Piping Materials

Abstract

To provide a piping member comprising a pipe part where resin pipes are fused with each other, and having no large difference in an orientation direction of fibers between the resin pipes and a fusion part.SOLUTION: A piping member 10 comprises a resin pipe part 1 having a fiber-containing layer, and a joint part 2 joined to the pipe part 1. The pipe part 1 has a first pipe part 11, a second pipe part 12, and a fusion part 3 formed between the first pipe part 11 and the second pipe part 12. The orientation of the fibers contained in the fiber-containing layer in the pipe part 1 in a longitudinal direction is tilted with respect to a pipe axis O1 direction of the pipe part 1 in the plan view of the pipe part 1.SELECTED DRAWING: Figure 1

Description

[Technical field]

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

[0002] Metal pipes and plastic pipes are used as components of piping. Plastic pipes are less susceptible to corrosion and have superior durability compared to metal pipes. Among piping, fire piping connecting water tanks and fire hydrants, fire piping connecting water tanks and sprinklers, and plant piping installed in factories, etc., require water to flow at high pressure and at a large flow rate when in use. For this reason, studies are being conducted on ways to increase the flow rate in plastic pipes and to improve the pressure resistance of plastic pipes.

[0003] A technology is known in which a fitting that is integrated with a long plastic pipe is provided at the end of the plastic pipe in advance, and then the fitting can be simply connected to the end of another pipe (plastic pipe or metal pipe), thereby joining pipes and sealing the water (see, for example, Patent Documents 1 and 2). The plastic pipe and the fitting provided at the end of the plastic pipe are mainly joined by butt fusion. Furthermore, in order to increase the strength of the resin pipe, the resin pipe may contain fibers. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Patent No. 5150190 [Patent Document 2] Design Registration No. 1552271 Summary of the Invention [Problem to be solved by the invention]

[0005] However, when the resin pipe contains fibers, the following problems arise when fusing the resin pipes together. If the fibers contained in the plastic pipe are oriented in the axial direction of the plastic pipe (X direction), when the plastic pipes are fused together, the resin flows in the direction perpendicular to the pipe axis (Y direction) at the fused part, so the fibers are also oriented in the direction perpendicular to the pipe axis (Y direction). As a result, the orientation of the fibers changes significantly between the plastic pipe and the fused part, which can reduce the strength of the fused part.

[0006] In addition, the fibers oriented in the direction perpendicular to the tube axis (Y direction) at the fused portion promoted the flow of resin in the direction perpendicular to the tube axis, which sometimes caused the bead formed on the inner surface of the fused portion to protrude more than necessary.

[0007] The present invention has been made in consideration of the above-mentioned circumstances, and aims to provide a piping component that has a pipe section in which plastic pipes are fused together, and in which there is no significant difference in the orientation direction of the fibers between the plastic pipes and the fused section. [Means for solving the problem]

[0008] In order to solve the above problems, the present invention has the following aspects. [1] A piping member comprising a resin pipe portion having a fiber-containing layer and a joint portion joined to the pipe portion, The tube portion includes a first tube portion, a second tube portion, and a fusion portion formed between the first tube portion and the second tube portion, A piping member, wherein a longitudinal direction of the fibers contained in the fiber-containing layer in the tubular portion is inclined with respect to a tubular axis direction of the tubular portion in a plan view of the tubular portion. [2] The piping component according to [1], wherein the pipe portion has an innermost layer made of a polyolefin resin. [3] The piping component according to [1], wherein the pipe portion has an outermost layer made of a polyolefin resin. [4] The piping member according to [1], wherein the pipe portion has an innermost layer made of a polyolefin resin and an outermost layer made of a polyolefin resin. [5] The piping component according to any one of [1] to [4], wherein the joint portion is a mechanical joint. Effect of the Invention

[0009] According to the present invention, it is possible to provide a piping member including a pipe portion in which resin pipes are fused to each other, in which there is little difference in the orientation direction of the fibers between the resin pipes and the fused portion. [Brief description of the drawings]

[0010] [Figure 1] 1 is a cross-sectional view of a piping member according to an embodiment of the present invention taken along a pipe axis direction of the piping member. [Diagram 2] FIG. 2 is a side view showing a schematic view of a piping member according to an embodiment of the present invention. [Diagram 3] 1 is a cross-sectional view showing a piping member according to an embodiment of the present invention, taken along a line perpendicular to a pipe axis of the piping member; [Figure 4] 1 is a cross-sectional view showing a piping member according to an embodiment of the present invention, taken along a line perpendicular to a pipe axis of the piping member; [Diagram 5] 1 is a cross-sectional view showing a piping member according to an embodiment of the present invention, taken along a line perpendicular to a pipe axis of the piping member; [Figure 6] 1 is a cross-sectional view showing a piping member according to an embodiment of the present invention, taken along a line perpendicular to a pipe axis of the piping member; [Figure 7] 1 is a cross-sectional view showing a piping member according to an embodiment of the present invention, taken along a line perpendicular to a pipe axis of the piping member; [Figure 8] 1 is a cross-sectional view of a piping member according to an embodiment of the present invention taken along a pipe axis direction of the piping member. [Figure 9] 1 is a cross-sectional view of a piping member according to an embodiment of the present invention taken along a pipe axis direction of the piping member. [Figure 10] 5A to 5C are cross-sectional views showing a method for manufacturing a piping member according to an embodiment of the present invention. [Figure 11] 5A to 5C are cross-sectional views showing a method for manufacturing a piping member according to an embodiment of the present invention. [Figure 12] 5A to 5C are cross-sectional views showing a method for manufacturing a piping member according to an embodiment of the present invention. [Figure 13]1 is a cross-sectional view of a piping member according to an embodiment of the present invention taken along a pipe axis direction of the piping member. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] [Piping components] Hereinafter, a piping member according to an embodiment of the present invention will be described with reference to the drawings. Fig. 1 is a cross-sectional view of a piping member according to an embodiment of the present invention taken along a pipe axis direction of the piping member. Fig. 2 is a side view of the piping member according to an embodiment of the present invention. The piping member 10 shown in Fig. 1 includes a pipe portion 1 and a joint portion 2. The piping member 10 has a pipe axis O1, and has a flow path 20 therein. The pipe section 1 is made of resin. The pipe section 1 has a first pipe section 11, a second pipe section 12, and a fusion section 3 formed between the first pipe section 11 and the second pipe section 12. That is, the pipe section 1 is a fusion pipe in which the first pipe section 11 and the second pipe section 12 are joined by fusion through the fusion section 3. In other words, the pipe section 1 is a resin pipe connector in which the first pipe section 11 and the second pipe section 12 are integrated by fusion through the fusion section 3. The first pipe section 11 and the second pipe section 12 are each tubular. The pipe section 1 has a fiber-containing layer. The pipe section 1 having a fiber-containing layer includes a case in which the entire pipe section 1 is made of a fiber-containing layer and a case in which a part of the pipe section 1 is made of a fiber-containing layer. Since the fused portion 3 is formed by fusing the first tubular portion 11 and the second tubular portion 12, the fused portion 3 also has a fiber-containing layer. The longitudinal direction of the fibers contained in the fiber-containing layer in the tubular portion 1 is inclined with respect to the tube axis O1 of the tubular portion 1 in a plan view of the tubular portion 1. The first pipe portion 11 may not have a fiber-containing layer. When the first pipe portion 11 does not have a fiber-containing layer, the second pipe portion 12 has a fiber-containing layer. In addition, the second pipe portion 12 is preferably longer than the first pipe portion 11, and the fiber-containing layer of the long second pipe portion 12 can improve the pressure resistance and low stretchability of the piping member 10. The joint portion 2 is joined to the pipe portion 1. More specifically, the joint portion 2 is joined to one end portion of the pipe portion 1 (one end portion of the first pipe portion 11 (the end portion opposite to the fusion portion 3)).

[0012] An inner circumferential bead 4 is formed on the inner circumferential surface of the fusion portion 3 between the first pipe portion 11 and the second pipe portion 12. The first pipe portion 11 and the second pipe portion 12 each have an inner circumferential bead 4. The inner circumferential bead 4 has a first convex portion 4a on the first pipe portion 11 side and a second convex portion 4b on the second pipe portion 12 side. The first pipe portion 11 has the first convex portion 4a. The second pipe portion 12 has the second convex portion 4b. The inner circumferential bead 4 has an inner circumferential bead in the first convex portion 4a portion and an inner circumferential bead in the second convex portion 4b portion.

[0013] An outer peripheral bead 5 is formed on the outer peripheral surface of the fusion portion 3 between the first pipe portion 11 and the second pipe portion 12. The first pipe portion 11 and the second pipe portion 12 each have an outer peripheral bead 5. The outer peripheral bead 5 has a third convex portion 5a on the first pipe portion 11 side and a fourth convex portion 5b on the second pipe portion 12 side. The first pipe portion 11 has the third convex portion 5a. The second pipe portion 12 has the fourth convex portion 5b. The outer peripheral bead 5 has an inner peripheral bead in the third convex portion 5a portion and an inner peripheral bead in the fourth convex portion 5b portion.

[0014] In the first pipe portion 11 in a state where the first pipe portion 11 and the second pipe portion 12 are connected, a region where the inner peripheral bead 4 of the first pipe portion 11 is not formed is referred to as a region R1a. The region R1a is a region between X1a and X1b in FIG.

[0015] In the second pipe section 12 in a state where the first pipe section 11 and the second pipe section 12 are connected, a region where the inner peripheral bead 4 of the second pipe section 12 is not formed is referred to as region R2a. Region R2a is a region between X2a and X2b in FIG.

[0016] In the first pipe section 11 in a state where the first pipe section 11 and the second pipe section 12 are connected, the end section refers to a region from the end face of the first pipe section 11 to 3 cm inward in the direction in which the first pipe section 11 extends (region R1 in FIG. 1; region R1 is the region between X0 and X1a in FIG. 1). In the first pipe section 11 in a state where the first pipe section 11 and the second pipe section 12 are connected, region R1a refers to a region from the end face of the first pipe section 11 to 3 cm inward in the direction in which the first pipe section 11 extends (region R1 in FIG. 1) excluding a region where the inner circumferential bead 4 is formed (region R1b in FIG. 1; region R1b is the region between X0 and X1b in FIG. 1). However, when the bead width of the first convex portion 4a is 3 cm or more, in the first pipe portion 11 in a state in which the first pipe portion 11 and the second pipe portion 12 are connected, the end portion refers to a region from the end face of the first pipe portion 11 toward the inside in the extension direction of the first pipe portion 11 up to the bead width of the first convex portion 4a + 2.5 cm. Generally, the bead width of the first convex portion 4a is less than 2 cm.

[0017] In the second pipe section 12 in a state where the first pipe section 11 and the second pipe section 12 are connected, the end refers to a region from the end face of the second pipe section 12 to 3 cm inward in the direction in which the second pipe section 12 extends (region R2 in FIG. 1; region R2 is the region between X0 and X2a in FIG. 1). In the second pipe section 12 in a state where the first pipe section 11 and the second pipe section 12 are connected, region R2a refers to a region from the end face of the second pipe section 12 to 3 cm inward in the direction in which the second pipe section 12 extends (region R2 in FIG. 1) excluding a region where the inner circumferential bead 4 is formed (region R2b in FIG. 1; region R2b is the region between X0 and X1b in FIG. 1). However, when the bead width of the second convex portion 4b is 3 cm or more, in the second pipe portion 12 in a state in which the first pipe portion 11 and the second pipe portion 12 are connected, the end portion refers to a region from the end face of the second pipe portion 12 toward the inside in the extension direction of the second pipe portion 12 up to the bead width of the second convex portion 4b + 2.5 cm. Generally, the bead width of the second convex portion 4b is less than 2 cm.

[0018] In addition, in the first pipe section 11 before the first pipe section 11 and the second pipe section 12 are connected, the end section refers to the area extending from the end face of the first pipe section 11 to up to 3 cm inward in the extension direction of the first pipe section 11.

[0019] Furthermore, in the second pipe section 12 before the first pipe section 11 and the second pipe section 12 are connected, the end section refers to the area extending from the end face of the second pipe section 12 of the second resin pipe 2 to up to 3 cm inward in the extension direction of the second pipe section 12.

[0020] As shown in FIG. 2, in the fiber-containing layer of the tube portion 1, the longitudinal direction of the fiber 6 contained in the fiber-containing layer constituting the tube portion 1 is inclined with respect to the tube axis O1 direction of the tube portion 1 in a plan view of the tube portion 1. In other words, the longitudinal direction (orientation direction) of the fiber 6 moves away from the tube axis O1 as it approaches the tube axis O1 direction of the tube portion 1. More specifically, the orientation direction of the fiber 6 faces between the tube axis O1 direction and the direction perpendicular to the tube axis O1. As a result, as shown in FIG. 2, when the first tube portion 11 and the second tube portion 12 are fused, there is no significant difference between the longitudinal direction of the fiber 6 contained in the fiber-containing layer constituting the fused portion 3 and the longitudinal direction of the fiber 6 contained in the fiber-containing layer constituting the tube portion 1, so that the difference in strength between the first tube portion 11 and the second tube portion 12 and the fused portion 3 is reduced.

[0021] The angle θ at which the longitudinal direction of the fiber 6 is inclined with respect to the tube axis O1 direction is preferably such that, when the fiber-containing layer of the tube part 1 is observed in the XY cross section (a plane perpendicular to the Z direction, i.e., a cross section parallel to the tube axis), the YZ cross section (a plane perpendicular to the X direction, i.e., a cross section perpendicular to the tube axis), and the ZX cross section (a plane perpendicular to the Y direction, i.e., a cross section sliced ​​in the thickness direction of the fiber-containing layer), the average length of the fiber 6 is longer in the order of the ZX cross section>the YZ cross section>the XY cross section. If the fiber 6 is longer when viewed in the XY cross section than in the ZX cross section, this means that the fiber 6 is longer in the X direction (tube axis direction), and that the fiber 6 is oriented in the tube axis direction rather than the circumferential direction. If the fiber 6 is longer when viewed in the YZ cross section than in the ZX cross section, this means that the fiber 6 is longer in the Y direction (thickness direction), and that the fiber 6 is oriented in the thickness direction rather than the circumferential direction.

[0022] The fiber length of the fiber-containing layer is measured for the fiber-containing layer of the first tubular portion 11 and the second tubular portion 12 where no beads are formed, and is measured at the center portion in the thickness direction of the fiber-containing layer. In particular, for the ZX cross section, the fiber length is measured on a plane perpendicular to the plane passing through the tube axis O1, and at the center portion in the thickness direction of the fiber-containing layer. The measurement method involves photographing the cross section with a scanning electron microscope (e.g., JSM-6701F manufactured by JEOL Ltd.), analyzing the micrograph, and calculating the average fiber length. Examples of conditions for photographing with a scanning electron microscope include a deposition thickness of 10 nm, an acceleration voltage of 15 kV, and a magnification of 25 times.

[0023] Furthermore, when specifically measuring the angle θ at which the longitudinal direction of the fiber 6 is inclined with respect to the tube axis O1 direction, as shown in FIG. 3, the observation cross section α is limited to the ZX plane, the X-axis direction is set to 0°, the Z-axis direction is set to ±90°, and the angle at which the fiber faces the Z-axis with respect to the X-axis is calculated. At this time, fibers whose fiber length is less than twice the fiber diameter are fibers facing the Y-axis direction and are therefore excluded from the calculation. Next, the measured observation image is analyzed with image analysis software to recognize the fibers 6, and the angle and fiber length of the fibers facing the Z-axis with respect to the X-axis are measured, and the distribution of the number of each fiber is measured. The average value θ' of the total number of fibers 6 measured in this way is preferably 30° to 90°, and it is preferable that 40% or more of all fibers are included within ±25° of the average value θ'.

[0024] The first pipe 11 and the second pipe 12 may have a structure of only one fiber-containing layer (single layer), a structure of two layers (multilayer) in which a fiber-containing layer and a fiber-free layer that does not contain fibers are laminated, or a structure of three or more layers. The first pipe 11 and the second pipe 12 may be a single-layer pipe or a multi-layer pipe.

[0025] The combination of the first pipe portion 11 and the second pipe portion 12 may be a combination of a single-layer pipe and a single-layer pipe, a combination of a single-layer pipe and a multi-layer pipe, or a combination of a multi-layer pipe and a multi-layer pipe.

[0026] A specific example of the configuration of the first tube portion 11 and the second tube portion 12 will be described. As shown in FIG. 4, the entire tube portion 1 may be made up of a fiber-containing layer 30 . 5, the pipe section 1 may have an innermost layer 31 made of a polyolefin resin. That is, the pipe section 1 may have, in order from the flow path 20 side, the innermost layer 31 and the fiber-containing layer 30. By having the innermost layer 31 made of a polyolefin resin that does not contain fibers, the surface of the fiber-containing layer 30 is covered with the innermost layer 31 at the inner circumferential bead 4, so that the fibers contained in the fiber-containing layer 30 are less likely to flow out into the liquid flowing in the flow path 20. 6, the pipe section 1 may have an outermost layer 32 made of polyolefin resin. That is, the pipe section 1 may have, in order from the flow path 20 side, a fiber-containing layer 30 and an outermost layer 32. By having the outermost layer 32 made of polyolefin resin, when the pipe section 1 (first pipe section 11 in FIG. 1) and the joint section 2 are connected by heating, the connection is between resins, so that sufficient joint strength can be obtained. Furthermore, when the pipe section 1 (first pipe section 11) and the joint section 2 are connected by resins, the connection is between resins, so that sufficient joint strength can be obtained. 7, the pipe section 1 may have an innermost layer 31 made of a polyolefin resin and an outermost layer 32 made of a polyolefin resin. That is, the pipe section 1 may have, in this order from the flow path 20 side, the innermost layer 31, the fiber-containing layer 30, and the outermost layer 32. When the pipe section 1 has the innermost layer 31 made of a polyolefin resin, by also providing the outermost layer 32 made of a polyolefin resin, pressure is applied uniformly to the inside and outside of the pipe section 1 when the first pipe section 11 and the second pipe section 12 are fused, so that the inner circumferential bead 4 and the outer circumferential bead 5 can be formed uniformly.

[0027] The first pipe portion 11 and the second pipe portion 12 may have the same configuration or may have different configurations. If they have the same configuration, it is easy to form beads uniformly and easy to manufacture. When the first tubular portion 11 and the second tubular portion 12 have the same configuration, for example, the first tubular portion 11 and the second tubular portion 12 may be entirely composed of a fiber-containing layer as shown in Fig. 2. In this case, the fiber-containing layer of the first tubular portion 11 and the fiber-containing layer of the second tubular portion 12 are joined at the fusion portion 3. When the first pipe section 11 and the second pipe section 12 have the same configuration, for example, as shown in Fig. 8, the first pipe section 11 and the second pipe section 12 may have an innermost layer 31 and a fiber-containing layer 30. In this case, in the fusion section 3, the innermost layer 31 of the first pipe section 11 and the innermost layer 31 of the second pipe section 12 are connected to form an inner circumferential bead 4, and the fiber-containing layer 30 of the first pipe section 11 and the fiber-containing layer 30 of the second pipe section 12 are connected to form an outer circumferential bead 5. Since the first pipe portion 11 connected to the joint portion 2 has a fiber-containing layer, the fiber-containing layer can impart pressure resistance and low elasticity to the vicinity of the joint portion 2, making the piping member 10 have even better pressure resistance and low elasticity. When the first pipe section 11 and the second pipe section 12 have different configurations, for example, as shown in Fig. 9, the first pipe section 11 may be composed of a polyolefin resin layer 33, and the second pipe section 12 may have an innermost layer 31 and a fiber-containing layer 30. In this case, in the fusion section 3, the polyolefin resin layer 33 of the first pipe section 11 and the innermost layer 31 of the second pipe section 12 are connected to form an inner circumferential bead 4, and the polyolefin resin layer 33 of the first pipe section 11 and the fiber-containing layer 30 of the second pipe section 12 are connected to form an outer circumferential bead 5. The first pipe section 11 is composed only of a fiber-free layer, which facilitates joining of the joint section 2, which has a complex structure, to the first pipe section 11. For example, when the joint section 2 has a structure in which an incore is inserted into the first pipe section 11, the first pipe section 11 does not include a fiber-containing layer, which makes it easy to insert the incore of the joint section 2, and the first pipe section 11 can also be made into a piping member 10 that is flexibly easy to expand in diameter and difficult to break.

[0028] The first pipe portion 11 and the second pipe portion 12 contain a resin. The resin contained in the first pipe portion 11 and the resin contained in the second pipe portion 12 may be the same or different. Only one type of the above resin may be used, or two or more types may be used in combination.

[0029] Examples of the resin include polyolefin resin and vinyl chloride resin.

[0030] From the viewpoint of further improving pressure resistance, the resin is preferably a polyolefin resin or a vinyl chloride resin.

[0031] Examples of the polyolefin resin include polyethylene, polypropylene, polybutene, ethylene-vinyl acetate copolymer, and ethylene-α-olefin copolymer, etc. The polyolefin resin may be used alone or in combination of two or more kinds.

[0032] From the viewpoint of further improving pressure resistance, the polyolefin resin is preferably polyethylene or polypropylene, and more preferably polyethylene. The polyethylene may be crosslinked polyethylene.

[0033] The polyethylene may be a homopolymer of ethylene, a copolymer of a monomer containing ethylene, etc. Preferably, 50% by mass or more of the monomers constituting the polyethylene are ethylene, more preferably 80% by mass or more, and even more preferably 90% by mass or more. The polypropylene may be a homopolymer of propylene, a copolymer of a monomer containing propylene, etc. Preferably, 50% by mass or more of the monomers constituting the polypropylene is propylene, more preferably 80% by mass or more, and even more preferably 90% by mass or more.

[0034] The content of the resin is preferably 20% by mass or more and 80% by mass or less, and more preferably 30% by mass or more and 70% by mass or less, based on 100% by mass of the first tube portion 11 and the second tube portion 12. When the content of the resin is within the above range, the pressure resistance of the tube portion 1 can be further improved.

[0035] At least one of the first tubular portion 11 and the second tubular portion 12 has a fiber-containing layer. That is, only the first tubular portion 11 may have a fiber-containing layer, only the second tubular portion 12 may have a fiber-containing layer, or both the first tubular portion 11 and the second tubular portion 12 may have a fiber-containing layer. Only one type of the above fibers may be used, or two or more types may be used in combination.

[0036] The fibers may be inorganic or organic.

[0037] Examples of the inorganic fibers include glass fibers, carbon fibers, silicon-titanium-carbon composite fibers, boron fibers, and metal fibers.

[0038] Examples of the organic fibers include aramid fibers, vinylon fibers, polyester fibers, and polyamide fibers.

[0039] From the viewpoint of further increasing the pressure resistance, the fibers are preferably glass fibers.

[0040] The average fiber length of the fibers is preferably 100 μm or more and 1500 μm or less, more preferably 200 μm or more and 1000 μm or less, and even more preferably 300 μm or more and 800 μm or less. When the average fiber length of the fibers is within the above range, the pressure resistance of the tube portion 1 can be further improved.

[0041] The average fiber length is determined by measuring the fiber length of one fiber and averaging the fiber lengths of a plurality of fibers. The fiber length is the distance between one end and the other end of the fiber when the fiber is straightened.

[0042] The average fiber diameter of the fibers is preferably 5 μm or more and 17 μm or less, more preferably 7 μm or more and 14 μm or less, and even more preferably 9 μm or more and 14 μm or less. When the average fiber diameter of the fibers is within the above range, the pressure resistance of the tube portion 1 can be further improved.

[0043] The average fiber diameter is determined by determining the fiber diameter of one fiber and averaging the fiber diameters of a plurality of fibers.

[0044] The content of the above fibers is preferably 5% by mass or more and 30% by mass or less, and more preferably 10% by mass or more and 25% by mass or less, based on 100% by mass of the first tube portion 11 and the second tube portion 12. When the content of the above fibers is within the above range, the pressure resistance of the tube portion 1 can be further improved.

[0045] Each of the first tube portion 11 and the second tube portion 12 may contain other components such as a compatibilizer, a stabilizer, a stabilizing aid, a lubricant, a processing aid, an impact modifier, a heat resistance improver, an antioxidant, an ultraviolet absorber, a light stabilizer, a filler, a pigment, a plasticizer, etc. Each of the above other components may be used alone or in combination of two or more kinds.

[0046] Examples of the compatibilizer include maleic acid modified polyolefin, silane modified polyolefin, chlorinated polyolefin, etc. These compatibilizers are not included in the polyolefin resin. The compatibilizer may be used alone or in combination of two or more.

[0047] Examples of the stabilizer include a heat stabilizer and a heat stabilization assistant. Examples of the heat stabilizer include an organic tin stabilizer, a lead stabilizer, a calcium-zinc stabilizer, a barium-zinc stabilizer, and a barium-cadmium stabilizer. Examples of the organic tin stabilizer include dibutyltin mercapto, dioctyltin mercapto, dimethyltin mercapto, dibutyltin mercapto, dibutyltin maleate, dibutyltin maleate polymer, dioctyltin maleate, dioctyltin maleate polymer, dibutyltin laurate, and dibutyltin laurate polymer. The stabilizer may be used alone or in combination of two or more.

[0048] Examples of the heat stabilization assistant include epoxidized soybean oil, phosphoric acid ester, polyol, hydrotalcite, zeolite, etc. The heat stabilization assistant may be used alone or in combination of two or more kinds.

[0049] The lubricant includes internal lubricants, external lubricants, etc. The internal lubricant is used to reduce the flow viscosity of the molten resin during molding and to prevent frictional heat generation. The internal lubricant includes butyl stearate, lauryl alcohol, stearyl alcohol, epoxy soybean oil, glycerin monostearate, stearic acid, bisamide, etc. The external lubricant is used to increase the sliding effect between the molten resin and the metal surface during molding. Examples of the external lubricant include paraffin wax, polyolefin wax, ester wax, montanic acid wax, etc. The lubricant may be used alone or in combination of two or more kinds.

[0050] Examples of the processing aid include acrylic processing aids. Examples of the acrylic processing aid include alkyl acrylate-alkyl methacrylate copolymers having a weight average molecular weight of 100,000 to 2,000,000. Specific examples of the acrylic processing aid include n-butyl acrylate-methyl methacrylate copolymers, 2-ethylhexyl acrylate-methyl methacrylate-butyl methacrylate copolymers, etc. The processing aids may be used alone or in combination of two or more.

[0051] Examples of the impact modifier include methyl methacrylate-butadiene-styrene copolymer (MBS), acrylic rubber, etc. The impact modifier may be used alone or in combination of two or more kinds.

[0052] The antioxidant may be a phenol-based antioxidant, etc. The antioxidant may be used alone or in combination of two or more kinds.

[0053] Examples of the ultraviolet absorbent include a salicylic acid ester ultraviolet absorbent, a benzophenone ultraviolet absorbent, a benzotriazole ultraviolet absorbent, a cyanoacrylate ultraviolet absorbent, etc. The ultraviolet absorbent may be used alone or in combination of two or more kinds.

[0054] The light stabilizer may be a hindered amine light stabilizer, etc. The light stabilizer may be used alone or in combination of two or more kinds.

[0055] Examples of the filler include calcium carbonate, talc, etc. The filler may be used alone or in combination of two or more kinds.

[0056] Examples of the pigment include organic pigments and inorganic pigments. Examples of the organic pigment include azo-based organic pigments, phthalocyanine-based organic pigments, threne-based organic pigments, dye lake-based organic pigments, etc. Examples of the inorganic pigment include oxide-based inorganic pigments, molybdenum chromate-based inorganic pigments, sulfide-selenide-based inorganic pigments, ferrocyanide-based inorganic pigments, etc. The pigments may be used alone or in combination of two or more.

[0057] The plasticizer may be added for the purpose of improving the processability during molding. Since the addition of a plasticizer may reduce the heat resistance of the resin pipe, it is preferable to add a small amount of plasticizer. Examples of the plasticizer include dibutyl phthalate, di-2-ethylhexyl phthalate, di-2-ethylhexyl adipate, etc. The plasticizer may be used alone or in combination of two or more kinds.

[0058] The joint part 2 is a mechanical joint that connects pipes with a coupler without welding or gas pressure welding. One end part 2A of the joint part 2 is joined to one end part of the pipe part 1 (one end part of the first pipe part 11 (the end part opposite to the fused part 3)). More specifically, one end part 2A of the joint part 2 is fitted onto one end part of the first pipe part 11. Meanwhile, the other end part 2B of the joint part 2 is open, and has a socket 2C for inserting and connecting another pipe.

[0059] The joint portion 2 may be integrally formed with the first pipe portion 11 by injection molding.

[0060] The joint part 2 may have a one-layer structure, a two-layer structure, or a three-layer structure or more. When the joint part 2 is integrally molded with the first pipe part 11, the joint part 2 and the first pipe part have the same structure. For example, when the joint part 2 has a one-layer structure, the first pipe part 11 integrally molded also has a one-layer structure.

[0061] The joint portion 2 contains the same resin as the first pipe portion 11 and the second pipe portion 12. The resin contained in the joint portion 2 may be the same as or different from the resin contained in the first pipe portion 11 and the resin contained in the second pipe portion 12. Only one type of the above resin may be used, or two or more types may be used in combination.

[0062] The joint part 2 may have a fiber-containing layer, similar to the first pipe part 11 and the second pipe part 12. Only one type of the above-mentioned fiber may be used, or two or more types may be used in combination. Examples of the above-mentioned fiber include the same ones as those used in the first pipe part 11 and the second pipe part 12.

[0063] When the joint part 2 has a fiber-containing layer, the longitudinal direction of the fibers contained in the fiber-containing layer is not particularly limited, but is preferably inclined toward the pipe axis O1 of the pipe part 1.

[0064] According to the piping member 10 of this embodiment, the longitudinal direction of the fibers 6 contained in the fiber-containing layer constituting the pipe portion 1 is inclined with respect to the pipe axis O1 direction of the pipe portion 1 in a plan view of the pipe portion 1, so that when the first pipe portion 11 and the second pipe portion 12 are fused together, there is no significant difference between the longitudinal direction of the fibers 6 contained in the fiber-containing layer constituting the fused portion 3 and the longitudinal direction of the fibers 6 contained in the fiber-containing layer constituting the pipe portion 1. As a result, the difference in strength between the first pipe portion 11 and the second pipe portion 12 and the fused portion 3 is reduced.

[0065] [Manufacturing method for piping components] Hereinafter, a method for manufacturing a piping member according to an embodiment of the present invention will be described with reference to the drawings.

[0066] 10 to 12 are cross-sectional views showing a method for manufacturing a piping member according to an embodiment of the present invention.

[0067] The first pipe portion 11 and the second pipe portion 12 constituting the pipe portion 1 are molded by extrusion molding or the like. When the first tube portion 11 and the second tube portion 12 have a single-layer structure, any method capable of flowing the resin composition containing the resin and the fiber in a direction corresponding to the circumferential direction of the molded tube can be used without any particular limitation. When the first tube portion 11 and the second tube portion 12 have a two-layer structure (innermost layer 31 / fiber-containing layer 30, fiber-containing layer 30 / outermost layer 32), a first resin composition containing the resin and the fiber and forming the fiber-containing layer 30, and a second resin composition containing the resin and forming the innermost layer 31 or the outermost layer 32 are prepared, and any method capable of flowing the first resin composition and the second resin composition in a direction corresponding to the circumferential direction of the molded tube can be used without any particular limitation. Furthermore, when the first tube section 11 and the second tube section 12 have a three-layer structure (innermost layer 31 / fiber-containing layer 30 / outermost layer 32), any method can be used that is capable of preparing a first resin composition containing the above resin and the above fiber and forming the fiber-containing layer 30, a second resin composition containing the above resin and forming the innermost layer 31, and a third resin composition containing the above resin and forming the outermost layer 32, and causing the first resin composition, second resin composition, and third resin composition to flow in a direction corresponding to the circumferential direction of the molded tube, without any particular limitation.

[0068] The first pipe portion 11 and the second pipe portion 12 obtained as described above are fused (connected). FIG. 10 is a cross-sectional view that shows a schematic diagram of the first tube portion 11 and the second tube portion 12 before fusion (connection). Using the first tube section 11 and the second tube section 12 shown in Figure 10, the end of the first tube section 11 and the end of the second tube section 12 are connected by fusing them together via the state shown in Figures 11 and 12 to obtain the tube section 1.

[0069] The fusion method is not particularly limited, and a conventionally known method can be used. The fusion preferably includes a heating step of heating the end of the first tube portion 11 before connection and the end of the second tube portion 12 before connection, and a crimping step of crimping the heated end of the first tube portion 11 and the heated end of the second tube portion 12. In the heating step, it is preferable to heat the end face of the first tube portion 11 before connection, and it is preferable to heat the end face of the second tube portion 12 before connection. In the above-mentioned crimping step, it is preferable to crimp the end face of the heated first tube portion 11 and the end face of the heated second tube portion 12 together.

[0070] FIG. 11 is a cross-sectional view for explaining the heating step in fusion bonding.

[0071] In the heating step, it is preferable to heat the end of the first tube portion 11 and the end of the second tube portion 12 using the heater H. When heating with the heater H, it is preferable to heat from the end face side of the first tube portion 11 and the end face side of the second tube portion 12.

[0072] The heating temperature in the heating step can be appropriately changed depending on the types of blended components such as resin contained in the first tube portion 11 and the second tube portion 12. The heating temperature is preferably 230°C or higher and 250°C or lower, and more preferably 235°C or higher and 245°C or lower.

[0073] The heating time in the heating step can be appropriately changed depending on the types of blended components such as resin contained in the first tubular portion 11 and the second tubular portion 12, and the diameters of the first tubular portion 11 and the second tubular portion 12.

[0074] FIG. 12 is a cross-sectional view for explaining the pressure bonding step in fusion bonding.

[0075] The pressure in the crimping step can be appropriately changed depending on the types of blended components such as resin contained in the first tube portion 11 and the second tube portion 12. The pressure is preferably 1 MPa or more and 3 MPa or less, and more preferably 1.2 MPa or more and 2.8 MPa or less.

[0076] The crimping time in the crimping step can be changed appropriately depending on the types of compounding ingredients such as resin contained in the first tube portion 11 and the second tube portion 12, and the diameters of the first tube portion 11 and the second tube portion 12.

[0077] As described above, the first tube portion 11 and the second tube portion 12 are connected by fusion to form a fused portion 3, and a tube portion 1 in which the first tube portion 11 and the second tube portion 12 are connected via the fused portion 3 can be obtained, as shown in Figure 1.

[0078] A joint portion 2 is joined to one end portion of the pipe portion 1 obtained as described above (one end portion of the first pipe portion 11 (the end portion opposite to the fused portion 3)) to obtain the piping member 10 shown in FIG. 1.

[0079] <Other embodiments> It should be noted that the present invention is not limited to the above-described embodiment.

[0080] For example, a piping member 100 according to a modified example as shown in Fig. 13 may be employed. In the piping member 100 according to the modified example, the same components as those in the above embodiment are denoted by the same reference numerals, and the description thereof will be omitted, and only the differences will be described.

[0081] A piping member 100 according to a modified example shown in FIG. 13 has a joint portion 110 having a different structure from the piping member 10 described above. The joint part 110 is a mechanical joint. One end 110A of the joint part 110 is connected to one end of the pipe part 1 (one end of the first pipe part 11 (the end opposite to the fused part 3)). More specifically, one end 110A of the joint part 110 is inserted into one end of the first pipe part 11. Furthermore, a pressing ring 120 is fitted onto the outer periphery of one end of the first pipe part 11 to which the one end 110A of the joint part 110 is connected. Meanwhile, the other end 110B of the joint part 110 is open, and has a socket 110C for inserting and connecting another pipe.

[0082] Although the embodiment of the present invention has been described in detail above with reference to the drawings, the embodiment is merely an example of the present invention. Therefore, the present invention is not limited to the configuration of the embodiment, and it goes without saying that even if there are design changes within the scope of the present invention, they are included in the present invention. In addition, for example, when multiple configurations are included in each embodiment, it goes without saying that possible combinations of these configurations are included even if not specifically stated. In addition, when multiple examples or modified examples are disclosed as the present invention, it goes without saying that possible combinations of configurations across these are included even if not specifically stated. In addition, it goes without saying that the configurations depicted in the drawings are included even if not specifically stated. Furthermore, when the term "etc." is used, it is used to mean that equivalents are included. EXAMPLES

[0083] The present invention will be described in more detail below with reference to examples and comparative examples, but the present invention is not limited to the following examples.

[0084] [Example 1] As a resin composition for manufacturing the piping that would become the first pipe section and the second pipe section, a resin composition (A-1) containing 70 mass% high-density polyethylene (equivalent to PE100) and 30 mass% glass fiber (chopped strand shape, average fiber length: 500 μm, average fiber diameter: 13 μm, olefin converging agent, silane surface treatment product) was prepared. This resin composition was extrusion molded, and the rotary take-off machine was set to rotate at 74° with respect to the axis, and the extruded tubular body was taken up and twisted in the circumferential direction. It was then cooled and solidified in a first water tank and a second water tank to obtain a single-layer pipe. In this way, a single-layer pipe having only a fiber-containing layer was manufactured. A cross section of the obtained single-layer pipe cut perpendicular to the axis was observed using a scanning electron microscope (product name: JSM-671F, manufactured by JEOL Ltd.) under conditions of a deposition thickness of 10 nm, an acceleration voltage of 15 kV, and a magnification of 25 times, and it was confirmed that the glass fibers were oriented in the circumferential direction of the single-layer pipe. In addition, since the obtained single-layer pipe had only the fiber-containing layer, the thickness of the fiber-containing layer was 100% of the total thickness of the single-layer pipe. Two single-layer pipes were prepared, one of which was designated as a first pipe section and the other as a second pipe section. The end of the first tube part and the end of the second tube part were heated at 235°C for 35 seconds from the end face of the first tube part and the end face of the second tube part using a heater (product name: DELTA160V1, manufactured by Ritmo Co., Ltd.). After heating, the heater was removed, and the first tube part and the second tube part were crimped at a pressure of 1.5 MPa for 2 minutes. In this way, the fused tube (tube part) of Example 1 in which the first tube part and the second tube part were connected by butt fusion was produced.

[0085] [Example 2] A resin composition (A-2) containing 75% by mass of high density polyethylene (equivalent to PE100) and 25% by mass of glass fiber (chopped strand shape, average fiber length: 500 μm, average fiber diameter: 13 μm, olefin binder, silane surface treatment product) was prepared as a resin composition for producing a fiber-containing layer of the piping that will become the first and second pipes. In addition, a resin composition (B-2) containing high density polyethylene (equivalent to PE100) was prepared as a resin composition for producing the outermost layer of the piping that will become the first and second pipes. Using these resin compositions (A-2) and (B-2), a two-layer pipe having a fiber-containing layer and an outermost layer was produced in the same manner as in Example 1. A cross section of the obtained two-layer pipe cut along a plane perpendicular to the axis was observed in the same manner as in Example 1, and it was confirmed that the glass fibers were oriented in the circumferential direction. The thickness of the fiber-containing layer was 80% of the total thickness of the obtained two-layered pipe. The total thickness and the fiber layer thickness of the two-layered pipe were measured by visually observing the cross section and using a vernier caliper. Two double-layer pipes were prepared, one of which was designated as the first pipe section and the other as the second pipe section. The ends of the first tube portion and the second tube portion were crimped in the same manner as in Example 1 to produce a fused tube (tube portion) of Example 2 in which the first tube portion and the second tube portion were connected by butt fusion.

[0086] [Example 3] A resin composition (A-3) containing 79% by mass of high density polyethylene (equivalent to PE100) and 21% by mass of glass fiber (chopped strand shape, average fiber length: 500 μm, average fiber diameter: 13 μm, olefin binder, silane surface treatment product) was prepared as a resin composition for producing a fiber-containing layer of the piping that will become the first and second pipes. In addition, a resin composition (B-3) containing high density polyethylene (equivalent to PE100) was prepared as a resin composition for producing the outermost layer of the piping that will become the first and second pipes. In addition, a resin composition (C-3) containing high density polyethylene (equivalent to PE100) was prepared as a resin composition for producing the innermost layer of the piping that will become the first and second pipes. Using these resin compositions (A-3), (B-3) and (C-3), three-layer pipes having an innermost layer, a fiber-containing layer and an outermost layer were manufactured in the same manner as in Example 1. A cross section of the obtained three-layer pipe cut along a plane perpendicular to the axis was observed in the same manner as in Example 1, and it was confirmed that the glass fibers were oriented in the circumferential direction. The thickness of the fiber-containing layer relative to the total thickness of the obtained three-layered pipe was 67%. The total thickness and the fiber layer thickness of the three-layered pipe were measured in the same manner as in Example 2. Two three-layer pipes were prepared, one of which was designated as the first pipe section and the other as the second pipe section. The ends of the first tube portion and the second tube portion were crimped in the same manner as in Example 1 to produce a fused tube (tube portion) of Example 3 in which the first tube portion and the second tube portion were connected by butt fusion.

[0087] [Example 4] A resin composition (A-4) containing 89% by mass of high density polyethylene (equivalent to PE100) and 11% by mass of glass fiber (chopped strand shape, average fiber length: 500 μm, average fiber diameter: 13 μm, olefin binder, silane surface treatment product) was prepared as a resin composition for producing a fiber-containing layer of the piping that will become the first piping section. In addition, a resin composition (B-4) containing high density polyethylene (equivalent to PE100) was prepared as a resin composition for producing the outermost layer of the piping that will become the first piping section. Furthermore, a resin composition (C-4) containing high density polyethylene (equivalent to PE100) was prepared as a resin composition for producing the innermost layer of the piping that will become the first piping section. These resin compositions (A-4), (B-4) and (C-4) were extrusion molded using a die in which the flow path in the middle of the die was tournament-branched (specifically, 8-branched) from upstream to downstream in the same manner as in Example 1. In this way, a three-layer pipe having an innermost layer, a fiber-containing layer and an outermost layer was manufactured. A cross section of the obtained three-layer pipe cut along a plane perpendicular to the axis was observed in the same manner as in Example 1, and it was confirmed that the glass fibers were oriented in the circumferential direction. The thickness of the fiber-containing layer was 50% of the total thickness of the obtained three-layered pipe. The total thickness and the fiber layer thickness of the three-layered pipe were measured in the same manner as in Example 2. The obtained three-layer pipe was used as the first pipe section, and a pipe having the same inner and outer diameters as the three-layer pipe and made only of high-density polyethylene (equivalent to PE100) was used as the second pipe section. The ends of the first tube portion and the second tube portion were crimped in the same manner as in Example 1 to produce a fused tube (tube portion) of Example 4 in which the first tube portion and the second tube portion were connected by butt fusion.

[0088] [Example 5] A resin composition (A-5) containing 84% by mass of polypropylene and 16% by mass of glass fiber (chopped strand shape, average fiber length: 500 μm, average fiber diameter: 13 μm, olefin binder, silane surface treatment product) was prepared as a resin composition for producing a fiber-containing layer of the piping that will become the first and second pipes. In addition, a resin composition (B-5) containing high-density polyethylene (equivalent to PE100) was prepared as a resin composition for producing the outermost layer of the piping that will become the first and second pipes. These resin compositions (A-5) and (B-5) were extrusion molded using a die in which the flow path in the middle of the die was tournament-branched (specifically, 8-branched) from upstream to downstream, thereby producing a two-layer pipe having a fiber-containing layer and an outermost layer. A cross section of the obtained two-layer pipe cut along a plane perpendicular to the axis was observed in the same manner as in Example 1, and it was confirmed that the glass fibers were oriented in the circumferential direction. The thickness of the fiber-containing layer was 80% of the total thickness of the obtained two-layer pipe. The total thickness and the fiber layer thickness of the two-layer pipe were measured in the same manner as in Example 2. Two double-layer pipes were prepared, one of which was designated as the first pipe section and the other as the second pipe section. The ends of the first tube portion and the second tube portion were crimped in the same manner as in Example 1 to produce a fused tube (tube portion) of Example 5 in which the first tube portion and the second tube portion were connected by butt fusion.

[0089] [Example 6] A resin composition (A-6) containing 89% by mass of high density polyethylene (equivalent to PE100) and 11% by mass of glass fiber (chopped strand shape, average fiber length: 500 μm, average fiber diameter: 13 μm, olefin binder, silane surface treatment product) was prepared as a resin composition for producing a fiber-containing layer of the piping that will become the first and second pipes. In addition, a resin composition (B-6) containing high density polyethylene (equivalent to PE100) was prepared as a resin composition for producing the outermost layer of the piping that will become the first and second pipes. These resin compositions (A-6) and (B-6) were extrusion molded using a die in which the flow path in the middle of the die was tournament-branched (specifically, 8-branched) from upstream to downstream, thereby producing a two-layer pipe having a fiber-containing layer and an outermost layer in the same manner as in Example 1. A cross section of the obtained two-layer pipe cut along a plane perpendicular to the axis was observed in the same manner as in Example 1, and it was confirmed that the glass fibers were oriented in the circumferential direction. The thickness of the fiber-containing layer was 30% of the total thickness of the obtained two-layered pipe. The total thickness and the fiber layer thickness of the two-layered pipe were measured in the same manner as in Example 2. Two double-layer pipes were prepared, one of which was designated as the first pipe section and the other as the second pipe section. The ends of the first tube portion and the second tube portion were crimped in the same manner as in Example 1 to produce a fused tube (tube portion) of Example 6 in which the first tube portion and the second tube portion were connected by butt fusion.

[0090] [Example 7] A resin composition (A-7) containing 93% by mass of high density polyethylene (equivalent to PE100) and 21% by mass of glass fiber (chopped strand shape, average fiber length: 500 μm, average fiber diameter: 13 μm, olefin binder, silane surface treatment product) was prepared as a resin composition for producing a fiber-containing layer of the piping that will become the first and second pipes. In addition, a resin composition (B-7) containing high density polyethylene (equivalent to PE100) was prepared as a resin composition for producing the outermost layer of the piping that will become the first and second pipes. In addition, a resin composition (C-7) containing high density polyethylene (equivalent to PE100) was prepared as a resin composition for producing the innermost layer of the piping that will become the first and second pipes. Using these resin compositions (A-7), (B-7) and (C-7), three-layer pipes having an innermost layer, a fiber-containing layer and an outermost layer were manufactured in the same manner as in Example 1. A cross section of the obtained three-layer pipe cut along a plane perpendicular to the axis was observed in the same manner as in Example 1, and it was confirmed that the glass fibers were oriented in the circumferential direction. The thickness of the fiber-containing layer was 50% of the total thickness of the obtained three-layered pipe. The total thickness and the fiber layer thickness of the three-layered pipe were measured in the same manner as in Example 2. Two three-layer pipes were prepared, one of which was designated as the first pipe section and the other as the second pipe section. The ends of the first tube portion and the second tube portion were crimped in the same manner as in Example 1 to produce a fused tube (tube portion) of Example 7 in which the first tube portion and the second tube portion were connected by butt fusion.

[0091] [Comparative Example 1] The resin composition (A-2) and the resin composition (B-2) prepared in Example 2 were used for extrusion molding, and the tubular body was taken up without rotating the rotary take-up machine to produce a two-layer pipe having a fiber-containing layer and an outermost layer. A cross section of the obtained two-layered pipe cut perpendicular to the axis was observed in the same manner as in Example 1, and it was confirmed that the glass fibers were oriented in the axial direction of the two-layered pipe. The thickness of the fiber-containing layer was 80% of the total thickness of the obtained two-layer pipe. The total thickness and the fiber layer thickness of the two-layer pipe were measured in the same manner as in Example 2. Two double-layer pipes were prepared, one of which was designated as the first pipe section and the other as the second pipe section. The ends of the first tube portion and the second tube portion were crimped in the same manner as in Example 1 to produce a fused tube (tube portion) of Comparative Example 1 in which the first tube portion and the second tube portion were connected by butt fusion.

[0092] [Comparative Example 2] The resin composition (A-3), the resin composition (B-3), and the resin composition (C-3) prepared in Example 3 were extrusion molded, and the tubular body was taken up without rotating the rotary take-up machine, to produce a three-layer pipe having an innermost layer, a fiber-containing layer, and an outermost layer. A cross section of the obtained three-layered pipe cut perpendicular to the axis was observed in the same manner as in Example 1, and it was confirmed that the glass fibers were oriented in the axial direction of the three-layered pipe. The thickness of the fiber-containing layer relative to the total thickness of the obtained three-layered pipe was 67%. The total thickness and the fiber layer thickness of the three-layered pipe were measured in the same manner as in Example 2. Two three-layer pipes were prepared, one of which was designated as the first pipe section and the other as the second pipe section. The ends of the first tube portion and the second tube portion were crimped in the same manner as in Example 1 to produce a fused tube (tube portion) of Comparative Example 2 in which the first tube portion and the second tube portion were connected by butt fusion.

[0093] [Comparative Example 3] A resin composition containing 60 mass% high-density polyethylene (equivalent to PE100) and 40 mass% glass fiber (chopped strand shape, average fiber length: 500 μm, average fiber diameter: 13 μm, olefin binder, silane surface treatment) was prepared as a resin composition for manufacturing the piping that would become the first pipe section and the second pipe section. Using this resin composition, a single-layer pipe was produced in the same manner as in Example 1. The obtained single-layer pipe had a poor appearance and could not be subjected to the following evaluation.

[0094] The fusion strength of the fusion tubes obtained in Examples 1 to 7 and Comparative Examples 1 and 2 was evaluated by the following method.

[0095] [evaluation] (1) Fusion strength The fusion strength of the fusion portion formed between the first tube portion and the second tube portion was measured by the following method. In accordance with JIS K 6815-1 and JIS K 6815-3, a dumbbell-shaped sample was taken from the pipe portion 1 so that the bead portion was located in the center, and a tensile test was performed on the sample using a tensile tester under tensile conditions of 25 mm / min and 23°C to measure the tensile yield stress and confirm the fracture location. The criteria for judging the fusion strength were as follows: ◎: Tensile yield stress is 30 MPa or more and the fracture location is other than the bead area ○: Tensile yield stress is 20 MPa or more and the fracture location is other than the bead part ×: Tensile yield stress is less than 20 MPa, or the fracture occurs in the bead area.

[0096] [Table 1]

[0097] The results in Table 1 show that the fusion tubes of Examples 1 to 7 have excellent fusion strength. [Explanation of symbols]

[0098] 1 Pipe section 2,110 Joint 3 Fusion part 4 Inner bead 5 Periphery bead 10,100 Piping materials 11 First tube section 12 Second Tube 20 Flow Path 30 Fiber-containing layer 31 Innermost layer 32 Outermost layer 120 Retaining ring

Claims

1. A piping component comprising: a resin pipe section having a fiber-containing layer formed of a resin composition containing a resin and a fiber; and a mechanical joint section joined to the pipe section (excluding a piping component having an electric fusion joint in which a coil that generates heat when an electric current is passed through it is embedded), The tube portion includes a first tube portion, a second tube portion, and a fusion portion formed between the first tube portion and the second tube portion, The fused portion is formed with an outer peripheral bead that is constituted by the fiber-containing layer and protrudes from the outer surface of the pipe portion, A piping member, wherein a longitudinal direction of the fibers contained in the fiber-containing layer in the tubular portion is inclined with respect to a tubular axis direction of the tubular portion in a plan view of the tubular portion.

2. The piping member according to claim 1 , wherein the pipe portion has an innermost layer made of a polyolefin resin.

3. The piping member according to claim 1 , wherein the pipe portion has an outermost layer made of a polyolefin resin.

4. The piping member according to claim 1 , wherein the pipe portion has an innermost layer made of a polyolefin resin and an outermost layer made of a polyolefin resin.

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