SYSTEM FOR MAINTAINING CONDUITS AND PIPES IN A PIPELINE SYSTEM

Abstract

A system for maintaining conduits and pipes after their installation into a pipeline system used to transport material in a fluid or flowable form. The system includes a maintenance tool adopted for use inside the pipe, an umbilical attached to the maintenance tool for pulling the tool through the pipe; and a pluralities of bearings positioned around the umbilical in order to allow the tool to be pulled through the pipe around bends and turns in the pipe.

Claims

1. A system for maintaining pipes, said system comprising: a maintenance tool adopted for use inside a pipe; an umbilical attached to said maintenance tool for pulling said maintenance tool through said pipe; and a pluralities of bearings positioned around said umbilical, said bearings be adopted to allow said maintenance tool to be pulled through said pipe around bends and turns in said pipe.

2. The system of claim 1, wherein said plurality of bearings are attached to said umbilical.

3. The system of claim 1, wherein said plurality of bearings are formed of rollers.

4. The system of claim 1, further comprising a control unit for controlling the operation of said maintenance tool.

5. The system of claim 4, wherein said control unit comprises a central processing unit operating control software for controlling the operation of said maintenance tool.

6. The system of claim 4, wherein said control unit is adapted for remotely controlling said is maintenance tool.

Description

BRIEF DESCRIPTION OF THE DRAWING

[0032] The novel features of the present invention are set out with particularity in the following detailed description of the preferred embodiment. However, the invention will be understood more fully and clearly from the detailed description of the invention as set forth in the accompanying drawings in which:

[0033] FIG. 1-3 illustrate burial of a typical pipe line system;

[0034] FIG. 4 illustrates a prior art approach to cleaning and maintaining prior art pipeline systems;

[0035] FIGS. 5-11 illustrate various embodiments of the present inventions; and

[0036] FIG. 12 is a block diagram of a controller which may be used to control the device of the present invention.

[0037] FIG. 13 depicts a formula which can used to determine the position of a spin disk position as it is traverse through a 90 degree elbow;

[0038] FIG. 14 illustrates a three axis gyro used in accordance with the present invention;

[0039] FIGS. 15 and 16 illustrates liner material exiting a spray gun in accordance with the present invention;

[0040] FIGS. 17 and 18 illustrate the effects of a cathodic protection system; and

[0041] FIGS. 19 and 20 illustrate ways of electrically interconnecting isolated pipes during a lining operation in accordance with the present invention.

DESCRIPTION OF A PREFERRED EMBODIMENT OF THE INVENTION

[0042] A preferred embodiment of the present invention will be described with reference to FIG. 5-13.

[0043] The present invention provides a pipeline cleaning and maintenance device that is capable of routinely navigating and processing complex pipe geometries. The device of the present invention solves the problem of umbilical supply lines 51 and winch cable lock-up or seizing as they are drawn tight around bends in a pipeline system 52 as illustrated in FIG. 5. Friction resulting from this phenomenon is known by those experienced in pipe rehabilitation to be sufficient to break heavy winch cables or cause damage to the umbilical lines and pipe walls.

[0044] While sheaves or pulleys can be installed in large pipes to permit frictionless cable operation where man entry is permitted, use of such devices are time consuming to erect and impossible to deploy in small diameter pipelines.

[0045] FIG. 6 illustrates a cable carrier assembly in accordance with the present invention that is designed to negate friction and seizure of winch cables or umbilical supply lines attached to the tooling.

[0046] As can be seen in FIG. 6, a plurality of rollers 61 are connected to the umbilical 62 and arranged as shown to eliminate binding and minimize friction throughout the length of any cable runs.

[0047] The chain or wire rope sheath can be used to winch the system in the event of power loss. Also, the rolling elements 62 permit longer tether deployments than could be made with unsupported hoses and cables.

[0048] This system of the invention allows multiple 90 degree turns to be easily traversed and can be rolled onto a take-up reel as tools are retracted from the piping system.

[0049] In testing of the present invention, it was noted that as the spin cast disk, a spinning metal disk used to disperse lining material around the inner circumference of the pipe wall, was driven into and through 90 degree elbow fittings that disk orientation (ideally operated centerline in the pipe), caused inconsistencies in the amount of material deposited onto various areas of the internal pipe wall.

[0050] This phenomenon was prevalent as the tool entered and exited a fitting, as well as passing throughout the fittings radius. In a 90 degree fitting, there is simply far more surface area to be covered on the outer extremities of the inner pipe wall. As illustrated in FIG. 7, it was discovered that by providing the proper angular, as well as linear stand-off distance of the spin-cast disk to the pipe wall, that even dispersal of lining materials could be achieved. Coating thicknesses to within 10 thousands (0.010″) deviances were found to be reproducible using this technique.

[0051] This mechanism becomes very important as many liner materials cannot be applied too thick as excessive heat can build up in the coating and cause exothermic reaction, resulting in a loss of bond to the pipe wall or cracking and bubbling to occur which simply compromises the lining system.

[0052] The device of the present invention can be used with many different lateral pipe sizes, includes sizes of 24, 30, and 36 inches.

[0053] FIGS. 8-11 illustrated a 24 inch device with pipeline mock-up for cleaning, lining and inspection of pipelines.

[0054] The device of the present invention is controlled and driven by a computerized controller using appropriate software. The controller controls the device for optimal speed and position.

[0055] FIG. 13 is a block diagram that illustrates the basic components of a controller 1 which can be used to control the device of the present invention.

[0056] Controller 1 includes a CPU 2. The CPU is used for executing computer software instructions as is known in the art. CPU 2 is coupled to a number of other elements via a signal and data bus 3 as is also known in the art. These elements include ROM 5 (Read Only Memory) which may be used to store computer software instructions, RAM 6 (Random Access Memory) which also may be used to store computer software instructions, I/O Interface 7 which may be used to interface CPU 2 to elements and/or functions that are external to controller 1, and Non Volatile Memory 4 which may be used to store computer software instructions as well.

[0057] As mention above, I/O Interface 7 is used to interface CPU 2 to elements or functions that are external to controller 1. These external elements might include Keyboard 11, Visual Display 12, Speaker 13, and USB Port 14.

[0058] Depending on the tasks to be performed by controller 1, its computer software instructions might be divided into two or more separate and distinct categories which are stored in separate portions of ROM 5, RAM 6 and/or Non Volatile Memory 4. In some devices, a basis set of low level operating instructions, known in the art as firmware 9, might be stored in, for example, ROM 5. These low level rudimentary instructions provide the necessary instructions for how the controller communicates with the other computer hardware. Such instructions are necessary for the controller to perform any useful work, regardless of the application for which the device is to be used.

[0059] The computer instruction set that is executed by CPU 2 to perform the particular tasks required of the controller is often call “application software” and operationally “sits” on top of firmware 9. As illustrated in FIG. 1, application software 10 is stored in RAM 6. Application software 10 could also be stored in ROM 5 or in Non Volatile Memory 4.

[0060] Firmware 9 allows application software 10 to efficiently interface with the other device hardware, such as the elements that are coupled to CPU 2 via I/O Interface 3.

[0061] Again, depending on the tasks to be performed by controller 1, a third set of software instructions known in the art as an operating system 8 might operationally “sit” between firmware 9 and application software 10. Operating system 8 is shown as being stored in Non Volatile Memory 4 in FIG. 1 but could be store in RAM 6 as well.

[0062] Operating system 8 is the software that is responsible for the management and coordination of activities and the sharing of resources within controller 1.

[0063] Further embodiments of the present invention will now be described.

Liner Application Using a Spin-Disk & Spray Nozzle Configuration

[0064] A control method & apparatus for coating an internal pipe wall with a polymer lining material providing a uniform and reproducible thicknesses to be achieved throughout the conduit thus yielding consistent physical material properties throughout including radii.

[0065] Spray application nozzles use pneumatics to force liquid under pressure through a very small diameter orifice, creating unstable sheets of liquid that break up into a defined range of droplet sizes. Due to the patterns formed by each nozzle, it is difficult to arrange them to get even coverage. Therefore it is impossible to suggest or ensure that optimal material properties thus liner performance will result from field installations.

[0066] Thus, in this method, a spray nozzle is used to apply the liner material to the surface of a rotating disk. The pneumatically actuated nozzle provides the ability turn on- and off the material flow as well as thoroughly mix the dual component poly material prior to casting. The rotating casting disk is used to further blend the lining material. Centrifugal force applied to the disk causes the lining material to be evenly dispersed from the perimeter of the spinning disk in a continuous 360 deg. pattern on the adjacent pipe wall.

[0067] This casting method is preferable for evenly and reliably coating the inside surface of the pipe wall. However, as this assembly is propelled around fittings with radii an uneven distribution of material will result. The effects of this phenomena, (uneven application & thickness), can be minimized or corrected by positioning the spinning disk in the appropriate position inside the conduit. This will permit deposition of the liner material to be concentrated or minimized where desired promoting even distribution throughout the radii.

[0068] FIG. 13, depicts a formula which can be used to determine the necessary position of the spin disk position as it is traversed through a 90° elbow.

Sensors/Control Loop

[0069] Using commercially available digital accelerometers and gyro's attached to the centralizer platform the pitch, yaw, and roll of the centralizer tool may be determined throughout the lining process.

[0070] A three axis gyro, FIG. 14, provides the necessary data required to resolve the optimal position, using the above formula, of the spin disk.

[0071] The spin disk, currently powered by an air motor, is attached to a multi-axis positioning mechanism. This positioning mechanism may be derived from rotational and single axis sweep mechanism, a motor driven x-y positioning stage, or combination of all depending on available space for the assembly which is primarily influenced by pipe “ID”. I assume we will further expand on the advantages of each approach prior to actual filing should that be necessary.

[0072] Assuming space is sufficient to incorporate a controllable nozzle axis, positioned inline with the roll axis, X in FIG. b, additional capabilities for manipulating deposition of liner materials may be exploited. Under normal circumstances, the liner material exiting the spray gun is directed to impact the spin disk as closely to the spindle mounting shaft as possible, FIG. 15.

[0073] Disk rotational speed, in conjunction with surface area of the spin disk face are optimized to effect and even distribution of the liner material to exit the disk in an a 360° manner.

[0074] Adjusting the contact point of the liner material on the surface of the spin disk toward the outer edge of the disk will accelerate material dispersal from the outer edge of the spin disk, FIG. 16.

[0075] As the contact distance is manipulated volume and trajectory of the liner material can be altered in conjunction with the spindle RPM to determine location and resulting material accumulation on the adjacent pipe wall.

[0076] This element of control will prove especially useful when constructing systems for lining small pipe using a rotary+sweep axis combination as discussed above. The aforementioned variables and calculations also derive the maximum possible disk diameter which can be utilized inside a particular size pipe. Where required parabola shapes as depicted in the above illustrations may be substituted with cone shaped spin disk designed to provide sufficient surface area required to evenly disperse lining materials.

Construing Conductively Interconnected Pipe Sections

[0077] A method and apparatus for electrically connecting metallic pipe sections which are electrically isolated at each joint section by rubber or fiber seals during the spray-in liner installation.

[0078] Corrosion requires three components to simultaneously exist and react in a metallic piping system. An anode, cathode, and electrolyte must be present for corrosion to occur. Removal of any one of these abovementioned components from the equation is sufficient to disrupt the potential for corrosion. For instance lining a cast iron pipe in a municipal water system restricts oxygenated water (the electrolyte) from contacting the metallic pipe wall eliminating internal corrosion, pitting and ultimate failure. However, it is common for aggressive soil conditions to result in pipe wall failure do to “external” pipe wall corrosion. Therefore, measures beyond internal lining must be employed to provide protection of internal and external surfaces in electrically isolated piping systems.

[0079] Cathodic protection is a popular method of protecting metallic piping systems from corrosion. It is common practice to direct extraneous electrical currents known to induce anodic and cathodic interaction to replaceable sacrificial materials via cables or wires attached to a piping system, FIG. 17. Steel pipe, and other large transmission lines are often protected in this fashion. In the event pipe sections are electrically isolated, each isolated pipe section must be independently connected or joined into a common circuit attached to the sacrificial anodic materials, FIG. 18. This practice is generally considered cost prohibitive because of the frequency of required excavation or impossible do to disruption in urban areas. Therefore, this technique is valuable where piping assets have been buried and are electrically isolated, such as potable water lines or natural gas distribution lines. This rehabilitation procedure not only eliminates the requirement for multiple excavations but permits both internal and external protection of the pipe to be achieved in a single cost effective procedure which could extend the life of the piping system indefinitely.

[0080] Interconnection of electrically isolated pipes during the lining process can be accomplished in two ways:

[0081] 1. Conductive material(s) such as carbon nanos, conductive graphene, carbon black, or other applicable “conductive materials” can be doped or blended into the lining formulation, or injected at the point of dispersion onto the pipe wall in sufficient measure as to result in a continuous conductive coating which will permit current flow to a singular connection point and attached to sacrificial anode materials.

[0082] 2. A single “dense” conductor strand, (wire, tape, foam, paste etc.), applied through an applicable dispensing mechanism installed on the lining centralizer can be utilized to interconnect isolated pipe sections as the spray-in process occurs. The conductor will be encapsulated and held in place permanently by the lining system which is bonded to the pipe wall. One such example, FIG. 19, represents a series of metallic wire conductors boded to a single adhesive tape. Note: Dissimilar “foil” materials such as copper or aluminum, FIG. 20 should not be used on an iron pipe wall as these materials would likely be consumed via the above described cathodic action. Conductor wires should be iron based and adhesive tape should be comprised of an inert fabric or other material. Also, the adhesive material should be formulated as to not react aggressively with the liner materials being sprayed.

[0083] While the foregoing specification teaches the principles of the present invention, with examples provided for the purpose of illustration, it will be appreciated by one skilled in the art from reading this disclosure that various changes in form and detail can be made without departing from the true scope of the invention.