JP2003014165A - Fluid transferring plastic pipe - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a fluid transferring plastic pipe having high tensile strength and durability against a load concentrated to one point without hindering the original flexibility of the plastic pipe. SOLUTION: This fluid transferring plastic pipe 10 is formed by arranging a reinforcing layer 30, which is formed by winding a belt-like sheet 3 formed of a lot of multi-filament yarns 5 at 30 degree or less against the pipe axial direction, and a reinforcing layer 40, which is formed by winding a metal wire 4 at 85 degree or more and less than 90 degree against the pipe axial direction, between plastic pipe main bodies 1 and 2.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a plastic pipe used for fluid transfer, and more particularly to a plastic pipe for fluid transfer suitable as a deep water intake pipe.

[0002]

2. Description of the Related Art In recent years, it has been found that "deep water" existing in the deep sea at a depth of 300 m or more contains a large amount of minerals, and when this deep water is used for drinking water, food processing water, lotion, etc. It has been shown to exert excellent effects on maintenance and beauty. For such deep water intake, a pipe is laid down to the deep sea, and a plastic pipe made of polyethylene or the like which is lightweight and easy to handle is often used as the conduit.

However, since the plastic pipe itself has a low tensile strength, if it is used as it is, it may be broken by a tensile load. In addition, it is weak against a local one-point concentrated load received on the side of the pipe. For example, if a plastic pipe is laid over a protrusion or if it is laid over a corner where the slope changes abruptly, the protrusion or corner There is a risk of breaking due to a one-point concentrated load received from the part. Therefore, a plastic pipe reinforced with a reinforcing material is used.

Conventionally, as a countermeasure against the above-mentioned tensile strength and a countermeasure against a one-point concentrated load, a metal wire (steel wire) is inserted around the outer layer of a plastic pipe so as to be wound at an angle of 15 ° to 20 ° with respect to the pipe axis direction. However, this measure has a problem that the flexibility of the plastic pipe is remarkably reduced because the metal wire having a large elastic modulus (rigidity) is used, and the workability of laying is remarkably reduced.

[0005]

SUMMARY OF THE INVENTION An object of the present invention is to provide a plastic pipe for fluid transfer which has high tensile strength and resistance to a one-point concentrated load without impairing the original flexibility of the plastic pipe. is there.

[0006]

In order to achieve the above object, the plastic pipe for fluid transfer of the present invention is a plastic pipe main body having a strip-shaped sheet in which a large number of multifilament yarns are arranged in the axial direction of the pipe. Reinforcing layer wound at less than 90 ° and metal wire in the axial direction of 85 ° to 90 °
It is characterized in that a reinforcing layer wound below is arranged.

As described above, since the reinforcing layer of the strip-shaped sheet is composed of the multifilament yarn, it does not substantially reduce the flexibility of the plastic pipe, and at a loose angle of 30 ° or less with respect to the pipe axis direction. Because it is wrapped, it gives high tensile strength to the plastic pipe. Further, when the one-point concentrated load is applied to the side surface of the pipe, the reinforcing layer of the strip-shaped sheet generates a high tension in the axial direction, and the component force in the vertical direction provides resistance to the one-point concentrated load.

Further, since the metal wire reinforcing layer has high rigidity, the metal pipe is further strengthened by giving the plastic pipe a great resistance against the above-mentioned one-point concentrated load.
Since it is wound at a high angle of 5 ° or more and less than 90 °, it is possible to maintain flexibility without increasing bending resistance of the plastic pipe.

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION In the present invention, a strip-shaped sheet has a structure in which a large number of high-strength, high-modulus multifilament yarns are aligned and arranged in a strip shape. The multifilament yarn may be untwisted or twisted, but it is preferable that the multifilament yarn is untwisted because the tenacity factor can be increased. Further, in the belt-shaped sheet, it is preferable that a large number of multifilament yarns are bound to each other by connecting yarns (weft yarns) or adhesive sheets in order to stabilize the shape.

The strip-shaped sheet may be arranged as a reinforcing layer on the inner layer of the tube body or on the outer side of the tube body. Preferably, the inner layer is not damaged by rubbing against external obstacles. In particular, when the pipe body is composed of a plastic conduit and a plastic covering layer on the outside thereof, it is preferable to arrange it between the conduit and the covering layer. When inserting between the conduit and the coating layer in this way,
The reinforcing layer of the strip-shaped sheet may be fused or adhered between the conduit and the covering layer, or may be slidable circumferentially between the conduit and the covering layer without being fused or adhered. .

The reinforcing layer of the strip-shaped sheet is formed by winding the strip-shaped sheet at a gentle angle of 30 ° or less with respect to the tube axis direction. The lower limit of the winding angle is not particularly limited, but preferably about 3 °. A more preferable winding angle is in the range of 5 ° to 20 °.

As for the method of winding the strip-shaped sheet, only one strip may be continuously wound in a spiral shape, or a plurality of strip-shaped sheets may be aligned and wound in a so-called multi-winding manner. Good. Further, when winding the strip-shaped sheets, a gap may be interposed between the side edges of the adjacent strip-shaped sheets, but it is preferable that the side edges are closely adhered or slightly overlapped and tightly wound. Is good.

The number of winding layers of the reinforcing layer of the strip-shaped sheet may be one, but it may be plural. In particular, when a plurality of reinforcing layers of the strip-shaped sheet are arranged, it is preferable that the winding directions of the strip-shaped sheets are opposite to each other with the tube axis direction sandwiched therebetween. In this way, by twisting the strip-shaped sheets in mutually opposite directions in the plurality of reinforcing layers, twisting of the plastic pipe can be prevented.

In the present invention, the type of metal wire used for the reinforcing layer of the metal wire is not particularly limited as long as it is made of a metal material having a higher tensile strength and elastic modulus than a fiber material, but steel is preferred. Use a wire (iron wire). Further, the form of the metal wire may be a single wire structure or a twisted wire (cord) obtained by twisting a plurality of thin single wires. The former single wire structure is preferable.

The metal wire reinforcing layer is formed by winding the metal wire at a high angle of 85 ° or more and less than 90 ° with respect to the tube axis direction. If the winding angle is smaller than 85 °, the flexibility of the plastic pipe is lowered, and the work of laying the plastic pipe is deteriorated. Also,
Winding at 90 ° is logically impossible for a continuous spiral winding of metal wire.

The metal wire may have a circular cross section or a non-circular cross section such as a rectangular cross section or a polygonal cross section. Although the thickness of the metal wire depends on the size of the plastic pipe to be reinforced, the diameter of the metal wire is preferably in the range of 3 to 15 mm in both the single wire structure and the stranded wire structure. If the thickness of the metal wire is smaller than 3 mm, it becomes difficult to give resistance to a one-point concentrated load. If it is thicker than 15 mm, the flexibility of the plastic pipe is reduced.

The thickness of a metal wire having a non-circular cross section is regarded as the diameter of the non-circular cross-section metal wire, with the diameter of the circle converted into a circle having the same cross-sectional area.

As for the method of winding the metal wire, only one wire may be continuously wound in a spiral shape, or a plurality of wires may be aligned and wound in a so-called multi-winding manner. It is preferable to continuously wind one metal wire as in the former case, since the influence on the decrease in flexibility of the plastic pipe can be reduced. Further, since the metal wire imparts resistance to a one-point concentrated load, it is desirable that the metal wire be closely wound so as not to form a gap between the metal wires. When opening the gap, it is preferable to set the upper limit to 1/3 of the diameter of the metal wire.

In the plastic pipe for fluid transfer of the present invention, both the reinforcing layer of the strip-shaped sheet and the reinforcing layer of the metal wire are combined and arranged in the plastic pipe body. The mutual positional relationship with the reinforcing layer may be such that the reinforcing layer of the strip sheet is inside and the reinforcing layer of the metal wire is outside, or conversely, the reinforcing layer of the metal wire is inside and the reinforcing layer of the strip sheet is outside. It may be the one that has been done.

Of the above-mentioned two types of reinforcing layers, the reinforcing layer of the strip-shaped sheet is formed by arranging the strip-shaped sheet made of a plurality of multifilament yarns at a gentle angle with respect to the pipe axis direction. Strengthens direction and strengthens tensile strength. Further, since the multi-filament yarns are arranged at a gentle angle in the tube axis direction in the reinforcing layer of the strip-shaped sheet, when a one-point concentrated load is applied to the side surface of the pipe, a large tension is generated in the axial direction, Since the vertical component of the tension resists a one-point concentrated load, 1
It is also possible to create resistance to point concentrated loads. The reinforcing layer of the strip-shaped sheet has a fiber as a basic structure while having such an effect, and therefore does not significantly increase the bending resistance of the plastic pipe and does not deteriorate the flexibility.

On the other hand, since the metal wire reinforcing layer is wound with a metal wire having a large rigidity, the resistance against the one-point concentrated load acting on the side surface of the pipe is larger than that of the belt-like sheet reinforcing layer. It shows strength and is highly resistant to plastic pipes. However, the reinforcement layer of this metal wire is
Since the metal wire is wound at a high angle of 85 ° or more and less than 90 ° with respect to the tube axis direction, the bending resistance of the plastic pipe is not increased, and therefore the flexibility is not significantly reduced.

A detailed description will be given below with reference to the embodiment shown in the drawings.

1 (A) and 1 (B) illustrate a plastic pipe for fluid transfer of the present invention.

As shown in FIG. 1, a plastic pipe 1
Reference numeral 0 denotes a pipe body composed of a plastic conduit 1 and a plastic covering layer 2, and between the conduit 1 and the covering layer 2, a reinforcing layer 30 of a strip-shaped sheet 3 and a reinforcing layer 40 of a metal wire 4 are provided. Are arranged. The reinforcing layer 30 is formed by winding the strip-shaped sheet 3 so that the side edges are in close contact with each other at the winding angle α with respect to the tube axis direction. In addition, the reinforcing layer 40
Are formed by winding the metal wire 4 so as to be in close contact with each other at a winding angle β with respect to the tube axis direction.

The wrapping angle α of the band-shaped sheet 3 is set to 30 ° or less, preferably 3 ° to 30 °, more preferably 5 ° to 20 °. By setting the wrapping angle α as described above, the tensile strength of the plastic pipe 10 in the pipe axis direction is strengthened, and at the same time, resistance to a one-point concentrated load on the side surface of the pipe is given. The winding angle β of the metal wire 4 is set to 85 ° or more and less than 90 °. By setting the winding angle β in this way, the resistance to the one-point concentrated load is further enhanced without significantly reducing the flexibility of the plastic pipe 10. In addition, the reinforcing layer 40 of the metal wire 4
Has a large specific gravity, so it also serves as a weight,
Improves workability when the plastic pipe 10 is used for deep water intake.

In the plastic pipe 10 of the present invention, a protective tape made of a fabric such as a non-woven fabric may be spirally wound around the outer periphery of the conduit 1, or the non-woven fabric and / or the resin film may be wrapped around the outer periphery of the belt-shaped sheet 3 as required. The holding tape made of may be spirally wound.

As the strip-shaped sheet 3 used for reinforcing the plastic pipe 10, as shown in FIG. 2, a large number of multifilament yarns 5 are arranged in parallel at a small interval, and the multifilament yarns 5 are arranged between them. It is preferable that the connection yarns 7 (weft yarns) are connected at predetermined intervals in the longitudinal direction. For the multifilament yarn 5, an organic fiber or a nonmetallic inorganic fiber having high strength and high elastic modulus is used.

As a means for restraining the multifilament yarns 5 from one another, the connecting yarn 7 as described above is used, and as shown in FIG. 3, a resin sheet or a non-woven fabric coated with an adhesive on one side is used. Sheet 8 may be used. In the strip-shaped sheet 3 of FIG. 3, a large number of multifilament yarns 5 are adhered to the surface of the resin sheet or the non-woven fabric sheet 8 on which the adhesive is applied so as to be arranged in parallel. When using such an adhesive sheet, as shown in FIG. 4, another resin sheet or non-woven fabric sheet 8 with an adhesive is covered with the adhesive-coated surface side of the two resin sheets or non-woven fabric sheet 8. , 8 may be sandwiched between them.

In the plastic pipe of the present invention, the resin used for the conduit or the coating layer constituting the pipe body is not particularly limited, but thermoplastic resins such as polyethylene, polypropylene, polyamide and polyester are preferable. Among them, polyethylene is particularly preferable.

The multifilament yarn used for the band-shaped sheet is not particularly limited as long as it has high tenacity and high elastic modulus. Preferably, the strength is 900 MPa or more and the elastic modulus is 35 GPa.
Or more, more preferably 15,000 MPa or more,
It is preferable to use an organic fiber or a nonmetallic inorganic fiber having an elastic modulus of 450 GPa or more.

Specifically, as the organic fiber multifilament yarn, a para-type wholly aromatic polyamide fiber and poly-P are used.
-Phenylene benzbisoxazole fiber (PBO fiber) and the like are preferable. Further, as the non-metallic inorganic fiber multifilament yarn, glass fiber, carbon fiber and the like are preferable.

The fineness of the multifilament yarn is not particularly limited, but preferably 20,000 to 1,00.
It is preferable to use one having a range of 10,000 dtex.

The multifilament yarn used in the present invention is preferably used in a state where it is not impregnated with a resin such as a thermosetting resin as in a conventional prepreg. With such a resin-non-impregnated structure, not only can the cost be reduced, but the winding operation of the strip-shaped sheet can be facilitated and the handleability can be improved. It can also contribute to the flexibility of the plastic pipe.

Although the plastic pipe of the present invention is generally used for liquid transfer, it is particularly suitable for use as a deep water intake pipe.

[0035]

As described above, according to the present invention, a reinforcing layer obtained by winding a strip-shaped sheet in which a large number of multifilament yarns are arranged at an angle of 30 ° or less with respect to the tube axis direction, and a metal wire in the tube axis direction. On the other hand, by arranging a reinforcing layer wound around 85 ° or more and less than 90 °, for fluid transfer with high tensile strength and durability against one-point concentrated load without impairing the original flexibility of the plastic pipe. You can get a plastic pipe.

[Brief description of drawings]

FIG. 1 illustrates a liquid transfer plastic pipe of the present invention, in which (A) is a side view showing each layer in a broken manner, and (B) is a cross-sectional view.

FIG. 2 is a partial perspective view illustrating a strip-shaped sheet used in the present invention.

FIG. 3 is a partial perspective view illustrating another strip-shaped sheet used in the present invention.

FIG. 4 is a partial perspective view illustrating still another strip-shaped sheet used in the present invention.

[Explanation of symbols]

1 conduit 2 coating layer 3 strip sheets 30 Reinforcing layer (of strip) 4 metal wires 40 (metal wire) reinforcement layer 5 multifilament yarn 10 plastic pipes

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Kazuyuki Kudo             843-18 Kasugaura, Oita-shi, Oita-shi, Oita Prefecture             Mitsui Metal Engineering Co., Ltd. Oita             Inside the office (72) Inventor Shoji Kawano             843-18 Kasugaura, Oita-shi, Oita-shi, Oita Prefecture             Mitsui Metal Engineering Co., Ltd. Oita             Inside the office (72) Inventor Masahiro Sato             843-18 Kasugaura, Oita-shi, Oita-shi, Oita Prefecture             Mitsui Metal Engineering Co., Ltd. Oita             Inside the office F-term (reference) 3H111 AA02 BA15 BA25 BA29 BA34                       CA52 CB05 CC03 CC18 CC19                       DA26 DB02                 4F100 AB01C AB03 AK01A AK04                       AK47B AK80B AR00D BA03                       BA04 BA06 BA10A BA10D                       DA11 DG04B DG04C EH51                       GB90 JK02 JK02B JK07B                       JK17 JL00 YY00B YY00C

Claims (8)

[Claims] 1. A reinforcing layer obtained by winding a strip-shaped sheet in which a large number of multifilament yarns are arranged on a plastic pipe main body at an angle of 30 ° or less with respect to the pipe axial direction, and a metal wire in the pipe axial direction 85. A plastic pipe for fluid transfer, in which a reinforcing layer wound at an angle of not less than 90 ° and less than 90 ° is arranged. 2. The pipe body according to claim 1, wherein the pipe body comprises an inner conduit and an outer covering layer, and a reinforcing layer of the strip-shaped sheet and a reinforcing layer of a metal wire are arranged between the conduit and the covering layer. The plastic pipe for fluid transfer described. 3. The fluid transfer plastic pipe according to claim 1, wherein the reinforcing layer of the strip-shaped sheet is formed by winding the side edges of the strip-shaped sheet so as to interpose a gap therebetween. 4. The fluid transfer plastic pipe according to claim 1, wherein the reinforcing layer of the strip-shaped sheet is formed by winding the side edges of the strip-shaped sheet so as to be in close contact with or overlap with each other. 5. The reinforcing layer of the strip-shaped sheet is composed of at least two layers in which at least two strip-shaped sheets are spirally wound in directions opposite to each other with the tube axis direction sandwiched therebetween. The plastic pipe for fluid transfer according to any one of claims. 6. The strength of the multifilament yarn is 90.
The fluid transfer plastic pipe according to any one of claims 1 to 5, wherein the plastic pipe has a modulus of 0 MPa or more and an elastic modulus of 35 GPa or more. 7. The plastic pipe for fluid transfer according to claim 6, wherein the multifilament yarn is a para-type wholly aromatic polyamide fiber or poly-P-phenylenebenzbisoxazole fiber. 8. The method according to claim 1, which is used for a deep water intake pipe.
7. The plastic pipe for fluid transfer according to any one of 7.