TECHNICAL FIELD

10001 ] The present invention relates to strips: windable to font* pipes. BACKGROUND

1 _. 0002 ^" ] The applicant has developed various technologies so allow trenehless pipe rehabilitation. Some of these technologies will also find application outside trenchless pipe rehabilitation.

|0003 ^' | Typically* large spools of strip, sometimes referred to as "profile", are wound tssitig a winding machine into helically wound pipe. In order to maximise the efficiency of this process, it is desirable to provide high capaerty spools of strip. That is,, it is desirable to provide long lengths of strip, ideally on a single spool

SUMMARY

[0004] According to a first aspect of ail embodiment of the invention ^' _s , there is pro ided a. stri assembly helically windable to form a pipe, the strip assembly including a pair of joined elongate strips, each strip when straight including;

a base lyin in or adjacent to a base plane;

at least one longitudinal rib upstanding from the base;

a pair of spaced apart longitudinal parallel edges; and

a, joining end surface,

wherein the joining end surfaces lie i a joining plane, the joining plane intersecting the base plane to form an intersecting line, the intersecting line defining an angle Θ with respect to the parallel edges, the angle Θ less than 80 degrees, and,

wh rein fee joining plane forms an. angle β with respect to the base plane, the angle β being less than 75 degrees.

10005 j In one form, the angle Θ is less than 73 degrees. [0006] In one form, the angle β is less than 65 degrees, [0007] In one form, the angle Θ is less than.65 degrees, [0008 ] In one form;, the angle J} is less than 55 degrees. ^■ 7

[00091 la one form, the angle Θ is between 35 and 55 degrees.

[0010] In one form, the angle β is between 35 and 55 degrees.

1001 I ] in one form., the pair of joined strips: are joined by an adhesive.

10012] la one form, the adhesive is a cyanoaerylate adhesive.

100] 3 ] In one form, each strip includes a plurality of ribs, each rib upstanding from the base.

[ 1 ⁾ 0141 According to a second aspect of an em odiment of the present indention, there, is provided a pipe helically wound from the strip assembly according to the first aspeet of the invention.

[ 00151 Accord ing to a third aspect; of an embodiment: of the i nven tio , there is pro vided a strip assembl helically windabk to form, a pipe, the strip assembly including a pair of joined elongate strips, each strip having a strip width and a stri height and each strip including:

a base;

at least one longitudinal rib upstanding torn the- base;

a paii" of spaced apart longitudinal parallel edges; and

an angled join ing end surface.

whereby each joining end surface has a joining width, the joi ning width at least 1.5% greater than the strip width, and

w ereby each joining end surface has a joining height, the joining height at least 3.5% greater than the strip height.

[0016] In one form the joining width is at least 5% greater than the strip width.

[0017] In one form the joining height js at least 10% greater than the strip height.

[00 IS] in one form the joining width is at least 10% greater than the strip width.

[0019] In one form the joining height is at least 20% greater than the strip height.

[0020] According to a■fourth aspect of aa embodiment of the present, invention, there is provided a method of joining a first strip to a second strip, each strip including: a base having first and second spaced-apart parallel longitadmal edges; and at least one longitudinal rib upstanding from the base, the method including the steps of:

( 1) positioning an end portion of the first strip: over an end portion of the second strip such that: the first longitudinal edge of die first strip overlaps, and is. substantially aligned with the first longitudinal edge of the second strip, and the second longitudinal edge of the first strip overlaps and is substantially aligned -with the second longitudinal edge of the second strip;

(2) cutting the overlapping end portions of the first and second strips to produce a pair of adj cent angled joining end surfaces;

(3) treating at least one of the pair of joining end surfaces:

(4) pressing the pair of joining end surfaces against each, other so as to create compression, and holding the compression for a time period, the time period sufficient to create a bond,

ihereby bonding the first strip to the second strip.

[0021] In one foirn, the method further includes the Step of:

re-eutting and ihereby re-forming the pair of joining end surfaces while the base of the first strip is aligned with the base of the sec ond strip,

wherein, the rc-cutting step occurring between the cutting an the treating steps.

[ 0022] In one form, the method further includes the step of:

re-positioning the relative positions of the joining end surface of the first strip and the joinin end surface of the second strip such that they are aligned,

wherein, the re-positioning step occurs between the cutting: and the re-cutting steps.

[002,3] hi one form, the treatin step i cludes applying a cyanoaeryiate adhesive to one of the pair of joining end surfaces.

[0024] In one form, the treating step includes heating both of the pair of joining end surfaces. BRIEF DESCRIPTION OF DRAWINGS

[0025 ] Embodiments of the present invention will be discussed with reference to the accompanying drawings wherein:

[0026 ] Figure. 1 shows an isometric view of a strip assembly hel ically wind bie to form a pipe;

10027 ] Figure 2A is an. end view of the strip assembly of Figure i ;

100281 Figure 2B is a pl an view of a portion of the stri p assembly of Figure 1 ;

[0029] Figure 3A is a similar view to that of Figure .1 , but includes a diagrammatic vie of a joining plane to help illustrate the joining of a pair of elongate strips; [ 00301 Figure 3B is a plan view of a portion of a second of the elongate strips -shown in Figure 3 A;

[0031 ] Figure 3.C is a side view of a portion of the second of the elongate strips shown in Figure 3 A;

[0032] Figure 3D is an angled side view of a portion of the second of the elongate strips shown in Figure 3 A, the view angle aligned along a joining end surface

[0033 ) Figures 4A and 4B are diagrammatic side and plan -views respectively that illustrate a step in joining the pair of elongate strips shown in Figure 1;

[0034 ] Figures 5 A. and 5B are diagrammatic side and plan views respecti vely that illustrate a step in joining the pair of elongate strips shown in Figure 1; j 0035 ] Figures 6A and 6B are diagrammatic side and plan views respectively that illustrate a step in joining the pair of elongate strips shown in Figure 1;

[0036] Figures 7A and 7.B are diagrammatic side and plan views respectively that, illustrate a step in joining the pair of elongate strips shown in/Figure 1 ;

[ 0037 J Figures 8A and 8B are diagrammatic side and plan views respectively that illustrate a step in joining the pair of elongate strips shown in Figure 1;

[00381 Figures 9 A, and 9B are diagrammatic side and plan views respectively that illustrate a step in joining the pair of elongate strips shown in Figure 1 ;

[0039] Figures lO nd lOB are diagrantmatie side and plan views respectively that illustrate a step in joining the pai of elongate strips: shown in Figure 1 ;

[0040] Figures 1 LA and I I B are diagrammatic side and plan views respectively that illustrate a step in j aim ng the pair of elongate, strips, shown, in Figure 1 ;

[0041] Figure 12A is a diagramrnatte perspective view of a portion of pipe wound from the snip assembly shown in Figure 3A;

[0042] Figure ! 2B is a diagrammatic perspective view of the pipe shown in Figure 12 A lookin from inside the pipe;

[0043] Figure 13A is an isometric view f a joining apparatus for joining two elongate strips together; [004 J Figure 1.3B is a close up view of the portion indicated by circle A on Figure 13 A;

[0045] Figure 13C is a pian view of the joining apparatus shown in Figure 13B;

[0046 ] Figure .13D is a side vie of the pining apparatus shown to Figure .13B;

10047 ] Figure 13E is an end view of the j oining apparatus shown in Figure 13B;

[0048] Figure 14A is a perspecti ve view showing the pair of elongate strips shown in Figure 3A before they are j oined together;

10049] Figure 14B is an end view of one of the air of strips shown in Figure 1.4A;

[OOSO ^' I Figure 1.4C is a view of the end of the strip shown in Figure 14B, viewed from a direction ttOftoal (perpendicular) to the joining plane shown in: Figure 3 A, that is looking directly at the joining end surface; and

[00511 Figures I SA and 1.5 B shown alternative strips that also may he joined in .accordance.' with the iventioii.

DESCRIPTION OF EMBODIMEHTS

[0052] Referring now to Figure 1, there is shown a strip assembly 100 helically windable to form a pipe 200. such as the pipe 200 illustrated in Figures OA and OB. The strip assembly 100 includes a pair of joined elongate strips 10,10 ^* as is shown in Figure 1. Now referring to Figures 2A and 2B, it can be seen mat each strip includes a base 14, at least one longitudinal rib i 6 upstanding from the base 14 (in the eraboditnsrts Shown in Figures 1 to 2A, there are three ribs 16), a pair of spaced apart longitudinal parallel edges 12,18 and a joining end surface 30. A joining end surface- 30' is illustrated in Figures 3B and 3C- Each rib 16 has a centreline 17 that is perpendicular to the base 14 as illustrated in Figure 3A.

[0053] Referring now to Figure 1 A, it can be seen thai the strip also includes a joining end surface 30 and the strip 10 ^s includes the joining surface 30' . This joining end surface 30' lies wi thin joining plane 150, which is illustrated in Figure 3 A.. Figure 3C shows a joining end rib surface centreline 37 that is angled with respect to the centreline 17 that is perpendicular to the base: 14. The joining plane 150 intersects the parallel edges 32,18 to form an intersecting Hue 35, the intersecting line 35 forming an acute angle Θ of less than 85 degrees with one of the pair of edges. This is most clearly illustrated in Figure 3B, where the acute angle between the intersecting line 35 and the second edge 18 is apprajdrnaiei 45 degrees.

[ 0054] While irs use the strip assembly 1 0 will typicall be curved so zs to form a. helical pipe, when it is straight, the base lies hi ts" adjacent to a base plaiie 13 as is shown in Figure 3A. The johung plane 150 forms an angle β with respect to the base plane, the angle β being less than 85 degrees as is shown in. Figure 3D, This contrasts to a typical butt joint where the joining plane would coincide with the plane 130 illustrated in Figure 3 A. Plane 130 is both perpendicular to the base plan 15 and to the edges 12, 18.

[0053 ] The angled joint described above and shown in Ftgiire 1 , which .may be described at an angled scarf joint, provides a larger surface area than a straight, perpendicular cut would. This is most apparent when comparing the end view of Figure 14B with the view looking directly at the joining end surface 30' in Figure l4C. lt also ensures that the join line is angled so that when the strip passes though pinch rollers or is curved around guide rollers the join line is progressi vely squeezed or otherwise stressed. This assists in making the joined strips suitable fo machinery that winds strip helically to re-line pipes or conduits for instance.

[0056] The joint width, shown as ½ in Figure 3B, is substantial l _. y more than the strip width, shown as S in Figure 3B. Similarly the joint height, ¾, in Figure 3D, is substantially more than the strip height, shown as a in Figure 3D.

[00571 In one embodiment of the invention as illustrated in Figures 3A to 3D, the joining end surfaces 30, 30' have twice the surface area than would be achie ve by a simple butt j oint. This is because the intersect ing line 35 is angled at an angle Θ of 45 degrees (rather than 90 degrees) with respec t to the parallel edges and, the joining plane 150 forms aa angle β of 45 degrees (rather than 90 degrees) with respect to the base plane. This can be calculated as follows:

Increase in joint width: ½ S _w = !/sih θ = 1/sin 45° = ,1/0,7071 = 1.41.4 and

Increase in joint height: JH SH.~ I sin β - 1/sin 5" - 1/0.7071 ^~ 1.414

Then, the increase in joint area is increased by J _¾ /S _¾ . x = 1.414" = 2, that is, doubled.

[0058 ] In another embodiment of the invention, similar to that illustrated in Figures 3 A to 3D, the joining end surfaces 30, 30' have four tiroes the surface area than would be achieve by a simple butt joint. This is. because the intersecting fine 35 is angled at an angle Θ of 30 degrees (rather than 90 degrees) with respect to the parallel, edges and, the joining plane 150 forms; an angle β of 30 degrees (rather than 90 degrees) with respect to the base plane. This can be calculated as follows;

increase in joint width: J¾,-/5w - 1/sin Θ = 1/sin 3Θ° = 1/0.5 - 2 and Increase in joint height:. Jn/So *= i /sin \\ = l/sin 30" = 1/0.5 = ^: 2

en, the increase in j omi area is increased by J Sw x J H/SH = 2 ^* - 4„- that is, quadrupled. [ 00591 The additional joint area provides a significantl stronger j int

[0060] .Referring now to Figures I3A and i 3 B, a joining apparatus 300 for joining two strips to form a strip assembly 10 is shown. The joining apparatus 300 includes a bench top 310 supported b a {f me 12 sitting on wheels: 313. The wheels 31 allow the joining apparatus to he moved easily. The joining apparatus 300 also includes strip su port surfaces 320, 320'. The strip support surfaces sit above the bench, top 310.

[0061] The strip support surface 320 is connected to a floating support surface adjusting mechanism 322 which allows support surface 320 to "float" or move with respect to support surface 320' and the bench top 31 . The floating support surface adjusting mechanism 322 includes a hand wheel 325 most clearly shown in the enlarged view of Figure 13B. The hand wheel 325 is used to laterally move the strip support surface 320 away from and towards the fixed strip support surface 320' .

[0062] The bench top 310 also supports a tilting head saw 360, The saw 360 has a handle 370, The saw 360 is mounted on a rotating saw arm 350, which rotates about saw arm a is 350a. The rotating saw arm 350 is mounted to a rotating saw base 340, -which rotates about a saw base axis 340a. In this way, the saw can be rotated to create angled -mitre cuts, or scarf joints.

[0063] Figure 13C is a plan view of the joining apparatus 300 and Figures 13B and 1 E are side view and end views respectively.

1 064] A pipe can be helically wound from, the strip assembly 100 as described above to form a pipe, such as the pipe illustrated in Figures 12A and 12B, The ability to create the strip assembly 1.00 from two or more strips 10 and W allows large spools of strip to be created By providing long lengths of strip on a single spool, the efficiency of the on-site winding, process can be significantly improved.

[0065 ] Figures I5A and 15B shown alternative snips 3.0A and iOB that also may be joined in accordance with the invention. Other strips or profiles, not shown, may also be joined in accordance with the invention.

[0066] A method of joining a first strip 10 to a second strip 10', each strip including:: a base having first and second spaced-apart parallel longitudinal edges; and at least one longitudinal rib upstanding from the base will now be: described. [00671 A method of joining a first stri to a second stri includes the following steps:

(j) positioning an end portion 20 of the first strip 10 over an end portion 20' of the second strip Uf such that: the first longitudinal edge 12 of the first strip 10 overlaps and is substantially aligned wit the first longitudi n al edge 12' of the second strip 10', and the secon d longitudinal edge I of the first strip 10 overlaps and is substantially aliped witn the second longitudinal 18' edge of the second strip 10* ;

(2) cutting the overlapping end porti ons of the first and second strips to produce a pair of adjacent angled joining end surfaces 30, 30';

(3) treating at least one of the pair of joining end surfaces 30, 30; and

(4) pressing the pair of joining end surfaces 30, 30- against each other so as to create compression and holding the compression for a time period, the time period sufficient to create a bond,

thereby bonding the first strip .10 to the second strip 1.0\ This method is shown progressively in Figures 4A and 4B through to Figures 1 1 A and 1 1 B. Specifically,, step (1 ) above is shown in Figures 4A and 4JB and step (2) is shown in figures 5A and 5B and 6A and 6B. Ste (3), the treating step, is shown in Figures I OA and i B, with applicator 40 delivering an adhesive, or glue, to joining end surface 30. The pressing step (4) is illustrated in Figures .1 ί A and Ϊ IB .

10068 ) After the positioning, step (1) above* the strips can be held in positio by toggle clamps 330, 330' as is shown in Figures 1 A, 1 C, and 1.3D.

[0069] With the method described above, there are a number of options for the treating step. For instance, a glue in the form of a cyanoacrylate adhesive may be used. In that ease, die treating step includes applying a cyanoacrylate adhesive to one of the pair of joinin end surfaces, as is illustrated in Figures l.OA and 1.0B.

[0070] Another optio for the treating ste utilises a heating process. I that case, the treating step of Figures ί OA and 10B includes heating both of the pair of joining end surfaces (not illustrated). Such a heating process results: in welding, the pair of end surfaces,

[0071 ] The- period of time for holding the compression in step 4 above will vary, but when using a cyanoacrylate adhesive may be expected to be quite short - only a few minutes.

[0072] Additional steps of re-cutting and thereby re-forming the pair of joining end surfaces 30,30' while the base of the first strip i 0 is aligned with the base of the second strip 10" results in the transformation of the strips as they are shown in Figures 8A and SB to Figure 9 A and 9B-. This additional re-cutting step, if provided, occurs between the cutting step 2 and the treating step 3 described above, it has been found that the re-cutting step significantly improves the bond attainable between, the two- strips because the end joining surfaces are more accurately aligned. [00731 Referring to Figures 5 A and SB, an angled cut 395 in progress is shown. The cut is angled at angle Θ, as shown in Figure 5B and at an. angle p\ as is shown in Figure 5A.

[ 0074] The completed eot ^' iS: shown in Figures 6 A and 6B. The cut results in off cut or waste portions 22,22:' and retained end portions 21 , 1 '. These retained end portions are now alignable, as is shown in Figures 7 A and ?B. Once in this aligned condition, they can be brought together by movement of a floating: strip support surface 320 towards a fixed strip support surface 320', as is illustrated

progressively from Figures 7A and 7B to Figures 8A and SB.

[ 0075 ] Once in the position shown hi Figures 8 A and SB, w ere rough cut ends are held substantially adjacent, a second, more precise cut can be made at angles Θ and β so as to provide clean and closely aligned joining. end surfaces 30 and 30',

[0076] The floating strip support surface 320 is then moved away from the fixed strip support 320' into the position shown in Figures ISA and 10B. At this point, an applicator 40 can be used to apply an adhesive t the joining end surface 30.

[0077] The floating strip support, surface 320 is then moved back towards the fixed strip support surface 320' such that the retained end portion 21 pushes against th retained end portion 21 ' and the joining end surface 30 and 30' arc pressed against each other. The surface 30,30' are held against, each other for a minute or two until the adhesive has reached sufficient strength (the length of time required for thi step will depend on the formulation of the adhesive and various othe factors).

[0078] Where the treating step utilises a heating process (instead of a gluing process), the joining end surface 30: and 30* are pressed against .each.other while partially melted. The surfaces 30,30' are held against each other for a minute or two until the weld has reached sufficient strength (the length of time required for this step will depend on various factors).

[0079] The above-described method allows large spools of strip to be created from, multiple (2 or more) lengths of (extruded) strip. This reduces waste and improves efficiency of creating of large ca acity spools.

[0080] Throughout the specification and the claims that follow?, unless the context requires otherwise,; the words "comprise" and "include" and variations such as "comprising" and "including" will be understood to imply the inclusion of a stated integer or group of integers, but not the exclusion of an Other integer x group of integers. [00811 The reference to any prior art irt this specification is not, and should not be taken as, an acknowledgenient of an form of suggestion that such prior art forms part of Ac common general knowledge,

10082] It will be appreciated, by those skilled in the art that the invention is not restricted in its use to the particular application described. Neither is the present invention restricted, in its preferred embodiment with, regard to the particular elements and/or features described or depicted herein. It will be appreciated that the: invention is no t limited to the embodiment or embodiments disclosed, but is capable of nu merous rearrangements, modifications and substitutions without departing from the scope of the ϊηνεηίίαη. as: set forth and defined by the Following claims.

[0083] Please note that the following claims are ^■ provisional claims only, and arc provided as examples- of possible claims and are not intended to limit the scope of what may be claimed in any future: patent applications based o the present application. Integers may be added to or omitted from the example claims at a later date so as to further define or re-define the invention.