JP2004108498A - Tubular body insertion carriage - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a tubular body insertion carriage capable of being mounted on tubular bodies of various outer diameters to be used, and securing sufficient electric insulation. <P>SOLUTION: This tubular body insertion carriage 10 is composed of an upper band 30 composed of a pipe spacer made out of a resin and covering an upper outer periphery of the tubular body 12, and a lower band 40 comprising a roller supporting part 42 covering and supporting a lower outer periphery of the tubular body 12 and rotatably supporting a plurality of axially running rollers 21, 22. The bands are respectively made out of a flexible resin material, provided with flange parts for connection 33, 34, 43 on their circumferential end parts, the sum of inner peripheral lengths of each band is shorter than an outer peripheral length of the tubular body, and the tubular body is fastened and fixed by using the lower band having the peripheral length same as the tubular bodies of various outer diameters and the upper band selected from commercially available standard products of resin pipe spacers. Further a resin reinforcement plate 50 for inhibiting the flexure of the roller supporting part is mounted along the roller supporting part. <P>COPYRIGHT: (C)2004,JPO

Description

【００５６】
【発明の効果】
請求項１に記載の管体挿入台車によれば、呼び径で例えば４００Ａ、５００Ａ、６００Ａというように異なる外径の管体に下部バンドを共通して使用でき、さらに、市販の樹脂製パイプスペーサーの規格品から選択される上部バンドを用いているので、コスト的に優れ、さらに、十分な電気絶縁性を確保でき、しかも、樹脂製補強板によりローラ支持部の撓みを抑えているので、ローラの円滑な回転を維持して管体の挿入作業を円滑に行うことが可能となる。
【００５７】
請求項２に記載の発明によれば、市販の樹脂製パイプスペーサーの規格品から選択した複数のセグメントを組み合わせて上部バンドとしたので、対象となる管体の外径に合致した上部バンドを簡単かつ安価に得ることができる。
【００５８】
請求項３に記載の発明によれば、ローリング防止台車として使用することが可能となる。
【００５９】
請求項４に記載の発明によれば、電気絶縁性をより一層確保して、管体における電食の発生を防止することができる。
【図面の簡単な説明】
【図１】本発明の実施形態に係る管体挿入台車が取り付けられた管体を鞘管内に挿入配管している状態を挿入方向に沿う後方側（発進坑側）から見た正面図である。
【図２】管体に取り付けられた管体挿入台車の側面図である。
【図３】管体の挿入方向に対して管体挿入台車のローラの回転方向が傾いている状態を示す図１の矢印３に沿う矢視図である。
【図４】管体挿入台車の上部バンドおよび下部バンドを組み付ける前の状態を示す正面図である。
【図５】図５（Ａ）は、下部バンドを示す図１の矢印５に沿う矢視図、図５（Ｂ）は、下部バンドのローラ支持部に沿わせて配置される樹脂製補強板を示す図である。
【図６】図６（Ａ）（Ｂ）（Ｃ）は、それぞれ、呼び径４００Ａ、５００Ａ、６００Ａの管体に装着固定される管体挿入台車を示す図である。
【符号の説明】
１０…管体挿入台車
１１…鞘管
１２…管体
２１、２２…ローラ
３０…上部バンド
３１…セグメント
３３、３４…上下のフランジ部（接続用のフランジ部）
４０…下部バンド
４１…フレーム部
４２…ローラ支持部
４３…接続用のフランジ部
４５ａ、４５ｂ…支持リブ
５０…樹脂製補強板
４８０、６４０…市販の樹脂製パイプスペーサーの規格品のセグメント
ＣＬ１、ＣＬ２…クリアランス[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to an improvement in a tube insertion cart that is used by being attached to a tube when inserting and piping the tube into a sheath tube previously laid.
[0002]
[Prior art]
When installing pipes such as gas conduits underground across rivers, roads, railways, etc., to protect the pipes from uneven settlement due to fluctuations in earth pressure, etc. A double-structured pipe that passes through a pipe is adopted. It should be noted that the sheath pipe includes an aging existing pipe in the existing pipe renewal method or the pipe-in-pipe method.
[0003]
As a method of inserting and piping a pipe into a sheath pipe laid in advance, if the insertion pipe distance is short, a plastic pipe spacer (for example, “Piping Smoother” manufactured by Nishiyama Co., Ltd.) is placed around the outer circumference of the pipe. It can be installed and inserted, but if the insertion distance is long, the frictional resistance will increase.Therefore, the pipe insertion work while attaching the pipe insertion cart equipped with rollers to the pipe to prevent damage to the anticorrosive coating layer of the pipe, There is known a technique for facilitating the operation.
[0004]
As a conventional tube insertion cart, a lower ring attachment (a lower band) having a pair of rollers for traveling in the axial direction and an upper ring attachment (an upper band) are provided at appropriate intervals of a tube inserted into the sheath tube. 2. Description of the Related Art There is known a bogie that is fastened and fixed using (for example, see Patent Document 1). In this carriage, the rollers are provided so as to be inclined outward with respect to the insertion direction, so that the tube body does not rotate when moving and does not fall or roll.
[0005]
Although the material of the upper and lower ring attachments of the truck disclosed in Patent Document 1 is not particularly specified, a steel band is usually used, and a rubber plate is interposed between the steel band and the tube. The coating on the body is not damaged. In the above-mentioned bogie, dedicated upper / lower ring attachments are manufactured and used for each size of the pipe to be used (for example, 400 A, 500 A, and 600 A in nominal diameter).
[0006]
Further, as another conventional tube insertion cart, there is also known a cart in which a plurality of divided resin bands, each having no flexibility, which are not flexible, are fastened to the outer periphery of the tube body. In this bogie, since a band made of a hard resin having no flexibility is hard, a dedicated split band is manufactured and used for each size of a tube to be used.
[0007]
[Patent Document 1]
JP 2001-21063 A
[0008]
[Problems to be solved by the invention]
However, if exclusive upper / lower ring attachments are manufactured for each size of the pipe to be used as in the former truck, an increase in manufacturing cost cannot be avoided. Further, in the case of a steel band, the same shaped product cannot be mass-produced as in the case of resin injection molding, and from this point, an increase in manufacturing cost is inevitable.
[0009]
Even in the latter case, if dedicated split bands are manufactured for each size of the pipe to be used, it is necessary to manufacture various types of resin molding dies, so that an increase in manufacturing cost is inevitable.
[0010]
By the way, when inserting a pipe into the sheath pipe and burying it without removing it, and injecting grout material such as earth and sand or foam mortar around it, cut off the inflow of stray current and the cathodic protection current flowing to the flow pipe body Therefore, it is necessary to ensure an insulation state.
[0011]
In the former bogie, electrical insulation is ensured to some extent by interposing a rubber plate between the steel band and the tube, but it cannot be said to be sufficient.
[0012]
For this reason, for example, there is a demand for a tube insertion cart excellent in versatility that can be used by being attached to tubes having different outer diameters such as 400 A, 500 A, and 600 A in nominal diameter, and further ensuring sufficient electrical insulation. ing.
[0013]
The present invention has been made in order to satisfy such a demand, and its purpose is to attach and use a pipe having a different outer diameter such as 400 A, 500 A, or 600 A in nominal diameter. Another object of the present invention is to provide a tube insertion cart capable of securing sufficient electric insulation.
[0014]
[Means for Solving the Problems]
The object of the present invention is achieved by the following means.
[0015]
(1) When inserting a pipe into a sheath pipe laid in advance, in a pipe insertion cart used by attaching to the pipe,
The bogie includes an upper band formed of a resin pipe spacer that covers an upper outer periphery of the tubular body, and a roller support that covers and supports a lower outer periphery of the tubular body and rotatably supports a plurality of axial traveling rollers. And a lower band comprising a part,
Each of the bands is formed of a flexible resin material, and is provided with a connecting flange at a circumferential end thereof, and the sum of the inner circumferential lengths of the respective bands is equal to the outer circumferential length of the tubular body. Shorter,
Using a lower band having the same circumference for tubes having different outer diameters and an upper band selected from standard products of commercially available resin pipe spacers, tightening and fixing the tube,
Further, a tube insertion cart is characterized in that a resin reinforcing plate for suppressing the deflection of the roller support is arranged along the roller support.
[0016]
(2) The tube insertion cart according to (1), wherein a plurality of segments selected from standard products of commercially available resin pipe spacers are combined as the upper band.
[0017]
(3) The two roller supporting portions provided on the lower band are integrally formed with the lower band by inclining the roller rotation surface outward with respect to the insertion direction of the tube, thereby forming a rolling prevention cart. The tube insertion cart according to the above (1) or (2), characterized in that:
[0018]
(4) The tube insertion cart according to any one of (1) to (3), wherein the roller is formed of a resin material having electrical insulation.
[0019]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
[0020]
FIG. 1 shows a state in which a pipe 12 to which a pipe insertion carriage 10 according to an embodiment of the present invention is attached and inserted into a sheath pipe 11 is viewed from the rear side (starting pit side) along the insertion direction. FIG. 2 is a front view, FIG. 2 is a side view of the tube insertion cart 10 attached to the tube 12, and FIG. 3 is a diagram illustrating the rotation direction of the rollers 21 and 22 of the tube insertion cart 10 with respect to the insertion direction of the tube 12. FIG. 4 is a front view showing a state before the upper band 30 and the lower band 40 of the tube insertion cart 10 are assembled, and FIG. FIG. 5B is a view showing the lower band 40, taken along an arrow 5 in FIG. 1, and FIG. 5B is a view showing a resin reinforcing plate 50 arranged along the roller supporting portion 42 of the lower band 40.
[0021]
As shown in FIGS. 1 and 2, when inserting a pipe 12 such as a gas pipe into a sheath pipe 11 laid in advance, a pipe insertion carriage 10 is provided in a longitudinal direction of the outer circumference of the pipe 12. Used at appropriate intervals.
[0022]
The tube insertion cart 10 can be roughly described as an upper band 30 made of a resin pipe spacer that covers an upper outer periphery of the tube 12, supports the lower periphery of the tube 12 so as to be supported, and has a plurality of axial traveling members. And a lower band 40 having a roller supporting portion 42 that rotatably supports the rollers 21 and 22. Each of the bands 30 and 40 is formed of a flexible resin material, has flange portions 33, 34 and 43 for connection at circumferential ends, and has an inner peripheral length of each of the bands 30 and 40. Is smaller than the outer peripheral length of the pipe body 12, and the lower band 40 having the same circumferential length for the pipe bodies having different outer diameters, and the upper band 30 selected from standard products of commercially available resin pipe spacers. The pipe 12 is fastened and fixed. Further, a resin reinforcing plate 50 for suppressing the bending of the roller supporting portion 42 is arranged along the roller supporting portion 42. The details will be described below.
[0023]
In the present specification, the level of “different outer diameter” is not intended to mean an outer diameter difference of about several millimeters, and for example, an outer diameter difference between pipes such as 400 A, 500 A, and 600 A in nominal diameter. It is intended.
[0024]
First, as shown in FIG. 1, the rollers 21 and 22 are arranged as a pair of two wheels at left and right symmetric positions diagonally below the outer periphery of the tube 12. A pair of rollers 21 and 22 are provided such that a line extending in the radial direction from the center of the sheath tube 11 and a roller rotation axis are substantially perpendicular to each other when viewed in a section perpendicular to the axis of the sheath tube 11 and the tube body 12. I have. With this configuration, the rollers 21 and 22 are in contact with the inner peripheral surface of the sheath tube 11 so as to be substantially perpendicular thereto, so that smooth running is ensured.
[0025]
Referring to FIG. 3, the insertion direction of tube 12 or the traveling direction of rollers 21 and 22 is indicated by arrow S. Each of the rollers 21 and 22 is attached such that its rotation surface is inclined outward with respect to the insertion direction S. The opening angle θ from the insertion direction S is about 1 to 5 degrees. In the present embodiment, the opening angle θ is set to 4 degrees. Reference numeral 49 in FIG. 3 indicates an arrow protruding from the lower band 40 or an arrow sticker attached to the lower band 40 in order to confirm the traveling direction of the lower band 40.
[0026]
By inclining each of the rollers 21 and 22 outward with respect to the insertion direction S, the tube 12 can be inserted into the sheath tube 11 while the rotation of the tube 12 is suppressed. For example, when the pipe body 12 rotates clockwise from the state shown in FIG. 1, the load applied to the roller 21 on the right side in the figure becomes larger than the load applied to the roller 22 on the left side in the figure. Since the balance between the rotational force of the roller 21 and the rotational force of the roller 22 is lost, the tube 12 tends to rotate in the rotational direction of the roller 21 having the larger load. In this example, the tube 12 rotates counterclockwise. As a result, the rotated tube 12 returns to the position shown in FIG. 1 where the rotational forces of the rollers 21 and 22 are balanced. As described above, when the tube 12 rotates in any direction while the tube 12 is inserted into the sheath tube 11 and the positions of the rollers 21 and 22 deviate from the normal positions shown in FIG. , A rotational force is generated which attempts to return the rollers 21 and 22 to the positional deviation. Thus, the tube 12 can be inserted without substantially rotating the tube 12.
[0027]
The upper band 30 is formed of a resin-made pipe spacer that covers the upper outer periphery of the tube 12. Generally, a resin-made pipe spacer is mounted on the outer periphery of a tubular body, and is widely used when inserting and piping the tubular body while sliding on the inner circumferential surface of the sheath tube. The pipe spacer is commercially available, for example, from Nishiyama Corporation under the name "Piping Smoother". Commercially available resin pipe spacers include a plurality of types of standard products having different circumferential lengths.
[0028]
Referring to FIG. 1, as an upper band 30 in the embodiment, a plurality (two in the illustrated example) of the same shape segments 31, 31 selected from standard products of commercially available resin pipe spacers are combined. The segment 31 is provided at a frame portion 32 covering the outer periphery of the tube body 12, an upper flange portion 33 for connection provided at an upper end in the circumferential direction of the frame portion 32, and at a lower end of the frame portion 32 in the circumferential direction diagram. And a runner 35 protruding radially outward from the outer periphery of the frame portion 32. The frame portion 32, the upper flange portion 33, the lower flange portion 34, and the runner 35 are integrally formed from a resin material by injection molding or the like. The upper flange portion 33 is formed with a plurality of through holes (three in the illustrated example) through which the bolts 36 are inserted. The upper band 30 is formed by connecting the upper flange portions 33 via the bolts 36. In the lower flange portion 34, through holes (two in the illustrated example) through which bolts 44 for connecting to the lower band 40 are inserted are formed.
[0029]
The lower band 40 includes a roller supporting portion 42 that covers and supports a lower outer periphery of the tubular body 12 and rotatably supports a plurality of rollers 21 and 22 for traveling in the axial direction. A flange portion 43 for connection is provided at each of both ends in the circumferential direction of the frame portion 41 covering the outer periphery of the tube body 12. The frame portion 41, the flange portion 43, and the roller support portion 42 are integrally formed from a resin material by injection molding or the like. The frame 41 of the lower band 40 is connected to the circumferential end of the upper band 30 by connecting the flange 43 and the lower flange 34 via bolts 44.
[0030]
The lower band 40 has the same circumferential length for pipes having different outer diameters, while the upper band 30 is selected from standard products of commercially available resin pipe spacers. The pipe 12 is fastened and fixed.
[0031]
As described above, the upper band 30 uses a combination of a plurality of segments 31 selected from commercially available standard products, but when selecting the segment 31, the sum of the inner peripheral lengths of the respective bands 30, 40 is determined. It is designed to be close to the outer peripheral length of the tube 12 and shorter. Due to this circumferential length difference, a clearance CL1 is generated between the upper band 30 and the lower band 40, a clearance CL2 is generated between the upper flange portions 33 of the segments 31, and the upper band 30 and the lower band 40 are fastened to the tube 12. It can be fixed.
[0032]
In the illustrated example, the upper band 30 and the lower band 40 are connected to each other by bolts 36 and 44 via a rubber plate 60 that protects the anticorrosion coating applied to the outer periphery of the tube 12 and are tightened. It is attached to the outer periphery of the body 12. When the rubber plate 60 is covered in this manner, the outer peripheral length of the tubular body 12 is the outer peripheral length of the outer diameter dimension in consideration of the thickness of the interposed rubber plate 60.
[0033]
In addition, the circumferential length of the lower outer periphery of the tube body 12 to be covered by the lower band 40 is not particularly limited, and can be appropriately selected. FIG. 1 shows a state in which the lower band 40 is attached to the tube 12 having a nominal diameter of 400 A. In this case, the circumference of the lower band 40 is in a range of about 95 degrees with respect to the center of the tube 12. Is set to a length that covers the outer periphery of the lower part of the tube 12. When the same lower band 40 is attached to a tube having a nominal diameter of 300A, the lower periphery of the tube is covered in a range of about 120 degrees. Will cover the lower periphery.
[0034]
The roller support portion 42 has a pair of support ribs 45a and 45b protruding outward from the outer periphery of the frame portion 41. The pair of support ribs 45a and 45b are provided at a predetermined interval. The rollers 21 and 22 are rotatably supported by the support ribs 45a and 45b via a roller shaft 46 provided through the support ribs 45a and 45b. The roller shaft 46 includes a bolt 46a and a nut 46b, and the return rotation of the nut 46b is prevented by the split pin 46c.
[0035]
As shown in FIG. 3, the pair of support ribs 45 a and 45 b are provided to be inclined outward with respect to the insertion direction S of the tube 12, and determine the opening angle θ of the rollers 21 and 22. The support rib 45b is connected to the frame 41 via two reinforcing ribs 47b extending in the circumferential direction. Further, as shown in FIG. 5A, the support rib 45a is connected to the frame 41 and the flange 43 via three reinforcing ribs 47a extending in the circumferential direction. A seal 48 indicating the rear surface of the lower band 40 is attached to the rear surface of the reinforcing rib 47b (see FIGS. 1 and 4). It is preferable that the seal 48 be colored red or the like in order to draw the operator's attention. By visually checking the seal 48 from the rear side, the operator can easily confirm that the front and rear of the lower band 40 are correctly attached along the insertion direction.
[0036]
As shown in FIGS. 5A and 5B, the resin reinforcing plate 50 is arranged along the roller supporting portion 42 in order to suppress the bending of the roller supporting portion 42. The resin reinforcing plate 50 has a hole 51 through which the roller shaft 46 is inserted, and a concave portion 52 which is inserted into the central reinforcing rib 47a. The resin reinforcing plate 50 is sandwiched between the bolt 46a of the roller shaft 46 and the support rib 45a. A load is applied to the rollers 21 and 22 in a direction in which the rollers 21 and 22 tend to spread outward in the circumferential direction of the lower band 40. For this reason, the resin reinforcing plate 50 may be disposed along at least the support rib 45a located on the outer side in the circumferential direction of the lower band 40 among the pair of support ribs 45a and 45b.
[0037]
The upper band 30 composed of the lower band 40 and the pipe spacer is formed of a flexible resin material, and the resin reinforcing plate 50 is formed of a resin material having a strength for suppressing the bending of the roller support portion 42. As shown in FIG. 4, each segment 31 constituting the upper band 30 can be bent or deformed in a direction indicated by an arrow A, and the lower band 40 can be bent or deformed in a direction indicated by an arrow B. . When the upper band 30 and the lower band 40 bend or deform, the radius of curvature of each of the frame portions 32 and 41 changes. Also, when the bolts 36 and 44 are fastened, the circumferential clearance CL2 between the upper flange portions 33 and the circumferential clearance CL1 between the lower flange portion 34 and the flange portion 43 are adjusted. The radius of curvature of each of the frame portions 32 and 41 changes. Therefore, the upper band 30 and the lower band 40 are provided with different outer diameters within a range where the upper band 30 and the lower band 40 can be bent and a range where the circumferential clearances CL1 and CL2 can be adjusted. It becomes possible to attach to.
[0038]
Although the roller supporting portion 42 of the lower band 40 has flexibility, in the present embodiment, the resin supporting plate 50 is arranged along the roller supporting portion 42 to suppress the bending of the roller supporting portion 42. For this reason, even if a load is applied to the roller support portion 42, it is possible to prevent the roller support portion 42 from falling down and the hole through which the roller shaft 46 is inserted from being deformed. Thereby, the smooth rotation of the rollers 21 and 22 can be maintained, and the insertion operation of the tube 12 can be performed smoothly.
[0039]
In this specification, the term “resin material having flexibility” can be selected within a range that can achieve the purpose of attaching and sharing the upper band 30 and the lower band 40 to the pipes 12 having different outer diameters. Resin material. The “resin material having flexibility” needs to have a bending strength and a bending elastic modulus that do not break even when bent or deformed in order to be attached to and commonly used for pipes 12 having different outer diameters. In addition, the term “resin material having strength to suppress the bending of the roller supporting portion 42” is used in relation to the selected “resin material having flexibility” to suppress the bending of the roller supporting portion 42 to the rollers 21, 22. Is a resin material that can be selected within a range that can achieve the purpose of maintaining smooth rotation of the resin material. Specifically, the upper band 30 and the lower band 40 are manufactured by injection molding using a flexible thermoplastic resin such as polypropylene (PP). The resin reinforcing plate 50 is preferably made of a resin having a high compressive strength, for example, a resin having a compressive strength of 130 MPa or more. Specifically, the resin reinforcing plate 50 is made of fiber reinforced plastic (FRP), glass fiber reinforced polyethylene terephthalate (GF-PET), polybutylene terephthalate (PBT), or the like having a compressive strength of 130 MPa or more. .
[0040]
Since the upper band 30 and the lower band 40 are formed of a resin material, the rollers 21 and 22 can be formed of a non-insulating material (for example, metal). In order to ensure reliable insulation, each of the rollers 21 and 22 is preferably formed of an electrically insulating resin material, for example, MC nylon.
[0041]
According to the present embodiment configured as described above, one type of lower band 40 to which the rollers 21 and 22 are attached can be used by attaching to the tubes 12 having different outer diameters. There is no need to manufacture a dedicated lower band 40 for each diameter. In other words, it is possible to reduce the types of the lower band 40 to be prepared in advance. Therefore, for example, the number of injection molding dies for manufacturing the lower band 40 can be reduced, and an increase in the manufacturing cost of the lower band 40 can be suppressed through reduction of the mold cost. Further, since the upper band 30 is selected from standard products of commercially available resin pipe spacers, general-purpose products can be used, which is advantageous in cost. Therefore, the tube insertion cart 10 of the present embodiment is versatile in that it can be used by being attached to tubes 12 having different outer diameters, and is excellent in cost.
[0042]
Further, since the upper band 30 is composed of a plurality of segments 31 and 31 selected from standard products of commercially available resin pipe spacers, the upper band 30 that matches the outer diameter of the target pipe 12 can be easily and inexpensively formed. Obtainable.
[0043]
Further, the two roller support portions 42 provided on the lower band 40 are integrally formed with the lower band 40 by inclining the roller rotation surface outward with respect to the insertion direction of the tube 12, thereby forming a rolling prevention cart. , The production accuracy such as the opening angle θ of the rollers 21 and 22 can be ensured.
[0044]
Further, since each of the rollers 21 and 22 is formed of an electrically insulating resin material, even if a stray current passes through the sheath tube 11, the occurrence of electrolytic corrosion (electrochemical corrosion) in the tube 12 is further prevented. be able to.
[0045]
Since the tube insertion cart 10 is made of a resin material except for the bolts 36 and 44 and the roller shaft 46 for fastening, the weight can be reduced, the handling is easy, and the workability at the time of attachment is improved.
[0046]
In addition, although the case where the upper band 30 is configured from the segments 31 having the same shape is illustrated, the present invention is not limited to this case, and the plurality of segments may have an asymmetric shape.
[0047]
Further, the bolts 36, 44 for fastening the bands 30, 40, the roller shaft 46, and the like may be resin products. In the case of such a configuration, generation of electrolytic corrosion can be further prevented.
[0048]
【Example】
A description will be given of an embodiment of a tube insertion cart that is mounted and fixed on tubes having different outer diameters of 400 A, 500 A, and 600 A inserted and piped into a sheath tube.
[0049]
FIGS. 6A, 6B, and 6C are diagrams showing tube insertion carts mounted and fixed to tubes 400, 500, and 600 having nominal diameters of 400A, 500A, and 600A, respectively.
[0050]
The lower band 40 made of polypropylene integrally formed with the roller support portion 42 is used in common for the three types of different tubes 400, 500, and 600.
[0051]
The upper band used was a combination of a plurality of segments 480 and 640 made of polypropylene selected from commercially available standard products. When selecting the segments 480 and 640, the sum of the circumference of the lower band 40 and the circumference of each of the upper bands is equal to the outer circumference of the pipes 400, 500 and 600. (Including the outer peripheral length) and shorter. Due to the difference in circumference, a clearance is generated between the upper band and the lower band 40 and between the joining ends of the segments 480 and 640, so that the upper band and the lower band 40 can be tightened and fixed to the pipes 400, 500 and 600. Become.
[0052]
Table 1 shows a combination example of the specifically set lower band 40 and upper band segments 480 and 640.
[0053]
The lower band 40 having the same circumferential length of 355 mm was used in common for the pipes having the nominal diameters of 400A, 500A, and 600A. For the upper band, the most suitable combination was selected from standardized segment products marketed under the name "Piping Smoother" by Nishiyama Corporation. That is, two segments 480 of type LS-480 were used in 400A, and two segments 640 of type LS-640 were used in 500A. In the case of 600A, a combination of one segment 640 of type LS-640 and two segments 480 of type LS-480 was used.
[0054]
By the selection of these segments 480 and 640, the sum 周 of the circumferences of the lower band 40 and the upper band becomes shorter by 30 to 24 mm than the outer circumference D of each pipe including the thickness of the rubber plate, and an appropriate interference ΔL is obtained. Was.
[0055]
[Table 1]

[0056]
【The invention's effect】
According to the tube insertion cart according to claim 1, the lower band can be commonly used for tubes having different outer diameters such as 400A, 500A, and 600A in nominal diameter, and further, a commercially available resin pipe spacer. Because the upper band selected from the standard products is used, it is excellent in cost, can secure sufficient electrical insulation, and suppresses the deflection of the roller support part by the resin reinforcing plate. It is possible to smoothly insert the tube while maintaining the smooth rotation of the tube.
[0057]
According to the second aspect of the present invention, since the upper band is formed by combining a plurality of segments selected from the standard products of the commercially available resin pipe spacer, the upper band matching the outer diameter of the target pipe can be easily formed. And it can be obtained at low cost.
[0058]
According to the third aspect of the present invention, it is possible to use the anti-rolling cart.
[0059]
According to the fourth aspect of the present invention, it is possible to further ensure electrical insulation and prevent occurrence of electrolytic corrosion in the tubular body.
[Brief description of the drawings]
FIG. 1 is a front view of a state in which a pipe to which a pipe insertion carriage according to an embodiment of the present invention is attached is inserted and piped into a sheath pipe as viewed from a rear side (starting pit side) along an insertion direction. .
FIG. 2 is a side view of a tube insertion cart attached to the tube.
FIG. 3 is a view along arrow 3 in FIG. 1 showing a state in which the rotation direction of the rollers of the tube insertion cart is inclined with respect to the direction of insertion of the tube.
FIG. 4 is a front view showing a state before assembling an upper band and a lower band of the tube insertion cart.
5 (A) is a view of the lower band taken along arrow 5 in FIG. 1, and FIG. 5 (B) is a resin reinforcing plate disposed along the roller support of the lower band. FIG.
6 (A), 6 (B), and 6 (C) are views showing tube insertion carts mounted and fixed on tubes having nominal diameters of 400A, 500A, and 600A, respectively.
[Explanation of symbols]
10 ... Tube insertion cart
11 ... sheath tube
12 ... Tube
21, 22 ... roller
30 ... Upper band
31 ... Segment
33, 34: Upper and lower flange parts (flange parts for connection)
40 ... lower band
41 ... frame part
42 ... Roller support
43 ... Flange for connection
45a, 45b ... support ribs
50 ... Reinforcement plate made of resin
480, 640: Standard segment of commercially available resin pipe spacer
CL1, CL2 ... clearance

Claims (4)

When inserting and piping a pipe (12) into a sheath pipe (11) laid in advance, a pipe insertion cart used by being attached to the pipe (12),
The bogie includes an upper band (30) made of a resin pipe spacer that covers an upper outer periphery of the tubular body (12), and supports and supports a plurality of axial traveling bodies while covering a lower outer periphery of the tubular body (12). A lower band (40) having a roller supporting portion (42) for rotatably supporting the rollers (21, 22),
Each of the bands (30, 40) is formed of a flexible resin material, is provided with a connection flange portion (33, 34, 43) at a circumferential end, and is provided with the respective bands (30, 40). The sum of the inner peripheral lengths of the pipes (30, 40) is shorter than the outer peripheral length of the tubular body (12),
Using the lower band (40) having the same circumference for tubes having different outer diameters and the upper band (30) selected from standard products of commercially available resin pipe spacers, the tube (12) is used. Tighten and fix
Furthermore, a tube insertion cart characterized in that a resin reinforcing plate (50) for suppressing the bending of the roller support portion (42) is arranged along the roller support portion (42). The tube insertion cart according to claim 1, wherein a plurality of segments selected from standard products of commercially available resin pipe spacers are combined as the upper band (30). The two roller support portions (42) provided on the lower band (40) are integrated with the lower band (40) by tilting the roller rotation surface outward with respect to the insertion direction of the tube (12). The tube insertion cart according to claim 1 or 2, wherein the cart is formed as a rolling prevention cart. The tube insertion cart according to any one of claims 1 to 3, wherein the rollers (21, 22) are formed of an electrically insulating resin material.

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