JP2001066257A - Pipe inspecting apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a pipe inspecting apparatus capable of sufficiently inspecting a reduction degree of wall thickness up to a lower stage pipe without performing inspection incidental work such as the laying of a rail or the like even if heat exchanger pipes are zigzag arranged in an up and down direction or curved. SOLUTION: A first moving means 2 using the uppermost stage pipes 1a in a heat exanger pipe group 1, wherein heat exchanger pipes are horizontally arranged to a boiler or the like over many stages as a track, the manipulator 6 connected to the first moving means 2 at its one end in a freely revolvable manner and moving along a pipe 1b to be inspected at the other end thereof, and the second moving means 9 for moving on the manipulator 6, are provided. An optical camera 11 being a non- destructive inspection means for inspecting a pipe in a non-destructive manner is arranged on the second moving means 9. Since the first moving means 2 uses the uppermost stage pipes 1a as rails to move, it is unnecessary to lay a rail on the uppermost stage pipes 1a and, since the manipulator 6 is connected to the first moving means 2 in a freely revolvable manner, the non-destructive inspection means mounted on the second moving means 9 can be deeply inserted into the heat exchanger pipe group, wherein the heat exchanger pipes are zigzag arranged in an up and down direction to sufficiently perform inspection up to lower stage pipes.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an inspection apparatus such as a heat exchanger tube of a heat exchanger disposed in a boiler or a refuse incineration plant, and more particularly to an inspection device for an outer surface of a horizontal and staggered heat exchanger tube. The present invention relates to a pipe inspection apparatus suitable for inspecting a thinning state.

[0002]

2. Description of the Related Art The heat exchanger tubes of a boiler are subjected to periodic inspections because they may be corroded or worn by prolonged use and the outer surface of the tubes may be reduced in thickness.

Conventionally, such a thinning condition is inspected by non-destructive means, for example, an inspection device main body moving along a rail laid on the uppermost pipe of a group of boiler steel pipes arranged horizontally. And an optical inspection means provided in the inspection apparatus main body, wherein the inspection is performed while moving the optical inspection means vertically and horizontally (Japanese Patent Application Laid-Open No.
No. 203611) and two rows of adjacent pipes to be inspected in a group of steel pipes are vertically aligned, and then the optical inspection means is attached to a flexible arm, and the optical inspection means is moved vertically. There is known an apparatus for performing inspection while performing the inspection (Japanese Patent Application Laid-Open No. 9-257714).

[0004]

By the way, the horizontal heat exchanger tubes are not only arranged in a narrow boiler,
In order to increase the heat transfer efficiency, they may be arranged in a staggered manner in the vertical direction, or may be curved in the process of being used for a long time.

[0005] Therefore, in the conventional apparatus for inspecting while moving the optical inspection means provided in the inspection apparatus main body moving along the rail laid on the pipe in the vertical and horizontal directions, the rail in the narrow boiler is required. It takes a lot of time to install In addition, the method of using a pantograph for up and down movement of the optical inspection means is difficult to insert the optical inspection means deep into the heat exchanger tube group vertically staggered,
Insufficient inspection of lower tube. In addition, the method of using traverse to move the optical inspection means in the horizontal direction,
The optical inspection means could not sufficiently follow the curvature of the heat exchanger tube,
Inspection accuracy may be reduced.

On the other hand, in an apparatus in which two adjacent rows of tubes to be inspected in a group of steel tubes are vertically aligned, and the optical inspection means attached to the flexible arm is inspected while moving vertically, a flexible arm is used. Since the flexible arm is lowered by its own weight, it is difficult to insert the flexible arm deep into the group of steel pipes arranged in a staggered manner in the vertical direction, and there has been a problem that the inspection of the lower pipe cannot be performed sufficiently.

An object of the present invention is to provide an auxiliary work for inspection such as laying of rails even if the heat exchanger tubes are staggered in the vertical direction, and even if the heat exchanger tubes are curved. It is an object of the present invention to provide a pipe inspection apparatus capable of sufficiently inspecting the degree of thinning of a lower pipe without performing the same.

[0008]

SUMMARY OF THE INVENTION The object of the present invention is to provide a first moving means for moving the uppermost tube in a heat exchanger tube group arranged horizontally in a trajectory and moving one end thereof, A manipulator rotatably connected to the first moving means, and the other end moving along the tube to be inspected, a second moving means moving on the manipulator, and mounted on the second moving means,
The problem is solved by a pipe inspection apparatus including nondestructive inspection means for nondestructively inspecting a pipe.

Further, the pipe inspection apparatus of the present invention has a display means for outputting and displaying the position inspected by the nondestructive inspection means based on the position information of the first moving means and the second moving means.
Alternatively, if a configuration is provided having storage means for storing the position information inspected by the nondestructive inspection means, the inspection result can be easily recognized.

The non-destructive inspection means mounted on the second moving means of the pipe inspection apparatus of the present invention for non-destructively inspecting the pipe includes an optical sensor for directly inspecting the pipe, an ultrasonic sensor, or a radiation (X). Various sensors such as a sensor such as a line, a gamma ray, and a neutron beam) or an optical sensor for indirectly inspecting reflected light from a tube via a mirror or the like can be used. In particular,
The use of indirectly inspecting sensors can be used to advantage when the tube is located in a tight space.

Further, the first moving means is provided with one or more drive wheels which move along the uppermost tube in the heat exchanger tube group, and when each drive wheel is independently suspended, the uppermost tube is Even if is curved, the driving force of the drive wheels can be reliably transmitted to the uppermost pipe, and the first moving means can move smoothly.

The present invention is applicable not only to heat transfer tubes disposed in a boiler or a refuse incineration plant, but also to a heat exchanger such as an air conditioner.

[0013]

According to the above construction, the nondestructive inspection means is moved by the first moving means which moves with the uppermost pipe as a rail via the second moving means and the manipulator. There is no need to lay rails on existing pipes.

Since the manipulator is rotatably connected to the first moving means, the non-destructive inspection means mounted on the second moving means can be extended deeply into the heat exchanger tube banks vertically staggered. Can be inserted. Therefore, the problem that the lower pipe cannot be sufficiently inspected can be solved.

[0015] Since the second moving means equipped with the non-destructive inspection means moves along the pipe to be inspected,
Even if the tube to be inspected is curved, the nondestructive inspection means can follow the tube to be inspected, so that the inspection accuracy does not decrease.

[0016]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a tube inspection apparatus according to an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a front view for explaining the overall configuration of the present inspection apparatus, FIG. 2 is a view taken on line AA of FIG. 1 for explaining the first moving means in detail, and FIG. 3 is a drive moving along the uppermost pipe. B- of FIG. 1 illustrating the independent suspension method of the wheel.
FIG. 4 is a side view of a drive unit of the manipulator connected to the first moving means, FIG. 5 is a view of a longitudinal section of the second moving means, and FIG. FIG. 7 is a view taken along line C of FIG.
FIG.

The heat exchanger tube group 1 is disposed in a high-temperature gas flow path from a furnace surrounded on all sides by heat transfer walls, and FIG. 2 indicates the longitudinal direction of the tube.

As shown in FIGS. 1 and 2, the first moving means 2 which moves along the uppermost tube 1a of the heat exchanger tube group 1 staggered in the vertical direction applies a driving force of a motor 3a to a pulley. 3b, a sensor 5a is provided for transmitting to one of the four driving wheels 4 and moving, and measuring a moving distance in the tube axis direction and a sensor 5b for measuring a moving distance in the vertical direction, and as shown in FIG. A stand 8 is provided for connecting one end of the manipulator 6 rotatably via a shaft 7. The manipulator 6 is a motor 3 disposed on a stand 8 on the first moving means 2.
c at one end thereof and an opening 2 provided in the first moving means 2.
a and extends in the direction of the tube to be inspected 1a. here,
As shown in FIG. 3, even if the uppermost tube 1 a is curved, the four driving wheels 4 are surely in contact with the uppermost tube 1 a, and the rotating shafts of the driving wheels 4 are not rotated. 4a to spring 1
The slide type independent suspension structure pressed at 8 is adopted.

The second moving means 9 supporting the other end of the manipulator 6 includes a driven wheel 10 sliding on the tube to be inspected 1b and an optical camera 11, and a screw 17 and a slider 12 are driven by a motor 3c. , Can be moved up and down on the manipulator 6 to move deep inside the heat exchanger tube group 1. As shown in FIGS. 5 and 6, the second moving means 9 has a structure in which the slider 12 can be freely slid by the slider 12 so as to follow the curved tube 1b even if the tube 1b is curved. As shown in the cross-sectional view of FIG. 5, the follower wheel 10 has a rotating shaft 10a whose both ends are supported by a support member 12a integrated with the slider 12. Optical camera 11
a, 11b are arranged at the bottom of the manipulator 6.

A signal instructed from the remote controller 13 is controlled by the controller 14 and then transmitted to the motors 3a and 3c via the cable 15a.
Are driven and controlled.

On the other hand, the image captured by the optical camera 11 is transmitted through the cable 15b, and the moving distance signal in the tube axis direction measured by the sensor 5a and the moving distance signal in the vertical direction measured by the sensor 5b are transmitted through the cable 15c. The information is transmitted and displayed on the monitor 16.

In the above configuration, each heat transfer tube of the heat exchanger tube group 1 is filled in a limited space, and when the outer surface is inspected using the tube inspection device of the present invention, The procedure is as follows.

First, when inserting the tube inspection device of the present invention into the heat exchanger tube group 1, the second moving means 9 of the tube inspection device is located at the uppermost portion of the manipulator 6.
The manipulator 6 is moved to a position where it does not interfere with the furnace wall, and the device is pendulum-operated so as to make the device the center of rotation and inserted between the staggered tubes.

Next, the first moving means 2 is connected to the uppermost tube 1a.
Set to. Then, the inspector supports the upper end of the manipulator 6 by hand, finely moves the motor 3c by the remote controller 13, moves the second moving means 9 to the target position of the tube to be inspected 1b, and covers the follower wheel 10. A ring is attached to the inspection tube 1b. At this time, the vertical moving distance of the second moving means 9 is measured by the sensor 5b and displayed and recorded on the monitor 16.

In this state, the remote controller 13 sends the control device 1
4 sends a signal for controlling the motor 3a to move the first moving means 2 in the tube axis direction of the uppermost tube 1a. Then, the moving distance is measured by the sensor 5a and is displayed and recorded on the monitor 16. Here, the first moving means 2 has four driving wheels 4.
, The driving force of the motor 3a is reliably transmitted to the uppermost pipe 1a even if the uppermost pipe 1a is curved, so that smooth movement is possible.

Then, the second moving means 9 supported by one end of the manipulator 6 rotatably connected to the first moving means 2 is slid and moved to the inspection tube 1b, and the mounted optical camera 11 The appearance state of the inspected tube 1b observed in the above is displayed and recorded on the monitor 16, thereby inspecting the state of wall thinning on the tube surface. When inspecting the heat exchanger tubes arranged at the corners in the furnace, replace the manipulator 6 with a shorter one and perform the inspection.

It is also possible to mount a plurality of cameras on the second moving means 9 to observe a wide area. For example, if an optical camera 11b is mounted in addition to the optical camera 11a as shown in FIG. The back side of the tube 1c can be inspected. As shown in FIG. 7 which is a partially enlarged view of FIG. 1, the areas indicated by spots can be observed by the optical cameras 11a and 11b, respectively, and the area indicated by the lattice pattern can be observed by moving the manipulator 6 to the position indicated by the dotted line. , The entire circumference of the tube can be observed by moving the set sequentially.

In the above, the inspection example of the heat exchanger tube groups 1 vertically arranged in a staggered manner has been described. Inspection can be performed in the same manner as in the exchanger tube group 1.

Further, the method of feeding the second moving means 9 by a wire or a belt does not cause any problem.

Further, instead of directly observing the inspected tube 1b with the optical cameras 11a and 11b, as shown in FIG. 8, the image of the inspected tube 1b is refracted by the mirror 19 and indirectly reflected by the optical cameras 11a and 11b. Observation is also possible, so that the distance between the optical inspection means and the tube to be inspected can be increased even in a narrow portion.

In the above embodiment, the method of mounting the optical cameras 11a and 11b on the second moving means 9 and nondestructively inspecting the appearance of the heat exchanger tube has been described. As shown in FIG. 9, it is also possible to mount an ultrasonic sensor 20 on the second moving means 9 and measure the wall thickness of the heat exchanger tube as shown in a vertical sectional view of the second moving means 9 in FIG. .

In detail, as shown in FIGS. 10 and 11, a method of measuring a wall thickness using an ultrasonic wave is generally known, but an ultrasonic sensor 20 is applied to the outer surface of a tube 1b to be inspected, 21 is transmitted to the inspected tube 1b.
A part of the transmitted ultrasonic wave 21 is reflected on the surface of the inspection tube 1b, and the reflected wave S is detected by the ultrasonic measuring device 22. The remaining ultrasonic waves not reflected on the surface of the inspection tube 1b propagate through the material of the inspection tube 1b and are reflected on the inner surface. The reflected wave B is detected by the ultrasonic measuring device 22. The time difference Δt between the detected reflected wave S and the detected reflected wave B is the test tube 1
The thickness d is calculated by the following equation, corresponding to the thickness b. d = △
t · c / 2 where c is a known speed of sound propagating through the material of the tube to be inspected 1b.

In this way, the inspection can be performed up to the lower stage of the heat exchanger tube group 1 in a staggered arrangement, the installation of rails and the like can be omitted, the cost can be reduced, and the inspection device follows the curve of the tube, so that the inspection can be performed. Accuracy can be improved.

[0034]

According to the present invention, it is possible to inspect even the tubes arranged on the lower side of the staggered heat exchanger tube group, which could not be observed conventionally. In addition, since the pipe inspection device moves with the uppermost pipe as a track, installation of rails and the like can be omitted, and costs can be reduced. In addition, since the inspection device follows the curve of the tube, the inspection accuracy can be improved.

[Brief description of the drawings]

FIG. 1 is an overall configuration diagram of a pipe inspection device according to an embodiment of the present invention.

FIG. 2 shows the first moving means in detail AA in FIG.
FIG.

FIG. 3 is a BB diagram of FIG. 1 illustrating an independent suspension method of the drive wheels.
FIG.

FIG. 4 is a side view of the manipulator driving unit of FIG. 1;

FIG. 5 is a view of a longitudinal section of the second moving means in FIG. 1;

FIG. 6 is a view taken along line CC of FIG. 5;

FIG. 7 is a partially enlarged view of FIG. 1;

FIG. 8 is a view for explaining a method of increasing the distance between the optical camera and the tube to be inspected.

FIG. 9 is a schematic view showing another embodiment of the present invention and illustrating a method of measuring a wall thickness by ultrasonic waves.

FIG. 10 is a diagram illustrating a propagation path of an ultrasonic wave in a test tube.

FIG. 11 is a diagram illustrating a detection result of a reflected wave in which a vertical axis represents a reflected wave and a horizontal axis represents time.

[Explanation of symbols]

REFERENCE SIGNS LIST 1 heat exchanger tube group 1a uppermost tube 1b, 1c inspected tube 2 first moving means 3a, 3c motor 3b pulley 4 drive wheel 5a, 5b
Sensor 6 Manipulator 7 Axis 8 Stand 9 Second moving means 10 Follower wheel 10a Follower wheel rotation axis 11a, b, c Optical camera 12 Slider 13 Remote controller 14 Control device 15a, 15b, 15c Cable 16 Monitor 17 Screw 18 Spring 19 Mirror 20 Ultrasonic sensor 21 Ultrasonic wave 22 Ultrasonic measuring instrument

Continued on the front page F-term (reference) 2F065 AA30 AA51 BB08 FF04 JJ03 JJ05 JJ19 JJ26 LL12 MM24 PP02 QQ23 SS12 UU06 2F067 AA27 BB06 CC06 HH04 HH05 HH07 LL16 NN10 SS12 2F069 AA02 GG04 MM04 QQ07 2G051 AA90 AB20 AC16 CA04 CB01 EA14

Claims (4)

[Claims] 1. A first moving means for moving the uppermost tube in a heat exchanger tube bank arranged horizontally in a multistage manner as a trajectory;
One end is rotatably connected to the first moving means, and the other end moves along the tube to be inspected, the second moving means moving on the manipulator, and the second moving means. Non-destructive inspection means for non-destructively inspecting a pipe mounted on the pipe. 2. A display means for outputting and displaying the position information inspected by the nondestructive inspection means based on the position information of the first moving means and the second moving means, and / or the nondestructive inspection means. 2. The tube inspection apparatus according to claim 1, further comprising storage means for storing information on a position under inspection. 3. The non-destructive inspection means mounted on the second moving means and non-destructively inspecting the pipe is a sensor for directly inspecting the pipe or a sensor for indirectly inspecting the reflected light of the pipe. 2. The tube inspection apparatus according to claim 1, wherein: 4. The first moving means is provided with one or more drive wheels which move along the uppermost tube in the heat exchanger tube group, and each drive wheel is independently suspended. The pipe inspection apparatus according to claim 1, wherein: