Multi-layer pipeline, use thereof, and method for installing a pipeline of this kind

Abstract

The invention relates to a multi-layer pipeline (1, 1', 1'') for conducting a fluid, wherein the multi-layer pipeline (1, 1', 1'') comprises at least the following layers: a) an inner layer (2, 2', 2'', 2'''), which forms an inner pipe for conducting the fluid, b) an insulation layer (3) surrounding the inner layer (2, 2', 2'', 2'''), wherein the insulation layer (3) is arranged on a side of the inner layer (2, 2', 2'', 2''') further away from a central line of the inner pipe, and c) an outer layer (4) surrounding the insulation layer (3), wherein the outer layer is arranged on a side of the insulation layer (3) further away from the central line of the inner pipe, and wherein at least 50%, in particular at least 70%, in particular at least 90% and preferably 100% of the side of the outer layer (4) adjoining the insulation layer (3) is non-integrally bonded to the insulation layer (3) and / or is movable relative to the insulation layer (3). The invention also relates to a use of the multi-layer pipeline (1, 1', 1'') for connecting a hot water heating system (15) to a heat pump (12) and to a method for installing the multi-layer pipeline (1, 1', 1'').

Description

[0001] MULTI-LAYER PIPELINE, ITS USE AND METHODS FOR LAYING SUCH A PIPELINE

[0002] Technical area

[0003] The invention relates to a multilayer pipeline for carrying a fluid, a use of the multilayer pipeline for connecting a hot water heating system to a heat pump, and a method for laying the multilayer pipeline.

[0004] State of the art

[0005] Multi-layer pipelines for conveying a fluid are frequently encountered in the prior art, whereby the different layers of the multi-layer pipelines known from the prior art serve for insulation purposes or for mechanical stabilization or to prevent damage to the pipeline.

[0006] During the construction of a new building, empty pipes are often laid in the house or in the immediate vicinity to allow for the later installation of, for example, a new heating system without requiring major retrofitting work on the house or its surroundings. A pipe connecting a newly installed heat pump to an existing hot water heating system can, in particular, be laid through an already laid empty pipe, allowing for easy retrofitting of a heat pump.

[0007] However, state-of-the-art multilayer pipelines are designed in such a way that routing them through an already installed pipe is difficult and, in particular, requires considerable physical effort from the installer. This makes the subsequent installation of a heat pump, which, for example, is to be installed at a considerable distance from a house due to noise pollution, difficult, as the multilayer pipelines sometimes have to be pulled through empty pipes several meters long, especially those more than ten meters long, especially underground pipes in the ground.

[0008] Description of the invention

[0009] It is therefore an object of the invention to provide a multilayer pipeline that eliminates at least some of the disadvantages of prior art multilayer pipelines. In particular, the pipeline should be as easy to retract into empty conduits as possible while being protected from damage.

[0010] The solution to the problem is defined by the features of claims 1, 12 and 14.According to a first aspect of the invention, the invention relates to a multi-layer pipeline for conducting a fluid, wherein the multi-layer pipeline has at least the following layers: a) an inner layer which forms an inner tube for conducting the fluid, b) an insulation layer surrounding the inner layer, wherein the insulation layer is arranged on a side of the inner layer facing away from a center line of the inner tube, and c) an outer layer surrounding the insulation layer, wherein the outer layer is arranged on a side of the insulation layer facing away from the center line of the inner tube, and wherein the outer layer is not materially connected to the insulation layer on at least 50%, in particular at least 70%, in particular at least 90% and preferably on 100% of its side adjacent to the insulation layer and / or is movable relative to the insulation layer.The side of the outer layer adjacent to the insulation layer can also be referred to as the inner surface. The term "relatively movable" is understood in particular to mean that, under the influence of shear forces acting on the outer layer, it can move relative to the insulation layer in such a way that the acting shear forces are essentially dissipated via the moving outer layer and essentially do not affect the insulation layer.The outer layer is preferably constructed in such a way that at every point of the outer layer, particularly in areas not bonded to the insulation layer, movement relative to the insulation layer in all directions (for example, relative to a tangential plane defined at the corresponding point) along the surface of the insulation layer is possible, so that shear forces acting from different directions can be absorbed in such a way that no significant forces act on the insulation layer. Advantageously, damage, in particular tearing, of the insulation layer due to acting shear forces can thus be prevented or reduced.

[0011] The inner layer is preferably designed so that the guided fluid does not leak out, i.e., the inner layer is preferably designed to be sealed. Furthermore, the inner layer is preferably designed so that it is chemically resistant to the conveyed fluid, for example, water or a water-glycol mixture, and that it is sufficiently heat-resistant, depending on the application.

[0012] The multi-layer pipe is preferably also designed such that it is essentially metal-free, so that the multi-layer pipeline can be processed more easily. For example, an essentially metal-free multi-layer pipeline can be shortened more easily at one end, and the inner pipe can be connected, for example, via a clamp to a connection of a hot water heating system or a heat pump. In contrast to an inner pipe made of metal, an essentially metal-free inner pipe therefore allows for simplified connection, since, for example, a welding step can be omitted. The term "center line" is to be understood in particular to mean an imaginary line that extends in the longitudinal direction, following a main direction of extension of the inner pipe, and that runs through the center point of the interior of the inner pipe.In the case of an inner tube as a hollow cylinder, for example, the center point is in the middle of the inner diameter of the hollow cylinder.

[0013] The insulation layer is preferably designed and dimensioned to enable sufficient thermal insulation between an interior of the inner tube and an environment, so that, for example, a warm fluid in the inner tube is not cooled too much by a colder environment and vice versa.

[0014] According to one embodiment of the multi-layer pipeline according to the invention, the inner layer contains rubber, and / or the insulation layer is formed as polyurethane foam and / or as ethylene-propylene-diene rubber foam (EPDM foam), and / or the outer layer is formed as a textile fabric.

[0015] The insulation layer can generally be formed as a foamed polymer material, with polyurethane foam and / or EPDM foam being preferred materials. A "polymer" is understood here to mean, in particular, an organic polymer.

[0016] According to a further embodiment of the multi-layer pipeline according to the invention, the textile fabric is designed as a polyamide fabric, in particular comprising polyamide of the type PA 6.

[0017] The textile fabric can generally be designed as a polymer fabric, with polyamide fabrics, in particular PA 6, being preferred materials.

[0018] Polyamide possesses good sliding properties, high wear resistance, and high abrasion resistance. An outer layer constructed of polyamide fabric can therefore advantageously slide easily over the insulation layer, protecting it from damage caused by shear forces that can occur, for example, during the installation of the multilayer pipeline. An outer layer constructed of polyamide fabric can also advantageously slide easily through an already installed conduit, making it easier to pass a multilayer pipeline with an outer layer constructed of polyamide fabric through an already installed conduit.

[0019] The textile fabric can also be designed as a knitted or crocheted fabric, as a braid or as a scrim.

[0020] According to a further embodiment of the multi-layer pipeline according to the invention, the multi-layer pipeline is circular-cylindrical in an unbent state, wherein the inner pipe and the insulation layer are each hollow-cylindrical.

[0021] In an unbent state, which may be present in particular before the multilayer pipeline is laid and connected, the pipeline may be circularly cylindrical and extend substantially along the main extension direction of the inner pipe or the multilayer pipeline. After the multilayer pipeline has been laid and connected, e.g., to a heat pump or a hot water heating system, the multilayer pipeline may generally be bent and, in some cases, slightly deformed. A hollow-cylindrical inner pipe may be arranged inside a hollow-cylindrical insulation layer.

[0022] According to a further embodiment of the multi-layer pipeline according to the invention, the inner layer is not materially connected to the insulation layer on at least 50%, in particular on at least 70%, in particular on at least 90% and preferably on 100% of its side adjacent to the insulation layer.

[0023] The side of the inner layer adjacent to the insulation layer can also be referred to as the outer surface. In the case of an inner layer formed as a hollow cylinder, the side of the inner layer adjacent to the insulation layer corresponds to the outer surface of the inner layer. A non-adhesive connection between the insulation layer and the inner layer can offer the advantage of improved mobility of the multi-layer pipeline, as the inner layer and the insulation layer can partially move against each other. This can further simplify the installation and connection of the multi-layer pipeline.

[0024] According to a further embodiment of the multi-layer pipeline according to the invention, the inner diameter of the insulation layer is between 0.2 to 0.6 cm, preferably 0.4 cm, larger than the outer diameter of the inner pipe, and / or the wall thickness of the insulation layer is between 1.8 to 2.5 cm, preferably 2.2 cm.

[0025] More generally, the inner diameter of the insulation layer can also be between 5 to 30%, especially between 10 to 20%, larger than the outer diameter of the inner pipe.

[0026] An inner diameter of the insulation layer that is larger than the outer diameter of the inner pipe results in a gap between the inner pipe and the insulation layer, at least in some sections. Such a gap can also facilitate any bending of the pipe that may be necessary during installation and connection of the multi-layer pipeline. The inner pipe will generally also touch the insulation layer, at least in some sections. Furthermore, such a gap can help prevent material stresses that could arise, for example, due to different thermal expansion behaviors between the inner layer and the insulation layer.

[0027] According to a further embodiment of the multi-layer pipeline according to the invention, the outer surface of the inner pipe is finely structured, in particular corrugated, and the inner surface of the inner pipe is smooth.

[0028] A particularly corrugated outer surface of the inner tube can enable improved contact between the inner layer and the insulation layer at the points where the inner layer and the insulation layer touch. Since the inner tube and the insulation layer can be bonded non-positively, the corrugated outer surface can make it more difficult for the inner tube to slip relative to the insulation layer—particularly in the main expansion direction of the inner tube—thus improving the stability of the multi-layer tube. A smooth inner surface of the inner tube, in turn, can improve the flow behavior of a fluid inside the inner tube.

[0029] According to a further embodiment of the multilayer pipeline according to the invention, the outer diameter of the inner pipe is between 2.3 and 3 cm, preferably 2.5 cm, and / or the inner diameter of the inner pipe is between 1.5 and 1.9 cm, preferably 1.7 cm.

[0030] According to a further embodiment of the multi-layer pipeline according to the invention, the inner layer is formed in three layers, wherein a first layer of the three-layer inner layer is formed as a butyl rubber layer, wherein a second layer of the three-layer inner layer, which is arranged between the first layer and a third layer of the three-layer inner layer, is formed as a textile fabric, in particular comprising nylon fibers, and wherein the third layer is formed as a butyl rubber layer.

[0031] The textile fabric as the second layer of the three-layer inner layer can provide reinforcement of the inner pipe, thereby improving the stability of the multi-layer pipeline.

[0032] According to a further embodiment of the multi-layer pipeline according to the invention, the second layer is formed as a nylon fabric.

[0033] According to a further embodiment of the multi-layer pipeline, the first layer is connected to the second layer and the second layer is connected to the third layer in a materially bonded and / or form-fitting manner.

[0034] According to a further embodiment of the multi-layer pipeline, the inner layer is formed in four layers, wherein a first layer of the four-layer inner layer is formed as a butyl rubber layer, wherein a second layer of the four-layer inner layer, which is arranged between the first layer and a third layer of the four-layer inner layer, is formed as a textile fabric, in particular comprising nylon fibers, wherein the third layer is formed as a butyl rubber layer, and wherein a fourth layer of the four-layer inner layer is arranged between the first layer and the second layer and the second layer is arranged between the fourth layer and the third layer, wherein the fourth layer is formed as an oxygen barrier layer.

[0035] The fourth layer, which is designed as an oxygen barrier layer, can advantageously minimize oxidation of a fluid flowing through the multilayer pipeline. The oxygen barrier layer can be designed such that it has no or very low permeability to gases, in particular oxygen. The multilayer pipeline can be used, for example, to connect a hot water heating system to a heat pump, wherein a water-glycol mixture can flow through the multilayer pipeline. Glycol can decompose upon contact with dissolved oxygen. This decomposition leads to a reduction in the pH value of the fluid in the multilayer pipeline and can thus contribute to damage to the heat pump, the hot water heating system, and / or the multilayer pipeline.The fourth layer, designed as an oxygen barrier layer, can reduce such decomposition, for example, of glycol, and thus extend the service life of the hot water heating system, the heat pump, and the multilayer pipeline. Advantageously, the fourth layer can also form a barrier to water vapor, making it more difficult for water contained in the multilayer pipeline to escape through evaporation. Advantageously, such a fourth layer can also prevent the development of negative pressure in the multilayer pipeline.

[0036] Since essential components of hot water heating systems and heat pumps are often made of unalloyed or only weakly alloyed steels, hot water heating systems and heat pumps are typically susceptible to corrosion. The additional fourth layer prevents oxygen diffusion into the inner pipe, which is designed for the circulation of a fluid, allowing the fluid to remain essentially oxygen-free. Thus, the fourth layer can prevent corrosion in the hot water heating system or heat pump.

[0037] Any corrosion would lead to the buildup of corrosion residues, particularly in the form of sludge deposits. Such sludge deposits, in turn, could contribute to mechanical damage or reduced heat transfer with additional thermomechanical stresses in the material, which could lead to cracks in ferrous materials. Sludge deposits could also contribute to partial overheating, which could cause boiling and stress noises. A fourth layer designed as an oxygen barrier layer can advantageously prevent the formation of sludge deposits.

[0038] The position of the fourth layer and the second layer of the four-layer inner layer can also be interchanged, ie the four-layer inner layer can have the following layer sequence, proceeding from the inner surface of the inner tube towards the outer surface of the inner tube: first layer, second layer, fourth layer and third layer.

[0039] According to a further embodiment of the multi-layer pipeline, the fourth layer is formed as a metallized polyester layer and / or the second layer is formed as a nylon fabric.

[0040] The fourth layer can also be designed differently. Preferably, the fourth layer is made of a material that is flexible and simultaneously has low oxygen permeability.

[0041] According to a further embodiment of the multi-layer pipeline, the first layer is connected to the fourth layer, the fourth layer to the second layer, and the second layer to the third layer, respectively, in a materially bonded and / or form-fitting manner. According to a second aspect of the invention, the invention relates to the use of a multi-layer pipeline according to the first aspect of the invention for connecting a hot water heating system to a heat pump.

[0042] A multilayer pipeline according to the first aspect of the invention can be used to connect a hot water heating system, which may, for example, include underfloor heating in a residential building, to a heat pump, for example in the form of an air-to-water heat pump, a water-to-water heat pump, or a brine-to-water heat pump. In general, the multilayer pipeline can carry other fluids besides water, which can be used instead of water in a hot water heating system and / or a heat pump.

[0043] The heat pump and the hot water heating system can have separate fluid circuits and be connected to each other, for example, via a heat exchanger, which can also be part of the heat pump. A water-based fluid can be conveyed through the multilayer piping, which can be particularly frost-resistant and is preferably a water-glycol mixture.

[0044] The heat pump can be designed as a monoblock heat pump; in particular, the heat pump can also be designed as a split heat pump, whereby one part of the split heat pump can be located outside a house and another part of the heat pump can be located inside the house.

[0045] Since the multilayer pipeline according to the first aspect of the invention can be easily installed due to its nature, in particular the at least partially non-material connection between the insulation layer and the outer layer, it is well suited for retrofitting together with the heat pump. In particular, the multilayer pipeline can be routed more easily through a base pipe already laid, in particular in the ground, in order to connect a heat pump located outside a house to a hot water heating system inside the house. If the multilayer pipeline advantageously consists essentially only of non-metallic materials, the multilayer pipeline can also be connected in a simplified manner.In particular, an installer can simply shorten the pipe as needed and, if the inner pipe is sufficiently flexible, attach it to an external connection, for example by means of a clamp.

[0046] According to one embodiment of the use according to the invention, the multi-layer pipeline is connected to the heat pump and the hot water heating system in such a way that it carries water heated by the heat pump to the hot water heating system or that it carries water cooled by the hot water heating system to the heat pump, wherein the multi-layer pipeline is laid at least partially in a base pipe, in particular laid in the ground.

[0047] To connect a hot water heating system to a heat pump, two multi-layer pipelines can also be advantageously used, wherein a first of the two multi-layer pipelines is connected in such a way that it is designed to carry heated water from the heat pump to the hot water heating system, and wherein a second of the two multi-layer pipelines is connected in such a way that it is designed to carry cooled water from the hot water heating system to the heat pump. The two multi-layer pipelines can be laid together in one main pipe or, alternatively, in separate main pipes.

[0048] According to a third aspect of the invention, the invention relates to a method for laying a multi-layer pipeline according to the first aspect of the invention, comprising the step of inserting the multi-layer pipeline through a base pipe previously laid, in particular in the ground.

[0049] According to one embodiment of the method according to the invention, the step of inserting the multi-layer pipeline comprises the following sub-steps: a) force-fitting a pull-in rope to a first end of the multi-layer pipeline; b) pushing the pull-in rope from a first end of the base pipe to the second end of the base pipe until the pull-in rope leaves the base pipe at the second end; and c) pulling a part of the pull-in rope that has left the base pipe at the second end away from the base pipe and pushing the multi-layer pipeline into the first end of the base pipe towards the second end until the first end of the multi-layer pipeline leaves the second end of the base pipe.

[0050] The frictional fastening of the pull-in rope to the first end of the multi-layer pipeline can be provided by a sleeve-like enclosure of the first end. The pull-in rope is advantageously sufficiently stiff to be easily pushed through base pipes. Furthermore, it must be designed such that it does not tear during step c) of pulling. Furthermore, it is advantageous if the pull-in rope is designed such that it has low friction against the base pipe, so that an installer is not made more difficult to insert the multi-layer pipeline into the base pipe due to excessive friction between the pull-in rope and the base pipe. To facilitate the execution of steps b) and c), the base pipe and / or the outer layer of the multi-layer pipeline can be additionally coated with lubricant, e.g.a lubricant based on grease, silicone and / or tallow, to reduce friction between the multi-layer pipeline or the pull-in rope and the main pipe.

[0051] Further advantageous embodiments and combinations of features of the invention emerge from the following detailed description and the entirety of the patent claims.

[0052] Short description of the drawings

[0053] The drawings used to explain the embodiment show:

[0054] Fig. 1 shows a schematic cross-sectional view through a multi-layer pipeline; Fig. 2 shows a schematic cross-sectional view through another multi-layer pipeline;

[0055] Fig. 3 shows a schematic perspective view of a multi-layer pipeline; and

[0056] Fig. 4 shows a schematic view of the use of two multi-layer pipes for connecting a hot water heating system to a heat pump.

[0057] In principle, identical parts in the figures are provided with identical reference symbols.

[0058] Ways to implement the invention

[0059] Fig. 1 shows a schematic cross-sectional view through a multi-layer pipeline 1. The multi-layer pipeline 1 has an inner layer 2, an insulation layer 3, and an outer layer 4. The inner layer 2 forms an inner tube, wherein an interior 11 of the inner tube is designed to carry a fluid.

[0060] The inner layer 2 is formed in three layers in Fig. 1 and has a first layer 2', a second layer 2", and a third layer 2"'. The first layer 2' and the third layer 2"' can be formed from the same material, for example a butyl rubber, in particular a chlorobutyl rubber or a bromobutyl rubber; the second layer 2" can form a reinforcing layer and be designed as a textile fabric, in particular comprising nylon fibers, wherein the nylon fibers can be arranged in particular as a nylon fabric. The insulation layer 3 can be designed as a polyurethane foam and / or as an ethylene propylene diene rubber foam (EPDM foam).

[0061] A gap 5 is arranged between the inner layer 2 and the insulation layer 3. This gap 5 is shown ideally in Fig. 1: In general, especially in a laid multi-layer pipeline 1, the distance between the inner layer 2, in particular the third layer 2"' of the inner layer 2, and the insulation layer 3 will not be uniform over the entire angular range as shown in Fig. 1, but will be variable. In particular, gravity can cause a distance between the inner layer 2 and the insulation layer 3 to be smaller in the direction of gravity than in the direction against gravity, since the inner pipe can bend under the influence of gravity.

[0062] The outer diameter 7 of the inner pipe 2 in Fig. 1 is smaller than the inner diameter 6 of the insulation layer 3, with the inner layer 2 and the insulation layer 3 each being designed as a hollow cylinder. This ensures that a gap 5 is always present regardless of the type of bending of the multilayer pipeline 1. The gap 5 can be advantageous when laying the multilayer pipeline 1, as any necessary bending of the multilayer pipeline 1 can be carried out more easily.

[0063] The outer surface 8 of the inner layer 8 can be corrugated. This can provide improved adhesion between the inner pipe and the insulation layer 3 at contact points between the inner layer 2 and the insulation layer 3, which can be caused by bending, thus preventing the inner pipe from slipping. The inner surface 9 of the inner pipe can be smooth in order to better guide a fluid within the interior 11 of the inner pipe. The wall thickness 10 of the insulation layer 3 can be dimensioned such that the desired insulation can be achieved depending on the selected insulation material and a temperature difference between a fluid guided within the interior 11 of the inner pipe and the environment of the multi-layer pipeline 1, for example a temperature in a base pipe.The inner diameter 16 of the inner tube can be dimensioned so that the amount of fluid required for the application can be passed through the inner tube.

[0064] The outer layer 4 is at least partially, preferably completely, non-cohesively connected to the insulation layer 3. The outer layer 4 can be formed as a textile fabric, in particular as a polymer fabric, preferably as a polyamide fabric of the PA 6 type. Thus, the outer layer 4 can be at least partially moved relative to the insulation layer 3, so that the insulation layer 3 can be protected from damage caused by shear forces, which can occur in particular during the installation of the multi-layer pipeline 1. The outer layer 4 is further preferably designed to offer good sliding properties in order to simplify the installation of the multi-layer pipeline, for example, through a base pipe.

[0065] Fig. 2 shows a schematic cross-sectional view through another multi-layer pipeline 1. The multi-layer pipeline 1 has an inner layer 2, an insulation layer 3, and an outer layer 4. The inner layer 2 forms an inner tube, wherein an interior 11 of the inner tube is designed to carry a fluid.

[0066] The inner layer 2 is formed in four layers in Fig. 2 and has a first layer 2', a second layer 2", a third layer 2"', and a fourth layer 2"". The first layer 2' and the third layer 2"' can be formed from the same material, for example a butyl rubber, in particular a chlorobutyl rubber or a bromobutyl rubber; the second layer 2" can form a reinforcing layer and be designed as a textile fabric, in particular comprising nylon fibers, wherein the nylon fibers can be arranged in particular as a nylon fabric. The fourth layer 2"" can be designed as an oxygen barrier layer, in particular as a metallized polyester layer. The insulation layer 3 can be designed as a polyurethane foam and / or as an ethylene propylene diene rubber foam (EPDM foam).

[0067] In Fig. 2, the four layers of the inner layer 2 are arranged as follows, proceeding from the inner surface 9 of the inner tube towards the outer surface 8 of the inner tube: first layer 2', fourth layer 2"", second layer 2" and third layer 2"'. The positions of the fourth layer and the second layer of the four-layer inner layer can also be interchanged, i.e. the four-layer inner layer can have the following layer sequence, proceeding from the inner surface of the inner tube towards the outer surface of the inner tube: first layer, second layer, fourth layer and third layer. A gap 5 is arranged between the inner layer 2 and the insulation layer 3. This gap 5 is shown in Fig.2 is shown in an idealized manner: In general, particularly in a laid multi-layer pipeline 1, the distance between the inner layer 2, in particular the third layer 2"' of the inner layer 2, and the insulation layer 3 will not be uniform over the entire angular range as shown in Fig. 2, but will be variable. In particular, gravity can cause a distance between the inner layer 2 and the insulation layer 3 to be smaller in the direction of gravity than in the direction against gravity, since the inner pipe can bend under the influence of gravity.

[0068] The outer diameter 7 of the inner pipe 2 in Fig. 2 is smaller than the inner diameter 6 of the insulation layer 3, with the inner layer 2 and the insulation layer 3 each being designed as a hollow cylinder. This ensures that a gap 5 is always present regardless of the type of bending of the multilayer pipeline 1. The gap 5 can be advantageous when laying the multilayer pipeline 1, as any necessary bending of the multilayer pipeline 1 can be carried out more easily.

[0069] The outer diameter 7 of the inner tube 2 can be, for example, 37 mm; the inner diameter 16 of the inner tube 2 can be, for example, 25 mm. However, other dimensions are also possible.

[0070] The outer surface 8 of the inner layer 8 can be corrugated. This can provide improved adhesion between the inner pipe and the insulation layer 3 at contact points between the inner layer 2 and the insulation layer 3, which can be caused by bending, thus preventing the inner pipe from slipping. The inner surface 9 of the inner pipe can be smooth in order to better guide a fluid within the interior 11 of the inner pipe. The wall thickness 10 of the insulation layer 3 can be dimensioned such that the desired insulation can be achieved depending on the selected insulation material and a temperature difference between a fluid guided within the interior 11 of the inner pipe and the environment of the multi-layer pipeline 1, for example a temperature in a base pipe.The inner diameter 16 of the inner tube can be dimensioned so that the amount of fluid required for the application can be passed through the inner tube.

[0071] The outer layer 4 is at least partially, preferably completely, non-cohesively connected to the insulation layer 3. The outer layer 4 can be formed as a textile fabric, in particular as a polymer fabric, preferably as a polyamide fabric of the PA 6 type. Thus, the outer layer 4 can be at least partially moved relative to the insulation layer 3, so that the insulation layer 3 can be protected from damage caused by shear forces, which can occur in particular during the installation of the multi-layer pipeline 1. The outer layer 4 is further preferably designed to offer good sliding properties in order to simplify the installation of the multi-layer pipeline, for example, through a base pipe.

[0072] Fig. 3 shows a schematic perspective view of a multilayer pipeline 1, wherein the layer structure shown in Fig. 2 corresponds to that shown in Fig. 1. The multilayer pipeline 1 has an inner layer 2, an insulation layer 3, and an outer layer 4. The multilayer pipeline 1 is designed to carry a fluid in the interior 11 of the inner layer 2.

[0073] Fig. 4 shows a schematic view of a use of two multi-layer pipelines 1', 1" for connecting a hot water heating system 15 to a heat pump 12.

[0074] In order to enable the subsequent installation of a heat pump 12, base pipes 13', 13" can be laid in the ground 14 during the construction of a house, through which pipes can be pulled at a later time to connect the heat pump 12 to the hot water heating system 15. A connection can be made in particular in the basement of a house. Heated water from the heat pump 12 can be led to the hot water heating system 15 through a first pipe 1', and cooled water from the hot water heating system 15 can be led to the heat pump 12 through a second pipe 1". The two multi-layer pipes 1', 1" can be laid in separate base pipes 13', 13" as shown in Fig. 3, or alternatively together in one base pipe.

[0075] Each of the two multi-layer pipelines 1',1" can be guided through the respective base pipe 13',13" as follows: In a first step, a pull-in rope can be attached to one end of a multi-layer pipeline 1',1", and this pull-in rope can be pushed from one end of the base pipe 13',13" to the other end in a second step; in a third step, the multi-layer pipeline 1',1" can be introduced into the base pipe 13',13" by pulling the pull-in rope at this other end and pushing the multi-layer pipeline 1',1" into the base pipe 13',13" towards the other end.Due to the mobility of the outer layer 4 relative to the insulation layer 3, its sliding properties and the gap 5, if present, between the inner layer 2 and the insulation layer 3, laying the multi-layer pipeline 1', 1" through the base pipe 13', 13" can be simplified and carried out without excessive force being required compared to multi-layer pipelines known from the prior art.

[0076] An installer can then connect the multilayer piping 1',1" to the heat pump 12 and the hot water heating system 15 if necessary and, for example, using clamps or other suitable connecting mechanisms.

Claims

Patent claims 1. Multi-layer pipeline (1, 1', 1") for conducting a fluid, wherein the multi-layer pipeline (1, 1', 1") has at least the following layers: a) an inner layer (2, 2', 2", 2'"), which forms an inner pipe for conducting the fluid, b) an insulation layer (3) surrounding the inner layer (2, 2', 2", 2'"), wherein the insulation layer (3) is arranged on a side of the inner layer (2, 2', 2", 2'") facing away from a center line of the inner pipe, c) an outer layer (4) surrounding the insulation layer (3), wherein the outer layer (4) is arranged on a side of the insulation layer (3) facing away from the center line of the inner pipe, and wherein the outer layer (4) is the side adjacent to the insulation layer (3) is not materially connected to the insulation layer (3) and / or is movable relative to the insulation layer (3).

2. Multi-layer pipeline (1.T, 1") according to claim 1, wherein the inner layer (2, 2', 2", 2'") contains rubber, and / or wherein the insulation layer (3) is Polyurethane foam and / or ethylene propylene diene rubber foam (EPDM foam), and / or wherein the outer layer (4) is designed as a textile fabric.

3. Multi-layer pipeline (1, 1', 1") according to claim 2, wherein the textile fabric is formed as a polyamide fabric, in particular comprising polyamides of the type PA 6.

4. Multi-layer pipeline (1, 1', 1") according to one of the preceding claims, wherein the multi-layer pipeline (1, 1', 1") is circular-cylindrical in an unbent state, wherein the inner pipe and the insulation layer (3) are each hollow-cylindrical.

5. Multi-layer pipeline (1, 1', 1") according to one of the preceding claims, wherein the inner layer (2, 2', 2", 2"') is not materially connected to the insulation layer (3) on at least 50%, in particular on at least 70%, in particular on at least 90% and preferably on 100% of its side adjacent to the insulation layer (3).

6. Multi-layer pipeline (1, 1', 1") according to claim 4 and 5, wherein the inner diameter (6) of the insulation layer (3) is between 0.2 to 0.6 cm, preferably 0.4 cm, larger than the outer diameter (7) of the inner pipe, and / or wherein the wall thickness (10) of the insulation layer (3) is between 1.8 to 2.5 cm, preferably 2.2 cm.

7. Multi-layer pipeline (1, 1', 1") according to claim 6, wherein the outer surface (8) of the inner pipe is finely structured, in particular corrugated, and wherein the inner surface (9) of the inner pipe is smooth.

8. Multi-layer pipeline (1, 1', 1") according to claim 6 or 7, wherein the outer diameter (7) of the inner pipe is between 2.3 and 3 cm, preferably 2.5 cm, and / or wherein the inner diameter (16) of the inner pipe is between 1.5 and 1.9 cm, preferably 1.7 cm.

9. Multi-layer pipeline (1, 1', 1") according to one of the preceding claims, wherein the inner layer (2, 2', 2", 2'") is formed in three layers, wherein a first layer (2') of the three-layer inner layer is formed as a butyl rubber layer, wherein a second layer (2") of the three-layer inner layer, which is arranged between the first layer (2') and a third layer (2'") of the three-layer inner layer, is formed as a textile fabric, in particular comprising nylon fibers, and wherein the third layer (2'") is formed as a butyl rubber layer.

10. Multi-layer pipeline (1, 1', 1") according to claim 9, wherein the second layer (2") is formed as a nylon fabric.

11. Multi-layer pipeline (1, 1', 1") according to claim 9 or 10, wherein the first layer (2') is connected to the second layer (2") and the second layer (2") is connected to the third layer (2'") in a materially bonded and / or form-fitting manner.

12. Multi-layer pipeline (1, 1', 1") according to one of claims 1 to 8, wherein the inner layer (2, 2', 2", 2'", 2"") is formed in four layers, wherein a first layer (2') of the four-layer inner layer is formed as a butyl rubber layer, wherein a second layer (2") of the four-layer inner layer, which is arranged between the first layer (2') and a third layer (2'") of the four-layer inner layer, is formed as a textile fabric, in particular comprising nylon fibers, wherein the third layer (2'") is formed as a butyl rubber layer, and wherein a fourth layer (2"") of the four-layer inner layer is arranged between the first layer (2') and the second layer (2"), and the second layer (2") is arranged between the fourth layer (2"") and the third layer (2'"), wherein the fourth layer (2"") is formed as an oxygen barrier layer.

13. Multi-layer pipeline (1, 1', 1") according to claim 12, wherein the fourth layer (2"") is formed as a metallized polyester layer, and / or wherein the second layer (2") is formed as a nylon fabric.

14. Multi-layer pipeline (1, 1', 1") according to claim 11 or 12, wherein the first layer (2') is connected to the fourth layer (2""), the fourth layer (2"") is connected to the second layer (2"), and the second layer (2") is connected to the third layer (2'") in a materially bonded and / or form-fitting manner.

15. Use of a multi-layer pipeline (1, 1', 1") according to one of claims 1 to 14 for connecting a hot water heating system (15) to a heat pump (12).

16. Use of a multi-layer pipeline (1, 1', 1") according to claim 15, wherein the multi-layer pipeline (1, 1', 1") is connected to the heat pump (12) and the Hot water heating system (15) is connected in such a way that it carries water heated by the heat pump (12) to the hot water heating system (15) or that it carries water cooled from the hot water heating system (15) to the heat pump (12), wherein the multi-layer pipeline (1, 1', 1") is laid at least partially in a base pipe (13', 13"), in particular laid in the ground (14).

17. A method for laying a multi-layer pipeline (1, 1', 1") according to one of claims 1 to 14, comprising the step of inserting the multi-layer pipeline (1, 1', 1") through a base pipe (13', 13") previously laid, in particular in the ground (14).

18. The method according to claim 17, wherein the step of inserting the multi-layer pipeline (1,1',1") comprises the following sub-steps: a) force-fitting a pulling rope to a first end of the multi-layer pipeline (1,1',1"); b) pushing the pull-in rope from a first end of the base pipe (13', 13") to the second end of the base pipe (13', 13") until the pull-in rope leaves the base pipe (13', 13") at the second end; and c) pulling on a part of the pull-in rope that has left the base pipe (13', 13") at the second end away from the base pipe (13', 13"), and pushing the multi-layer pipeline (1, 1', 1") into the first end of the base pipe (13', 13") towards the second end until the first end of the multi-layer pipeline (1, 1', 1") leaves the second end of the base pipe (13', 13").

Images