JP2001221780A - Method and device of ultrasonic inspection of rotor inspection object - Google Patents

Abstract

PROBLEM TO BE SOLVED: To measure, effectively in a short time, an internal defect or a surface flaw generated in the diameter direction or the like by an ultrasonic inspection method relative to the side part of a rotor inspection object. SOLUTION: A probe 16 is arranged outside the side part of the rotor inspection object 11 or the like, and as relative position relation between the inspection object and the probe, the probe is moved in the circumferential direction of the inspection object, and simultaneously moved in the axial direction thereof, to thereby execute flaw detection inside the peripheral side part of the inspection object or the like. While the probe makes one revolution in the circumferential direction on the side part, the probe is simultaneously adjusted to make a round trip in the axial direction, and this operation is repeated in a prescribed condition by setting an offset quantity on the inspection starting position. The inspection is executed so that plural spiral inspection loci 31 are drawn at substantially equal spaces on the whole surface of a development of the side part. Hereby, a defect 32 in the diameter direction or in the circumferential direction is detected.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and an apparatus for ultrasonic inspection of a rotating object to be inspected, and more particularly to a method of inspecting a cylindrical side surface of an automobile engine cylinder or the like to shorten the inspection time for a radial defect. The present invention relates to a method and an apparatus for ultrasonic inspection that improve inspection performance.

[0002]

2. Description of the Related Art An example of a conventional apparatus is the "ultrasonic flaw detection method" (Nikkan Kogyo Shimbun, new edition revised on July 30, 1974 (6 new edition revised on June 1, 1984), Japan Society for the Promotion of Science) Ed., 19th Committee of the Japan Steelmaking Association), p. 539, (iii) Bonding test. The flaw detection apparatus described in this document is an apparatus for inspecting a uranium core-aluminum coating joint. The fuel rod to be inspected has a columnar appearance. The fuel rods are arranged horizontally in the water in the water tank with their axes horizontal. Both ends of the fuel rod are rotatably supported in the water tank, and are rotated about its axis by a motor. A point focus probe is arranged so as to face the side surface with respect to the fuel rod. Flaw detection of a fuel rod by a probe is performed by moving the probe in the axial direction of the fuel rod while rotating the fuel rod with a motor. In this flaw detection, the quality of the joint between the core material of the fuel rod and the cladding tube is inspected for good or bad. The fuel rod has an outer diameter of 50 to 100 m.
m, the length is 700 to 790 mm.

In the above-mentioned conventional apparatus, the probe is usually moved in synchronization with this rotation while rotating the fuel rod around its axis. Therefore, a spiral inspection trajectory is drawn to obtain flaw detection data, and flaw detection data is obtained. An inspection is performed. According to the above document, the rotational speed of the fuel rod is 250 to 300 revolutions / minute, and the reciprocating speed of the probe is 3.55 mm / sec.

[0004]

According to a conventional flaw detection method for a test object having the form of a rotating body, flaw detection data is obtained by drawing a spiral test trajectory to perform a test. In this case,
Since the probe is simply moving with respect to the rotating inspection object without giving a special mechanism, the spiral inspection trajectory finally obtained is only a single continuous inspection trajectory. Absent. In addition, since the flaw detection operation is performed by setting the spiral pitch of the spiral inspection trajectory to be relatively small, the conventional flaw detection apparatus requires a long time for the inspection.

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned problem, and a method of performing ultrasonic flaw detection from a side portion by reciprocating a probe while rotating an object to be inspected in the form of a rotating body, It is an object of the present invention to provide a method and an apparatus for ultrasonic inspection of a rotating body inspection object capable of shortening an inspection time and efficiently measuring an internal defect or a surface flaw generated in a radial direction or the like in a short time.

[0006]

The ultrasonic flaw detection method for a rotating object to be inspected according to the present invention comprises the following procedure in order to achieve the above object.

An ultrasonic flaw detection method according to the present invention (corresponding to claim 1): The object to be inspected has a form of a rotating body. For example, it has a cylindrical or cylindrical shape. The probe is usually disposed at a position outside the side surface forming the peripheral portion of the cylinder or cylinder in the inspection object, facing the surface of the side surface from the outside. When the object to be inspected has a cylindrical shape, the probe may be arranged to face the inner side surface.
The test object and the probe are maintained in a relative positional relationship such that the probe is moved in the circumferential direction of the test object and at the same time in the axial direction. For example, the test object is rotated around its axis, and the probe is moved in the axial direction. In this manner, the inside of the side portion of the inspection object and the like is detected by the probe. Further, as a characteristic configuration, when the probe makes one rotation on the side surface portion, the probe is reciprocated one time in the axial direction at the same time, and this flaw detection operation is repeated while setting a shift amount (offset amount). In this way, a plurality of spiral inspection trajectories are drawn substantially at equal intervals over the developed view of the side surface portion of the inspection object, and defect information is obtained based on the plurality of inspection trajectories. In order to draw a plurality of spiral inspection trajectories at substantially equal intervals over the developed view of the side surface portion of the inspection object, a predetermined shift amount is set each time the reciprocating operation is performed. Is required.

[0008] As a specific configuration, preferably, the object to be inspected is arranged on a rotary table driven by a motor, and the object to be inspected is rotated around its axis by the rotary table. The probe arranged as described above with respect to the object to be inspected is moved one reciprocation in the axial direction of the object to be inspected by the driving robot, and this is repeated according to predetermined conditions described later. For the driving robot, for example, a commercially available two-axis orthogonal drive mechanism that enables movement in two-axis directions (X-axis direction and Z-axis direction) is used. Synchronization is established between the rotating operation of the inspection object and the reciprocating operation of the probe. These operations need only be able to obtain the plurality of inspection trajectories described above, and can be set arbitrarily.

As described above, a plurality of spiral inspection lines are obtained by forming a line of the inspection trajectory in a spiral state, and setting a constant shift amount, that is, offsetting each time the spiral trajectory is drawn. Defects or the like that occur in the radial or circumferential direction can be efficiently inspected in a short time.

In the above ultrasonic flaw detection method, preferably, when the probe starts one rotation, the inspection start position is shifted by a predetermined amount (offset amount) in the circumferential direction by a plurality of inspection trajectories. (Corresponding to claim 2).

In the above-described ultrasonic flaw detection method, preferably, a plurality of inspection trajectories are drawn by shifting the inspection start position by a predetermined amount in the axial direction when the probe starts one rotation. Corresponds to item 3).

Further, the ultrasonic flaw detector for a rotating object to be inspected according to the present invention is configured as follows to achieve the above object.

An ultrasonic flaw detector according to the present invention (corresponding to claim 4): An ultrasonic flaw detector that flaw-detects a side surface of an inspection object based on the premise described in the above ultrasonic flaw detection method. . As a characteristic configuration, furthermore, a rotation drive mechanism (a mechanism including a rotary table, a motor, a device for rotating the inspection object, etc.) for rotating the inspection object arranged in the water tank around its axis, and an arm with the probe A reciprocating drive mechanism (a mechanism consisting of a driving robot, a robot controller, etc.) that moves the probe close to the side surface of the object to be inspected and reciprocates in the axial direction, synchronized with one rotation of the probe And a control means (sequence controller) for controlling the rotary drive mechanism and the reciprocal drive mechanism so that the flaw detection operation is repeated while setting the shift amount. With the above configuration, the above-described ultrasonic flaw detection method is performed.

In the ultrasonic flaw detector, preferably, the control means controls the test start position to be shifted by a predetermined amount in the circumferential direction when the probe starts one rotation. (Response), or control is performed such that the inspection start position is shifted by a predetermined amount in the axial direction when the probe starts one rotation (corresponding to claim 6).

[0015]

Preferred embodiments of the present invention will be described below with reference to the accompanying drawings.

FIG. 1 shows the overall configuration of an apparatus to which the present invention is applied. The inspection object 11 has a form of a rotating body. Here, the “rotating body” refers to a three-dimensional body generated by rotating around one axis. In this embodiment, it is assumed that the inspection object 11 has a cylindrical shape having a certain thickness for the sake of simplicity. The test object 11 is placed in a state of being put in the water 13 in the water tank 12. A rotary table 14 is provided in the water tank 12, and the inspection object 11 is fixed on the rotary table 14 with its axis aligned with the axis of the rotary table 14. That is, the inspection object 11 is arranged in an upright state on the turntable 14. The rotary table 14 is the water tank 1
2 is fixed to an output shaft 15 a of a motor 15 provided outside and rotated by the motor 15. As the rotary table 14 rotates, the inspection object 11 also rotates around its axis. Since the inspection object 11 has a cylindrical shape having a large thickness, the side surface forming the peripheral portion is a cylindrical portion. The rotation operation of the inspection object 11 rotated by the motor 15 is performed based on predetermined control as described later.

A probe (also called a probe) 16 is arranged outside the side surface of the inspection object 11. Probe 1
Reference numeral 6 faces the outer surface of the side surface. Probe 16 is water 13
It is provided so that it can move in the water. The device that moves the probe 16 is a driving robot 17. The drive robot 17 is, for example, a commercially available orthogonal robot. In this example, the horizontal direction (X-axis direction) in FIG.
This is a two-axis orthogonal type robot that can be moved in a direction perpendicular to the Z axis direction. The driving robot 17 is usually provided above and outside the water tank 12. In FIG. 1, the illustration of the configuration for supporting the driving robot 17 is omitted. FIG. 2 shows an enlarged main part of the driving robot 17.

The driving robot 17 will be described with reference to FIGS. The drive robot 17 includes an X-axis drive mechanism 17a that enables movement in the X-axis direction and a Z-axis drive mechanism 17b that enables movement in the Z-axis direction. In the configuration shown in FIG. 1, the X-axis direction is set so as to coincide with the radial direction of the inspection object 11, and the Z-axis direction is set so as to coincide with the axial direction of the inspection object 11.

The X-axis drive mechanism 17a comprises a motor section 51 and a main body section 52. The motor unit 51 is provided with a detection unit 53 for detecting a motor operation amount. The main body 52 is fixed to a support (not shown), and its position does not change. The elongated main body 52 is fixed so that its length direction is oriented in the X-axis direction. The main body 52 is provided with a rail 54 oriented in the X-axis direction, and the rail 54 is provided with a slider 55 that freely moves in the X-axis direction. Any structure can be used for the structure of the rail and the slider. The movement of the slider 55 in the X-axis direction is
1 is performed. The movement amount of the slider 55 is detected by a detection unit (encoder or the like) 53. Motor unit 51
Is performed based on a command signal given from the robot controller 23 described later. A signal relating to the operation amount of the motor unit 51 is provided from the detection unit 53 to the robot controller 23.

Similarly, the Z-axis driving mechanism 17b
And a main body 62. The motor unit 61 is provided with a detection unit 63 for detecting a motor operation amount. The main body 62 is fixed to the slider 55 of the X-axis drive mechanism 17a.
The elongated main body 62 is arranged so that its length direction is oriented in the Z-axis direction. Therefore, the entire Z-axis drive mechanism 17b is moved in the X-axis direction by the X-axis drive mechanism 17a. The main body 62 has a rail 6 oriented in the Z-axis direction.
4 is provided, and a rail 64 is provided with a slider 65 that freely moves in the Z-axis direction. The movement of the slider 65 in the Z-axis direction is performed by the operation of the motor unit 61. The moving amount of the slider 65 is detected by a detection unit (encoder or the like) 63. The operation of the motor unit 61 is performed based on a command signal given from the robot controller 23. A signal relating to the operation amount of the motor unit 61 is provided from the detection unit 63 to the robot controller 23. Further, the slider 65
An arm 17c arranged in the Z-axis direction is fixed to the vertical piece 65a (shown in FIG. 3). Arm 17c
Are parallel to the rail 64. In FIG. 1, the rail 6
4 is hidden by the arm 17c.

In the driving robot 17 having the above configuration, the probe 16 is attached to the lower end of the arm 17c. The probe 16 provided at the lower end of the arm 17c is freely moved in each direction of the X axis and the Z axis by a combination of the operations of the X axis driving mechanism 17a and the Z axis driving mechanism 17b of the driving robot 17. .

In the description of this embodiment, in particular, regarding the change in the position of the probe 16 with respect to the inspection object 11, the change in the circumferential direction (rotation direction) of the inspection object 11 in FIG. The change in the axial direction (Z-axis direction) is emphasized. When the rotary table 14 is rotated by the operation of the motor 15, the inspection object 11 is also rotated. Due to the operation of the X-axis drive mechanism 17a of the drive robot 17, the probe 16 is arranged at a close position outside the side surface of the inspection object 11. Further, the probe 16 moves the Z-axis by the operation of the Z-axis driving mechanism 17b.
Reciprocate in the axial direction. In this embodiment, when the inspection object 11 is rotated once, the probe 1
6 is reciprocated once in the Z-axis direction. As a result, as a change in the relative position between the side surface portion of the inspection object 11 and the probe 16, the probe 16 makes one rotation around the cylindrical side surface portion of the inspection object 11 during the rotation. Inspection object 1
It is moved so as to make one reciprocation by one axial length.

The apparatus of the present embodiment includes an operating device 21 used by an operator for inputting various commands and data, and inputs commands and the like from the operating device 21 to control the operation of the entire device. Controller 22, a robot controller 23 for controlling the operation of the driving robot 17, an object rotating device 24 for executing a rotating operation of the motor 15 (a rotating operation of the object 11), and the probe 16. To periodically apply a pulse signal to apply a pulsed ultrasonic wave to the inspection object 11 and receive a reflected wave to detect a defect pulse or the like, and to detect an internal defect or a surface flaw on the side surface of the inspection object 11. Inspection device 25 for measuring and inspecting
Is provided. The operation device 21 is a device for performing teaching. The motor 15 is provided with a tachometer (encoder or the like) 26 for measuring the amount of rotation.
The rotation operation amount of the motor 15 detected by the tachometer 26, that is, data on the rotation operation amount of the inspection object 11 is sent to the sequence controller 22. The data of the rotation operation amount is used for synchronous control. The flaw detector 25 includes a pulse generation circuit, a reception circuit, a gate circuit, a data processing circuit,
An image data generation circuit, a display device, and the like are provided. These configurations of the flaw detector 25 are basically well-known configurations.

Next, in the ultrasonic flaw detection system having the above-described configuration, the measurement / inspection of the side surface of the inspection object 11 in the form of a rotating body based on the method of the present embodiment will be described with reference to FIGS. This will be described with reference to FIGS. The ultrasonic flaw detection method according to the present embodiment measures the side surface portion of the inspection object 11 preferably with the probe 16 from an outer position thereof, and performs the probe operation based on a positional change relative to the inspection object 11. When the child 16 is moved, a predetermined synchronous relationship is established between the movement of one rotation in the circumferential direction and the reciprocation in the axial direction. It is characterized in that the inspection start position is shifted by a predetermined amount (that is, an offset is given).

At the initial stage of starting the flaw detection measurement, the probe 16 is located at the upper end of the inspection object 11 in the Z-axis direction as shown in FIG. 1 and in the circumferential direction of the inspection object 11. Is located at point a1 as shown in FIG. In this state, when the motor 15 starts rotating based on the command signal of the inspection object rotating device 24, the Z drive mechanism 17b of the driving robot 17 simultaneously moves the probe 16 in the Z-axis direction based on the command signal of the robot controller 23. And move it down. When the probe 16 reaches the lower end of the inspection object 11, the probe 16 moves upward and moves to the upper end of the inspection object 11. The probe 16 makes one reciprocation in the Z-axis direction while the inspection object 11 makes one rotation, in other words, while the probe 16 makes one rotation in the circumferential direction on the side surface of the inspection object. It is controlled synchronously. The rotation of the motor 15 and the Z-axis driving mechanism 17 are performed so that the above-described movement can be performed.
The operation is synchronized with the operation b.

Due to the change in the relative position between the object 11 and the probe 16, the probe 16 substantially moves the side surface around the object 11 to the outer position in the circumferential direction. The measurement / inspection is performed so as to make one reciprocation in the axial direction while making one rotation and return to the original position a1. Probe 16
Performs a normal ultrasonic inspection according to the inspection operation based on the inspection apparatus 25 during the movement. That is, a drive pulse is periodically generated and supplied to the probe 16, and the probe 1
At step 6, ultrasonic waves are periodically generated. This ultrasonic wave is applied so as to advance in the radial direction on the side surface of the inspection object 11. If a defect or the like exists on the surface or inside of the inspection object 11, a reflected wave is generated, and the reflected wave returns to the probe 16. The probe 16 sends these signals to the flaw detector 25 while receiving the reflected waves returning from the inside of the inspection object 11. The flaw detector 25 receives the signal of the reflected wave from the probe 16 and processes and stores the flaw detection data. By the combination of each rotation of the inspection object 11 and one reciprocation of the probe 16 therebetween, the probe 16 is substantially in a spiral shape with respect to the outer surface of the side surface of the inspection object 11. Measurement and inspection of flaw detection are performed by drawing an inspection trajectory. In addition, the inspection object 1
When one side surface portion is developed and shown, one spiral inspection trajectory (inspection line) is virtually drawn.

When the flaw detection measurement by the first rotation is completed, the flaw detection measurement by the next one rotation is performed. When performing the next flaw detection measurement, as shown in FIG. 3, the point where measurement / inspection is first started is shifted from point a1 to point a2. The shift amount from the point a1 to the point a2 is set as θ. Shift amount θ
Is defined as an offset amount. The value of the shift amount θ can be set arbitrarily according to the purpose of measurement and inspection.
The flaw detection measurement by the next one rotation starts from the point a2, and similarly to the flaw detection measurement by the first one rotation described above, the circumferential movement of the inspection object 11 and the reciprocation of the probe 16 in the Z-axis direction. By the combination with the operation, the flaw detection measurement based on the second one rotation by the probe 16 from the outside of the side surface of the inspection object 11 is performed. As a result, as in the first flaw detection measurement, one spiral inspection trajectory can be obtained.

When the second flaw detection measurement is completed, the process proceeds to the next third flaw detection measurement. At this time, the point at which the measurement is started is as shown in FIG.
After shifting to 3, the flaw detection measurement is started. The operation of the third flaw detection measurement is the same as each of the flaw detection measurements described above, and is performed by a combination of a rotation operation of the inspection object 11 in the circumferential direction and a reciprocation operation of the probe 16 in the axial direction. As a result, 1
A spiral inspection trajectory of a book can be obtained.

Thereafter, as shown in FIG. 3, the fourth and fifth flaw detection measurements are performed in the same manner as described above while shifting the start point of the flaw detection measurement by the offset amount θ. The number of flaw detection measurements is determined in relation to the required fineness of the measurement, the size of the inspection object, the measurement time, and the like. When the number of inspection lines to be obtained by the flaw detection measurement is, for example, 10, the offset amount θ is 360 ° / 10 = 36 °. 36 °
By shifting the starting point of the flaw detection measurement every time, ten spiral inspection trajectories can be obtained.

FIG. 4 is an expanded view of the side surface of the inspection object 11. In the drawing, reference numeral 31 denotes a spiral inspection trajectory (inspection line). According to the above-described ultrasonic inspection method according to the present embodiment, it is possible to obtain a plurality of inspection lines that are helical inspection lines as illustrated and that are shifted at a predetermined offset amount at substantially equal intervals. Can be. Such a spiral inspection line 31 is obtained by the data processing circuit of the flaw detector 25.

As is apparent from FIG. 4, according to the ultrasonic inspection method for the inspection object 11 in the form of a rotating body according to the present embodiment,
In particular, in the inspection object 11, a defect 32
When this occurs, it is possible to effectively detect this. In particular, according to this flaw detection method, even if the number of inspection lines 31 is small, it is easy to find a defect in the radial direction or the like, and the defect in the radial direction can be inspected in a short time.

In the description of the above embodiment, the inspection object 11
The measurement is performed by the probe 16 from the outside of the side surface portion. However, it is needless to say that the probe 16 can be arranged inside the side surface portion to perform the flaw detection measurement from the inside.

In the above embodiment, the inspection object 11 is a cylindrical body. However, as a specific example of the rotating body inspection object, a mechanical part having an electron beam welding portion or a pressure welding portion (such as an automobile part) may be used. ), Engine cylinders and the like.

Next, another embodiment of the ultrasonic flaw detection method and apparatus according to the present invention will be described. The system configuration as the ultrasonic flaw detector is the same as that described with reference to FIGS. The difference lies in the operation of the motor 15 controlled by the sequence controller 22 and the manner of operation of the probe 16 by the Z-axis driving mechanism 17b of the driving robot 17. In the above-described embodiment, the offset amount θ is set in the circumferential direction when performing the flaw detection measurement for acquiring each inspection line 31. However, in the present embodiment, by setting the offset amount in the Z-axis direction, Flaw detection measurement is performed. That is, when performing the flaw detection measurement to obtain the aforementioned inspection line 31, the inspection object 11 is rotated once by the motor 15, and the probe 16 is moved by the Z of the driving robot 17.
One reciprocation is performed by the shaft driving mechanism 17b. In this case, one rotation of the probe 16 with respect to the inspection object 11 as relative movement always starts from the same position without setting an offset amount. In the one reciprocating movement of the child 16 in the Z-axis direction, the movement start point is shifted by the set offset amount. As a result, as shown in FIG. 4, a plurality of equally-spaced spiral inspection lines similar to those in the above-described embodiment can be obtained. The ultrasonic inspection method according to this embodiment can also easily inspect the side surface of the rotating body inspection object 11 for a defect such as a radial direction in a short time.

[0035]

As is apparent from the above description, according to the method and apparatus for ultrasonic flaw detection according to the present invention, the ultrasonic flaw detection for detecting a defect generated in a rotating body inspection object in a radial direction or the like is performed. The probe is measured from the outside or inside of the side surface of the object to be inspected, and the probe is moved once in the axial direction while making one rotation in the circumferential direction of the object to perform the flaw detection measurement. Further, since such flaw detection measurement is repeatedly performed while shifting the measurement start point by a predetermined amount in the circumferential direction or the axial direction, a plurality of spiral inspection lines at equal intervals can be obtained, and the diameter of the inspection line can be obtained by the inspection lines. It is possible to detect defects in the direction and the circumferential direction in a short time and effectively.

[Brief description of the drawings]

FIG. 1 is a configuration diagram showing an entire system configuration of an ultrasonic inspection apparatus for a rotating body inspection object according to the present invention.

FIG. 2 is an enlarged perspective view showing a part of a driving robot.

FIG. 3 is a plan view of the inspection object for explaining a state in which a measurement start position is shifted in a circumferential direction of the inspection object.

FIG. 4 is a view showing a spiral inspection line obtained by the ultrasonic inspection method according to the present invention in a state where a side surface of the inspection object is developed.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 11 Inspection object 12 Water tank 13 Water 14 Rotary table 15 Motor 16 Probe 17 Drive robot 31 Inspection line 32 Defect

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Toshimitsu Takahashi 650, Kandamachi, Tsuchiura-shi, Ibaraki F-term in the Tsuchiura Plant of Hitachi Construction Machinery Co., Ltd. (Reference) 2G047 AB01 AB07 AC05 DB03 DB17 GA06 GA19 GB04 GG01

Claims (6)

[Claims] A probe is disposed so as to face a side surface portion of a rotating object, and a relative positional relationship between the probe and the side surface of the inspection object is as follows. The probe is
An ultrasonic flaw detection method for rotating along the surface of the side surface part in the circumferential direction of the inspection object and moving in the axial direction at the same time, thereby performing flaw detection on the side surface part of the inspection object, The stylus makes one reciprocation at the same time when it makes one rotation, and repeats this flaw detection operation while setting the shift amount,
In this way, a plurality of spiral inspection trajectories are drawn at substantially equal intervals on the entire surface of the side surface portion. 2. The inspection trajectory is drawn by shifting the inspection start position by a predetermined amount in the circumferential direction when the probe starts the one rotation. 2. The ultrasonic inspection method for a rotating body inspection object according to 1. 3. A plurality of said inspection trajectories are drawn by shifting an inspection start position by a predetermined amount in said axial direction when said probe starts said one rotation. An ultrasonic flaw detection method for a rotating body inspection object according to the above description. 4. A probe is disposed so as to face a side surface of a rotating object, and a relative positional relationship between the probe and the side surface of the object is as follows. The probe is
An ultrasonic flaw detector that rotates along the surface of the side surface in the circumferential direction of the object and moves in the axial direction at the same time, thereby performing flaw detection on the side surface of the object to be inspected. A rotation drive mechanism for rotating the object to be inspected around its axis; and a reciprocating unit that includes the probe on an arm, and reciprocates the probe in the axial direction by approaching the probe to the side surface of the object to be inspected. A control mechanism for controlling the rotation drive mechanism and the reciprocating drive mechanism so that the probe is reciprocated one time simultaneously in synchronization when the probe makes one rotation, and the flaw detection operation is repeated while setting a shift amount. Ultrasonic inspection equipment for a rotating object to be inspected, wherein a plurality of spiral inspection trajectories are drawn at substantially equal intervals over the entire side surface of the object to be inspected. . 5. The rotation according to claim 4, wherein said control means controls the inspection start position to be shifted by a predetermined amount in the circumferential direction when the probe starts the one rotation. Ultrasonic flaw detector for body inspection objects. 6. The rotating body according to claim 4, wherein said control means controls the inspection start position to be shifted by a predetermined amount in said axial direction when said probe starts said one rotation. Ultrasonic flaw detector for inspection objects.