WO2015143289A1

WO2015143289A1 - Piping system

Info

Publication number: WO2015143289A1
Application number: PCT/US2015/021695
Authority: WO
Inventors: Hans Van Den Bergh; Dirk K. M. TOTTE; Abboud L. Mamish
Original assignee: Berry Plastics Corporation
Priority date: 2014-03-21
Filing date: 2015-03-20
Publication date: 2015-09-24

Abstract

A piping system includes two pipes joined at a pipe joint. A covering is applied to exterior surfaces of both pipes to cover the pipe joint defined between the two pipes.

Description

PIPING SYSTEM

PRIORITY CLAIM

[0001] This application claims priority under 35 U.S.C. § 119(e) to US

Provisional Application Serial No. 61/968,589, filed March 21, 2014, which is expressly incorporated by reference herein.

BACKGROUND

[0002] The present disclosure relates to piping systems. More particularly, the present disclosure relates to sleeves for covering pipe joints formed in pipelines.

SUMMARY

[0003] A conduit in accordance with the present disclosure includes a tube including at least two pipes joined to one another in end-to-end relation at a pipe joint and a sleeve coupled to the tube to cover and protect the pipe joint. The sleeve includes a wraparound sheet that is wrapped around the pipe joint after the pipe joint has been formed.

[0004] In illustrative embodiments, the wraparound sheet is wrapped around the pipe joint of the tube and formed to include a heat-conducting moisture barrier layer to provide means for protecting the pipe joint from damage, transferring heat through the wraparound sheet to an adhesive layer to seal the pipe joint, and providing a diffusion barrier between the pipe joint and an environment surrounding the tube. In illustrative embodiments, the heat-conducting moisture barrier layer comprises aluminum.

[0005] In illustrative embodiments, the wraparound sheet includes in series, the heat-conducting moisture barrier layer, a foundation-adhesive layer, a barrier- foundation layer, and the adhesive layer. The foundation-adhesive layer couples the barrier layer to the barrier-foundation layer. The barrier-foundation layer provides support to the heat-conducting moisture barrier layer. The adhesive layer couples the wraparound sheet to exterior layers applied to the two pipes that cooperate to form the tube and seals the pipe joint defined between the two pipes.

[0006] In illustrative embodiments, the sleeve also includes a foam insulator covering the pipe joint. In one embodiment, two pre-molded inserts are mated to define the foam insulator. In another embodiment, the foam insulator is molded in place on exposed portions of the two pipes defining the pipe joint. The adhesive layer of the wraparound sheet is coupled to the foam insulator and to adhesive strips also included in the sleeve and coupled to pipe jackets formed to include the exterior layers associated with the two pipes.

[0007] Additional features of the present disclosure will become apparent to those skilled in the art upon consideration of illustrative embodiments exemplifying the best mode of carrying out the disclosure as presently perceived.

BRIEF DESCRIPTIONS OF THE DRAWINGS

[0008] The detailed description particularly refers to the accompanying figures in which:

[0009] Fig. 1 is an exploded assembly view of a first embodiment of a conduit in accordance with the present disclosure showing that the conduit includes, from bottom to top, a tube and a sleeve for covering a pipe joint formed between two fluid- transport units included in the tube, that the sleeve includes, from left to right, a first adhesive strip, a pair of foam-insulation inserts cooperating to form a foam insulator, a wraparound sheet, a second adhesive strip, and an heat- activated heat-shrinkable casing, and suggesting that the wraparound sheet includes a heat-conducting moisture barrier layer;

[0010] Fig. 2 is a diagrammatic view of the conduit showing that the conduit includes a tube comprising a first fluid-transport unit including a first pipe and a first multilayer pipe jacket on an exterior portion of the first pipe and an adjacent second fluid-transport unit including a second pipe that is aligned in end-to-end relation with the first pipe to establish a pipe joint therebetween and a second multilayer pipe jacket on an exterior portion of the second pipe and showing that the conduit also includes a sleeve comprising a foam insulator around the pipe joint, a first adhesive strip mating with the first multiplayer pipe jacket associated with the first pipe, a second adhesive strip mating with the second multilayer pipe jacket associated with the second pipe, a cold-applied wraparound sheet covering the foam insulator, and a heat- activated heat shrinkable casing covering the wraparound sheet and the adhesive strips, and suggesting that the wraparound sheet includes a heat-conducting moisture barrier layer, a foundation-adhesive layer, a barrier-foundation layer, and a foam-adhesive layer; [0011] Figs. 3 and 4 provide a series of views showing formation of the pipe joint between a first pipe included in the first fluid- transport unit and a second pipe included in the second fluid-transport unit before the sleeve is applied to the tube to cover and protect the pipe joint as suggested in Figs. 5-9;

[0012] Fig. 3 is a perspective view of the conduit suggesting that the heat- activated heat-shrinkable casing included in the sleeve is positioned around the second fluid-transport unit and then the first and second pipes are brought together so that ends of each pipe are arranged to abut one another to form a pipe joint shown in Fig. 4 and showing that each fluid- transport unit includes one of the pipes and a pipe jacket covering the pipe and including, from inside to outside, an insulation layer, an aluminum layer, and a pipe coating layer;

[0013] Fig. 4 is a view similar to Fig. 3 showing that, prior to welding, portions of the pipe jacket of each fluid-transport unit are removed to expose the end of each pipe so that the pipe jacket is not damaged by heat during welding and that the pipe joint is formed between the ends of the pipes to join the two pipes together and suggesting that the pair of foam-insulation inserts included in the sleeve are coupled around the exposed ends of the pipes after the heat pipes have cooled sufficiently;

[0014] Figs. 5-9 provide a series of views showing application of the sleeve to the tube to establish the conduit;

[0015] Fig. 5 is a perspective view showing the pipe joint of the tube covered by the pair of foam-insulation inserts and the heat-activated heat shrinkable casing positioned to surround a portion of the second pipe to lie in spaced-apart relation to the pipe joint and suggesting that the wraparound sheet is aligned with the (hidden) pipe joint and then wrapped around the foam-insulation inserts and the pipe jackets of the first and second fluid- transport units to cover and protect the pipe joint;

[0016] Fig. 6 is a view similar to Fig. 5 showing the wraparound sheet wrapped around the pair of foam- insulation inserts and the pipe jackets of the first and second fluid- transport units to protect the pipe joint, suggesting that the first adhesive strip is aligned on a first side of the wraparound sheet to be wrapped around the first fluid- transport unit as suggested in Fig. 7 and the second adhesive strip is aligned on a second side of the wraparound sheet to be wrapped around the second fluid-transport unit, and suggesting that release liners included in the first and second adhesive strips are removed prior to the adhesive strips being wrapped around the pipe jackets of the first and second fluid-transport units such that an inner and outer adhesive layer included in each adhesive strip is exposed;

[0017] Fig. 7 is a view similar to Fig. 6 showing that adhesive strips have been wrapped around the pipe jackets adjacent to the wraparound sheet such that the inner adhesive layers engage the pipe jackets of each fluid-transport unit and that the release liners have been partially removed to expose the outer adhesive layer of the first and second adhesive strips;

[0018] Fig. 8 is a view similar to Fig. 7 showing that the heat- activated heat- shrinkable casing has been slid laterally along the length of the tube over the wraparound sheet and pipe joint to cover the first adhesive strip, the wraparound sheet, and the second adhesive strip;

[0019] Fig. 9 is a view similar to Fig. 8 showing use of a torch to apply heat to all exterior surfaces of the heat- activated heat-shrinkable casing to cause the heat- activated heat-shrinkable casing to shrink so that the adhesive layers of the adhesive strips bond to the pipe jackets and heat-activated heat-shrinkable casing and the adhesive layer of the wraparound sheet to activate and seal the pipes at the pipe joint due to the pressure of the heat- activated heat-shrinkable casing shrinking;

[0020] Fig. 10 is a diagrammatic sectional view of the wraparound sheet showing that the wraparound sheet includes, from top to bottom, the heat-conducting moisture barrier layer, the foundation-adhesive layer, the barrier-foundation layer, and the foam-adhesive layer;

[0021] Fig. 11 is a diagrammatic sectional view of the conduit showing the tube and sleeve before the heat- activated heat-shrinkable casing has been positioned over the pipe joint;

[0022] Fig. 12 is a diagrammatic sectional view similar to Fig. 11 showing the conduit after the heat- activated heat-shrinkable casing has been positioned over the pipe joint to cover the adhesive strips and the wraparound sheet and heat has been applied to the heat- activated heat-shrinkable casing to shrink the heat-activated heat- shrinkable casing;

[0023] Fig. 13 is an exploded assembly view of a second embodiment of a conduit in accordance with the present disclosure showing that the conduit includes, from bottom to top, a tube and a sleeve for covering a pipe joint formed between two fluid- transport units included the tube, that the sleeve includes, from left to right, a first adhesive strip, a foam insulator (shown in phantom) that is foamed in-place around the pipe joint, a wraparound sheet, a second adhesive strip, and a heat- activated heat-shrinkable casing, and suggesting that the wraparound sheet includes a heat-conducting moisture barrier layer;

[0024] Figs. 14-15 provide a series of views showing formation of the pipe joint between a first pipe included in the first fluid- transport unit and a second pipe included in the second fluid-transport unit before the sleeve is applied to the tube to cover and protect the pipe joint as suggested in Figs. 16-23;

[0025] Fig. 14 is a perspective view of the conduit suggesting that the heat- activated heat-shrinkable casing included in the sleeve is positioned around the second fluid-transport unit and then the first and second pipes are brought together so that ends of each pipe are arranged to abut one another to form a pipe joint shown in Fig. 15 and showing that each fluid- transport units includes one of the pipes and a pipe jacket covering the pipe and including, from inside to outside, an insulation layer, and a pipe coating layer;

[0026] Fig. 15 is a view similar to Fig. 14 showing that portions of the pipe jacket of each fluid-transport unit are stripped away prior to welding to expose an end of each pipe so that the pipe jacket is not damaged by heat during the welding and that the ends of the pipes are welded to join the two pipes together;

[0027] Figs. 16-18 are a series of views showing an illustrative process of molding a foam insulator in-place around the tube to cover the pipe joint and extend between the pipe jackets of the first fluid- transport unit and the second fluid-transport unit after the portions of the pipe defining the pipe joint have been welded and then cooled sufficiently;

[0028] Fig. 16 is a diagrammatic view of the tube after the pipe joint has been established but before the sleeve has been applied to the tube and showing that an insulation unit mold has been positioned around the tube to cover the pipe joint and the pipe jackets of the first and second fluid transport units and a foam applicator has been coupled to the insulation unit mold to supply liquid foaming material to a mold cavity formed between the insulation mold unit and the tube;

[0029] Fig. 17 is a view similar to Fig. 16 showing that liquid foaming material has been delivered into the mold cavity by the foam applicator to form the foam insulator around the pipe joint and the insulation unit mold is maintained in position around the pipe joint while the liquid foaming material expands and solidifies;

[0030] Fig. 18 is a view similar to Fig. 17 showing that the foam insulator is established after the liquid foaming material has expanded and solidified and the insulation unit mold has been removed;

[0031] Figs. 19-23 provide a series of views showing application of the sleeve to the tube to establish the conduit of Fig. 13;

[0032] Fig. 19 is a perspective view showing the pipe joint of the tube covered by the foam insulator and the heat-activated heat shrinkable casing positioned to surround a portion of the second pipe to lie in spaced-apart relation to the pipe joint and suggesting that the wraparound sheet is aligned with the (hidden) pipe joint and then wrapped around the foam insulator and the pipe jackets of the first and second fluid- transport units to cover and protect the pipe joint;

[0033] Fig. 20 is a view similar to Fig. 19 showing the wraparound sheet wrapped around the foam insulator and the pipe jackets of the first and second fluid- transport units to protect the pipe joint, suggesting that the first adhesive strip is aligned on a first side of the wraparound sheet to be wrapped around the first fluid- transport unit as suggested in Fig. 21 and the second adhesive strip is aligned on a second side of the wraparound sheet to be wrapped around the second fluid-transport unit, and suggesting that release liners included in the first and second adhesive strips are removed prior to the adhesive strips being wrapped around the pipe jackets of the first and second fluid-transport units such that an inner and outer adhesive layer included in each adhesive strip is exposed;

[0034] Fig. 21 is a view similar to Fig. 20 showing that adhesive strips have been wrapped around the pipe jackets adjacent to the wraparound sheet such that the inner adhesive layers engage the pipe jackets of each fluid- transport unit and that the release liners have been partially removed to expose the outer adhesive layer of the first and second adhesive strips;

[0035] Fig. 22 is a view similar to Fig. 21 showing that the heat- activated heat- shrinkable casing has been slid laterally along the tube over the wraparound sheet and pipe joint to cover the first adhesive strip, the wraparound sheet, and the second adhesive strip; [0036] Fig. 23 is a view similar to Fig. 22 showing use of a torch to apply heat to all exterior surfaces of the heat-activated heat-shrinkable casing to cause the heat- activated heat-shrinkable casing to shrink so that the adhesive layers of the adhesive strips bond to the pipe jackets and heat-activated heat-shrinkable casing and the adhesive layer of the wraparound sheet to activate and seal the pipes at the pipe joint due to the pressure of the heat- activated heat-shrinkable casing shrinking;

[0037] Fig. 24 is a diagrammatic sectional view of the wraparound sheet showing that the wraparound sheet includes, from top to bottom, the barrier layer and the adhesive layer;

[0038] Fig. 25 is a diagrammatic sectional view of the piping system of Fig. 1 showing the tube and sleeve before the heat- activated heat-shrinkable casing has been positioned over the pipe joint;

[0039] Fig. 26 is a diagrammatic sectional view similar to Fig. 25 showing the conduit after the heat- activated heat-shrinkable casing has been positioned over the pipe joint to cover the adhesive strips and the wraparound sheet and heat has been applied to the heat- activated heat-shrinkable casing to shrink the heat-activated heat- shrinkable casing; and

[0040] Fig. 27 is a diagrammatic view of the conduit showing that the conduit includes a tube and a sleeve, the tube includes the first and second fluid-transport units that each include the pipe, the insulation layer, and the pipe coating layer, and the sleeve includes the foam insulator formed around the pipe joint, the wraparound sheet coupled to the pipe jackets of the first and second fluid- transport units, the adhesive strips coupled to the pipe jackets, and the heat- activated heat-shrinkable casing positioned around the pipe joint to cover the adhesive strips and wraparound sheet and coupled to the adhesive strips.

DETAILED DESCRIPTION

[0041] A first embodiment of a conduit 10 in accordance with the present disclosure is shown in Figs. 1-12. A second embodiment of a conduit 110 in accordance with the present disclosure is shown in Figs. 13-27.

[0042] Conduit 10, as shown for example in Fig. 1, includes a tube 12 comprising first and second pipes 40, 44 mated in end-to-end relation to establish a pipe joint 18 therebetween and a sleeve 14 coupled to tube 12 to cover pipe joint 18. Sleeve 14 includes a wraparound sheet 16 arranged to be wrapped around tube 12. Wraparound sheet 16 includes a heat-conducting moisture barrier layer 32 and is configured to provide a means for protecting pipe joint 18 from damage, transferring heat through wraparound sheet 16 during installation, and providing a diffusion barrier between pipe joint 18 and an environment surrounding tube 12 as suggested in Figs. 1 and 2. In some embodiments, heat-conducting moisture barrier layer 32 comprises aluminum. In other embodiments, heat-conducting moisture barrier layer 32 comprises copper or any other suitable heat-conducting material.

[0043] Tube 12 includes a number of groups of first and second pipes 40, 44 connected end-to-end for long distance fluid transport. As an example, tube 12 may be used to transport heated water from a cogeneration plant to residential or commercial customers as part of a district heating system. In illustrative

embodiments, pipes 40, 44 are covered by companion pipe jackets 42, 46 to insulate and protect pipes 40, 44. Pipe jackets 42, 46 are removed at ends 56, 58 of each pipe 40, 44 of tube 12 where pipe joint 18 is to be established as suggested in Fig. 1. After pipe joint 18 is established, sleeve 14 covers exposed pipe joint 18 to insulate and protect tube 12 at pipe joint 18 as suggested in Figs. 1 and 6.

[0044] Sleeve 14 includes a heat- activated heat-shrinkable casing 30 formed to include a tube-receiving passageway 30P, a foam insulator 26 positioned to lie in the tube-receiving passageway 30P and adapted to mate with and surround portions of first and second pipes 20, 22 that cooperate to form a tube 12 and to cover a pipe joint 18 formed between the first and second pipes 20, 22, and a cold- applied tubular wraparound sheet 16 arranged to lie in the tube-receiving passageway 30P formed by heat-activated heat-shrinkable casing 30 and formed to include an insulator-receiving passageway 16P as suggested in Figs. 1, 2, and 6. Foam insulator 26 is located in the insulator-receiving passageway 16P formed in the cold- applied tubular wraparound sheet 16 as suggested in Fig. 6.

[0045] The cold- applied tubular wraparound sheet 16 includes a foam- adhesive layer 38 mating with an exterior portion of foam insulator 26 and a heat- conducting moisture barrier layer 32 interposed between foam-adhesive layer 38 and heat-activated heat-shrinkable casing 30 as suggested in Fig. 2. The heat-conducting moisture barrier layer 32 is configured to provide means for transferring heat (H) applied to heat-activated heat-shrinkable casing 30 to foam- adhesive layer 38 and for blocking flow of liquid accumulating in a space provided between an interior surface of heat- activated heat-shrinkable casing 30 and an exterior surface of the cold-applied tubular wraparound sheet 16 to foam-adhesive layer 38 and to foam insulator 26.

[0046] The cold- applied tubular wraparound sheet 16 further includes a barrier-foundation layer 36 and a foundation-adhesive layer 34 as suggested in Fig. 2. Barrier-foundation layer 36 is interposed between the heat-conducting moisture barrier layer 32 and foam-adhesive layer 38 and arranged to mate with foam-adhesive layer 38. Foundation-adhesive layer 34 is arranged to interconnect the heat- conducting moisture barrier layer 32 and the barrier-foundation layer 36. Foundation- adhesive layer 34, barrier-foundation layer 36, and foam-adhesive layer 38 cooperate to provide means for transferring heat (H) discharged from the heat-conducting moisture barrier layer 38 to foam insulator 26 and to adhesive strips 24, 28 as suggested diagrammatically in Fig. 2. The heat-conducting moisture barrier layer 32 comprises aluminum in an illustrative embodiment.

[0047] Tube 12 includes first and second fluid-transport units 20, 22 as suggested in Figs. 1 and 2. First fluid- transport unit 20 comprises a first pipe 40 and a first pipe jacket 42 on the first pipe 40. Second fluid- transport unit 22 comprises a second pipe 44 and a second pipe jacket 46 on the second pipe 44.

[0048] Second pipe jacket 46 is arranged to lie in spaced-apart relation to first pipe jacket 42 to locate foam insulator 26 therebetween as suggested in Figs. 1, 2, and 6. A first-end portion of the foam-adhesive layer 38 mates with first pipe jacket 42 associated with first pipe 40 to transfer heat (H) discharged from heat-conducting moisture barrier layer 32 to first pipe jacket 42 as suggested diagrammatically in Fig. 2. An opposite second-end portion of foam-adhesive layer 38 mates with second pipe jacket 46 associated with second pipe 44 to transfer heat (H) discharged from heat-conducting moisture barrier layer 38 to second pipe jacket 46 as suggested diagrammatically in Fig. 2. A middle portion of foam-adhesive layer 38 is interposed between the first-end and second-end portions and is mated with the exterior portion of foam insulator 26 as suggested diagrammatically in Fig. 2 to transfer heat (H) discharged from heat-conducting moisture barrier layer 38 to foam insulator 26.

[0049] First pipe jacket 42 of first fluid- transport unit 20 is arranged to mate with and surround an exterior portion of first pipe 40 as suggested in Figs. 1 and 2. Second pipe jacket 46 is arranged to mate with and surround an exterior portion of second pipe 44. Foam insulator 26 is arranged to mate with and surround exterior portions of each of the first and second pipe 40, 44 and to cover the pipe joint 18 defined between the first and second pipes 40, 44. First pipe jacket 42 is configured to provide means for blocking ingress of water from the surroundings to first pipe 40. Second pipe jacket 46 is configured to provide means for blocking ingress of water from the surroundings to second pipe 44.

[0050] Sleeve 14 further includes first and second adhesive strips 24, 28 as suggested in Figs. 1 and 2. First adhesive strip 24 is interposed between and mated with each of the first pipe jacket 42 and a first portion of the heat- activated heat- shrinkable casing 30. Second adhesive strip 28 is interposed between and mated with each of the second pipe jacket 46 and a second portion of the heat- activated heat- shrinkable casing 30. The cold-applied tubular wraparound sheet 16 is arranged to lie on foam insulator 26 in a position between the first and second adhesive strips 24, 28. The heat-conducting moisture barrier layer 32 is positioned to lie between the first and second adhesive strips 24, 28.

[0051] The heat-conducting moisture barrier layer 38 is configured to provide means for blocking diffusion of a blowing agent gas included in liquid foaming material provided to form the foam insulator 26 to the surrounding environment as the liquid foaming material solidifies during completion of formation of the foam insulator 26 on the first and second pipes 40, 44 to maximize cell size in the foam insulator 26 and enhance thermal insulation properties of the cold-applied tubular wraparound sheet 16. The heat-conducting moisture barrier layer 38 comprises aluminum in an illustrative embodiment.

[0052] Sleeve 14 includes a first adhesive strip 24, a foam insulator 26 comprising a pair of foam- insulation inserts, wraparound sheet 16, a second adhesive strip 28, and a heat-activated heat- shrinkable casing 30 as shown in Fig. 1. To apply sleeve 14 to tube 12, a foam insulator 26 comprising a pair of foam-insulation inserts is positioned around pipe joint 18 as shown in Fig. 5. Wraparound sheet 16 is then wrapped around the foam-insulation inserts included in foam insulator 26 and pipe jackets 42, 46 as shown in Fig. 6. First adhesive strip 24 is wrapped around a first pipe jacket 42 adjacent to wraparound sheet 16 as shown in Fig. 7. Second adhesive strip 28 is wrapped around a second pipe jacket 46 adjacent to wraparound sheet 16 as shown in Fig. 7. Heat-activated heat- shrinkable casing 30 is positioned over wraparound sheet 16 and adhesive strips 24, 28 as shown in Fig. 8. Exterior surfaces of heat- activated heat-shrinkable casing 30 are then heated with a torch to shrink heat- activated heat-shrinkable casing 30 around wraparound sheet 16 and adhesive strips 24, 28 and activate an adhesive layer 38 included in wraparound sheet 16 and adhesive strips 24, 28 to seal the pipes 40, 44 establishing pipe joint 18 and couple sleeve 14 to tube 12 as shown in Fig. 9.

[0053] Conduit 10 includes tube 12 and sleeve 14 for covering tube 12 as shown in Fig. 1. Tube 12 is formed to include a first fluid-transport unit 20, a second- fluid transport unit 22, and a pipe joint 18 lying between first fluid-transport unit 20 to second- fluid transport unit 22 as shown in Figs. 1, 3, and 12. First and second fluid- transport units 20, 22 are configured to receive a fluid and transport the fluid a length of fluid-transport units 20, 22. First and second fluid-transport units 20, 22 are joined end-to-end to increase the length of travel that the fluid is transported. In illustrative embodiments, ends 56, 58 of pipes 40, 44 are welded together at pipe joint 18.

[0054] In the illustrative embodiment, tube 12 is depicted as including first and second fluid-transport units 20, 22. In other embodiments, tube 12 includes a number of fluid transport units joined end-to-end.

[0055] First fluid- transport unit 20 includes first pipe 40 and first pipe jacket

42 covering a length of first pipe 40 as shown in Fig. 1. Second fluid-transport unit 22 includes second pipe 44 and second pipe jacket 46 covering a length of second pipe 44. First and second pipes 40, 44 are configured to receive the fluid and transport the fluid the length of pipes 40, 44. First and second pipes 40, 44 comprise steel in an illustrative embodiment. In other embodiments, first and second pipes 40, 44 may comprise materials such as, for example, copper, iron, aluminum,

polyethylene, or polyvinyl chloride. In some embodiments, first and second pipes 40, 44 include a surface treatment such as, for example, an epoxy or a polymeric coating.

[0056] First pipe jacket 42 covers first pipe 40 to insulate and protect first pipe

40 as shown in Figs. 1 and 2. First pipe jacket 42 includes an insulation layer 50, an aluminum layer 52, and a pipe coating layer 54. Second pipe jacket 46 covers second pipe 44 to insulate and protect second pipe 44. Second pipe jacket 46 includes an insulation layer 60, an aluminum layer 62, and a pipe coating layer 64.

[0057] Insulation layers 50, 60 cover pipes 40, 44 to insulate pipes 40, 44 and block heat transfer between pipes 40, 44 and the environment surrounding tube 12 as shown in Figs. 1 and 2. Insulation layers 50, 60 comprise polyurethane in the illustrative embodiment.

[0058] Aluminum layers 52, 62 cover insulation layers 50, 60 to provide a barrier layer as shown in Figs. 1 and 2. In the illustrative embodiment, aluminum layers 52, 62 provide diffusion barrier means for blocking diffusion of a gas used as a blowing agent when forming insulation layers 50, 60 so that a more complete insulation forming process is provided as compared with processes with no aluminum layers. The more complete insulation process forms insulation layers 50, 60 with improved thermal insulation properties.

[0059] Pipe coating layers 54, 64 cover aluminum layers 52, 62 to protect aluminum layers 52, 62 and insulation layers 50, 60 from damage as shown in Figs. 1 and 2. For example, pipe coating layers 54, 64 block damage such as, for example, inadvertent piercing of insulation layers 50, 60 and aluminum layers 52, 62. Pipe coating layers 54, 64 block water ingress from the environment into the tube 12, and thus, block corrosion of pipes 40, 44. Pipe coating layers 54, 64 comprise high- density polyethylene in an illustrative embodiment.

[0060] Sleeve 14 is applied to tube 12 to cover and protect pipe joint 18 as suggested in Figs. 1-9. Sleeve 14 includes first adhesive strip 24, foam-insulation inserts 26, wraparound sheet 16, second adhesive strip 28, and heat- activated heat- shrinkable casing 30 as shown in Figs. 1 and 2. A foam insulator 26 comprising foam- insulation inserts provides thermal insulation between pipe joint 18 and the environment. Wraparound sheet 16 seals pipe joint 18 to block water ingress into foam insulator 26 and tube 12. Adhesive strips 24, 28 and heat- activated heat- shrinkable casing 30 provide a secondary seal around wraparound sheet 16 and pipe joint 18.

[0061] The foam-insulation inserts of foam insulator 26 cover exposed pipe ends 56, 58 and pipe joint 18 to insulate pipe ends 56, 58 and block heat transfer between pipes ends 56, 58 and the environment surrounding pipe ends 56, 58 as suggested in Figs. 1 and 4. In the illustrative embodiment, foam insulator 26 includes two tube halves that are placed around pipe ends 56, 58 to cover pipe ends 56, 58. Foam insulator 26 is sized such that an exterior surface of foam insulator 26 is about flush with pipe coating layers 54, 64 as shown in Figs. 11 and 12. In an illustrative embodiment, the foam-insulation inserts of foam insulator 26 each comprise polyurethane foam.

[0062] Wraparound sheet 16 is wrapped around the foam- insulation inserts of foam insulator 26 and a portion of pipe coating layers 54, 64 to protect foam insulator 26 and pipe joint 18 as suggested in Figs. 5 and 6. Wraparound sheet 16 blocks water ingress into the foam-insulation inserts of foam insulator 26 and tube 12. Water ingress can cause the thermal insulation properties of the foam-insulation inserts of foam insulator 26 to decrease and pipes 40, 44 to corrode.

[0063] Wraparound sheet has a thickness 16T as shown in Fig. 9. Thickness

16T is about 10 to 40 mils in the illustrative embodiment. A mil is 1/1000 of an inch. Wraparound sheet 16 wraps around tube 12 and overlaps itself by about one to two inches as shown in Fig. 6. In an illustrative embodiment, wraparound sheet 16 covers about three to four inches of pipe coating layer 54 and about three to four inches of pipe coating layer 64.

[0064] Wraparound sheet 16 includes a heat-conducting moisture barrier layer

32, a foundation-adhesive layer 34, a barrier-foundation layer 36, and a foam- adhesive layer 38 as shown in Figs. 1 and 2. Heat-conducting moisture barrier layer 32 acts as a moisture barrier to block ingress of water such as, for example, ground water, into conduit 10 to block water from contacting the foam-insulation inserts of foam insulator 26 and pipes 40, 44. Foundation-adhesive layer 34 couples heat- conducting moisture barrier layer 32 to barrier-foundation layer 36. Barrier- foundation layer 36 provides support to wraparound sheet 16 including heat- conducting moisture barrier layer 32. Foam-adhesive layer 38 is configured to couple to the foam-insulation inserts of foam insulator 26 and pipe coating layers 54, 64 to seal pipes 40, 44 at pipe joint 18.

[0065] Heat-conducting moisture barrier layer 32 blocks water ingress into tube 12. Heat-conducting moisture barrier layer 32 has relatively high heat-transfer coefficient as compared to polyethylene to transfer heat to adhesive layer 38 during application of sleeve 14. Heat-conducting moisture barrier layer 32 comprises aluminum in an illustrative embodiment. In some embodiments, heat-conducting moisture barrier layer 32 comprises aluminum composite. In other embodiments, heat-conducting moisture barrier layer 32 comprises copper. In other embodiments, heat-conducting moisture barrier layer 32 comprises metalized polyethylene. Heat- conducting moisture barrier layer 32 has a thickness 32T as shown in Fig. 10.

Thickness 32T is about one to two mils in an illustrative embodiment.

[0066] Barrier-foundation layer 36 provides increased tensile strength and tear resistance to wraparound sheet 16. Barrier-foundation layer 36 supports wraparound sheet 16 such that heat-conducting moisture barrier layer 32 has minimal wrinkles and pinholes after application of wraparound sheet 16 to tube 12. Barrier-foundation layer 36 is a cloth-reinforcement layer in an illustrative embodiment. Barrier-foundation layer 36 is about 2.8 oz. per square yard in an illustrative embodiment. In other embodiments, barrier-foundation layer 36 is about 10 mils thick. In other

embodiments, barrier-foundation layer 36 comprises fiberglass. In other

embodiments, barrier-foundation layer 36 comprises polyester. In other

embodiments, barrier-foundation layer 36 comprises a woven material.

[0067] Foam-adhesive layer 38 is configured to couple to the foam-insulation inserts of foam insulator 26 and pipe coating layers 54, 64 to seal pipes 40, 44 at pipe joint 18 as shown in Fig. 2. Adhesive layer 38 is configured to activate at a first temperature. In some embodiments, the first temperature is about 60 degrees Celsius. In other embodiments, the first temperature is greater than about 60 degrees Celsius. Adhesive layer 38 is coupled to barrier-foundation layer 36. In one example, adhesive layer 38 is a mastic adhesive which operates to bond barrier-foundation layer 36 to both foam-insulation inserts of foam insulator 26 and pipe coating layers 54, 64 when sufficient pressure is applied.

[0068] First temperature is relatively lower than a melt temperature of pipe coating layers 54, 64. As a result, pipe coating layers 54, 56 are preserved during installation of sleeve 14. Adhesive layer 38 has a thickness 38T as shown in Fig. 10. Thickness 38T is about 20 to 30 mils. In some embodiments, a release liner (not shown) is coupled to adhesive layer 38 to protect adhesive layer 38 during transport and storage.

[0069] First adhesive strip 24 is configured to couple to pipe coating layers 54 adjacent wraparound sheet 16 as suggested in Figs. 1, 6, and 7. Second adhesive strip 28 is configured to couple to pipe coating layers 64 adjacent wraparound sheet 16. Adhesive strips 24, 28 include an inner adhesive layer 70, a foundation layer 72, an outer adhesive layer 74, and a release liner 76. [0070] Inner adhesive layer 70 is configured to couple adhesive strips 24, 28 to pipe coating layers 54, 64. Foundation layer 72 couples together inner and outer adhesive layers 70, 74. Outer adhesive layer 74 is configured to couple adhesive strips 24, 28 to heat-activated heat-shrinkable casing 30 to block heat- activated heat- shrinkable casing 30 from movement away from pipe joint 18 and block fluid communication between the environment and tube 12. Release liner 76 is coupled to outer adhesive layer 74 to protect outer adhesive layer 74 during storage and shipping. Release liners 76 are removed during application of adhesive strips 24, 28 to expose outer adhesive layer 74.

[0071] In one example, inner and outer adhesive layers 70, 74 comprise ethylene-vinyl acetate and are reactive at a second temperature. In some

embodiments, the second temperature is about 90 degrees Celsius. In other embodiments, the second temperature is greater than about 90 degrees Celsius. In other embodiments, one or both inner and outer adhesive layers 70, 74 comprise a hot-melt adhesive. In other embodiments, one or both inner and outer adhesive layers 70, 74 comprise mastic or a pressure- sensitive adhesive.

[0072] Heat-activated heat-shrinkable casing 30 is positioned over

wraparound sheet 16, adhesive strips 24, 28, and pipe coating layers 54, 64 to cover and protect pipe joint 18. Heat- activated heat-shrinkable casing 30 has heat- shrinking properties that allow heat-activated heat-shrinkable casing 30 to shrink to conform to the shape of an underlying structure when heat is applied as suggested in Figs. 8 and 9. Heat- activated heat-shrinkable casing 30 comprises a blend of high-density and low-density polyethylene in an illustrative embodiment that has been treated prior to installation to shrink in response to application of heat.

[0073] One example of a method of forming piping system 10 is shown in

Figs. 3-9. A portion of each pipe jacket 42, 46 is removed from fluid- transport units 20, 22 to expose first end 56 of first pipe 40 and second end 58 of second pipe 44 as shown in Fig. 3. Portions of pipe jackets 42, 46 are removed to provide access to pipe ends 56, 58 so that pipe jackets 42, 46 are not damaged by heat generated by welding pipes 40, 44 together to form pipe joint 18. For example, the heat generated by welding may cause unwanted disbondment of pipe jackets 42, 46 from pipes 40, 44. Heat-activated heat-shrinkable casing 30 is positioned around one of fluid-transport units 20, 22 before first and second fluid-transport units 20, 22 are brought together as shown in Fig. 3. In other embodiments, heat- activated heat-shrinkable casing 30 may be an outer wraparound-sleeve casing that does not have to be positioned around one of the fluid-transport units before fluid-transport units 20, 22 are brought together.

[0074] With ends 56, 58 of pipes 40, 44 exposed, first and second fluid- transport units 20, 22 are brought together as shown in Fig. 4. First end 56 of first pipe 40 is welded to second end 58 of second pipe 44 to form pipe joint 18. Foam- insulation inserts 26 are coupled around exposed ends 56, 58 of pipes 40, 44 after pipes 40, 44 associated with pipe joint 18 have cooled sufficiently as suggested in Fig. 4.

[0075] Wraparound sheet 16 is aligned with pipe joint 18 and wrapped around foam-insulation inserts 26, pipe coating layer 54 of first fluid-transport unit 20, and pipe coating layer 64 of second fluid-transport unit 22 as shown in Figs. 5 and 6. Adhesive layer 38 included in wraparound sheet 16 is pressed onto the foam- insulation inserts of foam insulator 26 and pipe coating layers 54, 56 to couple wraparound sheet 16 to the foam- insulation inserts of foam insulator 26 and pipe coating layers 54, 56. Wraparound sheet 16 does not require a heating step to continue applying adhesive strips 24, 28 or heat- activated heat-shrinkable casing 30 of piping system 10.

[0076] After wraparound sheet 16 is positioned around tube 12, release liners

76 are removed from adhesive strips 24, 28 such that both inner and outer adhesive layers 70, 74 are exposed as suggested in Fig. 6. First adhesive strip 24 is aligned on a first side of wraparound sheet 16 and wrapped around first fluid- transport unit 20 as suggested in Fig. 7. Second adhesive strip 28 is aligned on a second side of wraparound sheet 16 and wrapped around second fluid- transport unit 22 as shown in Fig. 11. Adhesive strips 24, 28 are pressed onto pipe coating layers 54, 56 to couple adhesive strips 24, 28 to pipe coating layers 54, 56 respectively.

[0077] After adhesive strips 24, 28 have been wrapped around tube 12, heat- activated heat-shrinkable casing 30 is slid over first adhesive strip 24, wraparound sheet 16, and second adhesive strip 28 as shown in Fig. 8. Using a torch, a user applies heat to exterior surfaces of heat-activated heat-shrinkable casing 30 to cause heat-activated heat-shrinkable casing 30 to shrink around wraparound sheet 16 and adhesive strips 24, 28 as shown in Figs. 9 and 12. As heat- activated heat-shrinkable casing 30 shrinks, pressure is applied to wraparound sheet 16 and activates adhesive layer 38.

[0078] The heat (H) applied to heat-activated heat-shrinkable casing 30 is transferred through heat- activated heat-shrinkable casing 30 to wraparound sheet 16 and adhesive strips 24, 28 in accordance with the present disclosure as suggested in Fig. 2. Heat-conducting moisture barrier layer 32 included in wraparound sheet 16 has a relatively high heat-transfer coefficient and transfers the heat (H) from heat- activated heat-shrinkable casing 30 to adhesive layer 38. The heat (H) applied to adhesive strips 24, 28 cause inner and outer adhesive layers 70, 74 to activate and bond adhesive strips 24, 28 to pipe coating layers 54, 56 and heat- activated heat- shrinkable casing 30. In the illustrative embodiment, adhesive strips 24, 28 are heated to about 150 degrees Celsius to bond adhesive strips 24, 28 to pipe coating layers 54, 64 and heat- activated heat-shrinkable casing 30.

[0079] A second embodiment of a conduit 110 is shown in Figs. 13-27.

Conduit 110, as shown for example in Fig. 13, includes a tube 112 comprising first and second pipes 40, 44 mated in end-to-end relation to establish a pipe joint 18 and a sleeve 114 coupled to tube 112 to cover pipe joint 18. Sleeve 114 includes a wraparound sheet 116 arranged to be wrapped around tube 112. Wraparound sheet 16 includes a heat-conducting moisture barrier layer 32 and is configured to provide a means for protecting pipe joint 18 from damage, transferring heat through wraparound sheet 116 during installation, and providing a diffusion barrier between pipe joint 18 and an environment surrounding tube 112. In some embodiments, heat-conducting moisture barrier layer 32 comprises aluminum. In other embodiments, heat- conducting moisture barrier layer 32 comprises copper or any other suitable heat- conducting material.

[0080] Tube 112 includes a number of groups of first and second pipes 40, 44 connected end-to-end for long distance fluid transport. As an example, tube 112 may be used to transport heated water from a cogeneration plant to residential or commercial customers as part of a district heating system. In illustrative

embodiments, pipes 40, 44 are covered by associated pipe jackets 142, 146 to insulate and protect pipes 40, 44. Pipe jackets 142, 146 are removed at ends of each pipe 40, 44 of tube 112 where pipe joint 18 is to be established as suggested in Fig. 13. After pipe joint 18 is established, sleeve 114 covers exposed pipe joint 18 to insulate and protect tube 112 at pipe joint 18.

[0081] Sleeve 114 includes a first adhesive strip 24, a foam insulator 126, wraparound sheet 116, a second adhesive strip 28, and an heat-activated heat- shrinkable casing 30 as shown in Fig. 13. To apply sleeve 14 to tube 112, foam insulator 126 is formed around pipe joint 18 as shown in Fig. 19. Wraparound sheet 116 is then wrapped around foam insulator 126 and pipe jackets 142, 146 as shown in Fig. 20. First adhesive strip 24 is wrapped around pipe jacket 142 adjacent to wraparound sheet 116 as shown in Fig. 21. Second adhesive strip 28 is wrapped around pipe jacket 146 adjacent to wraparound sheet 116 as shown in Fig. 21. Heat- activated heat-shrinkable casing 30 is positioned over wraparound sheet 116 and adhesive strips 24, 28 as shown in Fig. 22. Exterior surfaces of heat- activated heat- shrinkable casing 30 are then heated with a torch to shrink heat-activated heat- shrinkable casing 30 around wraparound sheet 116 and adhesive strips 24, 28 and activate adhesive layers included in wraparound sheet 116 and adhesive strips 24, 28 to seal the pipes establishing pipe joint 18 and couple sleeve 114 to tube 112 as shown in Fig. 23.

[0082] Conduit 110 includes tube 112 and sleeve 114 for covering tube 112 as shown in Fig. 13. Tube 112 is formed to include a first fluid-transport unit 120, a second- fluid transport unit 122, and a pipe joint 18 lying between first fluid-transport unit 120 to second-fluid transport unit 122 as shown in Figs. 13, 14, and 27. First and second fluid-transport units 120, 122 are configured to receive a fluid and transport the fluid a length of fluid-transport units 120, 122. First and second fluid-transport units 120, 122 are joined end-to-end to increase the length of travel that the fluid is transported.

[0083] In the illustrative embodiment, tube 112 is depicted as including first and second fluid-transport units 120, 122. In other embodiments, tube 112 includes a number of fluid transport units joined end-to-end in series.

[0084] First fluid- transport unit 120 includes first pipe 40 and first pipe jacket

142 covering a length of first pipe 40 as shown in Fig. 13. Second fluid-transport unit 122 includes second pipe 44 and second pipe jacket 146 covering a length of second pipe 44. First and second pipes 40, 44 are configured to receive the fluid and transport the fluid the length of pipes 40, 44. First and second pipes 40, 44 comprise steel in the illustrative embodiment. In other embodiments, first and second pipes 40, 44 comprise materials such as, for example, copper, iron, aluminum, polyethylene, or polyvinyl chloride. In some embodiments, first and second pipes 40, 44 include a surface treatment such as, for example, an epoxy or a polymeric coating. In an illustrative embodiment, first and second pipes 40, 44 are welded together to increase the length that the fluid is transported through tube 112.

[0085] First pipe jacket 142 covers first pipe 40 to insulate and protect first pipe 40 as shown in Figs. 13 and 27. First pipe jacket 142 includes insulation layer 50 and pipe coating layer 54. Second pipe jacket 146 covers second pipe 44 to insulate and protect second pipe 44. Second pipe jacket 146 includes insulation layer 60 and pipe coating layer 64.

[0086] Insulation layers 50, 60 cover pipes 40, 44 to insulate pipes 40, 44 and block heat transfer between pipes 40, 44 and the environment surrounding tube 112 as shown in Figs. 13 and 27. Insulation layers 50, 60 comprise polyurethane in the illustrative embodiment.

[0087] Pipe coating layers 54, 64 cover insulation layers 50, 60 to protect insulation layers 50, 60 from damage as shown in Figs. 13 and 27. For example, pipe coating layers 54, 64 block damage such as, for example, inadvertent piercing of insulation layers 50, 60. Pipe coating layers 54, 64 block water ingress from the environment into tube 12, and thus, block corrosion of pipes 40, 44. Pipe coating layers 54, 64 comprise high-density polyethylene in an illustrative embodiment.

[0088] Sleeve 114 is applied to tube 112 to cover and protect pipe joint 18 as suggested in Figs. 13-23. Sleeve 114 includes first adhesive strip 24, foam insulator 126, wraparound sheet 116, second adhesive strip 28, and heat- activated heat- shrinkable casing 30 as shown in Figs. 13 and 27. Foam insulator 126 provides thermal insulation between pipe joint 18 and the environment. Wraparound sheet 116 seals pipe joint 18 to block water ingress into foam insulator 126 and tube 112.

Adhesive strips 24, 28 and heat- activated heat-shrinkable casing 30 provide a secondary seal around wraparound sheet 116 and pipe joint 18.

[0089] Foam insulator 126 covers exposed pipe ends 56, 58 and pipe joint 18 to insulate pipe ends 56, 58 and block heat transfer between pipes ends 56, 58 and the environment surrounding pipe ends 56, 58 as suggested in Figs. 13 and 27. In an illustrative embodiment, foam insulator 126 is molded in-place around tube 112 as shown in Figs. 16-18. Foam insulator 126 is formed such that an exterior surface of foam insulator 126 is about flush with pipe coating layers 54, 64 as shown in Figs. 25 and 26. In an illustrative embodiment, foam insulator 126 comprises polyurethane foam.

[0090] Wraparound sheet 116 is wrapped around foam insulator 126 and a portion of pipe coating layers 54, 64 to protect foam insulator 126 and pipe joint 18 as suggested in Figs. 19 and 20. Wraparound sheet 116 blocks water ingress into foam insulator 126 and tube 112. Water ingress can cause the thermal insulation properties of foam insulator 126 to decrease and pipes 40, 44 to corrode.

[0091] Wraparound sheet has a thickness 116T as shown in Fig. 24.

Thickness 116T is about 10 to 40 mils in an illustrative embodiment. A mil is 1/1000 of an inch. Wraparound sheet 116 wraps around tube 112 and overlaps itself by about one to two inches as shown in Fig. 20. In an illustrative embodiment, wraparound sheet 116 covers about three to four inches of pipe coating layer 54 and about three to four inches of pipe coating layer 64.

[0092] Wraparound sheet 116 includes a heat-conducting moisture barrier layer 32 and an adhesive layer 38 as shown in Figs. 13 and Fig. 27. Heat-conducting moisture barrier layer 32 acts as a moisture barrier to block ingress of water such as, for example, ground water, into conduit 110 to block water from contacting foam insulator 126 and pipes 40, 44. Adhesive layer 38 couples wraparound sheet 116 to pipe jackets 142, 146 and seals pipe joint 18.

[0093] Heat-conducting moisture barrier layer 32 blocks water ingress into tube 112. Heat-conducting moisture barrier layer 32 has relatively high heat-transfer coefficient as compared to polyethylene to transfer heat to adhesive layer 38 during application of sleeve 114. Heat-conducting moisture barrier layer 32 comprises aluminum in an illustrative embodiment. In some embodiments, heat-conducting moisture barrier layer 32 comprises aluminum composite. In other embodiments, heat-conducting moisture barrier layer 32 comprises copper. In other embodiments, heat-conducting moisture barrier layer 32 comprises metalized polyethylene. Heat- conducting moisture barrier layer 32 has a thickness 32T as shown in Fig. 24.

Thickness 32T is about 1 to 2 mils in the illustrative embodiment.

[0094] Adhesive layer 38 is configured to couple to foam- insulation insert 126 and pipe coating layers 54, 64 to seal pipes 40, 44 at pipe joint 18 as shown in Fig. 27. Adhesive layer 38 is configured to activate at a first temperature. In some

embodiments, the first temperature is about 60 degrees Celsius. In other

embodiments, the first temperature is greater than about 60 degrees Celsius.

Adhesive layer 38 is coupled to heat-conducting moisture barrier layer 32. In one example, adhesive layer 38 is a mastic adhesive which operates to bond wraparound sheet 116 to both foam-insulation insert 126 and pipe coating layers 54, 64 when sufficient pressure is applied.

[0095] First temperature is relatively lower than a melt temperature of pipe coating layers 54, 64. As a result, pipe coating layers 54, 56 are preserved during installation of sleeve 114. Adhesive layer 38 has a thickness 38T as shown in Fig. 24. Thickness 38T is about 20 to 30 mils. In some embodiments, a release liner (not shown) is coupled to adhesive layer 38 to protect adhesive layer 38 during transport and storage.

[0096] First adhesive strip 24 is configured to couple to pipe coating layer 54 adjacent wraparound sheet 116 as suggested in Figs. 13, 20, and 21. Second adhesive strip 28 is configured to couple to pipe coating layer 64 adjacent wraparound sheet 116. Adhesive strips 24, 28 include an inner adhesive layer 70, a foundation layer 72, an outer adhesive layer 74, and a release liner 76.

[0097] Inner adhesive layer 70 is configured to couple adhesive strips 24, 28 to pipe coating layers 54, 64 as shown in Fig. 20. Foundation layer 72 couples together inner and outer adhesive layers 70, 74. Outer adhesive layer 74 is configured to couple adhesive strips 24, 28 to heat- activated heat-shrinkable casing 30 to block heat-activated heat-shrinkable casing 30 from movement away from pipe joint 18 and block fluid communication between the environment and tube 112. Release liner 76 is coupled to outer adhesive layer 74 to protect outer adhesive layer 74 during storage and shipping. Release liners 76 are removed during application of adhesive strips 24, 28 to expose outer adhesive layer 74.

[0098] In one example, inner and outer adhesive layers 70, 74 comprise ethylene-vinyl acetate and are reactive at a second temperature. In some

[0099] Heat-activated heat-shrinkable casing 30 is positioned over

wraparound sheet 116, adhesive strips 24, 28, and pipe coating layers 54, 64 to cover and protect pipe joint 18 as shown in Fig. 22. Heat-activated heat-shrinkable casing 30 has heat- shrinking properties that allow heat-activated heat-shrinkable casing 30 to shrink to conform to the shape of an underlying structure when heat is applied as suggested in Figs. 22 and 23. Heat-activated heat-shrinkable casing 30 comprises a blend of high-density and low-density polyethylene in the illustrative embodiment that has been treated prior to installation to shrink in response to application of heat.

[00100] One example of a method of forming conduit 110 is shown in Figs. 14-

23. A portion of each pipe jacket 142, 146 is removed from fluid-transport units 120, 122 to expose first end 56 of first pipe 40 and second end 58 of second pipe 44 as shown in Fig. 14. Portions of pipe jackets 142, 146 are removed to provide access to pipe ends 56, 58 and so that pipe jackets 142, 146 are not damaged by heat generated by welding pipes 40, 44 together to form pipe joint 18. For example, the heat generated by welding may cause unwanted disbondment of pipe jackets 142, 146 from pipes 40, 44. Heat- activated heat-shrinkable casing 30 is positioned around one of fluid-transport units 120, 122 before first and second fluid-transport units 120, 122 are brought together as shown in Fig. 14. In other embodiments, heat- activated heat- shrinkable casing 30 may be an outer wraparound- sleeve casing that does not have to be positioned around one of the fluid-transport units before fluid-transport units 120, 122 are brought together.

[00101] With ends 56, 58 of pipes 40, 44 exposed, first and second fluid- transport units 120, 122 are brought together as shown in Fig. 15. First end 56 of first pipe 40 is welded to second end 58 of second pipe 44 to form pipe joint 18. Foam insulator 126 is formed around exposed ends 56, 58 of pipes 40, 44 after pipes 40, 44 associated with pipe joint 18 have cooled sufficiently as shown in Figs. 16-18.

[00102] To form foam insulator 126, an insulation unit mold 84 is positioned around tube 112 to cover pipe joint 18 and pipe jackets 142, 146 as shown in Fig. 16. A foam applicator 86 is then coupled to insulation unit mold 84 to supply liquid foaming material to a mold cavity 88 formed between insulation mold unit 84 and tube 112. Liquid foaming material is then delivered into mold cavity 88 by foam applicator 86 to form foam insulator 126 around pipe joint 18 as shown in Fig. 17.

[00103] Liquid foaming material includes blowing agent such as a gas, for example, that expands the liquid foaming material to forms insulative cells in the liquid foaming material as the liquid foaming material solidifies. The gas in the liquid foaming material diffuses out of liquid foaming material as the foaming material solidifies. Reducing the amount of gas that diffuses out of the liquid foaming material increases the size of the cells and, thus, increases the thermal insulation properties of foam insulator 126. In the illustrative embodiment, heat-conducting moisture barrier layer 32 included in wraparound sheet 116 acts as a diffusion barrier to block the gas from diffusing out of the liquid foaming material as the liquid foaming material solidifies. As such, foam insulator 126 has larger cells and thus, increased thermal insulation properties as compared with a wraparound sheet without heat-conducting moisture barrier layer 32.

[00104] Insulation unit mold 84 is maintained in position around pipe joint 18 while the liquid foaming material expands and an outer surface solidifies as suggested in Fig. 18. Foam insulator 126 is established after the liquid foaming material has expanded and solidified and insulation unit mold 84 is removed. In the illustrative embodiment, insulation unit mold 84 is removed from tube 112 and wraparound sheet 116 is wrapped around foam insulator 126 after foam insulator 126 has partially solidified, but has not completed the forming process. Wraparound sheet 116 blocks the gases from diffusing out of the foam insulator 126 to provide a more complete forming process.

[00105] Wraparound sheet 116 is aligned with pipe joint 18 and wrapped around foam insulator 126, pipe coating layer 54 of first fluid-transport unit 120, and pipe coating layer 64 of second fluid-transport unit 122 as shown in Figs. 19 and 20. Adhesive layer 38 included in wraparound sheet 116 is pressed onto foam insulator 126 and pipe coating layers 54, 56 to couple wraparound sheet 116 to foam insulator 126 and pipe coating layers 54, 56. Wraparound sheet 116 does not require a heating step to continue applying adhesive strips 24, 28 or heat- activated heat-shrinkable casing 30 of conduit 110. After wraparound sheet 116 is wrapped around foam insulator 126, heat-conducting moisture barrier layer 32 acts as a diffusion barrier and blocks gas from escaping the liquid foaming material while the liquid foaming material is solidifying to form foam insulator 126.

[00106] After wraparound sheet 116 is positioned around tube 112, release liners 76 are removed from adhesive strips 24, 28 such that both inner and outer adhesive layers 70, 74 are exposed as suggested in Fig. 20. First adhesive strip 24 is aligned on a first side of wraparound sheet 116 and wrapped around first fluid- transport unit 120 as suggested in Fig. 21. Second adhesive strip 28 is aligned on a second side of wraparound sheet 116 and wrapped around second fluid- transport unit 122 as shown in Fig. 25. Adhesive strips 24, 28 are pressed onto pipe coating layers 54, 56 to couple adhesive strips 24, 28 to pipe coating layers 54, 56 respectively as shown in Figs. 25 and 26.

[00107] After adhesive strips 24, 28 have been wrapped around tube 112, heat- activated heat-shrinkable casing 30 is slid over first adhesive strip 24, wraparound sheet 116, and second adhesive strip 28 as shown in Fig. 22. Using a torch, a user applies heat to exterior surfaces of heat-activated heat-shrinkable casing 30 to cause heat-activated heat-shrinkable casing 30 to shrink around wraparound sheet 116 and adhesive strips 24, 28 as shown in Figs. 23 and 26. As heat- activated heat-shrinkable casing 30 shrinks, pressure is applied to wraparound sheet 116 and activates adhesive layer 38.

[00108] The heat applied to heat- activated heat-shrinkable casing 30 is transferred through heat- activated heat-shrinkable casing 30 to wraparound sheet 116 and adhesive strips 24, 28 in accordance with the present disclosure. Heat-conducting moisture barrier layer 32 included in wraparound sheet 116 has a relatively high heat- transfer coefficient and transfers the heat from heat- activated heat-shrinkable casing 30 to adhesive layer 38. The heat applied to adhesive strips 24, 28 cause inner and outer adhesive layers 70, 74 to activate and bond adhesive strips 24, 28 to pipe coating layers 54, 56 and heat-activated heat-shrinkable casing 30. In the illustrative embodiment, adhesive strips 24, 28 are heated to about 150 degrees Celsius to bond adhesive strips 24, 28 to pipe coating layers 54, 64 and heat- activated heat-shrinkable casing 30.

Claims

1. A conduit comprising

a sleeve including a heat- activated heat-shrinkable casing formed to include a tube-receiving passageway, a foam insulator positioned to lie in the tube- receiving passageway and adapted to mate with and surround portions of first and second pipes that cooperate to form a tube and to cover a pipe joint formed between the first and second pipes, and a cold-applied tubular wraparound sheet arranged to lie in the tube-receiving passageway formed by the heat-activated heat-shrinkable casing and formed to include an insulator-receiving passageway,

wherein the foam insulator is located in the insulator-receiving passageway formed in the cold-applied tubular wraparound sheet, and

wherein the cold-applied tubular wraparound sheet includes a foam- adhesive layer mating with an exterior portion of the foam insulator and a heat- conducting moisture barrier layer interposed between the foam-adhesive layer and the heat-activated heat-shrinkable casing and configured to provide means for transferring heat applied to the heat- activated heat-shrinkable casing to the foam-adhesive layer and for blocking flow of liquid accumulating in a space provided between an interior surface of the heat- activated heat-shrinkable casing and an exterior surface of the cold-applied tubular wraparound sheet to the foam-adhesive layer and to the foam insulator.

2. The conduit of claim 1, wherein the cold- applied tubular wraparound sheet further includes a barrier-foundation layer interposed between the heat-conducting moisture barrier layer and the foam-adhesive layer and arranged to mate with the foam-adhesive layer and a foundation-adhesive layer arranged to interconnect the heat-conducting moisture barrier layer and the barrier foundation layer, and the foundation-adhesive layer, the barrier-foundation layer, and the foam- adhesive layer cooperate to provide means for transferring heat discharged from the heat-conducting moisture barrier layer to the foam insulator.

3. The conduit of claim 2, wherein the heat-conducting moisture barrier layer comprises aluminum.

4. The conduit of claim 2, wherein the heat-conducting moisture barrier layer comprises copper.

5. The conduit of claim 2, wherein the heat-conducting moisture barrier layer comprises metalized polyethylene.

6. The conduit of claim 1, further comprising a first pipe jacket associated with the first pipe, and a second pipe jacket associated with the second pipe and arranged to lie in spaced-apart relation to the first pipe jacket to locate the foam insulator therebetween, and wherein a first-end portion of the foam-adhesive layer mates with the first pipe jacket associated with the first pipe to transfer heat discharged from the heat-conducting moisture barrier layer to the first pipe jacket, an opposite second-end portion of the foam-adhesive layer mates with the second pipe jacket associated with the second pipe to transfer heat discharged from the heat- conducting moisture barrier layer to the second pipe jacket, and a middle portion of the foam-adhesive layer is interposed between the first-end and second-end portions and is mated with the exterior portion of the foam insulator to transfer heat discharged from the heat-conducting moisture barrier layer to the foam insulator.

7. The conduit of claim 6, further comprising a first pipe and a second pipe arranged to lie in end-to-end relation to the first pipe to define a pipe joint therebetween, and wherein the first pipe jacket is arranged to mate with and surround an exterior portion of the first pipe, the second pipe jacket is arranged to mate with and surround an exterior portion of the second pipe, and the foam insulator is arranged to mate with and surround exterior portions of each of the first and second pipe and to cover the pipe joint defined between the first and second pipes.

8. The conduit of claim 7, wherein the first pipe jacket is configured to provide means for blocking ingress of water from the surroundings to the first pipe and the second pipe jacket is configured to provide means for blocking ingress of water from the surroundings to the second pipe.

9. The conduit of claim 8, wherein each of the first and second pipe jackets comprises high-density polyethylene.

10. The conduit of claim 8, wherein the sleeve further includes a first adhesive strip that is interposed between and mated with each of the first pipe jacket and a first portion of the heat- activated heat-shrinkable casing and a second adhesive strip that is interposed between and mated with each of the second pipe jacket and a second portion of the heat- activated heat-shrinkable casing, the cold- applied tubular wraparound sheet is arranged to lie on the foam insulator in a position between the first and second adhesive strips, and the heat-conducting moisture barrier layer is positioned to lie between the first and second adhesive strips.

11. The conduit of claim 10, wherein the foam-adhesive layer is configured to activate at a first temperature, each of the first and second adhesive strips comprises an outer adhesive layer that is configured to activate at a second temperature that is higher than the first temperature, and the heat-conducting moisture barrier layer is positioned to lie in a space provided between the outer adhesive layer of the first and second adhesive strips.

12. The conduit of claim 11, wherein the outer adhesive layer of each of the first and second adhesive strips comprises ethylene-vinyl acetate.

13. The conduit of claim 11, wherein the first temperature is about 60 degrees Celsius and the second temperature is about 90 degrees Celsius.

14. The conduit of claim 1, wherein the heat-conducting moisture barrier layer is configured to provide means for blocking diffusion of a blowing agent gas included in liquid foaming material provided to form the foam insulator to the surrounding environment as the liquid foaming material solidifies during completion of formation of the foam insulator on the first and second pipes to maximize cell size in the foam insulator and enhance thermal insulation properties of the cold-applied tubular wraparound sheet.

15. The conduit of claim 14, wherein the heat-conducting moisture barrier layer comprises aluminum.

16. The conduit of claim 1, further comprising a tube arranged to extend through the tube-receiving passageway formed in the heat- activated heat- shrinkable casing, wherein the tube includes a first fluid-transport unit comprising a first pipe and a first pipe jacket covering an exterior surface of a first end portion of the first pipe and a second fluid-transport unit comprising a second pipe arranged to lie in end-to-end relation to the first pipe to establish a pipe joint therebetween and a second pipe jacket covering an exterior surface of a first-end portion of the second pipe, the foam insulator mates with exposed portions of the first and second pipes to cover the pipe joint, a first portion of the foam-adhesive layer of the cold-applied tubular wraparound sheet mates with the first pipe jacket, and a second portion of the foam-adhesive layer of the cold-applied wraparound sheet mates with the second pipe jacket.

17. The conduit of claim 16, wherein the sleeve further includes a first adhesive strip that is interposed between and mated with each of the first pipe jacket and a first portion of the heat- activated heat-shrinkable casing and a second adhesive strip that is interposed between and mated with each of the second pipe jacket and a second portion of the heat- activated heat-shrinkable casing and the cold- applied tubular wraparound sheet is arranged to lie on the foam insulator in a position between the first and second adhesive strips to locate the heat-conducting moisture barrier layer between the first and second adhesive strips.

18. The conduit of claim 17, wherein the foam- adhesive layer is configured to activate at a first temperature, each of the first and second adhesive strips comprises an outer adhesive layer that is configured to activate at a second temperature that is higher than the first temperature, and the heat-conducting moisture barrier layer is positioned to lie between the outer adhesive layer of the first and second adhesive strips.

19. The conduit of claim 18, wherein the heat-conducting moisture barrier layer comprises aluminum.