JP2000162195A - Ultrasonic piping measuring device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve the measurement precision and working efficiency of measurement in the measurement by two-dimensional scanning of the surface of a piping. SOLUTION: In an ultrasonic measuring head 3, an emitting hole 30c communicating with a water-tight space 33 is reduced in diameter, so that the water filled in the water-tight space 33 is protruded from the emitting hole 30c by surface tension so as to form a protruding part. A regulating shaft 31 is regulated so that the protruding part of the water protruded from the emitting hole 30c makes contact with the surface of a piping 1. The ultrasonic beam from an ultrasonic probe 32 is converged toward the surface of the piping 1, and emitted through the emitting hole 30c.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ultrasonic pipe measuring apparatus for irradiating ultrasonic waves to a pipe to non-destructively measure the thickness of the pipe and detect flaws.

[0002]

2. Description of the Related Art Conventionally, as an ultrasonic measuring apparatus for measuring the thickness of a pipe in a non-contact manner, a water jet type ultrasonic measuring head is two-dimensionally scanned in the axial direction and the circumferential direction of the pipe. Devices for performing are known. 5 and 6 show this conventional ultrasonic measuring apparatus.

In FIG. 5, a scanning mechanism 102 for two-dimensionally scanning the surface of the metal pipe 101 is detachably mounted on the metal pipe 101, and an ultrasonic measuring head 103 is mounted on the scanning mechanism 102. At the time of measurement, the pump 104 is operated in advance, and water in the water supply tank 105 is jetted from the tip of the ultrasonic measurement head 103. Next, when the personal computer 109 is instructed to start measurement, a command is applied to the drive circuit 106 in accordance with a previously input operation procedure, the drive motors 102D and 102E are operated, and the ultrasonic measurement head 103 cleans the surface of the metal pipe 101. Scan two-dimensionally.

At a desired position in the two-dimensional scanning, the pulser / receiver 107 applies an ultrasonic measurement pulse to the ultrasonic measurement head 103 and receives an ultrasonic reflection echo according to a command from the personal computer 109, and receives the ultrasonic reflected echo. The signal is output to the time measurement circuit 108. The time measuring circuit 108 counts the time between the reflected echo pulse trains and outputs the result to the personal computer 1
09 is output. The personal computer 109 converts the input value into a thickness and outputs the result to the display device 110 as numerical values and one-dimensional or two-dimensional image data.

The scanning mechanism 102 will be described. An axial scanning unit 102B and a rotary scanning unit 102C are mounted on an adapter 102A fixed to a metal pipe 101. In the axial scanning unit 102B, a driving motor 102D
The ultrasonic measuring head 103 moves in the axial direction by the transport action of the screw shaft rotated by the rotation. In the rotary scanning unit 102C, the rotary scanning unit 10A is fixed to the adapter 102A fixed by the rotational driving of the driving motor 102E.
2C is rotated in the circumferential direction.
The axial scanning unit 102B fixed to the 2C frame moves in the circumferential direction in parallel with the rotation of the rotary scanning unit 102C. Here, the adapter 102A is a half-split ring-shaped member, and is detachably fixed around the metal pipe 101 by bolts.

[0006] To explain the ultrasonic measuring head 103, as shown in Fig. 6, an ultrasonic probe 103A is built in an upper part of a water column nozzle 103B, and supplied from a pump through a water inlet 103C. The water 103D fills the gap inside the nozzle and between the nozzle and the metal pipe 101 to form an ultrasonic wave propagation path. For this reason, the measurement can be performed without contact between the ultrasonic measurement head 103 and the metal pipe 101.

[0007]

The above-mentioned conventional ultrasonic measuring apparatus has the following problems. First, in the ultrasonic measurement head, water is constantly jetted out at the time of measurement to form an ultrasonic wave propagation path. According to this, when measuring the upper surface of the pipe, water is ejected in the direction of gravity, so that the propagation path of the ultrasonic wave can be uniformly filled with water, and highly accurate measurement is possible. When measuring the bottom surface, the direction of water ejection and the direction of gravity are different, so it is difficult to fill the ultrasonic propagation path with water in a uniform state, and air is mixed into the ultrasonic propagation path and noise occurs There is a problem that a reflected wave is generated, which makes it difficult to measure with high accuracy.

In addition, since the water jetting type ultrasonic measuring head is in a state where water drips, it is necessary to supply a large amount of water, which is uneconomical. Care must be taken to prevent the electronic equipment such as the device from getting wet, which hinders the quickness of the measurement operation. Furthermore, in the scanning mechanism, it takes time to attach the adapter to the pipe, which also hinders a quick measurement operation.

SUMMARY OF THE INVENTION The present invention has been proposed in order to cope with the above-described circumstances. In an ultrasonic pipe measuring apparatus for performing measurement by scanning a pipe surface two-dimensionally, the measurement accuracy and the work of the measurement are described. The purpose is to improve efficiency.

[0010]

In order to achieve the above object, an ultrasonic pipe measuring apparatus according to the present invention, as a first invention, emits an ultrasonic beam toward a pipe surface of an object to be measured and generates a reflected echo. An ultrasonic measuring head provided with an ultrasonic probe for receiving an ultrasonic wave; and an ultrasonic measuring head detachably mounted on the pipe surface, and two ultrasonic measuring heads in an axial direction and a circumferential direction of the pipe surface.
An ultrasonic pipe measuring apparatus comprising: a scanning mechanism for performing two-dimensional scanning, a position detecting mechanism for grasping two-dimensional position information of the scanning mechanism, and an arithmetic processing device for arithmetically processing a reflected echo received by the ultrasonic measuring head. The sound wave measurement head includes a watertight space in which water is filled in an ultrasonic wave propagation path in the head, and the water in the watertight space forms small holes that form a convex portion to the outside due to surface tension to form the water. An adjusting means for adjusting a distance between the convex portion and the surface of the pipe so that the convex portion is in contact with the surface of the pipe is provided, and the ultrasonic beam is focused so that the small hole serves as an emission hole.

As a second invention, the ultrasonic measuring head according to the first invention is provided with an automatic water supply / drainage device for supplying / draining water to / from the watertight space.

As a third invention, in the first or second invention, the scanning mechanism comprises a slide shaft for sliding the ultrasonic head in the axial direction, a frame member for supporting the slide shaft, and a frame member for supporting the slide member in the circumferential direction. , And a position detecting mechanism for grasping two-dimensional position information, wherein the drive wheel includes a permanent magnet that is attracted to the surface of the pipe.

The operation of the first to third aspects will be described.

In the first invention, first, an ultrasonic beam emitted from a probe in an ultrasonic measuring head is focused to form a focused ultrasonic beam which is focused at one point on the surface of a pipe to be measured. I have. Then, a watertight space in which water is filled in the propagation path of the ultrasonic beam is formed. further,
The exit hole from which the ultrasonic beam exits from the ultrasonic measurement head is configured as an extremely small hole so that water in the watertight space forms a convex portion from the exit hole to the outside due to surface tension. Then, the gap with the pipe surface is adjusted so that the convex portion of the water just contacts the surface of the pipe.

Thus, the ultrasonic beam itself can be a beam having a very small dead zone which is focused on the surface of the pipe, and an ultrasonic measuring head which does not emit water while using water as a contact medium can be constructed. According to this ultrasonic measurement head, even if the head is rotated and scanned in the circumferential direction of the pipe to change the posture, the watertight space can always be filled with water. There is no inconvenience that air enters the sound wave propagation path, and stable and reliable measurement can be performed. In addition, the head itself is not in contact with the pipe surface, so that the convex portion of water projecting from the output hole of the head by surface tension comes in contact with the pipe surface, so that the life of the head can be kept long, The function as a contact medium can be secured without dripping water.

According to the second aspect of the invention, in addition to the above-mentioned functions, the water supply and drainage to the watertight space is performed by an automatic water supply / drainage device, so that the water pressure in the watertight space can be controlled to be constant. Even if air enters the watertight space, the air can be quickly eliminated.

According to a third aspect of the present invention, in addition to the above-described operation, the scanning mechanism slides the ultrasonic head in the axial direction, a frame member supporting the slide shaft, and the frame member is moved in the circumferential direction. A drive wheel and a position detection mechanism (encoder counter) for grasping two-dimensional position information are provided, and the drive wheel is provided with a permanent magnet that is attracted to a pipe surface. It can be quickly mounted on the surface of the pipe to be measured, and the work efficiency of the measurement work can be improved.

[0018]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments including the first to third inventions will be described below with reference to the drawings.

FIG. 1 is a system configuration diagram of an ultrasonic pipe measuring apparatus according to one embodiment of the present invention. Reference numeral 1 denotes a pipe to be measured, reference numeral 2 denotes a scanning mechanism, reference numeral 3 denotes an ultrasonic measurement head, reference numeral 4 denotes a control device, reference numeral 5 denotes an automatic water supply / drainage device for supplying / draining water to / from the ultrasonic measurement head, and reference numeral 6 denotes a super Reference numeral 7 denotes a data recording / analysis / encoder counter control device, and reference numeral 8 denotes a display device.

A scanning mechanism 2 for two-dimensionally scanning the surface of the pipe 1 is detachably mounted on the pipe 1, and an ultrasonic measuring head 3 is mounted on the scanning mechanism 2. At the time of measurement, the automatic water supply / drainage device 5 is operated to supply / drain water to / from the ultrasonic measurement head 3. Next, when the power of the ultrasonic flaw detector 6 is turned on, the data recording, analysis, and the encoder counter controller 7 are enabled to be measured, and the control device 4 is instructed to start measurement, the scanning mechanism 2 is operated in accordance with a previously input operation procedure. Is driven, and the ultrasonic measurement head 3 two-dimensionally scans the surface of the pipe 1. Here, at a desired position of the two-dimensional scanning, the ultrasonic flaw detector 6 applies an ultrasonic measurement fixed pulse to the ultrasonic measurement head 3 and receives an ultrasonic reflection echo, and records and analyzes the received signal. Device 7
Output to The data recording / analyzing device 7 calculates the thickness of the pipe by processing the received signal, and outputs the result to the display device 8 as numerical values and one-dimensional or two-dimensional image data.

FIG. 2 is an explanatory view showing an ultrasonic measuring head 3 of the ultrasonic pipe measuring apparatus according to one embodiment of the present invention.
Reference numeral 30 denotes a head body, and adjustment shafts 31 are provided on both left and right sides of the head body 30. The adjustment shaft 31 has a screw adjustment mechanism for adjusting the interval between the emission surface 30a of the head main body 30 and the surface of the pipe 1 to be measured and the inclination of the head main body 30. Is provided with a ball bearing so that the head body 30 can slide smoothly on the surface of the pipe 1. An ultrasonic probe 32 is mounted on the upper surface 30b of the head main body 30. The ultrasonic probe 32 emits an ultrasonic beam to the surface of the pipe 1, receives a reflected echo from the pipe 1, and transmits a received signal to the data recording / analyzing device 6 described above. An ultrasonic wave focusing means is provided on the ultrasonic wave propagation path from the ultrasonic probe 32, and the ultrasonic beam emitted toward the pipe 1 is focused on the surface of the pipe 1 at one point.

A watertight space 33 filled with water is formed in the ultrasonic wave propagation path in the head body 30.
An emission hole 30 c for emitting the focused ultrasonic beam is formed in the emission surface 30 a of the head main body 30, and communicates with the watertight space 33. Further, a water supply passage 34 and a drain passage 35 are connected to the watertight space 33 so that the inside air is excluded and the water is filled. Here, by making the hole diameter of the drain passage 35a in the head main body 30 larger than the hole diameter of the water supply passage 34a in the head main body 30, the air in the watertight space 33 is discharged well. The water supply channel 34 and the drainage channel 35 are connected to the automatic water supply / drainage device 5 described above.

According to the ultrasonic measuring head 3 described above, the water filled in the watertight space 33 is reduced by the surface tension so that the outlet hole 30c communicating with the watertight space 33 is made a small hole.
A projection is formed from c to protrude. In order to form the convex portion, the hole diameter of the exit hole 30c is set appropriately, and the amount of water supply / drainage from the water supply channel 34 or the drainage channel 35 is automatically set in order to properly set the water pressure in the watertight space 33. It is necessary to adjust by the plumbing device 5. Then, the adjustment shaft 31 is adjusted so that the convex portion of the water protruding from the emission hole 30c is in contact with the surface of the pipe 1.

FIG. 3 is an explanatory view showing the scanning mechanism 2 of the ultrasonic pipe measuring device according to one embodiment of the present invention. FIG. 1A is a front view as viewed from above, and FIG. 1B is a side view. The frame member 20 supports a slide shaft 21, and the ultrasonic measurement head 3 is mounted on the slide shaft 21 via a slide mechanism 36 so as to be slidable in the axial direction. The frame member 20 includes a stepping motor 22 for driving in the axial direction and a stepping motor 2 for driving in the circumferential direction.
3 is installed.

The scanning in the axial direction will be described. A drive pulley 24a driven by the stepping motor 22 is provided at one end of the frame member, and a driven pulley 24b is provided at the other end, and an encoder counter 29 that follows the driven pulley 24b is mounted. A drive belt 25 is hung on the drive pulley 24a and the driven pulley 24b.
The slide mechanism 36 is mounted on a part of the slide 5.
24c, 24c are intermediate pulleys for guiding the drive belt 25. Thus, by driving the stepping motor 22, the drive belt is moved, and the slide mechanism 36 is moved along the slide axis.

The scanning in the circumferential direction will be described. A drive pulley 26a and a driven pulley 26b driven by the stepping motor 23 are mounted on one end of the frame member. A driving belt 27 is provided on the driving pulley 26a and the driven pulley 26b.
, And the driving belt 28 is driven to rotate. Further, the stepping motor 22,
23 is controlled by a signal from the control device 4,
The ultrasonic measurement head 2 can be sequentially scanned in the axial direction and the circumferential direction. Here, a permanent magnet is mounted on the drive wheel 28, and this allows the entire scanning mechanism 2 to be attracted to the pipe surface. In order to recognize the circumferential position, a follower wheel 28 'made of a permanent magnet may be provided separately from the circumferential drive wheel 28, and an encoder 28a may be mounted on the follower wheel shaft. Thus, even if the circumferential follower wheel slips, the position information is transmitted accurately.

The operation of the above embodiment will be described. First, the scanning mechanism 2 is mounted on the surface of the pipe 1. This only requires the drive wheels 28 of the scanning mechanism 2 to be attracted to the surface of the pipe 1 by the action of the permanent magnet. Then, while the scanning mechanism 2 is driven and the ultrasonic measurement head 3 scans the pipe surface two-dimensionally, the pipe 1 is measured for thickness and the like. FIG. 4 is an explanatory diagram showing an example of the scanning procedure. Origin X = 0, Y = 0
(X: axial direction, Y: circumferential direction) Ultrasonic measuring head 3
Is driven stepwise at a constant interval in the X direction by the driving of the stepping motor 22 and reaches the end point X = X. By driving the stepping motor 23, the driving wheels rotate to move the entire scanning mechanism 2 in the circumferential direction. The ultrasonic measurement head 3 is moved one step in the Y direction. Next, it is stepped in the opposite direction until X = 0, and when it reaches X = 0, Y
It is sent one step in the direction. Such an operation is performed at the end point X =
By repeating X, Y = Y, the ultrasonic measurement head 3 is two-dimensionally scanned on the surface of the pipe 1.

Before measurement, an automatic water supply and drainage device 5
Is operated to fill the water-tight space 33 of the ultrasonic measurement head 3 with water to discharge air. And watertight space 3
The water pressure in the inside 3 is adjusted so that a projection of water due to surface tension is always formed from the emission hole 30c even when the ultrasonic measurement head 3 is scanned in the circumferential direction. The convex portion of the water comes into contact with the surface of the pipe 1 at the time of measurement and acts as a contact medium.

According to this, the ultrasonic beam itself is connected to the pipe 1
The beam can be formed as an extremely small beam with a dead zone converging on the surface of the surface, and the ultrasonic measurement head 3 which does not emit water while using water as a contact medium can be configured. According to the ultrasonic measurement head 3, even if the head is scanned in the circumferential direction of the pipe 1 to change the posture, the watertight space 33 can always be filled with water. There is no inconvenience that air enters the sound wave propagation path, and stable and reliable measurement can be performed.

Further, the head itself is not in contact with the surface of the pipe 1, and the convex portion of water projecting from the exit hole 33c of the head by surface tension comes into contact with the surface of the pipe 1. Can be maintained for a long time, and the function as a contact medium can be ensured without flowing water.

Further, since the water supply and drainage to the watertight space 33 is performed by the automatic water supply and drainage device 5, the watertight space 33 is provided.
The internal water pressure can be controlled to be constant, and even if air enters the watertight space 33, the air can be quickly removed.

The scanning mechanism 2 includes a slide shaft 21 for sliding the ultrasonic measuring head 3 in the axial direction and a slide shaft 2.
1 and a drive wheel 28 for moving the frame member 20 in the circumferential direction.
Since the scanning mechanism 2 is configured to have a permanent magnet that is attracted to the surface of the pipe 1, the scanning mechanism 2 can be quickly mounted on the surface of the pipe to be measured, and the work efficiency of the measurement operation can be improved. .

[0033]

Since the present invention is configured as described above,
The following effects are obtained. (1) Even if the ultrasonic measuring head rotates around the pipe axis,
Since air does not enter the propagation path of the ultrasonic wave, stable and reliable measurement can be performed. (2) Since the ultrasonic measuring head does not emit water, the trouble of waterproofing the measuring device can be omitted. (3) The attachment / detachment of the scanning mechanism to / from the pipe becomes easy, and the work efficiency of the measurement work is improved. (4) Since the ultrasonic measurement head is basically in non-contact with the pipe, it is possible to extend the life of the head. (5) Since the ultrasonic beam is focused on the surface of the pipe, the dead zone is extremely small.

[Brief description of the drawings]

FIG. 1 is a system configuration diagram of an ultrasonic pipe wall thickness measuring device according to one embodiment of the present invention.

FIG. 2 is an explanatory view showing an ultrasonic measuring head of the ultrasonic pipe wall thickness measuring device according to one embodiment of the present invention.

FIG. 3 is an explanatory view showing a scanning mechanism of the ultrasonic pipe thickness measuring device according to one embodiment of the present invention.

FIG. 4 is an explanatory diagram showing an example of a scanning procedure according to an embodiment of the present invention.

FIG. 5 is an explanatory diagram of a conventional example.

FIG. 6 is an explanatory diagram of a conventional example.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Piping 2 Scanning mechanism 3 Ultrasonic measuring head 4 Control device 5 Automatic water supply / drainage device 6 Ultrasonic flaw detection device 7 Data recording / analysis / encoder counter control device 8 Display device

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Yutaka Arai 2-7-18 Shinkoyasu, Kanagawa-ku, Yokohama-shi, Kanagawa F-term (reference) GA01 GA06 GA19 GB24 GE02 GE03 GF18 GJ07 GJ16

Claims (3)

[Claims] 1. An ultrasonic measuring head having an ultrasonic probe for emitting an ultrasonic beam toward a surface of a pipe to be measured and receiving a reflected echo, the ultrasonic measuring head being detachably mounted on the pipe surface. A scanning mechanism for scanning the ultrasonic measurement head two-dimensionally in the axial direction and the circumferential direction of the pipe surface, a position detection mechanism for grasping the two-dimensional position information, and an arithmetic processing of a reflected echo received by the ultrasonic measurement head An ultrasonic pipe measuring apparatus comprising an arithmetic processing unit, wherein the ultrasonic measuring head includes a watertight space in which water is filled in an ultrasonic wave propagation path in the head, and the water in the watertight space is caused by surface tension. An adjusting means for forming a small hole that forms a convex portion on the outside and adjusting an interval with the pipe surface so that the water convex portion is in contact with the pipe surface is provided, and the ultrasonic beam is focused and Ultrasonic pipe measuring device, characterized in that the hole and the exit aperture. 2. The ultrasonic pipe measuring device according to claim 1, wherein the ultrasonic measuring head is provided with an automatic water supply and drainage device for supplying and draining water to and from the watertight space. 3. The scanning mechanism includes a slide shaft for sliding the ultrasonic head in an axial direction, a frame member for supporting the slide shaft, a driving wheel for moving the frame member in a circumferential direction, and two-dimensional position information. And a position detection mechanism that grasps
3. The ultrasonic pipe measuring device according to claim 1, wherein the drive wheel includes a permanent magnet that is attracted to the pipe surface.