Pipe fittings having integrated thermoplastic with improved melt-flow characteristics for cured in place pipe systems and associated method of use

Abstract

A fitting including a tubular extension, flange with apertures, and interface there between is fused with surrounding cured in place pipe and subsequently connected with an adjoining fitting, to connect two segments of pipe in a pipeline. The tubular extension is sized and shaped to mate with the host pipe with which it is associated, and the flange is sized, shaped, and has an aperture pattern that corresponds with the fitting to which it will be attached.

Claims

1. An uncured fitting for use with a CIPP having needle punched tubular substrate including a plurality of integrated thermoplastic fibers, said tubular substrate constructed of multiple overlapping layers that aren't attached one to another, said uncured fitting comprised of a fitting substrate having a tubular extension joined with a flange at an interface, said fitting substrate constructed of plurality of carbon fibers, aramid fibers and thermoplastic fibers needle punched together, wherein said fitting substrate is curable upon the application of blown air at approximately 380-470° F., at a pressure of approximately 5-20 psi, for approximately 5 to 90 minutes, and wherein said tubular substrate and said fitting substrate are chemically and structurally bonded upon curing.

2. A pipe repair system including a CIPP chemically and structurally bonded with a fitting, said CIPP including: A. A needle punched tubular substrate including a plurality of integrated thermoplastic fibers, said tubular substrate constructed of multiple overlapping layers that aren't attached one to another; B. A bladder surrounding said tubular substrate; and C. A film surrounding said tubular substrate, and wherein said CIPP and said fitting are constructed of substantially identical materials.

3. A method of repairing a pipe including the steps of: A. Inserting an uncured CIPP into a pipe segment having a compromised portion, said CIPP including a needle punched tubular substrate including a plurality of integrated thermoplastic fibers, said tubular substrate constructed of multiple overlapping layers that aren't attached one to another; a bladder surrounding said tubular substrate; and a film surrounding said tubular substrate; B. Curing said CIPP; C. Positioning at least one fitting onto a distal end of said pipe segment; D. Curing said fitting by blowing air at approximately 380-470° F., at a pressure of approximately 5-20 psi, for approximately 5 to 90 minutes; and; E. Connecting said fitting to an adjacent corresponding fitting.

4. The method of claim 3 wherein said step of positioning at least one fitting onto a distal end of said pipe segment includes the step of positioning at least one fitting constructed of a substantially identical material as said CIPP.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) FIG. 1 depicts a known method of repairing a segment of pipe with:

(2) FIG. 1A showing a pipeline including a segment of pipe in need of repair;

(3) FIG. 1B showing removal of damaged segment;

(4) FIG. 1C showing attachment of conventional fittings to ends of CIPP repaired host pipe;

(5) FIG. 1D showing connection of conventional fittings to CIPP repaired host pipe and application of internal patch;

(6) FIG. 1E showing application of external patch; and

(7) FIG. 1F showing introduction of repaired host pipe to pipeline;

(8) FIG. 2 depicts another known method of repairing a segment of pipe with:

(9) FIG. 2A showing a pipeline including a segment of pipe in need of repair;

(10) FIG. 2B showing removal of damaged segment;

(11) FIG. 2C showing removal of conventional fittings from ends of CIPP repaired host pipe and internal band ready for insertion;

(12) FIG. 2D showing connection of conventional fittings to CIPP repaired host pipe and internal bands there within;

(13) FIG. 2E showing external bands poised for positioning; and

(14) FIG. 2F showing external bands in position; and

(15) FIG. 2G showing introduction of repaired host pipe to pipeline;

(16) FIG. 3 is a photograph of a fitting of the present invention;

(17) FIG. 4 is a photograph of 7 blind flanges of the present invention;

(18) FIG. 5 depicts the substrate used to construct fittings of the present invention;

(19) FIG. 6 depicts a method of repairing a segment of pipe according to the present invention with:

(20) FIG. 6A showing a pipeline including a segment of pipe in need of repair;

(21) FIG. 6B showing removal of conventional fittings but with segment not removed;

(22) FIG. 6C showing uncured CIPP within host pipe;

(23) FIG. 6D showing cured CIPP within host pipe;

(24) FIG. 6E showing fittings to be placed at each end of CIPP repaired host pipe; and

(25) FIG. 6F showing CIPP repaired host pipe with cured in place fittings;

(26) FIG. 7 depicts a fitting having a female tubular extension; and

(27) FIG. 8 depicts a fitting a male tubular extension.

DETAILED DESCRIPTION OF THE INVENTION

(28) The following detailed description is of the best currently contemplated modes of carrying out exemplary embodiments of the invention. The description is not to be taken in a limiting sense, but is made merely for the purpose of illustrating the general principles of the invention, since the scope of the invention is best defined by the appended claims.

(29) The following structure numbers shall apply to the following structures among the various FIGS.: 10—Fitting; 12—Tubular extension; 14—Flange; 16—Interface; 17—Apertures; 18—Proximal end; 19—Distal end; 20—Host pipe; 21—Bolts; 22—Pipeline; 23—Pipe segment; 24—Pipe junction; 25—Conventional fitting; 28—Compromised portion; 29—Repaired portion; 30—Cured In Place Pipe (CIPP); 31—Substrate; 32—Fibers; 34—Needle punch; 40—Heater; 42—Air; 60—Internal patch; 62—External patch; 64—Internal band; 66—External band; and 70—Blind flange.

(30) Broadly, the present invention pertains to a fitting that is cured in situ, thereby fusing with surrounding cured in place pipe. The fitting is subsequently connected with an adjoining fitting, to connect two segments of pipe in a pipeline.

(31) Fitting 10 of the present invention is depicted in FIG. 3, and generally includes tubular extension 12, flange 14 which defines a plurality of apertures 17, and interface 16 connecting tubular extension to flange. Tubular extension 12 is sized and shaped to mate with host pipe with which it is associated. Likewise, flange 17 is sized, shaped, and has an aperture pattern that corresponds with the fitting to which it will be attached. The fitting to which fitting 10 will be attached may be a conventional fitting, or fitting of the present invention. The dimensions of flange 10 can vary widely, depending on the application, with the following approximate dimensions being preferred: height of 0 to 20 ft; outer diameter at proximal end of 3″ to 130″; outer diameter at distal end of 3″ to 120″; inner diameter at proximal end of 2.5″ to 110″; inner diameter at distal end of 2.5″ to 110″; thickness of walls 0.125″ to 10″; diameter of flange 5″ to 150″; number of apertures 0 to 3; thickness of flange 0.125″ to 6″; angle of transition between tubular portion and flange 0 to 180 degrees; and diameter of apertures 3″ to 120″.

(32) FIG. 4 is a photograph of seven blind flanges 70 according to the present invention. Blind flanges 70 are generally used in the industry as an “end cap” where a pipe's flow is cut off. The dimensions of blind flanges 70 can vary widely, depending on the application, but a diameter of approximately 3″ to 120″, and thickness of approximately 0.125″ to 10″ is generally preferred.

(33) Fittings 10 and blind flanges 70 of the present invention are preferably constructed of substrate 31. Referring to FIG. 5, substrate 31 includes a plurality of carbon, aramid and thermoplastic fibers 32 needle punched 34 together, with each fiber being preferably approximately 1″ to 4″ long, and approximately 0.31 mm to 1 mm thick. An example of a commercially available carbon fiber suitable for use is Tenax UMS40 from Toho Tenax of Rockwood, Tenn. The aramid fibers preferably have a length of approximately 1″ to 4″, and thickness of approximately 0.31 mm to 1 mm. An example of a commercially available aramid fiber suitable for use is KEVLAR K29 AP from DuPont of North America. The thermoplastic fibers preferably have a length of approximately 6 mm to 2500 mm, and thickness of approximately 0.31 mm to 1 mm. The thermoplastic of the present invention is preferably polypropylene, with an example of a commercially available polypropylene thermoplastic being Hyperform HPN-68L from Milliken of Spartanburg, S.C., USA having approximately 309 to 400 degree melt and cure points at a pressure of approximately 5 to 20 psi. It should be understood that thermosetting materials are not desired since the fittings and blind flanges are cured during manufacturing, and subsequently cured in situ during installation. Thus, as used herein, “cured” shall mean melting and hardening or rehardening.

(34) The proportion of carbon fibers in substrate 31 is approximately 10 to 60% by weight. The proportion of aramid fibers in substrate 31 is approximately 0 to 15% by weight. The preferred proportion of fibers in substrate 31 is approximately 40% carbon, 0% aramid, and 60% thermoplastic, by weight.

(35) Fibers are needle punched 34 together by conventional methods in a directional format. However, other combinations are also suitable. Substrate 31 can be produced in a variety of thicknesses, typically approximately 1.5 mm-9.0 mm, as appropriate for the specific application.

(36) The manufacturing of fittings/blind flanges from a substrate first requires that different sizes are created. Next, the substrate is compressed and heated sufficiently to take the shape of the mold. Finally, the substrate is cooled back to room temperature and then removed from the mold.

(37) FIG. 6 depicts some of the critical steps in using fittings 10 of the present invention. FIG. 6A depicts pipeline 22 including pipe segment 23 having compromised portion 28 in need of repair. FIG. 6B depicts excision of conventional fittings 25 from terminal ends of host pipe 20 with host pipe itself staying substantially in position. This is preferably achieved by removing bolts, cutting terminal ends of pipe, and removing terminal end of pipe with corresponding half of conventional fitting 25. This is a difference and improvement over conventional methods where the entire pipe segment is removed, as depicted in FIGS. 1B and 2B. Removing only terminal ends with fittings saves a lot of time and labor because the entire pipe segment doesn't need to be “dug out” of the ground. Digging out a pipe segment can be particularly problematic where multiple pipelines are present in one area, as is often the situation.

(38) As shown in FIG. 6C, excision of conventional fittings 25 provides access points through which uncured CIPP 30 can be fed into host pipe. As shown in FIG. 6D, CIPP 30 is cured using heater 40 which forces superheated air 42 at a specific pressure and for a specific duration. The result is host pipe 20 being internally lined with cured CIPP 30 thereby forming repaired portion 29. Although not shown, end of CIPP extending beyond host pipe are subsequently cut and removed.

(39) As shown in FIG. 6E, fittings 10 are positioned onto terminal ends of CIPP-enhanced host pipe 20. Although not shown, fittings 10 are subsequently cured. It should be understood that specific configurations will vary according to project variables, but that the method will generally follow identical steps, including that the outer surface of fitting extension 12 and inner surface of liner 20 are reheated in order to fuse together. This configuration would be reversed if using a female-type fitting in order to achieve the desired flow of fluid in the pipe.

(40) The finished product depicted in FIG. 6F is a CIPP-enhanced host pipe with cured in place fittings, bolted to fittings 25 or 10 of adjoining pipe segments 23. Preferably gaskets, not shown, are positioned between corresponding fittings 25, 10. The resulting CIPP and fitting are a substantially inseparable structure that is strong, flexible, and resilient to leakage and deterioration.

(41) Referring to FIGS. 7 and 8, it should be understood that tubular extension 12 can engage with host pipe 20 in a female or male configuration, respectively. As would be understood by those in the art, the selection of female versus male configurations would depend on the direction the fluids within the pipeline are flowing, among other factors.

(42) Specifications of certain structures and components of the present invention have been established in the process of developing and perfecting prototypes and working models. These specifications are set forth for purposes of describing an embodiment, and setting forth the best mode, but should not be construed as teaching the only possible embodiment. Rather, modifications may be made without departing from the spirit and scope of the invention as set forth in the following claims. It should be understood that all specifications, unless otherwise stated or contrary to common sense, are +/−10%, and that ranges of values set forth inherently include those values, as well as all increments between. Also it should be understood that “substantially” and the like should be construed to mean generally, but allowing for irregularities due to material or manufacturing differences, human variances, and so forth.