JP6783176B2 - Ultrasonic flaw detector and ultrasonic flaw detection method - Google Patents

Description

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

The steam turbine has a turbine rotor and moving blades connected to the rotor disks of the turbine rotor. As the moving blades, a side entry type moving blade having a so-called Christmas tree-shaped wing root, a T-root type moving blade having a T-shaped wing root of the alphabet, a Curtis type moving blade, and the like are known. The rotor disk has a blade groove in which the blade root portion of the moving blade is arranged. By arranging the blade root portion of the moving blade in the blade groove of the rotor disk and fixing the rotor disk and the moving blade, the turbine rotor and the moving blade can rotate integrally.

Turbine rotors are operated under high temperature conditions. Therefore, after long-term use, stress corrosion cracking (SCC) may occur in the portion of the rotor disk on which repeated stress acts. In the case of a rotor disc to which a T-root type rotor blade is fixed, there is a high possibility that cracks will occur at the corners of the blade groove. Ultrasonic flaw detection inspection technology is known as a non-destructive inspection technology for inspecting the crack state of a T-root type rotor disk. Patent Document 1 discloses an ultrasonic flaw detector that inspects a turbine rotor by a phased array flaw detector method using a probe including a plurality of ultrasonic transducers. Patent Document 2 discloses an ultrasonic flaw detector that inspects a turbine rotor using a position monitoring probe and a flaw detector probe.

Japanese Unexamined Patent Publication No. 2009-244079 Japanese Unexamined Patent Publication No. 2013-68425

When the crack state of the T-root type rotor disk is inspected by the phased array flaw detection method, the size of the crack is evaluated from the difference between the echo reflected at the tip of the crack and the echo reflected at the corner of the blade groove. In order to detect the maximum value of the size of the crack based on the echo reflected at the tip of the crack, the inspector emits an ultrasonic beam from the probe while changing the angle and position of the probe. That is, the inspector performs the inspection while swinging and scanning the probe back and forth. The swing angle of the probe in the swing scan and the front-back scan distance of the probe in the front-back scan affect the detection accuracy of the crack size. When scanning the probe is performed manually, the skill of the inspector performing the inspection is required. In addition, when scanning the probe is performed manually, a large amount of inspection time is required.

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

A first aspect of the present invention is an ultrasonic flaw detector for non-destructive inspection of a rotor disk of a turbine rotor having a blade groove, wherein the blade groove is provided in the circumferential direction of the rotation axis of the turbine rotor, and the rotor is provided. The disk has a disk surface that faces an axial direction parallel to the rotation axis and an inclined surface that is arranged radially outside the rotation axis with respect to the disk surface, and has an angle of the blade groove of the rotor disk. A first probe and a second probe that emit an ultrasonic beam to a unit, and one of the first probe and the second probe are provided on the disk surface and the other. Of the 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 at the corner. A control device for detecting a crack state at the corner portion based on a received signal, and the support device includes one said probe provided on the disk surface and the other said probe on the inclined surface. Provided is an ultrasonic flaw detector that moves in the circumferential direction of the rotation axis in the provided state.

According to this configuration, in a T-root type rotor disk in which a blade groove is provided in the circumferential direction and a corner portion is provided in the blade groove, when an inclined surface is provided radially outside the disk surface, an ultrasonic beam is provided. The first probe and the second probe are provided in a state where 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. By irradiating the corner of the wing groove with the ultrasonic beam transmitted from the probe and receiving the echo with the second probe, skill is required based on the received signal of the second probe. The presence or absence of cracks and the dimensions of cracks 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.

In the first aspect, the support device 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 is one of the probes. It is preferable to have a first gimbal mechanism that movably supports the tentacle 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, whereby the first wedge is movably supported. 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 has 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. The member, the first holding member and the second holding member are fixed, and a pair of frame members extending in the radial direction are provided on the frame member so as to face the disk surface, and the support device is moved. It is preferable to have a driving roller to be operated and two driven rollers provided on the frame member so as to face the inclined surface.

In the first aspect, it is preferable that magnets are installed on the driving roller and the driven roller along the circumferential direction.

In the first aspect, it is preferable that a magnet is installed on the frame member along the length direction on the surface facing the disk surface.

In the first aspect, 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 the inclined surface. It is preferable that the vehicle is fixed so as to be swingable in a direction away from the plane.

In the first aspect, the support device has 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 disc surface, and the second wedge member can smoothly move on the inclined surface.

In the first aspect, it is preferable that the support device has a position adjusting mechanism capable of adjusting the positions of one of the probes and the first wedge member in the radial direction of the rotating shaft.

By providing the position adjusting mechanism, it is possible to adjust the relative position between the irradiation region of the ultrasonic beam and the blade groove, and the inspection accuracy can be improved.

In the first aspect, the position adjusting mechanism has a guide portion provided on a pair of frame members extending in the radial direction, a nut inserted into the guide portion, and a bolt screwed with the nut. It is preferable that the 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 for supplying a contact medium to each of the gap between the surface of the first wedge member and the disk surface and the gap between the surface of the second wedge member and the inclined surface is provided. preferable.

Inclinations facing each other between the surface of the first wedge member and the surface of the first wedge member and the disc surface facing each other through a gap, and between the surface of the second wedge member and the surface of the second wedge member and facing each other through a gap. By supplying a contact medium such as water or oil to each of the surfaces, an ultrasonic beam transmitted 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 non-destructive inspection of a rotor disk of a turbine rotor having a blade groove, wherein the blade groove is provided in the circumferential direction of the rotation axis of the turbine rotor, and the rotor is provided. The disk has a disk surface that faces an axial direction parallel to the rotation axis and an inclined surface that is arranged radially outside the rotation axis with respect to the disk surface, and has an angle of the blade groove of the rotor disk. A step of providing a probe of either a first probe or a second probe that emits an ultrasonic beam to a unit on the disk surface, and a step of providing the first probe and the second probe of the first probe and the second probe. One of the steps of providing the other probe on the inclined surface and the step of detecting the crack state at the corner based on the reception signal of the second probe that received the echo reflected at the corner. The first probe is provided by a support device that supports the first probe and the second probe in a state where the probe is provided on the disk surface and the other probe is provided on the inclined surface . Provided is an ultrasonic flaw detection method including a step of moving the probe and the second probe in the circumferential direction of the rotation axis.

According to this configuration, in a T-root type rotor disk in which a blade groove is provided in the circumferential direction and a corner portion is provided in the blade groove, when an inclined surface is provided radially outside the disk surface, an ultrasonic beam is provided. The first probe and the second probe are provided in a state where 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. By irradiating the corner of the wing groove with the ultrasonic beam transmitted from the probe and receiving the echo with the second probe, skill is required based on the received signal of the second probe. The presence or absence of cracks and the dimensions of cracks can be detected with high accuracy. Further, the supporting device, by Rukoto moving the first probe and second probe in the circumferential direction, it is possible to inspect the crack state of the blade groove in a wide range with high accuracy.

According to the present invention, there is provided an ultrasonic flaw detection device and an ultrasonic flaw detection method for a turbine rotor that can perform non-destructive inspection in a short time without requiring skill.

FIG. 1 is a diagram schematically showing an example of a rotary machine according to the present embodiment. FIG. 2 is a perspective view showing a part of the moving blade and the rotor disk according to the present embodiment. FIG. 3 is a cross-sectional view showing a part of the moving 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 view showing an example of the ultrasonic flaw detector according to the present 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 vertical cross-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 vertical cross-sectional view showing a second specific example of the ultrasonic flaw detector according to the present 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 components in the embodiments described below can be combined as appropriate. In addition, some components may not be used.

[Rotating machine]
FIG. 1 is a diagram schematically showing an example of a rotary 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 rotary machine 1 may be a gas turbine or a compressor.

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

In the following description, the direction parallel to the rotation axis AX of the turbine rotor 2 is appropriately referred to as the width direction, and the radiation direction of the turbine rotor 2 with respect to the rotation axis AX is appropriately referred to as the radial direction, and the rotation of the turbine rotor 2 is performed. The direction of rotation about the axis AX is appropriately referred to as the circumferential direction. Further, the position far from or away from the rotation axis AX in the radial direction is appropriately referred to as the radial outside, and the position close to or approaching the rotation axis AX in the radial direction is appropriately referred to as the radial inside.

The turbine rotor 2 is rotatably supported by the casing 6 via a bearing 8. At least a portion of the turbine rotor 2 is located inside the casing 6. The rotor 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. Further, 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. Further, 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 a plurality of stages so as to be arranged between the moving blades 5 in the axial direction.

The casing 6 has a steam passage 10 in which the moving blade 5 and the stationary blade 7 are arranged, a steam supply port 11 for supplying steam to the steam passage 10, and a steam discharge port 12 for discharging steam from the steam passage 10. The steam supplied from the steam supply port 11 flows through the steam passage 10 while contacting the moving blades 5 and the stationary blades 7. When the steam comes into contact with the moving blades 5, the turbine rotor 2 rotates about the rotation shaft AX. When the turbine rotor 2 rotates, the generator connected to the shaft member 4 is driven. The steam flowing through the steam passage 10 is discharged from the steam discharge port 12.

[Roblade and rotor disk]
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 disc 9. In the present embodiment, the moving blade 5 is a T-root type moving blade having a T-shaped wing root portion 13 of the alphabet. A plurality of moving blades 5 are provided in the circumferential direction. The blade root portion 13 is arranged in the blade groove 17 provided in the rotor disc 9. The blade groove 17 is provided in the circumferential direction.

The wing root portion 13 has a neck portion 14 and an enlarged portion 16 which is arranged radially inside the neck portion 14 and whose axial dimension is larger than that of the neck portion 14.

The rotor disc 9 has a blade groove 17 in which the blade root portion 13 is arranged. The wing groove 17 has a plurality of corner portions 18. As shown in FIG. 3, in the present embodiment, the corner portion 18 includes a first corner portion 18A, a second corner portion 18B, a third corner portion 18C, and a fourth corner portion 18D. The first corner portion 18A and the second corner portion 18B are arranged in the axial direction. The third corner portion 18C and the fourth corner portion 18D are arranged in the axial direction. The first corner portion 18A is arranged radially outside the third corner portion 18C. The second corner portion 18B is arranged radially outside the fourth corner portion 18D.

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

In this embodiment, the rotor disc 9 supports a T-root type rotor blade. As shown in FIG. 3, the rotor disk 9 has a disk surface 9A facing one side in the axial direction, a disk surface 9B facing the other side in the axial direction, and a disk surface 9A arranged radially outside the disk surface 9A. It has an inclined surface 9C connected to the disk surface 9C and an inclined surface 9D arranged radially outside the disk surface 9B and connected to the disk surface 9B.

In the present embodiment, the disk surface 9A and the disk surface 9B are flat surfaces substantially orthogonal to the rotation axis AX, respectively. The inclined surface 9C and the inclined surface 9D are respectively inclined toward the outer side in the radial direction so as to approach the center line ML.

The center line ML is a virtual line passing through the center of the rotor disk 9 in the axial direction among the radiation of the rotation axis AX.

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

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

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

[Outline of ultrasonic flaw detector: 1st Example]
Next, the first embodiment 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 emits an ultrasonic beam to the first corner portion 18A of the blade groove 17 of the rotor disk 9, and a first probe 22 of the blade groove 17. It has a second probe 24 that emits an ultrasonic beam to one corner portion 18A, and a control device 26 that controls the first probe 22 and the second probe 24.

The first probe 22 and the second probe 24 are arranged so as to face each other with the first corner portion 18A, which 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, the first corner portion 18A, which is a flaw detection site, is arranged between the first probe 22 and the second probe 24. Further, 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 apply an exciting voltage to each of the plurality of ultrasonic vibrators of the first probe 22 to transmit an ultrasonic beam from the first probe 22. Similarly, the control device 26 can apply an exciting voltage to each of the plurality of ultrasonic vibrators of the second probe 24 to emit an ultrasonic beam from the second probe 24.

The first probe 22 emits an ultrasonic beam. The ultrasonic beam transmitted from the first probe 22 irradiates the flaw detection portion of the rotor disk 9. The control device 26 controls the exciting voltage applied to the plurality of ultrasonic vibrators of the first probe 22 to scan 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 region SA. The detection region SA is a region through which the ultrasonic beam transmitted from the first probe 22 passes.

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

The second probe 24 receives the echo reflected at the flaw detection portion when the flaw detection portion of the rotor disk 9 is irradiated with the ultrasonic beam. That is, in the present embodiment, the first corner portion 18A, which is the flaw detection site of the rotor disk 9, is irradiated with the ultrasonic beam from both the first probe 22 and the second probe 24. The control device 26 simultaneously launches the ultrasonic beam from the first probe 22 to the first corner 18A and the ultrasonic beam from the second probe 24 to the first corner 18A. .. The echo generated in the first corner portion 18A by the irradiation of 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 portion 18A based on the received signal of the second probe 24 that has received the echo reflected by the first corner portion 18A. The control device 26 detects, for example, the size of the crack 19 based on the received signal of the second probe 24 that has received the echo.

The echo generated in the first corner portion 18A by being irradiated with the ultrasonic beam may be received by the first probe 22. The control device 26 may detect the state of the crack 19 in the first corner portion 18A based on the received signal of the first probe 22 that has received the echo reflected by the first corner portion 18A.

As described above, in the present embodiment, the first probe 22 and the second probe 24 composed of the phased array probe are arranged to face each other, and the first probe 22 and the second probe 24 are arranged. An ultrasonic beam is transmitted from both the first probe 22 and the second probe 24 to the first corner portion 18A in a state where the first corner portion 18A, which is a flaw detection site, is arranged between the first corner portions 18A. At least one of the probe 22 and the second probe 24 receives the echo. The control device 26 detects the state of the crack 19 based on the received signal of at least one of the first probe 22 and the second probe 24 that have received the echo. As a result, the relative position between the first probe 22 and the second probe 24 can be adjusted with high accuracy, the installation position and installation angle of the first probe 22 can be adjusted with high accuracy, and the second 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 positions of the first probe 22 and the second probe 24 in the radial direction change. As a result, 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 portion 18 can be detected over a wide area in the small detection region SA.

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

[Outline of ultrasonic flaw detector: Second Example]
Next, a second embodiment 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 with the flaw detection portion of the first corner portion 18A in between. 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 portion of the first corner portion 18A is arranged between the first probe 22 and the second probe 24. Further, 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, which are phased array probes, are arranged so as to face each other, and are located between the first probe 22 and the second probe 24. With the flaw detection site of the first corner 18A arranged, 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 22 and the second probe 24 At least one of the probes 24 receives the echo. The control device 26 detects the state of the crack 19 based on the received signal of at least one of the first probe 22 and the second probe 24 that have received the echo. Also in the second embodiment, the relative positions of the first probe 22 and the second probe 24 are adjusted with high accuracy, and the installation position and the installation angle of the first probe 22 are adjusted with high accuracy. Alternatively, the dimensions of the crack 19 can be detected without adjusting the installation position and 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 positions of the first probe 22 and the second probe 24 in the circumferential direction change. As a result, 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 portion 18 can be detected over a wide area in a small detection region SA.

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

[Outline of ultrasonic flaw detector: Third Example]
Next, a third embodiment 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, the first ultrasonic vibrator 22A functioning as the first probe 22 and the second ultrasonic vibrator 24A functioning as the second probe 24 are supported by one housing 20. , Is integrated. The first ultrasonic vibrator 22A and the second ultrasonic vibrator 24A are arranged so as to face each other with the flaw detection portion of the first corner portion 18A interposed therebetween. In the third embodiment, the first ultrasonic vibrator 22A and the second ultrasonic vibrator 24A are arranged in the radial direction. In the radial direction, the first ultrasonic vibrator 22A and the second ultrasonic vibrator 24A face each other. In the radial direction, the flaw detection portion of the first corner portion 18A is arranged between the first ultrasonic vibrator 22A and the second ultrasonic vibrator 24A. Further, in the third embodiment, both the first ultrasonic vibrator 22A and the second ultrasonic vibrator 24A are arranged on the disk surface 9A. The first ultrasonic vibrator 22A and the second ultrasonic vibrator 24A may be arranged in the circumferential direction.

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

[Outline of ultrasonic flaw detector: Fourth Example]
Next, a fourth embodiment of the outline of the ultrasonic flaw detector 100 according to the present embodiment will be described. 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 with the flaw detection portion of the first corner portion 18A in between. 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 portion of the first corner portion 18A is arranged between the first probe 22 and the second probe 24. Further, 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, which are phased array probes, are arranged so as to face each other, and are located between the first probe 22 and the second probe 24. With the flaw detection site of the first corner 18A arranged, 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 22 and the second probe 24 are emitted. At least one of the probes 24 receives the echo. The control device 26 detects the state of the crack 19 based on the received signal of at least one of the first probe 22 and the second probe 24 that have received the echo. Also in the fourth embodiment, the relative positions of the first probe 22 and the second probe 24 are adjusted with high accuracy, and the installation position and the installation angle of the first probe 22 are adjusted with high accuracy. Alternatively, the dimensions of the crack 19 can be detected without adjusting the installation position and installation angle of the second probe 24 with high accuracy.

Also in the fourth embodiment, the first probe 22 and the second probe 24 can move 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 carried out, and the first probe 22 and the second probe 24 are moved in the radial direction. 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 portion 18 can be detected over a wide area in the small detection region SA.

Further, when the first probe 22 and the second probe 24 move together in the circumferential direction, the blade groove 17 arranged in the circumferential direction can be detected 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 view showing 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 vertical cross-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 so that the first probe 22 is provided on the disk surface 9A and the second probe 24 is provided on the inclined surface 9C. A control device that detects the state of the crack 19 in the corner portion 18 based on the received signal of the support device 30 that supports the corner portion 18 and the second probe 24 that has received the echo reflected by the corner portion 18 (first corner portion 18A). It includes 26.

Further, 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 disc 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 has the first probe 22 and the beam transmitted from the second probe 24 so that the beam transmitted from the first probe 22 and the beam transmitted from the second probe 24 irradiate the flaw detection portion 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, and the first wedge member 22W. 2 The probe 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 second holding member 34. It has one holding member 32 and a main body member 31 that supports the second holding member 34.

Further, the support device 30 can adjust the positions of the first probe 22 and the first wedge member 22W in the radial direction, or the positions 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 has a pair of frame members 31A and 31B extending in the radial direction, and a connecting member 33 for connecting the frame member 31A and the frame member 31B.

The position adjusting mechanism 36 has a guide portion 36G provided on the frame members 31A and 31B. The first holding member 32 and the second holding member 34 can move 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 arranged 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 positions 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.

The position adjusting mechanism 36 has a bolt 58 and a nut 59 as shown in FIG. Further, the guide portion 36G provided on the frame members 31A and 31B has a protruding portion 37 protruding inward on 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 arranged inside the groove of the guide portion 36G, and by tightening the bolt 58, the nut 59 is pulled up toward 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 between 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 from the guide portion 36G unless it comes off from the nut 59.

Further, the support device 30 includes a ball roller 38 and a driven roller 39 that movably support the main body member 31, a motor unit 40 having a motor 41 and a drive roller 42 driven by the motor 41, and an encoder 71 and an encoder roller 72. It has an encoder unit 70 having the above. 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 the support mechanism 38C. The ball roller 38 travels on the disc surface 9A in the circumferential direction. The ball roller 38 is made of, for example, a non-magnetic material. By adopting the ball roller 38 instead of the roller that rotates about only one axis, it is possible to easily correspond to the rotor discs 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 the 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 tilted surface 9C and the curvature (shape in the circumferential direction) of the rotor disk 9 by the swing mechanism. Further, it is desirable that the shaft portion of the encoder roller 72 is swingably fixed by a swing mechanism in a direction away from the disc surface 9A of the rotor disc 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.

The driven roller 39 has a disk shape and rotates about 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 inside the groove along the circumferential direction. The magnet is, for example, neodymium, and is installed on the driven roller 39 so as to be separated from the inclined surface 9C of the rotor disk 9 and not in contact with the magnet. As a result, when the ultrasonic flaw detector 100 is moved, the ultrasonic flaw detector 100 is less likely to separate 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 fixing angle of the driven roller 39. By changing the fixed angle of the driven roller 39 by the adjusting mechanism, it is possible to correspond to the rotor disc 9 having a different radius and the rotor disc 9 having a different tilt angle of the tilted surface 9C.

The motor unit 40 has a motor 41 and a drive roller 42 that is rotated by the power generated by the motor 41. The drive roller 42 travels on the disc surface 9A in the circumferential direction. The drive roller 42 is rotated by the operation of the motor 41, so that 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 motor unit 40 adjusts the relative positions of the first probe 22 and the first wedge member 22W and the rotor disc 9 in the circumferential direction, and the second probe 24 and the second wedge member 24W and the rotor disc in the circumferential direction are adjusted. The relative position with 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 about 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 inside the groove along the circumferential direction. The magnet is, for example, neodymium, and is installed on the drive roller 42 so as to be separated from the disk surface 9A of the rotor disk 9 and not in contact with the magnet. As a result, when the ultrasonic flaw detector 100 is moved, the ultrasonic flaw detector 100 is less likely to separate 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 drive roller 42 is fixed at a predetermined position so as not to swing in the direction away from the disc surface 9A of the rotor disk 9 in the out-of-plane direction. As a result, the drive roller 42 can be prevented from idling.

Magnets are installed in the two driven rollers 39 and the driving roller 42 along the circumferential direction as described above, and the ultrasonic flaw detector 100 is stably supported by the rotor disk 9 at three points. Will be done. When the drive roller 42 is rotated by the operation of the motor 41, the drive roller 42 is in a straight motion, but the ultrasonic flaw detector 100 is a rotor disk 9 due to the three-point support by the two driven rollers 39 and the drive roller 42. It is possible to reliably rotate and run along the circumferential direction of.

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 amount of movement of the main body member 31 in the circumferential direction based on the amount of rotation of the encoder roller 72.

The encoder roller 72 of the encoder unit 70 has a disk shape and rotates about 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 inside the groove along the circumferential direction. The magnet is, for example, neodymium, and is installed on the encoder roller 72 so as to be separated from the disk surface 9A of the rotor disk 9 and not in contact with the magnet. As a result, when the ultrasonic flaw detector 100 is moved, the ultrasonic flaw detector 100 is less likely to separate 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 swingably fixed 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 drive roller 42 described above can be easily realized. Further, 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 be reliably rotated and traveled along the circumferential direction of the rotor disk 9.

The support device 30 has a ball roller 38 and a driven roller 39 that can rotate in contact with the rotor disc 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 disc surface 9A come into contact with each other, and the driven roller 39 and the inclined surface 9C come into contact with each other between the disc surface 9A and the surface of the first wedge member 22W facing the disc surface 9A. A gap is formed in the inclined surface 9C, and 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 movably supports the first gimbal mechanism 52 that movably supports the first probe 22 and the first wedge member 22W, and the second probe 24 and the second wedge member 24W. It has 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 movably supports the first probe 22 and the first wedge member 22W. 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 about 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 is movable relative to the main body member 31. The second gimbal mechanism 54 rotatably supports the second probe 24 and the second wedge member 24W about two axes including at least a second roll axis and a second pitch axis orthogonal to the second roll axis. ..

Further, the first holding member 32 and the second holding member 34 each have a magnet. The magnet is provided on the first holding member 32 so as to face the disc surface 9A. Further, the magnet is provided on the second holding member 34 so as to face the inclined surface 9C.

Each of the frame members 31A and 31B has a magnet 43. The magnet 43 is provided so as to face the disc surface 9A along the length direction of the frame members 31A and 31B. The magnet 43 is separated from the disk surface 9A of the rotor disk 9 and installed on the frame members 31A and 31B so as not to come into contact with each other. This makes it difficult for the ultrasonic flaw detector 100 to separate from the disk surface 9A in the out-of-plane direction when the ultrasonic flaw detector 100 moves, while reducing the resistance when the ultrasonic flaw detector 100 moves.

A number that functions as a scale may be written 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. As a result, the positions of the first probe 22 and the second probe 24 can be easily adjusted.

Further, as shown in FIG. 12, the support device 30 provides a contact medium in 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. A supply device 66 for supplying is provided. The contact medium contains water or oil.

Next, an ultrasonic flaw detection method for non-destructive inspection of the rotor disk 9 according to the present 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 disc surface 9A and the second wedge member 24W faces the inclined surface 9C.

By operating the position adjusting mechanism 36, the positions of the first probe 22 and the first wedge member 22W in the radial direction are adjusted. The ball roller 38 comes into contact with the disc surface 9A of the rotor disc 9, and the driven roller 39 comes into contact with the inclined surface 9C of the rotor disc 9, so that the surface of the first wedge member 22W and the disc surface 9A have specified values (for example, 0). The surface of the second wedge member 24W and the inclined surface 9C face each other through a gap of .5 [mm]), and the surface of the second wedge member 24W and the inclined surface 9C face each other through a gap of a specified value.

The contact medium is supplied from the supply device 66 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. The control device 26 operates the first probe 22 and the second probe 24 to emit an ultrasonic beam from the first probe 22 and emit an ultrasonic beam from the first probe 22. In parallel with this, an ultrasonic beam is emitted from the second probe 24. The ultrasonic beam transmitted from the first probe 22 is applied to the flaw detection portion 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 portion of the rotor disk 9 via 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 irradiated to the first corner portion 18A of the blade groove 17, which is a flaw detection site.

The echo reflected by the first corner portion 18A, which is the 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 portion 18A 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. The control device 26 emits an ultrasonic beam from each of the first probe 22 and the second probe 24 in parallel with the movement of the support device 30 in the circumferential direction. Since the first probe 22 and the first wedge member 22W are supported by the support device 30 via the first gimbal mechanism 52, they 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, they can move following the shape of the inclined surface 9C.

Further, magnets are provided on each of the first holding member 32 and the second holding member 34. The magnetic force of the magnet prevents the first wedge member 22W and the disc surface 9A from being separated from each other, or the second wedge member 24W and the inclined surface 9C from being separated from each other. The first wedge member 22W and the second wedge member 24W can move in the circumferential direction while maintaining a gap with the surface of the rotor disk 9.

As described above, 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 9A and the second probe 24 is provided on the inclined surface 9C. An example of doing so was explained. When the first probe 22 and the second probe 24 move in the circumferential direction while 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 portion 18B is inspected.

[Action and effect]
As described above, according to the present embodiment, in the T-root 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, the radial direction is larger than the disk surface 9A. When the inclined surface 9C is provided on the outside, the first probe 22 which is one of the first probe 22 and the second probe 24 that emits an ultrasonic beam is provided on the disk surface 9A. In a 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 to the blade groove 17. By irradiating the corner portion 18 and receiving an echo at at least one of the first probe 22 and the second probe 24, the crack 19 is based on the received signal of the echo and does not require skill. The presence or absence of the crack 19 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 movably supported by the first gimbal mechanism 52, and the second probe 24 and the second wedge member 24W are movably supported by the second gimbal mechanism 54. As a result, when the first wedge member 22W moves on the disc surface 9A and the second wedge member 24W moves on the inclined surface 9C, the first wedge member 22W follows the shape of the disc 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 can rotate in contact with the surface of the rotor disc 9, the first wedge member 22W can smoothly move on the disc surface 9A, and the second wedge member 24W can move smoothly on the inclined surface 9C.

Further, by providing the position adjusting mechanism 36, it is possible to adjust the relative position between the detection region SA, which is the irradiation region of the ultrasonic beam, and the blade groove 17, and the inspection accuracy can be improved.

Further, between the surface of the first wedge member 22W and the surface of the first wedge member 22W and the disk surface 9A facing each other through a gap, and between 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 facing each other through the gap, so that the contact medium is transmitted from the first probe 22 and is transmitted from the first wedge member 22W. The ultrasonic beam emitted from the surface and the ultrasonic beam emitted from the surface of the second wedge member 24W and emitted from the surface of the second wedge member 24 are efficiently transmitted to the first corner portion 18A of the blade groove 17. Will be done.

Further, since the main body member 31 that supports the first holding member 32 and the second holding member 34 is provided with a magnet, the first wedge member 22W and the first wedge member 22W held by the first holding member 32 by the magnetic force of the magnet. 2 The second wedge member 24W held by the holding member 34 can move the rotor disc 9 without leaving the surface of the rotor disc 9 while maintaining a gap of a specified value. As a result, the ultrasonic beams transmitted from the first probe 22 and the second probe 24 are stably irradiated to 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 vertical cross-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. The components and effects that overlap with the first specific example will be omitted.

As shown in FIGS. 18 to 21, in the present embodiment, not only the first probe 22 is provided on the disk surface 9A and the second probe 24 is provided on the inclined surface 9C, but also the third probe is provided. A tentacle 28 is provided on the disc surface 9A. The third probe 28 is a phased array probe. By installing the third probe 28, it is possible to detect cracks on the surface and inside of the rotor disk 9.

The support device 30 further includes a third holding member 56 that holds the third probe 28. The third holding member 56 can move 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 has a position adjusting mechanism 36 capable of adjusting 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 of the scale indicator plate 62 is aligned with the tip 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 described above, the tip position of the third holding member 56 is indicated by the scale indicator plate 62, so that the third probe 28 The position can be easily adjusted.

1: Rotating machine 2: Turbine rotor 3: Stator 4: Shaft member 5: Moving blade 6: Casing 7: Static 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 part 14: Neck part 15: Blade part 16: Expansion part 17: Blade groove 18: Corner part 18A: First corner part 18B: Second corner part 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 oscillator 24W: Second wedge member 26: Control device 28: Third probe 30: Support device 31: Main body member 31A: Frame member 31B: Frame member 32: First holding member 33: Connecting member 34: Second Holding member 36: Position adjusting mechanism 36G: Guide part 37: Protruding part 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 that non-destructively inspects the rotor discs of turbine rotors with blade grooves.
The blade groove is provided in the circumferential direction of the rotation shaft of the turbine rotor.
The rotor disk has a disk surface that faces an axial direction parallel to the rotation axis, and an inclined surface that is arranged radially outside the rotation axis with respect to the disk surface.
A first probe and a second probe that emit an ultrasonic beam to the corner of the blade groove of the rotor disk, and
The first probe and the first probe and the second probe so that one of the first probe and the second probe is provided on the disc surface and the other probe is provided on the inclined surface. A support device that supports the second probe and
A control device that detects the crack state at the corner based on the received signal of the second probe that received the echo reflected at the corner.
With
The support device is an ultrasonic flaw detector that moves in the circumferential direction of the rotation axis with one of the probes provided on the disk surface and the other probe provided on the inclined surface. A first wedge member connected to one of the probes,
A second wedge member connected to the other probe is provided.
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 that holds the probe and the first wedge member,
A second holding member that holds 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 extend in the radial direction,
A drive roller provided on the frame member so as to face the disk surface and move the support device, and
Two driven rollers provided on the frame member so as to face the inclined surface, and
The ultrasonic flaw detector according to claim 2. The ultrasonic flaw detector according to claim 3, wherein magnets are installed on the driving roller and the driven roller along the circumferential direction. The ultrasonic flaw detector according to claim 3 or 4, wherein a magnet is installed on the frame member on a surface facing the disk surface along the length direction. 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 that holds the probe and the first wedge member,
A second holding member that holds the other probe and the second wedge member,
A ball roller that can rotate in contact with the rotor disc,
The ultrasonic flaw detector according to claim 2. The support device according to any one of claims 2 to 7, wherein the support device has a position adjusting mechanism capable of adjusting the positions of one of the probes and the first wedge member in the radial direction of the rotating shaft. Ultrasonic flaw detector. The position adjusting mechanism has a guide portion provided on a pair of frame members extending in the radial direction, a nut inserted into the guide portion, and a bolt screwed with the nut, and the opening of the guide portion. The ultrasonic flaw detector according to claim 8, wherein the protruding portion protruding inward on the side is sandwiched between the nut and the bolt. Claims 2 to 9 include a supply device for supplying a contact medium to each of the gap between the surface of the first wedge member and the disk surface and the gap between the surface of the second wedge member and the inclined surface. The ultrasonic flaw detector according to any one item. An ultrasonic flaw detection method that non-destructively inspects the rotor disc of a turbine rotor with a blade groove.
The blade groove is provided in the circumferential direction of the rotation shaft of the turbine rotor.
The rotor disk has a disk surface that faces an axial direction parallel to the rotation axis, and an inclined surface that is arranged radially outside the rotation axis with respect to the disk surface.
A step of providing a probe of either a first probe or a second probe that emits an ultrasonic beam at a corner of the blade groove of the rotor disc on the disc surface.
A step of providing the first probe and the other probe of the second probe on the inclined surface, and
A step of detecting the crack state at the corner based on the received signal of the second probe that received the echo reflected at the corner, and
The support device that supports the first probe and the second probe in a state where one of the probes is provided on the disk surface and the other probe is provided on the inclined surface is used. A step of moving the first probe and the second probe in the circumferential direction of the rotation axis, and
Ultrasonic flaw detection methods including.

Images