Field of the Invention

[0001] The present invention relates to a coupling for connecting tubular conduits, in particular for connecting lengths of pipe as part of a fluid transport system.

Background of the Invention

[0002] Fluid transport systems are known for conveying materials, such as liquids and gasses. The systems may include domestic plumbing systems installed in a building for conveying, for example, water or oil. These plumbing systems may include pipes for building heating systems, fire protection sprinkler systems and rising mains pipes and waste water pipes. The systems may also include oil and gas pipelines for conveying fuel over thousands of miles and pipe systems used in mining applications. The tubular conduits used in fluid transport of fuel may be made of different metals, including steel, iron, copper, aluminium and plastic.

[0003] For smaller diameter pipes, push fit couplings can be used, for example as described in GB 2,378,992. However, for pipe diameters above around 5cms, the force required to push the end of a pipe into such a push fit coupling becomes too high for manual connection. In addition, pipes connected by push fit couplings are able to rotate relative to each other, which can cause valve taps to move out of an optimum position.

[0004] For larger diameter pipes, welded joints can be used. However, welded joints have the disadvantage of requiring skilled workers as well as having negative health and safety and environmental implications. For example, the construction of a gas conveying pipeline made from 40 metre long lengths of steel pipe, and with a 1 metre diameter, conventionally use welded joints. Each joint can take a skilled team a whole day to make, when taking into consideration the deployment of equipment at the joint location and inspection of the joint by X-ray equipment. Also, around 1 in 10 of such welded joints will have to be repaired after such an inspection. This makes pipelines expensive and time consuming to construct. Where plastic pipes are used, heat fused joints may be used, in which the ends of the pipes to be connected are heated up and then fused together.

[0005] Push fit couplings, welded joints and fused joints are difficult to

disconnect, for example for repair or maintenance, with such disconnection often causing damage to the pipes.

[0006] Victaulic (also known as victolic) pipe joints are known in the art, in which the pipe ends to be connected are formed with an annular groove in their external surface. An example of a Victaulic type pipe joint 100 is shown in Figure 1 and Figure 2. An annular resilient gasket 50, with a C-shaped longitudinal cross-section is placed over the pipe ends 140 and 142 to be joined, so that the gasket straddles the two pipes. Typically, the gasket is stretched slightly to fit over the pipe ends so as to form a seal between the gasket 150 and the pipes 140 and 142. The gasket is then encased by a rigid Victaulic type casing 110 and 112, which engages the grooves 136 formed in the pipe ends. Generally the casing is formed in two halves 110 and 12, formed with flanges 120 and 122 and the two halves are connected together by bolts 130 passing through the flanges 120 and 122. The casing compresses the sealing gasket 150 to further improve the seal between the gasket 150 and the pipe ends 140 and 142.

[0007] There are known problems with such Victaulic pipe joints. The first is that they are not well suited to high pressure pipe systems. In particular where one of the pipe elements coupled together by the joint comprises a pipe end cap, the joint has to withstand significant forces acting to pull the pipe ends connected by the joint apart. When fluid pressure builds up within the pipe joint of Figures 1 and 2, the pressure acts radially outwardly on the gasket, causing the gasket to inflate and apply a radially outwardly directed force to the casing halves 110 and 112. That is, the pressure acts in the direction of the double headed arrow, labelled "pressure" in Figures 1 and 2. This force acts to pull the casing halves apart, and so high fluid pressure within the pipe joint of Figure 1 is transferred to the bolts 130 holding the casing halves 110 and 112 together. Such Victaulic type pipe joints are typically rated to fluid pressures of 150psi and have been known to fail around 200psi, typically by failure of the bolts 130. [0008] In addition, pipes connected by a Victaulic type pipe joint, of the type shown in Figure 1 , may be able to rotate with respect to each other and with respect to the casing 110 and 112, which may cause problems of movement of pipe valves, etc. to inaccessible locations. Victaulic type pipe joints can also fail if the bolts come undone due to vibration of the pipe system.

Summary of the Invention

[0009] It is an aim of embodiments of the present invention to address

shortcomings with prior art pipe coupling systems, whether mentioned herein or not.

[0010] Accordingly there is provided a pipe coupling for connecting the ends of two tubular conduits comprising: an annular gasket arrangement for straddling and for forming a seal against two such conduit ends; a casing arrangement for surrounding the gasket arrangement, which casing comprises a pair of radially inwardly extending projection arrangements, each projection arrangement for engaging an annular groove formed in each such conduit end; and a fixing sleeve s!ideably mountable around the casing arrangement, wherein an outer profile of the casing arrangement is tapered and an inner profile of the fixing sleeve is correspondingly tapered, such that the fixing sleeve may only be fitted to the casing arrangement in one direction and whereby the fixing sleeve and casing arrangement comprise fixing means to secure the fixing sleeve in position on the casing arrangement.

Brief Description of the Drawings

[0011] For a better understanding of the invention, and to show how

embodiments of the same may be carried into effect, reference will now be made, by way of example, to the accompanying diagrammatic drawings in which:

[0012] Figures 1 and 2 show a prior art Vtctaulic-type pipe coupling arrangement;

[0013] Figure 3 shows a cross-sectional view of a pipe coupling according to an embodiment of the present invention;

[0014] Figure 4 shows a cross-section through part of a casing arrangement forming part of a pipe coupling according to an embodiment of the present invention; [0015] Figure 5 shows a cross-section through part of a fixing sleeve forming part of a pipe coupling according to an embodiment of the present invention;

[0016] Figure 6 shows a cross-sectional view of an intermediate step in the assembly of the pipe coupling shown in Figure 3.

[0017] Figure 7 is an exploded isometric view of a pipe coupling assembly according to a second embodiment of the present invention;

[0018] Figure 8 is a side view of the pipe coupling assembly of figure 7;

[0019] Figure 9 is a side sectioned view of the second embodiment of the present invention shown in figure 7;

[0020] Figure 10 is a longitudinal cross sectional view of a pipe coupling, in accordance with a third embodiment of the present invention;

[0021] Figure 1 1 is a perspective view of the pipe coupling of figure 10, when assembled;

[0022] Figure 12 is a longitudinal cross-sectional view of a pipe coupling, in accordance with a fourth embodiment of the present invention;

[0023] Figure 13 is a perspective view of the pipe coupling of figure 12, when assembled;

[0024] Figure 14 is an isometric exploded assembly view of a pipe coupling, in accordance with a fifth embodiment of the present invention;

[0025] Figure 15 is an isometric view of the pipe coupling of figure 1 , when assembled;

[0026] Figure 16 is a side elevation view of the pipe coupling assembly of figure 14;

[0027] Figure 17 is a cross- sectional view of the pipe coupling assembly of figure 14;

[0028] Figure 18 is a side view of a pipe coupling in accordance with a sixth embodiment of the present invention;

[0029] Figure 19 is a cross-sectional side view of the pipe coupling of figure 18 taken along a centered longitudinal axis identified by section line 19— 19, including a magnified section of functional components of the coupling; [0030] Figure 20 is an isometric exploded view of a pipe coupling according to a seventh embodiment of the present invention;

[0031] Figure 21 is an isometric view of the pipe coupling of figure 20, when assembled;

[0032] Figure 22 is a cross-sectional view of the pipe coupling of figure 20, taken along a centered longitudinal axis identified by section line 22— 22 in figure 21 , including a magnified view of functional components;

[0033] Figure 23 is an end elevation assembled view of the pipe coupling of figure 21 ;

[0034] Figure 24 is a cross-sectional view of the pipe coupling of figure 21 and taken along a centered longitudinal axis identified by section line 24— 24 of figure 23, including a magnified section of a latching feature of the coupling;

[0035] Figure 25 is a cross-sectional view of a pipe coupling according to an eighth embodiment of the present invention, including a magnified section of a pipe clamping feature of the coupling; and

[0036] Figure 26 is a cross-sectional view of a pipe coupling according to a ninth embodiment of the present invention, including a magnified section of a pipe gripping feature of the coupling.

Detailed Description of the Preferred Embodiments

[0037] Like reference numerals refer to like parts throughout the various views of the drawings.

[0038] Figure 3 shows a cross-sectional view through a pipe coupling according to an embodiment of the present invention. The pipe coupling comprises a gasket 250 for sealing the ends of pipes 240 and 242. It further comprises a pair of casing halves 210, 212 which sit around the gasket 250 and protrude into grooves 236 formed adjacent the end of each pipe 240, 242.

[0039] Surrounding the casing arrangement is a fixing sleeve 260, which holds the casing halves 210, 212 together and compresses the joint formed between the pipe. [0040] The gasket 250 is an annular gasket with a C-shaped longitudinal cross- section and may be of any kind known in the art for use in a Victaulic (or victolic) pipe joint. The gasket 250 is made of resilient sealing materia! and may, for example, be moulded of natural or synthetic rubber. Other material from which the gasket may be made include, ethylene propylene diene monomer (EPDM) {generally used where the transported fluid is water), a nitrile compound (generally used where the transported fluid is oil), fluoro-eiastomer, neoprene, white nitrile and epichlorohydrin.

[0041] The casing halves 210, 212 are made of a rigid material and each are shaped generally as a half-annulus with a C-shaped longitudinal cross-section. Two end portions 222, 224 of the casing halves (see Figure 4) extend radially inwardly of a half- cylinder shaped main body 225 of the casing halves. The end portions 222, 224 have a width and an internal diameter matching the width and the external diameter of the grooves 236 formed in the pipe ends 240, 242 so that the end portions fit into the grooves, when the casing halves 210, 212 are fitted over the gasket 250, as is shown in Figure 3.

[0042] The end portions 222 and 224 are arranged to have different outer radii so that the outer profile of the casing half tapers from a larger radius R1 at end portion 222 to a smaller radius R2 at end portion 224. When the two casing halves 210, 212 are assembled around the pipe ends 240, 242 the appearance of the casing arrangement is frusto-conical i.e. resembling a truncated cone.

[0043] In the embodiment shown in Figures 3 to 6, the change in radius from first end portion 222 to second end portion 224 is linear. In alternative embodiments, the change in radius from first to second end portions may change in a non-linear manner.

[0044] The cylindrical fixing sleeve 260, shown in Figure 5, is made of a rigid material and is dimensioned to fit slideably over the two casing halves 210, 212 when the casing halves are mounted over the gasket 250, as shown in the intermediate step illustrated in Figure 6. In one embodiment, shown in Figure 3, the fixing sleeve 260 fits over the casing halves 2 0, 212. As the fixing sleeve is urged into position, which may require the use of a tool such as a hammer or mallet, the two casing halves 210, 212 are pushed inwardly so as to push up against the gasket and improve the sealing of the gasket to the pipes 240, 242. This also has the effect of improving the engagement between the toothed 232 end portions 222, 224 of the casing halves 2 0, 212 and the end portions of pipes 240, 242 so as to form a secure sealed coupling between the tubular conduits.

[0045] Once the fixing sleeve 260 has been applied to the casing arrangement 210, 212, noting that it can only be fitted one way, due to the tapering outer profile of the casing arrangement and corresponding tapering of the inner profile of the fixing sleeve, the point at which full engagement has been achieved will be noted by the fitter as the fixing sleeve clicks into position and is retained there by means of mutually

interengaegable fixing means 226, 276.

[0046] First fixing means 226 is provided on edge of casing halves 210, 212 and takes the form of a resilient projection having a hook extending therefrom. When the fixing sleeve 260 is positioned over the casing arrangement, it will ultimately reach a position where the hook of fixing means 226 clicks into position in annular recess 276 provided at one end of fixing sleeve 260.

[0047] In this way, once the fixing sleeve 260 has been properly fitted, it will not easily separate as the mutually co-operating fixing means 226, 276 act to hold the fixing sleeve 260 firmly in position.

[0048] In the embodiment shown here, the fixing means 226, 276 are provided at the end of the casing arrangement having the smaller radius R2. However, the fixing means 226, 276 could equally be provided at the opposite end. As a further alternative, the resilient projection 226 could be provided midway along the outer profile of the casing halves 210, 212 and a corresponding groove 276 could be provided at a corresponding position on the inner surface of the fixing sleeve 260.

[0049] Advantageously, if the pipe coupling required disassembly at some future time, then the fixing means 226, 276 may be deactivated by a tool such a screwdriver or chisel, and the fixing sleeve may simply be slid away, in a reversal of the fitting process. This, of course would not be possible if the fixing means 226, 276 are provided at a midway point as described previously, although such a configuration could be used in secure environments where the pipe coupling cannot then be easily disassembled. [0050] In a further advantageous development, once properly assembled, there are no protrusions from the completed coupling, as can be seen from Figure 3. This is particularly important when the coupling is used on large-scale pipelines, such as large- diameter oil pipelines, where the entire pipeline can move significantly in use, due to expansion/contraction effects caused by temperature differences. Protrusions from prior art pipe couplings which can become entangled with the ground or other structures can be torn off or damaged. The lack of any sudden discontinuity from pipe couplings according to embodiments of the present invention substantially obviates this problem.

[0051] A further exemplary embodiment is presented and referred to as coupling assembly 300. The coupling assembly 300 is illustrated in FIGS. 7 through 9. Like features of coupling assembly 300 and coupling assembly 200 are numbered the same except preceded by the numeral "3".

[0052] Distinctions between the coupling assembly 300 and the coupling assembly 200 are detailed herein and best illustrated in FIG. 9. The exterior surface of the fixing sleeve 360 is tapered, whereas the exterior surface of the fixing sleeve 260 comprises a cylindrical surface. The gasket 350 includes a tapered gasket sidewal! 354, wherein the tapered gasket sidewali 354 expands outward as the sidewall extends inward. The interior shape of the gasket receiving feature 330 (see figure 7) includes tapered sidewalls, adhering to the contour of the gasket 350. The sleeve fixing means 326 can be cantitevered in accordance with the configuration of the sleeve fixing means 226 as previously illustrated, a mechanically biased element, such as a spring loaded pin, and the like.

[0053] Referring now to Figures 10 and 11 , there is shown a further embodiment of a pipe coupling. The pipe coupling comprises a sealing element 40 along with the casing element of two halves 8, 10 for surrounding the sealing element 40 and having two radially inwardly extending groove-engagement end portions 18, 20, a casing sleeve 12, and fixing means 58. In this case, the sealing element 40 includes a retainer 42 in which a gasket or two spaced gaskets or O-rings 44 are held. The retainer 42 includes a rigid retainer body 46 having a bore 48 for receiving as a close fit the pipe ends 2, 4, and which extends radially beyond the O-rings 44, and longitudinally to overlap the O-rings 44. Inner annular grooves 50 are formed in axially spaced relationship in the surface of the bore 48, so that at least one O-ring 44 seats on its respective pipe between the pipe end 2, 4 and the corresponding groove 22.

[0054] Preferably, the retainer body 46 is formed in two annular halves 46a, 46b, similarly to the casing halves 8, 10. This allows the O-rings 44 to be initially slid onto their respective pipe ends 2, 4, and then the retainer body 46 to be located therearound seating the O-rings in their respective annular grooves 50.

[0055] As an alternative, the retainer body 46 may be integrally formed as one- piece, and with the O-rings 44 prelocated within their annular grooves 50, may be received onto the pipe ends 2, 4 in a sliding push-fit manner.

[0056] With the retainer body 46 bridging and straddling the pipe ends 2, 4, the casing halves 8, 10 can be clamped around the retainer 42 by the fixing sleeve 12, whereby the groove-engagement end portions 18, 20 engage with the pipe grooves 22. The radial and axial extents of the retainer body 46 are received within a

complementary retainer recess 52 formed in the inner surface 54 of the casing halves 8, 10. The retainer recess 52 is spaced axially of the groove-engagement end portions 18, 20 so as to lie therebetween, preferably in spaced relationship.

[0057] The fixing means 58 again prevents or limits unintentional disengagement of the fixing sleeve 2 from the casing halves 8, 10. The fixing means 58, although may be as described previously, in this case is a locking tab preferably integrally formed as one-piece on one or each casing half 8, 10. The locking tab 58 is formed on the smaller diameter end of the respective casing half 8, 10, thereby projecting axially and radially outwardly. In another embodiment the locking tab is formed on the larger diameter end of the respective casing half. As can be seen from figure 10 there is no recessed area below the locking tab 58, unlike the cantilevered fixing means 226 shown in figure 3.

[0058] The locking tab may be ramped from the outer surface of the casing half 8, 10. In use, the fixing sleeve 12 slides over the locking tab at least in part, and once the point of interference is reached or wedging engagement occurs, the opposite end of the fixing sleeve 12 is struck, for example, with a hammer, mallet or other suitable striking implement, urging the fixing sleeve 12 into further wedging engagement with the casing halves 8, 10 via the locking tab 58. The fixing sleeve 12 is thus held securely in place, and can be released by using a tool to drive the sleeve back out of wedging engagement with the casing halves 8, 10.

[0059] The use of the retainer 42 allows the clamping pipe coupling to be formed from plastics, if needs be, since the load transfer across the joint is now primarily longitudinal or axial.

[0060] Referring to Figures 12 and 3, there is shown a further embodiment of a pipe coupling. Like references again refer to parts which are similar to those described previously, and therefore further detailed description is omitted. This embodiment of the pipe coupling comprises the sealing element 40 along with the aforementioned parts being the casing element of two halves 8, 10 for surrounding the sealing element 40 and having the two radially inwardly extending groove-engagement end portions 18, 20, the fixing sleeve 12, and the fixing means 58.

[0061] By forming the O-rings 44 from metal, such as stainless steel, instead of plastics or rubber as in the second embodiment, allows the retainer body 46 to have a smaller radial extent in comparison with that of the second embodiment. This also allows the casing halves 8, 0 to have a smaller radial extent, thereby allowing the entire coupling to have a slimline appearance. This is particularly beneficial for applications having limited installation space.

[0062] In the embodiments described above in figures 10 to 13, it may be beneficial for the retainer body 46 to have a radially inwardly projecting pipe-end stop 56, as seen in figure 13. This, ensures equal pipe end spacing and optimal seating of the O-rings 44.

[0063] As also indicated above, it may be beneficial to mount two O-rings or gaskets on each pipe end 2, 4, and in this case the retainer body 46 may be modified to include four spaced apart annular grooves 50, two being either side of the pipe-end stop 56 if provided. Furthermore, it may be advantageous to include a further seal, such as an 0-ring or gasket, between the opposing surfaces of the groove-engagement end portions 18, 20 and the grooves 22. For example, the radially inner surface of each groove-engagement end portion may include an annular groove for seating an O-ring which would then seal on the radially inner surface of the respective groove 22, once the pipe coupling was assembled.

[0064] A further exemplary embodiment is presented and referred to as coupling assembly 400. The wedge style coupling assembly 400 is illustrated in FIGS. 14 through 17. Like features of wedge style coupling assembly 400 and coupling assembly 200 are numbered the same except preceded by the numeral "4".

[0065] Distinctions between the coupling assembly 400 and the coupling assembly 200 are detailed herein and best illustrated in FIG. 17. In this exemplary embodiment, the pipe sections 440, 442 are sized and shaped for an overlapping junction therebetween. The first casing member 410 includes a coupling ridge 436 for engaging with one of the pipe sections 440, 442 and a casing member groove 438 for engaging with the mating pipe section 440, 442. A coupling groove 446 is formed proximate to a coupling end of one of the pipe sections 440, 442. A pipe coupling ridge 448 is formed proximate to a coupling end of the other pipe section 440, 442. A gasket 450 is inserted within an interior portion of a pipe coupling ridge 448. In the exemplary embodiment, gasket 450 is an O-ring. The smaller of the pipe sections 442 is inserted into the interior of the larger of the pipe sections 440. The gasket 450 provides a seal between the interior surface of the first pipe section 440 and the exterior surface of the second pipe section 442. The casing members 410, 412 are placed over the joined piping sections 440, 442, seating the coupling ridge 436 into the coupling groove 446 and the pipe coupling ridge 448 into the casing member groove 438. The interfacing configuration applies pressure to the gasket 450. The interfacing configuration also provides mechanical stability along a longitudinal axis of the piping assembly.

[0066] A further exemplary embodiment is presented and referred to as a ripple latching, wedge style coupling assembly 500. The ripple latching, wedge style coupling assembly 500 is illustrated in the illustrations presented in FIGS. 18 and 19. Like features of ripple latching, wedge style coupling assembly 500 and wedge style coupling assembly 300 are numbered the same except preceded by the numeral "5".

[0067] Distinctions between the ripple latching, wedge style coupling assembly 500 and the wedge style coupling assembly 300 are detailed herein and best illustrated in FIG. 19. A compression receiving surface 520 of the casing halves includes a circumferential ridge 528 formed about an exterior circumference of the casing members 510, 512. The casing/fixing sleeve interior surface 570 includes a

circumferential recess 578 formed about a circumference thereof.

[0068] The circumferential ridge 528 engages with the circumferential recess 578 retaining the casing sleeve interior surface 570 in position against the compression receiving surface 520. Although the circumferential ridge 528 is shown as a protrusion and the circumferential recess 578 is shown as a recession, it is understood the reverse can be employed. The circumferential ridge 528 and respective circumferential recess 578 can include a series of ridges and recessions allowing the final engagement position to adjust for optimization accordingly.

[0069] A further exemplary embodiment is presented and referred to as a wedge style coupling assembly 600. The wedge style coupling assembly 600 is illustrated in the illustrations presented in F!GS. 20 through 24. Like features of wedge style coupling assembly 600 and wedge style coupling assembly 300 are numbered the same except preceded by the numeral "6". Distinctions between the wedge style coupling assembly 600 and the wedge style coupling assembly 300 are detailed herein. The casing members 610, 612 are initially assembled about pipe sections 640, 642 using at least one cable tie styled interface. The at least one cable tie styled interface includes an assembly latching tape portion 680 extending from an edge of the second casing member 6 2. An assembly latching tape toothed section 682 is provided upon an elongated surface of the assembly latching tape portion 680. An assembly latching tape ratchet 684 is provided upon the first casing member 610 enabling insertion of the assembly latching tape portion 680 thereinto. As the assembly latching tape portion 680 passes through the assembly latching tape ratchet 684, the assembly latching tape toothed section 682 engage with a ratchet tooth 686. The ratchet tooth 686 extends downward from a canti!evered element of the assembly latching tape ratchet 684. The ratchet tooth 686 is designed to provide a ratcheting function. The ratcheting function allows teeth of the assembly latching tape toothed section 682 to pass across the ratchet tooth 686 during an insertion direction, while deterring an opposite or removal direction of the assembly latching tape portion 680 therefrom. Upon final seating of the assembly latching tape portion 680 within the assembly latching tape ratchet 684, any excessive portion of the assembly latching tape portion 680 is singulated and discarded therefrom.

[0070] In the exemplary embodiment, the wedge style coupling assembly 600 includes a pair of cable tie styled interfaces; a first cable tie styled interface located at a first end of a larger radiused end 622 of the casing members 610, 612 and a second cable tie style interface located at an opposite end of a smaller radiused end 624 of the casing members 610, 612. This configuration balances applied securing forces between the casing members 610, 612.

[0071] The casing sleeve 660 is retained upon the compression receiving surface 620 of casing halves 610, 612 in an engaging configuration by an at least one mating sleeve engaging feature 676. The at least one mating sleeve engaging feature 676 is adjustably biased enabling an engaging end to outwardly adjust during assembly. A sleeve engaging circumferential recess 626 is provided about a circumference of the compression receiving surface 620 proximate the larger radiused end 622. The engaging end of the mating sleeve engaging feature 676 adjusts outwardly during a sliding assembly process until engaging with the sleeve engaging circumferential recess 626. The exemplary embodiment includes a pair of mating sleeve engaging features 676 located at opposite sides of the compression sleeve 660 providing equal retention forces at opposite sides thereof. The compression ring biased latching element 676 can be integrated into the pressure application sleeve interior surface 670 during a molding process or provided a separate component and subsequently assembled thereto.

[0072] A further exemplary embodiment is presented and referred to as a wedge style coupling assembly 700. The wedge style coupling assembly 700 is illustrated in the sectioned illustration presented in FIG. 25. Like features of wedge style coupling assembly 700 and wedge style coupling assembly 300 are numbered the same except preceded by the numeral "7". Distinctions between the wedge style coupling assembly 700 and the wedge style assembly coupling assembly 300 are detailed herein. The wedge style coupling assembly 700 comprises features that draw mating edges 741 , 743 of the two pipe sections 740, 742 together. The pipe sections 740, 742 include a coupling ridge 736 provided about an exterior circumference. The casing members 710, 712 include a pair of coupling grooves 746 provided about an interior circumference. The coupling grooves 746 are located to mate with the coupling ridge 736 of the pipe sections 740, 742. The coupling grooves 746 include an angled surface for engagement with a mating angled surface of the coupling ridge 736. As the compression sleeve 760 is slideab!y assembled over the casing members 710, 712, the angle provided between the coupling groove 746 and the coupling ridge 736 urges the two pipe sections 740, 742 together. The specific angle can vary and would be determined during the design and engineering process of the wedge style coupling assembly 700.

[0073] The gasket 750 includes a gasket pipe edge sealing section 756, which extends radially inward for insertion between the pipe section mating edges 741 , 743. The gasket pipe edge sealing section 756 creates a seal between the pipe section mating edges 741 , 743. An outer section of the gasket 750 provides a secondary seal therebetween. The gasket pipe edge sealing section 756 is sized and shaped to create an adequate seal between the pipe section mating edges 741 , 743 without interfering with flow of fluid within the pipe sections 740, 742.

[0074] A further exemplary embodiment is presented and referred to as a wedge style coupling assembly 800. The wedge style assembly coupling assembly 800 is illustrated in the sectioned illustration presented in FiG. 26. Like features of wedge style coupling assembly 800, wedge style coupling assembly 700, and wedge style coupling assembly 300 are numbered the same except preceded by the numeral "8". Distinctions between the wedge style coupling assembly 800 and the wedge style coupling assembly 300 are detailed herein. The wedge style coupling assembly 800 comprises a mechanical interface that grips the exterior surface of the pipe sections 840, 842. The mechanical interface utilizes a series of grasping teeth 836 provided partially or completely about an external circumference of the pipe sections 840, 842 proximate each mating end thereof. A mating series of engaging teeth 846 are provided upon an interior mating surface of the casing members 810, 812. The series of engaging teeth 846 are located to align and interface with the grasping teeth 836. As the compression sleeve 860 is slideably assembled over the casing members 810, 812, the engaging teeth 846 mate with the grasping teeth 836, mechanicaliy securing the two pipe sections 840, 842 together. It is recognized that the engaging teeth 846 and the grasping teeth 836 may be formed by a thread forming process, providing a helical spiral along each surface. The threading may be similar for each side of the pipe sections 840, 842, or where the first pipe section 840 comprises standard threading and the second pipe section 842 comprises reverse threading. This enables the installer to axiai!y adjust each pipe coupling as needed.

[0075] The casing members and the compression sleeves and respective components can be fabricated of an injection molded materia), such as plastic.

Alternately, the casing members and the compression sleeves can be fabricated of a metal, a composite material, or any other materials suitable for the designed

embodiment and subsequent application. The casing members and the compression sleeves can be of similar or different materials. The seal or gasket is preferably fabricated of a molded rubber, nylon, or like pliant materia! suitable for creating a reliable seal between two adjoining pipe sections.

[0076] A noted advantage of the coupling assembly 200, 300, 400, 500, 600 is the ability to disassemble the pipe coupling. Referencing the coupling assembly 200 as an example, the service individual would separate the sleeve engaging member 226 and the mating sleeve engaging feature 276. This can be accomplished using any reasonable tool, a screwdriver, a chisel, and the like. Once disengaged, the service person would apply a separation force to the larger diameter end 272 of the

compression sleeve 260 to reverse the fitting process. Embodiments of the present invention find utility in a range of different pipe environments, ranging from small-bore pipes used in domestic situation up to large diameter pipes used in the transportation of oil, gas or water. Depending on the characteristics of the pipe, the materials used to manufacture the pipe coupling will vary. In some circumstances, the various

components of the pipe coupling can be formed from a plastics material, such as glass- filled nylon. In other circumstances, the components can be formed from steel, another metal or an alloy. [0077] Embodiments of the present invention find utility in a range of different pipe environments, ranging from smail-bore pipes used in domestic situation up to large diameter pipes used in the transportation of oil, gas or water. Depending on the characteristics of the pipe, the materials used to manufacture the pipe coupling will vary. In some circumstances, the various components of the pipe coupling can be formed from a plastics material, such as glass-fil!ed nylon. In other circumstances, the components can be formed from steel, another metai or an alloy.

[0078] The pipe coupling according to the present invention may be a coupling for connecting two lengths of pipe. Alternatively, the pipe coupling according to the present invention may be a coupling for connecting a length of pipe to a pipe joint assembly. Many types of pipe joint assemblies are known, for example pipe joint assemblies for connecting three lengths of pipe in a T-junction, pipe end caps and pipe joint assemblies incorporating valves or other elements known in the art.

[0079] Attention is directed to all papers and documents which are filed concurrently with or previous to this specification in connection with this application and which are open to public inspection with this specification, and the contents of all such papers and documents are incorporated herein by reference.

[0080] All of the features disclosed in this specification (including any

accompanying claims, abstract and drawings), and/or ail of the steps of any method or process so disclosed, may be combined in any combination, except combinations where at least some of such features and/or steps are mutually exclusive.

[0081] Each feature disclosed in this specification (including any accompanying claims, abstract and drawings) may be replaced by alternative features serving the same, equivalent or similar purpose, unless expressly stated otherwise. Thus, unless expressly stated otherwise, each feature disclosed is one example only of a generic series of equivalent or similar features.

[0082] The invention is not restricted to the details of the foregoing

embodiment(s). The invention extends to any novel one, or any novel combination, of the features disclosed in this specification (including any accompanying claims, abstract and drawings), or to any novel one, or any novel combination, of the steps of any method or process so disclosed.

[0083] The pipe coupling according to the present invention may be a coupling for connecting two lengths of pipe. Alternatively, the pipe coupling according to the present invention may be a coupling for connecting a length of pipe to a pipe joint assembly. Many types of pipe joint assemblies are known, for example pipe joint assemblies for connecting three lengths of pipe in a T-junction, pipe end caps and pipe joint assemblies incorporating valves or other elements known in the art.

[0084] Since many modifications, variations, and changes in detail can be made to the described preferred embodiments of the invention, it is intended that all matters in the foregoing description and shown in the accompanying drawings be interpreted as illustrative and not in a limiting sense. Thus, the scope of the invention should be determined by the appended claims and their legal equivalence.