Pipe

Abstract

To provide a pipe easy to lift and excellent in workability.SOLUTION: A pipe 1 includes a pipe body 10 and a mark provided on an outer surface of the pipe body 10, and the mark includes a first mark 11 provided at a gravity center position of the pipe 1 and at least one second mark 12 provided apart from the gravity center position.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a pipe. [Background technology]

[0002] BACKGROUND ART Conventionally, when a pipe is to be installed in, for example, an underground space, the pipe is hung down a vertical shaft for installation.

[0003] For example, Patent Document 1 discloses a method for rehabilitating existing pipes, which involves suspending a pipe down a vertical shaft, unwinding the cable from the upstream side to transport the pipe while controlling its flow speed, and then connecting the pipes one after the other at their destination. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2011-106537 Summary of the Invention [Problem to be solved by the invention]

[0005] However, when the shaft or underground space is narrow, or when the shaft has struts as construction elements, the pipe may be lifted using a single-point lift, and then lowered into the underground space by tilting the pipe to change the angle and avoid obstacles such as struts. Single-point lifting is generally performed by connecting a wire to the center of gravity of the pipe. In this case, if the position of the center of gravity of the pipe had to be checked and marked on-site each time, construction could be time-consuming.

[0006] Furthermore, in a vertical shaft or underground space, for example, it may be difficult to confirm the insertion depth when inserting a pipe into an existing pipe, for example.

[0007] The present invention has been made in consideration of the above circumstances, and has as its object to provide a pipe that is easy to lift and has excellent workability. [Means for solving the problem]

[0008] In order to solve the above problems, the present invention proposes the following means. (1) A pipe comprising a pipe body and a mark provided on the outer surface of the pipe body, the mark having a first mark provided at the center of gravity of the pipe and at least one second mark provided at a distance from the center of gravity. (2) The second marks are graduations provided at equal intervals along the length of the tube body. (3) The second mark is a mark provided at a position corresponding to the insertion amount of the pipe into another member to be connected. (4) The center of gravity is biased toward one of the two ends of the pipe body relative to a position that divides the pipe body into two equal parts in the longitudinal direction. (5) The pipe body has a recess provided at the center of gravity. (6) The pipe body has an anti-slip portion provided at the center of gravity. (7) At least one of the first mark and the second mark is provided over the entire circumferential circumference of the pipe body. [Effects of the Invention]

[0009] According to the present invention, a pipe can be provided that is easy to lift and has excellent workability. [Brief explanation of the drawings]

[0010] [Figure 1] FIG. 2 is a schematic side view of the pipe of the present embodiment. [Figure 2] FIG. 2 is a schematic side view of a single-side support pipe according to the present embodiment. [Figure 3] FIG. 1 is a schematic diagram of the pipe of this embodiment being lifted by single-point lifting. [Figure 4]1 is a schematic diagram showing a state in which a pipe according to the present embodiment is inserted into an existing pipe. [Figure 5] FIG. 10 is a schematic diagram of a pipe of a first modified example in a state where the pipe is lifted by two-point lifting. [Figure 6] FIG. 10 is a schematic diagram showing an example of a pipe according to a second modified example. [Figure 7] FIG. 10 is a schematic diagram showing an example of a pipe according to a second modified example. [Figure 8] FIG. 10 is a schematic diagram showing a state in which a pipe according to a second modified example is lifted by single-point lifting. DETAILED DESCRIPTION OF THE INVENTION

[0011] Hereinafter, an embodiment of a pipe 1 according to the present disclosure will be described with reference to FIGS.

[0012] FIG. 1 shows a side view of a pipe 1A of this embodiment. As shown in FIG. 1, the pipe 1 has a pipe body 10 and a mark provided on the outer surface of the pipe body 10 .

[0013] As shown in Fig. 1, the pipe body 10 of this embodiment is formed in a straight pipe shape. The pipe body 10 of this embodiment has a circular cross section, but the shape of the pipe body 10 is not limited to this. The shape of the pipe body 10 may also have a substantially circular cross section. The pipe body 10 does not have to have the same cross section shape and outer diameter along the axial direction, and may be, for example, a single-end straight pipe as shown in Fig. 2, or may be, for example, a single-end insertion reducer.

[0014] The pipe 1 may be a fixed length pipe. The size of the pipe 1 is not limited. The outer diameter of the pipe 1 may be, for example, 20 mm to 200 mm. The length of the pipe 1 may be, for example, 6000 mm or less, 4000 mm or less, or 2000 mm or less.

[0015] There is no limitation on the material of the pipe 1. The pipe 1 may be, for example, any one of a metal pipe, a ceramic pipe, a composite pipe, a resin pipe, a polyethylene pipe, a polyvinyl chloride pipe, and a polypropylene pipe.

[0016] As shown in FIG. 1 , the marks of this embodiment include a first mark 11 provided at the center of gravity of the pipe 1A and multiple second marks 12 provided at intervals from the center of gravity. The number of second marks 12 does not need to be multiple; for example, only one may be provided. In the illustrated example, the second marks 12 include multiple scales 12a provided at equal intervals along the length of the pipe body 10 and a mark 12b provided at a position corresponding to the insertion depth of the pipe 1 into another component to be connected. The second marks 12 may include only the scales 12a or only the mark 12b. The mark 12b is not limited to being provided at a position corresponding to the insertion depth of the pipe 1A into another component to be connected. For example, the mark 12b may be provided at a position indicating an area of ​​the outer surface of the pipe 1 that needs to be scraped when connecting the pipe 1A to an electrofusion joint.

[0017] For example, in FIG. 1 , the mark 12b is provided at one end of the pipe body. When the mark 12b is provided at a position corresponding to the insertion depth of the pipe 1A into the other component to be connected, the region R between the mark 12b and the second end 22, which is the end closest to the mark 12b among the two ends of the pipe (first end 21, second end 22), may be the region corresponding to the insertion depth of the pipe 1A into the other component to be connected. In this case, when inserting the second end 22 of the pipe 1A into, for example, a fitting, the installer may be able to determine whether the pipe 1A has been inserted into the fitting sufficiently by checking whether the pipe 1A is inserted into the fitting up to the position of the mark 12b. In the illustrated example, one mark 12b is provided at one end of the pipe body, but the number of marks 12b is not limited. Two marks 12b may be provided, for example, marks 12b may be provided at both ends of the pipe body.

[0018] For example, in FIG. 1, if mark 12b is provided at a position indicating the area of ​​the outer surface of pipe 1A that requires scraping, region R between mark 12b and second end 22, which is the end closest to mark 12b. In this case, for example, when scraping region R between mark 12b and second end 22, which is the end closest to mark 12b, an installer may determine whether scraping has been completed successfully by confirming whether mark 12b on pipe 1A has been scraped away and disappeared by the scraping. Note that "successful scraping" may refer to a state in which the surface layer of pipe body 10 has been removed to the depth to be scraped (scraper processing depth) in the area to be scraped by the scraping process.

[0019] In this embodiment, the first mark 11 is printed in the form of dots on the outer surface of the pipe body 10. The shape of the first mark 11 is not limited as long as it allows the installer to confirm the center of gravity. The shape of the first mark 11 may be, for example, a line or a predetermined symbol such as an x. In this embodiment, the first mark 11 is formed by printing a predetermined shape (dot) on the outer surface of the pipe body 10, but the method is not limited to printing and can be appropriately set depending on, for example, the material of the pipe 1. The first mark 11 may be formed, for example, by cutting a groove in the outer surface of the pipe body 10, or by wrapping tape or attaching a sticker to the outer surface of the pipe body 10.

[0020] The pipe 1A shown in Fig. 1 has the same cross-sectional shape and outer diameter along its axial direction. The center of gravity of the pipe 1A shown in Fig. 1 is located at a position that bisects the longitudinal direction of the pipe body 10. Therefore, the first mark 11 on the pipe 1A shown in Fig. 1 is located at a position that bisects the longitudinal direction of the pipe body 10.

[0021] The pipe 1B shown in FIG. 2 is a straight pipe with a single bearing. Therefore, of the two ends (first end 21 and second end 22) of the pipe body 10, one (first end 21) has a different shape from the other (second end 22). Therefore, the center of gravity of the pipe 1 shown in FIG. 2 is shifted toward one of the two ends of the pipe body 10 from the position that divides the pipe body 10 into two equal parts in the longitudinal direction. Specifically, the first end 21 is a socket used for connecting to other components, and therefore has a larger diameter than the straight pipe portion including the second end 22. In the illustrated example, the center of gravity of the pipe 1 is shifted toward the first end 21 of the pipe body 10 from the position that divides the pipe body 10 into two equal parts in the longitudinal direction. Therefore, the first mark 11 of the pipe 1 shown in FIG. 2 is positioned closer to the first end 21 of the pipe body 10 from the position that divides the pipe body 10 into two equal parts in the longitudinal direction.

[0022] As shown in Figure 1, the scale 12a, which is the second mark 12 in this embodiment, is printed in the form of a line on the outer surface of the pipe body 10. The shape of the scale 12a is not limited as long as it allows the installer to check the position in the longitudinal direction of the pipe body 10. The intervals between the scales 12a are not limited, but may be, for example, 5 cm, 10 cm, or 50 cm.

[0023] The mark 12b, which is the second mark 12 in this embodiment, is printed as a symbol (x) on the outer surface of the pipe body 10. The shape of the mark 12b is not limited as long as it is provided so that the installer can confirm the position corresponding to, for example, the insertion amount of the pipe 1A into another member to be connected.

[0024] The shape of the second mark 12 may be, for example, a line, a dot, or a predetermined symbol such as an X. In this embodiment, the second mark 12 is provided by printing a predetermined shape on the outer surface of the pipe body 10, but the method is not limited to printing and can be appropriately set depending on, for example, the material of the pipe 1. The second mark 12 may be provided, for example, by cutting a groove in the outer surface of the pipe body 10, or by wrapping tape or attaching a sticker to the outer surface of the pipe body 10.

[0025] In this embodiment, a band-shaped portion 14 extending in the longitudinal direction of the pipe body 10 is provided on the outer surface of the pipe body 10. The first mark 11 and the second mark 12 in this embodiment are provided in a position overlapping the band-shaped portion 14. The band-shaped portion 14 does not have to be provided on the outer surface of the pipe body 10, and the arrangement of the first mark 11 and the second mark 12 is not limited to being provided in a position overlapping the band-shaped portion 14. Only the second mark 12 may be provided in a position overlapping the band-shaped portion 14, or only the scale 12a of the second mark 12 may be provided in a position overlapping the band-shaped portion 14, and the mark 12b may not be provided in a position overlapping the band-shaped portion 14.

[0026] 1, the band-shaped portion 14 extends longitudinally from the first end 21 to the second end 22 of the pipe body 10. That is, in the illustrated example, the band-shaped portion 14 is also provided in the area of ​​the outer surface of the pipe 1A that requires scraping. In this case, for example, when scraping the area R between the second end 22, which is the end closest to the mark 12b, and the mark 12b, the installer may be able to determine whether the scraping has been completed successfully by checking whether not only the mark 12b of the pipe 1A but also the band-shaped portion 14 has been scraped away and disappeared by the scraping.

[0027] The marks (first mark 11 and second mark 12) in this embodiment are provided on a portion of the circumference of the pipe body 10, but the arrangement of the marks is not limited to the above. The marks may be provided so as to be visible from any position in the circumference of the pipe body 10. The marks may be provided, for example, continuously around the entire circumference of the pipe body 10. The marks may be provided, for example, discontinuously (for example, in a dotted line) around the entire circumference of the pipe body 10.

[0028] The pipe 1A of this embodiment is placed in an underground space through a vertical shaft, for example, as follows. FIG. 3 is a schematic diagram showing the pipe 1 of this embodiment in a lifted state. The pipe 1A of this embodiment has a first mark 11 on the outer surface of the pipe body 10. As shown in FIG. 3, the pipe 1 of this embodiment is connected to a hoisting tool and suspended at a single point. Specifically, a wire 210 is connected to the position of the first mark 11, and the wire 210 is connected to a hook 220 of a crane, thereby achieving single-point suspension. The single-point suspended pipe 1 is suspended within a shaft and placed, for example, in an underground space in which an existing pipe 100 is installed. There are no particular limitations on the method for connecting the wire 210 to the position of the first mark 11.

[0029] FIG. 4 is a schematic diagram showing a state in which the pipe 1A of this embodiment is inserted into an existing pipe 100. The pipe 1A of this embodiment has a scale 12a (second mark 12) on the outer surface of the pipe body 10. As shown in Fig. 4, when the pipe 1 of this embodiment is inserted into the existing pipe 100, the installer can easily check the insertion length of the pipe 1A into the existing pipe 100 by checking the scale 12a on the outer surface of the pipe 1A protruding from the existing pipe 100, for example.

[0030] (First Modification) Next, a first modified example of the pipe 1 of this embodiment will be described. 5 is a schematic diagram showing a state in which a pipe 1C of the first modified example is lifted by two-point lifting. Two-point lifting means that a lifting tool is connected to the pipe 1 at two points and the pipe is lifted. As shown in Figure 5, the pipe 1C of the first modified example has, in addition to a first mark 11 indicating the center of gravity position and a scale 12a (second mark 12), a third mark 13 provided at a position where the wire 210 is connected when hanging at two points. The shape of the third mark 13 and the method of providing it on the outer surface of the tube body 10 may be similar to those of the first mark 11, and therefore detailed description thereof will be omitted. The third mark 13 of the first modified example is provided in a dot-like manner, similar to the first mark 11. However, the shapes of the first mark 11 and the second mark 12 do not have to be the same. For example, the first mark 11 may be provided in a dot-like manner, and the third mark 13 may be provided in a line-like manner. When the third mark 13 is provided in a line-like manner, the length of the line of the third mark 13 may be different from the length of the line indicating the graduations 12a of the second mark 12. For example, the line of the third mark 13 may be longer than the line indicating the graduations 12a of the second mark 12, or may be shorter than the line indicating the graduations 12a of the second mark 12.

[0031] 5, the pipe 1C of the first modified example is suspended at two points with a wire 210 connected to the position of the third mark 13. The two-point suspended pipe 1C is suspended, for example, in a vertical shaft and placed in an underground space where an existing pipe 100 is installed. The method of connecting the wire 210 to the position of the third mark 13 is not limited.

[0032] (Second Modification) Next, a second modified example of the pipe 1 of this embodiment will be described. The pipe body 10 of the pipes 1D and 1E of the second modified example has a displacement suppression part 15 at the center of gravity. When a lifting tool such as a wire 210 is connected to the center of gravity, the displacement suppression part 15 prevents the lifting tool from shifting from the center of gravity. As will be described in detail later, the displacement suppression part 15 provided at the center of gravity may itself be the first mark 11 indicating the center of gravity of the pipes 1D and 1E. Specifically, the displacement suppression part 15 may have the following configuration.

[0033] FIG. 6 shows an example of a pipe 1D according to a second modified example. As shown in Fig. 6, the pipe body 10 of the second modification has an anti-slip portion 16 provided at the center of gravity as the slippage suppression portion 15. The anti-slip portion 16 may be provided, for example, by increasing the surface roughness of a portion of the outer surface of the pipe body 10 that includes the center of gravity, or by wrapping tape with anti-slip properties around the outer surface of the pipe body 10 that includes the center of gravity. Note that the anti-slip portion 16 may be provided continuously around the entire circumferential direction of the pipe body 10 as shown in the figure, but it may also be provided intermittently (e.g., in a dotted line pattern), or may be provided only on a portion of the circumferential direction of the pipe body 10.

[0034] 6, the first mark 11 is provided on the non-slip portion 16, but the configuration is not limited to this. For example, the first mark 11 may not be provided on the non-slip portion 16, and the non-slip portion 16 itself may be the first mark 11 indicating the center of gravity position. The color of the non-slip portion 16 may be different from the color of the area of ​​the outer surface of the pipe body 10 excluding the non-slip portion 16.

[0035] FIG. 7 shows an example of a pipe 1E according to a second modified example. As shown in FIG. 7 , the pipe body 10 of the second modified example has a recess 17 provided at the center of gravity as the displacement suppression portion 15. For example, as shown in FIG. 7 , the recess 17 may be provided by forming two expanded diameter portions whose diameters are larger than the outer diameter of the pipe body 10 at positions axially sandwiching the center of gravity. The expanded diameter portion on the first end 21 side is designated as the first expanded diameter portion 17a, and the expanded diameter portion on the second end 22 side is designated as the second expanded diameter portion 17b. The configuration of the recess 17 is not limited to the example shown in the figure, and may be provided, for example, by forming a reduced diameter portion whose diameter is smaller than the outer diameter of the pipe body 10 in a region including the center of gravity. Note that the recess 17 may be provided continuously around the entire circumferential direction of the pipe body 10 as shown in the figure, or may be provided intermittently (e.g., in a dotted line pattern), or may be provided only in a portion of the circumferential direction of the pipe body 10.

[0036] 7, the first mark 11 is provided in the recess 17, but the configuration is not limited to this. For example, the first mark 11 may not be provided in the recess 17, and the recess 17 itself may be the first mark 11 that indicates the center of gravity position.

[0037] FIG. 8 is a schematic diagram showing a state in which the pipe 1E of the second modified example is lifted and tilted. The pipes 1D and 1E of the second modified example have a displacement suppression portion 15 (recess 17) provided on the outer surface of the pipe body 10 and a first mark 11 provided on the displacement suppression portion 15. As shown in FIG. 8 , the pipe 1E of the second modified example is connected to a hoisting tool and suspended at a single point. Specifically, a wire 210 is connected to the position of the first mark 11, and the wire 210 is connected to a crane hook 220, thereby achieving a single-point suspension. The single-point suspended pipe 1E is suspended within a shaft and placed, for example, in an underground space in which an existing pipe 100 is installed. At this time, as shown in the figure, the pipe 1E may be installed within the shaft while avoiding obstacles such as struts within the shaft by appropriately tilting the pipe 1E around the center of gravity where the wire 210 is connected.

[0038] In the pipe 1E of the second modification, the wire 210 can be connected to the recess 17 located at the center of gravity of the pipe 1E. This prevents the connection position of the wire 210 from shifting from the center of gravity of the pipe 1E, for example, when the pipe 1E is lifted using a single-point lifting method during construction. In particular, even when the pipe 1E is tilted during construction, the connection position of the wire 210 can be prevented from shifting from the center of gravity of the pipe 1E. Specifically, as shown in the figure, when the second end 22 is tilted upward around the center of gravity where the wire 210 is connected, even if a force is applied in a direction that shifts the wire 210 from the center of gravity toward the second end 22, the second enlarged diameter portion 17b prevents the connection position of the wire 210 from shifting from the center of gravity of the pipe 1E.

[0039] Note that the example in Figure 8 shows a case where a recess 17 is provided as the slippage prevention portion 15, but in the case of a pipe 1D where an anti-slip portion 16 is provided as the slippage prevention portion 15, the anti-slip portion 16 can similarly prevent the connection position of the wire 210 from shifting from the center of gravity of the pipe 1D.

[0040] As described above, the pipe 1 of this embodiment is a pipe 1 comprising a pipe body 10 and marks provided on the outer surface of the pipe body 10, and the marks include a first mark 11 provided at the center of gravity of the pipe 1 and at least one second mark 12 provided at a distance from the center of gravity. At the construction site, the pipe 1 may be lifted for construction. In this case, it may be necessary to grasp the position of the center of gravity of the pipe 1 in order to lift the pipe 1. Furthermore, when constructing the pipe 1, it is preferable for the constructor to appropriately check whether the process is being completed normally. With the above-described configuration, the installer can easily grasp the position of the center of gravity of the pipe 1 by checking the first mark 11 provided at the position of the center of gravity of the pipe 1, and can easily lift the pipe 1. Furthermore, the installer can easily check the state of the installation, for example, by checking the insertion depth of the pipe 1 when inserting the pipe 1 into the existing pipe 100, by using at least one second mark 12 provided away from the position of the center of gravity. Therefore, the pipe 1 can be easily lifted and has excellent installation properties.

[0041] Second mark 12 may also be a plurality of graduations 12a provided at equal intervals in the longitudinal direction of tube body 10. With this configuration, the installer can grasp the state of construction by checking the scale 12a, which is the second mark 12. For example, when inserting the pipe 1 into the existing pipe 100 during construction, the installer can easily grasp how far the pipe 1 has been inserted into the existing pipe 100 by checking the scale 12a. This makes it possible to provide a pipe 1 that is easy to lift and has excellent construction properties.

[0042] The second mark 12 may be a mark 12b provided at a position corresponding to the insertion amount of the pipe 1 into another member to be connected. When the pipe 1 is inserted into another member (for example, a joint), if the insertion amount of the pipe 1 into the joint is insufficient, poor installation may occur. With the above configuration, the installer can easily determine whether the pipe 1 is sufficiently inserted into the fitting by checking the mark 12b, which is the second mark 12, on the surface of the pipe body 10. This can prevent, for example, the pipe 1 from being insufficiently inserted into the fitting, thereby preventing installation defects. Furthermore, for example, if the fitting is an electrofusion joint, and the mark 12b of the second mark 12 indicates the scraping position on the pipe 1, the installer can easily determine the area on the pipe 1 that needs to be scraped. At this time, the installer can easily confirm whether the scraping has been completed successfully by checking, for example, whether the mark 12b on the pipe 1 has been scraped off and disappeared by the scraping. This allows the pipe 1 to be easily lifted and has excellent installation properties.

[0043] The center of gravity may be located closer to one of the two ends of the pipe body 10 than the position that divides the pipe body 10 into two equal parts in the longitudinal direction. For example, in a single-end pipe, the center of gravity may be biased toward one of the two ends of the pipe body 10 rather than the position that divides the pipe body 10 into two equal parts (the center) in the longitudinal direction. In this case, it may take more effort for a builder to determine the center of gravity of the pipe 1B, which has a biased center of gravity, at the construction site, compared to the pipe 1A, which has a center of gravity in the center. With the above-described configuration, the first mark 11 is provided in advance at the center of gravity, so that the installer can easily ascertain the center of gravity position even for a pipe 1B whose center of gravity is offset by checking the first mark 11. This makes it possible to provide a pipe 1 that is easy to lift and has excellent workability.

[0044] The pipe body 10 may also have a recess 17 provided at the center of gravity. For example, when installing pipe 1 in a vertical shaft, wire 210 may be connected to the center of gravity of pipe 1, and pipe 1 may be lifted using a single-point lifting technique. Also, at construction sites where a relatively small pipe 1 having an outer diameter of about 20 mm to 200 mm is used, the vertical shaft or underground space may be narrow. In such cases, pipe 1 may be installed in the vertical shaft while avoiding struts and the like in the shaft by appropriately tilting pipe 1 around the center of gravity where wire 210 is connected. With the above configuration, the wire 210 can be connected to the recess 17 located at the center of gravity of the pipe 1E. This makes it possible to prevent the connection position of the wire 210 from shifting from the center of gravity of the pipe 1E, for example, when the pipe 1E is lifted using a single-point lift during construction. In particular, even if the pipe 1E is tilted during construction, it is possible to prevent the connection position of the wire 210 from shifting from the center of gravity of the pipe 1E. This makes it possible to provide a pipe 1E that is easy to lift and has excellent workability.

[0045] The pipe body 10 may also have an anti-slip portion 16 provided at the center of gravity. With this configuration, the wire 210 can be connected to the anti-slip portion 16 located at the center of gravity of the pipe 1D. This makes it possible to prevent the connection position of the wire 210 from shifting from the center of gravity of the pipe 1D, for example, when the pipe 1D is lifted using a single-point lift during construction. In particular, even if the pipe 1D is tilted during construction, it is possible to prevent the connection position of the wire 210 from shifting from the center of gravity of the pipe 1D. This makes it possible to provide a pipe 1D that is easy to lift and has excellent workability.

[0046] Furthermore, at least one of the first mark 11 and the second mark 12 may be provided over the entire circumference of the tube main body 10 in the circumferential direction. With this configuration, the marks provided around the entire circumferential direction of the pipe body 10 can be seen at any position around the pipe 1. Therefore, even if the pipe 1 is installed in a predetermined position and visual inspection of a portion of the circumferential direction of the pipe 1 becomes difficult, the marks can be identified by checking the marks at a visible circumferential position. This makes it possible to provide a pipe 1 that is easy to lift and has excellent workability.

[0047] The above describes one embodiment of the present disclosure with reference to the drawings, but the specific configuration is not limited to this embodiment, and includes changes, combinations, deletions, etc. of the configuration within the scope that does not deviate from the gist of the present disclosure.

[0048] For example, as in the first modified example, a displacement suppression portion 15 as shown in the second modified example may be provided at a position overlapping with the third mark 13 provided at the position where the wire 210 is connected during two-point suspension. For example, the band-shaped portion 14 may be configured with printing indicating the type of pipe, etc. [Explanation of symbols]

[0049] 1, 1A, 1B, 1C, 1D, 1E Pipes 10 Tube body 11 First Mark 12 Second Mark 12a Scale 12b Landmark 13 Third Mark 14 Belt 15 Misalignment prevention section 16 Anti-slip part 17 Recess 17a 1st enlarged diameter section 17b Second enlarged diameter section 21 First end 22 Second end 100 Existing pipes 200 Hanging Device 210 Wire 220 Hook R area

Claims

1. A tube body; a mark provided on the outer surface of the pipe body; A pipe comprising: The marks include a first mark provided at a center of gravity of the pipe, and at least one second mark provided at a distance from the center of gravity. pipe.

2. The second mark is a plurality of scales provided at equal intervals in the longitudinal direction of the tube body. The pipe of claim 1.

3. The second mark is a mark provided at a position corresponding to the insertion amount of the pipe into another member to be connected. The pipe of claim 1.

4. The center of gravity is biased toward one of the two ends of the pipe body relative to a position that divides the pipe body into two equal parts in the longitudinal direction. The pipe of claim 1.

5. The pipe body has a recess provided at the center of gravity. The pipe of claim 1.

6. The pipe body has an anti-slip portion provided at the center of gravity. The pipe of claim 1.

7. At least one of the first mark and the second mark is provided over the entire circumferential circumference of the pipe body. A pipe according to any one of claims 1 to 6.

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