JP7787474B2 - Pipe cutting test system and pipe cutting test method - Google Patents

Description

The present disclosure relates to a pipe cutting test system and a pipe cutting test method.

Technologies are known for protecting underground pipelines from being cut by pavement cutters and the like. For example, Patent Document 1 discloses a cable protection tube member that is inserted into an existing pipe with a cable laid inside.

Evaluation methods for assessing the cut resistance of pipelines are known. In one example of an evaluation method, the pipeline is buried underground. The pipeline is cut along with the soil using a pavement cutter or similar tool that approaches from a direction intersecting the axial direction of the pipeline. The worker subjectively evaluates the cut resistance of the pipeline based on the resistance to the pavement cutter, the movement of the pavement cutter, etc.

Japanese Patent Application Laid-Open No. 2015-192559

The above evaluation method allows the soil and other environments to be simulated to match the environment in which the pipeline will actually be buried. However, because the pipeline is buried underground, it was difficult to accurately measure the time required for the pipeline to be severed.

The present disclosure therefore aims to provide a pipeline cutting test system and a pipeline cutting test method that can accurately measure the time required for a pipeline to be cut.

In one embodiment, a pipeline cutting test system includes a cutting device that cuts a pipe that houses a cable, a first sensor that is provided on the pipe and transmits a first signal indicating a first time when the cutting device contacts the pipe, a second sensor that is provided on the cable and transmits a second signal indicating a second time when the cutting device contacts the cable, and a control device that receives the first signal and the second signal and calculates the time difference between the first time and the second time.

One embodiment of a pipeline cutting test method is a pipeline cutting test method that performs a pipeline cutting test in which a cutting device cuts a pipe that houses a cable, and includes the steps of detecting a first time when the cutting device contacts the pipe, detecting a second time when the cutting device contacts the cable, and calculating the time difference between the first time and the second time.

The pipeline cutting test system or pipeline cutting test method disclosed herein can accurately measure the time required for a pipeline to be cut.

1 is a perspective cross-sectional view illustrating an example of a pipeline disconnection test system according to an embodiment of the present disclosure. FIG. 2 is a plan view of the pipe disconnection testing system shown in FIG. 1 . FIG. 2 is a perspective view of the tube shown in FIG. 1 and its vicinity. FIG. 1 is an exploded view of the depth adjustment device and tube. 10 is a flowchart illustrating an example of pre-processing in a pipe disconnection test method. 1 is a flowchart illustrating an example of a process of a pipeline cutting test in a pipeline cutting test method.

Below, a pipeline disconnection testing system according to one embodiment of the present disclosure will be described with reference to the drawings.

Figure 1 is a perspective cross-sectional view of a pipe disconnection testing system 100 according to one embodiment of the present disclosure. Figure 2 is a plan view of the pipe disconnection testing system 100 shown in Figure 1. Figure 3 is a perspective view of a pipe 200 and its vicinity shown in Figure 1.

The pipe cutoff test system 100 performs a pipe cutoff test on a pipe 200 containing a cable 210. The pipe cutoff test system 100 may be installed underground or above ground. The pipe 200 may be a prototype or an actual pipe. The cable 210 may be a communication cable, a power cable, etc.

The outside of the pipe 200 may be covered with a protective member. A protective member may be inserted between the inside of the pipe 200 and the cable 210. The pipe 200 itself may be made of a protective member. The protective member may be provided only near the portion 200c to be cut by the cutting device 10. The protective member may be made of concrete, synthetic resin, etc.

The pipeline cutting test system 100 includes a cutting device 10, a first sensor 20, a second sensor 30, and a control device 40. The pipeline cutting test system 100 may also include an imaging device 50 and a depth adjustment device 60.

For example, a first storage space 310, a second storage space 320, and a soil section 400 located between the first storage space 310 and the second storage space 320 may be provided underground. The first storage space 310 and the second storage space 320 may be U-shaped trenches. When the pipeline disconnection test system 100 is installed in a test environment, at least the soil section 400 may simulate the soil environment in which the pipe 200 will actually be buried. This soil environment may be composed of, for example, a surface layer such as asphalt, a roadbed such as crushed stone located below the surface layer, and a road surface such as soil located below the roadbed.

The pipeline cutting test system 100 may be installed in the first storage space 310, the second storage space 320, and the soil section 400. The control device 40 and the depth adjustment device 60 may be installed in the first storage space 310. The imaging device 50 may be installed in the second storage space 320. The cutting device 10 may be installed in the soil section 400. The first sensor 20, the second sensor 30, and the pipe 200 may be installed throughout the first storage space 310, the soil section 400, and the second storage space 320.

Referring to FIG. 3, the cutting device 10 cuts the pipe 200 containing the cable 210. Referring to FIG. 1, the cutting device 10 may be a pavement cutter. The cutting device 10 may have a disc-shaped blade that rotates around its axis. The cutting device 10 may be movable in the plane of the blade while rotating the blade. The cutting device 10 may be a hand-pushed type.

The first sensor 20 is provided on the pipe 200. The first sensor 20 may be attached to the outer or inner surface of the pipe 200, or may be embedded in the pipe 200. The first sensor 20 may extend along the axial direction of the pipe 200. The first sensor 20 may be an optical core wire. The first sensor 20 may be connected to the control device 40 described below. A predetermined signal may be sent to the first sensor 20. The first sensor 20 may break when the cutting device 10 comes into contact with the pipe 200 at a first time.

The second sensor 30 is provided on the cable 210. The second sensor 30 may be a core wire within the cable 210. The second sensor 30 may be an optical core wire. The second sensor 30 may be connected to the control device 40. A predetermined signal may flow to the second sensor 30. The second sensor 30 may be disconnected when the cutting device 10 contacts the cable 210 at the second time. The second sensor 30 may be disconnected when the cutting device 10 cuts the cable 210.

A first sensor 20 and a second sensor 30 may be connected to the control device 40. The control device 40 may detect that the cutting device 10 has contacted the first sensor 20 at a first time by detecting that the signal from the first sensor 20 has been interrupted. The control device 40 may detect that the cutting device 10 has contacted the second sensor 30 at a second time by detecting that the signal from the second sensor 30 has been interrupted. In other words, the control device 40 receives a first signal from the first sensor 20 indicating the first time that the cutting device 10 contacted the pipe 200, and receives a second signal from the second sensor 30 indicating the second time that the cutting device 10 contacted the cable 210.

The control device 40 may calculate the time difference dt between the first time and the second time. The control device 40 may display the first time, the second time, or the time difference dt on a screen or the like. The control device 40 may determine whether the pipe 200 has sufficient cut-off resistance based on the time difference dt. For example, the control device 40 may determine that the pipe 200 has sufficient cut-off resistance if the time difference dt is equal to or greater than a threshold value (e.g., 10 minutes). The control device 40 may display the determination result on a screen or the like.

The camera device 50 may photograph the portion 200c of the pipe 200 that is cut by the cutting device 10 and the vicinity thereof. This configuration makes it possible to analyze the behavior of the pipe 200, protective member, cable 210, etc. when the cutting device 10 is in contact with the pipe 200. The camera device 50 may photograph the cut surfaces of the pipe 200 and cable 210 and the vicinity thereof. The camera device 50 may photograph sparks that occur when the cutting device 10 cuts the pipe 200. The camera device 50 may capture video or still images.

If the imaging device 50 detects sudden damage to the protective member or large movement of the pipe 200 or cable 210, it may determine that an abnormality has occurred and notify the worker. The imaging device 50 may be connected to the control device 40, and the control device 40 may determine that an abnormality has occurred and notify the worker.

There may be no light source inside the tube 200. To accommodate such situations, the imaging device 50 may be a night vision camera, an infrared camera, etc.

The imaging device 50 may be fixed to a tripod. The height of the imaging device 50 may be adjustable. The height of the imaging device 50 may be remotely adjustable. The imaging device 50 may be installed near the pipe 200.

4 is an exploded view of the depth adjustment device 60 and the pipe 200. Referring to FIG. 1, the depth adjustment device 60 may adjust the depth d of the pipe 200 from the surface of the soil portion 400 when at least the portion 200c of the pipe 200 to be cut by the cutting device 10 is embedded in the soil portion 400. In FIG. 1, the height of the surface of the soil portion 400 filled with soil material may be equal to the height of the upper surfaces of the first storage space 310 and the second storage space 320. The depth adjustment device 60 may be provided within or near the soil portion 400. Referring to FIG. 1, two depth adjustment devices 60 may be provided side by side in the axial direction of the pipe 200. One, three or more depth adjustment devices 60 may be provided.

Referring to Figure 4, the depth adjustment device 60 may include two bolts 61 and a pair of fasteners 62.

The length of the bolt 61 may be designed based on the expected thickness of the soil in the soil section 400, the depth d of the pipe 200 from the surface of the soil section 400, etc. One end of the bolt 61 may be embedded or inserted into the first storage space 310 with the threaded portion 61t exposed. The spacing between the two bolts 61 may be designed to match the position of the through-hole 62h of the fastener 62 described below. A first nut 63 may be inserted into the bolt 61. The first nut 63 may allow the height of the fastener 62, i.e., the depth d of the pipe 200 from the surface of the soil section 400 that is clamped by the fastener 62, to be adjusted.

The fastener 62 may be composed of a curved portion 62c and a flat portion 62p connected to both ends of the curved portion 62c. The fastener 62 may be rectangular in plan view.

The curved portion 62c may have a semi-cylindrical shape. The shape of the curved portion 62c may match the shape of the tube 200. The tube 200 may be sandwiched between the two curved portions 62c.

The flat portion 62p may extend along a line connecting both ends of the curved portion 62c. A through hole 62h may be formed on the flat portion 62p opposite the curved portion 62c. The cross-sectional shape of the through hole 62h may match the cross-sectional shape of the bolt 61. The bolt 61 may be inserted into the through hole 62h. Then, the second nut 64 may be inserted onto the bolt 61, and the pair of fasteners 62 may be fixed by the first nut 63 and the second nut 64.

A pipeline disconnection test method according to one embodiment of the present disclosure will now be described. Figures 5 and 6 are flowcharts illustrating an example of a pipeline disconnection test method. The process shown in Figure 5 is so-called pre-processing that is performed before a pipeline disconnection test is performed. The process shown in Figure 6 illustrates the process of a pipeline disconnection test based on this pre-processing. The processes shown in Figures 5 and 6 may be performed by the pipeline disconnection test system 100.

The pre-processing will now be described with reference to Figure 5. In step S110, with reference to Figure 3, the first sensor 20 and the second sensor 30 are attached. The first sensor 20 may be attached to the outer surface of the pipe 200. In a situation where the cable 210 is a communication cable, the second sensor 30 may be a core wire within the cable 210. The second sensor 30, which is a separate component from the cable 210, may also be attached to the cable 210. The first sensor 20 and the second sensor 30 may be connected to the control device 40.

In step S120, the position of the pipe 200 is adjusted. Specifically, referring to FIG. 4, the height of the fasteners 62, i.e., the depth d of the pipe 200 from the surface of the soil portion 400 sandwiched between the fasteners 62, is adjusted by adjusting the height of the first nuts 63 inserted into the two bolts 61 embedded in the first storage space 310. The through-holes 60h in one of the pair of fasteners 62 are inserted onto the two bolts 61 with the curved portion 62c protruding from the flat portion 62p toward the bottom surface of the first storage space 310. The fasteners 62 abut against the first nuts 63. The pipe 200 is then positioned on top of the curved portion 62c. At this time, the axial position of the pipe 200 is adjusted by moving the pipe 200 axially relative to the curved portion 62c. Furthermore, the two bolts 61 are inserted into the through-hole 60h of the other of the pair of fasteners 62, with the curved portion 62c protruding from the flat portion 62p to the side opposite the bottom surface of the first accommodation space 310. The pipe 200 is sandwiched between the two curved portions 62c. Then, a second nut 64 is inserted into the bolt 61, and the pair of fasteners 62 are fixed by the first nut 63 and the second nut 64.

In step S130, a protective member is attached. The outside of the pipe 200 may be covered with a protective member. A protective member may be inserted between the inside of the pipe 200 and the cable 210. The protective member may be provided only near the portion 200c to be cut by the cutting device 10. By providing the protective member only near the portion 200c to be cut by the cutting device 10, the cost, time, etc. of the pipe cutting test may be reduced. If the pipe 200 itself is made of a protective member, step S130 may be omitted.

In step S140, the soil section 400 is filled with soil material. Specifically, the soil section 400 may first be filled with soil to form a road body. Next, crushed stone may be filled into the soil section 400 to form a roadbed. Furthermore, the soil section 400 may be filled with asphalt, cement concrete, etc. to form a surface layer. The surface height of the formed surface layer may be equal to the height of the upper surfaces of the first storage space 310 and the second storage space 320. By filling only the soil section 400 with soil material and not substantially filling the first storage space 310 or the second storage space 320 with soil material, the environment required for pipeline disconnection testing can be efficiently realized.

In step S150, the position of the camera device 50 is adjusted. In a configuration in which the camera device 50 is fixed to a tripod, the height of the camera device 50 may be adjusted by opening and closing the tripod. The height of the camera device 50 may be adjusted remotely. A worker, machine, etc. may adjust the position of the camera device 50 from above the storage space 310, 320.

The process of the pipeline disconnection test will be explained below with reference to Figure 6. In step S210, with reference to Figure 1, the first sensor 20 and the second sensor 30 are activated. Specifically, a predetermined signal may be sent from the first sensor 20 and the second sensor 30 to the control device 40. In step S210, the imaging device 50 may also be activated.

In step S220, the cutting device 10 is started. Specifically, the disc-shaped blade of the cutting device 10 may rotate. The cutting device 10 may move toward the pipe 200. The cutting device 10 may also be moved by an operator.

In step S230, the first time when the cutting device 10 comes into contact with the pipe 200 is detected. Specifically, when the cutting device 10 comes into contact with the pipe 200 at the first time, the first sensor 20 is disconnected. Due to the disconnection, a predetermined signal that was flowing from the first sensor 20 to the control device 40 is interrupted. The control device 40 detects that the signal from the first sensor 20 has been interrupted. The control device 40 detects the first time from the content of the signal immediately before the interruption, the time of detection, etc.

Between step S230 and step S240, the pipe 200 may be cut. If the protective function of the protective member is high, it will take a long time for the cutting device 10 to cut the pipe 200. Note that if the protective function of the protective member is very high, the cutting device 10 may not be able to cut the pipe 200. In this case, step S230, which will be described later, is omitted.

In step S240, the second time when the cutting device 10 comes into contact with the cable 210 is detected. Specifically, when the cutting device 10 comes into contact with the cable 210 at the second time, the second sensor 30 is disconnected. Due to the disconnection, a predetermined signal flowing from the second sensor 30 to the control device 40 is interrupted. The control device 40 detects that the signal from the second sensor 30 has been interrupted. The control device 40 detects the second time from the content of the signal immediately before the interruption, the time of detection, etc. At this point, the cutting device 10 may stop.

In step S250, the time difference dt between the first time and the second time is calculated. The control device 40 may display the first time, the second time, or the time difference dt on a screen or the like. The control device 40 may determine whether the pipe 200 has sufficient cut-off resistance based on the time difference dt. For example, the control device 40 may determine that the pipe 200 has sufficient cut-off resistance if the time difference dt is greater than or equal to a threshold value (e.g., 10 minutes). If step S230 is omitted, the control device 40 may determine that the pipe 200 has sufficient cut-off resistance. The control device 40 may display the determination result on a screen or the like. An operator may determine whether the pipe 200 has sufficient cut-off resistance based on the time difference dt.

In step S260, the first sensor 20 and the second sensor 30 are shut down. In step S260, the imaging device 50 may also be shut down.

From steps S220 to S250, the camera device 50 may photograph the portion of the pipe 200 that is to be cut by the cutting device 10. If the camera device 50 detects sudden damage to the protective member or large movement of the pipe 200 or cable 210, it may determine that an abnormality has occurred and notify the worker. The worker may receive the notification and stop the pipeline cutting test. The camera device 50 may determine the cause of the abnormality and notify the worker. The worker may determine the cause of the abnormality based on the notification from the camera device 50 or the video or still images. The worker may determine that an abnormality has occurred and may resolve the problem.

This shows the post-processing that is performed after the pipeline cutting test processing is completed.

The soil material in the soil section 400 may be removed. The first nut 63 and the second nut 64 may then be loosened. The pipe 200 may be removed from the depth adjustment device 60 in order to replace it with a new pipe.

For the next test, the processes shown in Figures 5 and 6 may be repeated.

The following notes are further disclosed regarding the above embodiments.

(Additional note 1)
a cutting device for cutting the tube containing the cable;
a first sensor mounted on the tube for transmitting a first signal indicative of a first time when the cutting device contacts the tube;
a second sensor disposed on the cable for transmitting a second signal indicative of a second time when the cutting device contacts the cable;
a control device that receives the first signal and the second signal and calculates a time difference between the first time and the second time;
A pipe disconnection test system comprising:
(Additional note 2)
Item 2. The pipe cut testing system according to item 1, further comprising an imaging device that images the portion of the pipe that is cut by the cutting device.
(Additional note 3)
3. The pipe cutting test system according to claim 1 or 2, further comprising a depth adjustment device that adjusts the depth of the pipe from the surface of the soil when at least the portion of the pipe to be cut by the cutting device is buried in the soil.
(Additional note 4)
The pipeline cutoff test system according to any one of appendix 1 to 3, wherein the control device determines whether the pipe has sufficient cutoff resistance based on the time difference.
(Additional note 5)
A pipe cutting test method for performing a pipe cutting test in which a cutting device cuts a pipe that accommodates a cable,
detecting a first time when the cutting device contacts the tube;
detecting a second time when the cutting device contacts the cable;
calculating a time difference between the first time and the second time;
A pipe disconnection test method, comprising:
(Additional note 6)
further comprising the step of photographing the portion of the tube cut by the cutting device.
6. The method for testing a pipe cut according to claim 5.
(Supplementary Note 7)
The method for testing a pipe line cutoff according to claim 5 or 6, further comprising the step of determining whether the pipe has sufficient cutoff resistance based on the time difference.

The above-described embodiments have been described as representative examples, but it will be apparent to those skilled in the art that many modifications and substitutions are possible within the spirit and scope of the present disclosure. Therefore, the present invention should not be construed as being limited by the above-described embodiments, and various modifications and alterations are possible without departing from the scope of the claims.

REFERENCE SIGNS LIST 10 Cutting device 20 First sensor 30 Second sensor 40 Control device 50 Photography device 60 Depth adjustment device 60h Through hole 61 Bolt 61t Threaded portion 62 Fastener 62c Curved portion 62h Through hole 62p Flat portion 100 Pipe cutting test system 200 Pipe 200c Part 210 Cable 310 First storage space 320 Second storage space 400 Soil portion d Depth dt Time difference

Claims (7)

a cutting device for cutting the tube containing the cable;
a first sensor mounted on the tube for transmitting a first signal indicative of a first time when the cutting device contacts the tube;
a second sensor disposed on the cable for transmitting a second signal indicative of a second time when the cutting device contacts the cable;
a control device that receives the first signal and the second signal and calculates a time difference between the first time and the second time;
A pipe disconnection test system comprising: The pipe cutting test system of claim 1 further comprises an imaging device that images the portion of the pipe being cut by the cutting device. A pipe cutting test system as described in claim 1 or 2, further comprising a depth adjustment device that adjusts the depth of the pipe from the surface of the soil when at least the portion of the pipe to be cut by the cutting device is buried in the soil. A pipe cutting test system as described in claim 1 or 2, wherein the control device determines whether the pipe has sufficient cut-resistance based on the time difference. A pipe cutting test method for performing a pipe cutting test in which a cutting device cuts a pipe that accommodates a cable,
detecting a first time when the cutting device contacts the tube;
detecting a second time when the cutting device contacts the cable;
calculating a time difference between the first time and the second time;
A pipe disconnection test method, comprising: further comprising the step of photographing the portion of the tube cut by the cutting device.
The method for testing a pipe line cut according to claim 5. The method for testing a pipe line cutoff according to claim 5 or 6, further comprising the step of determining whether the pipe has sufficient cutoff resistance based on the time difference.