AU2016278346B2

AU2016278346B2 - Improvements in apparatus for repairing pipe joints

Info

Publication number: AU2016278346B2
Application number: AU2016278346A
Authority: AU
Inventors: Christopher Meredith
Original assignee: Individual
Current assignee: Individual
Priority date: 2015-06-19
Filing date: 2016-05-20
Publication date: 2020-07-09
Anticipated expiration: 2036-05-20
Also published as: NZ737186A; AU2016278346A2; AU2016278346A1; WO2016201484A1

Abstract

There is a heating liner for use as part of an apparatus for repairing a pipe connection joint. The apparatus is of a type referred to and includes a resin treated patch matrix sleeve (19) insertable into the connection joint to extend across the joint and an inflatable packer body (13) within the patch matrix sleeve (19) for expansion against internal surfaces (20) of the joint. The heating liner (18) is adapted for placement between said inflatable packer body (13) and patch matrix sleeve (19) prior to expansion. The heating liner (18) includes one or more lengths of heating element (7, 8) extending over an area of the surface of said heating liner for heating the patch matrix sleeve to reduce resin curing time.

Description

IMPROVEMENTS IN APPARATUS FOR REPAIRING PIPE JOINTS FIELD OF THE INVENTION

This invention relates to pipe joint/crack/break repairs & sealing. More particularly, although not exclusively, it discloses improvements to repair apparatus which reduce the time required to complete a repair.

BACKGROUND TO THE INVENTION Configurations of pipe connections to which this invention generally relates are described in the prior art. For example see Australian Patent 2002300539 which is also by the present inventor. The pipe joint repair apparatus and method disclosed in Australian Patent 2002300539 is hereby incorporated by reference into this specification. Such connections are typically, although not exclusively, used to link a main line such as a street sewer to a branch line extending fiom a domestic dwelling or the like. When repairing a junction connection joint crack, break or leak between the branch and main line one known method is to install a patch matrix sleeve. This is subsequently expanded by an inflatable body against the adjacent internal surfaces of the main and branch lines on each side of the joint. The sleeve may be formed from a resin impregnated coated woven felt or polyester or fiberglass mat fonning a patch matrix which cures over time to repair and seal the pipe junction connection or joint or crack from the inside. With the resins currently used this curing time is of the order of 75 minutes or longer and during this period the repair crew and service vehicle are unavailable for other work. It is therefore of economic advantage to reduce the curing time of the resin and thus the total time required for the repair. The present invention is directed to this object.

It is a further object of the invention to provide an improved repair apparatus of the above type which is adapted for use with non-branched straight or curved sections of pipe.

SUMMARY OF THE INVENTION In accordance with one aspect of the invention a heating liner is disclosed for use with a repair apparatus for a pipe connection joint, said apparatus being of a type referred to and including a resin treated patch matrix sleeve insertable into said connection to extend across said joint and an inflatable packer body within said patch matrix sleeve for expansion thereof against internal surfaces of said joint wherein said heating liner is adapted for placement between said inflatable packer body and patch matrix sleeve prior to expansion and said heating liner including one or more lengths of heating element extending over an area of the surface of said heating liner for heating the patch matrix sleeve to reduce resin curing time.

In accordance with a first embodiment of the invention the liner and apparatus may be adapted for use in repairing a crack, break or leak at a pipejunction connection joint having a main portion and a branch portion.

In accordance with a second embodiment of the invention the liner may be adapted for use in repairing a crack, break or leak in a pipe and at a joint joint in a non branched straight or curved section of pipe.

A method of repairing a pipe junction connection joint of the type referred to is also disclosed, said method including the steps of: - disposing a heating liner between an inner inflatable packer body and an outer resin treated patch matrix sleeve, - inserting said inflatable packer body, heating liner, and patch matrix sleeve into the joint, - inflating said inflatable body to expand said patch matrix sleeve outward against a crack, break or leak in the internal surface of said joint, and

- activating said heating liner to reduce the curing time of said resin.

In accordance with a further aspect of the invention apparatus is disclosed for repair of a pipe joint crack, break or leak which in use includes an assembly comprising a heating liner disposed between an inner inflatable packer body and an outer resin treated patch matrix sleeve.

Preferably the heating liner comprises a foamed neoprene sheet material ranging in thickness from about 1 mm to about 6 mm. Preferably it is made with multiple layers of foamed neoprene sheets.

It is further preferred that said heating liner is formed from at least one generally rectangular sheet with Velcro side edge.

It is further preferred that said heating element comprises one or more lengths of electrical resistance wire or heating cable.

In accordance with said first embodiment of the invention the heating liner has main and branch sheets which are fitted with separate but connectable lengths of said electrical resistance wire or heating cable.

It is further preferred that said resistance wires or heating cable are disposed on an outer surface of the liner and follow a serpentine path over said surface.

It is further preferred that the main sheet is formed into a main cylindrical portion by wrapping said Velcro edges together.

It is further preferred that said main cylindrical portion is formed with an aperture and one end of said branch cylindrical portion is attached over said aperture by stitching, adhesive or the like.

BRIEF DESCRIPTION OF THE DRAWINGS Currently preferred embodiments of the invention will now be described with reference to the attached drawings in which:

Figure 1 show plan views of main and branch sheets for forming into a heating liner in accordance with a first embodiment the invention,

Figure 2 is an assembly drawing showing the sheets of figure 1 partially formed into the cylindrical main and branch portions of the liner

Figure 3 shows the liner assembled over an inflatable packer body in accordance with the invention,

Figure 4 shows the assembled liner and deflated packer body of figure 3 with the patch matrix sleeve fitted over,

Figure 5 shows the assembly of figure 4 located in a pipe joint (shown schematically) with the packer body inflated to expand the patch matrix sleeve into sealing contact with the inside surfaces of said joint,

Figures 5 and 5A show examples of typical pipe junction connection sections in which the patch matrix sleeve (shown figuratively in broken lines) is fitted,

Figure 6 shows a plan view of a single sheet for forming into a heating liner for a non-branched section of pipe in accordance with a second embodiment of the invention,

Figure 7 shows the sheet of figure 6 partially formed into the cylindrical heating liner,

Figure 8 shows the liner of figure 7 assembled over a cylindrical pneumatic bladder in accordance with the invention,

Figure 9 shows the assembled liner and bladder of figure 8 with the patch matrix sleeve fitted over,

Figure 10 shows the assembly of figure 9 located in a non-branched section of pipe (shown figuratively in broken lines) with the bladder inflated to expand the sleeve into sealing contact with the inside of the pipe, and

Figures I Iand 12 show examples of typical non-branched straight and curved pipe sections in which the liner (shown figuratively in broken lines) is fitted

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring first to figure 1 there are two foam neoprene sheets which in flattened form are generally rectangular in shape. The main sheet I has a central aperture 2 and a strip of Velcro 3 along one side. The branch sheet 4 has an undulating upper edge 5 as shown in order to provide a suitable end profile for engaging the circumference of the aperture in the assembled liner as described hereunder.

One side 6 of this sheet is stitched to the opposite side 6A to form a barrel shown as item 12 in figures 2 to 4. Both sheets are overlaid with electrical resistance heating elements 7, 8 which with this embodiment preferably comprise 3 mm diameter Nichrome cable. Other heating elements may be used however within the scope of the invention. With the current embodiment shown the cable follows a serpentine path to substantially cover the outside areas of the sheets. Although not shown the cable may also be arranged to encircle the central aperture 2 of sheet 1. With the current embodiment the cable is positioned in place by location holes and neoprene strips 9 stitched over the upper and lower extremities of the heating cables as shown. The strips however may also be extended to cover the whole length of the cables. Adhesive tape or other adhesive or mechanical fastenings such as staples or eyelets may also be used within the scope of the invention. The heating element 7 on the main sheet is spliced and crimped to wire 9A which is fitted with a power plug 10. This connects to an electrical supply (not shown) which preferably but not essentially may be 12 to 80 volts DC.

With the current embodiments the preferred power supply is as follows: Volts (E)= Variable from 0 to 80Vdc and more preferably 60Vdc Power (P)= <17 w/mtr Current (1)= <4 Amps Ohms (R)= Preferably varies from 1.0 to 60.0 dependant on the length of heating cable used vs target cable temperature requirement of<70 degrees C. Basically the shorter the length of heating cable the higher the resistance (R) cable needed to achieve the target heating temperature.

As shown in figures 2 and 3 the sheets 1 and 4 in use can be formed into main and branch cylinders 11, 12 and assembled (by for example stitching, stapling or adhesive ) around an inflatable pneumatic bladder 13 with corresponding main leg and branch arm portions 14, 15. More specifically the side edges of each sheet may be joined by stitching to form cylinders around said main leg and branch arm portions of the bladder. The heating elements 7, 8 are preferably, although not essentially, located on the outside of the assembled liner and are joined by any type of suitable electric connectors 16. The end 17 of branch cylinder 12 formed by edge 5 is stitched, stapled or secured by adhesive over the aperture 2 in the main cylinder 11. While with this embodiment the angle between the cylinders is shown as 90 degrees in practice this may change according to installation or design requirements.

Referring now to figures 4 to 5B the heating liner, now indicated generally as 18 upon joining main and branch cylinders 11 and 12 (for example by stitching, staples or adhesive) is disposed over the initially deflated bladder 13 (figure 4) and then inside a flaccid resin coated or impregnated patch matrix sleeve 19. Preferably the sleeve 19 may be formed from a coated woven felt, or polyester or fiberglass mat forming a patch matrix with the outer surface coated with resin. Other materials however may be used for the sleeve within the scope of the invention. After insertion of the bladder, liner and sleeve into the pipe connection and upon inflation of the bladder through conduits using known techniques (see for example Patent 2002300539) the sleeve 19 is pressed against the inside 20 of the pipes to effect a seal. The subsequent application of an electrical current from any suitable power source to the resistance wires 7, 8 through plug 10 then warms the liner and raises the temperature of the sleeve to preferably about 20 to 50 degrees C above ambient temperature to reduce the resin curing time from a typical duration of about 75 to 90 minutes to about 25 to 35 minutes. This has been found to result in substantial savings in labour and equipment costs where a typical repair crew of 2 to 3 workers and special purpose vehicle and equipment are required to be in attendance until the cure is completed.

With the second embodiment of the invention shown in figures 6 to 12 the components of the apparatus corresponding to the first embodiment are identified by the same numbers with the addition of the prime symbol (')to differentiate them from those of figures 1to 5. In this case the sheet liner 1' shown in figures 6, 7 and 8 is formed into a single cylinder 11' and assembled around a cylindrical deflated pneumatic bladder 13' using the Velcro strip 3'. As with the first embodiment the heating element 7' is preferably located on the outside of the assembled liner but inside the resin coated sleeve 19' as shown in figure 9. The assembly is then placed inside a non-branched pipe section where it is expanded and the sleeve 19' pushed out against the inside 20' of said pipe. The procedure for inflating the bladder and heating the liner is the same as for the first embodiment. As shown in figures 11 and 12 the sheet liner 11' according to this second embodiment may be used to repair either straight 21 or a curved section 22 of non branched pipe.

It will thus be appreciated that this invention at least in the form of the embodiments described provides novel and useful improvements to apparatus for the repair of pipe joints. Clearly however the examples disclosed are only the currently preferred forms of the invention and a wide variety of modifications may

be made which would be apparent to a person skilled in the art. For example the material of which the liner is constructed and the diameter, layout and position of the heating wires and the size, shape and configuration of the sheets making up the liner may all be changed following further research and development work by the inventor.

Claims

The claims

1. A heating liner for use as part of an apparatus for repairing a pipe connection joint, said apparatus being of a type which includes a resin treated patch matrix sleeve insertable into said connection joint to extend thereacross and an inflatable packer body within said patch matrix sleeve for expansion against an internal surface of said joint, said heating liner being adapted for placement between said inflatable packer body and patch matrix sleeve prior to expansion and said heating liner having electrical resistance wire arranged thereon whereby substantially the entire length of said electrical resistance wire is disposed on an outer surface of said heating liner for heating the patch matrix sleeve to reduce curing time and said electrical resistance wire extending substantially over all portions of said outer surface and said electrical resistance wire being held in place on said outer surface by stitched neoprene strips.

2. The heating liner as claimed in claim 1 wherein said liner includes one or more layers of a foamed neoprene sheet material.

3. The heating liner as claimed in claim 2 wherein said liner includes main and branch sheets which are fitted with separate but connectable lengths of said electrical resistance wire.

4. The heating liner as claimed in claim 3 wherein said main and branch sheets are formed into main and branch cylinders by joining side edges thereof together.

5. The heating liner as claimed in claim 4 where said side edges are joined by stitching or stapling.

Received)7/09/2016

6. The heating liner as claimed in claim 5 wherein said electrical resistance wire is disposed on an outer surface of the liner and follows a serpentine path to substantially cover said outer surface.

7. A method of repairing a pipe connection joint, said method including the steps of: - procuring a heating liner as claimed in claim 1 - disposing said heating liner between an inner inflatable packer body and an outer resin treated patch matrix sleeve, - inserting said inflatable packer body, heating liner, and patch matrix sleeve into saidjoint, - inflating said inflatable body to expand said patch matrix sleeve outward against a crack, break or leak in the internal surface of said joint, and - activating said heating liner to reduce the curing time of said resin treated patch matrix sleeve.

8. The method as claimed in claim 7 wherein said heating liner is activated by connection to an electrical power supply sufficient to raise the temperature of the patch matrix sleeve to about 20 to 50 degrees C above ambient temperature.

9. The method as claimed in claim 8 wherein said power supply has the following characteristics: Volts (E) = 60Vdc Power (P) =<17 w/mtr Current (I) =<4 Amps

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Received)7/09/2016

10. The method as claimed in claim 7 wherein said heating liner is assembled around the inner inflatable packer body.

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