JPH1038858A - Ultrasonic flaw detecting survey instrument for nuclear reactor pressure vessel - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an ultrasonic flaw detecting survey instrument for a nuclear reactor pressure vessel that can ultrasonically detect and inspect a flaw of a nozzle-drum weld part while avoiding an obstruction by remote operation even when a member provided near a nozzle of a nuclear reactor pressure vessel becomes an obstruction to ultrasonic flaw detection and inspection. SOLUTION: In an ultrasonic flaw detecting survey instrument for ultrasonically detecting a flaw of a nozzle weld part of a nuclear reactor pressure vessel by a probe module 50, a fixed arm 30 is erectly provided at a base 20 moving along the periphery of a nozzle, and a moving arm 40 is provided movably in the longitudinal direction along the fixed arm 30. This moving arm 40 is provided with the probe module 50 so as to move longitudinally. When the moving arm 40 interferes with an obstruction, the moving arm 40 is moved by remote operation, and the whole arm is shortened to avoid the obstruction.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ultrasonic inspection apparatus for inspecting a welded portion of a nozzle of a reactor pressure vessel by ultrasonic inspection.

[0002]

2. Description of the Related Art Reactor pressure vessels are inspected during service (I
In SI), a welded portion between the nozzle portion such as the main steam nozzle and the body portion is periodically subjected to ultrasonic inspection. FIG. 5 shows a nozzle-body weld of the reactor pressure vessel.

As shown in FIG. 5, a main steam nozzle 2, a make-up water nozzle, and the like are connected to the reactor pressure vessel 1 by welding to a body portion thereof.

[0004] Ultrasonic flaw detection of the nozzle-body weld 3 such as the main steam nozzle of the reactor pressure vessel 1 is performed by attaching an ultrasonic flaw detection apparatus to the nozzle to be tested and remotely operating the apparatus. It has become.

Conventionally, as an ultrasonic flaw detection apparatus for flaw detection of this nozzle-body weld 3, as shown in FIG.
For example, an ultrasonic flaw detection apparatus t is used in which an arm a is provided upright on a base b moving along the periphery of the nozzle 2 and a probe module m is provided on the arm a so as to move in the longitudinal direction. ing.

When performing an ultrasonic inspection of the welded portion 3 of the nozzle 2 using the inspection device t, an operator attaches the ultrasonic inspection device t around the nozzle 2 and remotely connects the base b to the nozzle b. The ultrasonic inspection for the welded portion 3 was performed while moving the arm a along the welded portion 3 by moving around the probe 2 and moving the probe module m by the rack and pinion mechanism.

[0007]

However, since various members o are provided near the nozzle 2, when the base b is moved and the arm a is moved around the nozzle 2, the member o becomes an obstacle. As a result, interference occurs. As a result, this flaw detection inspection is performed manually, which causes problems such as exposure of workers.

Further, it is conceivable to interrupt the ultrasonic inspection and allow the operator to quickly move the ultrasonic inspection apparatus t to perform the ultrasonic inspection while avoiding the obstacle o. Even if the ultrasonic inspection device t is moved, an obstacle o
Since the module m cannot pass through the inside of the obstacle o sandwiched between the nozzle 2 and the nozzle 2, the inspection must be performed manually by the operator, and the problem of exposure of the operator occurs.

[0009] Therefore, an object of the present invention is to provide a remote pressure control device that can avoid obstacles even if a member provided in the vicinity of a nozzle of a reactor pressure vessel becomes an obstacle for ultrasonic inspection.
It is an object of the present invention to provide an ultrasonic inspection apparatus for a reactor pressure vessel capable of ultrasonic inspection of a nozzle-body weld.

[0010]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention provides an ultrasonic inspection apparatus for ultrasonically inspecting a nozzle-body weld of a reactor pressure vessel using a probe module. A fixed arm is provided upright on a base that moves along the periphery, and a moving arm that moves in the longitudinal direction along the fixed arm is provided, and the probe module is moved to the moving arm in the longitudinal direction. It is provided.

According to the above construction, the base of the ultrasonic inspection apparatus is installed around the nozzle, the base is moved around the nozzle, the entire arm is moved, and the nozzle-body welding portion is ultrasonically inspected. At the time of inspection, when the moving arm and the obstacle approached, the moving arm moved along the fixed arm by remote control, the entire arm was shortened to a length that did not interfere with the obstacle, and was caught between the obstacle and the nozzle Since it is possible to pass through the inside of the obstacle, even if there is an obstacle in the range where the moving arm passes, the ultrasonic flaw detector can be operated remotely to avoid the obstacle and also to inspect the inside of the obstacle.

[0012]

Next, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

FIG. 1 is a side view showing an embodiment of the present invention.

As shown in FIG. 1, an ultrasonic inspection apparatus 10 according to the present invention comprises a base 20 moving around a nozzle of a reactor pressure vessel, and a fixed arm 30 provided upright on the base 20. And a moving arm 40 provided to move in the longitudinal direction along the fixed arm 30 and a probe module 50 provided to the moving arm 40 to move in the longitudinal direction. .

The base 20 is provided with magnet wheels and the like, and is provided rotatably around the nozzle.
Although not shown, the nozzle is rotated around the nozzle by a base moving means.

The fixed arm 30 and the moving arm 40 are provided side by side via a linear guide 32 and an arm moving means 34.
0 is guided along the fixed arm 30, and is moved in the longitudinal direction by the arm moving means 34.

The linear guide 32 is fixed to the fixed arm 30.
These arms 30 and 40
Are provided along the longitudinal direction.

The arm moving means 34 is provided in the fixed arm 30, and has a ball screw 36 erected in the longitudinal direction of the fixed arm 30, and a nut 3 screwed to the ball screw 36.
8 and an arm expansion / contraction motor 44 provided in the moving arm 40 and rotating the nut 38 via the timing belt 42. When the arm extension / retraction motor 44 is operated, the drive of the arm extension / retraction motor 44 is transmitted to the nut 38 via the timing belt 42, and the nut 38 rotates and moves along the ball screw 36. The moving arm 40 also moves along the linear guide 32 to follow the fixed arm 3.
It slides with respect to zero. Although not shown, moving arm holding means for supporting the moving arm 40 so as not to move by gravity and a control device for moving the moving arm 40 are electrically connected to the fixed arm 30.

The moving arm 40 and the probe module 50 are connected via a module moving scanning means 46, and the probe module 50 is moved in the longitudinal direction with respect to the moving arm 40 by the module moving scanning means 46. To move to.

The module movement scanning means 46 includes a probe movement motor 48 provided in the movement arm 40,
An upper timing belt pulley 54 is provided at the upper end on the outer side of the moving arm 40 and is connected to the rotating shaft of the probe moving motor 48 via a bevel gear 52, and is rotatably provided at the lower end of the moving arm 40. And a timing belt 58 wound around the pulleys 56 for the lower timing belt. When the probe movement motor 48 is operated, the probe movement motor 48
Is transmitted to the upper timing belt pulley 54 via the bevel gear 52, and the timing belt 58 rotates to move the probe module 50 in the longitudinal direction. Although not shown, a control device for moving the probe module 50 is electrically connected to the moving arm 40.

Next, the operation of the ultrasonic inspection equipment of the present invention will be described with reference to FIGS.

FIG. 2 is a diagram viewed from the axial direction of the nozzle toward the reactor pressure vessel, and FIG. 3 is a diagram showing the order of movement in an interlocking mode when the entire arm is extended and contracted.

As shown in FIG. 2, when the ultrasonic inspection apparatus 10 of the present invention is used to inspect the welded portion 3 of the reactor pressure vessel by ultrasonic inspection, first, the ultrasonic inspection apparatus 1 is used.
0 base 20 is fixed around the nozzle 2 and the base 20
Is moved around the nozzle 2 by the base moving means, and the fixed arm 30 and the moving arm 40 are moved around the nozzle 2.

As shown in FIG. 3, the probe module 50
Movement of the entire arm in the longitudinal direction depends on the degree of freedom of the probe module 50 with respect to the moving arm 40 and the degree of freedom of the moving arm 4.
It has two degrees of freedom for the fixed arm 30 of 0,
It becomes redundant. Therefore, the movement of the probe module 50 is
There are two methods, a method in which two degrees of freedom are independent of each other, and a method in which they are linked to each other as described later.

For example, the probe module 50 is operated in an interlocking manner.
Move in the direction of the arrow e in the direction of the entire arm. That is, the probe module 5
Until 0 is located at the most distal side with respect to the moving arm 40,
The probe module 50 moves along the moving arm 40. Next, while the probe module 50 is positioned at the most distal end side of the moving arm 40, the moving arm 40 is
It moves in the direction of the tip along zero. And the moving arm 4
When 0 is located at the most distal side with respect to the fixed arm 30, the movement of the probe module 50 in the distal direction of the entire arm ends. When the probe module 50 is moved in the interlocking manner in the root direction of the entire arm, the probe module 50 moves in the order shown in the direction of the arrow s. That is, the order is reversed to the case where the probe module 50 is moved in the distal direction.

In either case, the probe module 50
The length of the entire arm can be reduced to a necessary minimum length according to the amount of movement of the entire arm in the longitudinal direction. Therefore, the obstacle o
Therefore, if the amount of movement of the entire arm of the probe module 50 in the longitudinal direction is small, the entire arm length can be shortened and the obstacle o can be avoided.

Accordingly, the ultrasonic inspection apparatus 10 of the present invention
According to the method, it is possible to perform a flaw detection inspection while avoiding the obstacle o by remotely operating the ultrasonic flaw detection apparatus regardless of the presence or absence of the obstacle o. Can be reduced.

Also, since the ultrasonic inspection apparatus 10 of the present invention can make the entire length of the arm compact, the work of carrying in / out the reactor pressure vessel and the work of attaching / detaching to / from the nozzle can be performed quickly and smoothly. Can be done,
It is possible to reduce the ISI working time.

[0029]

In summary, according to the present invention, even if a member provided in the vicinity of the nozzle becomes an obstacle in the ultrasonic inspection, the obstacle is sandwiched between the obstacle and the obstacle by remote control while avoiding the obstacle. Since the inside of the obstacle that has been damaged can be inspected, the flaw detection inspection manually performed by the operator can be eliminated, and the exposure of the operator can be reduced.

Further, since the entire length of the arm can be made compact, loading and unloading operations to and from the reactor pressure vessel can be performed quickly and smoothly, and the ISI operation time can be reduced.

[Brief description of the drawings]

FIG. 1 is a side view showing an embodiment of the present invention.

FIG. 2 is a view showing a process of shortening the entire arm of the apparatus of FIG. 1;

FIG. 3 is a diagram showing an order of movement in an interlocking mode.

FIG. 4 is a diagram showing a conventional ultrasonic flaw detector.

FIG. 5 is a cutaway perspective view showing a reactor pressure vessel.

[Description of Signs] 10 Ultrasonic flaw detector 20 Base 30 Fixed arm 40 Moving arm 50 Probe module

Continuing from the front page (72) Inventor Yuichi Miura 3-1-1-15 Toyosu, Koto-ku, Tokyo Ishikawajima Harima Heavy Industries Co., Ltd.

Claims (1)

[Claims] An ultrasonic inspection apparatus for ultrasonically inspecting a welded portion of a nozzle of a reactor pressure vessel with a probe module, wherein a fixed arm is provided upright on a base that moves along the periphery of the nozzle. An ultrasonic flaw detection apparatus for a reactor pressure vessel, wherein a moving arm that moves in the longitudinal direction is provided along the fixed arm, and the probe module is provided on the moving arm so as to move in the longitudinal direction. .