Hydrogen transport pipe having excellent high-pressure resistance and flexibility characteristics

Abstract

The present invention relates to a hydrogen transport pipe having excellent high-pressure resistance and flexibility characteristics. Particularly, the present invention relates to a hydrogen transport pipe which is not only excellent in high-pressure resistance characteristics that prevent expansion or deformation caused by the high pressure of hydrogen being transported, but also satisfies excellent flexibility characteristics required for long-distance hydrogen transport, and which enables cost reduction for installation.

Description

Hydrogen transport piping with excellent high pressure resistance and bending characteristics

[0001] The present invention relates to a hydrogen transport pipe with excellent high pressure resistance and bending characteristics. Specifically, the present invention relates to a hydrogen transport pipe that not only has excellent high pressure resistance characteristics in which it does not expand or deform under the high pressure of the transported hydrogen, but also satisfies the excellent bending characteristics required for long-distance hydrogen transport and can reduce installation costs.

[0002] Recently, due to eco-friendly issues, there is an increasing demand for the use of hydrogen energy instead of petroleum energy. Consequently, hydrogen refueling stations and storage facilities are being installed in remote areas or within cities to facilitate the convenient utilization of this hydrogen, and methods for transporting hydrogen to these locations are being required.

[0003] Conventionally, most of the long-distance transport of hydrogen has relied on trailers, making it difficult to stably supply large quantities of hydrogen. In some cases, metal hydrogen transport pipelines are used based at hydrogen production bases, but the installation difficulty is very high, and due to the characteristics of metal pipelines, they cannot be wound onto bobbins, so only short straight pipelines of less than 10 meters can be transported, resulting in high installation costs as connections must be made every 10 meters at the site.

[0004] Meanwhile, although carbon steel is generally used as a metal piping material for transporting city gas and the like, hydrogen embrittlement may occur during hydrogen transport; that is, as hydrogen molecules penetrate into the metal structure and gradually diffuse, the ductility or tensile strength of the metal may decrease.

[0005] In addition, stainless steel can be considered as a material with excellent hydrogen permeability barrier properties to avoid or minimize hydrogen embrittlement in hydrogen transport piping, but this presents the problem of increased piping material costs. Furthermore, although piping made of materials such as polymers or aluminum is being developed, it does not satisfy all the required characteristics for long-distance hydrogen transport, such as pressure resistance at the 40 bar level, hydrogen permeability barrier properties at the level of stainless steel, and a minimum bending radius for winding onto a bobbin.

[0006] Therefore, there is an urgent need for hydrogen transport piping that not only possesses excellent high-pressure resistance characteristics without expanding or deforming under the high pressure of the transported hydrogen, but also satisfies the excellent bending characteristics required for long-distance hydrogen transport and can reduce installation costs.

[0007] The present invention aims to provide a hydrogen transport pipe that not only has excellent high-pressure resistance characteristics in which it does not expand or deform under the high pressure of the transported hydrogen, but also satisfies the excellent bending characteristics required for long-distance hydrogen transport and can reduce installation costs.

[0008] To solve the above problem, the present invention,

[0009] A hydrogen transport pipe is provided, comprising: a tube-shaped liner having a hydrogen transport channel formed inside; and a reinforcing layer formed on the outside of the liner, wherein the reinforcing layer is formed by the transverse winding of a fiber-reinforced polymer tape in which a plurality of reinforcing fiber yarns are arranged within a tape-shaped polymer resin, wherein each of the plurality of reinforcing fiber yarns is formed by twisting and combining a plurality of reinforcing fibers, and the void area ratio, which is the ratio of the area of ​​the empty space not filled with the polymer resin based on the total cross-sectional area of ​​the space between adjacent reinforcing fibers bordered by a virtual circle that contacts the reinforcing fibers arranged at the outermost among the plurality of reinforcing fibers constituting each of the reinforcing fiber yarns in any cross-section, is 50% or more.

[0010] Herein, a hydrogen transport pipe is provided, characterized in that the area ratio of the above voids is 50 to 80%.

[0011] In addition, the present invention provides a hydrogen transport pipe characterized in that the ovality of each of the plurality of reinforcing fiber yarns, specifically the short diameter to long diameter, is 0.5 or greater.

[0012] Meanwhile, the reinforcing layer comprises at least one lower reinforcing layer and at least one upper reinforcing layer formed outside the lower reinforcing layer, wherein the lower reinforcing layer is formed by the transverse winding of a fiber-reinforced polymer tape in which a plurality of reinforcing fibers are arranged within a tape-shaped polymer resin, and the plurality of reinforcing fibers are extended along the longitudinal direction of the tape and spread out and arranged in the width direction of the tape, and the upper reinforcing layer is formed by the transverse winding of a fiber-reinforced polymer tape in which a plurality of reinforcing fiber yarns are arranged within a tape-shaped polymer resin, and the plurality of reinforcing fiber yarns are extended along the longitudinal direction of the tape and arranged at intervals from each other in the width direction of the tape, thereby providing a hydrogen transport pipe.

[0013] Herein, the average spacing between a plurality of reinforcing fibers of the fiber-reinforced polymer tape forming the lower reinforcing layer is shorter than the average spacing between a plurality of reinforcing fiber yarns of the fiber-reinforced polymer tape forming the upper reinforcing layer, the average spacing between the plurality of reinforcing fibers is the average value of the horizontal distances between adjacent reinforcing fibers, and the average spacing between the plurality of reinforcing fiber yarns is the average value of the horizontal distances between adjacent reinforcing fiber yarns, thereby providing a hydrogen transport pipe.

[0014] In addition, the present invention provides a hydrogen transport pipe characterized in that the thickness of the fiber-reinforced polymer tape forming the lower reinforcing layer is smaller than the thickness of the fiber-reinforced polymer tape forming the upper reinforcing layer.

[0015] In addition, the plurality of reinforcing fibers in the fiber-reinforced polymer tape forming the lower reinforcing layer may include one or more reinforcing fiber bundles formed by combining two or more reinforcing fibers, and the height of each of the reinforcing fibers or reinforcing fiber bundles is 0.3 mm or less, thereby providing a hydrogen transport pipe.

[0016] Herein, a hydrogen transport pipe is provided, characterized in that the height of each of the plurality of reinforcing fiber yarns in the fiber-reinforced polymer tape forming the upper reinforcing layer is 0.5 mm or more.

[0017] Furthermore, the above upper reinforcing layer comprises a first upper reinforcing layer formed on the outside of the lower reinforcing layer and a second upper reinforcing layer formed on the outside of the first upper reinforcing layer, and is characterized in that the transverse winding direction of the fiber-reinforced polymer tape forming each of the first upper reinforcing layer and the second upper reinforcing layer is different, thereby providing a hydrogen transport pipe.

[0018] Meanwhile, the lower reinforcing layer comprises a first lower reinforcing layer formed on the outside of the liner and a second lower reinforcing layer formed on the outside of the first lower reinforcing layer, and the transverse winding direction of the fiber-reinforced polymer tape forming each of the first lower reinforcing layer and the second lower reinforcing layer is different, thereby providing a hydrogen transport pipe.

[0019] In addition, a hydrogen transport pipe is provided, characterized in that, based on the total weight of the fiber-reinforced polymer tape, the total weight of the reinforcing fiber and the reinforcing fiber yarn is 30 to 90 weight percent.

[0020] In addition, the above-mentioned reinforcing fiber yarn is characterized by having a tex of 440 to 16,000, thereby providing a hydrogen transport pipe.

[0021] Furthermore, a hydrogen transport pipe is provided, characterized in that the transverse angle of the lower reinforcing layer is greater than the transverse angle of the upper reinforcing layer.

[0022] Meanwhile, the present invention provides a hydrogen transport pipe characterized in that the transverse angle of the lower reinforcing layer is 60° or more and less than 90°, and the transverse angle of the upper reinforcing layer is 45° or more and less than 90°.

[0023] In addition, the present invention provides a hydrogen transport pipe characterized by comprising one or more types selected from the group consisting of the polymer resin, ultra-high molecular weight polyethylene (UHMWPE), high-density polyethylene (HDPE), medium-density polyethylene (MDPE), linear low-density polyethylene (LLDPE), low-density polyethylene (LDPE), polypropylene (PP), ethylene-propylene rubber (EPDM), styrene-butadiene rubber (SBR), chloroprene rubber (CR), nitrile-butadiene rubber (NBR), polytetrafluoroethylene (PTFE), polyvinylidene fluoride (PVDF), fluorocarbon rubber (FKM), silicon rubber, polyvinyl chloride (PVC), maleic anhydride-grafted polyolefin, ethylene vinyl alcohol (EVOH), and polyamide (PA11, PA12).

[0024] In addition, the present invention provides a hydrogen transport pipe characterized in that the reinforcing fiber comprises one or more types selected from the group consisting of carbon fiber, aramid fiber, glass fiber, metal fiber, ultra-high molecular weight polyethylene fiber, nylon fiber, and basalt fiber.

[0025] Herein, a hydrogen transport pipe is provided, characterized in that the reinforcing fibers of the fiber-reinforced polymer tape forming the lower reinforcing layer include glass fibers, and the reinforcing fibers of the fiber-reinforced polymer tape forming the upper reinforcing layer include aramid fibers.

[0026] Furthermore, the present invention provides a hydrogen transport pipe characterized in that the liner is made of a polymer material and additionally includes a hydrogen blocking layer between the liner and the lower reinforcing layer.

[0027] Meanwhile, a hydrogen transport pipe is provided, characterized by additionally including a jacket formed on the outside of an upper reinforcing layer.

[0028] The hydrogen transport piping according to the present invention satisfies not only high pressure resistance of 40 bar or more but also excellent bending characteristics through a reinforcing layer of a new material and structure, and exhibits excellent effects that can reduce installation costs.

[0029] FIG. 1 schematically illustrates the structure of one embodiment of a hydrogen transport pipe according to the present invention.

[0030] FIG. 2 schematically illustrates the structure of another embodiment of a hydrogen transport pipe according to the present invention.

[0031] FIG. 3 schematically illustrates the structure of another embodiment of a hydrogen transport pipe according to the present invention.

[0032] Figure 4 schematically illustrates the configuration of the tape forming each of the lower and upper reinforcing layers shown in Figure 1.

[0033] Figure 5 illustrates an example of measuring the average spacing distance between reinforcing fibers and compensating fiber yarns in the cross-section of the tape forming each of the lower and upper reinforcing layers shown in Figure 4.

[0034] Figure 6 schematically illustrates the appearance of a tape forming a lower reinforcing layer of a hydrogen transport pipe shown in Figure 1 being wound transversely.

[0035] Figure 7 is a drawing showing the transverse winding angle when the tape forming each of the lower and upper reinforcing layers shown in Figure 3 is transversely wound.

[0036] Hereinafter, preferred embodiments of the present invention will be described in detail. However, the present invention is not limited to the embodiments described herein and may be embodied in other forms. Rather, the embodiments introduced herein are provided to ensure that the disclosed content is thorough and complete, and to ensure that the spirit of the present invention is sufficiently conveyed to those skilled in the art. Throughout the specification, the same reference numerals indicate the same components.

[0037] FIGS. 1 to 3 schematically illustrate the structures of embodiments of a hydrogen transport pipe according to the present invention.

[0038] As illustrated in FIG. 1, a hydrogen transport pipe according to the present invention may include a liner (100) which is a tube-shaped pipe body having a hydrogen transport path formed inside, a hydrogen blocking layer (150) formed on the outside of the liner (100), a reinforcing layer (200, 300) formed on the outside of the hydrogen blocking layer (150), a jacket (400) formed on the outside of the reinforcing layer (200, 300), and the reinforcing layer (200) may include a lower reinforcing layer (200) and an upper reinforcing layer (300) formed on the outside of the lower reinforcing layer (200).

[0039] Additionally, as shown in FIG. 2, the upper reinforcing layer (300) may include a first upper reinforcing layer (310) surrounding the lower reinforcing layer (200) and a second upper reinforcing layer (320) surrounding the first upper reinforcing layer (310), and as shown in FIG. 3, the lower reinforcing layer (200) may include a first lower reinforcing layer (210) surrounding the hydrogen blocking layer (150) and a second lower reinforcing layer (220) surrounding the first lower reinforcing layer (210).

[0040] Here, the lower reinforcing layer (200) performs the function of uniformly dispersing the pressure applied to the liner (100) and transmitting it to the upper reinforcing layer (300), and the upper reinforcing layer (300) can perform the function of improving strength and bending characteristics.

[0041] The above liner (100) may be formed in a tube shape in which a channel for transporting hydrogen is formed inside, and although not particularly limited, it may be made of a metal material such as carbon steel, stainless steel, or aluminum, or a plastic material such as high-density polyethylene (HDPE), linear low-density polyethylene (LLDPE), low-density polyethylene (LDPE), medium-density polyethylene (MDPE), ultra-high molecular weight polyethylene (UHMWPE), polypropylene (PP), ethylene propylene rubber (EPDM), styrene-butadiene rubber (SBR), nitrile-butadiene rubber (NBR), polytetrafluoroethylene (PTFE), polyvinylidene fluoride (PVDF), fluorocarbon rubber (FKM), silicone rubber, polyamide (PA11, PA12, PA6, PA66), polyphenylene sulfide (PPS), polyketone (Polyketon), or polyether-etherketone (PEEK).

[0042] In addition, if the liner (100) is made of a plastic material, a hydrogen blocking layer (150) may be additionally formed on the outside of the liner (100). The hydrogen blocking layer (150) has a hydrogen permeability coefficient of 5 cm at 25°C and 1.5 bar. 3 ·cm / (m 2 It may include a single layer or a multilayer made of a material having a temperature of 24hr·atm or less, such as a polymer material such as ethylene vinyl alcohol (EVOH) or a metal material such as aluminum or copper.

[0043] Here, the hydrogen permeability of all layers included in the hydrogen blocking layer (150) is 5 cm 3 ·cm / (m 2 If the rate exceeds 24hr·atm, there is a problem in that the hydrogen cutoff performance for long-distance hydrogen transport cannot be satisfied, or the flexibility and bendability of the pipes are reduced as the pipe thickness increases to satisfy the hydrogen cutoff performance.

[0044] In addition, the hydrogen blocking layer (150) may have different thickness and number of stacked layers depending on the material constituting it, and the thickness may be, for example, 0.01 to 2 mm, preferably 0.01 to 1 mm when made of a metal material, and 0.1 to 2 mm when made of a polymer resin material.

[0045] Furthermore, if the hydrogen blocking layer (150) is made of a metal material such as aluminum or copper, the metal material may be applied in the form of a foil or tape.

[0046] Meanwhile, in the case of metal foil or tape, the overlapping portion can be wound transversely such that the width of the overlapping portion is 1 mm or more, preferably 10 mm or more. If the width of the overlapping portion is less than 1 mm, it is difficult to secure sufficient adhesion between the foil or tape, resulting in reduced hydrogen barrier performance. On the other hand, as the width of the overlapping portion increases, the adhesion between the foil or tape and hydrogen barrier performance are excellent, but there is a problem of increased manufacturing costs due to excessive use of material. Specifically, the adhesion of the overlapping portion in the metal foil or tape is suitable to be 0.5 kgf or more, preferably 1 kgf or more, and if the adhesion is less than 0.5 kgf, a problem may occur where the overlapping portion detaches during bending.

[0047] In addition, the hydrogen blocking layer (150) is preferably a polymer resin such as EVOH with a tensile strength of 10 MPa or more, and preferably a metal material with a tensile strength of 30 MPa or more. Furthermore, the elongation rate of the hydrogen blocking layer (150) is preferably 3% or more. Here, if the elongation rate of the hydrogen blocking layer (150) made of the metal material is less than 3%, a problem may occur in which cracks or breakage may occur due to elongation caused by bending.

[0048] In addition, when the hydrogen blocking layer (150) is made of copper, if it contains a large amount of oxygen, it reacts with hydrogen and becomes susceptible to hydrogen embrittlement; therefore, it is preferable to use oxygen-free copper for the copper.

[0049] The above hydrogen permeability can be calculated using the following mathematical formulas 1 and 2 based on data measured according to standards ISO 2782-1 and ISO 15105-1.

[0050] [Mathematical Formula 1]

[0051] P = GTR × d

[0052] [Mathematical Formula 2]

[0053] GTR=(V c / R·T·P u ·A)×dP / dt

[0054] Figure 4 schematically illustrates the configuration of the tapes forming the lower reinforcing layer and the upper reinforcing layer, respectively, of the hydrogen transport pipe shown in Figure 1.

[0055] Specifically, as shown in FIG. 4a, the lower reinforcing layer (200) may be made of a fiber-reinforced composite material in which reinforcing fibers are spread out and arranged in the width direction of the tape within a tape-shaped polymer resin (201), and as shown in FIG. 4b, the upper reinforcing layer (300) may be made of a fiber-reinforced polymer composite material in which reinforcing fiber yarns (302) shown in FIG. 4c are arranged spaced apart from each other in the width direction of the tape within a tape-shaped polymer resin (301), for example, the fiber-reinforced polymer composite material may be a fiber-reinforced polymer tape, and the lower reinforcing layer (200) and the upper reinforcing layer (300) may be formed by the transverse winding of the fiber-reinforced polymer tape.

[0056] In particular, the reinforcing fiber yarn (302) is formed by twisting and combining multiple reinforcing fibers (302a), and the ovality of each of the multiple reinforcing fiber yarns (302), which is the short diameter / long diameter, may be about 0.5 or more. In each of the multiple reinforcing fiber yarns (302), the area ratio of the void, which is the ratio of the area of ​​the empty space not filled with polymer resin (301) based on the total cross-sectional area of ​​the space between adjacent reinforcing fibers bordered by a virtual circle that contacts the outermost reinforcing fibers among the reinforcing fibers constituting each of the reinforcing fiber yarns (302) in any cross-section, is about 50% or more, for example, 50 to 80%, thereby maximizing the flexibility of the hydrogen transport pipe.

[0057] The above reinforcing fiber yarn (302) can be manufactured by extruding the combined reinforcing fibers into a polymer resin (301), and the area ratio of the voids can be controlled by the degree to which the polymer resin (301) penetrates toward the center of the combined reinforcing fibers during extrusion, and, for example, the area ratio of the voids can be controlled by controlling the viscosity, melt index, etc. of the polymer resin (301) or by controlling the pressure during extrusion.

[0058] Here, if the area ratio of the above voids is less than 50%, the polymer resin (301) penetrates excessively between the reinforcing fibers, increasing the frictional force between the reinforcing fibers when bent, making it difficult for them to move separately, and consequently, the flexibility of the hydrogen transport pipe may be reduced, whereas if the area ratio of the above voids is more than 80%, it is difficult for the reinforcing fibers to maintain a stable bonded state by the polymer resin (301), and consequently, the high pressure resistance of the hydrogen transport pipe may be reduced.

[0059] Additionally, preferably, heat is applied through a hot air blower or the like during the transverse winding of the fiber-reinforced polymer tape, and heat is applied through an IR heater or the like after the transverse winding is completed, so that the polymer resin forming the fiber-reinforced polymer tape is partially melted and thus firmly fused to the lower liner (100), hydrogen barrier layer (150), reinforcing layer (200, 300), etc.

[0060] Furthermore, the transverse winding of the fiber-reinforced polymer tape can preferably be performed by wrapping so as to overlap by 5% or less based on the width of the fiber-reinforced polymer tape, or by gap winding so as to form a gap of 3 mm or less.

[0061] Here, if the overlap ratio exceeds 5% when wrapping, the appearance of the pipe may be uneven, and the bending characteristics of the pipe for hydrogen transport may be degraded, and if the gap exceeds 3 mm when wrapping, the reinforcing characteristics of the reinforcing layer may be insufficient.

[0062] Here, the polymer resin forming the fiber-reinforced polymer composite material may include one or more polymer resins selected from the group consisting of ultra-high molecular weight polyethylene (UHMWPE), high-density polyethylene (HDPE), medium-density polyethylene (MDPE), linear low-density polyethylene (LLDPE), low-density polyethylene (LDPE), polypropylene (PP), ethylene-propylene rubber (EPDM), styrene-butadiene rubber (SBR), chloroprene rubber (CR), nitrile-butadiene rubber (NBR), polytetrafluoroethylene (PTFE), polyvinylidene fluoride (PVDF), fluorocarbon rubber (FKM), silicon rubber, polyvinyl chloride (PVC), maleic anhydride-grafted polyolefin, ethylene vinyl alcohol (EVOH), polyamide (PA11, PA12), etc.

[0063] However, it is preferable that the melting index (MI) of the polymer resin (201) applied to the fiber-reinforced polymer tape forming the lower reinforcing layer (200) is greater than the melting index (MI) of the polymer resin (301) applied to the fiber-reinforced polymer tape forming the upper reinforcing layer (300).

[0064] Additionally, the reinforcing fibers arranged in the polymer resin (201) of the lower reinforcing layer (200) and the reinforcing fiber yarn (302) arranged in the polymer resin (301) of the upper reinforcing layer (300) may each independently include one or more reinforcing fibers selected from the group consisting of carbon fibers, aramid fibers, glass fibers, metal fibers, ultra-high molecular weight polyethylene fibers, nylon fibers, basalt fibers, etc., and preferably may include glass fibers or aramid fibers.

[0065] In the case where the fiber-reinforced polymer composite material is a fiber-reinforced polymer tape, the reinforcing fibers (202) and reinforcing fiber yarns (302) arranged in the polymer resin (201, 301) can all be extended in the same direction, and, for example, can be extended in the length direction of the tape to achieve a sufficient reinforcing effect.

[0066] Specifically, the fiber-reinforced polymer tape forming the lower reinforcing layer (200) can be manufactured by spreading a plurality of reinforcing fibers (202) densely in the width direction of the tape and arranging them within a tape-shaped polymer resin (201) in an extended state along the length direction of the tape, and thus, adjacent reinforcing fibers (202) in the lower reinforcing layer (200) can be arranged at a relatively denser spacing than the spacing of the reinforcing fiber yarns (302) of the upper reinforcing layer (300).

[0067] Additionally, the plurality of reinforcing fibers (202) are not intentionally twisted together, but may exist in the form of bundles that are unintentionally separated during the process of unfolding in the width direction of the tape, that is, may include one or more reinforcing fiber bundles in which two or more reinforcing fibers are assembled.

[0068] Meanwhile, the fiber-reinforced polymer tape forming the upper reinforcing layer (300) can be manufactured by arranging multiple reinforcing fiber yarns (302), each formed by twisting multiple reinforcing fibers (302a) together, at intervals along the width direction of the tape and extending along the length direction of the tape, within a polymer resin (301) in the shape of a tape, and adjacent reinforcing fiber yarns (302) can be arranged at intervals that are relatively wider than the spacing of the reinforcing fibers (202) of the lower reinforcing layer (200).

[0069] Additionally, based on the total weight of the fiber-reinforced polymer tape forming the lower reinforcing layer (200), the total weight of the reinforcing fiber (202) may be 30 to 90 weight percent. Here, if the total weight of the reinforcing fiber (202) is less than 30 weight percent, the reinforcing performance of the lower reinforcing layer (200) may be insufficient, whereas if it exceeds 90 weight percent, the amount of polymer resin (201) is insufficient, so the fusion with the liner (100) or hydrogen blocking layer (150) may be insufficient.

[0070] Additionally, the reinforcing fiber yarn (302) may have a tex of 440 to 16,000. Here, tex refers to the g of a reinforcing fiber yarn with a length of 1 km. If the tex of the reinforcing fiber yarn (302) is less than 440, flexibility is improved but strength is below the standard, whereas if the tex of the reinforcing fiber yarn (302) is greater than 16,000, strength is improved but flexibility may be below the standard.

[0071] In addition, based on the total weight of the fiber-reinforced polymer tape forming the upper reinforcing layer (300), the total weight of the reinforcing fiber yarn (302) may be 30 to 90 weight%. Here, if the total weight of the reinforcing fiber yarn (302) is less than 30 weight%, the reinforcing performance of the second reinforcing layer (300) may be insufficient, whereas if it exceeds 90 weight%, the amount of polymer resin (301) is insufficient, so a problem may occur in forming the tape or the fusion with the lower reinforcing layer (200) may be insufficient.

[0072] FIG. 5 illustrates an example of measuring the average spacing of reinforcing fibers (202) and reinforcing fiber yarns (302) in a cross-section of a tape forming each of the lower and upper reinforcing layers shown in FIG. 1.

[0073] As shown in FIG. 5a, the average spacing of the reinforcing fibers (202) in the cross-section of the tape forming the lower reinforcing layer (200) can be calculated as the average value of the horizontal distances between adjacent reinforcing fibers, and as shown in FIG. 5b, the average spacing of the reinforcing fiber yarns (302) in the cross-section of the tape forming the upper reinforcing layer (300) can be calculated as the average value of the horizontal distances between adjacent reinforcing fiber yarns (302).

[0074] Specifically, the average spacing of the reinforcing fibers (202) is the horizontal distance between adjacent reinforcing fibers, a1, a2, a3… a n The total sum can be calculated by dividing it by the total number of reinforcing fibers minus 1, and the average spacing distance of the reinforcing fiber yarns (302) is the horizontal distance between adjacent reinforcing fiber yarns (302), b1, b2, b3… b n The total sum can be calculated by dividing the total number of reinforcing fiber yarns (302) by -1.

[0075] Here, the average spacing of the reinforcing fibers (202) in the cross-section of the tape forming the lower reinforcing layer (200) is designed to be shorter than the average spacing of the reinforcing fiber yarns (302) in the cross-section of the tape forming the upper reinforcing layer (300), that is, the reinforcing fibers of the lower reinforcing layer (200) are arranged densely in the width direction of the tape, so that the lower reinforcing layer (200) can smoothly perform the function of uniformly dispersing the pressure applied to the liner (100) and transmitting it to the upper reinforcing layer (300), and the upper reinforcing layer (300) can smoothly perform the function of improving strength and bending characteristics.

[0076] Furthermore, the thickness (t1) of the tape forming the lower reinforcing layer (200) may be smaller than the thickness (t2) of the tape forming the upper reinforcing layer (300), and the height (h1) of each reinforcing fiber or reinforcing fiber bundle in the tape forming the lower reinforcing layer (200) may be about 0.3 mm or less, and the height (h2) of each reinforcing fiber yarn (302) in the tape forming the upper reinforcing layer (300) may be about 0.5 mm or more, preferably about 0.5 to 1.5 mm.

[0077] Meanwhile, the jacket (400) may be made of a material having a melting point of 50°C or higher, preferably 70°C or higher, such as high-density polyethylene (HDPE), medium-density polyethylene (MDPE), linear low-density polyethylene (LLDPE), low-density polyethylene (LDPE), ethylene vinyl acetate (EVA), ethylene acetate (EEA), polyolefin elastomer (POE), thermoplastic polyethylene (TPE), etc.

[0078] Here, if the melting point of the jacket (400) is less than 50°C, the heat resistance is low, and problems may occur where the jacket (400) deteriorates or fails to maintain its shape during long-term use. Additionally, the brittleness temperature of the jacket (400) may be -5°C or lower, preferably -10°C or lower, thereby providing excellent cold resistance. Here, if the brittleness temperature of the jacket (400) exceeds -5°C, cracks may occur in the jacket (400) in cold environments such as winter.

[0079] The above brittleness temperature can be measured by the following mathematical formula 3 in accordance with the ASTM D746 standard.

[0080] [Mathematical Formula 3]

[0081] T b =T h +△T[(S / 100)-(1 / 2)]

[0082] In the above mathematical formula 3, T b is the brittleness temperature, T h θ is the highest temperature at which the specimen breaks during the cold resistance evaluation test, ΔT is the change in temperature during the cold resistance evaluation test, and S is the sum of the percentages of specimens broken at each test temperature.

[0083] FIG. 6 schematically illustrates the formation of a lower reinforcing layer in a liner in FIG. 3, and FIG. 7 is a drawing showing the transverse winding angle when the tape forming each of the lower and upper reinforcing layers shown in FIG. 3 is transversely wound.

[0084] As illustrated in FIG. 6, the lower reinforcing layer (200) may include a first lower reinforcing layer (210) surrounding the liner (100) or the hydrogen blocking layer (150) and a second lower reinforcing layer (220) surrounding the first lower reinforcing layer (210), and the first and second lower reinforcing layers (210, 220) may both be formed by the transverse winding of a fiber-reinforced polymer tape, but the transverse winding directions of the fiber-reinforced polymer tapes forming each of the first and second lower reinforcing layers (210, 220) may be different from each other.

[0085] For example, when the fiber-reinforced polymer tape forming the first lower reinforcing layer (210) is wound in the S direction, the fiber-reinforced polymer tape forming the second lower reinforcing layer (220) is wound in the Z direction, and when the fiber-reinforced polymer tape forming the first lower reinforcing layer (210) is wound in the Z direction, the fiber-reinforced polymer tape forming the second lower reinforcing layer (220) is wound in the S direction.

[0086] Additionally, the transverse winding angle (θ1) of the fiber-reinforced polymer tape forming the lower reinforcing layer (200), that is, the angle at which the fiber-reinforced polymer tape is tilted relative to the central axis of the hydrogen transport pipe, may be 60° or more and less than 90°. Here, if the transverse winding angle (θ1) is less than 60°, the reinforcing characteristics of the lower reinforcing layer (200) may be insufficient.

[0087] The bending characteristics of the hydrogen transport pipe can be improved by applying different transverse winding directions of the fiber-reinforced polymer tapes forming each of the first and second lower reinforcing layers (210, 220).

[0088] In addition, the transverse winding directions of the fiber-reinforced polymer tapes forming the first and second upper reinforcing layers (310, 320) are different from each other. This allows the bending characteristics of the hydrogen transport pipe to be improved.

[0089] For example, when the fiber-reinforced polymer tape forming the first upper reinforcing layer (310) is wound in the S direction, the fiber-reinforced polymer tape forming the second upper reinforcing layer (320) is wound in the Z direction, and when the fiber-reinforced polymer tape forming the first upper reinforcing layer (310) is wound in the Z direction, the fiber-reinforced polymer tape forming the second upper reinforcing layer (320) is wound in the S direction.

[0090] Additionally, the transverse winding angle (θ2) of the fiber-reinforced polymer tape forming the upper reinforcing layer (300), that is, the angle at which the fiber-reinforced polymer tape is tilted relative to the central axis of the hydrogen transport pipe, may be 45° or more and less than 90°. Here, if the transverse winding angle (θ2) is less than 45°, the reinforcing characteristics of the upper reinforcing layer (300) may be insufficient.

[0091] The hydrogen transport piping according to the present invention can achieve high pressure resistance of 40 bar or more and sufficient bending characteristics through the combination of the upper and lower reinforcing layers described above, and furthermore, installation costs can be reduced.

[0092] Although this specification has been described with reference to preferred embodiments of the present invention, those skilled in the art may modify and change the present invention in various ways without departing from the spirit and scope of the present invention as described in the claims below. Therefore, if a modified embodiment basically includes the components of the claims of the present invention, it should be considered to be included within the technical scope of the present invention.

Claims

1. As a pipeline for hydrogen transfer, A tube-shaped liner having a hydrogen transport channel formed inside; and It includes a reinforcing layer formed on the outside of the above liner, and The above reinforcing layer comprises a reinforcing layer formed by the transverse winding of a fiber-reinforced polymer tape in which a plurality of reinforcing fiber yarns are arranged within a tape-shaped polymer resin, and A hydrogen transport pipe, wherein each of the above-mentioned plurality of reinforcing fiber yarns is formed by twisting and combining a plurality of reinforcing fibers, and the void area ratio, which is the ratio of the area of ​​the empty space not filled with the polymer resin based on the total cross-sectional area of ​​the space between adjacent reinforcing fibers bordered by a virtual circle contacting the outermost reinforcing fibers among the plurality of reinforcing fibers constituting each of the above-mentioned reinforcing fiber yarns in any cross-section, is 50% or more.

2. In Paragraph 1, A hydrogen transport pipe characterized by having an area ratio of 50 to 80% of the above-mentioned voids.

3. In Paragraph 1 or 2, A hydrogen transport pipe characterized by the fact that the ovality of each of the plurality of reinforcing fiber yarns, specifically the short diameter / long diameter, is 0.5 or greater.

4. In Paragraph 1 or 2, The reinforcing layer comprises at least one lower reinforcing layer and at least one upper reinforcing layer formed outside the lower reinforcing layer, The lower reinforcing layer is formed by the transverse winding of a fiber-reinforced polymer tape in which a plurality of reinforcing fibers are arranged within a tape-shaped polymer resin, and the plurality of reinforcing fibers are extended along the longitudinal direction of the tape and spread out and arranged in the width direction of the tape. A hydrogen transport pipe characterized in that the upper reinforcing layer is formed by the transverse winding of a fiber-reinforced polymer tape in which a plurality of reinforcing fiber yarns are arranged within a tape-shaped polymer resin, and the plurality of reinforcing fiber yarns extend along the longitudinal direction of the tape and are arranged spaced apart from each other in the width direction of the tape.

5. In Paragraph 4, The average spacing between multiple reinforcing fibers of the fiber-reinforced polymer tape forming the lower reinforcing layer is shorter than the average spacing between multiple reinforcing fiber yarns of the fiber-reinforced polymer tape forming the upper reinforcing layer, and A hydrogen transport pipe characterized in that the average spacing between the plurality of reinforcing fibers is the average value of the horizontal distances between adjacent reinforcing fibers, and the average spacing between the plurality of reinforcing fiber yarns is the average value of the horizontal distances between adjacent reinforcing fiber yarns.

6. In Paragraph 4, A hydrogen transport pipe characterized in that the thickness of the fiber-reinforced polymer tape forming the lower reinforcing layer is smaller than the thickness of the fiber-reinforced polymer tape forming the upper reinforcing layer.

7. In Paragraph 4, In the fiber-reinforced polymer tape forming the lower reinforcing layer, a plurality of reinforcing fibers may include one or more reinforcing fiber bundles formed by assembling two or more strands of reinforcing fibers, and A hydrogen transport pipe characterized in that the height of each of the above reinforcing fibers or reinforcing fiber bundles is 0.3 mm or less.

8. In Paragraph 7, A hydrogen transport pipe characterized in that the height of each of the plurality of reinforcing fiber yarns in the fiber-reinforced polymer tape forming the upper reinforcing layer is 0.5 mm or more.

9. In Paragraph 4, The upper reinforcing layer includes a first upper reinforcing layer formed outside the lower reinforcing layer and a second upper reinforcing layer formed outside the first upper reinforcing layer, A hydrogen transport pipe characterized by the fact that the transverse winding directions of the fiber-reinforced polymer tapes forming each of the first upper reinforcing layer and the second upper reinforcing layer are different.

10. In Paragraph 4, The lower reinforcing layer comprises a first lower reinforcing layer formed on the outside of the liner and a second lower reinforcing layer formed on the outside of the first lower reinforcing layer. A hydrogen transport pipe characterized by the fact that the transverse winding directions of the fiber-reinforced polymer tapes forming each of the first lower reinforcing layer and the second lower reinforcing layer are different.

11. In Paragraph 4, A hydrogen transport pipe characterized in that, based on the total weight of the fiber-reinforced polymer tape, the total weight of the reinforcing fiber and the reinforcing fiber yarn is 30 to 90 weight percent.

12. In Paragraph 4, A hydrogen transport pipe characterized in that the above reinforcing fiber yarn has a tex of 440 to 16,000.

13. In Paragraph 4, A hydrogen transport pipe characterized in that the transverse angle of the lower reinforcing layer is greater than the transverse angle of the upper reinforcing layer.

14. In Paragraph 4, A hydrogen transport pipe characterized by the transverse bending angle of the lower reinforcing layer being 60° or more and less than 90°, and the transverse bending angle of the upper reinforcing layer being 45° or more and less than 90°.

15. In Paragraph 4, A hydrogen transport pipe characterized by comprising one or more types selected from the group consisting of the above polymer resins: ultra-high molecular weight polyethylene (UHMWPE), high-density polyethylene (HDPE), medium-density polyethylene (MDPE), linear low-density polyethylene (LLDPE), low-density polyethylene (LDPE), polypropylene (PP), ethylene-propylene rubber (EPDM), styrene-butadiene rubber (SBR), chloroprene rubber (CR), nitrile-butadiene rubber (NBR), polytetrafluoroethylene (PTFE), polyvinylidene fluoride (PVDF), fluorocarbon rubber (FKM), silicon rubber, polyvinyl chloride (PVC), maleic anhydride-grafted polyolefin, ethylene vinyl alcohol (EVOH), and polyamide (PA11, PA12).

16. In Paragraph 4, A hydrogen transport pipe characterized by comprising one or more types selected from the group consisting of carbon fibers, aramid fibers, glass fibers, metal fibers, ultra-high molecular weight polyethylene fibers, nylon fibers, and basalt fibers.

17. In Paragraph 16, The reinforcing fibers of the fiber-reinforced polymer tape forming the lower reinforcing layer include glass fibers, and A hydrogen transport pipe characterized in that the reinforcing fibers of the fiber-reinforced polymer tape forming the upper reinforcing layer include aramid fibers.

18. In Paragraph 4, The above liner is made of a polymer material, and A hydrogen transport pipe characterized by additionally including a hydrogen blocking layer between the above liner and the above lower reinforcing layer.

19. In Paragraph 4, A hydrogen transport pipe characterized by additionally including a jacket formed on the outside of an upper reinforcing layer.

Images