JPH0359746B2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to an apparatus for coating the inner surface of small diameter pipes, particularly those with a diameter of approximately 650 mm or less, which prevents humans from entering the pipe, and approximately 1.5 times the diameter. This invention relates to an inner surface coating device that is capable of powder coating a three-dimensional, small-diameter bent pipe in which a plurality of elbows are connected.

[Prior Art] In piping work for laying pipes for water, sewage, oil, seawater, etc., single pipes whose inner surfaces have been painted in advance at a factory are joined by welding on site. In order to protect the inner surface and surrounding area of the pipe joints that have been welded on-site, the remaining welding slag, burnt paint film caused by welding heat, rust, etc. must be cleaned and removed, and then the specified film thickness and width must be met. It is necessary to apply an anti-corrosion coating. However, in the case of small-diameter pipes with a diameter of approximately 650 mm or less, it is almost impossible for humans to enter the pipe to perform tasks such as cleaning, removing, and painting. A pipe interior coating device has been proposed.

For example, as a coating device like this,
-118465 and Japanese Patent Application No. 58-58738. However, these conventional devices are generally intended for straight pipes, and are not intended for three-dimensionally curved pipes including elbows with a small radius of curvature as described above.

[Problem that the invention seeks to solve]

In other words, in the conventional device described above, the means for inserting the coating device into the pipe is inputted through a pipe connected to the rear end of the device, so it is not possible to pass through the elbow portion, and the insertion distance is limited to a short distance. It had been. Furthermore, since the coating device is relatively long compared to the diameter of the applicable pipe, there are other problems such as the fact that it is impossible to pass through the elbow of the coating device itself. In addition, conventional equipment used a drying type coating that cures at room temperature, so it is suitable for pipelines that handle highly corrosive gases and liquids, such as those containing H ₂ S and CO ₂ . There were problems with durability.
Therefore, there has been a demand for a small-diameter pipe inner surface coating apparatus that can perform powder coating with high chemical stability even on small-diameter curved pipes with a three-dimensional shape as described above.

[Means for solving problems]

The small-diameter pipe inner surface coating apparatus according to the present invention includes a link mechanism-type tube inner surface self-propelled vehicle 1 in which a drive wheel 13 is attached to a link mechanism 12 that can be freely expanded and contracted in the radial direction, and an electric power and compressor that is supplied to the self-propelled vehicle from outside the pipe. Transport vehicles 2 and 4 are equipped with a cable 9 for supplying air and a cleaner for cleaning the inner surface of the tube or a powder coating machine for painting the inner surface of the tube.
a connecting means for removably connecting the guided vehicle to the self-propelled vehicle to move the guided vehicle together with the self-propelled vehicle; and a tubular body local heating device that heats a portion of the tubular body from the outside; The connecting means is characterized in that it is constituted by a flexible air hose 7 for sending compressed air for driving the grinder or powder coating machine from the self-propelled vehicle.

[Effect]

In the present invention, the cleaning and painting operations are performed by a combination of an in-pipe self-propelled vehicle, a grinder transport vehicle, and a combination of an in-pipe self-propelled vehicle, a powder coating machine transport vehicle, and a pipe body local heating device. The self-propelled vehicle and the conveyed vehicle are connected by a flexible air hose via an air connector, making it easy for the self-propelled vehicle and the conveyed vehicle to pass through the elbow. However, in order to allow self-propelled vehicles and transport vehicles to pass through the elbow,
The length of the vehicle body is made as short as possible. Also,
If the output of one self-propelled vehicle is insufficient, two or more vehicles may be connected using a combined flexible hose having electrical and air connectors. On the other hand, the cleaning machine and powder coating machine mounted on the transport vehicle are driven by compressed air transported from the self-propelled vehicle via a flexible air hose. Further, the compressed air for driving and the electric power for driving the self-propelled vehicle are supplied from a cable connected to the self-propelled vehicle from outside the pipe.

In the present invention, since the self-propelled vehicle has a vehicle body structure in which the drive wheels are attached to a link mechanism that can be expanded and contracted according to the inner diameter of the pipe, it can freely pass through even the elbow portions having a small radius of curvature as described above. In addition, during painting, the tube is partially heated by an electromagnetic induction heating device that can move freely over the outside of the tube, and the powder paint sprayed onto the heated inner surface of the tube is immediately heated and fused. ing.

〔Example〕

Hereinafter, one embodiment of the present invention will be described with reference to the drawings.
Fig. 1 is an explanatory diagram when carrying out the cleaning work on the inner surface of the pipe, Fig. 2 is an enlarged front view of the self-propelled vehicle in the pipe, Fig. 3 is an explanatory diagram of the link mechanism of the self-propelled vehicle in the pipe, and Fig. 4 is FIG. 5 is a front view of the cleaning machine transport vehicle, FIG. 5 is an explanatory diagram when painting the inner surface of a tube, and FIG. 6 is a front view of the powder coating machine transport vehicle. The illustrated embodiment shows a case where two self-propelled vehicles in the area are connected. In the figure, reference numeral 1 denotes a link mechanism type self-propelled tube vehicle, and each of the self-propelled tube vehicles 1 is connected to each other by a combination type flexible air hose 7 having electrical and air connectors 71 and 72 at both ends. 2 is air connector 31,3
2 at both ends of the flexible air hose 3,
This is a sanding machine transport vehicle connected to an in-service self-propelled vehicle 1.
Similarly, 4 is a powder coating machine transport vehicle in which a powder paint supply device 5 is connected to an in-pipe self-propelled vehicle 1. Further, the powder coating machine transport vehicle 4 and the powder coating supply device 5 are connected by a flexible blower pipe 6 having a coupling ring 61 at its tip.

The in-pipe self-propelled vehicle 1 has a traveling drive device 11 consisting of a motor and a speed reduction device in the center, and a link mechanism 12 consisting of a front link 12a, a rear link 12b, and a guide link 12c in the main body case of the drive device 11. One pair is arranged on the upper and lower sides, and four drive wheels 13 running on the inner surface of the tube body P are pivotally supported between each pair of opposing links. The necessary pressing force between the drive wheel 13 and the inner surface of the tube body is ensured by a spring 14 that always biases the link mechanism 12 in the direction of expansion. The drive wheels 13 are made of rubber rollers, for example, and are all-wheel driven by the travel drive device 11 via belts or chains 11a, 11b attached to the front link 12a and guide link 12c, respectively.

As clearly shown in FIG. 3, the link mechanism 12 is connected through a slide guide hole 12e so that the pivot point 12d of the rear link 12b with the traveling drive device main body case moves slightly to the front side, and the auxiliary link 12f The intermediate portion of the rear link 12c and the drive device main body case are connected by this. With this configuration, it is possible to pass through the elbow even if the elbow is not completely concentric and has a somewhat flat curve.

Reference numeral 15 denotes a guide wheel provided to stabilize the self-propelled vehicle 1 in the pipe, and the guide wheel 15 is pivotally supported by a guide frame 16 disposed laterally with respect to the link mechanism 12 in the vertical direction. Also, guide frame 1
6 is provided with a radioisotope 8 for detecting positions to be cleaned and painted, as will be described later.

Next, the sanding machine transport vehicle 2 has a rotating brush 22 connected to a sanding machine air motor 21 in the center, and a fixing ring 23 is attached to the outer periphery of the air motor 21.
and a cylindrical body 25 having a slide ring 24 is fixed. Further, around the cylinder body 25, three sets of cross link mechanisms 26 consisting of links 26a and 26b cross-connected in an X shape are arranged at equal angles, and the base ends of each link 26a and 26b are connected to fixing rings 23, respectively. and pivotally supported on the slide ring 24,
Further, a total of six rolling wheels 27 that roll on the inner surface of the tubular body P are pivotally supported at the outer ends of each of the links 26a and 26b. In addition, 28 is a slide ring 24
This is a fixing bolt.

The rotating brush 22 includes a disk 22a attached to a rotating shaft 21a of an air motor 21 for a cleaner, and a torsion wire 22b planted on the peripheral edge of the disk 22a.
It is made up of.

The flexible air hose 3 that connects the in-pipe self-propelled vehicle 1 and the grinder transport vehicle 2 is for supplying compressed air, which is a power source, to the air motor 21 for the grinder from outside the pipe, and has air connectors 31 at both ends. ,32
have.

Furthermore, the flexible hose 7 that connects the two in-pipe self-propelled vehicles 1 is a combination type that can conduct both electricity and compressed air. Electrical and air connectors 71 and 72 are provided at both ends to communicate with the flexible air hose 3, respectively.

In the figure, 9 is a combined electric/air type cable that is inserted from the end of the tube, and the electric/air connector 91 at the tip.
It is connected to the last self-propelled vehicle 1 in the pipe.
Further, the base end of the cable 9 is connected to an external power source, a controller, and an air compressor (all not shown).

Next, a powder coating machine transport vehicle 4 shown in FIG. 5 has a body structure that is almost the same as the above-mentioned sanding machine transport vehicle 2, and therefore corresponding parts are given the same reference numerals and explanations are omitted. do.

This powder coating machine transport vehicle 4 has a powder coating supply device 5.
It has become common for people to carry the same items with them. The powder paint supply device 5 includes a blower tank 51 that stores synthetic resin powder paint such as epoxy or polybdenum, and has an ejector-type discharge mechanism 52 at the bottom;
It consists of front and rear support guides 53 that rotatably and movably support the inside of the tube body P. Each support guide 53 is formed by attaching an arm 53b having a roller 53a in a radial direction to a boss 53c so as to support the blower tank 51 substantially on the tube axis. The hollow shafts 54 provided on both sides of the blower tank 51 are supported by bearings (not shown) provided inside the boss 53c, and the blower tank 51 itself, which is formed with a low center of gravity, is always kept perpendicular to the ground. The hollow shaft 54 on the rear side is connected in communication with the flexible air hose 3 via the boss 53c, and the hollow shaft 54 on the front side is connected in communication with the flexible blower pipe 6 via the boss 53c. ing. Furthermore, the hollow shaft 54 on the rear side has a pressurizing pipe 55 and a nozzle pipe 56 that are connected in a T-shape, and the tip of one pressurizing pipe 55 communicates with the upper part of the inside of the blower tank 51. The tip of the other nozzle pipe 56 is partially enlarged in FIG.
An ejector-type discharge mechanism 52 is configured to face sideways the end of the discharge port 57 at the bottom of the blower tank 51. The discharge port 57 communicates with the hollow shaft 54 on the front side through a differential user pipe 58 provided in the orientation direction of the nozzle pipe 56. Therefore, the compressed air forced through the flexible air hose 3 is diverted through the hollow shaft 54 on the rear side, and a part of it enters the blower tank 51 via the pressure pipe 55, pressurizing the powder paint inside, while compressing the air. The remainder of the air is ejected from the tip of the nozzle pipe 56, and the powder paint is sucked through the discharge port 57 by the partial negative pressure generated by the wake and sent into the differential user pipe 58. The mixture of powder coating material and compressed air is further discharged from the differential user pipe 58, through the front hollow shaft 54 and the flexible blower pipe 6, and from the nozzle of the powder coating machine, which will be described later.

Next, the powder coating machine carrier 4 connected to the powder coating supply device 5 by the flexible blower pipe 6 is in communication with the casing 41 surrounding the cross link mechanism 26 and the flexible blower pipe 6. A rotating cylinder 42 is rotatably supported by the casing 41, and a front nozzle 43 and a rear nozzle 44 are connected to each other in the radial direction at the tip of the rotating cylinder 42.
It is made up of. Further, as shown in FIGS. 7 and 8, the rotating cylinder 42 is equipped with an impeller 46 so as to be rotated by compressed air that is forced into the casing 41 through an air hose 45, and this air hose 45 is connected to the flexible air hose 3. It is connected to an external compressor (not shown) in a separate line. The flexible blower pipe 6 is connected to the casing 41 via a coupling ring 61, and the base end of the rotary cylinder 42 is airtightly opposed to the tip of the flexible blower pipe 6 and is connected to the bearing 4.
7 and 48. A fluid regulator 49 is provided at the inner tip of the rotary cylinder 42 to smoothly distribute the powdered paint that has been pumped to the front and rear nozzles 43 and 44. The nozzles 43 and 44 are formed to be wide and flat as they go from the base end to the tip, and are set so as to cover a predetermined width in front and behind the welding beat B as the center, as can be seen from FIG. ing. This is because the powder coating material can be simultaneously sprayed over a predetermined width in front and behind the welding bead B by simply rotating the nozzle in that position without moving it back and forth. However,
The two-split nozzles 43 and 44 described above are used exclusively for curved pipes, and for straight pipes or similar pipes, a wide-mouth nozzle 50 with a wider discharge end is used as shown in FIG. It is also possible. In this case, a baffle plate 50a is provided inside to uniformly spray powder paint from the entire width of the discharge end.

Next, in this embodiment, the tube body local heating device 10 for thermally fusing the powder coating material to the inner surface of the tube is
As shown in the figure, it is shown as an electromagnetic induction type heating device. In the figure, 101 is an induction coil surrounding the tubular body P, and a support roller 103
The coil frame 102 is supported by an insulating coil frame 102 and is configured to move concentrically with the tube body P.
Note that 104 is a terminal connected to a power source (not shown).

Next, a case will be described in which powder coating is performed on the inner surface of a small-diameter pipe, that is, on a welded joint using the apparatus of the present invention configured as described above.

First, it is necessary to grind the relevant area prior to painting, so in this case, the grinder carrier 2 is connected to the in-pipe self-propelled vehicle 1 through the air connector 31 of the flexible air hose 3. In addition, if the target pipe P is a small-diameter pipe with a diameter of about 150 mm, one self-propelled vehicle 1 does not have sufficient running ability, so two self-propelled vehicles are required as shown in Figure 1. 1 are used by connecting them with a flexible hose 7.

From the end of the pipe, the vacuum cleaner transport vehicle 2, then the self-propelled vehicle 1 inside the pipe.
When the machine is manually inserted and the travel drive device 11 is started, the drive wheels 13 rotate and the self-propelled vehicle 1 moves deep into the pipe while pushing the cleaning machine carrier 2 through the flexible hose 3. go. In this case, it goes without saying that when the tube P is a straight tube, even if it is a curved tube as shown in FIG. 1, it can freely pass through the elbow portion thereof.

To detect the location to be polished and painted, a low-level radio isotope 8 installed on the self-propelled vehicle 1 in the area is used.
This can be determined by a position detector 81 built into the GM tube, which is placed on the outer surface of the tube as shown in FIGS. 12 and 13. In other words, if the position detector 81 is fixed on the outer surface of the tube body at a position B ^AL that is a certain distance L away from the position A to be polished or painted, the radio isotope 8 attached to the self-propelled vehicle 1 in the pipe will be located at the fixed distance L from the position A to be polished or painted. As it approaches position B ^AL ,
The GM tube begins to operate and the signal lamp 82 flashes. And detector 81 and radioisotope 8
When they match, the sensitivity is the highest and the signal lamp 82 blinks continuously, and as the distance increases, the signal lamp 82 changes from blinking to extinguishing. At this point of continuous flashing, the self-propelled vehicle 1 is stopped and the cleaning operation begins.

The cleaning work is carried out by activating the air motor 21 for the cleaning machine mounted on the cleaning machine transport vehicle 2, rotating the rotary brush 22, and moving the self-propelled vehicle 1 in the pipe back and forth by the required coating width. I'll pull over and do it. Twisted wire 22 of rotating brush 22 held coaxially with tube P
By the rotation of b and the back-and-forth movement of the self-propelled vehicle 1 in the pipe, welding slag, burnt coating, rust, etc. on the welded joint can be cleaned.

This cleaning work starts from the welded joint near the end of the pipe and continues to the innermost welded joint by repeatedly repeating the position detection and cleaning work.

After the above-mentioned grinding work is completed, the grinder carrier 2 is pulled out to the pipe body, and then the air compressor hose (not shown) is sent to the innermost welded joint, and the compressed air is directed toward the pipe end. It is gradually pulled out while being injected backwards to discharge and remove accumulated materials such as slag and paint film that have accumulated at the bottom of the pipe. Incidentally, the accumulated material may be sucked out with the hose of a large vacuum cleaner.

After all of the above-mentioned grinding and cleaning work is completed, the painting process begins. For the painting work, first, the sanding machine carrier 2 is removed, and the powder coating machine carrier 4 is connected to the in-pipe self-propelled vehicle 1 instead, and is sent into the pipe in the same manner as described above. Painting starts from the innermost welded joint. After detecting the position to be painted on the welded joint in the same manner as described above, the powder coating machine is transported to position C, which is a predetermined distance away from the weld bead B at the position toward the pipe end, as shown in Fig. 11. Car 4 is temporarily stopped.

Next, by moving the tubular body local heating device 10 over the weld bead B and energizing the induction coil 101, the area can be heated to a thermal fusion temperature suitable for powder coating in a short time. . Immediately after heating, the powder coating machine carrier 4 is moved from position C to B, and compressed air is supplied from a compressor (not shown) outside the pipe through the flexible air hose 3 and the air hose 45. The compressed air supplied through the air hose 45 is supplied to the powder coating machine transport vehicle 4.
The water is sent to an impeller 46 to rotate a rotary cylinder 42 to which nozzles 43 and 44 are attached. On the other hand, as mentioned above, the compressed air passing through the flexible air hose 3 is first sent to the powder paint supply device 5, and the powder paint stored in the blower tank 51 is continuously removed by a fixed amount by the ejector type discharge mechanism 52. Discharge. The discharged powder coating material subsequently passes through the flexible blower pipe 6 and the rotating tube 42, and is sprayed from rotating nozzles 43 and 44 toward the inner surface of the tube. As the nozzles 43 and 44 rotate, the powder paint is simultaneously sprayed over a predetermined width in the front and back around the weld bead B, and since this area is heated as described above, the sprayed powder paint is immediately thermally fused. A predetermined powder coating will be applied here.

Thereafter, the same procedure is repeated to apply powder coating to all welded joints.

〔Effect of the invention〕

As described in detail above, the present invention provides a link mechanism type in-tube self-propelled vehicle having a link mechanism that can be freely expanded and contracted in the radial direction, and a grinder transport vehicle that is removably connected to the self-propelled vehicle via a flexible air hose. And since the powder coating conveyor is driven inside a small-diameter pipe, even if the pipe body is a three-dimensional bent pipe with an elbow, it can be inserted deep into the pipe, and it can be inserted into a specified welded joint. This has the effect of making it possible to perform powder coating with high durability.

[Brief explanation of drawings]

Fig. 1 is an explanatory diagram when carrying out a cleaning work according to an embodiment of the present invention, Fig. 2 is an enlarged front view of a self-propelled vehicle within the jurisdiction, and Fig. 3 is an explanatory diagram of the link mechanism of the self-propelled vehicle within the jurisdiction. Figure 4 is a front view of the sanding machine transport vehicle, Figure 5 is a partially enlarged explanatory diagram when performing painting work, Figure 6 is a front view of the powder coating machine transport vehicle, and Figure 7 is powder coating. 8 is a front view of the rotation mechanism of the nozzle, FIG. 9 is an explanatory diagram showing another example of the nozzle, and FIG. 10 is an explanation of the tube local heating device. Figure 11 is an explanatory diagram of the powder coating work situation,
FIGS. 12a and 12b are a front view and a side view of the position detector, respectively, and FIG. 13 is an explanatory diagram of a method for detecting a position to be polished or painted. 1: Self-propelled vehicle within the jurisdiction, 2: Grinding machine carrier, 3: Flexible air hose, 4: Powder coating machine carrier, 1
0: Pipe body local heating device, 11: Traveling drive device, 1
2: Link mechanism, 31, 32: Air connector.

Claims (1)

[Scope of Claims] 1. A link mechanism-type self-propelled vehicle 1 with a drive wheel 13 attached to a link mechanism 12 that can be freely expanded and contracted in the radial direction, and supplying electric power and compressed air to the self-propelled vehicle from outside the tube. A cable 9, transport vehicles 2 and 4 equipped with a polisher for cleaning the inner surface of the tube or a powder coating machine for painting the inner surface of the tube, and the transport vehicle is removably connected to the self-propelled vehicle for the transportation. The connecting means includes a connecting means for moving the vehicle together with the self-propelled vehicle, and a tube local heating device for heating a part of the tube from the outside, and the connecting means is connected to compressed air for driving the grinder or powder coating machine. A small diameter pipe inner surface coating device comprising a flexible air hose 7 for sending air from the self-propelled vehicle.