METHOD

TECHNICAL FIELD The present invention relates to pipelines, especiaiiy but not exclusively to apparatus for use in the maintenance or installation of pipelines. More particularly, though not exclusively, the invention relates to pressurised fluid systems and components thereof for use or when used in such apparatuses. BACKGROUND

Maintenance, upgrading and replacement of ageing utilities pipeline infrastructures are major issues facing utilities companies such as water and gas utilities companies. Pipeline networks typically include main supply pipelines (also referred to as the '"mains" supply) and consumer service connection pipelines. The consumer service connection pipelines are connected to the main supply pipelines typically by means of a T- connection, to deliver a supply of fluid such as water or gas to a consumer's premises from the main supply pipeline. Utilities supply pipelines are typically located underground, presenting substantial access issues when maintenance, upgrading or replacement is required.

Ageing pipelines are vulnerable to failure and leakage of fluid from pipelines is a known hazard particularly in the case of gas leakage.

One solution to reducing the cost of replacement of pipelines is to install replacement pipeline within pre-existing pipeline, including the main pipeline and consumer service connection pipeline, leaving the pre-existing main pipeline and pre-existing consumer service connection pipeline in place. The replacement main pipeline has an external diameter that is smaller than the internal diameter of the pre-existing main pipeline, allowing it to fit within the pre-existing main pipeline infrastructure. Similarly, the replacement consumer service connection pipeline has a diameter that is smaller than the pre-existing consumer service connection pipeline. The replacement main pipeline may be referred to as a "main pipeline liner" or "mains liner" because it effectively lines the pre-existing main pipeline. Similarly the replacement consumer service connection pipeline may be referred to as a "service connection liner" since it effectively lines the pre- existing consumer service connection pipeline. The consumer service connection pipeline may be of the Serviflex (RTM) type, being a twin wall corrugated flexible polyethylene liner pipe supplied by Radius Systems Ltd, South Normanton, Alfreton, Derbyshire, UK.

In known methods of replacement pipeline installation, the replacement pipeline is installed within the pre-existing pipeline by pulling the replacement pipeline through the pre-existing pipeline. Connection of the replacement consumer service connection pipeline to the replacement main pipeline is made by excavating ground above the location at which the pre-existing service connection pipeline connects to the pre-existing main pipeline. Installer personnel may then remove a portion of the pre-existing main pipeline and pre-existing service connection pipeline in order to expose the replacement pipelines that have been installed therein. A T-connector is then installed on the replacement main pipeline and the replacement service connection pipeline coupled to the replacement main pipeline via the T-connector. The T-connector is typically attached to the main pipeline by forming an electrofusion bond between the T-connector and the main pipeline in a known manner.

In methods of installing a replacement pipeline within a pre-existing pipeline, or even in other processes of repairing or maintaining existing pipelines, it is frequently necessary to utilise an apparatus, often a remote-controlled apparatus, that is insertab!e into and propellable along the pipeline in order to carry out one or more surveying, operational, testing, maintenance or repair procedures from within the pipeline. Such "pigs" or "robots" are often designed to be as small and lightweight as possible, and to that end it is common practice to provide such apparatuses with a multi-strand or multi-tube tether or umbilical cable via which it is linked to an above-ground control station and sources of electrical power, operational control signals, supplies of pressurised fluid to onboard pneumatic and/or hydraulic systems, and suchlike. However, such known techniques for supplying such services especially supplies of pressurised fluid to onboard pneumatic and/or hydraulic systems, have several practical shortcomings. These include the necessity for bulky and complex tethering/umbilical cabling, which adds to the size and weight of material that the robot has to be able to pull, in addition to itself, as it travels along the pipeline, and also resulting in slow response times. These problems can become more pronounced especially as distances from the ground-based control station to the robot become large and/or when a particularly high level of responsiveness or control precision is demanded of a particular onboard operational system.

It is an aim of the present invention to address disadvantages associated with the prior art such as those discussed above.

SUMMARY OF THE INVENTION

Embodiments of the invention may be understood with reference to the appended claims.

Aspects of the present invention provide an apparatus or robot, a system and a method.

In one aspect of the invention for which protection is sought there is provided apparatus for performing at least one operation on a pipeline from within the pipeline, the apparatus being propellable along and within the pipeline, wherein the apparatus comprises:

at least one operational means for performing the at least one operation on the pipeline from therewithin, and

actuation means for actuating operation of the at least one operational means, the actuation means comprising a pressurised fluid,

wherein a supply of said pressurised fluid is provided in or on the apparatus.

Some embodiments of the invention may be configured for operation in pipelines having a diameter of 1 m or less, optionally in the range from 10mm to 1m. Some embodiments may be configured for operation in pipelines having a diameter in the range from 50mm to 200mm, optionally from 50mm to 100mm, optionally in the range from 75mm to 90 mm.

Alternatively the supply of the said pressurised fluid may be defined as being carried with, or on, or in, the apparatus, especially as it moves longitudinally along the pipeline. In some embodiments of the invention the apparatus may be constituted by a robot which forms part of an overall system, including control means for controlling operation of the at least one operational means, for performing the at least one operation on the pipeline from therewithin. Accordingly, in another aspect of the invention for which protection is sought there is provided a system for performing at least one operation on a pipeline from within the pipeline, wherein the system comprises:

a robot comprising at least one operational means for performing the at least one operation on the pipeline from therewithin,

actuation means for actuating operation of the at least one operational means, the actuation means comprising a pressurised fiuid, and

control means for controlling actuation of the actuation means;

wherein a supply of said pressurised fluid is provided in or on the apparatus.

In another aspect of the invention for which protection is sought there is provided a method of performing at least one operation on a pipeline from within the pipeline, the method comprising :

providing an apparatus or robot according to the first aspect of the invention or any embodiment thereof;

inserting the apparatus or robot into the pipeline and propelling it therealong to a desired site of operation; and

actuating the actuation means so as to actuate operation of the at least one operational means of the apparatus or robot;

wherein the actuation of the actuation means is effected by pressurised fluid from the supply thereof provided in or on, preferably onboard, the apparatus or robot.

In embodiments of the invention the pipeline may be an existing pipeline or it may be a replacement pipeline to be inserted within a pre-existing pipeline.

In embodiments of the invention the at least one operation on the pipeline which is to be performed by the apparatus may be selected from any operation which employs a source of pressurised fluid, e.g. a gas or a liquid, to actuate or control same. Thus the operation may be any operation which uses a pneumatic or hydraulic actuation means to effect its operation. Examples of such operations may include any one or more of the following (which list is to be considered as non-exhaustive):

- a traction or drive operation, e.g. for moving the apparatus with respect to one or more walls of the pipeline, e.g. for propelling the apparatus along the pipeline or manoeuvring or aligning it (e.g. rotating it about the longitudinal axis of the pipeline and/or moving it longitudinally) therewithin into a desired positon for performing one or more other operations;

- a surveying operation, e.g. for observing or detecting a particular condition of or location in the pipeline in order to diagnose or prepare for one or more other operations; - a drilling operation, e.g. for drilling an aperture in a wall of the pipeline for the purpose of forming a service connection, such as a consumer utility service connection, thereto;

- an insertion operation, e.g. for physically inserting one or more connection or other components, e.g. a T-connector, into an aperture formed by a drilling operation;

- a welding operation, e.g. for completing an insertion operation or effecting a repair or service connection operation;

- a repair operation, e.g. for repairing a wall of the pipeline or a service connection thereto;

- a testing operation, e.g. for pressure-testing a pipeline subsequent to an insertion, welding or repair operation;

- a cleaning operation, e.g. for cleaning an internal wall or surface of the pipeline or clearing debris or waste material from within the pipeline. The apparatus may be constructed and configured for performing any one or more of the above operations by virtue of its comprising respective operational devices housed within or provided by one or more respective operational modules, e.g. one or more modules arranged longitudinally or sequentially in the apparatus, each constructed and configured for performing a respective such operation or task.

Actuation of the one or more operational devices may be effected by the actuation means, preferably under control of control means, for example part of an overall control system of the apparatus or system. Such control means may be located at least partly on or in the apparatus itself, or it may be located at least partly at ground level and connected to the apparatus via a tether or umbilical cable.

It is a primary feature of embodiments of the invention that at least one or more of the above operational devices or modules is/are characterised by employing an, or a respective, actuation means to effect its operation, which actuation means comprises a pressurised fluid device. Such a pressurised fluid device may be a pneumatic (i.e. gas- operated) or a hydraulic (i.e. a liquid-operated) device, which relies for its operation on a source of the relevant fluid. For example, a pneumatic device may be supplied from a source of compressed air, whilst a hydraulic device may be supplied from a source of a hydraulic fluid, e.g. an oil or aqueous liquid.

Where a plurality of operational devices or modules are provided in the apparatus, each may be independently selected from a pneumatic or a hydraulic device, so that within the scope of the invention it is possible for different devices or modules to be operated by different types of pressurised fluid device, or alternatively they may all be operated by the same type of pressurised fluid device. Each such operational device may be supplied from its own dedicated source of pressurised fluid, or alternatively two or more (or a plurality of) such operational devices may be supplied from a common pressurised fluid source.

In accordance with embodiments of the present invention a supply of the or a respective pressurised fluid is provided in or on the apparatus. In other words, the or the respective supply of the fluid is provided or located onboard the apparatus, or is carried thereby as it moves longitudinally along the pipeline. Thus, any supply of the pressurised fluid to the one or more operational devices for the purpose of actuating same is not derived directly from an external fluid supply source, e.g. via the tether or umbilical cable linking the apparatus to a ground-based control station. This is in contrast to prior art pigs or robots in known pipeline maintenance or repair systems, which generally rely for pneumatic or hydraulic system operation on an external supply of the relevant fluid, usually from ground level via the tether or umbilical cable used to convey power, control signals and any other relevant services to the pig or robot.

By placing the supply of the pressurised fluid onboard the apparatus in accordance with embodiments of the invention, it is possible to improve response times and/or actuation or operational speeds of the relevant one or more pneumatic- or hydraulic-actuated devices when their actuation is initiated or controlled by the relevant actuation means. Furthermore, it also enables a reduction in size, weight, and complexity of any tether or umbilical cable that is employed to provide power, control signals and/or other services to the apparatus from ground level whilst the apparatus is within the pipeline.

In some embodiments of the invention the supply of the pressurised fluid may be constituted by an onboard reservoir containing an amount of the pressurised fluid. Such a reservoir is preferably mounted on or in the apparatus, e.g. at an appropriate or convenient location thereon or therein dependent on the arrangement of other components or of the operational modules thereof. The reservoir is preferably connected to its respective one or more operation devices by any suitable arrangement of one or more conduits, pipes, tubes or other fluid-communication means, in accordance with well- known techniques in the art of pneumatics or hydraulics. Where a plurality of sources of pressurised fluid are required for one or more respective operational devices, a plurality of such reservoirs of pressurised fluid may be provided. In embodiments of practical systems of the present invention there are preferably provided charging means, or filling or replenishing or loading means, for charging the one or more respective reservoirs with a supply of the pressurised fluid, preferably from a general source thereof outside the apparatus, especially from ground level, e.g. whilst the apparatus is present within the pipeline.

In one example arrangement such charging means may be substantially permanently linked to the apparatus, e.g. via an element of the tether or umbilical cable, so as to enable the one or more reservoirs to be charged as or when required whilst the apparatus remains within the pipeline. In that case the link to the apparatus may preferably be via a valve arrangement selectively operable to permit pressurised fluid to enter a or a respective reservoir only as or when required.

In another example arrangement, which may generally be more preferred, such charging means may alternatively not be permanently linked to the apparatus, so that the or the respective reservoir may be rechargeable or refillable only when removed from the pipeline, e.g. upon completion of a particular operation or series of operations, for which a single charge or fill of pressurised fluid is sufficient. This may thus avoid the need for a permanent fluid supply connection from a ground supply source to the apparatus, which can thereby circumvent typically disadvantageous consequences of poor flow characteristics associated with small diameter tubing, which typically is needed for any fluid connection embodied in a tether or umbilical cable.

In some embodiments of the invention the or the respective reservoir may contain pressurised fluid, e.g. gas (such as air) or a liquid, at a pressure that substantially equals or matches a working pressure, or an optimum working pressure, of fluid required by the one or more respective operational devices that is/are to be actuated or operated thereby. In this way no intermediate pressure regulating means between the reservoir and the respective operational device may be necessary. However in other embodiments of the invention the or the respective reservoir may contain pressurised fluid at a pressure in excess, possibly significantly in excess, of a working pressure, or an optimum working pressure, of fluid required by the or the one or more respective operational devices. In this case a suitable pressure-reduction or pressure-regulating device may be provided between the respective reservoir and the respective one or more operational devices. If desired or necessary, in embodiments where a plurality of operational devices have working pressures or optimum working pressures which are different from one another, a plurality of respective pressure- regulating devices may be provided at or in respect outlets or feed conduits leading from the or a respective reservoir. Such embodiments in which a or a respective reservoir is "overcharged" with pressurised fluid may in practice be advantageous, because this enables the reservoir to be intermittently supplied, as or when required (even during operation of a relevant operational device), with a charging amount of pressurised fluid at an elevated pressure in comparison with the working pressure(s) of the respective one or more operational devices, which can lead to reduced charging times. Thus, in some embodiments of the invention it may be desirable to maintain a pressure differential across the or the respective reservoir, that is to say, a pressure in a supply conduit at its inlet is maintained so as to be greater than a pressure in one or more feed conduits at or from its outlet(s).

In some embodiments any one or more given outlets or outlet conduits of the or the respective reservoir may be constructed and/or configured to provide a substantially fixed or constant output fluid pressure.

However, in other embodiments, which possibly may be practically more useful in certain situations, any one or more given outlets or outlet conduits of the or the respective reservoir may be constructed and/or configured to provide a variable output fluid pressure. In this case a respective valve in the or the respective outlet or outlet conduit may be connected to a, or a respective, control device, which may be located onboard the apparatus or located at or as part of the preferred ground-based control station, so that the valve receives signals therefrom to control its operation to permit a desired flow or a predetermined flow rate of fluid to flow therethrough. Such a control device may for example comprise one or more of an !/P (current/pressure) converter, an E/P (energy/pressure) converter and/or a V/P (voltage/pressure) converter, in order to control the or the respective valve to provide an appropriate output fluid pressure dependent of the current/energy/voltage of the respective control signai(s) supplied to it. Practical examples of suitable valve and converter devices are readily available in the art of pneumatic and hydraulic control systems for e.g. robotics. In practical embodiments of the invention the one or more reservoirs located onboard the apparatus may be connected to the relevant one(s) of the respective pressurised fluid- actuated operational devices by any suitable arrangement of one or more manifolds, conduits, pipes, tubes or other fluid-communication means. Preferably such fluid communication means may be provided within the body of the apparatus, especially internally thereof so as not to interfere with passage of the apparatus along the pipeline or proper operation of its respective operational device(s). If desired or necessary, in cases where the apparatus comprises plural modules, each for conducting a respective given operation or task, and pressurised fluid from a given reservoir is required by one or more operational devices in different modules, then it may be a preferred feature that such fluid communication means are provided which interconnect, in a fluid intercommunicating manner, two or more adjacent, or even non-adjacent, modules. In some practical embodiments the or each reservoir for containing an amount of the required pressurised fluid may be in the form of a tank. The tank may be of any suitable or convenient shape, e.g. cylindrical or part-cylindrical, cuboidal, box-like or other polyhedral shape. Other shapes may also be useful. In some cases an optimum shape for the tank may be to some extent be dictated by the physical space and shape available onboard the apparatus in the region in which the tank is to be accommodated.

In certain other practical embodiments the or each reservoir for containing an amount of the required pressurised fluid may be in the form of a tube or hose, which may be configured into any desired or suitable shape, e.g. a coil or other convoluted configuration. Such a tube or hose as the reservoir may for example have a diameter up to about 15mm. If necessary or desired in such embodiments, the coiled or otherwise configured tube or hose may be contained within a frame, shroud, container or like means for maintaining its stable configuration. In many practical example forms, regardless of whatever form or shape the or each reservoir has, the reservoir may preferably have an inlet for providing a means of charging or filling the reservoir and at least one outlet for providing a means of supplying fluid to the respective one or more operational devices to be actuated by the fluid. Depending on the overall arrangement of reservoir(s) and operational device(s), any one given reservoir may have either a single outlet, e.g. for supplying fluid to one or more operational devices simultaneously (such as in the case of plural devices, e.g. in a parallel, or even series, arrangement), or alternatively a plurality of outlets, e.g. for supplying a plurality of devices optionally in any desired shared or dedicated fluid supply line configuration. If desired or necessary, either or both of the inlet or outlet(s) may be provided with one or more respective valve(s) to allow passage therethrough of fluid in one direction only.

Particularly in the case where the fluid contained in the or at least one onboard reservoir in the apparatus is compressed air, this may in some embodiments be additionally useful in providing the apparatus with an overall density which renders it buoyant in water or other liquid which may be contained in the pipeline in which the apparatus is to be used. In this manner the onboard reservoir may act additionally as a buoyancy tank, thereby enabling or facilitating the passage of the apparatus through water or other liquid contained within the pipeline along which the apparatus is to travel. In an alternative aspect of the invention for which protection is sought there is provided apparatus for performing at least one operation on a pipeline from within the pipeline during a method of providing a fluid connection to the pipeline, the apparatus comprising a robot and a control line linked to a control station for controlling the robot, the robot being propellable along and within the pipeline, wherein the robot of the apparatus comprises:

at least one operational device for performing the at least one operation on the pipeline from therewithin,

actuation means for actuating operation of the at least one operational device under control from the control station, wherein the actuation means comprises a pressurised fluid,

wherein a supply of said pressurised fluid is provided onboard the robot of the apparatus.

Within the scope of this application it is envisaged that the various aspects, embodiments, examples and alternatives, and in particular the individual features thereof, set out in the preceding paragraphs, in the claims and/or in the following description and drawings, may be taken independently or in any combination. For example features described in connection with one embodiment are applicable to all embodiments, unless expressly stated otherwise or such features are incompatible.

For the avoidance of doubt, it is to be understood that features described with respect to one aspect of the invention may be included within any other aspect of the invention, alone or in appropriate combination with one or more other features.

BRIEF DESCRIPTION OF THE DRAWINGS

One or more embodiments of the invention in its various aspects will now be described, by way of example only, with reference to the accompanying drawings, in which:

FIGURE 1 is a plan view schematic illustration of a pipeline robot according to an embodiment of the present invention;

FIGURE 2 is a cross-sectional view of a typical operating environment of a pipeline robot according to an embodiment of the present invention; FIGURE 3 is a perspective view of a pneumatic supply module of the robot of FIGS. 1 & 2, which comprises an onboard reservoir of compressed air for supplying various of the operational device modules of the robot; and

FIGURE 4 is a perspective inverted view of the compressed air reservoir or tank alone of the module of FIG. 3.

DETAILED DESCRIPTION OF EMBODIMENTS

FIG. 1 is a plan view schematic illustration of a pipeline robot 100 located within a newly installed utilities main pipeline 101 . A reduced scale view of a typical operational environment of the robot 100 is shown in FIG. 2. It can be seen from FIG. 2 that, in the scenario illustrated, the robot 100 has been introduced into a newly installed main pipeline 01 via an underground inspection well 101 A. It is to be understood that the free end 10 F of the main pipeline 101 that is exposed to the well 101 A may be coupled to the free end 101 F2 of a second length of newly installed main pipeline 101 that also terminates in the well 101 A once service connection pipelines have been connected to the main pipeline 101 .

The newly installed utilities main pipeline 101 is itself located within a pre-existing main pipeline 101 E of larger diameter. By way of one working example, the robot 100 is configured to install a pipeline fitting in a newly installed main pipeline in order to allow a service connection pipeline to be connected to the main pipeline. The robot 100 achieves this by drilling an aperture in a sidewall of the pipeline and coupling the pipeline fitting to the pipeline in order to allow a fluid-tight connection to be made between the service connection pipeline and main pipeline. The robot 100 is also able to test the integrity of a joint between a service connection pipeline and the main pipeline. This allows an operator to determine whether or not a successful connection of the service connection pipeline to the main pipeline has been made.

The robot 100 has six modules coupled to one another in series. In the embodiment shown in FIG. 1 the modules are a tractor module 1 10, a pneumatic supply module 120, a drill module 130, an insertion module 140, a leak test module 150 and a trailer module 160. In some embodiments a second tractor module 110 may be coupled to the leak test module 150 instead of the trailer module 160. One or more additional modules may be included in some embodiments. In some embodiments the trailer module 160 may be eliminated. It is to be further understood that the modules may be coupled to one another in a different order in some embodiments. For example, in some embodiments the pneumatic supply module 120 may be provided adjacent the leak test module 150. In addition or instead, the pneumatic supply module 120 may be provided adjacent the insertion module 140, for example if the insertion module 140 is powered by pneumatic means such as a pneumatic piston or pneumatic motor.

Each module 1 10 - 160 has at least three support arms 11 OR, 120R, 130R, 140R, 150R, 160R that are configured to project outwardly therefrom at an acute angle with respect to a longitudinal axis of each module. The support arms 1 10R - 160R pivot about an axis at a proximal end within a body portion 110B-160B of each module 1 10-160. Each arm 11 OR - 160R is spring-loaded and carries a roller in the form of a wheel at its free end. The arms 11 OR - 160R are configured to urge the respective rollers away from the body portion 110B-160B and against an inner wall of the pipeline 101 in order to support the modules 110-160 substantially coaxially of the pipeline 101 . The spring loading of the arms 110R-160R assists the robot 100 to maintain a coaxial location whilst accommodating variations in diameter or cross-sectional shape of the pipeline 101 , for example in regions that are not circular such as elliptical or other non-circular cross- sectional shape, and to negotiate bends in the pipeline 101 . It is to be understood that maintaining a coaxial location is not necessarily critical in all applications. The tractor, pneumatic supply and trailer modules 1 10, 120, 160 each have four support arms 1 1 OR, 20R, 160R, respectively arranged in quadrature about the longitudinal axis of the modules. In the orientation shown in FIG. 1 one arm projects substantially vertically upwardly, one arm projects substantially vertically downwardly and two arms project substantially laterally in opposite directions.

The drill, insertion and leak test modules 130, 140, 150 each have three support arms 130R, 140R, 150R, one arm projecting substantially vertically downwardly and two arms projecting substantially laterally in opposite directions in the orientation depicted in FIG. 1.

In some alternative embodiments, one or more of the modules may have rollers that are attached to a body of the module rather than to spring-loaded arms. The rollers may be non-spring-loaded in some embodiments, being configured to rotate about an axis at a substantially fixed distance from a longitudinal axis of the respective module of which they form part. For example, one or more rollers may be provided such as wheels, caterpillar tracks or other suitable roller arrangements. The rollers may be arranged such that the robot 100 may crawl along the pipeline 101 with the rollers contacting only a lower internal surface area of the pipeline 101.

In the embodiment of FIG. 1 the rollers of the tractor module 110 are configured to be driven by electric motors that are powered by means of an electrical powerline carried by an umbilical cable 100C. The umbilical cable 100C runs along a length of the robot 100 along a conduit provided through each module.

The tractor module 1 0 also carries an onboard robot control portion 115. The onboard control portion 115 includes a computing device that is in data communication via a data line carried by the umbilical cable 110C with a main or primary interface module 1 10PM external to the pipeline 101 as shown schematically in FIG. 2. The primary interface module 1 10PM is connected to a secondary interface module 110SM which in the present embodiment is provided by a portable computing device having a keyboard and display screen. The secondary interface module 110SM allows a user to control the primary interface module 10PM to send electrical control and power signals, and supply compressed air at a required pressure, to the robot control portion 115. By means of the secondary interface module 110SM an operator may control the tractor module 110 to cause the robot 100 to move in a forward and reverse direction within the pipeline 101 and to operate each of the drill module 130, insertion module 140 and leak test module 150 to install a pipe fitting allowing connection of a consumer service pipeline to a main pipeline. The robot 100 may also be controlled to leak-test the newly connected consumer service pipeline. It is to be understood that, in the event the robot becomes immobilised for any reason within the pipeline 101 , the robot may typically be retrieved by pulling on the umbilical cable 1 10C.

For brevity, the drill module, the insertion module and the leak-test module will not, and need not, be described in further detail here, but it is to be understood that they may each have any appropriate or desired construction, configuration and operation as required of the apparatus or its intended use, either in terms of known or novel principles and/or features.

However, for the purpose of the present invention reference is now made to FIG. 3, which shows the pneumatic supply module 120 of the robot 100 in isolation. The pneumatic supply module 120 is shown here in somewhat simplified form without its support arms 120R. Although the robot 100 is shown in FIGS. 1 and 2 as comprising a single pneumatic supply module 120, which preferably means that the operational modules that require compressed air therefrom for their actuation all operate with substantially the same working pressure of the compressed air source, it is possible in other embodiments for a plurality of pneumatic supply modules 120 to be provided in the robot, e.g. at spaced apart locations, in order to provide a plurality of compressed air sources for the respective modules, possibly for example with one or more of the pneumatic supply modules 120 providing compressed air at a different working pressure from one or more others of the pneumatic supply modules 120.

Any one or more of the drill module, insertion module, leak test module, and/or indeed additionally either or both of the tractor module and/or trailer module, constitute respective operational devices of the overall robot 100, and at least one or more of these modules comprise(s) actuation means which triggers or controls its operation {in accordance with known principles and constructions per se) by use of compressed air. It is however to be understood that any of these operational modules may instead operate using a hydraulic (i.e. liquid-based) system instead of a pneumatic (i.e. gas-based) one. The supply of compressed air to the appropriate module(s) that require it is provided by the pneumatic supply module 120, of which FIG. 3 shows one only, which in accordance with the invention is carried onboard the robot 100 as one of its modules. Thus the pneumatic supply module 120 is thus carried with the remainder of the robot 100 as it moves along the pipeline. Because of the much closer proximity of the compressed air supply to the operational module(s) that require it for their actuation, it is possible to obtain significantly faster response times when it is desired to deliver an amount of the compressed air to a given module to actuate it. It also enables the umbilical cable 100C to be lighter and less complex in construction, making it easier and more energy efficient for the robot to propel itself along the pipeline and perform its various operational functions, especially as it moves along the pipeline at increasingly greater distances from the ground-based main control station or primary interface module 1 10PM (FIG. 2).

The pneumatic supply module 120 comprises a reservoir for holding a supply of compressed air, which reservoir is in the form of a tank 200, such as part-cylindrical in shape, as illustrated in FIG. 4 (but inverted in comparison with its orientation in FIG. 3). In a representative currently preferred embodiment, the tank 200 may typically have a volume of the order of about 160000 mm ³ . The tank 200 has side and end walls of a sufficiently strong and rigid material, e.g. metal or a plastics material, to enable it to maintain its own stable shape whilst withstanding the pressure of fluid to be stored within it. Examples of suitable materials and widely available in the art. The elongate side of the cylinder opposite a major cylindrical portion thereof may advantageously be formed with a somewhat flattened or concave shape, such as at 202, in order to accommodate electric cabling (e.g. signal cabling) and/or air supply tubes or lines that may need to pass longitudinally along the robot for linking the pneumatic supply module 120 to the other module(s) to which it supplies compressed air. A suitable number, shape and size of cable retaining clips 260 may be provided to secure such electric or pneumatic cabling or tubes in place, so they do not interfere with passage of the robot along the pipeline or the correct operation of any of its operational modules.

At each end of the tank 200 is a manifold 220a, 220b which houses an arrangement of input/output ducts 210, each optionally with a respective connection nipple, to enable all the various and appropriate pneumatic connections to be made via tubing (not shown) that connects the pneumatic supply module 120 to the one or more operational modules that require the compressed air source. Those connections may, to the extent necessary or appropriate e.g. depending on the identity and overall arrangement and pneumatic requirements of the various operational modules, may be via one or more control sections 230, 240, e.g. one located at each end of the tank 220, within which the necessary connections are made. The control section(s) 220a, 220b may also house any necessary valves or pressure regulating device(s) for controlling or providing a selected output air pressure to suit the requirements of any given operational module. In any given example embodiment, the precise physical arrangement of connection(s) and/or valve(s) and/or pressure regulating device(s) within each such control section 220a, 220b may vary as the overall arrangement of modules, including the pneumatic supply module 120, demands, the practising of which will be well within the purview of persons skilled in the art. At least one of the control sections 220a, 220b may also house a connection arrangement for linking the tank, via an inlet thereof, to an external source of pressurised air, e.g. via the umbilical cable 100C, for the purpose of charging the tank with a supply of compressed air as or when required. That external charging source may in some embodiments be at a charging pressure in excess of any working pressure of any outlet of the tank 200, in order to reduce charging times, although in this case appropriate pressure regulating device(s) may be required in the relevant output feed(s) supplying compressed air to the relevant operational module(s) in order to deliver an appropriate air supply thereto at the correct respective working pressure. Any charging of the tank 200 may thus be made intermittently, as or when required, which may be either while the robot is within the pipeline and doing its job(s) or when it has been removed therefrom upon completion of a job.

It is to be understood that the gas contained in the tank 200 and supplied to the various operational modules may be a gas other than air, depending on the design of the relevant module(s) which is/are to be supplied by it. It is furthermore possible within the scope of the invention for the robot to be provided with a plurality of different supply modules 120, which may for example each contain a different gas for supply to an appropriate operational module that requires it for its actuation or operation. Further alternatively, a plurality of different supply modules 120 may even constitute respective supplies of one or more pneumatic fluids and one or more hydraulic fluids, again where different operational modules require same for their actuation or operation.

Throughout the description and claims of this specification, the words "comprise" and "contain" and variations of the words, for example "comprising" and "comprises", means "including but not limited to", and is not intended to (and does not) exclude other moieties, additives, components, integers or steps.

Throughout the description and claims of this specification, the singular encompasses the plural unless the context otherwise requires. In particular, where the indefinite article is used, the specification is to be understood as contemplating plurality as well as singularity, unless the context requires otherwise.

Features, integers, characteristics, compounds, chemical moieties or groups described in conjunction with a particular aspect, embodiment or example of the invention are to be understood to be applicable to any other aspect, embodiment or example described herein unless incompatible therewith.