AU2013203971C1

AU2013203971C1 - A winding machine and winding cage for a helically wound pipe

Info

Publication number: AU2013203971C1
Application number: AU2013203971A
Authority: AU
Inventors: Paul CENTOFANTI; Roy Duncan
Original assignee: Sekisui Rib Loc Australia Pty Ltd
Current assignee: Sekisui Rib Loc Australia Pty Ltd
Priority date: 2012-03-22
Filing date: 2013-03-22
Publication date: 2016-07-21
Anticipated expiration: 2033-03-22
Also published as: EP2828065A4; EA201491660A1; NZ629912A; AU2013203982B2; NZ629904A; AU2013203971B2; EP2828066A4; AU2013203982A1; EP2828065A1; TW201418608A; AU2013203971A1; EA201491661A1; WO2013138869A1; EP2828066A1; TW201402305A; WO2013138868A1

Abstract

A winding cage for winding a helically wound pipe from an elongate ribbed strip having opposed joinable edge portions is disclosed. The winding cage includes: a curved primary frame, the curved primary frame describing a primary arc of at least 120 de grees; a strip guiding assembly disposed around and supported by the curved primary frame, the strip guiding assembly arranged to guide a strip around a helical path, the strip guiding assembly defining a strip path, the strip path forming at least a portion of a helix having a longitudinal axis; and a plurality of arms spread circumferentially around and extending from the curved primary frame in a direction having a component parallel to the longitudinal axis, the arms forming part of the strip guiding assembly and arranged to support respective guide sub-assemblies.

Description

A WINDING MACHINE AND WINDING CAGE FOR A HELICALLY WOUND PD?E

PRIORITY DOCUMENTS

[0001] The present application claims priority from:

Australian Provisional Patent Application No. 2012901 163 titled "A WINDING MACHINE AND WINDING CAGE FOR A HELICALLY WOUND PIPE" and filed on 22 March 2012; and

Australian Provisional Patent Application No. 2012901162 titled "A WINDING MACHINE AND WINDING CAGE FOR A HELICALLY WOUND PIPE" and filed on 22 March 2012.

The content of each of these applications is hereby incorporated by reference in their entirety.

TECHNICAL FIELD

[0002] The invention relates to an apparatus for lining pipes or conduits with a helically wound pipe. The invention relates in particular to winding machine for relining a conduit where the pipe is wound within the conduit.

BACKGROUND

[0003] The applicant has developed various technologies to allow trenchless pipe rehabilitation. The applicant's International Patent Application No. PCT/AU87/00069 titled "Method and Means for Lining and Overwrapping Conduits" described a method and means of lining conduits, pipes or tunnels. The method described in that patent included helically winding a strip into a pipe and holding the pipe at a selected diameter during placement within the pipe to be rehabilitated. The method described further included the step of applying pulling force to the newly helically wound pipe to cause the inter engaged edges of the strips forming the pipe to slip with respect with each other so as to increase the diameter of the pipe progressively until it engages the walls of the conduit to be relined.

[0004] The technology described above can be described as an expanding helically wound pipe technology. The expanding helically wound pipe technology involves positioning a winding cage underground within a host pipe as is described in the above mentioned International Patent Application No. PCT/AU87/00069. This often requires enlargement of the access area adjacent the pipe to be relined to accommodate the winding cage. Enlargement, or "chop-out", typically involves jack hammering concrete which takes considerable effort and time. [0005] Even where pipes are wound at a final diameter using a winding cage underground within a host pipe (without subsequently expanding the wound pipe), enlargement of the access area adjacent the pipe to be relined to accommodate the winding cage is often required.

[0006] It is an object of the present invention to overcome at least some of the problems outlined above or to at least offer the public a useful choice.

SUMMARY

[0007] According to a first aspect, there is provided a winding cage for winding a helically wound pipe from an elongate ribbed strip having opposed joinable edge portions, the winding cage including:

a curved primary frame, the curved primary frame describing a primary arc of at least 120 degrees; a strip guiding assembly disposed around and supported by the curved primary frame, the strip guiding assembly arranged to guide a strip around a helical path, the strip guiding assembly defining a strip path, the strip path forming at least a portion of a helix having a longitudinal axis; and

a plurality of arms spread circumferentially around and extending from the curved primary frame in a direction having a component parallel to the longitudinal axis, the arms forming part of the strip guiding assembly and arranged to support respective guide sub-assemblies.

[0008] In one embodiment the guide sub-assemblies include a plurality of guide rollers.

[0009] In one embodiment the curved primary frame extends into the strip path in a radially inwards direction but is positioned sufficiently longitudinally outside of the strip path so as not to block the strip path.

[0010] In one embodiment the arms function as cantilevers, transferring load imparted by the strip wholly or at least substantially to the curved primary frame.

[0011] In one embodiment the arms are orientated substantially perpendicular to the primary frame.

[0012] In one embodiment the curved primary frame includes a proximal curved member and a distal curved member, the proximal and distal curved members arranged parallel and spaced apart.

[0013] In one embodiment the winding cage includes a plurality of arm mounts, the arm mounts disposed between the proximal curved member and the distal curved member,

whereby the arms are mounted to the arm mounts. [0014] In one embodiment the arm mounts are moveable between at least two radial positions so as to adjust a diameter of the strip path.

[0015] According to a second aspect there is provided a winding cage for helically winding a pipe from a strip, the winding cage including:

a curved primary frame, the curved primary frame describing a primary arc of at least 120 degrees; a plurality of outer support members spread circumferentially around and extending longitudinally from the curved primary frame, the outer support members forming part of the strip guiding assembly, each outer support member supporting a set of rollers, each roller mounted to its respective outer support members so as to guide the strip along a strip path.

[0016] In one embodiment the winding cage includes at least three outer support members.

[0017] In one embodiment each outer support member supports a plurality of rollers.

[0018] In one embodiment curved primary frame extends into the strip path in a radially inwards direction but is positioned sufficiently longitudinally outside of the strip path so as not to block the strip path.

[001 ] In one embodiment the outer support members include cantilevered arms.

[0020] In one embodiment the arms are orientated substantially perpendicular to the primary frame.

[0021] . In one embodiment the curved primary frame includes a proximal curved member and a distal curved member, the proximal and distal curved members arranged parallel and spaced apart.

[0022] In one embodiment the winding cage includes a plurality of arm mounts, the arm mounts disposed between the proximal curved member and the distal curved member,

whereby the arms are mounted to the arm mounts.

[0023] In one embodiment the arm mounts are moveable between at least two radial positions so as to adjust a diameter of the strip path.

[0024] According to a third aspect there is provided a winding cage for helically winding a pipe from a strip, the winding cage including:

a curved primary frame, the curved primary frame describing a primary arc of at least 120 degrees; a strip guiding assembly disposed around and supported by the curved primary frame, the strip guiding assembly arranged to guide a strip around a helical path, the strip guiding assembly defining a strip path, the strip path forming a portion of a helix having a longitudinal axis; and a plurality of arms spread circumferentially around and extending longitudinally from the curved primary frame, each arm supporting a set of rollers, each roller having a separate roller shaft and roller shaft support mounted to its respective arm such that no part of each roller protrudes radially beyond its respective arm, the separate roller shafts and shaft supports spaced apart so as to provide rib-receiving channels between the rollers.

[0025] In one embodiment the curved primary frame extends into the strip path in a radially inwards direction but is positioned sufficiently longitudinally outside of the strip path so as not to block the strip path.

[0026] In one embodiment the arms function as cantilevers, transferring load imparted by the strip substantially to the curved primary frame.

[0027] In one embodiment the arms are orientated substantially perpendicular to the primary frame.

[0028] In one embodiment the curved primary frame includes a proximal curved member and a distal curved member, the proximal and distal curved members arranged parallel and spaced apart.

[0029] In one embodiment the winding cage includes a plurality of arm mounts, the arm mounts disposed between the proximal curved member and the distal curved member,

whereby the arms are mounted to the arm mounts.

[0030] In one embodiment the arm mounts are moveable between at least two radial positions so as to adjust a diameter of the strip path.

[0031] A detailed description of one or more embodiments of the invention is provided below along with accompanying Figures that illustrate by way of example the principles of the invention. While the invention is described in connection with such embodiments, it should be understood that the invention is not limited to any embodiment. On the contrary, the scope of the invention is limited only by the appended claims and the invention encompasses numerous alternatives, modifications and equivalents. For the purpose of example, numerous specific details are set forth in the following description in order to provide a thorough understanding of the present invention.

[0032] The present invention may be practiced according to the claims without some or all of these specific details. For the purpose of clarity, technical material that is known in the technical fields related to the invention has not been described in detail so that the present invention is not unnecessarily obscured. BRIEF DESCRIPTION OF DRAWINGS

[0033] Embodiments of the present invention will be discussed with reference to the accompanying drawings wherein:

[0034] Figure 1 shows a schematic cross-sectional view of an underground conduit being relined using a prior art winding machine.

[0035] Figure 2 is an isometric view of a winding machine that can be used in a conduit such as that shown in Figure 1.

[0036] Figures 3a and 3b are cross-sectional views of strip or profile used to helically wound pipe as shown in Figure 1.

[0037] Figure 4 is a similar view to Figure 1 but illustrates use of a winding machine according to the present invention.

[0038] Figure 5a is an isometric view of a winding machine according to the invention.

[0039] Figure 5b is a similar view to Figure 1 but shows a drive assembly removed so as to more clearly show a winding cage.

[0040] Figure 5c is a closeup isometric view of a portion of the winding machine shown in Figure 5a together with a portion of the newly wound pipe.

[0041] Figure 6 is a cross-sectional view showing the winding machine of Figure 5a within a conduit to be relined.

[0042] Figures 7 and 8 are enlarged isometric views of a portion of the winding machine shown in Figure 5a.

[0043] Figure 9a is a cross-sectional view of a roller 130 shown in Figure 5a.

[0044] Figure 9b is a cross-sectional view through lines 9b-9b shown in Figure 9a.

i

[0045] Figure 9c is a cross-sectional view through section lines 9c-9c shown in Figure 9a.

[0046] Figure 10 is a cross-sectional view of a cantilevered arm and associated circumferential support rollers shown in Figures 5a and 7. [0047] Figures 1 la and 1 lb are similar views to Figure 10 but is a cross-sectional view taken through a different cross-section.

[0048] Figure 12a is a view showing a portion of a strip guide sub-assembly of the machine of Figure 5a. ·

[0049] Figure 12b is a similar view to that of Figure 12a, but shows the strip guide sub-assembly being engaged by a strip leading edge.

[0050] Figure 13 is a view showing a further portion of a strip guide sub-assembly of the machine of Figure 5a.

[0051] Figures 14, 15 and 16 show an alternative strip guide sub-assembly.

[0052] Figure 17 is an isometric view of a winding machine similar to that shown in Figure 5a, but shows an alternative embodiment of the invention.

[0053] Figure 18 is a similar cross-sectional view to that shown in Figure 9a, but shows an alternative roller 130 to the roller shown in Figures 5a and 9a.

[0054] Figure 19 is a cross-sectional view of a cantilevered arm and associated circumferential support rollers shown in Figure 17.

[0055] Figure 20 shows the strip guide sub-assembly shown in Figures 17 and 19 in a plan view.

[0056] Figure 21 shows the strip guide sub-assembly shown in Figures 17 and 19 in a side view.

[0057] Figure 22 shows the strip guide sub-assembly of Figure 21 in a cross-sectional view through section lines B-B as shown in Figure 21.

DESCRIPTION OF EMBODIMENTS

[0058] Referring to Figures 1 and 2, it is known to reline conduits such as sewer or storm water conduits with helically wound pipe 9 using a pipe winding machine 50. The conduit or host pipe being relined may be of circular, oval, square or rectangular cross-section for instance. Some clearance is required between the wound pipe 9 and the host pipe 5 in order to allow the newly wound pipe 9 to move longitudinally with respect to the host pipe 5. The longitudinal movement is often facilitated by winding the pipe while the host pipe contains water as is illustrated in Figure 1. [0059] Irrespective of the shape of the host pipe, it is generally desirable to wind a new pipe with a cross- sectional area as close as possible to a cross-sectional area of the host pipe. Where winding new pipe into a host conditional pipe having a circular cross-section, it is generally desirable to minimise the distance between the outside diameter of the newly wound pipe and the inside diameter of the host pipe. This is the case irrespective of whether, subsequent to winding, the new pipe is to be expanded out to a larger diameter after the initial winding.

[0060] It is often necessary to enlarge the access area adjacent the pipe to be realigned to accommodate the winding cage 60 of the winding machine 50. The enlarged or "chop-out" area 6 is illustrated in Figure 1. The enlargement or chop-out typically evolves jackhammering concrete which takes considerable effort and time.

[0061] The extent of the chop-out required can more clearly be appreciated with reference to Figure 2. In Figure 2 the inside wall of the host pipe 5 is illustrated and the winding cage 60 is shown protruding through into the concrete. In practice, the arrangement shown in Figure 2 does not occur. Instead, the region of the conduit or host pipe 5 where the winding cage is to be positioned is enlarged as shown is Figure 1.

[0062] Turning now to Figures 3a and 3b, a composite strip useable with the winding machine illustrated in Figure 2 or the winding machine according to the invention of Figure 5a are shown. These strips (sometimes referred to as "profiles") include a base 12, a male edge 14, a female edge 18 and a plurality (in this case 3) of upstanding ribs 20. Each rib 20 is reinforced by a reinforcing strip 30, typically steel. The base 12 of the strip forms the inner surface of the wound pipe. Other profiles (not shown) may also be used with embodiments of the invention.

[0063] A drive assembly 80 or 160 of winding machines 50 and 100 respectively drive the strip 10 into a winding cage 60 or 1 10 respectively.

[0064] Figure 3a and 3b show the join between female edges 18 and male edges 14'. Various joining methods may be used. For instance, welding or gluing may be used. A further alternative is to provide male and female interlocking portions so as to provide a mechanical link between edges of the strip.

[0065] Figure 5a shows a winding machine according to an embodiment of the invention. As in Figure 2, a portion of the inside face of the host conduit 5 is illustrated. From Figure 5a and Figure 6 it is apparent that the winding cage 100 is compact, particularly at its lower half, eliminating the need for excavation or chop- out. This will be explained in further detail below.

[0066] The winding machine 100 illustrated in Figures 5a and 6 includes a drive assembly, or drive tray, 160 having a strip entrance 162 and a strip exit 168. The drive assembly 160 pulls strip, such as the strip 10 shown in Figures 3a and 3b, from a spool 40, typically positioned above ground as shown in Figures 1 and 4, towards the drive assembly 160 and pushes the strip 10 out of the drive assembly exit 168 tangentially into the winding cage 1 10.

[0067] Referring now to Figures 7 and 8, the exit 168 of the drive assembly 160 is shown more clearly. The exit of drive assembly 168 includes a pair of pinch rollers 170 and 175. The strip 10 has been omitted from Figures 5a, 7 and 8 for clarity. However, the strip 10 is shown in Figure 5c at a position approximately diametrically opposite from the exit 168 of the drive assembly 160.

[0068] From Figure 5c it can be seen that an upper roller 130 has a plurality of groves 132 arranged to receive the ribs 20 of the strip 10, 10'. A cross-sectional view of the roller 130 is shown in Figure 9a. The groves 132 provide both circumferential and lateral support to the strip 10. The rollers 130 and their supporting cages add significantly to the overall diameter of the winding machine 100. This is not always important for the upper portion of the machine but is often important for the lower part of the machine as is clearly seen in the cross-sectional view of Figure 6.

[0069] Now turning to Figure 5b it can be seen that the winding cage 1 10 includes a curved primary frame 200 at its lower end and a curved secondary frame 120 at its upper end. The curved primary frame 200 describes a primary arc "A" of at least 120°. With the embodiment shown, this arc exceeds 180°. For many applications, an arc of at least 210° will be required for the primary frame 200 to allow the winding of the largest possible diameter new pipe within a particular host pipe 5. In still further applications, the curved primary frame 200 may describe an arc of 360 ⁰ In such an application, the embodiment of the invention would not have the curved secondary frame 120. In other words, the primary frame 200 may describe a complete annulus.

[0070] From Figures 5a and 6 it can be seen that the winding cage includes a strip guiding assembly disposed around and supported by the curved primary frame 200. The strip guiding assembly comprises a plurality of arms 300 spread circumferentially around and extending longitudinally from the curved primary frame 200. The strip guiding assembly also includes guide sub assemblies 410 more clearly shown in Figure 5c and Figure 12a and 12b.

[0071] Referring to Figure 5c, it can be seen that the curved primary frame 200, comprising proximal portion 220 and distal portion to 270, extends into the strip path in a radial inwards direction, but is positioned sufficiently longitudinally so as not to block the strip path.

[0072] It can also be seen from Figure 5c that the arms 300 are cantilevered from the curved primary frame 200. By employing a cantilever design, a curved distal cage component is not required (or at least is not required for the lower part- of the machine). This assists in keeping the outside diameter of the primary frame 200 of the winding cage 110 to a minimum and therefore reduces the need for excavation or chop-out. [0073] Referring to Figure 5a and 5b, it can be seen that sixteen (16) cantilever arms 300 are provided, each arm supporting (7) strip guide sub-assemblies 410, 420, 430, 440, 450, 460 and 470. Each cantilevered arm 300 is mounted perpendicularly to the primary frame 200. This makes manufacture of the winding machine simpler than manufacturing winding cages of the type shown in Figure 2. This is because with winding cages of the type shown in Figure 2, each roller 70 must be mounted at an angle with respect to the winding cage 60 between a proximal frame 62 and a distal frame 66 so as to substantially match the helix angle of the pipe being wound. In contrast, the cantilevered arms 300 of the winding machine 100 shown in Figures 5a and 5b are simply mounted perpendicular to the primary frame 200 irrespective of the pipe diameter being wound and hence irrespective of the helix angle being wound.

[0074] The only adjustment necessary for different helix angles will now be explained with reference to Figure 5 a. The extent to which the end of the cantilevered arms 300 protrude from the proximal side 220 of the primary frame 200 is indicated by arrows X| , X2, X3 etc. The dimensions x_u \₂, 3 etc can be adjusted to suit the helix angle of the pipe being wound. In practice, assuming that the cantilevered arms 300 are manufactured in equal lengths, the dimensions from x_t through to X(₆ shown in Figures 5a and Figures 5b will progressively decrease as the cantilevered arms reach further in a distal direction into the pipe to be wound. As will be appreciated by those familiar with operating such winding machines, this adjustment is much easier than adjustments required for roller 70 in a winding cage such as that shown in Figure 2.

[0075] In other embodiments of the invention (not shown), the cantilevered arms may be mounted at an angle to suit the helix angle of the pipe to be wound. Referring now to Figures 5c, 7 and 8, mounting of the arm 300 to the primary frame 200 and adjustment of the arm 300 with respect to the primary frame 200 will now be described. A pair of arm fasteners 510 is provided for each cantilevered arm 300 as is shown in Figure 7. Each arm fastener 510 includes a tensioner 512 having a handle end 514 and a cam end 519. The cam end 519 is pivotally connected to a shaft 518, the ends of which can be seen in Figure 5c. The arm fasteners 510 are of a similar construction to the quick release axle mount systems commonly seen on bicycles. They allow for rapid installation, adjustment or removal of arms 300. In other embodiments of the invention, not shown, other fastener types, such as simple nuts and bolts for instance may be used.

[0076] The shaft 518 of the arm fastener 510 engage wedge blocks 520 as can be seen in Figure 5c. These wedge blocks 520 act against wedge shaped sides 301 and 302 of the cantilevered arms 300. The sides 301 and 302 are more clearly visible in Figure 13 and the wedge 520 is also shown in Figure 1 la.

[0077] The strip guide sub-assemblies 410, 420, 430, 440, 450, 460 and 470 will now be described in more detail with reference to Figures 10, 11 and 12. Referring first to Figure 10, it can be seen that circumferential rollers 414 are arranged to roll against the base 12 of the strip 10. Each roller 414 has a separate roller shaft 415 supported by a shaft support. With the embodiment of the invention illustrated in Figure 10, the shaft support comprises a pair of spaced apart legs 416. The legs form part of a bracket 418 as is shown in Figure 12a.

[0078] The separate roller shafts 415, 425, 435, 445, 455, 465, 475 and corresponding separate shaft supports 416, 426, 436, 446, 456, 466 and 476 are spaced apart so as to provide rib-receiving channels between the rollers 414, 424, 434, 444, 454, 464, 474 as can be seen in Figures 7, 8 and 10. This arrangement minimises the distance z illustrated in Figure 10 between the crowns 25 of the ribs 20 of the strip 10 and the host pipe 5. The reduction in the distance z compared to the distance z achieved with rollers 130 is clearly shown by comparing Figure 10 with Figure 9a. The circumferential support rollers 414, 424, 434, 444, 454, 464 and 474 act on the strip 10 so as to keep it curved to the required diameter. The rollers 414, 424, 434, 444, 454, 464 and 474 thus perform a similar function to the rollers 130 at mounted to the secondary or upper portion 120 of the winding machine. They do so in a much more radially compact _f arrangement however. In other embodiments of the invention, not shown, the same compact arrangement provided by the canter levered arms 300 and strip guides sub-assemblies 410, 420, 430, 440, 450, 460 and 470 may be provided for the upper portion of the winding machine in place of the upper portion 120 shown in the drawings.

[0079] Referring again to Figure 10, it can be seen that circumferential support rollers 444 and 474 is positioned radially outboard of the other support rollers 414, 424, 434, 454, and 464. This is to accommodate the female to male join between adjacent convolutions of the strip 10 and 10'.

[0080] Aside from the need to control the curvature of the strip 10 and hence the diameter of the pipe being wound, it is necessary to control the longitudinal position of the strip 10 as it is being wound. Often this is achieved by the use of grooves such as the grooves 132 within rollers 130 as shown in Figure 9a. The groves 132 act on the ribs 20. A problem with this arrangement is that the rollers 130 are required to have a certain diameter to provide walls 133 of grooves 132 to support the ribs 20 of the strip 10. This tends to again increase the required dimension z as shown in Figure 9a. In contrast, with the rib support arrangement of the invention illustrated in Figures 1 la and 1 lb, a very compact arrangement can be provided as will now be explained.

[0081] Figure 1 la shows six rib support rollers 610, 620, 630, 640, 650 and 660. These rollers rotate about an axes perpendicular to the arm 300. These rollers are supported by brackets. For instance, roller 610 is supported by a bracket 418 as shown in Figure 12a.

[0082] Figure 1 la shows rollers 610, 620, 630, 40, 650 and 660 between each rib 20. In other

embodiments of the invention, it may not be necessary to provide six rollers. For instance, alternate rollers may be omitted between groups of strip guide sub-assemblies 400 on adjacent cantilevered arms 300. [0083] Rollers 610 (and rollers 620, 630, 640, 650 and 660 as applicable) provide lateral support for the ribs 20. The rollers are preferably sized so that their diameters are smaller that the spacing between the ribs at the relevant locations so that only one side of each roller is engaged by a rib 20 at any one point in time.

[0084] Referring now to Figure 12b, when strip 10 is entering the winding cage 1 10, it is progressively curved radially inwards by strip guide sub assemblies 410. With the larger rollers at the upper half of the machine as shown in Figure 9a, the spacing of the rollers is such that the leading edge 27 of the strip base 12 contacts rollers 130 at a point or line such that the roller itself provides a lead in. With the smaller diameter rollers 414, 424, 434, 444, 454, 464 and 474 of Figures 12a and 12b however, very close spacing of the rollers would normally be required. Instead, with the embodiment invention shown, the circumferential spacing of these rollers can remain quite wide by the provision of a lead in 419 as shown in Figures 12a and 12b.

[0085] The drive assembly 160 forces the leading edge 27 of the strip 10 against the lead in 419 such that the leading edge 27 of the strip 10 is moved radially inwards as it slides up towards and then over roller 414 in the position shown in Figure 12b to the position shown in Figure 12a.

[0086] Figure 9b shows a roller 130 where the outside diameter of the roller and the depth of the grooves 132 are such that the roller 130 engages with the inside of the base 12 of the strip 10. As can be seen in Figure 9a there is some clearance between the crowns of the ribs 20 and the valleys 134 of the roller 130.

[0087] Figure 9c is a cross-sectional view through section lines Figure 9c-9c on Figure 9a showing the engagement between'the strip 12 and the roller 130. There is no contact between the valley of the roller 134 and the rib crown 25.

[0088] As should be clear from the above description, there is a significant difference between the rollers 130 at the upper end of the winding cage 110 and the strip guide sub-assemblies 410 through to 470 at the lower portion of the winding cage 110. In particular, with the upper rollers 130, a single roller performs two functions. It performs the function of controlling the radial diameter of the pipe 9 being wound while at the same time controlling the lateral position of the strip as it is wound (or longitudinal position relative to the host pipe). In contrast, with the strip guide sub assemblies 410 through to 470 at the lower portion of the winding cage 110, the functions of controlling of the radial diameter of the pipe and controlling the lateral position and radial movement of the strip is separated by using, on the one hand, a set of circumferential support rollers 424, 434 etc through to 474 and on the other hand a set of rib support rollers 610, 620, 630, 640, 650 and 660. The separation of the function of the rollers together with the orientation of the axes about which the rib support rollers 610, 620, 630, 640, 50 and 660 rotate provides design flexibility and assists in minimizing the overall diameter of the winding cage 110. [0089] Figures 14, 15 and 16 show an alternative strip guide sub-assembly 410' to the sub-assembly 410 shown in Figure 12b. With strip guide sub-assembly 410', a roller assembly 700 performs the function of the rollers 610 and 414 providing support both against lateral and radial movement. A locking shaft 492 and lock nut 493 are provided to lock the strip guide sub-assembly 410' to the arms 300. Figure 17 is an isometric view of a winding machine similar to that shown in Figure 5a, but using alternative strip guide subassemblies of the type shown in Figures 14 to 16 and 20 to 22.

[0090] With the alternative strip guide sub-assemblies of the type shown in Figures 14 to 16 and 20 to 22, the rollers 700 and their supporting brackets 418 are shaped such that there is clearance for the crown of the joint 39. This provides an advantage over the roller 130 shown in Figures 9a and 18 where smaller diameter portions are required to accommodate the crown of the joint 39.

[0091] Figures 1 la and 1 lb show a primary frame arm mount 230. The arm mounts 230 are disposed between the proximal curved member 220 and the distal curved member 270 and are movable to allow adjustment between at least two radial positions so as to adjust a diameter of the strip path. A radially extended position for winding larger diameter pipes is shown in Figure 11 b.

[0092] In a further alternative embodiment of the invention, not shown, the groups or strip guide assemblies 400 and/or the strip guide sub-assemblies 410, 420, 430, 440, 450, 460 and 470 may employ low friction guides instead of rollers.

[0093] 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 not limited to the embodiment or embodiments disclosed, but is capable of numerous rearrangements, modifications and substitutions without departing from the scope of the invention as set forth and defined by the following claims.

Claims

1. A winding cage for winding a helically wound pipe from an elongate ribbed strip having opposed joinable edge portions, the winding cage including:

2. The winding cage as claimed in claim 1 wherein the guide sub-assemblies include a plurality of guide rollers.

3. The winding cage as claimed in claim 2 wherein the curved primary frame extends into the strip path in a radially inwards direction but is positioned sufficiently longitudinally outside of the strip path so as not to block the strip path.

4. The winding cage as claimed in claim 2 wherein the arms function as cantilevers, transferring load imparted by the strip wholly or at least substantially to the curved primary frame.

5. The winding cage as claimed in either one of claims 3 or 4 wherein the arms are orientated substantially perpendicular to the primary frame.

6. The winding cage as claimed in claim 5 wherein the curved primary frame includes a proximal curved member and a distal curved member, the proximal and distal curved members arranged parallel and spaced apart.

7. The winding cage as claimed in claim 6 including a plurality of arm mounts, the arm mounts disposed between the proximal curved member and the distal curved member,

whereby the arms are mounted to the arm mounts.

8. The winding cage as claimed in claim 7 wherein the arm mounts are moveable between at least two radial positions so as to adjust a diameter of the strip path.

9. A winding cage for helically winding a pipe from a strip, the winding cage including: a curved primary frame, the curved primary frame describing a primary arc of at least 120 degrees; a plurality of outer support members spread circumferentially around and extending longitudinally from the curved primary frame, the outer support members forming part of the strip guiding assembly, each outer support member supporting a set of rollers, each roller mounted to its respective outer support members so as to guide the strip along a strip path.

10. The winding cage as claimed in the preceding claim including at least three outer support members.

11. The winding cage as claimed in the preceding claim wherein each outer support member supports a plurality of rollers.

12. The winding cage as claimed in claim 11 wherein the curved primary frame extends into the strip path in a radially inwards direction but is positioned sufficiently longitudinally outside of the strip path so as not to block the strip path.

13. The winding cage as claimed in claim 11 wherein the outer support members include cantilevered arms.

14. The winding cage as claimed in either one of claims 12 or 13 wherein the arms are orientated

substantially perpendicular to the primary frame.

15. The winding cage as claimed in the preceding claim wherein the curved primary frame includes a

proximal curved member and a distal curved member, the proximal and distal curved members arranged parallel and spaced apart.

16. The winding cage as claimed in the preceding claim including a plurality of arm mounts, the arm

mounts disposed between the proximal curved member and the distal curved member,

whereby the arms are mounted to the arm mounts.

17. The winding cage as claimed in the preceding claim wherein the arm mounts are moveable between at least two radial positions so as to adjust a diameter of the strip path.

18. A winding cage for helically winding a pipe from a strip, the winding cage including:

19. The winding cage as claimed in claim 18 wherein the curved primary frame extends into the strip path in a radially inwards direction but is positioned sufficiently longitudinally outside of the strip path so as not to block the strip path.

20. The winding cage as claimed in claim 18 wherein the arms function as cantilevers, transferring load imparted by the strip substantially to the curved primary frame.

21. The winding cage as claimed in claim 20 wherein the arms are orientated substantially perpendicular to the primary frame.

22. The winding cage as claimed in the preceding claim wherein the curved primary frame includes a proximal curved member and a distal curved member, the proximal and distal curved members arranged parallel and spaced apart.

23. The winding cage as claimed in the preceding claim including a plurality of arm mounts, the arm

whereby the arms are mounted to the arm mounts.

24. The winding cage as claimed in the preceding claim wherein the arm mounts are moveable between at least two radial positions so as to adjust a diameter of the strip path.