[0002] It is generally a difficult and costly procedure to lay fiber optic cable in developed regions where infrastructure such as roads, utilities, and the like are already in place. For example, it can be costly to obtain the requisite right-of-ways or easements from numerous different property owners. It can also be very costly to dig trenches to lay fiber optic cable. In addition, it is also often necessary to obtain the approval of various state and local government agencies before such work can begin. This can significantly increase the overall cost and delay the completion of the installation.

[0003] Existing gas pipelines have been considered as one potential conduit that can be used to carry fiber optic cable. By using existing gas pipelines, there is no need to obtain numerous right-of-ways or easements, since the fiber optic cable simply resides within the pipeline. In addition, long trenches do not have to be dug to lay the fiber optic cable. However, using gas pipelines as a route for fiber optic cable typically requires that sections or all of the pipeline be shut down for an extended period of time for installation of the cable. Even if the gas pipeline is not completely shut down, existing techniques interrupt the normal flow of gas.

[0004] Accordingly, there is a need for a relatively quick and inexpensive systems, tools, and methods of installing fiber optic cable, or conduit which can be used to house the cable, into existing pipelines such as natural gas pipelines.

[0005] Natural gas utilities are constantly replacing and upgrading their distribution pipeline systems. These efforts are undertaken for a variety of reasons, including situations when the pipe's useful life is reached, when demand requires that additional supplies be distributed or when improved pipeline materials become available. In many cases, a lower pressure pipeline system can be upgraded to a higher- pressure system by installation of higher pressure-rated or newer pipe with a substantially smaller diameter.

[0006] In urban areas, replacement or upgrade of distribution systems is especially problematic since open trenching costs are very high and public disruption significant. Alternatives to trenching include various methods for insertion of"casing" into the existing pipelines. This process, while generally more acceptable than trenching, is also costly. Many casing methods require de-pressurization of the pipeline while the casing is being installed. This is costly to the utility and can disrupt service to substantial numbers of customers for extended time periods.

[0007] Accordingly, improved methods and systems are needed for replacing and upgrading existing pipeline systems.

[0008] Various tools and techniques have successfully been used in the past to stop flow of liquids or gases in pipelines. These tools are typically used to temporarily stop flow, to allow a downstream section of pipeline to be inspected, repaired, changed, or otherwise serviced. Such stopping or sealing tools are often used in emergency

situations to stop flow within a localized section of pipeline, when flow cannot be quickly or easily stopped using existing valves in the pipeline. These tools are also used for planned operations or maintenance. In pipelines made of materials such as polyethylene, or similar plastics which can be deformed without damage, squeeze or pinch tools have been used to temporarily stop flow. These types of tools squeeze or pinch the pipeline flat to stop flow. When removed, the pipeline returns to its original or near original typically round shape, allowing flow to resume. For rigid or <BR> <BR> non-deformable pipelines, made of e. g. , steel or iron, various stopping or plugging tools have been used. Some of these stopping or plugging tools can also be used with plastic pipe if the pinch method is not desired. With these tools, typically an opening is cut or drilled into the pipeline through a pressure housing. The stopping tool then installs a plug or similar stopping element into the pipeline to stop flow. The stopping element is removed when service is complete, allowing flow to resume. Leakage of gas or liquid from the pipeline during the stopping operation is minimized or eliminated via the pressure housing.

[0009] Placing fiber optic cable or conduit within existing natural gas pipelines has recently become much more viable, with the development of systems and methods for installing the cables while the pipeline remains in service. See for example International Patent Application PCT/US/01/31468. Especially in urban areas where trenching to lay cable is difficult, time consuming, and costly, and where virtually all buildings are already connected to a natural gas pipeline network, the use of fiber optic cable within natural gas pipelines has many advantages.

[0010] However, existing tools and techniques used for stopping flow in a natural gas pipeline are not usable for pipelines containing a cable. With the cable or conduit laying on the bottom of the pipeline, the stopping or sealing elements currently in use cannot achieve an effective seal within the pipeline (since the flow area inside the pipeline is no longer a circular cross section). In addition, regardless of the lack of effective sealing characteristics, use of existing stopping or sealing tools and techniques in pipelines containing a cable involves significant risk of crushing, severing or otherwise damaging the cable.

[0011] Accordingly, with the introduction of cable into pipelines, there is a need for flow stopping tools and techniques, which are compatible with a cable or conduit in the pipeline.

Brief Statement of the Invention [0012] In a first aspect of the invention, an extractor system for installing a cable or conduit into a pipeline includes a receiver assembly and a nose assembly. The nose assembly has a nosepiece and the receiver assembly has a latching mechanism for latching onto the nosepiece. The receiver assembly also preferably has a guide section for guiding the nosepiece into the receiver assembly. In an alternative aspect, the nose assembly has a u-joint to better facilitate engagement between the nose piece and the receiver assembly. The extractor system simplifies and expedites routing of a cable or conduit in a pressurized pipeline.

[0013] In a second aspect of the invention, a duct rod assembly for use in installing a cable or conduit into a pipeline includes a duct rod, a nose piece on the duct rod, a gland body having a seal, with the duct rod extending through the seal in the

gland body. A receiver assembly includes a latching mechanism for engaging onto the nose piece, when the nose piece and receiver assembly are engaged together. The gland body may optionally further include a threaded section adapted to engage onto a pipeline fitting.

[0014] In a third aspect, an extractor system for use in installing a cable or conduit into a pipeline includes an end plug attached to the cable or conduit and an end nose having a coupling feature. A coupler has a receptacle adapted to couple onto the end plug. The end plug preferably has a rounded end nose, a conical guide collar, and a coupler groove between the end nose and the guide collar. A conical guide may be provided on the receptacle to engage with the conical guide collar on the end plug.

[0015] In a fourth aspect, an extractor tool for extracting an end fitting through a pressure seal during installation of a cable or conduit into a pressurized gas pipeline includes an extractor tube, a handle attached adjacent a first end of the extractor tube, a lock rod axially displaceable within the extractor tube, and a tube collar section at a second end of the extractor tube. A socket is axially displaceable within the tube collar section. The socket is attached to the lock rod. Retainers in the socket move to engage an end fitting on a cable, conduit, or duct rod, when the end fitting is moved into the tube collar section.

[0016] In a fifth aspect a receiver assembly for engaging and extracting an end fitting on a cable, a conduit, or a duct rod, includes a pull bar, handle attached adjacent a first end of the pull bar, and a socket extending into a sleeve attached to a second end of the pull bar. An insert is axially displaceable within the socket and biased into a first position by an insert spring. A sleeve spring urges the sleeve away from the second end

of the pull bar and over the socket. A locking element is provided between the sleeve and the socket. A pawl is pivotally attached to the pull bar and moveable from a first position, wherein the sleeve is positioned at least partially over the pawl, to a second position, wherein the pawl locks the sleeve against movement towards the first end of the pull bar. These components and tools provide improvements in installing cable or conduit in a pressurized pipeline.

[0017] In a sixth aspect, a method for installing a cable or conduit into a pipeline includes the steps of routing a first line having a first end fitting into the pipeline, from a first location. A second line having a second end fitting is routed into the pipeline from a second location, until the second end fitting contacts the first end fitting, at an intermediate position within the pipeline, between the first and second locations. The first end fitting is then engaged with the second end fitting. The first line is pulled back until the second end fitting is adjacent to the first location. The end fittings may be an end plug and a mating receptacle, or they may be grappling fittings or components, or spiral fittings or components. Various equivalent end fittings which can engage and hold onto each other, while the lines are pulled through the pipeline, may be used. This method substantially doubles the pipeline routing length of conventional duct rod or conduit pushing methods, since two lines are routed or pushed towards each other from opposite ends of a pipeline segment.

[0018] In a seventh aspect, a method of installing a pipe inner duct into a pressurized pipeline includes the step of attaching a first air or pressure lock housing to the pressurized pipeline at a first location. A second air or pressure lock housing is attached to the pressurized pipeline at a second location. Duct rod or other translating

member is preferably fed into the pipeline through a seal at the first location. The duct rod is pushed or routed to the second location. A pipe inner duct is attached to the duct rod, at or adjacent to the second location, either inside or outside of the pipeline. The duct rod and the pipe inner duct are then pulled back to the first location and routed out of the pipeline. This method allows a new pipeline of smaller diameter to be installed <BR> <BR> into an existing (e. g. , buried) pipeline of a larger diameter, without interrupting flow through the pipeline.

[0019] An eighth and separate aspect of the invention includes the steps of attaching a first fitting to the pressurized pipeline at a first location. A first valve is attached to the first drilling fitting. A cutting or drilling tool is attached to the valve, and sealed against the valve. The valve is opened. A pipe cutter of the cutting tool is extended through the open valve to cut or drill a hole into the pressurized pipeline through the first fitting. The fitting and pipe cutter are preferably perpendicular to the pipeline to better facilitate the drilling operation. The cutter is withdrawn and the valve is then closed. The cutting tool is preferably removed.

[0020] A first air lock housing is installed on the first valve. The valve is opened and the pressure is equalized between the first air lock housing and the pressurized pipeline. A guide ball or similar duct rod end guide is optionally attached onto the end of the duct rod using a first manipulator in the first air lock housing. A second fitting is attached to the pressurized pipeline at a second location. The exit port of the second drilling fitting is sealed. A second valve is attached to the second fitting.

A cutting or drilling tool is attached and sealed against the valve. The valve is opened.

A cutter is extended from the cutting tool and a hole is cut or drilled into the pressurized

pipeline through the second fitting. The cutter is withdrawn and the valve is closed. A second air lock housing is installed on the second drilling fitting. The second valve is opened and pressure is equalized.

[0021] A duct rod or other translating member is pushed along inside of the pressurized pipeline to the second fitting. At the second fitting, the guide ball or other rod end guide, if any, is removed from the duct rod, for example using a second manipulator. The duct rod is attached to a pipe inner duct. The duct rod and the pipe inner duct are pulled back through the pipeline. Alternatively, once the duct rod is routed between the first and second air lock housings, the pipe inner duct can be attached to duct rod outside of the first air lock housing and the duct rod can be pulled forward from the second air lock housing, to route the pipe inner duct through the pipeline. The pipe inner duct then provides a new pipeline within the existing pipeline.

[0022] This method allows for the installation of a new inner pipeline within an existing pressurized pipeline, such as a gas pipeline, without requiring any shutoff or interruption in service. In addition, no bypass pipeline is needed to maintain service to customers connected to the pipe section where the new inner pipeline is being installed.

The methods are suitable for both metal and plastic pipelines. Excavation or trenching to replace the existing pipeline or to lay a new pipeline is avoided.

[0023] Tools and techniques are also provided for stopping flow in a pipeline containing a cable. The tools may be used on pipelines above ground, or with minimum trenching and exposure of buried pipelines. The tools provide an effective seal within the pipeline, stopping flow, without damaging the cable in the pipeline. The tools may

be used at any location along pipeline. Generally, each tool seals against the inside round walls of the pipeline, and also around the outside of the cable.

[0024] A tool for pinching off flow of gas through a deformable or plastic pipeline includes an actuator on an armature. The actuator moves an upper element or plate towards a lower element or plate. Displacement members on the lower plate help to guide the cable within the pipeline into a recess in the lower plate. This allows the pipeline to be squeezed flat to stop flow, without crushing the cable. The displacement members are preferably rollers or lever arms. The displacement members are advantageously urged into an up or extended position by springs.

[0025] A tool for sealing off gas flow, in a rigid (e. g. , steel) pipeline, or in a deformable or plastic pipeline containing a cable, has a seal ring on a handle. A linkage on the handle drives seal lips on the seal ring to engage around and seal against the cable within the pipeline. The outside circular edges of the seal ring seal against the inside walls of the pipeline. Preferably, the drive linkage includes jaws engaged with the seal lips. A rod advantageously extends through the handle and is connected to the jaws, for remote operation of the jaws.

[0026] A stopper tool for use in a pipeline containing a cable or conduit has first and second plates pivotably attached to a center plate. A resilient seal ring overlies the first, second and center plate. A linkage pivots the first and second plates from an open position, where the first and second plates are oriented at an angle to the center plate, to a second position where, the first and second plates generally lie within the same plane as the center plate. The tool is installed into the pipeline with the plates in the first

position. Once appropriately located within the pipeline, the first and second plates are pivoted into the second position, creating a seal within the pipeline.

[0027] A pipeline flow stopper tool has a resilient plug including first and second lips positioned to fit over a cable within a pipeline. As the plug is pushed into the pipeline, the plug deforms and seals against the pipeline walls. The first and second lips extend around and under the cable, forming a continuous seal around the cable within the pipeline.

[0028] Other and further objects and features will become apparent from the following detailed description. The invention resides separately as well in subcombinations of the assemblies, components, tools, fittings and steps described. The fittings, components, and tools may also be provided as a kit. Each of the stopping tools <BR> <BR> described is intended for use in a pipeline having a specific inside diameter of e. g. , 5- 100 cm. Consequently, typically tools including any of the aspects described above will be available in a range of sizes. The tools are also intended for use with a cable or conduit of a known and specified diameter within the pipeline. While the systems, components, tools and methods described are preferably used with pressurized gas pipelines, they may also be used with other pipelines as well.

[0029] It is an object of the invention to provide methods and systems for installing fiber optic or similar cable or conduit into existing pressurized pipelines without interrupting the flow in the pipeline.

[0030] It is also an object of the invention to provide a method and system for <BR> <BR> installing a pipe inner duct into existing pressurized (e. g. , gas) pipelines without

interrupting the flow in the pipeline, to provide a new pipeline within the existing pipeline.

[0031] It is also an object of the invention to provide tools and techniques for stopping flow within a pipeline containing a cable or conduit.

BRIEF DESCRIPTION OF THE DRAWINGS [0032] Figure 1 is a schematic diagram of a first embodiment of a mid-pipeline connection conduit installation.

[0033] Figure 2 is a schematic diagram of a second embodiment of a mid-pipeline connection conduit installation.

[0034] Figure 3 is a schematic diagram of a third embodiment of a mid-pipeline connection conduit installation.

[0035] Figure 4 is a side view of the self joining duct rod ends shown in Figure 2.

[0036] Figure 5 is a section view taken along line 5-5 of Figure 4.

[0037] Figure 6 is a perspective view of alternative design self joining duct rod ends.

[0038] Figure 7 is a schematic illustration of a coupler leader for use in performing methods similar to those shown in Figure 1.

[0039] Figure 8 is a schematic diagram of a system and method for installing a gas pipe inner duct within a pipeline.

[0040] Figure 9 is an enlarged schematic diagram of the system and method shown in Figure 8.

[0041] Figure 10 is a perspective view of a pipeline in a trench, with a cable within the pipeline.

[0042] Figure 11 is a front view of a tool for use with deformable or collapsible pipelines, such as polyethylene.

[0043] Figure 12 is a top view of the tool shown in Figure 11.

[0044] Figure 13 is a side view of the tool in shown in Figure 11.

[0045] Figure 14 is a section view of the top plate assembly shown in Figure 11.

[0046] Figure 15 is a section view of the bottom plate assembly shown in Figure 11.

[0047] Figure 16 is a top view of the bottom plate assembly shown in Figures 11 and 15.

[0048] Figure 17A is a side view, in part section of the bottom plate assembly shown in Figures 11 and 15, with the pipeline shown before pinching.

[0049] Figure 17B is a side view, in part section, of an alternative tool, similar to the tool shown in Figure 17A, and with top and bottom rollers.

[0050] Figure 18 is a view similar to Figure 17, shown with the pipeline pinched closed.

[0051] Figure 19 is a section view of an alternative pipeline pinching tool.

[0052] Figure 20 is a left side view of another tool for stopping flow in a pipeline containing a cable.

[0053] Figure 21 is a partial section view of the tool shown in Figure 20.

[0054] Figure 22 is a right side view of the tool shown in Figures 20 and 21, with the seal ring removed for purpose of illustration.

[0055] Figure 23 is a front view of the front plate of the tool shown in Figure 21.

[0056] Figure 24 is a side view thereof.

[0057] Figure 25 is a front view of the rear plate shown in Figures 20 and 21.

[0058] Figure 26 is a section view taken along line 26-26 of the Figure 25.

[0059] Figure 27 is a front view of the seal ring shown in Figure 21.

[0060] Figure 28 is a section view taken along line 19-19 of the Figure 27.

[0061] Figure 29 is a top view of the seal ring shown in Figure 27.

[0062] Figure 30 is a front view showing the tool of Figure 21 in an open position.

[0063] Figure 31 is a side view showing the installation of Figure 30.

[0064] Figure 32 is a top view thereof.

[0065] Figure 33 is a front view showing the tool of Figure 30 in the closed position.

[0066] Figure 34 is a top view of an alternative flow stopping tool, for use in a rigid pipeline containing a cable, and showing the tool in an open position.

[0067] Figure 35 is a top view of the tool shown in Figure 34, in the closed position.

[0068] Figure 36 is a front view of the tool shown in Figure 35.

[0069] Figure 37 is a side view of the tool shown in Figures 35 and 36.

[0070] Figure 38 is a front section view of a stopper assembly of an other tool for use in stopping flow within a pipeline containing a cable, and showing the stopper assembly in an unsealed position.

[0071] Figure 39 is a front view of the tool shown in Figure 38, in a closed or sealed position.

[0072] Figure 40 is a side view showing installation of the stopper assembly shown in Figures 38 and 39.

[0073] Figure 41 is a side view of the plunger shown in Figures 38,39 and 40.

[0074] Figure 42 is a side view of the plug shown in Figures 38,39 and 40.

[0075] Figure 43 is section view of a cable in a pipeline having an access opening within a pressure lock housing on the pipeline.

[0076] Figure 44 is a schematic section view of the pipeline of Figure 43, showing installation of a crescent strip or plate around the cable.

[0077] Figure 45 is section view of the pipeline of Figure 44 with the crescent strip fully installed.

[0078] Figure 46 is a schematic section view of the pipeline of Figure 45 with a deflated airbag installed in preparation for plugging the pipeline to stop flow.

[0079] Figure 47 is a schematic section view of the pipeline of Figure 45 with the airbag now inflated and plugging the pipeline to stop flow.

[0080] Figure 48 is front view of the crescent strip shown in Figures 44-47.

[0081] Figure 49 is bottom view of the crescent strip shown in Figure 48.

DETAILED DESCRIPTION [0082] Figures 1-3 schematically show mid-pipeline connection methods. First and second translating members 802 and 804, such as a duct rods or conduits, are routed towards each other within the pipeline 30 from first and second entry points 806 and 808. The translating members have end fittings 812 and 814 designed to engage and

hold onto each other. In the embodiment shown in Fig. 2, the end fittings 812 and 814 are grappling fittings 816 having rear facing flanges or fingers 818.

[0083] As shown in Figs. 4 and 5, the end fittings are moved past each other at a mid point 810 in the pipeline. The translating members are then pulled back. The flanges 818 then engage into each other. The first translating member is then pulled back to the first entry point, pulling the second translating member with it. The second translating member is optionally pushed as well. The first and second translating members can then be used to route a cable or conduit through the pipeline from the first entry to and out of the second entry point. This mid point connection method effectively doubles the length of pipeline that can be traversed using duct rod, in contrast to pushing duct rod from one end only. Of course, the mid point where the translating member meet and join each other within the pipeline may be at virtually any location between the first and second entry points. However, typically, if the first and second translating members have similar push through distance limits, the mid-point will be about equally distant from the first and second entry points.

[0084] By measuring the length of translating member or duct rod pushed out (which many pushing machines 860 can automatically do), the machine operators know the positions of the end fittings within the pipeline. When the end fittings are approaching each other, their movement can be slowed down. Depending on the type of end fittings used, they can be pushed towards or past each other, and optionally then slowly pulled back, until they engage or lock together. An increase in the force needed to pull back one translating member indicates a positive engagement, as the machine <BR> <BR> 860 pulling back is now pulling twice the length of e. g. , duct rod. Generally, to perform

the actual engagement of the end fittings, one end fitting is stopped and remains still within the pipeline. The other end fitting is then advanced, to engage with the stationary end fitting.

[0085] The end fittings 812 and 814 can have various designs, so long as they can engage and hold each other against the pull back force needed to extract the translating members from the pipeline. Various latching, hooking, catching, winding, adhering, etc. techniques may be used. As shown in Fig. 1, the end fittings 812 and 814 may include an end nose fitting and a socket fitting. Alternatively, the translating member fittings can combine together various latching mechanisms that increase the chances of a successful coupling. For example, as shown in Fig. 2, the fittings can be <BR> <BR> constructed with a nose and socket fitting design. , as well integrated as latching mechanisms as shown in Fig. 5. This dual design provides two mechanisms or modes of attachment, thus increasing the likelihood of a successful coupling. As shown in Fig.

6, the end fittings 812 and 814 may include coil elements 820 and 822. Turning the translating members as they advance (which some duct rod drivers 860 can automatically do) causes the coil elements 820 to engage and lock into each other.

Either translating member can them be pulled back to its entry point to complete the cable or conduit installation process. The end fittings can be installed and removed onto the duct rod 802 and 804, without de-pressurizing the pipeline, as described in International Patent Application No. PCT/US01/31468.

[0086] The mid-pipe coupling methods can be achieved typically without manual manipulation at the point of connection. The latching or nose socket

mechanisms are designed to couple the translating members when they are pulled past each other in close proximity or pushed together head-on, respectively.

[0087] As shown in Fig. 7, a coupling leader 900 has a rigid front end fitting or rod 902 attached to a coupling body 904 by a flexible link, such as a cable or wire 906.

The flexible link 906 may extend into and through the coupling body 904, to a rear fitting 908. The coupling body 904 has a covering 910 to provide rigidity, and to also provide a cylindrical surface to seal against during insertion/extraction through seal fittings into a pressurized pipeline. The rear fitting 908 attaches to a translating member, such as a duct rod. The coupling leader 900 may be used in front of the types fittings shown in Figs. 4-6, to better facilitate alignment and engagement of translating members in performing mid-point connection methods. Alternatively, the coupling leader 900 can be used alone at the leading end of one translating member, with the other translating member having a similar leader, but having a receptacle to receive and couple with the front end fitting 902.

[0088] In use, the coupling leader 900 tends to align itself on the pipe axis at the pipe bottom as the translating member is pushed or pulled through the pipe. This alignment helps to enable consistent coupling of the end fittings without manual manipulation at that point.

[0089] For certain applications, it may be useful to access the end fittings 812 and 814 at the joining point or mid point 810. As shown in Fig. 3, an air lock housing, such as housing 830 may be attached to the pipeline at or near the mid point. One or more manipulators such as manipulators 805 can then be used to assist in attaching the

end fittings 812 and 814 together, as described in International Patent Application No.

PCT/US01/31468.

[0090] Turning now to Figures 8 and 9, in a method for installing a new pipeline into an old or existing pipeline techniques, an inner new pipeline or gas pipe inner duct 1000 is routed out of the pipeline 30 at a first fitting 20, or a similar equivalent fitting.

If fiber optic conduit 1004 is included within the gas pipe inner duct 1000, the conduit 1004 is branched out at fiber optic conduit fittings 1006. The conduit 1004 can then run <BR> <BR> into buildings, switches, etc. , or back into the gas pipe inner duct 1000, by passing the gas service T 1008. The gas service T 1008 connects a secondary or building service pipeline 1010 into the gas pipe inner duct 1000.

[0091] The gas pipe inner duct 1000 will typically be standard polyethylene pipe certified for use in natural gas systems. The gas pipe conduit is installed via direct insertion; by duct rods; or by using mid-pipe coupling techniques.

[0092] One advantage of this system is that gas pipe inner duct 1000 service T's and/or fiber optic conduit and access fittings can be installed easily, prior to pressurization of the gas pipe inner duct 1000, at the point the gas pipe inner duct exits the pipeline being upgraded. As this can be accomplished before pressurization of the gas pipe inner duct 1000, the processes for installing the fittings and inserting the fiber conduit can be conducted quickly. This system may be used to provide a pipeline upgrade, or a fiber optic line installation, or both. After all of the connections are made, as shown in Figures 8 and 9, the gas pipe inner duct 1000 may be pressurized with natural gas, and the existing obsolete pipeline around it can be depressurized and removed from service.

[0093] Turning now to pipeline shutoff tools, as shown in Figure 10, a pipeline 30 containing a conduit or cable 32 rests on the bottom 35 of a trench 34. The term conduit or cable means a conduit, cable, duct, pipeline, or other lumen, which may or may not contain optical fibers, copper wires or other lines.

[0094] Turning to Figures 11,12 and 13, where the pipeline 30 is a squeezable or deformable material, such as polyethylene, a pincher tool 50 may be used to stop flow within the pipeline 30, without damaging the cable 32 contained in the pipeline 30.

[0095] As shown in Figure 11, the pincher tool 50 has an armature 52 including side arms 60. A top plate 56 is vertically movable along guide rails 58 on the armature side arms 60. An actuator 54 attached to the armature 52 is joined to a spring housing 64 on the top plate 56. Referring to Figures 2 and 5, a centering plate 62 having side lobes 63 is attached to a spring plate 65 via plate bolts 67. The centering plate 62 is also attached to center plunger 69 by a plunger bolt 71. A centering plate spring 66 surrounding the center plunger 69 is attached the spring plate 65, and to the spring housing 64. The centering plate 62 according can move up into a plate recess 68 in the top plate 56, as force acting on the centering plate 62 compresses the spring 66.

[0096] Turning to Figures 15,16, and 17A, a pinch plate 86 on the bottom plate assembly 70 has a centrally located plate recess 88. Left and right side roller assemblies 73 are spaced apart on opposite sides of the plate recess 88. The roller assemblies 73 are preferably identical, and the bottom plate assembly 70 is preferably symmetrical side to side about the centrally located plate recess 88. The following description of the right side roller assembly 73 shown in Figure 15 applies as well to the left side roller assembly in Figure 15.

[0097] A roller 74 is rotatably supported on a roller arm 76 pivotably attached to the pinch plate 86 on a roller arm pivot pin 96. A roller link 78 extends from the end of the roller opposite the roller 74 to a spring hub 80. A roller spring 82 around the spring hub 80 is contained on or in the bottom plate assembly 70 by a spring stop 84. The spring 82 urges the spring hub 80 to the left in Figure 15, holding the roller 74 in an upright position. A stop nut 94 on a roller arm stop 92 is adjustable to set the up position of the roller 74. Optionally, a single spring acting on both rollers may be used.

The roller assemblies 73 can also be used on the top plate 56, as shown in Figure 17B, in place of the centering plate 62.

[0098] The tool 50 is used to pinch the pipeline 30 closed, to stop flow (e. g. , of natural gas) through the pipeline. This allows a down stream section of the pipeline to be opened up for inspection, maintenance, service, expansion, etc. If the pipeline 30 is buried, a hole or trench 34 is excavated around the pipeline. The bottom plate assembly 70 is then separately installed under the pipeline, with the pipeline resting on the rollers 74. The armature 52 is then brought down over the pipeline. The centering plate 62 in the extended position shown in Figure 2. The bottom plate assembly 70 is connected to the armature 52 by plate bolts or posts 72. The tool 50 and pipeline 30 are then position as shown in Figure 11.

[0099] The actuator 54 is extended, driving the top plate 56 down towards the bottom plate assembly 70. The actuator 54 may be a hydraulic or pneumatic actuator.

Alternatively, the actuator 54 may be a manually operated actuator, such as a jacking screw, hand pumped hydraulic jack, etc. The size, material and wall thickness of the pipeline 30, which determines the compressive force needed to squeeze the pipeline

shut, will also determine, at least in part, the type, size and number of actuators needed.

Various size or models of tools are preferably used for different size pipes. Each model of tool preferably has pressure relief and bar stops to prevent over-compression, as is well known in the pipeline tool industry.

[00100] As the top or pinch plate 56 is driven down by the actuator 54, the pipeline 30 begins to squeeze closed. The centering plate 62 moves up into the spring housing 64, compressing the centering plate spring 66. The rollers 74 begin to move down, from position A, to position B, in Figure 17A. As the pipeline 30 is pinched, the lobes 63 of the centering plate 62 compress the pipe such that the conduit 32 is urged towards the vertical center line C of the pipeline 30. The rollers 74, acting from below, similarly urge the conduit to the center position, so that when the pipeline 30 is fully pinched flat, the conduit rests in the plate recess 88 and is not damaged, and full flow stoppage is achieved. The tool in Figure 17B operates in a similar way. The tools in Figures 17A and 17B both automatically center the conduit/cable no matter where the conduit is laying in the pipe. Centering the conduit allows for gas shut off without damaging the cable/conduit.

[00101] Figure 18 shows the pipeline 30 completely pinched closed. The cable 32 within the pinched pipeline 30 rests within the plate recess 88 on the pinch plate 86.

The rollers 74 are flush with the top surface of the pinch plate 86.

[00102] The pipeline 30 remains in the pinched position shown in Figure 18, with gas flow through the pipeline stopped, until after the downstream pipeline operations <BR> <BR> (inspection, maintenance, service, repair, etc. ) are completed. The actuator 54 is then reversed, lifting the top plate 56 up. The rollers 74 return to the up position shown in

Figure 11. The pipeline 30 gradually returns to its original round shape, allowing unimpeded gas flow. The plate bolts 72 are removed and the armature 52 withdrawn.

The bottom plate assembly 70 is removed from underneath the pipeline 30. The excavation or trench 34 around the pipeline 30 is then filled in.

[00103] Figure 19 shows a pipeline pinching tool 100 similar to the tool 50 described above. However, the tool 100 has pipeline levers 102 instead of the rollers 74. The levers 102 are spring biased into the up position shown in Figure 19 by springs 108 acting outwardly on spring hubs 106 and lever links 104. The pipeline levers 102 act as displacement members, in the same way as the rollers 74 described above. Other forms of displacement members, including single members such as troughs, v-channels, etc. may also be used.

[00104] Existing tools currently in use for pinching pipelines without a conduit or cable have an armature 52, an actuator 54, and flat upper and lower plates. For use with pipelines containing a conduit or cable, these types of tools can be retrofit with plates having the cable centering features shown in Figure 11-18. The plates 56 and 70 (along <BR> <BR> with the components on them, as shown e. g. , in Figures 14 and 15) can be provided as inserts or kit parts for use in these known pipeline squeezing tools. When provided as inserts, the features shown in Figures 11-18 can be used with commercially available pinch tools or machines. The advantage of this approach primarily stems from the benefit of using existing machines already owned by the pipeline operator. Training and documentation for existing equipment can largely be used as is, thus reducing overall expense of the operation. Furthermore, manufacturing costs of the inserts are less compared to fabrication of a custom machine used specifically for this purpose. Since

the Insert design automatically centers the conduit/cable for an advantageous closure of the pipe with damage to the conduit or cable, the existing procedures used with existing pinching machines can also be used when such machines are fitted with the inserts having cable centering features or devices.

[00105] Turning now to Figs. 20,21 and 22, a tool 150 primarily intended for stopping flow within a rigid pipeline (but also be usable in plastic pipelines), has a thrust bar 162 attached to a handle 152 by a thrust collar 160. A pipe plug assembly generally designated as 164, is attached to the lower end of the handle 152. The pipe plug assembly has a back plate 174 attached to the handle 152 by a handle bracket 210. A front plate 166 holds a resilient seal ring 190 against the back plate 174. As shown in Figs. 23 and 24, the front plate 166 has a conduit recess 170, a bevel edge 168, and mounting holes 172. Referring to Figs. 25 and 26, the back plate 174 also has a conduit recess 184 generally matching the size and shape of the conduit recess 170 in the front plate 166. The back plate 174 includes a rod slot 176, plate mounting holes 178 matching the pattern of the mounting holes 172 in the front plate 166, pivot pin holes 182, and bracket mounting holes 180.

[00106] Referring to Figs. 27,28 and 29, the seal ring 190, preferably made of a resilient material, such as rubber, has a tapered outer cylindrical wall 196 dimensioned to seal with the inside walls of the pipeline 30. A split conduit opening or recess 192 extends through the seal ring 190, preferably at a bottom center or 6 o'clock position.

Seal lips 200 at the bottom of the split conduit opening 192 are ordinarily in contact with each other. A jaw slot 202 is formed between the inside surface of the cylindrical walls 196 and the smaller diameter cylindrical walls of the conduit opening 192.

Mounting holes 198 through the seal ring 190 align with the plate mounting holes 178 and 172. Referring to Figure 21, the back plate 174 fits within a back plate recess 194 in the seal ring 190. Screw fasteners extend through the mounting holes 198,178, and 172, holding the front plate 166, the seal ring 190, and the back plate 174 together.

[00107] Referring to Figs. 20,21 and 22, a clamp rod 156 extending through the handle 152 is joined to a rod arm 212 having a rod arm pin 214 extending through the rod slot 176 in the back plate 174. At the top end of the tool 150, a clamp knob 154 is attached to the upper end of the clamp rod 156. The clamp knob and rod are rotatable relative to the handle 152, on a knob plate 158. Referring to Figure 22, wherein the seal ring 190 is removed for purpose of illustration, left and right side jaws 220 are pivotably attached on jaw pivot pins 224 on the back plate 174. A jaw link 222 connects the upper end of each jaw 220 to the rod arm pin 214.

[00108] In use, the tool 150 is placed into a pipeline 30 through an access fitting 40, as shown in Figure 31. The clamp knob 154 is positioned or turned so that the clamp rod 156 is pulled up. The jaws 220 and jaw links 222 are open, as shown in Figure 30. The seal lips 200 of the seal ring 190 are pulled apart, allowing the conduit opening 192 to fit over the conduit 32, as shown in Figure 30. The resilient seal ring 190 is deformed, as shown in Figure 30. With the pipe plug assembly 164 in the open position, spaces are present between the pipe plug assembly 164 and the inside walls of the pipeline 30. Accordingly, with the tool 150 in the position shown in Figure 30, flow continues past the pipe plug assembly 164. The tool 150 is maneuvered using the handle 152 and the thrust bar 162, to position the pipe plug assembly 164 into the pipeline 30, as shown in Figure 31, with the jaws 220 in the open position shown in

Figure 30. The deformed shape of the seal ring 190 allows the pipe plug assembly 164 to be more easily installed into position, as clearance spaces are provided between the deformed (non-round) edges of the seal ring 90 and the pipeline inner walls.

[00109] Once the plug assembly 164 is in place, the clamp knob 154 is turned to drive the rod arm 212 down. As the rod arm 212 moves down, the rod arm pin 214 causes the lower ends of the jaw links 222 and the upper ends of the jaws 220 to move apart. As a result, the jaws 220 pivot about the pivot pins 224. The lower pointed ends 226 of the jaws 220 drive the seal lips 200 together, and clamp the conduit opening 192 of the seal ring 190 around the conduit 32. As this occurs, the seal ring 190 moves from the deformed position shown in Figure 30 to the circular position shown in Figure 33.

The tapered cylindrical outer wall 196 of the seal ring 190 then seals against the inner walls of the pipeline 30. The upstream side of the wall 196 has a diameter slightly more than the downstream side. Flow through the pipeline 30 is stopped, without damaging the table 32.

[00110] The tool 150 is installed within a pressure housing or fitting attached to the access fitting 40, to prevent gas leakage from the pipeline 30, as is well known in pipeline technology. The tool 150 is removed by turning the clamp knob 154 in the reverse direction, thereby returning the jaws 220 back to the position shown in Figure 21. The tool 150 can then be pulled up and out of the pipeline 30.

[00111] Turning to Figs. 34,35, 36 and 37, an alternative pipeline stopper tool 240 has a pipe plug assembly 250, including folding components. As shown in Figs. 34 and 36, a center handle plate 258 is attached to a tubular handle 252. First and second side plates 260 and 264 are attached to opposite sides of the center handle plate 258 via

first and second hinge joints 262 and 266. First and second links 268 and 270 are pivotably attached to the first and second side plates 260 and 264, respectively, and to a first or inner and a second or outer tube 254 and 256 concentrically positioned within the handle 252. A resilient seal ring 272 is positioned over the center handle plate 258 as well as the first and second side plates 260 and 264. A conduit recess 274 extends through the seal ring 272 at a bottom center position.

[00112] As shown in Figure 37, a thrust bar 280 is attached to the handle 252.

Inner and outer tube handles 282 and 284 are attached respectively to the inner and outer tubes 254 and 256. Pivoting movement of the inner tube 254 via the inner tube handle 282 causes the second side plate 264 to pivot relative to the center handle plate 258.

Correspondingly, pivoting movement of the second or outer tube 256 via the outer tube handle 284 causes the first side plate 260 to pivot relative to the center handle plate 258.

[00113] In use, the tool 240 is installed into a pipeline 30 through a pressure housing and an access fitting 40. The first and second side plates 260 and 264 are in the folded or pivoted position shown in Figure 34. This allows the plug assembly 250 to be more easily positioned within the pipeline 30. The cable recess 274 fits over and around the cable 32. The inner and outer tube handles 282 and 284 are then pivoted in opposite directions. Referring to Figs. 34 and 35, as the inner tube 254 moves clockwise and the outer tube 256 moves counterclockwise, the side plates 260 and 264 are moved from the folded position shown in Figure 34, to the extended and flat position shown in Figure 26. This causes the circular outside edge 275 of the seal ring 272 to seal against the inside walls of the pipeline 30. In addition, the inside surfaces of the cable recess come into contact with and seal against the cable. With the side plates extended, as shown in

Figs. 35 and 36, flow through the pipeline 30 is stopped. As the seal ring 272 is resilient, it can flex and fold as the side plates pivot.

[00114] The tube handles 282 and 284 may be moved sequentially or simultaneously. The tube handles 282 and 284 may be replaced by a single handle and mechanism for simultaneously driving both tubes 254 and 256, with a single hand movement. The tool 240 is removed by reversing the direction of the tube handles 282 and 284, and then pulling the plug assembly 250 back out of the pipeline 30 by manipulating the thrust bar 280 and the handle 252.

[00115] The tools shown in Figures 20-37 are preferably provided as modifications of existing stopping tools. This approach has the benefit of gas industry acceptance and familiarity with the tools and procedures employed. These known tools may be provided with a modified plugging mechanism that provides a seal around the cable or conduit. If deploying the plug fitting around the cable in the pipe becomes difficult, the plug can be fitted on to a pressure housing with a clear viewing port that allows the operator to view the position of the cable conduit, as described in PCT/US/01/31468.

[00116] Another stopping or plugging tool 300, as shown in Figs. 38-42, has a stopper assembly 302 which seals against a cable and pipeline by deformation of a plug 304. The plug 304 is made of a resilient or deformable material, such as rubber. As shown in Figure 38, lips 306 on the plug 304 extend down around a cable recess 308. A <BR> <BR> rigid (e. g. , metal) drive plate 310 is positioned within the plug 304, at the bottom of a plunger recess 314, and above the conduit recess 308. The plunger recess 314 has an

upper or first section 328 having cylindrical sidewalls, and a conical section 330 joining into the cylindrical section 328.

[00117] A plunger 316, preferably made of a rigid material, such as metal, preferably has a flat bottom end 326 joining into a curved or hemispherical section 324, and a cylindrical upper section 322. When the plunger 316 is installed into the stopper assembly 302, the cylindrical section 322 of the plunger 316 fits within the cylindrical walls 328 of the plunger recess 314. As shown in Figure 38, the flat bottom end 326 of the plunger 316 is spaced apart from the drive plate 310. The plug 304 is in its deformed condition. As shown in Figure 38, all sections of the plug fit within the diameter DD.

[00118] Referring to Figure 40, in use, the stopper assembly 302 is attached to a plunger drive rod 318. The plunger drive rod 318 is driven up and down into the pipeline 30 by a driver 320. Various types of drivers 320 may be used. The plug tool 300, including the stopper assembly 302, the drive rod 318 and the driver 320 are installed on or in a pressure tight access fitting 40 on the pipeline 30. The stopper assembly is lowered into the pipeline. The cable recess 308 moves down on top of the cable 32, as shown in Figure 38. In this position, flow continues around the sides of the stopper assembly 302, due to the gaps G between the plug 304 and the inside walls of the pipeline 30. Flow continues as well alongside of the cable 32.

[00119] The driver 320 is then actuated forcing the stopper assembly 302 down into the pipeline 30. As this occurs, the plunger 316 moves down within the plug 304, until the plunger comes into contact with the drive plate 310. The plug 304 deforms and changes shape, as shown in Figure 39. The sides of the plug 304 bulge outwardly and

close up the gaps G. Simultaneously, the lips 306 of the plug 304 deform inwardly and close up around the cable 32. As shown in Figure 39, the pipeline 30 is then entirely plugged, stopping flow through the pipeline. The tool 300 is removed, to allow flow to resume, by reversing the driver 320 causing the plunger 316 to withdraw to the position shown in Figure 38. The elastic characteristics of the material of the plug 304 cause the plug to return to its original shape, as shown in Figure 38. The tool 300 can then be pulled up and out of the pipeline 30.

[00120] In the tools described above, the cable or conduit opening or recess 192, 274 or 308 is dimensioned to fit over or around the cable in the pipeline. Accordingly, a family or kit of pipe plug or stopper assemblies 164,240 or 302 may be provided, with each stopper assembly having a different size cable recess. Similarly, since different size plug or stopper assemblies are required for different size pipelines, a family or kit of tools having stopper or plug assemblies of different size may be provided.

[00121] The tool shown in Figures 38-42 is preferably used with conventional top half fitting supporting equipment. This approach has the benefit of gas industry acceptance and familiarity with the tools and procedures employed. The use of a modified plugging mechanism provides a seal around the cable or conduit.

[00122] In general, the tools shown in Figs. 20-49 use commercially available equipment to temporarily access the pipe and seal the access when finished. The tools generally can be used without the operator seeing the location of the conduit or cable. If the tool operator desires to view the conduit position, a viewing port in a housing through which the tool is positioned can be used.

[00123] Figures 43-49 show sealing or plugging of a pipeline containing a cable, using an inflatable airbag and a crescent strip. As shown in Figures 48 and 49, the crescent strip 350 has lips 354 contacting each other below a split cable recess 352. The strip 350 is preferably made of rubber or another flexible material. The outside wall or surface 355 of the strip 350 has a radius selected to match the inside radius R of the pipeline. The inside wall or surface 357 of the strip 350 has a radius T greater than the outside wall radius R.

[00124] In use, the crescent strip 350 is installed into the pipeline through a pressure fitting 41 attached around an access opening 42 cut into the pipeline. The crescent strip is lowered into the pipeline on an installation tool 348, which holds the strip in a partially folded position, as shown in Figure 44. In this position, the lips 354 are pulled apart and the split cable recess 352 is open. The cable recess 352 is lowered onto and around the cable 32. The crescent strip 350 is then released from the installation tool 348 and comes to rest as shown in Figure 45. The lips 354 close up around and seal to the cable.

[00125] Referring now to Figures 45 and 47, an airbag 360 is installed into the pipeline above the crescent strip. The airbag 360 is inflated. The crescent strip 350 provides a uniform smoothly curved surface for the inflated airbag to seal against. The inflated airbag pushes out against the inside pipeline walls, and against the crescent strip, thereby closing off the pipeline. To resume flow, the airbag is deflated and removed. The crescent strip is then remove via the tool 348.