WO2006063099A2

WO2006063099A2 - Voc and hrvoc repair method

Info

Publication number: WO2006063099A2
Application number: PCT/US2005/044353
Authority: WO
Inventors: Alfonso J. Guerrero; Alfonso N. Guerrero
Original assignee: Guerrero Alfonso J; Guerrero Alfonso N
Priority date: 2004-12-07
Filing date: 2005-12-06
Publication date: 2006-06-15
Also published as: WO2006063099A3

Abstract

A method for repairing VOC and HRVOC leaks in piping or other components and an apparatus in support thereof comprising a retaining member surrounding a joint with means to compress the backing material used to effect the repair. The method involves the placement of a packing material in proximity to the area of the leak, placing a backing material substantially in contact with the backing material, and then retaining the backing material in place to compress the packing material.

Description

VOC AND HRVOC REPAIR METHOD

BACKGROUND OF THE INVENTION The present invention relates generally to the field of pipe repair and more specifically, the present invention relates to a method that aids in stopping and preventing further leaks of gases or liquids, particularly volatile organic carbons (VOCs) and highly reactive VOCs (HRVOCs), from damaged or punctured containers, such as piping.

Reducing and eliminating emissions of fluids such as steam, VOCs₅ and HRVOCs from containers such as a pressurized pipe in existing construction can be problematic. For instance, leakage of VOCs and HRVOCs presents safety and health hazards. The inability to contain and stop such leaks may require reporting to regulating agencies and/or refitting of the piping. Refitting requires the operator to take the unit offline for expensive repairs, plus the loss of revenue from non-production.

The generally accepted method of box covers for flanges and fittings, known as the packing injection method, involves surrounding the leaking joint or other component with a metal box into which is injected a substance that hardens to block the flow from the leak. But this method has a high failure rate and is not dependable over time. Additional, more drastic, methods for plugging a leak include drilling and then attempting to plug the leak. But such methods are often time consuming and destructive of the pipe and/or fittings, thus shortening their useful life requiring more frequent refitting. It is therefore apparent that there is a need for an improved method of quickly repairing such leaks in place without resort to inconsistent methods or destructive means or refitting, and it is one of the objects of the present invention to provide such an improved method.

Although the present application will make repeated reference to the repair of leaks in pipes, the method of the present invention is not limited to that application. The method is also utilized for the repair of process components such as valve packings, screw connectors, flanges, and compressors. Similarly, although the method of the present invention is described herein as being intended for repairing leaks of fluids, the method has particular application for the repair of leaks in process components utilizing volatile organic carbon (VOCs) and heating and refrigeration (H.R.) VOCs such as methane, propane, ethylene, propylene, gas, alcohol, and the like.

Another object of the present invention is to provide a method, and an apparatus for implementing that method, for quickly repairing VOC and HRVOC leaks without destructive intervention, disassembly or refitting and thereby avoiding or reducing downtime of the unit, component, and/or production facility.

With the present disclosure, it is now possible to repair leaks in pipes and other components in position with confidence. In addition, once the repair is made, it provides a substantial benefit by maintaining the integrity of the repair on piping apparatus that sustains significant vibration, such as valves that open and close on repetitive cycles.

There is, therefore, a need for an improved method to repair leaking or ruptured piping and other components, and it is a further object of the present invention to provide a method that meets this need.

Other objects, and the advantages, of the present invention will be made clear to those skilled in the art by the following description of the presently preferred embodiments thereof.

SUMMARY OF THE INVENTION

These objects are met in a first aspect of the present invention by providing a method of repairing VOC and HRVOC leaks in place comprising the steps of depressurizing the leaking pipe or other component, cleaning the area around the leak, applying a packing material such as an epoxy adhesive compound to the leak area, and retaining the packing material in place by compression or by applying a backing. The packing material may be put in place by hand or with the aid of an applicator such as a screwdriver, putty knife, or other suitable implement, and then wrapped with a flexible tape as a backing. A further example is use of a water-activated compression wrap alone or in addition to tape backing. The heat characteristics of the pipe may suggest the type of backing to be used.

In a second aspect, the present invention provides a method of VOC and HRVOC repair comprising the method of application of a packing material as described in the present invention further comprising a retainer for providing additional support for retaining the packing material. The retainer comprises a support member surrounding the pipe and packing material and a means for reducing the diameter of the support member so as to compress the packing material and to retain the packing material in place, for instance, for the repair of a pipe or other component that is subjected to vibration or other physical stimulus. An example of such a repair is the repair of a pipe joint between two flanges after the epoxy is put in place, the joint is then wrapped with TEFLON® rope as a mechanical backing, which is then surrounded by a water activated wrap to apply compression as it cures, hi a further example of a pipe repair requiring more substantial backing after the TEFLON® rope is put in place, a metal or other high tensile material band clamp is wrapped around the pipe covering the TEFLON rope and fastened in place.

BRIEF DESCRIPTION OF THE DRAWINGS

Figure 1 is a perspective view of a preferred embodiment of the band clamp apparatus in relation to the pipe flanges;

Figure 2 is a longitudinal view of the preferred embodiment of the installation of the band clamp apparatus in accord with the teachings of the present invention;

Figure 3 is a sectional view, taken along the line B-B, of Fig. 2 of the preferred embodiment.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT Both the method and the apparatus described herein are designed to repair VOC and/or HRVOC leaks to piping or other components. Those skilled in the art will recognize, however, that it may be necessary to make certain changes in the preferred embodiments described herein in accordance with the field conditions encountered.

Referring to Fig. 1, there is shown a drawing of the preferred method of repairing a leak between pipe flanges in accordance with the teachings of the present invention. The invention particularly relates to a clamping apparatus 10 for retaining a packing material such as an epoxy adhesive 23. A typical pipe joint 11 upon which the method of the present invention is employed is comprised of terminal pipe ends 12 integrally attached to flanges 13 with said flanges 13 having substantially planar flange faces 14 opposed and separated by a gasket 15, said flanges 13 held in substantial alignment by a reversible connecting means such as threaded studs 16 and retaining nuts 17. The retaining apparatus 10 of the preferred embodiment is comprised of a generally flat support member 18 having a first end 19 and a second end 20, further comprising a generally U-shaped channel 21 around the circumference and attachment means 22 to engage the first end 19 and second end 20 of the support member 18, thereby adjusting the attachment means 22 to direct said ends 19 and 20 to a closer proximity. For instance, apparatus 10 may be made out a variety of materials comprising metals, plastics, or other substances having sufficient strength or chemical integrity for the particular application. In use, as shown in FIGS. 1, 2, and 3, apparatus 10 is placed around the joint in contact with the exterior flange edge 14a to provide support for the packing material.

The first step of the repair method of the preferred embodiment comprises placement of the packing material between the flange faces 14. The epoxy packing material 23 may be put in place in proximity to the location of the leak by hand or with the aid of an applicator to place the epoxy such as a screwdriver, putty knife, or other suitable implement. Although those skilled in the art will recognize that other epoxies may be suitable for use in this application depending upon such factors as, for instance, the fluid passing through the pipe joint 11, chemical reactivity with the fluid passing through the pipe joint 11, the temperature of the fluid passing through pipe joint 11, ambient conditions, and whether pipe joint 11 is subject to vibration (for instance, by close proximity to a motor, compressor, or valve that opens or closes), in the preferred embodiment, the epoxy 23 that is utilized in the method of the present invention is a two- part epoxy that is cured in place between the flange faces 14. In a particularly preferred embodiment the epoxy 23 is a so-called "Two-in-One" epoxy putty stick available, for instance, from Pipe Wrap Co. (Houston, TX). Epoxy 23 is restrained in place between the flange faces 14 by a flexible backing

24. In one embodiment, the flexible backing 24 is a TEFLON® rope, where TEFLON® has high resistance to VOC chemical degradation and in cross section resists substantial compression, thereby aiding in transmitting any retaining or compressive forces from the retaining apparatus 10 inward toward the epoxy, and aids in resisting expansive forces of the VOC transmitted against and through epoxy patch 23. Those skilled in the art will recognize that TEFLON® rope is available commercially in a range of diameters, and that the particular diameter utilized depends on the application and such factors as the size of the leak and the space between flange faces 14; in short, the diameter of the rope depends upon the size of the void that must be filled with the TEFLON® rope. Successful repairs have been made where the void to be filled was as large as an inch by packing two half- inch diameter TEFLON® ropes into the void side-by-side.

Those skilled in the art will recognize from this disclosure that the present invention is not limited to the use of epoxy or TEFLON® rope and that, depending upon the above-described conditions, the packing material that is utilized in a particular repair effected in accordance with the method of the present invention and the backing 24 may be comprised of any variety of materials appropriate for the repair conditions, including, for example, any of the several packing materials available from The Flexitallic Group (www.flexitallic.com); graphite packing rope such as is available under the brand name GARLOCK, as well as many other packing and gasket materials marketed under the GARLOCK, MILL-WRIGHT, GRAPH-LOCK, and SYNTHEPAK brand names (Garlock Sealing Technologies, Palmyra, NY); materials such as those marketed under the SEQUEL® brand name, as well as GFO fiber packings (W.L. Gore & Associates, www.gore.com); mechanical packings and materials such as those marketed under the JM CLIPPER brand name (www.sealingdevices.com); expanded PTFE/Graphite (XPG) yarns; carbon/graphite filament packings; ARAMID; DURLON; fiberglass; PBI® (Celanese Corp. (www.celanese.com)); materials such as those available from SLADE and so-called Seal Foil compression packing (Tampa Rubber & Gasket Co., Inc., Tampa FL); graphite; flax; PTFE; basalt; SBR; non-asbestos/CAF; ceramic; mica; rubber strip and/or sheet; silicone sheet, strip, and sponge extrusions; polyurethane shapes, molded, strips, sheets, and/or belt and/or extrusions; TEFLON®, KEVLAR®, NOMEX®, TEFLON® glass belts, TEFLON® glass tape, and/or a suitable synthetic rubber such as NEOPRENE® and EPDM, vinyl PVC, VITON®, butadiene, and/or polybutadiene polymers. In the case of a synthetic rubber or other polymer, it may be useful to utilize a material that is extruded or formed in the form of a tube or other similar hollow or otherwise compressible configuration. Those skilled in the art who have the benefit of this disclosure will also recognize that certain metal-jacketed gasket materials may also be used to advantage in connection with the method of the present invention, including, for instance, those filled with asbestos, CAF₅ PTFE, and GRAFOIL (Advanced Energy Technology, Lakewood, OH), that are comprised of soft iron, all grades of steel, brass, MONEL, INCONEL₅ aluminum, brass, cooper, titanium, nickel, and INCOLOY (Huntington Alloys, Huntington, WV).

In an alternative embodiment, a retainer 25 substantially encircles the joint 11. Retainer 25 may comprise the rope backing 24 described above or, in other embodiments, retainer 25 takes the form of a wrap 24 or retaining apparatus 10 for enclosing the flange faces 14 having the epoxy applied thereto. A suitable wrap 24 is comprised of a material such as a water- or heat-activated fiberglass wrap, or other materials that are applied in place. Although some degree of contraction of such a material upon activation may be helpful to hold the epoxy patch 23 in place between flange faces 14, especially in applications in which the fluid passing through pipe joint 11 is pressurized, those skilled in the art will recognize that compression is not a required element of the method of the present invention. In the case of the use of a retaining apparatus 10, retaining apparatus is placed around the joint in contact with the exterior flange edge 14a in the manner described above and then tightened to restrain and/or compress the materials between flange faces 14 to complete the repair. Those skilled in the art who have the benefit of this disclosure will recognize that certain changes can be made to the method of the present invention without changing the manner in which those parts function to achieve their intended result, and any modifications which do not deviate from the scope of the invention are considered to be included therein. For instance, the support member channel 21 of the retaining apparatus 10 allows for location of the backing 24 and wrap 25 substantially directly over the epoxy 23. However, in another embodiment, no channel 21 is necessary and the supporting member 18 is substantially flat across its width. In short, the foregoing description of the preferred embodiments of the invention has been presented for purposes of illustration and description. It is not intended to be exhaustive or to limit the invention to the precise form disclosed, and any modifications and variations are possible in light of the above teaching without deviating from the spirit and scope of the invention. The embodiments described are best selected to explain the principles of the invention and its practical application to thereby enable others skilled in the art to best utilize the invention hi various embodiments and with various modifications as suited to the particular purpose contemplated. AU such changes, and others which will be clear to those skilled in the art from this description of the preferred embodiments of the invention, are intended to fall within the scope of the following, non-limiting claims.

Claims

WHAT IS CLAIMED IS:

1. A method for repairing a VOC or HRVOC leak in a pipe or other component comprising the steps of: applying an packing material to the exterior of a pipe or other component in proximity to the location of a VOC or HRVOC leak; applying a backing material substantially in contact with the packing material applied to the exterior of the pipe or other component; and retaining the backing material in place in contact with the packing material.

2. The method of claim 1 additionally comprising depressurizing the pipe or other component to substantially reduce or eliminate the pressure gradient of the leaking material.

3. A pipe or other component repaired in accordance with the method of claim 1.

4. An apparatus for use in the method of claim 1 comprising a retaining member comprising a first end and a second end with attachment means, said retaining member being placed substantially in contact with the backing material and held in place by said attachment means.