JP2018035827A - Bent tube - Google Patents

Abstract

PROBLEM TO BE SOLVED: To secure pressure resistance performance and sealability at a connection part between unit pipes, in a bent pipe such as a homogeneous bent pipe.SOLUTION: Inclined end surfaces 11e of unit pipes 11 adjacent to a bent pipe body 10 of a homogeneous bent pipe 2 abut to each other. An outer surface coupling material 20 is provided so as to straddle over outer peripheral surfaces of the adjacent unit pipes 11. An inner surface coupling material 50 is provided so as to straddle over inner peripheral surfaces of the adjacent unit pipes 11. The inner surface coupling material 50 comprises two first fiber-reinforced plastic layers 51 containing a nonwoven fabric as a reinforced fiber 51a, and one or two second fiber-reinforced plastic layers 52 containing a woven fabric as a reinforced fiber 52a. The second fiber-reinforced plastic layer 52 is held between the two first fiber-reinforced plastic layers 51.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a bent tube having a bent or curved tube axis, and more particularly to a bent tube suitable for a homogeneous bent tube.

  For example, as disclosed in Patent Document 1 and the like, the homogeneous curved pipe includes a plurality of unit pipes. The end face of each unit tube is an inclined end face that is inclined with respect to its own axis. By abutting the inclined end surfaces of adjacent unit tubes, these unit tubes are joined to each other at an oblique angle. Further, a laminate is provided between the outer peripheral surfaces and the inner peripheral surfaces of these unit tubes. Each laminate is constituted by a cloth-like body impregnated with a resin. As a result, the seams between the unit tubes are sealed (sealed).

Japanese Patent Laying-Open No. 2015-140867

With respect to the inner peripheral surface of the homogeneous curved pipe, the number of laminated layers is limited in order to hinder the flow down when the thickness of the laminated body increases. In the above-mentioned patent document, a non-woven fabric such as a non-directional glass mat is used as the cloth body of the laminated body on the inner peripheral surface. For this reason, the laminated body in an inner peripheral surface cannot expect the intensity | strength as a junction part, but its pressure | voltage resistant performance is low.
In general, a homogeneous curved pipe is obtained by cutting a raw material pipe obliquely to obtain a plurality of unit pipes, and rotating one unit pipe of two adjacent unit pipes by 180 ° with respect to the other unit pipe. Thus, the cut end surfaces are brought into contact with each other and joined, but the cut surface is not always good. For this reason, a gap is easily generated in the joint portion, and it is not easy to ensure sealing properties such as water stoppage. The gap may be filled with a resin putty, but it is a manual work, so the finish varies.
An object of the present invention is to secure pressure resistance performance and sealing performance at a joint between unit tubes in a bent tube in which a plurality of unit tubes such as homogeneous bent tubes are connected.

In order to solve the above-mentioned problem, a curved pipe according to the present invention includes a curved pipe body, an outer surface connecting material, and an inner surface connecting material,
The curved pipe body includes a plurality of unit tubes, each unit tube has an inclined end surface that is inclined with respect to its own axis, and the inclined end surfaces of adjacent unit tubes are abutted against each other,
The outer surface connecting material spans between the outer peripheral surfaces of adjacent unit pipes, and connects the unit pipes.
The inner surface connecting material includes two first fiber reinforced plastic layers including nonwoven fabric as reinforcing fibers, and one or two second fibers sandwiched between the two first fiber reinforced plastic layers including woven fabric as reinforcing fibers. It has a reinforced plastic layer, and each fiber reinforced plastic layer is straddling between the inner peripheral surfaces of adjacent unit tubes.
Thereby, it is possible to ensure the pressure resistance performance and the sealing performance at the joint between the unit pipes of the curved pipe.

It is preferable that the first and second fiber reinforced plastic layers are wider toward the radially inner side of the curved pipe body.
Thereby, the center part of the width direction of an inner surface connection material can be thickened. Usually, the center part of the width direction of an inner surface connection material is located in the joint of unit pipes. Therefore, it is possible to increase the thickness of the inner surface connecting member at the joint between the unit tubes, and to sufficiently secure the pressure resistance performance and the sealing performance at the joint. Moreover, the thickness of the both sides of the width direction of an inner surface connection material can be made small in steps, and the flow in a curved pipe can be made smooth.

The second fiber reinforced plastic layer is narrower than the first fiber reinforced plastic layer on the inner peripheral surface side, and the first fiber reinforced on the radially inner side of the bent pipe body from the second fiber reinforced plastic layer. The plastic layer may be wider than the first fiber reinforced plastic layer on the inner peripheral surface side.
In the joint between the unit pipes, the inner surface connecting material is a laminated structure of the first fiber reinforced plastic layer on the inner peripheral surface side, the second fiber reinforced plastic layer, and the first fiber reinforced plastic layer on the radially inner side. By doing so, the pressure resistance performance and sealing performance at the joint can be sufficiently secured. Furthermore, material costs can be reduced by reducing the required amount by narrowing the second fiber reinforced plastic layer.

  ADVANTAGE OF THE INVENTION According to this invention, in curved pipes, such as a homogeneous curved pipe, the pressure | voltage resistant performance and sealing performance in the joint line of unit pipes are securable.

FIG. 1 is a plan view showing a main part of a homogeneous bend pipe according to the first embodiment of the present invention. FIG. 2 is a cross-sectional view of the circle II in FIG. FIG. 3 shows a second embodiment of the present invention and is a cross-sectional view corresponding to FIG. FIG. 4 shows a third embodiment of the present invention and is a cross-sectional view corresponding to FIG.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
<First Embodiment>
1 and 2 show a first embodiment of the present invention. As shown in FIG. 1, the homogeneous curved pipe 2 (curved pipe) is provided as a sewer pipe or an agricultural water pipe, for example. The homogeneous curved pipe 2 is obtained by, for example, cutting a raw material pipe obliquely to obtain a plurality of unit pipes 11 and rotating one unit pipe 11 of two adjacent unit pipes 11 with respect to the other unit pipe 11 by 180 °. Then, the cut end faces 11e are brought into contact with each other and connected. As a result, the tube axis of the homogeneous bent tube 2 is bent at a predetermined angle.

  Specifically, the homogeneous bent pipe 2 includes a bent pipe body 10 and an outer surface connecting member 20. The curved tube body 10 includes a plurality of unit tubes 11 (only three are shown in FIG. 1). Each unit pipe 11 and the bent pipe body 10 are constituted by a hard resin pipe such as a fiber reinforced plastic pipe (FRP pipe) or a fiber reinforced plastic composite pipe (FRPM pipe). The FRP tube and the FRPM tube may be produced by a filament winding molding method.

  As shown in FIG. 1, a plurality of unit tubes 11 are connected in a row. At least one end surface 11 e of each unit tube 11 is inclined with respect to the axis of the unit tube 11. The inclined end surfaces 11e of the adjacent unit tubes 11 are abutted against each other.

  Outer surface connecting members 20 are arranged between adjacent unit tubes 11 in the curved tube body 10. The outer surface connecting member 20 is made of fiber reinforced plastic (FRP). Specifically, as shown in FIG. 2, the outer surface connecting member 20 includes a cloth-like body 21 (reinforced fiber) and a filling resin 22. Examples of the material of the cloth-like body 21 include glass fibers, carbon fibers, and aramid fibers. The cloth-like body 21 may be a woven cloth such as a roving cloth, or may be a non-woven cloth (non-directional cloth-like body) such as a glass mat. The cloth-like body 21 in FIG. 2 is schematically shown for convenience of drawing. Filling resin 22 is impregnated in cloth-like body 21. Examples of the component of the filling resin 22 include an unsaturated polyester resin, an epoxy resin, and a vinyl ester resin.

  As shown in FIG. 1, the outer surface connecting member 20 spans between outer peripheral surfaces of adjacent unit tubes 11 and is wound in an annular shape in the circumferential direction of each unit tube 11. The filling resin 22 is bonded to the bent tube body 10 by adhesiveness at the time of application or uncured. Adjacent unit tubes 11 are connected to each other through the outer surface connecting member 20. In the outer peripheral portion 2o of the homogeneous bent pipe 2, the adjacent outer surface connecting members 20 are separated from each other. In the inner peripheral part 2i of the homogeneous curved pipe 2, the adjacent outer surface connecting members 20 are closer to each other than the outer peripheral part 2o. In the inner peripheral portion 2i, the adjacent outer surface connecting members 20 may be slightly overlapped or connected to each other.

  The thickness of the outer surface connecting member 20 or the number of layers of the cloth-like body 21 is set according to the required pressure resistance of the homogeneous bent pipe 2 or the like. The required pressure resistance (internal pressure) of the homogeneous curved pipe 2 is, for example, about 0.5 MPa. If a higher pressure resistance is required, it can be dealt with by increasing the number of laminated layers of the cloth-like body 21.

  As shown in FIG. 2, generally in a homogeneous curved pipe, there may be a gap 10e between the unit pipes 11 due to cutting accuracy of the inclined end surface 11e of the unit pipe 11 or deformation due to its own weight. In that case, the outer surface connecting member 20 can close the gap 10e from the outer peripheral side.

  Furthermore, in the homogeneous curved pipe 2 of the embodiment of the present invention, an inner surface connecting member 50 is provided on the inner periphery of the curved pipe body 10 as shown in FIG. The inner surface connecting member 50 includes two first fiber reinforced plastic layers 51 and one second fiber reinforced plastic layer 52. The first fiber reinforced plastic layer 51 includes a nonwoven fabric 51a (reinforced fiber) and a first filling resin 51b. As the nonwoven fabric 51a, for example, a non-directional glass fiber cloth (mat, surface mat, etc.) is used. Instead of glass fibers, carbon fibers or aramid fibers may be used. The nonwoven fabric 51a in FIG. 2 is schematically illustrated for convenience of drawing. The nonwoven fabric 51a is impregnated with the first filling resin 51b. Examples of the component of the first filling resin 51b include unsaturated polyester resins, epoxy resins, vinyl ester resins, and the like.

  The second fiber reinforced plastic layer 52 includes a woven fabric 52a (reinforced fiber) and a second filling resin 52b. As the woven fabric 52a, for example, a glass fiber fabric (roving cloth, glass cloth, etc.) is used. Instead of glass fibers, carbon fibers or aramid fibers may be used. The woven fabric 52a in FIG. 2 is schematically illustrated for convenience of drawing. The woven fabric 52a is impregnated with the second filling resin 52b. Examples of the component of the second filling resin 52b include an unsaturated polyester resin, an epoxy resin, and a vinyl ester resin.

  Each of the fiber reinforced plastic layers 51 and 52 has an annular shape along the circumferential direction of the inner peripheral surface of the bent tube body 10. A first fiber reinforced plastic layer 51 of the first layer (upper side in FIG. 2) is directly laminated on the inner peripheral surface of the unit tube 11. A second fiber reinforced plastic layer 52 is laminated on the first first fiber reinforced plastic layer 51. Another (third) first fiber reinforced plastic layer 51 is laminated on the second fiber reinforced plastic layer 52. Accordingly, one second fiber reinforced plastic layer 52 is sandwiched between the two first fiber reinforced plastic layers 51.

  The fiber reinforced plastic layers 51 and 52 straddle between the inner peripheral surfaces of the adjacent unit tubes 11. As a result, the inner surface connecting material 50 straddles between the inner peripheral surfaces of the adjacent unit tubes 11. The first fiber reinforced plastic layer 51 of the first layer is bonded to the curved pipe body 10 by the adhesiveness when the filling resins 51b and 52b are applied or uncured, and the fiber reinforced plastic layers 51 and 52 are bonded to each other. Has been.

The first and second fiber reinforced plastic layers 51 and 52 are wider toward the radially inner side (lower side in FIG. 2) of the bent tube body 10. That is, the width W ₅₂ of the second (intermediate) second fiber reinforced plastic layer 52 is larger than the width W ₅₁ of the first fiber reinforced plastic layer 51 of the first layer (inner peripheral surface side of the bent tube body 10). Large (W ₅₂ > W ₅₁ ). Both ends of the second fiber reinforced plastic layer 52 in the width direction (left and right in FIG. 2) extend beyond the first fiber reinforced plastic layer 51 of the first layer. The width W ₅₃ of the third first fiber reinforced plastic layer 51 is larger than the width W ₅₂ of the second second fiber reinforced plastic layer 52 (W ₅₃ > W ₅₂ ). Both end portions in the width direction (left and right in FIG. 2) of the third first fiber reinforced plastic layer 51 extend beyond the second fiber reinforced plastic layer 52. As a whole, the inner surface connecting member 50 has a thick central portion in the width direction and gradually thins both side portions in the width direction.
For example, W ₅₁ = about 150 mm, W ₅₂ = about 200 mm, and W ₅₃ = about 250 mm, but the present invention is not limited to this.

According to the homogeneous curved pipe 2, adjacent unit pipes 11 can be connected from the outer peripheral side by the outer surface connecting member 20, and can also be connected from the inner peripheral side by the inner surface connecting member 50. Thereby, the connection strength of the unit tubes 11 can be increased. As a result, the pressure resistance performance with respect to the internal pressure of the homogeneous bent pipe 2 can be improved.
Further, when the gap 10e is formed at the joint between the unit pipes 11, not only the outer surface connecting member 20 can block the gap 10e from the outer peripheral side, but also the inner surface connecting member 50 can block the gap 10e from the outer peripheral side. it can. Thereby, the water tightness (sealing property) at the joint between the unit pipes 11 can be secured. In particular, by sandwiching the second fiber reinforced plastic layer 52 between the two first fiber reinforced plastic layers 51, sufficient watertightness can be ensured. As a result, the water stoppage (sealability) of the homogeneous bent tube 2 can be enhanced.

Conventionally, when the gap 10e is generated, it is closed with a resin putty. However, the strength of the putty itself cannot be expected, and the finish tends to vary due to manual work.
On the other hand, according to the homogeneous bent pipe 2, the strength of the inner surface connecting member 50 can be increased by sandwiching the second fiber reinforced plastic layer 52 between the two first fiber reinforced plastic layers 51, and consequently the unit. The connection strength between the tubes 11 can be increased. Further, by increasing the thickness of the central portion in the width direction of the inner surface connecting member 50, it is possible to sufficiently ensure the pressure resistance performance and sealing performance at the joint, and stepwise the thickness of both side portions of the inner surface connecting member 50 in the width direction. By making it small, smoothness can be obtained, and fluid such as water can flow smoothly in the homogeneous bent tube 2.

Next, another embodiment of the present invention will be described. In the following embodiments, the same reference numerals are given to the drawings for the same configurations as those already described, and the description thereof is omitted.
Second Embodiment
FIG. 3 shows a second embodiment of the present invention. In the inner surface connecting member 50B of the second embodiment, the width W ₅₂ of the second (intermediate) second fiber reinforced plastic layer ₅₂ is the first layer (the inner peripheral surface side of the bent tube body 10, the upper side in FIG. 3). ) Smaller than the width W ₅₁ of the first fiber-reinforced plastic layer 51 (W ₅₂ <W ₅₁ ). The width W ₅₃ of the first fiber reinforced plastic layer 51 in the third layer (in the radial direction, the lower side in FIG. 3) is larger than the width W ₅₁ of the first fiber reinforced plastic layer 51 in the first layer (W ₅₃ > W ₅₁ ).
For example, W ₅₁ = about 150 mm, W ₅₂ = about 100 mm, and W ₅₃ = about 250 mm, but the present invention is not limited to this.

The narrow second fiber reinforced plastic layer 52 is disposed so as to straddle between the adjacent unit tubes 11. In the vicinity of the seam between the unit tubes 11, the first first fiber reinforced plastic layer 51, the second second fiber reinforced plastic layer 52, and the third first fiber reinforced plastic layer 51, It has a three-layer structure. Therefore, it is possible to sufficiently ensure the water tightness at the joint between the unit pipes 11. In addition, the connection strength between the unit tubes 11 can be secured.
Furthermore, since the required amount of the second fiber reinforced plastic layer 52 is reduced, the material cost can be reduced.

<Third Embodiment>
FIG. 4 shows a third embodiment of the present invention. In the third embodiment, the inner surface connecting member 50 </ b> C includes two first fiber reinforced plastic layers 51 and two second fiber reinforced plastic layers 52. The first fiber reinforced plastic layer 51 of the first layer (upper side in FIG. 4) is directly laminated on the inner peripheral surface of the unit tube 11. A second fiber reinforced plastic layer 52 of the second layer is laminated on the first fiber reinforced plastic layer 51 of the first layer. Another (third layer) second fiber reinforced plastic layer 52 is laminated on the second layer second fiber reinforced plastic layer 52. Another (fourth) first fiber reinforced plastic layer 51 is laminated on the third second fiber reinforced plastic layer 52.
According to the third embodiment, by forming the inner surface connecting member 50C into a four-layer structure, the water tightness at the joint between the unit tubes 11 can be further increased, and further, the connection strength between the unit tubes 11 is further increased. be able to.

The present invention is not limited to the above embodiment, and various modifications can be made without departing from the spirit of the present invention.
For example, two or more first fiber reinforced plastic layers 51 and two or more second fiber reinforced plastic layers 52 may be alternately stacked. The widths of the first and second fiber reinforced plastic layers 51 and 52 may be equal to each other.
The present invention is not limited to a homogeneously bent tube, and can be applied to various bent or bent tubes.

  The present invention can be applied to, for example, sewer pipes and agricultural water pipes.

2 Homogeneous curved pipe (curved pipe)
2i Inner circumference part 2o Outer circumference part 10 Curved pipe body 10e Gap 11 Unit pipe 11e Inclined end face 20 Outer surface connection material 21 Cloth-like body 22 Filling resin 50, 50B, 50C Inner surface connection material 51 First fiber reinforced plastic layer 51a Non-woven fabric (reinforced) fiber)
51b 1st filling resin 52 2nd fiber reinforced plastic layer 52a Woven cloth (reinforced fiber)
52b Second filling resin

Claims (3)

A curved pipe body, an outer surface connecting material, and an inner surface connecting material,
The curved pipe body includes a plurality of unit tubes, each unit tube has an inclined end surface that is inclined with respect to its own axis, and the inclined end surfaces of adjacent unit tubes are abutted against each other,
The outer surface connecting material spans between the outer peripheral surfaces of adjacent unit pipes, and connects the unit pipes.
The inner surface connecting material includes two first fiber reinforced plastic layers including nonwoven fabric as reinforcing fibers, and one or two second fibers sandwiched between the two first fiber reinforced plastic layers including woven fabric as reinforcing fibers. A curved pipe having a reinforced plastic layer, and each fiber reinforced plastic layer straddling between inner peripheral surfaces of adjacent unit pipes.   The curved pipe according to claim 1, wherein the first and second fiber reinforced plastic layers are wider toward the radially inner side of the curved pipe body. The second fiber reinforced plastic layer is narrower than the first fiber reinforced plastic layer on the inner peripheral surface side;
The first fiber reinforced plastic layer radially inward of the bent pipe body with respect to the second fiber reinforced plastic layer is wider than the first fiber reinforced plastic layer on the inner peripheral surface side. The curved pipe described.

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