Thermally insulated corrugated pipe outer casing and this comprehensive heat distribution system

Abstract

Thermally insulated corrugated pipe (100), comprising a multi-layered corrugated outer casing (10) for receiving at least one media pipe (50); at least one media tube (50) incorporated in the corrugated outer sheath (10) for guiding a fluid; and at least one insulating layer (60) that at least partially fills the space between the at least one media pipe (50) and the corrugated pipe outer sheath (10); characterized by the fact that The multi-layered corrugated outer casing (10) comprises an inner layer (20); a connecting layer (30) arranged on the inner layer (20) and at least partially connected to the inner layer (20); and a corrugated outer protective layer (40) arranged on the connecting layer (30), the outer layer having corrugated peaks (41, 41') and corrugated troughs (42, 42'). The protective layer (40) is connected to the connecting layer (30) all the way around in the area of ​​the corrugated troughs (42, 42').

Description

[0001] The present invention relates to a thermally insulated corrugated pipe comprising a multilayer corrugated pipe outer casing for accommodating at least one media pipe; at least one media pipe accommodated in the corrugated pipe outer casing for conveying a fluid; and at least one insulation layer that at least partially fills the space between the at least one media pipe and the corrugated pipe outer casing. Furthermore, the present invention relates to a heat distribution system comprising at least one such thermally insulated corrugated pipe.

[0002] Thermally insulated corrugated pipes with a corrugated outer shell are generally known in the state of the art and are used primarily in thermally insulated pipe arrangements, for example, in local and district heating networks. Single-walled, flexible plastic corrugated pipes are available on the market. These can easily be damaged during storage, transport, or careless handling on the construction site, allowing water to penetrate the corrugated pipe from the outside. To counteract this disadvantage, corrugated pipes with a two-layer outer shell are available on the market. These two-layer outer shells incorporate a plastic liner within the corrugated outer layer. Such two-layer outer shells are already less prone to damage on the construction site.However, if damage does occur, allowing water, for example, in the form of rainwater or groundwater, to enter the interior of the corrugated pipe, there is no guarantee that a heat distribution system containing such a corrugated pipe will not partially or completely fill with water and thus become unusable. This can only be remedied with considerable effort and is associated with considerable expense. Particularly high repair costs arise when large amounts of water enter a building uncontrollably through the damaged heat distribution system.

[0003] This is where the present invention comes in. Its objective is to provide a thermally insulated corrugated pipe that at least partially overcomes the disadvantages of the prior art. In particular, the thermally insulated corrugated pipe according to the invention is intended to offer increased protection against water penetration in the event of damage to the outer layer. Furthermore, the bending flexibility of a typical corrugated pipe is intended to be maintained while simultaneously maintaining high annular rigidity. Finally, the present invention also lies in the provision of a heat distribution system comprising at least one such thermally insulated corrugated pipe.

[0004] These and other objects are achieved according to the invention by a thermally insulated corrugated pipe having the features of claim 1 and by a heat distribution system having the features of claim 10. Preferred embodiments of the multilayer corrugated pipe outer casing according to the invention and of the heat distribution system according to the invention are each described in the dependent claims.

[0005] According to the present invention, it was recognized that for a thermally insulated corrugated pipe, a balanced balance of the high flexural flexibility typical of a corrugated pipe and, at the same time, high annular stiffness is achieved when the corrugated pipe outer casing has a three-layer structure, wherein the middle layer is connected to both the inner layer and the corrugated outer protective layer. By connecting the middle layer to the outer protective casing in the region of its corrugation troughs, it is ensured that water that has once passed through the outer protective casing cannot flow further in the longitudinal direction of the multi-layer corrugated pipe outer casing according to the invention. The inner layer is preferably connected over its entire surface to the middle layer, in particular welded or glued, while the outer layer, independently thereof, is preferably connected circumferentially to the middle layer in the region of the corrugated pipe troughs, in particular welded or glued.

[0006] Accordingly, the present invention lies in the provision of a thermally insulated corrugated pipe which comprises a multi-layer corrugated pipe outer shell for receiving at least one media pipe; at least one media pipe received in the corrugated pipe outer shell for conducting a fluid; and at least one insulation layer which at least partially fills the space between the at least one media pipe and the corrugated pipe outer shell; wherein the thermally insulated corrugated pipe is further characterized according to the invention in that the multi-layer corrugated pipe outer shell has an inner layer; a connecting layer arranged on the inner layer and connected to the inner layer at least in sections; and a corrugated outer protective layer arranged on the connecting layer, which has corrugated pipe peaks and corrugated pipe valleys. wherein the protective layer is circumferentially connected to the connecting layer in the region of the corrugated pipe valleys.Furthermore, the present invention provides a heat distribution system comprising at least one thermally insulated corrugated pipe according to the invention.

[0007] With regard to the thermally insulated corrugated pipe according to the invention, it can be advantageous if the wall thickness of the protective layer is greater in the region of the corrugated pipe peaks than in the region of the corrugated pipe valleys. It has been shown that damage to the multi-layer corrugated pipe outer casing caused by continuous high forces can be reduced by a high wall thickness on the outside, i.e. at the corrugated pipe peaks. A smaller wall thickness in the region of the corrugated pipe valleys contributes to high bending flexibility. In preferred embodiments of the multi-layer corrugated pipe outer casing according to the invention, the wall thickness of the protective layer in the region of the corrugated pipe peaks is 10% to 60%, preferably by about 15% to 55%, and particularly preferably by about 20% to 50% greater than in the region of the corrugated pipe valleys.

[0008] It may also prove advantageous within the scope of the present invention if the protective layer between two adjacent corrugated pipe peaks is V-shaped in longitudinal section. This also makes the multi-layer corrugated pipe outer casing of the thermally insulated corrugated pipe according to the invention less susceptible to mechanical damage, for example from larger stones present in the backfill material, which can no longer penetrate deeply into the downwardly tapering V-shaped corrugation troughs. It can be particularly advantageous if the V-shaped design of the protective layer between two adjacent corrugated pipe peaks is rounded towards the connecting layer in the region of the corrugated pipe valleys arranged between the adjacent corrugated pipe peaks. This prevents damage from smaller stones that reach the bottom of the corrugated pipe valleys.On the other hand, this increases the contact area between the V-shaped corrugation troughs and the connecting layer, which contributes to the longitudinal watertightness.

[0009] It can also be advantageous if the protective layer between two adjacent corrugated pipe valleys has a trough-shaped design in longitudinal section. This design ensures that the thick material thickness of the corrugated pipe peaks is present over a large proportion of the pipe jacket length, which also contributes to the damage resistance of the multi-layer corrugated pipe outer jacket. In particularly preferred embodiments of the thermally insulated corrugated pipe according to the invention, the trough-shaped design of the protective layer between two adjacent corrugated pipe valleys has a greater wall thickness in the area of ​​the trough bottom than in the area of ​​the trough walls. As a result, the high wall thickness is concentrated in the areas of the corrugated outer protective layer facing the corrugated pipe outside, which contributes to the high resistance of the corrugated pipe outer jacket to external damage.

[0010] In preferred embodiments of the present invention, the corrugated outer protective layer is formed from or comprises a polymer material. The polymer material is preferably a thermoplastic, in particular a polyolefin. According to the invention, the use of a polyethylene (preferably HDPE, MDPE, or LDPE), a polypropylene, or a cross-linked polyethylene is preferred.

[0011] In a particularly preferred embodiment of the present invention, the corrugated outer protective layer can be made of a cross-linked or uncross-linked polyethylene (PE) or polyethylene copolymers, in an advantageous further development of foamed polyethylene with a density of about 500 kg / m 3exist or contain such a component. In such a case, the corrugated outer protective layer is more robust than an unfoamed protective layer while maintaining comparable flexibility, and it also offers improved thermal insulation.

[0012] It can also be advantageous if the bonding layer is made of or comprises a polymer material. Preferably, the polymer material is a thermoplastic, in particular a polyolefin. According to the invention, the use of a polyethylene (preferably HDPE, MDPE, or LDPE) or a polypropylene is preferred. The bonding layer is particularly preferably designed as a polyethylene film.

[0013] It can also be helpful if the inner layer has a consistent wall thickness over essentially the entire length of the corrugated pipe outer casing. This further increases the damage resistance of the multi-layer corrugated pipe outer casing. Conversely, it can also be helpful if the inner layer has a thinner wall thickness in the area of ​​the corrugated pipe valleys than in the area of ​​the corrugated pipe peaks. A thinner wall thickness of the inner layer in the area of ​​the corrugated pipe valleys contributes to the high bending flexibility of the thermally insulated corrugated pipe according to the invention.

[0014] It is also advantageous if the inner layer is formed from or comprises a polymer material. The polymer material for the inner layer is also a thermoplastic, in particular a polyolefin. According to the invention, the use of a polyethylene, a polypropylene, or a cross-linked polyethylene is preferred. The inner layer is particularly preferably designed as a foam sheet made of foamed polyethylene, in particular foamed cross-linked polyethylene.

[0015] Furthermore, it can be helpful if the at least one insulation layer is a polyurethane foam (PUR foam). This results in a thermally insulated pipe arrangement that is particularly suitable for use in local and district heating networks. The foam can be closed-cell, which alone prevents the further transport of water in the event of damage to the corrugated pipe outer casing according to the invention. The PUR foam preferably has a density (approximately 0.04 to 0.10 kg / l) and a low thermal conductivity (approximately 0.02 to 0.04 W / mK). In this way, the foam achieves good thermal insulation, which can effectively reduce the cooling of the medium to be transported through a thermally insulated corrugated pipe according to the invention.

[0016] In preferred embodiments of the thermally insulated corrugated pipe according to the invention, the at least one media pipe is a pipe made of a polymer material, in particular a thermoplastic, in particular a polyolefin. Particularly preferably, the at least one media pipe is a pipe made of a polypropylene, a polyethylene, or a cross-linked polyethylene, with cross-linked polyethylene pipes being particularly preferred.

[0017] It may also be advantageous if the thermally insulated corrugated pipe according to the invention comprises 2, 3, or 4 media pipes in the corrugated pipe outer casing. This allows a thermally insulated corrugated pipe according to the invention to be adapted to the customer's specifications or the applicable technology. In this way, the transport capacity of such a thermally insulated pipe arrangement can be increased by simultaneously transporting a high fluid volume through several media pipes, and thus also the amount of heat transferred.

[0018] The thermally insulated corrugated pipe according to the invention can comprise at least one barrier layer on or in the protective layer, on or in the at least one insulating layer, or on or in the at least one media pipe, which is intended, in particular, to restrict or prevent the diffusion of oxygen, water vapor, or hydrocarbons. These barrier layers can, in particular, contain polymeric, metallic, or inorganic material.

[0019] The statements relating to the thermally insulated corrugated pipe according to the invention apply accordingly to the heat distribution system according to the invention.

[0020] All plastic materials in the thermally insulated corrugated pipe according to the invention and in the heat distribution system according to the invention can also be used in the form of materials obtained through a recycling process.

[0021] The thermally insulated corrugated pipe according to the invention is preferably produced by a coextrusion process, a post-coextrusion process, or a multi-stage process. Such a coextrusion process for producing the thermally insulated corrugated pipe according to the invention can, in particular, be carried out in several steps. Thus, in a first step, a media pipe can be provided by an extrusion process, which is then encased in an insulating material in a second step. As an insulating material, for example, a thin sheet of a foamed PUR polymer material can be placed around the media pipe and, for example, glued or welded at the abutting edges. In parallel, the corrugated pipe outer jacket can be coextruded. For this purpose, the inner layer with the bonding layer welded to it is passed through an extruder. The protective layer is extruded, and its corrugated shape is created by a corrugator.The insulated carrier pipe can then be inserted into the corrugated pipe outer casing according to the invention. However, other techniques for encasing the carrier pipe with an insulating material are also possible. In particular, it is also possible to create the insulating layer of PUR foam by reacting the components forming the PUR foam directly on the carrier pipe, which has already been inserted into the corrugated pipe outer casing, thus filling the space between the at least one carrier pipe and the corrugated pipe outer casing with the insulating layer during the foaming process.

[0022] The thermally insulated corrugated pipe according to the invention and the heat distribution system according to the invention as well as individual parts thereof can also be manufactured line by line or layer by layer using a line-building or layer-building manufacturing process (e.g. 3D printing), but production by a (co-)extrusion process is preferred.

[0023] In the following, the present invention will be explained in detail with reference to the embodiments shown in the figures. Fig. 1 is a partial longitudinal sectional view of a heat-insulated corrugated pipe of an embodiment of the present invention; and Fig. 2 a partial longitudinal sectional view of a thermally insulated corrugated pipe according to another embodiment of the present invention.

[0024] In the Fig. 1 shows a section of a schematic longitudinal section of a thermally insulated corrugated pipe 100 according to an embodiment of the present invention. According to the Fig. In the embodiment illustrated in Figure 1, the thermally insulated corrugated pipe 100 according to the invention comprises a multi-layer corrugated pipe outer casing 10 for receiving at least one media pipe 100, a media pipe 100 received in the corrugated pipe outer casing 10 for conducting a fluid, and an insulation layer 60 that fills the space between the at least one media pipe 50 and the corrugated pipe outer casing 10. According to this embodiment, the multi-layer corrugated pipe outer casing 10 comprises an inner layer 20; a connecting layer 30 arranged on the inner layer 20 and connected to the inner layer 20 at least in sections; and a corrugated outer protective layer 40 arranged on the connecting layer 30. Due to its corrugated shape, the protective layer 40 has a plurality of corrugated pipe peaks 41, 41' and corrugated pipe valleys 42, 42'.In the embodiment shown, the inner layer 20 is fully welded to the connecting layer 30, while the protective layer 40 is welded all around to the connecting layer 30 in the area of ​​the corrugated tube valleys 42, 42'.

[0025] In the Fig. In the embodiment shown in Figure 1, the protective layer 40 is thicker in the area of ​​the corrugated pipe peaks 41, 41' than in the area of ​​the corrugated pipe troughs 42, 42'. The wall thickness of the protective layer 40 is approximately 50% greater in the area of ​​the corrugated pipe peaks 41, 41' than in the area of ​​the corrugated pipe troughs 42, 42'. Thus, the protective layer 40 is, according to Fig. 1 is approximately 3 mm thick in the area of ​​the corrugated pipe peaks 41, 41', while the wall thickness of the protective layer 40 in the area of ​​the corrugated pipe valleys 42, 42'' is approximately 2 mm. This high wall thickness on the outside reduces the risk of damage to the multi-layer corrugated pipe outer shell 10 due to continuous high forces. In addition, the lower wall thickness in the area of ​​the corrugated pipe valleys 42, 42' contributes to the high bending flexibility of the thermally insulated corrugated pipe 100 according to the invention.

[0026] Between two adjacent corrugated pipe ridges 41, 41', the protective layer 40 is V-shaped in longitudinal section. Larger stones present in the backfill material can thus no longer penetrate deeply into the downwardly tapered V-shaped troughs and damage the protective layer 40. The V-shape of the corrugated pipe troughs 41, 41' is rounded toward the connecting layer. This prevents damage caused by smaller stones reaching the bottom of the corrugated pipe troughs.

[0027] Between two adjacent corrugated pipe valleys 42, 42', the protective layer 40 is trough-shaped in longitudinal section. This trough shape ensures that the thick material thickness of the corrugated pipe peaks 42, 42' is present over a large portion of the pipe jacket length, which further increases the resistance of the multi-layer corrugated pipe outer jacket 10 to external damage. The wall thickness of the protective layer 40 is greater in the area of ​​the trough bottom 411 than in the area of ​​the trough walls 412, 413 adjoining the trough bottom 411.

[0028] According to the Fig. In the embodiment shown in Figure 1, the corrugated outer protective layer 40 is made of high-density polyethylene (HDPE). The connecting layer 30, in the embodiment shown, is a polyethylene film with a thickness of 70 µm.

[0029] In the Fig. In the thermally insulated corrugated pipe 100 shown in Figure 1, the inner layer 20 is designed as a foam board made of foamed cross-linked polyethylene and has a constant wall thickness essentially over the entire length of the corrugated pipe outer sheath 10. The wall thickness of the inner layer 20 is 5 mm.

[0030] According to the Fig. In the embodiment shown in Figure 1, the media tube 50 is formed as a tube made of cross-linked polyethylene (PE-X). It includes a lumen 51 for receiving, storing, or conveying the fluid.

[0031] An insulating layer 60 is arranged on the outer surface of the media pipe 50, with its inner surface in contact with the outer surface of the media pipe 50. The insulating layer 60 is formed as a layer of polyurethane. The insulating layer 60 was produced directly on the media pipe 50 by a polymerization reaction of the polyurethane-forming components, resulting in foaming. Alternatively, the insulating layer 60 can also be formed as a thin sheet of polyurethane foam, which is wrapped around the media pipe 50 and bonded or welded at its abutting edges in the axial and radial directions.

[0032] In Fig. 2 shows a further embodiment of the thermally insulated corrugated pipe 100 according to the invention. To avoid repetition, only differences to the Fig. 1 illustrated embodiment of the thermally insulated corrugated pipe 100 according to the invention. The embodiments of Fig. 1 also apply to the embodiment according to Fig. 2 accordingly. Identical elements are indicated in the illustrations by identical reference symbols.

[0033] In Fig. 2 shows a further embodiment of the thermally insulated corrugated pipe 100 according to the invention in a schematic partial longitudinal section. Fig. The embodiment shown in section 2 differs from the one shown in section 2. Fig. 1 only with regard to the distribution of the wall thickness of the inner layer 30 in the longitudinal direction of the corrugated pipe outer casing 10. The inner layer 20 has a wall thickness approximately one-third lower in the region of the corrugated pipe valleys 42, 42' than in the region of the corrugated pipe peaks 41, 41'. The lower wall thickness of the inner layer 20 in the region of the corrugated pipe valleys 41, 41' further improves the high bending flexibility of the thermally insulated corrugated pipe 100 according to the invention.

[0034] It is understood that the features explained above can be used not only in the combination specified in each case, but also in other combinations or on their own, without departing from the scope of the present invention.

[0035] The present invention has been explained in detail by way of example with reference to the embodiments illustrated in the figures. It is to be understood that the present invention is not limited to these embodiments. Rather, the scope of the present invention is determined by the appended claims.

Claims

[1] Thermally insulated corrugated pipe (100), comprising a multi-layer corrugated pipe outer jacket (10) for receiving at least one media pipe (50); at least one media pipe (50) accommodated in the corrugated pipe outer casing (10) for guiding a fluid; and at least one insulation layer (60) which at least partially fills the space between the at least one media pipe (50) and the corrugated pipe outer casing (10); characterized by , that The multi-layer corrugated pipe outer casing (10) comprises an inner layer (20); a connecting layer (30) arranged on the inner layer (20) and connected to the inner layer (20) at least in sections; and a corrugated outer protective layer (40) arranged on the connecting layer (30) and having corrugated pipe peaks (41, 41') and corrugated pipe valleys (42, 42'). The protective layer (40) is connected circumferentially to the connecting layer (30) in the region of the corrugated pipe valleys (42, 42'). [2] Thermally insulated corrugated pipe (100) according to claim 1, characterized by that the wall thickness of the protective layer (40) is greater in the area of the corrugated pipe peaks (41, 41') than in the area of the corrugated pipe valleys (42, 42'). [3] Thermally insulated corrugated pipe (100) according to one of claims 1 or 2, characterized by that the protective layer (40) between two adjacent corrugated pipe mountains (41, 41') is V-shaped in longitudinal section. [4] Thermally insulated corrugated pipe (100) according to claim 3, characterized by that the V-shaped configuration of the protective layer (40) between two adjacent corrugated pipe peaks (41, 41') is rounded towards the connecting layer (30) in the region of the corrugated pipe valleys (42) arranged between the adjacent corrugated pipe peaks (41, 41'). [5] Thermally insulated corrugated pipe (100) according to one of claims 1 to 4, characterized by that the protective layer (40) between two adjacent corrugated pipe valleys (42, 42') is trough-shaped in longitudinal section. [6] Thermally insulated corrugated pipe (100) according to claim 5, characterized by that the trough-shaped design of the protective layer (40) between two adjacent corrugated pipe valleys (42, 42') has a greater wall thickness in the area of the trough bottom (411) than in the area of the trough walls (412, 413). [7] Thermally insulated corrugated pipe (100) according to one of claims 1 to 6, characterized by that the inner layer (20) has a constant wall thickness substantially over the entire length of the corrugated pipe outer casing (10). [8] Thermally insulated corrugated pipe (100) according to one of claims 1 to 7, characterized by that the inner layer (20) has a smaller wall thickness in the region of the corrugated pipe valleys (42, 42') than in the region of the corrugated pipe peaks (41, 41'). [9] Thermally insulated corrugated pipe (100) according to one of claims 1 to 8, characterized bythat the connection of the inner layer (20) to the connecting layer (30) and the connection of the connecting layer (30) to the protective layer (40) are designed independently of one another as welding and / or gluing. [10] Heat distribution system comprising at least one thermally insulated corrugated pipe (100) according to one of claims 1 to 9.

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