Apparatus and method for the controlled internal lining of conduits

Abstract

The present invention provides an apparatus and method for the controlled internal lining of conduits requiring rehabilitation. In particular, the apparatus and method enables the speed at which repair pipe liner is fed into the conduit to be appropriately synchronized with the speed at which wire is simultaneously removed from inside the repair pipe, thereby ensuring that the length of a cone shape formed in the expanding pipe is maintained substantially between an upper and lower cone length limit that enables expansion of the repair pipe up to a final diameter. One or more outputs are generated including a speed at which the strip material should be fed in, or a speed at which wire should be removed during expansion to ensure that the cone shape length is maintained substantially within the upper and lower cone length limits.

Description

APPARATUS AND METHOD FOR THE CONTROLLED INTERNAL LINING OF CONDUITSFIELD OF THE INVENTION

[0001] The present invention relates to an apparatus and method for the controlled internal lining of conduits requiring rehabilitation (including underground sewer pipes, tunnels, etc). In particular, the apparatus and method enables the speed at which repair pipe liner is fed into the conduit to be appropriately synchronized with the speed at which wire is simultaneously removed from inside the repair pipe, thereby enabling expansion of the repair pipe in a controlled manner.BACKGROUND OF THE INVENTION

[0002] The term “conduit” is used in the present specification to reflect any type of channel for conveying water or other fluid, and includes within its scope enclosed pipes and tubes requiring rehabilitation. Throughout this specification, the terms “conduit” and “pipe” may be used interchangeably, although it is to be understood that use of the word “pipe” is not intended to exclude any other type of conduit.

[0003] When a conduit (10) such as a sewer pipe (typically made of clay or concrete or cast-iron) becomes in need of repair, a tube of plastic (12) of a diameter smaller than the corroded or damaged part of the conduit (10) is placed or inserted into position to cover at least the damaged areas. There are several ways in which this has been achieved in the past, including through use of the pipe lining technology shown in Figures 1 to 6. This prior art technology involves a winding machine (14) that causes strip plastic material (16) (also known as “profile”, “web” or “strip”) having male (18) and female (20) locking edges to be helically wound into convolutions and edges of adjacent profile material pressed (22) whilst being fed into a host conduit (10) requiring rehabilitation. The pressing force (22) causes the overlapping edges (18 / 20) to interlock and form the convolutions, with male locks (typically in the form of longitudinal extruded ribs) (24) and female locks (typically in the form of longitudinal extruded channels or receptacles each comprising a pocket and jaws for engaging the male lock) (26) extending along edges of adjacent profile material (16) mechanically locking to form a helical pipe (12) that fits inside thehost conduit (10). In this way, the inserted pipe (12) acts as a repair pipe (also referred to herein as a “liner”).

[0004] This is usually achieved by having an operator (not shown) of the machine (14) positioned down a first man hole, a second operator (not shown) positioned down a second man hole, and the pipe liner (16) being fed from the first man hole through to the second man hole. The prior art machine (14) includes a drive tray (not shown) for feeding in the strip (16) and a cage (not shown) which is used to wind the plastic strip (16) in a helical pattern, the cage including rollers which force the overlapping male (18) and female (20) edges of adjacent strips together to mechanically lock each male lock (24) inside each corresponding female lock (26) in order to form the helical pipe (12).

[0005] A minimum threshold torque (referred to as “wind-in torque” or “wind-in pressure”) needs to be applied by the machine (14) when helically winding in the strip material to cause the male (24) and female (26) locks to interlock and form convolutions of the repair Pipe (12).

[0006] Since the diameter of the host conduit (10) is greater than the diameter of the inserted pipe (12), an annular space (28) is formed there between. This space (28) was traditionally filled using cementitious grout. However, filling the space (28) with grout is expensive and can give rise to a number of additional problems. Accordingly, to avoid or at least minimize the annular space formed between the inserted pipe (12) and the host conduit (10), the diameter of the inserted repair pipe is expanded. In this regard, the overlapping male (18) and female (20) locking edges of the strip material (16) engage by a controllable slidable fit between the male (24) and female (26) locks associated therewith. This allows the repair pipe (12) to be maintained at a selected diameter while positioning it in the host conduit (10), and for the diameter to subsequently change during an expansion stage, by causing the inter-engaged overlapping edges of the strip (16) forming the repair pipe (12) to slide one relative to the other. In other words, the repair pipe (12) is allowed to expand within the host conduit (10) being lined to a larger diameter in order to engage the wall of the conduit (10) or at least expand to a diameter that reduces the annular space (28).

[0007] In one known implementation, the strip material (16) includes a primary locking means which in the prior art embodiment shown in Figures 1 -6 involves a first set of male(24A) and female locks (26A) configured to engage, a secondary (sacrificial) locking means which involves an adjacent second set of male (24B) and female locks (26B) also configured to engage, and a slip control member (30). In other words, extending along a first longitudinal edge (18) of the strip material (16) are two male locks (24A, 24B) associated with the primary and secondary locking portions respectively, and extending along the second longitudinal edge (20) of the strip material (16) are two corresponding female locks (26A, 26B) which are also associated with the primary and secondary locking portions respectively. As mentioned, the secondary (sacrificial) locking portion is positioned closer to the edge of the strip (16). Accordingly, when the male longitudinal edge (18) of one convolution is pressed (22) against an overlapping female longitudinal edge (20) of an adjacent convolution, the male locks (24) are inserted into and thereby engage the corresponding female locks (26). Each male lock (24) includes a stem (32) and a head (34) which facilitates the engagement with the correspondingly shaped female lock (26). The sacrificial lock may also include an adhesive such as silicone glue to prevent the inter-engaged overlapping edges (18 / 20) from sliding relative to one another during formation of the repair pipe (12) inside the host conduit (10).

[0008] The slip control member (30) is usually in the form of a serated, roughened or multi-strand wire that is wound into a groove (35) positioned between the primary and secondary (sacrificial) locking portions. The wire (30) is configured to be progressively pulled out of position, as shown most clearly in Figure 3, in order to sever the secondary (sacrificial) locking means, ie. cut through the stem (32) of the male lock (24B) associated therewith such that the head (34) of the male lock (24B) remains inside the female lock (26B) of the secondary locking means. By severing the sacrificial lock, the two edges (18 / 20) become free to slide one in relative motion to the other, as shown in Figure 5.

[0009] The strip material (16) further includes a base (36) which forms the inner surface of the wound pipe (12), and a series of larger upstanding Tees (38) each comprising a Tee stem (39) and Tee head (40) which provide rigidity to the pipe (12).

[0010] The helically formed pipe (12) is maintained at the required diameter during the initial winding by way of the mechanical engagement between the male locks (24) and female locks (26) associated with each of the primary and secondary locking means, and by means of pre-applied adhesive in the sacrificial lock. The adhesive (not shown) is typically applied to each longitudinal female lock (26B) in order to lock and preventrotation between the overlapping edges (18 / 20) of repair pipe (12) prior to the expansion stage, and lubricant (not shown) is typically used in the primary lock to facilitate relative sliding between the male lock (24A) and associated female lock (26A) during expansion (ie. after the wire has been pulled out and the sacrificial lock is severed). The lubricant also serves to seal the repair pipe (12) in its expanded state based on the lubricant eventually hardening (which typically occurs within approximately 48 hours) and thereby reinforcing the engagement between male lock (24A) and female lock (26A) in the primary lock.

[0011] The mechanical engagement between the male (24B) and female (26B) locks of the sacrificial lock, along with the use of glue, ensures that convolutions of the repair pipe (12) will not slip prior to expansion (provided a threshold (maximum) amount of torque applied when helically winding in the strip material is not exceeded). This threshold torque is referred to as “holding torque” or “holding pressure”. The wire (30) is helically fed through the machine (14) at the same rate as profile (16), and during pressing (22) of the overlapping locking edges (18 / 20), the wire (30) is locked inside a helical groove positioned between the two female locks (26A, 26B) associated with the first and second lock.

[0012] The expansion stage involves increasing the diameter of the newly created internal liner (12) after it has been fed all the way through the host conduit (10). As previously described, upon formation of the repair pipe (12), the diameter of the repair pipe (12) is such that there is a gap (28) between its outer diameter and the internal diameter of the host conduit (10). In order to achieve expansion up to the internal diameter of the host pipe (10) or some other diameter, repair pipe (12) is fixed at its distal end and whilst strip material continues to be fed in, the wire (30) is removed (i.e. de-wound) from one end to the other end of the inside of the formed pipe (12), thereby progressively breaking the sacrificial lock at the stem (32) of the male lock (24B) thereof.

[0013] The portion of pipe (12) that is yet to expand (ie. still has wire (30) attached) is the portion that transmits torque. The minimum torque required to wind in profile (16) during the pipe expansion process and cause the second lock to slip and rotate after wire (30) has been removed is known as the “expansion torque” or “expansion pressure”. During the expansion stage, and in particular in the portion that is yet to have wire removed, the expansion torque should be maintained such that it continues not to exceedthe previously described holding torque, i.e. should not exceed an amount of torque that will cause the sacrificial lock of unexpanded pipe (12) to slip. In the portion of pipe that has had the sacrificial lock severed, the expansion torque will be greater than the holding torque which is what allows slipping and therefore expansion to occur up to a final diameter.

[0014] Accordingly, once the repair pipe (12) has been created by being fed from one man-hole to the other and after the distal end of the repair pipe (12) is fixed, the next step is to expand the repair pipe (12) by progressively removing wire (30) associated with mating helically wound edges (18 / 20) of the plastic strip at the same time as further profile (16) is added, which progressively breaks the sacrificial lock. The addition of profile (16) imparts a rotational torque on the pipe liner (12) and if the applied rotational torque exceeds the minimum torque required to cause the primary lock to slip, the diameter of the repair pipe (12) will expand. Expansion commences at the most distal end of the repair pipe (12) until the pipe (12) reaches a final diameter. The expansion will progressively occur in a direction back towards the first manhole (108) end as more wire (30) is helically removed and profile (16) added.

[0015] Accordingly, expansion is achieved by first fixing and thereby stopping the turning of the entire pipe (12) at the second man hole end, and then continuing to feed strip liner (16) through the machine. The path of least resistance is for the pipe (12) to start to rotationally slide at the fixed end and expand, progressively increasing in size from the second man hole end back to the first man hole end.

[0016] During this process, a cone shape (42) is formed along the repair pipe (12) which is defined by a distance between the fully expanded section of pipe (ie. where the repair pipe (12) contacts the internal surface of the host pipe (10)) and the point at which the repair pipe (12) still has wire (30) attached and hence is yet to be expanded. This cone shaped section (42) of pipe which is currently undergoing expansion moves along the repair pipe (12) back towards the first man hole end as wire (30) is progressively removed. In other words, the cone shape (40) is defined by the distance between where the liner (12) is fully expanded and where the wire (30) is currently being removed from within the Pipe (12).

[0017] In order to maintain an appropriate and consistent cone length, a high level of operator skill is currently required to ensure that the correct ratio is maintained between the rate at which profile (16) is fed in (during the expansion process) versus the rate at which wire (30) is pulled out to break the sacrificial lock. Maintaining the correct ratio ensures that the cone length remains relatively consistent throughout the expansion process which is important because if wire (30) is pulled out too slowly, the repair pipe (12) may fail (since the cone distance will decrease and potentially reach a critical cone length). On the other hand, if the wire (30) is pulled out too quickly, this will result in a longer cone length, and the pipe liner (12) may not fully expand in this scenario. The ideal cone length will typically include approximately 5 to 25 convolutions (helical windings) of strip material (16) along the cone length depending on factors including the expansion amount, the design of the profile, the lubricating properties of the silicone, and the design of the equipment.

[0018] In order to allow an operator to visually identify the number of convolutions inside the cone and to control and maintain the speed of material (16) being fed into the host conduit (10) and the speed of removal of wire (30) during the expansion stage, a camera (not shown) is typically fed through the inside of the repair pipe (12). The camera transmits a wired or wireless signal to a display screen which is accessible by the operator, and thereby provides the operator with a view inside the repair pipe (12) at the location of the camera (in particular, at the location of the cone). The speed at which strip liner (16) is fed in and the speed at which wire (30) is pulled out is manually controlled by the operator who is required to manually alter speed dials to ensure the optimum ratio is maintained throughout the expansion process based solely on visual internal inspection of the cone.

[0019] As described above, greater than approximately 25 wraps will result in the pipe (12) not being fully expanded, and fewer than approximately 5 wraps may result in pipe failure. The problem with current techniques is that the operator’s vision is often impaired since the process is camera dependent, and a significant stress burden is placed on the operator since problems which may occur during the process can be very costly particularly if the pipe liner has to be completely removed and re-installed as a result of operator error.

[0020] The present invention seeks to mitigate the problems discussed herein, or at least provide an alternative solution.

[0021] The reference to any prior art in this specification is not, and should not be taken as, an acknowledgement or any suggestion, that the prior art forms part of the common general knowledge.SUMMARY OF THE INVENTION

[0022] In one aspect, the present invention provides an apparatus for controlling the internal lining of a conduit requiring rehabilitation, the apparatus including: a means of causing, during a repair pipe formation process, strip material having a male and female locking edge to be helically wound such that male and female locking edges interlock to form a repair pipe that is fed into the conduit requiring rehabilitation, the interlocking male and female edges including a sacrificial lock; a means of simultaneously feeding an amount of wire that substantially corresponds with the amount of strip material being fed in to form the repair pipe such that the resultant repair pipe includes a strip of helically wound wire along its length that is removable from the inside of the repair pipe; a means of progressively removing, during a subsequent repair pipe expansion process which seeks to increase the diameter of the repair pipe to a final diameter inside the conduit, the wire from inside of the repair pipe from a distal to a proximal end thereof at the same time as additional strip material is being fed in to thereby cause the wire to progressively sever the sacrificial lock which causes progressive expansion of the repair pipe from the distal to the proximal end, wherein during the expansion process a cone shape is formed in the repair pipe between the section of pipe from which wire is yet to be removed and the section of pipe that has fully expanded inside the conduit; and a control means operable to ensure that the length of the cone shape is maintained substantially between an upper and lower cone length limit that enables expansion of the repair pipe up to the final diameter, including by generating an output according to one or more dimensional attributes of the repair pipe prior to expansion, the diameter of the conduit, and the upper and lower cone length limits, the output reflecting one or more of: a speed at which the strip material should be fed in during the repair pipe expansion process to ensure that the length of the cone shape is maintained substantially within the upper and lower cone length limits, and a speed at which the wire should be removed during the repair pipe expansion process to ensure that the length of the cone shape is maintained substantially within the upper and lower cone length.

[0023] In an embodiment, a cone length set point representing a cone length value between the upper and lower cone length limits is used by the control means to generate said output.

[0024] In an embodiment, the diameter of the conduit used by the control means to generate said output includes one or more of: a nominal diameter of the conduit requiring rehabilitation (eg. 600mm), an actual diameter of the conduit requiring rehabilitation (eg. 605mm), and an actual diameter of the conduit taking into account diameter changes along the length of the conduit requiring rehabilitation (eg. based on laser profiling of the interior of the host conduit which indicates the progressive diameter which may change along the length of the conduit).

[0025] In an embodiment, the one or more dimensional attributes of the repair pipe prior to expansion, used by the control means to generate said output, includes at least the outer diameter of the repair pipe prior to expansion.

[0026] In an embodiment, the means of causing strip material to be helically wound to form the repair pipe is a winding machine that includes a winding cage that causes the strip material to be helically wound and for the male and female locking edges to interlock, wherein the outer diameter of the formed repair pipe prior to expansion is substantially equal to the internal diameter of the winding cage.

[0027] In an embodiment, the strip material includes a base which forms the internal surface of the formed repair pipe, and a series of upstanding structural tees each comprising a stem and head for providing rigidity to the pipe.

[0028] In an embodiment, the one or more dimensional attributes of the repair pipe used by the control means to generate the output further includes one or more of: a width (also referred to herein as pitch) of the strip material used to form the repair pipe, a height of the upstanding tees, anda neutral axis position of the repair pipe which represents an axis that extends cross-sectionally through the strip material in a direction parallel to the base thereof, at a location that is neither in compression nor tension during formation of the repair pipe.

[0029] In an embodiment, the width (pitch) is a measurement of the distance between a male lock associated with the male locking edge of the strip material and a corresponding female lock associated with the female locking edge of the strip material.

[0030] In an embodiment, an actual amount (eg. length) of strip material added and the speed at which strip material is added is determined based on measuring the speed at which wire is being fed in which substantially corresponds with the speed at which strip material is being fed in.

[0031] In an embodiment, the speed of wire being fed in is measured using a rotary wire encoder.

[0032] In an embodiment, the control means is configured to detect when the determined actual amount (eg. length) of strip material being added and the speed at which strip material is being fed in corresponds with the previously determined speed at which the strip material should be fed in during the repair pipe expansion process to ensure that the length of the cone shape is maintained substantially between the upper and lower cone length limits. In the event that there is a discrepancy, the control means may generate an output reflecting the extent to which to adjust the speed at which strip material is being fed in to address the discrepancy.

[0033] In an alternative embodiment, an actual amount (eg. length) and speed at which wire is being removed during the pipe expansion process is determined based on measuring the speed at which wire is being removed.

[0034] In an embodiment, the speed of wire removal is measured using a rotary wire encoder.

[0035] In an embodiment, the control means is configured to detect that the determined actual amount and speed of wire removal corresponds with the previously determined speed at which the wire should be removed during the repair pipe expansion process to ensure that the length of the cone shape is maintained substantially between the uppersand lower cone length limits. In the event that there is a discrepancy, the control means may generate an output reflecting the extent to which to adjust the speed at which wire is being removed to address the discrepancy.

[0036] In an embodiment, the control means calculates the speed that wire should be removed and / or the speed that profile should be added, to ensure the length of the cone shape is maintained substantially between the upper and lower cone length limits, according to the following general relationship:Wire Speed Host Pipe DiameterProfile Speed Host Pipe Diameter — Cage Diameter

[0037] In an embodiment, when the amount of wire that is removed is more than the amount of wire that was originally added (eg. due to stretching of the wire during removal, as the wire severs the sacrificial lock), or the amount of wire added is not the same as the amount of strip material added (eg. if the profile stretches when formed into a pipe), a correction factor is automatically applied to the above formula.

[0038] In an embodiment, the strip material includes two sets of male and female locks, wherein one set represents the sacrificial lock.

[0039] In an embodiment, the control means is operable to generate additional output(s) including one or more of: the actual cone length during the repair pipe expansion process, the location of the wire representing the point along the repair pipe at which the wire is cutting the sacrificial lock (eg. the wire is at 53m along the pipe), the location at which the repair pipe has fully expanded (eg. 51 metres of pipe has fully expanded), and the length of the repair pipe which has been formed during the pipe formation process (ie. the length of pipe made).

[0040] In an embodiment, a cumulative cone length is determined according to a measurement of the actual cone length during the repair pipe expansion process, andwhen the cumulative cone length is determined as being different to the cone length set point, the control means is operable to generate an output to alter the speed at which wire is being removed and / or strip material is being fed in during the pipe expansion process to cause the actual cone length to correspond with the cone length set point.

[0041] For example, an operator and / or the winding machine (106) may receive an instruction to cause wire removal to occur at a speed of 50m / min to maintain a constant cone length of 15 wraps according to a cone length set point of 15 wraps. If the actual speed was set at say 49 m / min, the cone length would reduce. For example, after 1 minute the actual cone length may reduce from 15 to 14 wraps, after 2 minutes to 13 wraps, after 3 mins to 12 wraps, etc.

[0042] Now if the operator adjusts the actual wire speed back to 50 m / min, the cone length would remain at 12 wraps which is not the cone length set point. Accordingly, the operator would be required to adjust the wire speed further in order to compensate, which can be achieved in a number of ways. For example, the operator may be directed to adjust the wire removal speed to say 51 m / min for 3 mins to get back to a cone length of 15 wraps. In another example, the operator may be directed to adjust the wire removal speed to 53m / min for 1 min. In a further example, the operator may be directed to adjust the wire removal speed to 100m / min for the required number of seconds.

[0043] According to a further aspect, the present invention provides a method for controlling the internal lining of a conduit requiring rehabilitation, the method including: causing, during a repair pipe formation process, strip material having a male and female locking edge to be helically wound such that male and female locking edges interlock to form a repair pipe that is fed into the conduit requiring rehabilitation, the interlocking male and female edges including a sacrificial lock; simultaneously feeding an amount of wire that substantially corresponds with the amount of strip material being fed in to form the repair pipe such that the resultant repair pipe includes a strip of helically wound wire along its length that is removable from the inside of the repair pipe; progressively removing, during a subsequent repair pipe expansion process which seeks to increase the diameter of the repair pipe to a final diameter inside theconduit, the wire from inside of the repair pipe from a distal to a proximal end thereof at the same time as additional strip material is being fed in to thereby cause the wire to progressively sever the sacrificial lock which causes progressive expansion of the repair pipe from the distal to the proximal end, wherein during the expansion process a cone shape is formed in the repair pipe between the section of pipe from which wire is yet to be removed and the section of pipe that has expanded inside the conduit; and generating, according to one or more dimensional attributes of the repair pipe prior to expansion, the diameter of the conduit, and upper and lower cone length limits that enable expansion of the repair pipe up to the final diameter, an output that ensures that the length of the cone shape is maintained substantially within the upper and lower cone length limits, the output reflecting one or more of: a speed at which the strip material should be fed in during the repair pipe expansion process to ensure that the length of the cone shape is maintained substantially within the upper and lower cone length limits, and a speed at which the wire should be removed during the repair pipe expansion process to ensure that the length of the cone shape is maintained substantially within the upper and lower cone length limits.

[0044] In an embodiment, the output(s) include one or more: automatic instructions transmitted to the apparatus to cause the apparatus to operate in accordance with the one or more automatic instructions, or instructions transmitted to a device associated with a human operator to enable the operator to view the one or more instructions and cause the apparatus to operate in accordance with the one or more instructions.BRIEF DESCRIPTION OF THE DRAWINGS

[0045] Embodiments of the invention will now be described in further detail with reference to the accompanying figures in which:

[0046] Figure 1 illustrates a perspective cutaway view of a prior art apparatus and method used to feed strip material having male and female locking edges into a host conduit requiring rehabilitation, the strip material being helically wound and pressed in a configuration that causes overlapping male and female edges to engage and form a repair pipe.

[0047] Figure 2 illustrates an enlarged perspective cutaway view of two overlapping male and female locking edges associated with the prior art apparatus and method of Figure 1 during the process of helically winding and pressing the strip material to form the repair pipe.

[0048] Figure 3 illustrates a further perspective cutaway view of a repair pipe formed by the prior art apparatus and method of Figure 1 , the repair pipe undergoing expansion according to the progressive removal of wire from within the repair pipe which severs a sacrificial lock preventing the male and female edges from rotationally sliding and expanding, thereby causing the repair pipe to rotationally slide and expand inside the host conduit.

[0049] Figure 4 illustrates an enlarged perspective cutaway view of two overlapping male and female locking edges associated with the prior art apparatus and method of Figure 1 during severing of the sacrificial lock based on removal of the wire.

[0050] Figure 5 illustrates an enlarged perspective cutaway view of two overlapping male and female locking edges associated with the prior art apparatus and method of Figure 1 after severing of the sacrificial lock based on removal of the wire, thereby causing the overlapping edges to rotationally slide and expand.

[0051] Figure 6 illustrates a further perspective cutaway view of a repair pipe formed by the prior art apparatus and method of Figure 1 , the repair pipe undergoing expansion according to the progressive removal of wire from within the repair pipe and forming acone shape between the fully expanded section of pipe and the point at which the repair pipe still has wire attached and is yet to be expanded.

[0052] Figure 7 illustrates a cross sectional view of strip material according to an embodiment of the present invention in which the width (pitch) and neutral axis of the strip are identified.

[0053] Figure 8 illustrates a perspective cutaway view of an apparatus and method for the controlled internal lining of conduits using the strip material of Figure 7 according to an embodiment of the present invention.

[0054] Figure 9 illustrates a side view of a cone shape formed along a length of repair pipe undergoing expansion inside a host conduit using the apparatus and method of Figure 8, including a cone shape length “I”, a diameter “d” of repair pipe in the area in which wire is yet to be removed, a diameter “D” of the host conduit, strip material feed in velocity “v1”, and wire removal velocity “v2”.DETAILED DESCRIPTION OF EMBODIMENT(S) OF THE INVENTION

[0055] For simplicity and illustrative purposes, the present disclosure is described by reference to embodiments thereof. In the following description, numerous details are set forth in order to provide a thorough understanding of the present disclosure. It will be readily apparent however, that the present disclosure may be practiced without limitation to the specific details of the one or more embodiments. In other instances, some features have not been described in detail to avoid unnecessarily obscuring the present disclosure.

[0056] In the interest of brevity, the same reference numerals that are used to reference some features in the prior art apparatus illustrated in Figures 1 to 6, including for example host pipe (10), repair pipe (12), strip material (16), male locking edge (18), female locking edge (20), pressing force (22), male locks (24), female locks (26), wire (30), base (36), upstanding tees (38), tee stems (39), tee heads (40) and cone (42), are also used in the description and drawings to reference equivalent or similar features that exist in embodiment(s) of the present disclosure.

[0057] The present invention relates to an apparatus and method for the controlled internal lining of conduits (10) using strip material (16) having a cross section illustrated according to an embodiment in Figure 7. It is to be understood that the shape, configuration and dimensions of the profile (16) illustrated in Figure 7 are exemplary only and the present invention is not limited to same. The apparatus (100) for controlling the internal lining of conduit (10) is shown in Figure 8 as incorporating a number of components according to an embodiment, the components including a vehicle (102) parked at street level (104) and a pipe liner winding machine (106) positioned down a first man hole (108). However, again it will be appreciated that other variations are possible.

[0058] The vehicle (102) includes a wire feed-in drum (110) and an associated encoder (112) through which wire from the feed-in drum (110) moves before entering a drive tray (114) associated with the winding machine (106). The vehicle (102) further includes a wire removal drum (116) and associated encoder (118) through which wire (30) that is removed from the repair pipe (12) during the pipe expansion stage moves before being wound about the wire removal drum (116).

[0059] In addition to including a drive tray (114), the winding machine (106) further includes a winding cage (120) wherein strip material (16) that is stored on the vehicle (102) is fed to and driven by the drive tray (114) into the winding cage (120). Whilst not shown, the winding cage (120) may support a plurality of circumferentially spaced apart strip guides in the form of rollers that extend there-between and which assist with guiding and joining the strip material (16) to form the pipe (12). The internal diameter of the winding cage will equal the outer diameter of repair pipe (12) that is formed by the winding machine (106), hence it will be appreciated that different repair pipe diameters may be achieved by adjusting the internal diameter of the winding cage.

[0060] It will be further appreciated that the pipe (12) will continue to be formed until the forward moving end (122) of the pipe (12) reaches a second man hole (not shown) or similar end point, whereupon winding is stopped and the distal end of the helically wound pipe is fixed to avoid further rotation of the distal end. When winding resumes and wire (30) begins to be removed from the groove (35) starting from the fixed distal end of the pipe (12), the wire (30) starts to sever the sacrificial lock (24B, 26B) and in the section of pipe (12) from which wire (30) has been removed, the expansion torque exceeds the holding torque.

[0061] This causes the repair pipe (12) to start to expand commencing at the fixed distal end until the repair pipe reaches a final diameter (eg. when an external surface thereof abuts with the internal surface of the host conduit (10)). In other words, the path of least resistance is for the pipe (12) to start to rotationally slide at the fixed distal end, and the relative sliding between the overlapping male (18) and female (20) edges causes the diameter of the pipe (12) to progressively expand. Accordingly, expansion is achieved by first fixing and thereby stopping the turning of the entire pipe (12) at the second man hole end, and then continuing to feed strip liner (16) through the machine (106) whilst simultaneously removing wire (30).

[0062] Whilst the expansion process initiated by the winding machine (106) is not shown in Figures 7 to 9, a substantially equivalent expansion process was described earlier with reference to the prior art apparatus and method shown in Figures 3 to 6, and the reader is directed to those illustrations as well as the earlier description of this process to gainan appreciation of the configuration and movement of different components as the pipe (12) progressively expands, including the formation of a cone.

[0063] Figure 9 shows a side view of the cone shaped section (42) that is formed along the length of the pipe which progressively moves from the distal end of the pipe to the proximal end as more strip material (16) is fed in and wire (30) is simultaneously removed. The length of the cone (42) is indicated by the letter “I”, the diameter of the yet to be expanded pipe (12) is indicated by letter “d”, and the diameter of the host conduit (10) is indicated by letter “D”. The velocity of pipe liner being fed in by the winding machine (106) is indicated by “v1” whilst the velocity of wire (30) being removed from the pipe (12) during the pipe expansion process is indicated by “v2”.

[0064] The diameter D of the host conduit (10) will typically already be known by operators of the apparatus (100). If not, the diameter D can always be measured on site. This may result in the recording and input of one or more of a nominal diameter of the conduit (eg. 600mm), an actual diameter of the conduit (eg. 605mm), and / or an actual diameter of the conduit (10). The diameter D of the host pipe (10) may not necessarily be consistent along its length and there may be circumstances in which measuring the diameter profile along the length of the host conduit (10), eg. via a laser profile, may be beneficial since such inconsistencies may be taken into account when determining an appropriate speed at which to feed in liner (14) and / or remove wire (30) during the expansion process, as described in greater detail below.

[0065] The diameter d of the repair pipe (12) prior to expansion is based on the configuration of the winding machine (106) and in particular the internal diameter of the winding cage (120). In particular, the internal diameter of the winding cage (120) will be substantially equal to the outer diameter of the formed pipe (12) and will be specified by the operator(s), hence the outer diameter of the pipe (12) will also have a known value. In one example, a host conduit (10) may be 18 inches in diameter, and the cage size associated with the machine (100) for rehabilitating the pipe has a 15 inch inner diameter which results in the formation of a repair pipe having an unexpanded outer diameter of 15 inches.

[0066] Additional dimensional attributes of the repair pipe (12) that may be input by the operator, or measured and / or determined, include a width (pitch) of the strip material (16)used to form the repair pipe (12), a height of the upstanding tees (38), and a neutral axis position of the repair pipe (12) (as shown in the example cross-sectional profile of Figure 7). The pitch is a measurement of the distance between a male lock (24B) and corresponding female lock (26B). The neutral axis position of the repair pipe (12) represents a centroidal axis that extends cross-sectionally through the strip material (16) in a direction parallel to the base (36) at a location that is neither in compression nor tension during formation of the repair pipe (12).

[0067] The purpose of the encoder (112) associated with the wire feed-in drum (110) is to measure the speed at which wire (30) is being fed into the winding machine (106) during the creation of the repair pipe (12) and also during expansion. Similarly, the purpose of the second encoder (118) associated with the wire removal drum (116) is to measure the speed v2 at which wire (30) is removed from inside the pipe (12) to cause progressive pipe expansion. By using the encoder (112) to very accurately measure the speed of wire (30) being fed in, it will be appreciated that the speed v1 of strip material (16) being fed in can also be determined since both the strip material (16) and wire (30) are fed in simultaneously and at the same rate.

[0068] Every time a rotary encoder (112, 118) rotates, signals (eg pulses) are sent to a control means associated with the apparatus (100) which may include a Programmable Logic Controller (PLC) (not shown). In one example, there might be 100 pulses per revolution recorded. Using the time clock inside the PLC, the number of pulses in each 5-10 millisecond interval can be counted and on that basis the instantaneous speed of rotation (and hence speed at which wire (30) is being fed in and removed) may be calculated. The skilled addressee will appreciate that once the speed of wire feed in and removal is known, the amount (eg. length) of strip material (16) that has been fed in and the amount (eg. length) of wire (30) that has been removed can also be determined.

[0069] The ideal (set point) cone length can be automatically determined based on the final diameter to which the repair pipe (12) is to expand, whether that be up to the internal surface of the conduit (10) or some other final diameter. In other words, once it is known to what extent the repair pipe (12) needs to be expanded, the upper and lower cone length limits required to be maintained during the expansion process can be determined. In an example, a host conduit (10) has a pipe diameter of 600mm and the repair pipe externaldiameter is 550mm which is to be expanded by 50mm to cause the repair pipe external surface to abut with the internal surface of the conduit (10). The maximum profile diameter change per convolution is 5mm, therefore the minimum cone length would be 10 wraps. Since the minimum profile diameter change per convolution to allow expansion to continue is 1 mm, the maximum cone length would be 50 wraps.

[0070] In another embodiment, the ideal (set point) cone length can also be input into the controller by an operator (not shown) who may be prompted to enter an upper and lower limit (eg. upper limit of 25 wraps, and lower limit of 5 wraps) in which case the set point may be calculated as being halfway between the limits (eg. 15 wraps). Setting the cone length set point and upper / lower limits in this manner is largely achieved by experience and / or experimentation.

[0071] Accordingly, at any one point in time during the expansion process, the following values will be known based on such values being entered by an operator, such values being measured, or according to a determination (calculation) of the values:• strip material profile properties including width (pitch), tee height and neutral axis position,• host conduit diameter D,• repair pipe diameter d prior to expansion (determined by the winding cage diameter),• cone length set point including upper and lower limits, and• the speed v1 and total amount of strip (16) added.

[0072] Based on the above-listed values being known, the necessary (ie. most appropriate) speed v2 at which wire (30) is to be removed in order to maintain the desired cone length I can be determined and also maintained. In other words, one or more outputs may be generated in substantially real-time reflecting the speed v2 at which the wire (30) should be removed to maintain a desired cone length I based on the values listed above being known (ie. previously entered, measured and / or determined).

[0073] The abovementioned output may be provided in a number of different formats depending on the particular application and / or user preference, including but not limited to:• an instruction or recommendation transmitted to a device (128) of an operator to enable the operator to operate the winding machine (106) in a manner that causes removal of the wire (30) at the necessary speed v2 to maintain the desired cone length I; or• an automatic instruction to a controller associated with the apparatus (100) with to the winding machine (106) in particular to cause the winding machine (106) to operate in a manner that causes removal of the wire (30) at the necessary speed v2 to maintain the desired cone length I (ie. without the requirement for operator instructions).

[0074] The present invention is not limited to any particular type, location or number of “controllers” or “control means” which are described herein as being used to receive and / or transmit instructions and to control operations such as the feed in of strip material, the feed in of wire, the removal of wire, etc. The skilled addressee would understand that there are several controller options available in this regard, including remotely located control means, and these are all considered to be within the scope of the present invention.

[0075] The person skilled in the art would also appreciate that there may be circumstances in which one or more of the above-listed values (and hence the speed v2 at which wire (30) should be removed to maintain a desired cone length I) may change during an expansion process. In one example, the internal diameter D along the host conduit (10) may not be consistent along its length and this may be known due to a previous internal scan of the host conduit (10). In other words, there may be fluctuations in the measured internal diameter D of the host conduit (10), and in these circumstances, the apparatus (100) may automatically account for such fluctuations and alter the output accordingly (eg. synchronize the wire removal speed v2 at the appropriate times during the progressive expansion of pipe (12) to ensure that the desired cone length I is maintained throughout the expansion).

[0076] In an alternative embodiment to that described above in which the output reflects the speed v2 at which wire (30) should be removed, the speed v2 at which wire (30) is removed may be known or maintained constant during the pipe expansion. In this scenario, the output may reflect a determination of the speed v1 at which strip material (16) should be fed in during expansion (eg. an instruction to automatically synchronize the speed v1 in order to maintain a desired cone length I).

[0077] In this regard, the skilled addressee will appreciate that the cone length I can be altered during expansion by either removing wire (30) at a different speed v2 or by feeding strip material (16) in at a different speed v1. Accordingly, the present invention is not limited to generating outputs reflecting solely a determination of speed v2 at which wire (30) should be removed. The output may instead reflect a determination of speed v1 at which strip material (16) is to be fed in, or potentially a combination of both v1 and v2. In other words, according to an embodiment, either or both of the speeds v1 and v2 could be automatically synchronized to maintain a consistent desired cone length I. In this embodiment, the control means may be used to calculate the speed v2 that wire should be removed and / or the speed v1 that profile should be added, to ensure the length of the cone shape is maintained substantially at or within a predetermined cone length, according to the following general relationship:Wire Speed v2 Host Pipe DiameterProfile Speed vl Host Pipe Diameter — Cage Diameter

[0078] Accordingly, in the earlier described example in which a host conduit (10) has a diameter of 18 inches and the repair pipe outer diameter is 15 inches, maintaining an appropriate cone length I may require a profile feed to occur at ~ 6.5 metres per minute whilst wire (30) is pulled out at a rate of ~ 40 metres per minute.

[0079] Circumstances may arise in which the amount of wire (30) that is removed may be recorded as slightly more than the amount of wire (30) that was originally added, eg. due to stretching of the wire (30) during removal as the wire severs the sacrificial lock. The stretch on the wires may be determined empirically by experimentation (eg. by knowing the actual length of profile that is used for a particular run, one may compare this to the amount calculated by use of the encoders (112, 118). A correction factor may also be used to equate the two. Furthermore, the amount of wire (30) added may not beprecisely the same as the amount of strip material (16) added since the profile may stretch when formed into a pipe (12). Again, a correction factor may be applied. In each instance the correction factor may be in the order of 0 to 1 %. Once the correction factors are known, they may remain constant for all subsequent runs.

[0080] One or more control means may be operable to generate one or more additional outputs, including but not limited to, the actual cone length I during the repair pipe expansion process, the location of the wire representing the point along the repair pipe (12) at which the wire (30) is cutting the sacrificial lock (eg. the wire is at 53m along the pipe), the location at which the repair pipe (12) has fully expanded (eg. 51 metres of pipe has fully expanded), and the length of the repair pipe (12) which has been formed at any one point in time during the pipe formation process. In this regard, it can be beneficial to know where the process is up to during pipe formation and expansion. For example, if the pipe (12) was 100m long and it was known that there was a “tight spot” at the 60m mark, the apparatus (100) and / or operator will be able to identify when the tight spot is about to be encountered and make adjustments to the operation of the apparatus (100) accordingly. In another example, knowing the position of the wire (30) which is cutting the sacrificial lock assists the apparatus (100) and / or operator to know when to commence the ’’finishing procedure” which involves matching the wire removal speed to the profile feed in speed in order to cause the cone length I to reduce until it fully expands the last part of the pipe (12).

[0081] An additional output that may be determined is the cumulative cone length which may differ from the cone length set point. The cumulative cone length may be determined according to a measurement of the actual cone length during the repair pipe expansion process. When the cumulative cone length is determined during the pipe expansion process as being different to the cone length set point, the control means may be operable to generate an output to alter the speed at which wire (30) is being removed and / or strip material (16) is being fed in to cause the actual cone length to align with the cone length set point. In one example, an operator may initially receive an instruction to cause wire removal to occur at a speed of 50m / min to maintain a constant cone length of 15 wraps. If the actual speed was set at say 49 m / min, the cone length would reduce. Therefore, after 1 minute the actual cone length may reduce from 15 to 14 wraps, after 2 minutes to 13 wraps, after 3 mins to 12 wraps, etc, and this is likely to require correction.

[0082] If after 3 minutes the cone length comprises 12 wraps and the operator adjusts the actual wire speed back to 50 m / min, the cone length would remain at 12 wraps. However, since the cone length set point is 15 wraps, the operator is required to adjust the wire speed to compensate, which can be achieved in a number of ways. For example, the operator may be directed to adjust the wire removal speed to say 51 m / min for 3 mins to get back to a cone length of 15 wraps. Alternatively, the operator could be directed to adjust the wire removal speed to 53m / min for 1 min, or 100m / min for a few seconds. It will be understood that any reference to “operator” in this and the preceding paragraph relating to cone length compensation could equally be replaced with “controller” in a scenario where instructions are being provided to a machine rather than an operator.

[0083] Determining the extent to which the actual cone length has increased or decreased will correspond with the amount of profile that has had wire removed, which the skilled person will appreciate is the same as knowing the speed of wire removal and the time it has been removed for. Accordingly, the amount of profile that has had wire removed may be determined by measuring the total distance that each of the front and rear points of the cone have travelled and subtracting them (the front point being where the repair pipe starts to make contact with the host conduit (10) and the rear point being where the wire (30) is yet to be removed). If this is measured continuously, a distance difference (or cumulative distance difference) can be calculated. The skilled addressee will appreciate that a similar calculation may be made based on measuring the actual speeds at the same two points, which is effectively the same calculation since the same measurements (ie. speed and time) are used.

[0084] Another reason for specifically measuring the total distance travelled by each of these two points is to be able to display to an operator where in the host conduit (10) the expanded repair pipe (12) actually is, and thereby how far to go until the destination is reached.

[0085] It is to be further understood that the present invention is not limited to any one configuration of winding machine (106). The winding machine should be capable of operating inside a man-hole (108) as shown in Figure 8 to receive strip material (16) from street level (104) to form (ie. wind) a helically wound pipe (12) into the host conduit (10) whilst simultaneously feeding in wire (30) and any required lubricants and adhesives. Themachine (106) should also be capable of causing the subsequent expansion of pipe (12) by progressively removing wire (30) to sever the sacrificial lock which is helically formed inside the pipe (12) thereby causing the pipe diameter d to progressively expand. In the interest of brevity, since the components and functionality of such winding machines (106) including the operation of the drive tray (114) and winding cage (120) are generally known in the art, they are not described in detail herein.

[0086] It will be appreciated that by implementing the present invention according to the above-described embodiment(s), a camera operating inside the pipe (12) is no longer required. Further, an operator (not shown) no longer needs to monitor a camera display and thereby manually alter feed speeds to ensure that an appropriate cone length I is maintained, ie. to ensure that the cone length does not reduce to a point to cause the pipe (12) to not become fully expanded, or does not increase to a point to cause pipe failure. An operator can still manually alter feed speeds if preferred (this can be accommodated by providing relevant outputs for display to the operator rather than providing instructions directly to the machine(s)), but this can now be achieved without the use of a camera.

[0087] In a particular example, an operator may be located on street level (104) and may access a control system, which may be in the form of a portable device or a device installed in the vehicle (102) or some other device, which allows the operator to view generated outputs and, if necessary (ie. where the output is in the form of an instruction or recommendation to the operator), enter relevant requests to cause the pipe to be formed inside the host conduit (10) and subsequently expanded accordingly.

[0088] Such requests may include but are not limited to a speed v1 at which to feed in strip (16) according to an instruction provided to the operator, and / or a speed v2 at which to remove wire (30) during expansion according to an instruction provided to the operator. Accordingly, it will be appreciated that in accordance with the generated output, the control system may either automatically cause speed v1 and / or v2 to be synchronized to ensure a desired cone length I is maintained, or provide instructions and / or recommendations to the operator to achieve same by submitting requests via the control system. As a result of receiving such request(s), the control system is configured to operate the one or more controllers associated with the apparatus (100) accordingly. Inthis way, a pipe (12) will be formed and expanded inside the host conduit (10) in a controlled manner with minimal prospects of error.

[0089] In another example, the operator may prefer that the speed v2 at which wire (30) is removed during expansion of pipe (12) is automatically synchronized in order to maintain a consistent cone length I without requiring the operator to manually control same. In this example, the operator may enter a desired cone length I to be maintained during expansion of pipe (12), or alternatively, a desired cone length I can be automatically determined based on additional information which is either predetermined or entered by the operator. Such additional information may include the previously described inputs including the diameter d of the pipe (12) prior to expansion, and the diameter D of the host conduit (10), etc.

[0090] The control system may be operably connected to each of the winding machine (106), which controls the speed at which strip material (16) is fed into the host conduit (10), as well as each of the encoders (112) and (118) which respectively measure the speed at which wire (30) is fed in and subsequently removed from the pipe (12). It is well understood that an encoder is an electromechanical device that reads the position of a rotating component, such as a motor shaft, and generates an electrical output signal related to that position as described earlier herein. Such encoders thereby enable a very accurate measurement of speed and amount of wire (30) that is fed in and removed, which is necessary to enable the determinations and outputs described herein. In this way, the control means may be utilized to ensure the controlled internal lining of the host conduit (10) according to the operator’s preference(s).

[0091] It will also be appreciated that the operator need not necessarily be located at street level (104) and could operate the control system (including to enter any necessary requests to form a pipe (12) inside the host conduit (10)) from a remote location. In this regard, and as shown in the embodiment of Figure 8, the apparatus (10) may include a device (124) that enables transmission and receipt of wireless communications via an appropriate network (126) with one or more operator devices (128) located a distance away from the site.

[0092] Whilst a camera installed inside the pipe (12) is not necessary, it will be appreciated that installing a camera (not shown) and causing a real-time display to beprovided to a remote operator may be preferred since it will assist a remote operator with respect to ensuring that the formation and expansion of pipe (12) is progressing in the manner intended. Indeed, the remote person need not necessarily be an operator and may instead be an individual assigned to oversee the pipe formation / expansion process, to assess the performance of an operator who is based on-site, and / or provide feedback and guidance as required.

[0093] Irrespective of whether an operator or other user is located down the manhole (108), at street level (104), or remotely, they may be provided with access (eg via device (128)) to a user interface display (not shown) which enables the user to view all relevant data and feedback pertaining to the pipe formation and expansion. Such an interface may include all relevant, inputs, measurements and outputs that have been described herein, including the speed and amounts of strip material (16) and wire (30) being fed in during pipe formation, and the speed and amount of additional strip material (16) being fed in (and wire (30) removed) during pipe expansion. In addition, such an interface could provide access to the above-described camera display (if applicable), as well as other cumulative information including the length of the cone, etc.

[0094] Data and information received or determined by the one or more control means described herein may also be stored. Indeed, significant amounts of data may be stored relating to different installations, all of which may be accessed remotely in real-time or after the event. For example, an administrator may be provided with the ability to view particular details relating to pipe installations undertaken on particular dates according to a data log that is captured and that is remotely accessible. Such data logs may also include videos captured by any camera used during the particular installation, and may facilitate the creation of reports including graphs and the provision of insight into the way in which customers are operating the equipment with the ability to provide valuable feedback or even on-the-job training.

[0095] It will also be appreciated that one or more Artificial Intelligence (Al) techniques could be used by the one or more control means to learn from the significant amounts of data captured. The identification of specific problems that are encountered during pipe installation, and remedies which have been used to successfully overcome same, and certain remedies which have also been logged as being unsuccessful, represent usefuldata which a machine learning or similar algorithm may utilize to improve subsequent outputs including instructions and recommendations to be provided to the apparatus (100) and / or an operator with increased prospects of preventing or minimizing similar issues.

[0096] Whilst the speed at which strip (16) is being fed in and wire (30) is being removed may be automatically controlled, some operators or some particular applications may require the operator to be able to manually override certain automatic synchronisations during pipe formation and expansion. In this regard, the user interface may also provide operation recommendations (eg. real time instructions). As previously described, such recommendations may be based on the determination of a speed at which additional strip material (16) should be fed in and / or wire (30) removed during a pipe expansion process in order to maintain a particular cone length.

[0097] However, in an alert scenario, the recommendation may be generated in view of an unexpected event which has been identified. For example, the unexpected event may be a fluctuation in cone distance determined during pipe expansion. In this example, the recommendation may include guidance sufficient to enable the operator to manually alter speeds v1 and / or v2 to ensure the cone length returns back into a target zone and is maintained at a desired length.

[0098] One way in which the speed v1 at which strip material (16) is fed into the host conduit (10) may be measured is based on the amount of power being used to turn a motor associated with the drive tray (114) of the winding machine (106). In this regard, the power may be measured by the hydraulic pressure required to turn the motor.

[0099] There is a non-linear relationship between the length of the cone I during expansion of pipe (12) and the power required to add more profile (16) during expansion. Accordingly, it will be appreciated that the cone length I may also be prevented from becoming too short by incorporating a fail safe (eg. an alarm) that is triggered based on the hydraulic pressure rising too steeply. For example, if a desired cone length (cone length set point) has been determined or specified by an operator (eg. a cone length that corresponds with 15 convolutions (wraps) of strip material (16)), then the fail safe may operate such that when the hydraulic pressure rises according to a predetermined threshold rate, the control means recognises that it is likely the cone length I has reducedbelow a lower cone length limit (eg. 5 wraps), and an alert may be triggered. This requires that the hydraulic pressure be measured very accurately and at very frequent intervals (eg. approximately 20 hertz).

[0100] The raw pressure signals may also need to be filtered and smoothed such that a pressure signal is accurate to approximately + / -1 Opsi (in 1200psi), ie + / - 1 %. With a signal of this accuracy the rate of change of the pressure can be correlated to the cone length I, and with this correlation the control means can over-ride the wire speed setting and cause an action to occur to remedy the issue, eg. rapidly pull wire (30) to avoid a cone shortening event.

[0101] It is to be understood that other automatic override options may be possible based on monitoring other parameters, including but not limited to, maintaining regular measurements in relation to the speed v2 at which wire (30) is removed, and the speed v1 at which additional strip material (16) is being fed during expansion. In this regard, the remedial action may involve automatically altering either or both speeds, the direction of feed of strip material (16), etc.

[0102] As previously mentioned, different forms of strip material (16) may be used as compared with that which has been illustrated and described herein. For example, the male longitudinal edge associated with a strip (16) may include a different configuration of male lock, and likewise, the female longitudinal edge may include a different configuration of female lock for receiving same.

[0103] It will be appreciated by persons skilled in the relevant field of technology that numerous variations and / or modifications may be made to the invention as detailed in the embodiments without departing from the spirit or scope of the invention as broadly described. The present embodiments are, therefore, to be considered in all aspects as illustrative and not restrictive.

[0104] Throughout this specification and claims which follow, unless the context requires otherwise, the word “comprise”, and variations such as “comprises” and “comprising”, will be understood to imply the inclusion of a stated feature or step, or group of features or steps, but not the exclusion of any other feature or step or group of features or steps.

Claims

The claims defining the invention are as follows:1 . An apparatus for controlling the internal lining of a conduit requiring rehabilitation, the apparatus including: a means of causing, during a repair pipe formation process, strip material having a male and female locking edge to be helically wound such that male and female locking edges interlock to form a repair pipe that is fed into the conduit requiring rehabilitation, the interlocking male and female edges including a sacrificial lock; a means of simultaneously feeding an amount of wire that substantially corresponds with the amount of strip material being fed in to form the repair pipe such that the resultant repair pipe includes a strip of helically wound wire along its length that is removable from the inside of the repair pipe; a means of progressively removing, during a subsequent repair pipe expansion process which seeks to increase the diameter of the repair pipe to a final diameter inside the conduit, the wire from inside of the repair pipe from a distal to a proximal end thereof at the same time as additional strip material is being fed in to thereby cause the wire to progressively sever the sacrificial lock which causes progressive expansion of the repair pipe from the distal to the proximal end, wherein during the expansion process a cone shape is formed in the repair pipe between the section of pipe from which wire is yet to be removed and the section of pipe that has expanded inside the conduit; and a control means operable to ensure that the length of the cone shape is maintained substantially between an upper and lower cone length limit that enables expansion of the repair pipe up to the final diameter, including by generating an output according to one or more dimensional attributes of the repair pipe prior to expansion, the diameter of the conduit, and the upper and lower cone length limits, the output reflecting one or more of: a speed at which the strip material should be fed in during the repair pipe expansion process to ensure that the length of the cone shape is maintained substantially within the upper and lower cone length limits, and a speed at which the wire should be removed during the repair pipe expansion process to ensure that the length of the cone shape is maintained substantially within the upper and lower cone length limits.

2. An apparatus according to claim 1 , wherein a cone length set point representing a cone length value between the upper and lower cone length limits is used by the control means to generate said output.

3. An apparatus according to either claim 1 or claim 2, wherein the diameter of the conduit used by the control means to generate said output includes one or more of: a nominal diameter of the conduit requiring rehabilitation, an actual diameter of the conduit requiring rehabilitation, and an actual diameter of the conduit taking into account diameter changes along the length of the conduit requiring rehabilitation.

4. An apparatus according to any one of the preceding claims, wherein the one or more dimensional attributes of the repair pipe prior to expansion, used by the control means to generate said output, includes at least the outer diameter of the repair pipe prior to expansion.

5. An apparatus according to claim 4, wherein the means of causing strip material to be helically wound to form the repair pipe is a winding machine that includes a winding cage that causes the strip material to be helically wound and for the male and female locking edges to interlock, wherein the outer diameter of the formed repair pipe prior to expansion is substantially equal to the internal diameter of the winding cage.

6. An apparatus according to either claim 4 or claim 5, wherein the strip material includes a base which forms the internal surface of the formed repair pipe, and a series of upstanding structural tees each comprising a stem and head for providing rigidity to the pipe.

7. An apparatus according to claim 6, wherein the one or more dimensional attributes of the repair pipe used by the control means to generate the output further includes one or more of: a width of the strip material used to form the repair pipe, a height of the upstanding tees, anda neutral axis position of the repair pipe which represents an axis that extends cross-sectionally through the strip material in a direction parallel to the base thereof, at a location that is neither in compression nor tension during formation of the repair pipe.

8. An apparatus according to claim 7, wherein the width is a measurement of the distance between a male lock associated with the male locking edge of the strip material and a corresponding female lock associated with the female locking edge of the strip material.

9. An apparatus according to any one of the preceding claims, wherein an actual amount of strip material added and the speed at which strip material is added is determined based on measuring the speed at which wire is being fed in which substantially corresponds with the speed at which strip material is being fed in.

10. An apparatus according to claim 9, wherein the speed of wire being fed in is measured using a rotary wire encoder.

11. An apparatus according to either claim 9 or claim 10, wherein the control means is configured to: detect when the determined actual amount of strip material being added and the speed at which strip material is being fed in corresponds with the previously determined speed at which the strip material should be fed in during the repair pipe expansion process to ensure that the length of the cone shape is maintained substantially between the upper and lower cone length limits, and in the event that there is a discrepancy, generating an output reflecting the extent to which to adjust the speed at which strip material is being fed in to address the discrepancy.

12. An apparatus according to any one of claims 1 to 8, wherein an actual amount and speed at which wire is being removed during the pipe expansion process is determined based on measuring the speed at which wire is being removed.

13. An apparatus according to claim 12, wherein the speed of wire removal is measured using a rotary wire encoder.

14. An apparatus according to either claim 12 or claim 13, wherein the control means is configured to: detect that the determined actual amount and speed of wire removal corresponds with the previously determined speed at which the wire should be removed during the repair pipe expansion process to ensure that the length of the cone shape is maintained substantially between the upper sand lower cone length limits; and in the event that there is a discrepancy, generating an output reflecting the extent to which to adjust the speed at which wire is being removed to address the discrepancy.

15. An apparatus according to any one of claims 9 to 14, wherein the control means calculates the speed that wire should be removed and / or the speed that profile should be added, to ensure the length of the cone shape is maintained substantially between the upper and lower cone length limits, according to the following relationship:Wire Speed Host Pipe DiameterProfile Speed Host Pipe Diameter — Cage Diameter16. An apparatus according to claim 15, wherein when the amount of wire that is removed is more than the amount of wire that was originally added, or the amount of wire added is not the same as the amount of strip material added, a correction factor is automatically applied.

17. An apparatus according to any one of the preceding claims, wherein the strip material includes two sets of male and female locks, wherein one set represents the sacrificial lock.

18. An apparatus according to any one of the preceding claims, wherein the control means is operable to generate additional output(s) including one or more of: the actual cone length during the repair pipe expansion process, the location of the wire representing the point along the repair pipe at which the wire is cutting the sacrificial lock, the location at which the repair pipe has fully expanded, andthe length of the repair pipe which has been formed during the pipe formation process.

19. An apparatus according to any one of claims 2 to 18, wherein a cumulative cone length is determined according to a measurement of the actual cone length during the repair pipe expansion process, and when the cumulative cone length is determined as being different to the cone length set point, the control means is operable to generate an output to alter the speed at which wire is being removed and / or strip material is being fed in during the pipe expansion process to cause the actual cone length to correspond with the cone length set point.

20. A method for controlling the internal lining of a conduit requiring rehabilitation, the method including: causing, during a repair pipe formation process, strip material having a male and female locking edge to be helically wound such that male and female locking edges interlock to form a repair pipe that is fed into the conduit requiring rehabilitation, the interlocking male and female edges including a sacrificial lock; simultaneously feeding an amount of wire that substantially corresponds with the amount of strip material being fed in to form the repair pipe such that the resultant repair pipe includes a strip of helically wound wire along its length that is removable from the inside of the repair pipe; progressively removing, during a subsequent repair pipe expansion process which seeks to increase the diameter of the repair pipe to a final diameter inside the conduit, the wire from inside of the repair pipe from a distal to a proximal end thereof at the same time as additional strip material is being fed in to thereby cause the wire to progressively sever the sacrificial lock which causes progressive expansion of the repair pipe from the distal to the proximal end, wherein during the expansion process a cone shape is formed in the repair pipe between the section of pipe from which wire is yet to be removed and the section of pipe that has expanded inside the conduit; and generating, according to one or more dimensional attributes of the repair pipe prior to expansion, the diameter of the conduit, and upper and lower cone length limits that enable expansion of the repair pipe up to the final diameter, an output that ensuresthat the length of the cone shape is maintained substantially within the upper and lower cone length limits, the output reflecting one or more of: a speed at which the strip material should be fed in during the repair pipe expansion process to ensure that the length of the cone shape is maintained substantially within the upper and lower cone length limits, and a speed at which the wire should be removed during the repair pipe expansion process to ensure that the length of the cone shape is maintained substantially within the upper and lower cone length limits.21 . An apparatus or method according to any one of the preceding claims, wherein: the output(s) include one or more automatic instructions transmitted to the apparatus to cause the apparatus to operate in accordance with the one or more automatic instructions, or the output(s) include one or more instructions transmitted to a device associated with a human operator to enable the operator to view the one or more instructions and cause the apparatus to operate in accordance with the one or more instructions.

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