with the ultrasonic beam. The control device 26 may detect the state of the crack 19 in the first corner 18A based on the reception signal of the first probe 22 that has received the echo reflected by the first corner 18A.

  Thus, in the present embodiment, the first probe 22 and the second probe 24 that are phased array probes are arranged to face each other, and the first probe 22 and the second probe 24 are arranged. In the state where the first corner 18A, which is a flaw detection site, is disposed between the first probe 22 and the second probe 24, an ultrasonic beam is transmitted to the first corner 18A, and the first corner 18A is transmitted to the first corner 18A. At least one of the probe 22 and the second probe 24 receives an echo. The control device 26 detects the state of the crack 19 based on the reception signal of at least one of the first probe 22 and the second probe 24 that has received the echo. Accordingly, the relative position between the first probe 22 and the second probe 24 can be adjusted with high accuracy, the installation position and the installation angle of the first probe 22 can be adjusted with high accuracy, The size of the crack 19 can be detected without adjusting the installation position and the installation angle of the probe 24 with high accuracy.

  The first probe 22 and the second probe 24 are movable in the radial direction. At least one of the first probe 22 and the second probe 24 moves in the radial direction on the disk surface 9A, and the relative position between the first probe 22 and the second probe 24 in the radial direction changes. Thus, the ultrasonic beam is irradiated over a wide range. By moving at least one of the first probe 22 and the second probe 24 in the radial direction, the corner 18 can be flawed over a wide range with a small detection area SA.

  Further, by moving the first probe 22 and the second probe 24 together in the circumferential direction, the blade groove 17 arranged in the circumferential direction can be flawed over a wide range.

[Overview of ultrasonic flaw detector: second embodiment]
Next, a second example of the outline of the ultrasonic flaw detector 100 according to the present embodiment will be described. FIG. 6 is a perspective view schematically showing an example of the ultrasonic flaw detector 100 according to the second embodiment. FIG. 7 is a cross-sectional view schematically showing an example of the ultrasonic flaw detector 100 according to the second embodiment.

  The first probe 22 and the second probe 24 are arranged so as to face each other across the flaw detection site of the first corner 18A. In the second embodiment, the first probe 22 and the second probe 24 are arranged in the circumferential direction. In the circumferential direction, the first probe 22 and the second probe 24 face each other. In the circumferential direction, the flaw detection site of the first corner portion 18A is disposed between the first probe 22 and the second probe 24. In the second embodiment, both the first probe 22 and the second probe 24 are arranged on the disk surface 9A.

  Also in the second embodiment, the first probe 22 and the second probe 24 that are phased array probes are arranged to face each other, and between the first probe 22 and the second probe 24. In a state where the flaw detection site of the first corner portion 18A is disposed, an ultrasonic beam is transmitted from both the first probe 22 and the second probe 24 to the flaw detection site, and the first probe 22 and the second probe At least one of the probes 24 receives an echo. The control device 26 detects the state of the crack 19 based on the reception signal of at least one of the first probe 22 and the second probe 24 that has received the echo. Also in the second embodiment, the relative position between the first probe 22 and the second probe 24 is adjusted with high accuracy, and the installation position and the installation angle of the first probe 22 are adjusted with high accuracy. In addition, the size of the crack 19 can be detected without adjusting the installation position and the installation angle of the second probe 24 with high accuracy.

  The first probe 22 and the second probe 24 are relatively movable in the circumferential direction. At least one of the first probe 22 and the second probe 24 moves in the circumferential direction on the disk surface 9A, and the relative position between the first probe 22 and the second probe 24 in the circumferential direction changes. Thus, the ultrasonic beam is irradiated over a wide range. By moving at least one of the first probe 22 and the second probe 24 in the circumferential direction, the corner 18 can be flawed over a wide range with a small detection area SA.

  Further, by moving the first probe 22 and the second probe 24 together in the circumferential direction, the blade groove 17 arranged in the circumferential direction can be flawed over a wide range.

[Overview of ultrasonic flaw detector: third embodiment]
Next, a third example of the outline of the ultrasonic flaw detector 100 according to the present embodiment will be described. FIG. 8 is a perspective view schematically showing an example of the ultrasonic flaw detector 100 according to the third embodiment. FIG. 9 is a cross-sectional view schematically showing an example of the ultrasonic flaw detector 100 according to the third embodiment.

  In the third embodiment, a first ultrasonic transducer 22A that functions as the first probe 22 and a second ultrasonic transducer 24A that functions as the second probe 24 are supported by one housing 20. Is integrated. The first ultrasonic transducer 22A and the second ultrasonic transducer 24A are arranged so as to face each other across the flaw detection site of the first corner 18A. In the third embodiment, the first ultrasonic transducer 22A and the second ultrasonic transducer 24A are arranged in the radial direction. In the radial direction, the first ultrasonic transducer 22A and the second ultrasonic transducer 24A face each other. In the radial direction, the flaw detection site of the first corner 18A is disposed between the first ultrasonic transducer 22A and the second ultrasonic transducer 24A. In the third embodiment, both the first ultrasonic transducer 22A and the second ultrasonic transducer 24A are disposed on the disk surface 9A. The first ultrasonic transducer 22A and the second ultrasonic transducer 24A may be arranged in the circumferential direction.

  Also in the third embodiment, the first ultrasonic transducer 22A and the second ultrasonic transducer 24A are arranged to face each other, and the first corner portion is provided between the first ultrasonic transducer 22A and the second ultrasonic transducer 24A. In a state where the 18A flaw detection site is arranged, an ultrasonic beam is transmitted from both the first ultrasonic transducer 22A and the second ultrasonic transducer 24A to the flaw detection site, and the first ultrasonic transducer 22A and the second ultrasonic transducer 22A are transmitted. At least one of the acoustic transducers 24A receives an echo. The control device 26 detects the state of the crack 19 based on the reception signal of at least one of the first ultrasonic transducer 22A and the second ultrasonic transducer 24A that has received the echo.

[Outline of ultrasonic flaw detector: Fourth embodiment]
Next, the outline | summary 4th Example of the ultrasonic flaw detector 100 which concerns on this embodiment is demonstrated. FIG. 10 is a perspective view schematically showing an example of the ultrasonic flaw detector 100 according to the fourth embodiment. FIG. 11 is a cross-sectional view schematically showing an example of the ultrasonic flaw detector 100 according to the fourth embodiment.

  The first probe 22 and the second probe 24 are arranged so as to face each other across the flaw detection site of the first corner 18A. In the fourth embodiment, the first probe 22 and the second probe 24 are arranged in the circumferential direction. In the circumferential direction, the first probe 22 and the second probe 24 face each other. In the circumferential direction, the flaw detection site of the first corner portion 18A is disposed between the first probe 22 and the second probe 24. In the fourth embodiment, the first probe 22 is provided on the disk surface 9A, and the second probe 24 is provided on the inclined surface 9C.

  Also in the fourth embodiment, the first probe 22 and the second probe 24 that are phased array probes are arranged to face each other, and between the first probe 22 and the second probe 24. In a state where the flaw detection site of the first corner portion 18A is disposed, an ultrasonic beam is transmitted from both the first probe 22 and the second probe 24 to the flaw detection site, and the first probe 22 and the second probe At least one of the probes 24 receives an echo. The control device 26 detects the state of the crack 19 based on the reception signal of at least one of the first probe 22 and the second probe 24 that has received the echo. Also in the fourth embodiment, the relative position between the first probe 22 and the second probe 24 is adjusted with high accuracy, and the installation position and installation angle of the first probe 22 are adjusted with high accuracy. In addition, the size of the crack 19 can be detected without adjusting the installation position and the installation angle of the second probe 24 with high accuracy.

  Also in the fourth embodiment, the first probe 22 and the second probe 24 are movable in the radial direction. At least one of the movement of the first probe 22 on the inclined surface 9C and the movement of the second probe 24 on the disk surface 9A is performed, and the first probe 22 and the second probe 24 in the radial direction are moved. By changing the relative position, the ultrasonic beam is irradiated over a wide range. By moving at least one of the first probe 22 and the second probe 24 in the radial direction, the corner 18 can be flawed over a wide range with a small detection area SA.

  Further, by moving the first probe 22 and the second probe 24 together in the circumferential direction, the blade groove 17 arranged in the circumferential direction can be flawed over a wide range.

[Specific example of ultrasonic flaw detector]
Next, a specific example of the ultrasonic flaw detector 100 according to the present embodiment will be described. FIG. 12 is a schematic diagram illustrating a first specific example of the ultrasonic flaw detector 100 according to the present embodiment. FIG. 13 is a perspective view showing a first specific example of the ultrasonic flaw detector 100 according to the present embodiment. FIG. 14 is a front view showing a first specific example of the ultrasonic flaw detector 100 according to the present embodiment. FIG. 15 is a longitudinal sectional view showing a first specific example of the ultrasonic flaw detector 100 according to the present embodiment. FIG. 16 is a side view showing a first specific example of the ultrasonic flaw detector 100 according to the present embodiment.

  As shown in FIGS. 12 to 16, in the present embodiment, the first probe 22 is provided on the disk surface 9A, and the second probe 24 is provided on the inclined surface 9C.

  In the ultrasonic flaw detector 100, the first probe 22 and the second probe 24 are provided such that the first probe 22 is provided on the disk surface 9A and the second probe 24 is provided on the inclined surface 9C. And a control device that detects the state of the crack 19 in the corner 18 based on the received signal of the second probe 24 that has received the echo reflected by the corner 18 (first corner 18A). 26.

  In the present embodiment, the ultrasonic flaw detector 100 includes a first wedge member 22W connected to the first probe 22 and a second wedge member 24W connected to the second probe 24. The support device 30 supports the first probe 22 and the first wedge member 22W so that the first wedge member 22W faces the disk surface 9A. The support device 30 supports the second probe 24 and the second wedge member 24W so that the second wedge member 24W faces the inclined surface 9C. The first probe 22 irradiates the rotor disk 9 with an ultrasonic beam via the first wedge member 22W. The second probe 24 irradiates the rotor disk 9 with an ultrasonic beam via the second wedge member 24W.

  The support device 30 is configured so that the beam transmitted from the first probe 22 and the beam transmitted from the second probe 24 are irradiated to the flaw detection site of the blade groove 17. With the first wedge member 22W provided on the disk surface 9A and the second probe 24 and the second wedge member 24W provided on the inclined surface 9C, the first probe 22, the first wedge member 22W, The two probes 24 and the second wedge member 24W are supported and moved in the circumferential direction.

  The support device 30 includes a first holding member 32 that holds the first probe 22 and the first wedge member 22W, a second holding member 34 that holds the second probe 24 and the second wedge member 24W, And a main body member 31 that supports the first holding member 32 and the second holding member 34.

  Further, the support device 30 can adjust the position of the first probe 22 and the first wedge member 22W in the radial direction or the position of the second probe 24 and the second wedge member 24W in the radial direction. It has a mechanism 36.

  The main body member 31 includes a pair of frame members 31A and 31B extending in the radial direction, and a connecting member 33 that connects the frame member 31A and the frame member 31B.

  The position adjustment mechanism 36 includes a guide portion 36G provided on the frame members 31A and 31B. The first holding member 32 and the second holding member 34 are movable in the radial direction while being guided by the guide portion 36G. When the first holding member 32 and the second holding member 34 are disposed at arbitrary positions in the radial direction, the first holding member 32 or the second holding member 34 and the frame members 31A and 31B are fixed. As a result, the position of the first holding member 32 or the second holding member 34 in the radial direction is fixed. By adjusting the position of the first holding member 32 or the second holding member 34, the position of the first probe 22 and the first wedge member 22W in the radial direction, or the second probe 24 and the second wedge. The position of the member 24W is adjusted.

  As shown in FIG. 17, the position adjustment mechanism 36 includes a bolt 58 and a nut 59. Moreover, the guide part 36G provided in frame member 31A, 31B has the protrusion part 37 which protruded inside in the opening side. The diameter of the nut 59 is longer than the opening width of the guide portion 36G. The nut 59 can be inserted from one end of the guide portion 36G. The nut 59 is disposed inside the groove of the guide portion 36G, and by tightening the bolt 58, the nut 59 is pulled up to the opening side of the guide portion 36G. The position of the first holding member 32 or the second holding member 34 is fixed by sandwiching the protruding portion 37 of the guide portion 36G by the bolt 58 and the nut 59. Even when the bolt 58 is loosened, the first holding member 32 or the second holding member 34 is unlikely to fall off the guide portion 36G unless it is removed from the nut 59.

  The support device 30 includes a ball roller 38 and a driven roller 39 that movably support the main body member 31, a motor 41 having a motor 41 and a driving roller 42 driven by the motor 41, an encoder 71, and an encoder roller 72. Encoder unit 70 having The motor unit 40 and the encoder unit 70 are supported by the main body member 31.

  As shown in FIG. 13, the ball roller 38 is supported by the main body member 31 via a support mechanism 38C. The ball roller 38 travels on the disk surface 9A in the circumferential direction. The ball roller 38 is made of, for example, a nonmagnetic material. By adopting the ball roller 38 instead of the roller rotating about only one axis, it is possible to easily cope with the rotor disk 9 having different radii without adjusting. As a result, the ultrasonic flaw detector 100 can be reliably moved along the circumferential direction. Further, the ball roller 38 can reduce the resistance when the ultrasonic flaw detector 100 moves as compared with a roller that rotates about only one axis.

  The driven roller 39 is supported by the main body member 31 via a support mechanism 39C. The driven roller 39 travels on the inclined surface 9C in the circumferential direction. The support mechanism 39C includes a swing mechanism, and the driven roller 39 can follow the tilt angle of the inclined surface 9C and the curvature (circumferential shape) of the rotor disk 9 by the swing mechanism. Further, it is desirable that the shaft portion of the encoder roller 72 is fixed by a swing mechanism so as to be swingable in a direction away from the disk surface 9A of the rotor disk 9 in the out-of-plane direction. Thereby, resistance can be reduced compared with the case where the axial part of the encoder roller 72 is fixed.

  The driven roller 39 has a disk shape and rotates around one axis. A groove having a concave cross section is formed in the driven roller 39 along the circumferential direction, and a magnet is installed in the groove along the circumferential direction. The magnet is, for example, neodymium, and is installed on the driven roller 39 so as not to come into contact with the inclined surface 9C of the rotor disk 9. Accordingly, when the ultrasonic flaw detector 100 is moved, the ultrasonic flaw detector 100 is unlikely to be separated from the inclined surface 9C of the rotor disk 9 in the out-of-plane direction.

  The support mechanism 39C further includes an adjustment mechanism, and can adjust the fixed angle of the driven roller 39. By changing the fixed angle of the driven roller 39 by the adjusting mechanism, it is possible to deal with the rotor disk 9 having different radii and the rotor disk 9 having a different inclination angle of the inclined surface 9C.

  The motor unit 40 includes a motor 41 and a driving roller 42 that is rotated by the power generated by the motor 41. The drive roller 42 travels on the disk surface 9A in the circumferential direction. When the drive roller 42 is rotated by the operation of the motor 41, the main body member 31 moves in the circumferential direction. When the main body member 31 moves in the circumferential direction, the first probe 22, the first wedge member 22W, the second probe 24, and the second wedge member 24W move in the circumferential direction together with the main body member 31. The relative positions of the first probe 22 and the first wedge member 22W and the rotor disk 9 in the circumferential direction are adjusted by the motor unit 40, and the second probe 24 and the second wedge member 24W and the rotor disk in the circumferential direction are adjusted. The relative position with respect to 9 is adjusted. By providing the motor unit 40, automatic flaw detection becomes possible.

  The drive roller 42 of the motor unit 40 has a disk shape and rotates around one axis. A groove having a concave cross section is formed in the drive roller 42 along the circumferential direction, and a magnet is installed in the groove along the circumferential direction. The magnet is, for example, neodymium, and is installed on the drive roller 42 so as not to contact the disk surface 9A of the rotor disk 9 so as to be separated from the disk surface 9A. Accordingly, when the ultrasonic flaw detector 100 is moved, the ultrasonic flaw detector 100 is unlikely to be separated from the disk surface 9A of the rotor disk 9 in the out-of-plane direction.

  The shaft portion of the drive roller 42 is preferably fixed at a predetermined position so as not to swing in a direction away from the disk surface 9A of the rotor disk 9 in the out-of-plane direction. Thereby, idling of the drive roller 42 can be prevented.

  The two driven rollers 39 and the drive roller 42 are provided with magnets along the circumferential direction as described above, and the ultrasonic flaw detector 100 is supported at three points with respect to the rotor disk 9 and stably supported. Is done. When the driving roller 42 is rotated by the operation of the motor 41, the driving roller 42 moves straight, but by the three-point support by the two driven rollers 39 and the driving roller 42, the ultrasonic flaw detection apparatus 100 causes the rotor disk 9 to rotate. Can be reliably rotated along the circumferential direction.

  The encoder unit 70 has an encoder roller 72 that rotates on the disk surface 9A. The amount of rotation of the encoder roller 72 is detected by the encoder 71. The encoder unit 70 can detect the movement amount of the main body member 31 in the circumferential direction based on the rotation amount of the encoder roller 72.

  The encoder roller 72 of the encoder unit 70 has a disk shape and rotates around one axis. A groove having a concave cross section is formed in the encoder roller 72 along the circumferential direction, and a magnet is installed in the groove along the circumferential direction. The magnet is, for example, neodymium, and is installed on the encoder roller 72 so as not to contact with the disk surface 9A of the rotor disk 9 apart from the disk surface 9A. Accordingly, when the ultrasonic flaw detector 100 is moved, the ultrasonic flaw detector 100 is unlikely to be separated from the disk surface 9A of the rotor disk 9 in the out-of-plane direction.

  It is desirable that the shaft portion of the encoder roller 72 of the encoder unit 70 is fixed so as to be swingable in a direction away from the disk surface 9A of the rotor disk 9 in the out-of-plane direction. As a result, the resistance can be reduced as compared with the case where the shaft portion of the encoder roller 72 is fixed, and the three-point support of the two driven rollers 39 and the driving roller 42 described above is easily realized. The surface of the encoder unit 70 on the disk surface 9A side is subjected to anti-slip processing such as knurling. As a result, the ultrasonic flaw detector 100 can easily reliably rotate along the circumferential direction of the rotor disk 9.

  The support device 30 includes a ball roller 38 and a driven roller 39 that are rotatable in contact with the rotor disk 9. By the ball roller 38 and the driven roller 39, the main body member 31 and the first holding member 32 and the second holding member 34 supported by the main body member 31 can travel on the disk surface 9A and the inclined surface 9C in the circumferential direction. is there. Further, the ball roller 38 and the disk surface 9A are in contact with each other, and the driven roller 39 and the inclined surface 9C are in contact with each other, whereby the disk surface 9A and the surface of the first wedge member 22W facing the disk surface 9A are interposed. A gap is formed between the inclined surface 9C and the surface of the second wedge member 24W facing the inclined surface 9C.

  Further, the support device 30 supports the first probe 22 and the first wedge member 22W to be movable, and the second probe 24 and the second wedge member 24W to be movable. And a second gimbal mechanism 54.

  The first gimbal mechanism 52 is provided between the main body member 31, and the first probe 22 and the first wedge member 22W, and supports the first probe 22 and the first wedge member 22W so as to be movable. In the present embodiment, the first gimbal mechanism 52 is provided on the first holding member 32. The first holding member 32 is movable relative to the main body member 31. The first gimbal mechanism 52 rotatably supports the first probe 22 and the first wedge member 22W around two axes including at least a first roll axis and a first pitch axis orthogonal to the first roll axis. .

  The second gimbal mechanism 54 is provided between the main body member 31 and the second probe 24 and the second wedge member 24W, and movably supports the second probe 24 and the second wedge member 24W. In the present embodiment, the second gimbal mechanism 54 is provided on the second holding member 34. The second holding member 34 can move relative to the main body member 31. The second gimbal mechanism 54 rotatably supports the second probe 24 and the second wedge member 24W around two axes including at least a second roll axis and a second pitch axis orthogonal to the second roll axis. .

  Each of the first holding member 32 and the second holding member 34 has a magnet. The magnet is provided on the first holding member 32 so as to face the disk surface 9A. The magnet is provided on the second holding member 34 so as to face the inclined surface 9C.

  Each of the frame members 31 </ b> A and 31 </ b> B has a magnet 43. The magnet 43 is provided so as to face the disk surface 9A along the length direction of the frame members 31A and 31B. The magnet 43 is spaced apart from the disk surface 9A of the rotor disk 9 and is installed on the frame members 31A and 31B so as not to contact. Thereby, while reducing the resistance when the ultrasonic flaw detector 100 moves, the ultrasonic flaw detector 100 becomes difficult to separate from the disk surface 9A in the out-of-plane direction when the ultrasonic flaw detector 100 moves.

  On the inside of the frame member 31A and the frame member 31B of the main body member 31, that is, on the first holding member 32 side or the second holding member 34 side, a number that functions as a scale may be written. Thereby, position adjustment of the 1st probe 22 and the 2nd probe 24 can be performed simply.

  As shown in FIG. 12, the support device 30 applies contact media to the gap between the surface of the first wedge member 22W and the disk surface 9A and the gap between the surface of the second wedge member 24W and the inclined surface 9C. A supply device 66 is provided. The contact medium includes water or oil.

  Next, an ultrasonic flaw detection method for nondestructive inspection of the rotor disk 9 according to this embodiment will be described. The first probe 22 to which the first wedge member 22W is connected and the second probe 24 to which the second wedge member 24W is connected are supported by the support device 30. The support device 30 is supported by the rotor disk 9 so that the first wedge member 22W faces the disk surface 9A and the second wedge member 24W faces the inclined surface 9C.

  By the operation of the position adjustment mechanism 36, the positions of the first probe 22 and the first wedge member 22W in the radial direction are adjusted. When the ball roller 38 is in contact with the disk surface 9A of the rotor disk 9 and the driven roller 39 is in contact with the inclined surface 9C of the rotor disk 9, the surface of the first wedge member 22W and the disk surface 9A have a prescribed value (for example, 0). .5 [mm]), and the surface of the second wedge member 24W and the inclined surface 9C face each other with a predetermined gap.

  The contact medium is supplied from the supply device 66 to each of the gap between the surface of the first wedge member 22W and the disk surface 9A and the gap between the surface of the second wedge member 24W and the inclined surface 9C. The control device 26 operates the first probe 22 and the second probe 24, transmits an ultrasonic beam from the first probe 22, and transmits an ultrasonic beam from the first probe 22. In parallel with this, an ultrasonic beam is transmitted from the second probe 24. The ultrasonic beam transmitted from the first probe 22 is irradiated to the flaw detection site of the rotor disk 9 via the first wedge member 22W and the contact medium. Further, the ultrasonic beam transmitted from the second probe 24 is irradiated to the flaw detection site of the rotor disk 9 through the second wedge member 24W and the contact medium. The ultrasonic beam transmitted from the first probe 22 and the ultrasonic beam transmitted from the second probe 24 are simultaneously applied to the first corner 18A of the blade groove 17 which is a flaw detection site.

  The echo reflected by the first corner 18 </ b> A that is a flaw detection site is received by the first probe 22 and the second probe 24. In the present embodiment, the control device 26 detects the state of the crack 19 in the first corner 18 </ b> A based on the received signal received by the first probe 22 or the second probe 24.

  The drive roller 42 is operated by the operation of the motor 41 of the motor unit 40, and the support device 30 moves in the circumferential direction. In parallel with the movement of the support device 30 in the circumferential direction, the control device 26 transmits an ultrasonic beam from each of the first probe 22 and the second probe 24. Since the first probe 22 and the first wedge member 22W are supported by the support device 30 via the first gimbal mechanism 52, the first probe 22 and the first wedge member 22W can move following the shape of the disk surface 9A. Further, since the second probe 24 and the second wedge member 24W are supported by the support device 30 via the second gimbal mechanism 54, the second probe 24 and the second wedge member 24W can move following the shape of the inclined surface 9C.

  A magnet is provided in each of the first holding member 32 and the second holding member 34. It is suppressed that the first wedge member 22W and the disk surface 9A are separated from each other and the second wedge member 24W and the inclined surface 9C are separated from each other by the magnetic force of the magnet. The first wedge member 22W and the second wedge member 24W are movable in the circumferential direction while maintaining a gap with the surface of the rotor disk 9.

  As described above, with the first probe 22 provided on the disk surface 9A and the second probe 24 provided on the inclined surface 9C, the first probe 22 and the second probe 24 move in the circumferential direction. The example to do was demonstrated. When the first probe 22 and the second probe 24 move in the circumferential direction in a state where the first probe 22 is provided on the disk surface 9B and the second probe 24 is provided on the inclined surface 9D. Is the same. By providing the first probe 22 on the disk surface 9B and the second probe 24 on the inclined surface 9D, the state of the crack 19 in the second corner 18B is inspected.

[Action and effect]
As described above, according to this embodiment, in the T-route type rotor disk 9 in which the blade groove 17 is provided in the circumferential direction and the corner portion 18 is provided in the blade groove 17, it is more radial than the disk surface 9A. When the inclined surface 9C is provided on the outer side, the first probe 22 that is one of the first probe 22 and the second probe 24 that transmits an ultrasonic beam is provided on the disk surface 9A. In the state where the second probe 24, which is the other probe, is provided on the inclined surface 9C, the ultrasonic beam transmitted from the first probe 22 and the second probe 24 is transmitted through the blade groove 17. By irradiating the corner 18 and receiving echoes of at least one of the first probe 22 and the second probe 24, the crack 19 can be obtained without requiring a skill based on the received signals of the echoes. The presence or absence and the size of the crack 19 can be detected with high accuracy. Further, by moving the first probe 22 and the second probe 24 in the circumferential direction, the state of the crack 19 in the blade groove 17 can be inspected with high accuracy over a wide range.

  Further, the first probe 22 and the first wedge member 22W are supported by the first gimbal mechanism 52 so as to be movable, and the second probe 24 and the second wedge member 24W are supported by the second gimbal mechanism 54 so as to be movable. Thus, when the first wedge member 22W moves on the disk surface 9A and the second wedge member 24W moves on the inclined surface 9C, the first wedge member 22W follows the shape of the disk surface 9A, and the second wedge The member 24W can be made to follow the shape of the inclined surface 9C.

  Further, by providing the ball roller 38 and the driven roller 39 that are rotatable in contact with the surface of the rotor disk 9, the first wedge member 22W can smoothly move on the disk surface 9A, and the second wedge member 24W can smoothly move on the inclined surface 9C.

  In addition, by providing the position adjustment mechanism 36, it is possible to adjust the relative position between the detection area SA, which is the irradiation area of the ultrasonic beam, and the blade groove 17, thereby improving the inspection accuracy.

  Further, between the surface of the first wedge member 22W and the disk surface 9A facing the surface of the first wedge member 22W via a gap, and the surface of the second wedge member 24W and the surface of the second wedge member 24W A contact medium such as water or oil is supplied from the supply device 66 to each of the inclined surfaces 9C opposed to each other with a gap therebetween, and is transmitted from the first probe 22 to the first wedge member 22W. The ultrasonic beam emitted from the surface and the ultrasonic beam emitted from the second probe 24 and emitted from the surface of the second wedge member 24W are efficiently transmitted to the first corner portion 18A of the blade groove 17. Is done.

  In addition, since the magnet is provided in the main body member 31 that supports the first holding member 32 and the second holding member 34, the first wedge member 22W held by the first holding member 32 and the first The second wedge member 24 </ b> W held by the second holding member 34 can move the rotor disk 9 while maintaining a predetermined gap without leaving the surface of the rotor disk 9. Accordingly, the ultrasonic beam transmitted from the first probe 22 and the second probe 24 is stably irradiated onto the rotor disk 9.

[Second Specific Example of Ultrasonic Flaw Detector]
Next, a second specific example of the ultrasonic flaw detector 100 according to the present embodiment will be described. FIG. 18 is a perspective view showing a second specific example of the ultrasonic flaw detector 100 according to the present embodiment. FIG. 19 is a front view showing a second specific example of the ultrasonic flaw detector 100 according to the present embodiment. FIG. 20 is a longitudinal sectional view showing a second specific example of the ultrasonic flaw detector 100 according to the present embodiment. FIG. 21 is a side view showing a second specific example of the ultrasonic flaw detector 100 according to the present embodiment. In addition, it abbreviate | omits about the component and effect which overlap with a 1st specific example.

  As shown in FIGS. 18 to 21, in this embodiment, the first probe 22 is not only provided on the disk surface 9A and the second probe 24 is provided on the inclined surface 9C. A contact 28 is provided on the disk surface 9A. The third probe 28 is a phased array probe. By installing the third probe 28, it is possible to detect the surface of the rotor disk 9 or an internal crack.

  The support device 30 further includes a third holding member 56 that holds the third probe 28. The third holding member 56 is movable in the radial direction while being guided by the guide portion 36G. By adjusting the position of the third holding member 56, the position of the third probe 28 in the radial direction is adjusted. The support device 30 includes a position adjustment mechanism 36 that can adjust the position of the third probe 28 in the radial direction.

  As shown in FIG. 22, a scale indicator plate 62 is further installed on the third holding member 56. The scale indicator plate 62 is installed along the scale described above. The tip end of the scale indicator plate 62 is aligned with the tip end position of the third holding member 56. As a result, even when there is a gap between the scale and the third holding member 56, the tip position of the third holding member 56 is indicated by the scale indicator plate 62. Position adjustment can be performed easily.

1: rotating machine 2: turbine rotor 3: stator 4: shaft member 5: moving blade 6: casing 7: stationary blade 8: bearing 9: rotor disk 9A: disk surface 9B: disk surface 9C: inclined surface 9D: inclined surface 10 : Steam passage 11: Steam supply port 12: Steam discharge port 13: Blade root portion 14: Neck portion 15: Blade portion 16: Enlarged portion 17: Blade groove 18: Corner portion 18A: First corner portion 18B: Second corner portion 18C : Third corner 18D: Fourth corner 19: Crack 20: Housing 22: First probe 22A: First ultrasonic transducer 22W: First wedge member 24: Second probe 24A: Second super Sound transducer 24W: second wedge member 26: control device 28: third probe 30: support device 31: body member 31A: frame member 31B: frame member 32: first holding member 33: connecting member 34: second Protection Holding member 36: Position adjustment mechanism 36G: Guide portion 37: Protruding portion 38: Ball roller 38C: Support mechanism 39: Driven roller 39C: Support mechanism 40: Motor unit 41: Motor 42: Drive roller 43: Magnet 52: First gimbal Mechanism 54: Second gimbal mechanism 56: Third holding member 58: Bolt 59: Nut 62: Scale indicator plate 66: Supply device 70: Encoder unit 71: Encoder 72: Encoder roller 91: Thick part 92: Thick part 100 : Ultrasonic flaw detector

Claims (11)

An ultrasonic flaw detector for nondestructive inspection of a rotor disk of a turbine rotor having blade grooves,
The blade groove is provided in the circumferential direction of the rotating shaft of the turbine rotor,
The rotor disk has a disk surface facing an axial direction parallel to the rotation axis, and an inclined surface arranged radially outside the rotation axis with respect to the disk surface,
A first probe and a second probe that transmit an ultrasonic beam to a corner of the blade groove of the rotor disk;
The first probe and the second probe are arranged such that one of the first probe and the second probe is provided on the disk surface and the other probe is provided on the inclined surface. A support device for supporting the second probe;
A control device for detecting a crack state in the corner portion based on a reception signal of the second probe that has received an echo reflected by the corner portion;
With
The support device is an ultrasonic flaw detector that moves in the circumferential direction of the rotating shaft in a state where one of the probes is provided on the disk surface and the other probe is provided on the inclined surface. A first wedge member connected to one of the probes;
A second wedge member connected to the other probe,
The support device includes a first gimbal mechanism that movably supports one of the probes and the first wedge member, and a second gimbal that movably supports the other probe and the second wedge member. The ultrasonic flaw detector according to claim 1, further comprising a mechanism. The support device is
A first holding member for holding one of the probes and the first wedge member;
A second holding member for holding the other probe and the second wedge member;
A pair of frame members to which the first holding member and the second holding member are fixed and extending in a radial direction;
A driving roller that is provided on the frame member so as to face the disk surface and moves the support device;
Two driven rollers provided on the frame member so as to face the inclined surface;
The ultrasonic flaw detector according to claim 2, comprising:   The ultrasonic flaw detector according to claim 3, wherein a magnet is installed along the circumferential direction of the driving roller and the driven roller.   The ultrasonic flaw detector according to claim 3 or 4, wherein a magnet is installed along the length direction of the frame member on a surface facing the disk surface.   The shaft portion of the drive roller is fixed at a predetermined position so as not to swing in a direction away from the disk surface in the out-of-plane direction, and the shaft portion of the driven roller is separated from the inclined surface in the out-of-plane direction. The ultrasonic flaw detector according to any one of claims 3 to 5, which is fixed so as to be swingable with respect to a direction. The support device is
A first holding member for holding one of the probes and the first wedge member;
A second holding member for holding the other probe and the second wedge member;
A ball roller rotatable in contact with the rotor disk;
The ultrasonic flaw detector according to claim 2, comprising:   The said support apparatus has a position adjustment mechanism which can adjust the position of one said probe and said 1st wedge member in the radial direction of the said rotating shaft. Ultrasonic flaw detector.   The position adjusting mechanism includes a guide portion provided in a pair of frame members extending in a radial direction, a nut inserted into the guide portion, and a bolt screwed to the nut, and an opening of the guide portion The ultrasonic flaw detector according to claim 8, wherein a protruding portion protruding inward on the side is sandwiched between the nut and the bolt.   The supply device for supplying a contact medium to each of a gap between the surface of the first wedge member and the disk surface and a gap between the surface of the second wedge member and the inclined surface. The ultrasonic flaw detector as described in any one of Claims. An ultrasonic flaw detection method for nondestructive inspection of a rotor disk of a turbine rotor having blade grooves,
The blade groove is provided in the circumferential direction of the rotating shaft of the turbine rotor,
The rotor disk has a disk surface facing an axial direction parallel to the rotation axis, and an inclined surface arranged radially outside the rotation axis with respect to the disk surface,
Providing, on the disk surface, one of a first probe and a second probe that transmit an ultrasonic beam to a corner of the blade groove of the rotor disk;
Providing the other probe of the first probe and the second probe on the inclined surface;
Detecting a crack state at the corner based on a reception signal of the second probe that has received an echo reflected at the corner; and
With the one probe provided on the disk surface and the other probe provided on the inclined surface, the first probe and the second probe are moved in the circumferential direction of the rotating shaft. A moving step,
Including ultrasonic flaw detection methods.

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