Insulated pipe

Abstract

The present invention provides an insulated pipe comprising one or more inner pipes comprising a plastic, a flexible vacuum insulation panel in the form of units joined to each other wrapped around at least one of the one or more inner pipes, one or more insulation layers, and an outer jacket. The present invention further provides a method and an apparatus for producing the insulated pipe.

Claims

1. An insulated pipe comprising: one or more inner pipes comprising a plastic; a flexible vacuum insulation panel comprising individual vacuum insulation panels joined to each other wrapped around at least one inner pipe of the one or more inner pipes: one or more insulation layers; and an outer jacket, wherein an adhesive or adhesive tape is arranged over at least a seam part of one side of an individual vacuum insulation panel of the individual vacuum insulation panels.

2. The insulated pipe according to claim 1, wherein the insulated pipe comprises two or more inner pipes.

3. The insulated pipe according to claim 2, wherein each inner pipe of the two or more inner pipes is surrounded by the individual vacuum insulation panels.

4. The insulated pipe according to claim 2, wherein only one inner pipe of the two or more inner pipes is surrounded by the individual vacuum insulation panels.

5. The insulated pipe according to claim 1, wherein longitudinal ends of each of the individual vacuum insulation panels are secured together by using at least one of sewing, gluing, laminating and taping.

6. The insulated pipe according to claim 1, wherein a surface of an inner pipe of the one or more inner pipes and the individual vacuum insulation panels are joined together by using the adhesive or adhesive tape.

7. The insulated pipe according to claim 1, further comprising a fastening means comprising plastic film that is wound (i) independently around at least one inner pipe, of the one or more inner pipes, (ii) outside the individual vacuum insulation panels and (iii) inside of the one or more insulation layers, in a form of a helical curve for preventing longitudinal movement of each inner pipe of the one or more inner pipes with respect to the individual vacuum insulation panels.

8. The insulated pipe according to claim 1, wherein the insulated pipe comprises: two or more inner pipes; and a fastening means comprising plastic film that is wound (i) around the two or more inner pipes, (ii) outside the individual vacuum insulation panels and (iii) inside of the one or more insulation layers, in a form of a helical curve and arranged to surround both inner pipes of the two or more inner pipes together for preventing longitudinal movement of the two or more inner pipes with respect to each other.

9. A method for manufacturing an insulated pipe comprising (i) one or more insulation layers, (ii) two or more inner pipes, and (ii) a fastening means comprising plastic film wound (a) around the two or more inner pipes, (b) outside flexible vacuum insulation panels, and (c) inside of the one or more insulation layers in a form of a helical curve, the method comprising: winding the plastic film (i) independently around at least one inner pipe of the two or more inner pipes, (ii) outside the flexible vacuum insulation panels, and (iii) inside of the one or more insulation layers in the form of the helical curve for preventing longitudinal movement of each inner pipe of the one or more inner pipes with respect to the flexible vacuum insulation panels; arranging the one or more insulation layers outside the plastic film and beneath an outer jacket formed outside the one or more insulation layers; and arranging an adhesive or adhesive tape over at least a seam part of one side of an individual vacuum insulation panel of the individual vacuum insulation panels.

10. The method of claim 9, further comprising forming the one or more insulation layers beneath the outer jacket by wrapping an insulation sheet around the one or more inner pipes.

11. An apparatus for manufacturing an insulated pipe, the apparatus comprising: means for feeding longitudinal components, whereby at least one of the longitudinal components is an inner pipe and one of the longitudinal components is a flexible vacuum insulation panel, including individual vacuum insulation panels, which is arranged around the inner pipe; means for arranging one or more foamed insulation layers outside the longitudinal components; an extruder and a corrugator for forming an outer jacket outside the one or more foamed insulation layers; and means for arranging fastening means made up of plastic film in a form of a helical curve to the longitudinal components to touch each of the longitudinal components in such a manner that the fastening means prevent longitudinal movement of the longitudinal components with respect to each other, means for arranging an adhesive or adhesive tape over at least a seam part of one side of an individual vacuum insulation panel of the individual vacuum insulation panels.

12. The apparatus of claim 11, further comprising: a winding device for winding the plastic film in the form of the helical curve (i) independently around the inner pipe, (ii) outside the flexible vacuum insulation panel, and (iii) inside of the one or more foamed insulation layers, in the form of the helical curve for preventing the longitudinal movement of the inner pipe with respect to the flexible vacuum insulation panel, wherein the insulated pipe comprises: two or more inner pipes; and wound plastic film, thus producing a fastening means made up of the plastic film (i) around the two or more inner pipes, (ii) outside the flexible vacuum insulation panel, and (iii) inside of the one or more foamed insulation layers in the form of the helical curve, and wherein the plastic film is arranged to surround two or more of the inner pipes together for preventing the longitudinal movement of the inner pipes with respect to each other.

13. The apparatus of claim 11, further comprising means for arranging a prefabricated insulation layer around the longitudinal components.

14. The apparatus of claim 13, further comprising a wrapping device for wrapping a prefabricated insulation layer around the one or more inner pipe.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) FIG. 1 shows an apparatus for producing an insulated pipe

(2) FIGS. 2A, 2B, 2C and 2D show different views of a piping element.

(3) FIGS. 3A, 3B, 3C and 3D show a vacuum unsulated pipe comprising one inner pipe, wherein a longitudinal end of a web of a VIP is secured.

(4) FIGS. 4A, 4B, 4C and 4D show a vacuum unsulated pipe comprising one inner pipe, wherein the longitudinal ends of the web of VIP are secured in different ways.

(5) FIGS. 5A, 5B, 5C and 5D show a vacuum unsulated pipe comprising one inner pipe, wherein the longitudinal ends of the web of VIP are secured in different ways.

DETAILED DESCRIPTION OF EMBODIMENTS

(6) FIG. 1 shows an apparatus for manufacturing a piping element 10, wherein FIGS. 2A-2D show the individual layers of the piping element 10. The inner pipes 11 are manufactured in advance and wound into coils. The apparatus thus comprises means 1 for feeding the inner pipes 11 from the coils. Specifically, FIG. 2A shows a cutaway drawing of the piping element 10, wherein the piping element is cut through along the centerline. FIG. 2A shows the following individual layers: Inner pipe (11), web of VIP (12), Insulation layers (13, 14), outer jacket (15), wherein a foil 16 wound over the web of VIP is indicated as fat line. FIG. 2B shows a perspective view of the piping element 10, wherein the piping element 10 is cut through at the end and the individual layers (11) to (15) are elongated in a staggered way. The inner pipes 11 are fed through a winding device 3, in which a web of VIP 12 fed from means 2 is wound around the inner pipes 11. In means 4, foil 16 is wound over the web of VIP. Because the inner pipes 11 move continuously forward in the apparatus, i.e. to the left in FIG. 1, and the winding device 4 winds the plastic film roll around the inner pipes 11, the plastic film 16 settles on the web of VIP around the pipes 11 in the form of a helical curve or spiral. The plastic film 16 is wound tightly on the web of VIP 12 and independently around at least one or more of the inner pipes 11 outside the web of VIP 12 and inside of the one or more foamed insulation layers in the form of helical curve for preventing the longitudinal movement of each of the one or more inner pipes 11 with respect to the web of VIP 12 and/or, wherein the insulated pipe 10 comprises two or more inner pipes 11, the plastic film 16 is wound around the two or more inner pipes 11 outside the web of VIP 12 and inside of the one or more foamed insulation layers 13, 14 in the form of helical curve thus arranging the plastic film 16 to surround the two or more inner pipes 11 together for preventing the longitudinal movement of the inner pipes 11 with respect to each other.

(7) The insulating layers 13, 14 are prefabricated insulators in a sheet-like form on a coil 6. From the coil 6, the insulating layers 13, 14 are fed through a wrapping device 6, in which the insulating layers 13, 14 are wrapped around the inner pipes 11. The sides of the insulating layers 13, 14 are joined with a welding device (not shown). The seam formed by the two sides of each of the insulating layers 13, 14 placed against each other is for instance melted closed with hot air in such a manner that the insulating layers 13, 14 completely surround the inner pipes 11. The welding device can also melt the seam closed in some other manner known per se than by utilizing hot air. Instead of the welding device, the sides of the insulating layers 13, 14 can also be joined with a gluing device, for instance.

(8) In addition or alternatively to using a plastic film 16, the web of VIP 12 may be secured to the inner pipe 11. Preferably, this is made by using an adhesive (17) between the inner pipe 11 and the web of VIP (12) (please see FIGS. 2C and 2D) or an adhesive (18, 19) between the longitudinal ends of the web of VIP (please see FIGS. 3C, 3D, 4C, and 4D). FIG. 2C is a vertical sectional view of the piping element 10 showing detail A. FIG. 2D is magnification of detail A showing adhesive (17). It is also possible to use an adhesive tape (20), which can be, for example, applied above the seam outside of the web of VIP (please see FIGS. 5C and 5D).

(9) The inner pipes 11 and the insulating layers 13, 14 wrapped around them are led through the die 8 of an extruder 7. The extruder 7 and die 8 extrude outside the insulating layers 13, 14 a plastic layer, from which the corrugated outer jacket 15 is formed for the insulated pipe 10 in the corrugator 9. The corrugator 9 has two sets of moving chill moulds in a manner known per se. The structure and operation of the extruder 7, die 8 and corrugator 9 are not described in more detail herein, because they are fully known to a person skilled in the art.

(10) As shown in each of FIGS. 2A, 2B, 3A, 3B, 4A, 4B, 5A, and 5B, the insulated pipe 10 has a corrugated outer jacket 15. Inside the outer jacket 15, there are insulating layers 13, 14. Inside the insulating layers 13, 14, there are longitudinal components comprising inner pipe 11 and a web of VIP 12.

(11) The material of the plastic film 16 can be low-density polyethylene PE-LD, for instance, and its thickness 20 μm, for instance. The width of the plastic film 16 can then be 60 to 120 mm, for instance.

(12) In the event of using more than one inner pipe 11 for the insulated pipe 10, the inner pipes 11 may be in the form of a spiral or a helical curve. This winding also in turn helps in that, when the insulated pipe 10 is bent, the inner pipes 11 do not endeavour to move in relation to each other. When manufacturing the insulated pipe 10, the inner pipes 11 can be wound with a separate winding device. Conducted tests show, however, that the inner pipes 11 try to some extent to wind in relation to each other even without any separate winding arrangement. It has been found that this type of self-winding provides a suitable winding in most cases.

(13) The insulating layers 13, 14 may be made of PE, PEX, PP, PUR or aerogel. They are most preferably made of cross-linked closed-cell polyethylene foam. The insulating layers 13, 14 can be formed of one or several prefabricated insulating sheet layers. The thicknesses of the different layers can be the same. Naturally, the width of an outer layer must be greater than that of an inner layer.

(14) The corrugated outer jacket 15 can be made of PE or PP. It is most preferably made of polyethylene PE. Most preferably, the inner pipes 11, insulating layers 13, 14 and outer jacket 15 of the insulated pipe 10 are all made of either cross-linked or conventional polyethylene. For instance, the handling of the insulated pipe 10 during winding is then simple and easy. It is naturally also possible to use other materials. For instance, the insulating layers 13, 14 can also be made of foamed polypropylene. Correspondingly, the outer jacket 15 can also be made of polypropylene.

(15) The outer jacket 15 is preferably corrugated. This enhances the ring stiffness of the insulated pipe 10, for instance 8 to 12 kN/m2. The insulated pipe 10 is especially well suited for underground use. Possible applications are district heating networks and tap water systems, for instance. Due to the optional corrugation, the softness of the insulating layers 13, 14, and the flexibility of the web of VIP, the piping element is bendable. The fact that the insulated pipe 10 is bendable means that the insulated pipe 10 can be coiled for storage and transport and uncoiled for installation. The outer diameter of the insulated pipe 10 can typically be 100 to 300 mm. Piping elements 1 of this kind can be coiled for storage and transport into a coil with a diameter of 0.8 to 3 m, for instance.

(16) The drawing and the related description are intended only to illustrate the idea of the invention. The invention may vary in detail within the scope of the claims. Thus, most preferably, the insulating layer is formed of a prefabricated insulating sheet. The insulator can, however, also be made of a material that is prefabricated into a tube, in which case the tube has a longitudinal slot, through which the longitudinal components, such as inner pipes 11, are installed inside the insulating tube.

(17) The present application further relates to the following items:

(18) Item 1:

(19) An insulated pipe (10) comprising:

(20) one or more inner pipes (11) comprising a plastic

(21) a flexible vacuum insulation panel in the form of units forming a web (12) wrapped around at least one of the one or more inner pipes (11)

(22) one or more insulation layers (13; 14)

(23) an outer jacket (15).

(24) Item 2: The insulated pipe according to one of item 1, wherein the insulated pipe (10) comprises two or more inner pipes (11).

(25) Item 3: The insulated pipe according to item 2, wherein each inner pipe (11) is surrounded by one web of vacuum insulation panels (12).

(26) Item 4: The insulated pipe according to item 2, wherein only one of the inner pipes (11) is surrounded by one web of vacuum insulation panels (12).

(27) Item 5: The insulated pipe according to one of the preceding items, wherein the longitudinal ends of each of the one or more webs of vacuum insulation panels (12) are secured together, preferably by using a method selected from the group consisting of sewing, gluing, laminating, taping, and a combination thereof.

(28) Item 6: The insulated pipe according to one of the preceding items, wherein an adhesive (17, 18, 19) or adhesive tape (20) is arranged over at least the seam part of one side of the web of vacuum insulation panels (12) and the surface of the inner pipe (11) and the web of vacuum insulation panels (12) are joined together by using the (17, 18, 19) or adhesive tape (20).

(29) Item 7: The insulated pipe according to one of the preceding items, further comprising a fastening means made up of plastic film (16) that is wound independently around at least one inner pipe (11) outside the web of flexible vacuum insulation panels (12) and inside of the one or more insulation layers (13, 14) in the form of helical curve for preventing the longitudinal movement of each of the one or more inner pipes (11) with respect to the web of vacuum insulation panels (12).

(30) Item 8: The insulated pipe according to one of the preceding items, wherein the insulated pipe (10) comprises two or more inner pipes and further comprises a fastening means made up of plastic film (16) that is wound around the two or more inner pipes (11) outside the web of flexible vacuum insulation panels (12) and inside of the one or more insulation layers (13, 14) in the form of helical curve and arranged to surround both of the inner pipes together for preventing the longitudinal movement of the inner pipes (11) with respect to each other.

(31) Item 9: A method for manufacturing an insulated pipe according to any one of items 1 to 8, comprising winding plastic film (16), thus producing a fastening means made up of plastic film (16), independently around at least one inner pipe (11) outside the web of flexible vacuum insulation panels (12) and inside of the one or more insulation layers (13, 14) in the form of helical curve for preventing the longitudinal movement of each of the one or more inner pipes with respect to the web of vacuum insulation panels (12) and/or, wherein the insulated pipe comprises two or more inner pipes (11), winding plastic film (16), thus producing a fastening means made up of plastic film (16), around two or more inner pipes (11) outside the web of flexible vacuum insulation panels (12) and inside of the one or more insulation layers (13, 14) in the form of helical curve and arranging plastic film (16) to surround two or more of the inner pipes (11) together for preventing the longitudinal movement of the inner pipes with respect to each other, arranging insulation layers (13, 14) outside the plastic film (16) beneath the outer jacket (15), and forming an outer jacket (15) outside the insulation layers (13, 14).

(32) Item 10: A method as defined in item 9, characterized by forming the one or more insulation layers (13, 14) beneath the outer jacket (15) by wrapping an insulation sheet around the one or more inner pipes (11).

(33) Item 11: An apparatus for manufacturing insulated pipe (10), the apparatus comprising means for feeding longitudinal components, whereby at least one of the longitudinal components is an inner pipe (11) and one of the longitudinal components is a web of flexible vacuum insulation panels (12), which is arranged around one or more of the at least one inner pipe (11), means (6) for arranging one or more foamed insulation layers (13, 14) outside the longitudinal components, an extruder (7) and a corrugator (9) for forming an outer jacket (15) outside the one or more insulation layers (13, 14), and means (5) for arranging fastening means made up of plastic film (16) in the form of helical curve to the longitudinal components to touch each of the longitudinal components in such a manner that the fastening means prevent the longitudinal movement of the longitudinal components with respect to each other.

(34) Item 12: An apparatus as defined in item 11, characterized in that the apparatus comprises a winding device (5) for winding plastic film (16) in the form of a helical curve independently around at least one inner pipe (11) outside the web of flexible vacuum insulation panels (12) and inside of the one or more foamed insulation layers (13, 14) in the form of helical curve for preventing the longitudinal movement of each of the one or more inner pipes (11) with respect to the web of flexible vacuum insulation panels (12) and/or, wherein the insulated pipe (10) comprises two or more inner pipes (11), winding plastic film (16), thus producing a fastening means made up of plastic film (16) around two or more inner pipes (11) outside the web of flexible vacuum insulation panels (12) and inside of the one or more foamed insulation layers (13, 14) in the form of helical curve and arranging plastic film (16) to surround two or more of the inner pipes (11) together for preventing the longitudinal movement of the inner pipes (11) with respect to each other.

(35) Item 13: An apparatus as defined in item 11 or 12, characterized in that the apparatus comprises means (6) for arranging a prefabricated insulation layers (13, 14) around the longitudinal components.

(36) Item 14: An apparatus as defined in item 13, characterized in that the apparatus comprises a wrapping device (6) for wrapping a prefabricated insulation layers (13, 14) around the one or more inner pipes (11).

LIST OF REFERENCE NUMBERS

(37) 1 Inner pipe is fed to the line 2 Web of VIP is fed to the line 3 Web of VIP is wound over the inner pipe 4 The longitudinal ends of the web of VIP are secured together 5 Foil is wound over the web of VIP 6 Insulation layers are fed to the line 7 Extruder plastifies material for outer jacket 8 Die extrudes outer layer 9 Corrugator creates the form of outer layer 10 Insulated pipe 11 Inner pipe 12 Web of VIP 13, 14 Insulation layers 15 Outer jacket 16 Foil 17, 18, 19 Adhesive 20 Adhesive tape