JP2934099B2 - Bundled cable ties for conduits and method of tying them - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of binding a corrugated pipe for a conduit and a plurality of corrugated pipes for a conduit, and more particularly to a method for binding a corrugated pipe for a conduit while maintaining the flexibility of the corrugated pipe for a conduit. The present invention relates to a plurality of corrugated tube bundles for electric conduits, which are bundled so as not to be loosened, and a method for bundling them.

[0002]

2. Description of the Related Art A corrugated pipe for a conduit (hereinafter sometimes simply referred to as a corrugated pipe for the sake of simplicity) has a corrugated structure made of a polyolefin resin, for example, a hard polyethylene resin, such as an arc-shaped or spiral shape. A pipe having high flat compressive strength, moderate flexibility, and excellent workability due to its corrugated structure. Utilizing its properties, a protective tube for electric wires and cables buried underground That is, it refers to a corrugated tube used as a conduit tube.

In order to lay a corrugated pipe for a conduit, first, a groove for laying is dug, and a corrugated pipe is laid in a predetermined arrangement at the bottom of the groove. In order to keep the corrugated pipes from moving when the cable passes through the corrugated pipes, the corrugated pipes are bound or fixed with a fixing plate, and then the grooves are backfilled. In general, when burying electric wires and cables in the ground, the embedding route is limited, so that it is common to embed many wires and cables in the same route. Therefore, a large number of corrugated pipes are arranged in parallel in one stage, or, if one stage is insufficient, are further laid in a plurality of stages. For convenience of storage or transportation, a conventional method of bundling corrugated pipes is a so-called bale stacking method, for example, in which a corrugated pipe is metallized in a schematic sectional form as shown in FIG. Bound with plastic or plastic bands. In addition, a bundle of corrugated pipes for a conduit bundled by such a method is also available on the market.

[0004]

However, this conventional method of binding corrugated pipes has a structure in which corrugated pipes are arranged in multiple stages and bound, except when two corrugated pipes are bound. The bundle of corrugated tubes tied in this manner was inflexible and therefore very difficult to wind on a drum, making it extremely inconvenient to store or transport. Moreover, in the conventional bundling method, the band cannot be used to bind the corrugated pipe, or the bundling cannot be performed due to the use of a flat tape-shaped metal or plastic band and the corrugated shape outside the corrugated pipe. The corrugated pipes slipped with each other, thereby loosening the binding, and it was not possible to bind long corrugated pipes.

Further, in the conventional bundling method, in addition to the lack of flexibility of the corrugated pipe bundle, the corrugated pipes are arranged in a bale-stacking manner and bound, so that the corrugated pipe bundle is kept as it is. Instead of laying in a laying groove, the tied corrugated pipe was once disassembled into individual corrugated pipes, and then the corrugated pipe was laid. In this case, there is a problem that the work of disassembling the bundle of corrugated pipes, bundling and fixing the newly laid corrugated pipes again requires human labor, and the time required for laying for the work is long. . In view of the above problems, an object of the present invention is not to use a multi-stage bale stacking method as in the conventional bundling method, but to impair the original flexibility in a state of being arranged adjacent to each other and in one parallel stage. It is an object of the present invention to provide an elongate corrugated tube tied and a method of tying a long corrugated tube in such a manner that it is bound so as not to be loosened.

[0006]

SUMMARY OF THE INVENTION The inventor of the present invention has repeatedly conducted experiments using actual corrugated conduits for electric conduits as experimental samples, and has found that a bundle of corrugated conduits for conduits which does not slack while maintaining flexibility and the same. After studying the binding method, the present invention was invented. In order to achieve the above object, the bundled product for corrugated pipes of the invention according to claim 1 of the present invention includes a plurality of corrugated pipes for conduits mainly formed of a material made of a polyolefin resin,
Arranged in parallel adjacent to each other, from 30 · P to 90 · P
(Where P is the pitch length of the corrugated tube for corrugated conduits) and has a width W defined by the following equation (1) for each interval of L length selected from the range: Heat-shrinkable plastic endless belt W = (1/60) · L + S (1) (where S is (1 + ／) · P to (4 + ／) ·)
Any value in the range of P. ) Is characterized by being bound in parallel.

According to a second aspect of the present invention, there is provided a method of bundling a plurality of corrugated conduits for a conduit, the plurality of corrugated conduits for a conduit mainly formed of a material made of a polyolefin resin are arranged adjacent to each other. From 30 · P to 90 · P (where P is the corrugated pitch length of the corrugated conduit for conduit) on a plurality of corrugated conduits for conduit arranged in parallel. A heat-shrinkable plastic endless belt having a width W defined by the following equation (1) is attached at each interval of length L selected from the range: W = (1/60) · L + S ( 1) (where S is (4 + ／) from (1 + ／) · P
-Any value in the range of P. Next, the heat-shrinkable plastic endless belt is heat-shrinked, and a plurality of corrugated pipe groups arranged in parallel are bundled in parallel.

The corrugated pipe to be bound in the present invention is a corrugated pipe for a conduit which is mainly formed of a material comprising a polyolefin resin. The reason is that such corrugated pipe is chemically resistant,
This is because it is excellent in weather resistance and the like and inherently flexible, and has durability against repeated fatigue caused by winding and unwinding. Particularly, the dimensions of the corrugated tube suitable for application of the present invention are as follows: when the outer diameter of the corrugated tube is D, the pitch of the corrugated tube is P, and the wave height of the corrugated tube is h, 3 ≦ D / P ≦ 10 and 9 ≦ D / h
It is a corrugated tube in the range of ≦ 15. Since the corrugated pipe in the range where the relationship between the outer diameter and the wave height and the relationship between the outer diameter and the pitch is applied has a corrugated structure having an appropriate wave height and pitch to exhibit flexibility with respect to the outer diameter. It is.

In the present invention, the heat-shrinkable plastic endless belt is used because, when heated, the heat-shrinkable plastic endless belt contracts isotropically with respect to the corrugated pipe. Because it closely adheres to the outside of the complicated wave shape,
Even in the case of a long corrugated pipe, a plurality of corrugated pipes arranged in one stage in parallel without displacing the parallel arrangement of a plurality of corrugated pipes and disturbing the parallel arrangement of the corrugated pipes. This is because the tube groups can be tightly bound in the same arrangement. A tenth embodiment of a corrugated pipe bundle for a conduit according to the first aspect of the present invention is illustratively shown in FIG. In the figure, reference numeral 12 denotes a corrugated tube which is shown only in a part of a corrugated shape for simplicity, and 14 denotes a heat-shrinkable plastic endless belt.

In the present invention, since the corrugated pipes are arranged in a single-stage parallel arrangement rather than in a bale stack, they have flexibility in a direction perpendicular to the arrangement plane (X direction in FIG. 1). Since it has rigidity in the direction including the direction (Y direction in FIG. 1), it is possible to prevent meandering of the bundle of corrugated pipes when laying. Preferably, in order not to disturb the arrangement of the corrugated tubes, a rigid flat plate 16 having a length substantially equal to the entire width of the corrugated tube group 12 arranged in parallel is corrugated, as schematically shown in FIG. An endless belt made of heat-shrinkable plastic is mounted below the tube group, that is, between the tube group 12 with wave arrangement and the endless belt made of heat-shrinkable plastic. Thereby, the parallel arrangement of the corrugated tubes is more reliably maintained.

The form of the heat-shrinkable plastic endless belt is not particularly limited as long as the corrugated tube can be wound in an annular shape. For example, a heat-shrinkable plastic tape or sheet is adhered to each end with an adhesive. The belt may be an endless belt, or may be formed in advance into an endless belt. As the heat-shrinkable plastic, products made of cross-linked polyethylene and cross-linked polyvinyl chloride are commercially available. The range of the intervals to be attached to the corrugated tube group of the heat-shrinkable plastic endless belt defined by the above formula (1) is shown in FIG.
Are the values of the width W and the binding interval L of the heat-shrinkable plastic endless belt in the area A indicated by oblique lines. In the range of A in which the width W of the endless belt and the mounting interval L of the belt are maintained in an appropriate relationship, even when the applicable corrugated pipe is a long corrugated pipe,
Its good flexibility and binding properties can be maintained. However, in the region B, the obtained corrugated tube bundle has insufficient flexibility, and in the region C, the corrugated tube group lacks the cohesiveness, so that the unity of the individual corrugated tubes is loosened. The integrity of the corrugated tube bundle cannot be maintained. Hereinafter, the present invention will be described in more detail based on embodiments with reference to the accompanying drawings.

[0012]

【Example】

Example 1 As a corrugated tube 12, a polyethylene corrugated tube Eflex (registered trademark) manufactured by Furukawa Electric Co., Ltd. has a nominal diameter of 50 (outer diameter of 6).
5mm, pitch (P) 17mm, wave height (h) 6mm) length 1
00m was used. The above three corrugated tubes 12 are arranged side by side in parallel, and a heat contraction of 30P (17 mm × 30) in the longitudinal direction, ie, 2P (17 mm × 2) every 510 mm, ie, 34 mm and 1.0 mm thick Endless belt 12 made of a flexible cross-linked polyethylene (trade name: Rapco tube (trade name, manufactured by Furukawa Electric Co., Ltd.) having a shrinkage ratio of 30 to 50%) was attached to the outer periphery of a corrugated tube group arranged in parallel. In the embodiment, as the endless belt made of heat-shrinkable plastic, a cylindrical cross-linked polyethylene tube used was a belt preformed on a pipe, but a band-shaped tape of the same material was wound, and the joint was bonded with an adhesive. Endless belt.

Next, each of the attached heat-shrinkable plastic endless belts 12 is shrunk by heating at a temperature of 140 ° C. to 180 ° C. for 2 minutes, thereby arranging the three endless belts in parallel.
Example 1 was obtained by bundling the corrugated tubes. The obtained crimped tube bundle of Example 1 is heat-shrinkable by the individual heat-shrinkable plastic endless belts 12 isotropically, and three corrugated tubes 10 are obtained.
Are united in a state of being arranged adjacently in parallel,
As a result, the integrity of the binding is ensured, and the flexibility in the direction perpendicular to the arrangement surface (X direction in FIG. 1) is maintained. The obtained corrugated tube bundle 10 of Example 1 is schematically shown in FIG. However, FIG. 1 shows five corrugated tubes 12. Further, in order to evaluate the binding property and flexibility of the crimped tube bundle of Example 1, it was tested whether the obtained crimped tube bundle could be wound into three layers with a winding diameter of 50 cm, and the evaluation results were shown. 1 is shown.

[0014]

[Table 1] In Table 1, the bundling interval L is shown at 10P intervals from 10P to 100P in the horizontal direction, and the width W of the heat-shrinkable plastic endless belt is shown at every interval P from 1P to 7P in the vertical direction, The results of the winding test at the respective L and W values are shown.

The symbol A in the table indicates that a bundle of corrugated pipes in a three-row parallel arrangement can be wound in three layers with a winding diameter of 50 cm, and the winding of the corrugated pipe bundle collapses after winding. Indicates that there was no. Accordingly, the corrugated tube bundle is bound with a satisfactory binding property, which means that the corrugated tube bundle has excellent flexibility in a direction orthogonal to the arrangement plane of the corrugated tube bundle, and the evaluation is Is good. Symbol B is 3 due to lack of flexibility.
This indicates that it was not possible to wind the bundle of corrugated tubes in a row parallel arrangement with a winding diameter of 50 cm. Further, it shows that the winding required a winding diameter of 1 m or more, and that the wound state was maintained rigidly after further winding. It means that the flexibility of the corrugated tube bundle is insufficient, and the evaluation is poor. Symbol C indicates that the bundle of the corrugated tubes was loosened during the winding of the bundle of corrugated tubes in a three-row parallel arrangement in three layers with a winding diameter of 50 cm and the winding was broken apart. I have. It means that the cohesiveness of the corrugated tube is insufficient, and the evaluation is poor.

Another Example As shown in Table 1, except that the width W and the binding interval L of the heat-shrinkable plastic endless belt 12 were variously changed within the range defined by the above-mentioned equation (1). In the same manner as in Example 1, a plurality of corrugated tubes were bound by the method of the present invention to obtain a number of examples. An evaluation test was carried out in the same manner as in Example 1, and the results are shown in Table 1.

COMPARATIVE EXAMPLE As a comparative example of the embodiment bound by the method of the present invention, as shown in Table 1, the width W and the binding interval L of the heat-shrinkable plastic endless belt 12 are also defined by the above formula (1). Example 1 except for various changes outside the range
A plurality of corrugated pipes were bound in the same manner as in Example 1 to obtain a number of comparative examples. An evaluation test was carried out in the same manner as in Example 1, and the results are shown in Table 1. Table 1 reveals that the evaluation of the example is good and the evaluation of the comparative example is bad.
It is experimentally demonstrated that the relationship between the width W of the heat-shrinkable plastic endless belt defined by the equation (1) and the binding interval L is correct.

[0018]

According to the method of the present invention, a heat-shrinkable endless belt made of plastic is used as a band for binding, and the interval between the bundles and the width of the endless belt used for the binding are determined under a binding condition defined by a specific relationship. By bundling, even in the case of a long corrugated tube, the flexibility is such that the multiple corrugated tubes arranged adjacently in parallel and arranged in one stage are freely bent integrally and in a direction perpendicular to the arrangement surface. Can be united while maintaining Accordingly, the bundle of corrugated tubes bundled by the method of the present invention can be stored in a drum-wrapped form having a small winding diameter, and is easy to store and transport. In addition, the corrugated tubes arranged in parallel in one stage are bound in the same arrangement, and have appropriate rigidity so as not to meander on the arrangement surface while maintaining flexibility in a method orthogonal to the arrangement surface. It is not necessary to disassemble the tied tube at the laying site, and the tubing can be laid while being tied. Therefore, if the corrugated pipe bundle according to the present invention is used, it is necessary to disassemble the corrugated pipe bundle as in the related art, lay individual corrugated pipes, and then fix a plurality of corrugated pipes again. It is not necessary to tie it with a belt or to fix it with a fixing plate or the like. As a result, labor and material costs can be greatly reduced and the time required for the installation can be shortened in the installation work of the protection pipe for the electric wire and the cable.

[Brief description of the drawings]

FIG. 1 is a schematic perspective explanatory view of a corrugated tube bundle for a conduit according to the present invention.

FIG. 2 is a graph illustrating a range of a width W and a binding interval L of a heat-shrinkable plastic endless belt defined by Expression (1).

FIG. 3 is an explanatory cross-sectional view showing a corrugated tube bound by a method according to another embodiment of the present invention.

FIGS. 4 (a) and 4 (b) are cross-sectional views for explanation showing a conventional bundling type bundling method of corrugated pipes.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 The embodiment of the corrugated pipe bundle for electric conduit according to the present invention 12 The corrugated pipe for electric conduit 14 Endless belt made of heat-shrinkable plastic 16 Flat plate

──────────────────────────────────────────────────続 き Continuation of the front page (72) Inventor Kazuya Imamatsu 2-6-1 Marunouchi, Chiyoda-ku, Tokyo Furukawa Electric Co., Ltd. (56) References JP 50-65394 (JP, A) Hei 4-64920 (JP, U) Actually open 49-97286 (JP, U) (58) Fields investigated (Int. Cl. ⁶ , DB name) B65B 13/00-13/34 B65B 27/00-27 / 12

Claims (2)

(57) [Claims] 1. A plurality of corrugated conduits for conduits, which are formed mainly of a polyolefin-based resin, are arranged in parallel adjacent to each other, from 30 · P to 90 · P (where P is The corrugated pitch of the corrugated tube for the conduit).
The heat-shrinkable plastic endless belt having a width W defined by the following equation (1) is provided for each length interval L selected from the following range: W = (1/60) · L + S (1) (Where S is from (1 + ／) · P to (4 + ／) ·
Any value in the range of P. 2.) A bundle of corrugated pipes for a conduit, wherein the bundles are bundled in parallel with each other. 2. A plurality of corrugated pipes for conduits, which are formed mainly of a polyolefin resin, are arranged in parallel adjacent to each other, and said plurality of corrugated pipes for conduits arranged in parallel. On the group
For each interval of length L selected from the range of 30 · P to 90 · P (where P is the corrugated pitch of the corrugated pipe for conduit), the following equation (1) An endless belt made of a heat-shrinkable plastic having a width W defined by the following formula is attached. W = (1/60) · L + S (1) (where S is (1 + ／) · P to (4 + ／))・
Any value in the range of P. Next, the heat-shrinkable endless belt made of plastic is heated and shrunk, and the plurality of corrugated pipe groups arranged in parallel are bound in parallel. Method.