GB2379252A

GB2379252A - A pipe coupling or flange adapter.

Info

Publication number: GB2379252A
Application number: GB0117456A
Authority: GB
Inventors: Darren Paul Davis
Original assignee: Saint Gobain Pipelines PLC
Current assignee: Saint Gobain PAM UK Ltd
Priority date: 2001-07-18
Filing date: 2001-07-18
Publication date: 2003-03-05
Also published as: GB0117456D0

Abstract

A pipe coupling or flange adapter (10,50) comprises an end ring (11) and at least a first, annular, elastomeric sealing member (12), the end ring (11) and the said sealing member (12) being engageable one with the other and lying adjacent one another in the longitudinal direction of the coupling or adapter. The sealing member defines a face (17) and the end ring defines a seating (16) that is engageable with the face, the seating (16) having formed therein a plurality of recesses (18) and the first face having protruding therefrom a corresponding plurality of protuberances (19). The protuberance each lie in use of the coupling or adapter in a said recess and are of complementary shape thereto. Advantageously on compression of the coupling or adapter in its longitudinal direction each said protuberance (19) moves further into its associated recess (18) to anchor part of the sealing member thereto.

Description

A PIPE COUPLING OR FLANGE ADAPTER This invention relates to a pipe coupling or flange adapter.

A pipe coupling is commonly used for connecting together two consecutive lengths of eg. PVC steel, cast iron/ductile iron or copper water pipe; or for connecting a length of water pipe to for example a valve or actuator. A typical pipe coupling includes a pair of end rings that respectively encircle each of the pipes requiring connection. The end rings are interconnected by an annular series of nut and bolt combinations. Between the end rings a cylindrical coupling body encircles the ends of the pair of pipes so as to cover the discontinuity that would otherwise be apparent.

Between each end ring and the adjacent end of the coupling body the pipe coupling typically includes an annular, elastomeric sealing member the initial diameter of which permits insertion of one of the pipe ends therethrough. The sealing member includes at least one tapered surface on its exterior, that engages with a correspondingly tapered interior surface defined by a bell-mouthed end of the coupling body. On tightening of the nuts and bolts the end rings are drawn together, with the result that the aforementioned tapers cause driving of the elastomeric sealing member into sealing engagement with the exterior periphery of the adjacent water pipe.

A flange adapter is similar to a pipe coupling, except that a flange ring replaces one of the end rings, the coupling body and one of the annular sealing members. The purpose of the flange adapter is to permit securing to a length of water pipe, eg. an elbow, expansion joint or valve.

One problem in the assembly of pipe couplings and flange adapters of the kind described hereinabove is that the outside diameters of the lengths of

pipe to which such assemblies are connected may differ from one pipe length to another. Therefore a pipe coupling or flange adapter of a given nominal size must exhibit a wide tolerance in the sense of being able to accommodate a range of actual outside diameters of the pipes.

To a certain degree the resilient deformability of the elastomeric materials from which the sealing members commonly are made provides such diameter tolerancing. However, both current pipe coupling and flange adapter arrangements can accommodate only a 15 to 17mm tolerance band of the outside diameters of the water pipes.

There is a need for pipe couplings and flange adapters that exhibit a wider tolerance band.

One proposal is to provide an arrangement that anchors part of the sealing member relative to an adjacent end ring on tightening of the series of bolts.

Two versions of this proposal are known in the prior art.

In one version the end ring defines a seating for a radially extending face of the sealing member. The radially extending face includes an annular groove. An annular rib of corresponding profile protrudes from the surface of the seating defined in the end ring.

However, in use of this design of pipe coupling or flange adapter, there is a tendency for the groove and the rib to become mis-aligned such that the rib ceases to serve the purpose of anchoring the sealing member relative to the end ring.

In another proposal the seating defined in the end ring includes an annular

series of protuberances protruding therefrom.

The radially extending face of the sealing member includes a correspondingly sized and located series of recesses, into which the protuberances fit on tightening of the pipe coupling or flange adapter.

This arrangement suffers from a similar defect to the rib and groove arrangement described hereinabove, in that there is a tendency for the protuberances and recesses to become disengaged from one another thereby preventing effective anchoring.

The tendency of the prior art arrangements to provide inadequate anchoring is believed to worsen as the torque applied to the nuts of the pipe coupling or flange adapter are tightened.

According to a first aspect of the invention there is provided a pipe coupling or flange adapter comprising an end ring and at least a first, annular, elastomeric sealing member, the end ring and the said sealing member being engageable one with the other and lying adjacent one another in the longitudinal direction of the coupling or adapter, the sealing member defining a first face and the end ring defining a seating that is engageable with the first face, the seating having formed therein a plurality of recesses and the first face having protruding therefrom a corresponding plurality of protuberances, each said protuberance lying in use of the coupling or adapter in a said recess and being of complementary shape thereto, whereby on compression of the coupling or adapter in its longitudinal direction each said protuberance moves further into its associated recess to anchor part of the sealing member thereto.

An advantage of this arrangement is that as the nut and bolt combinations

are tightened to shorten the pipe coupling or flange, 1 apter, the protuberances on the first face are driven increasingly further into the recesses.

By virtue of the elastomeric nature of the material of the sealing ring, the protuberances therefore extrude into the recesses. Consequently the anchoring force increases with increased tightening of the nut and bolt combinations.

Preferably the sealing member includes a pipe engaging end that is remote from the first face, the pipe engaging end being resiliently deformable into sealing engagement with a pipe on compression of the coupling or adapter in its longitudinal direction.

In other words the firm anchoring provided by the arrangement of the invention allows the edge of the sealing member remote from the end ring to roll radially towards the pipe, under the influence of an engaged pair of tapered surfaces as described hereinabove.

The more tightly the first face of the sealing member is anchored relative to the seating the further it is possible for the aforementioned remote edge of the sealing member to roll inwardly, with the result that the arrangement of the invention is highly effective at coupling or adapting water pipes over a wider tolerance band than has previously been possible.

In preferred embodiments of the invention each protuberance tapers in the longitudinal direction of the coupling or adapter, away from the first face.

Tapering of the protuberances ensures their correct location in the recesses, with the result that the aforementioned driving and extrusion of the

protuberances occurs so as to maximise the anchoring force acting on the sealing ring in the vicinity of the first face. Consequently there is a reduced risk of the anchoring failing in the manner of the prior art arrangements.

Conveniently each protuberance includes a region of oval transverse cross section.

This feature advantageously allows an arrangement that includes a minimal number of the protuberances whilst simultaneously generating the anchoring effect over the entirety of each quadrant of the first face of the sealing member.

In an alternative arrangement it is possible, within the scope of the invention, to employ protuberances of circular transverse cross section.

However, in order to produce maximal anchoring forces there would be required a larger number of the circular cross section protuberances than the above-mentioned oval ones. There is danger in using too many circular section protuberances of creating a shear path between the associated recesses in the end ring. Consequently the use of oval protuberances and correspondingly shaped recesses is preferred.

Preferably the protuberances define an equi-spaced series extending about the said first face of the sealing member; and the recesses in the seating are each disposed so as to permit insertion thereinto of a said protuberance.

In a practical embodiment of the invention the recesses perforate the end ring. This simplifies manufacture of the end rings as cast components, and additionally provides effectively an unlimited space into which the protuberances are extrudable.

Conveniently the pipe coupling or flange adapter may include an adjustable clamp for compressing the coupling or flange in its longitudinal direction.

In one preferred embodiment, the clamp includes a further annular member that is spaced from the end ring in the longitudinal direction of the coupling or adapter; and at least one tightenable member interconnecting the end ring and the further annular member, the further annular member including a first tapered surface and the sealing member including adjacent its pipe engaging end a second tapered surface that is engageable with the first tapered surface such that in use, on compression of the coupling or adapter in its longitudinal direction, the engagement of the said tapered surfaces causes the said pipe engaging end to deform into sealing contact with a pipe.

This arrangement is particularly suitable as the construction of a flange adapter.

Alternatively the clamp may include a further annular member that is spaced from the end ring in the longitudinal direction of the coupling or adapter; at least one tightenable member interconnecting the end ring and the further annular member; and an annular body lying between the end ring and the further annular member, the annular body including a first tapered surface and the sealing member including adjacent its pipe engaging end a second tapered surface that is engageable with the first tapered surface such that in use, on compression of the coupling or adapter in its longitudinal direction, the engagement of the said tapered surfaces causes the said pipe engaging end to deform into sealing contact with a pipe.

This arrangement is more suitable as the construction of a pipe coupling.

Conveniently the aforesaid assembly may optionally include a further, annular, elastomeric sealing member that is spaced from the first said sealing member in the longitudinal direction of the coupling or adapter, the annular body including a third tapered surface and the further sealing member including a fourth tapered surface that is engageable with the third tapered surface such that in use, on compression of the coupling or adapter in its longitudinal direction, the engagement of the said tapered surfaces causes the said pipe engaging end of the further sealing member to deform into sealing contact with a pipe.

This arrangement defines further features suitable for inclusion in a pipe coupling.

Preferably the or each shortenable member is selectively shortenable to cause the said compression of the coupling or adapter. This feature advantageously suits constitution of the shortenable members as a series of bolt and nut combinations interconnecting the end rings (of the pipe coupling) ; or an end ring and a flange ring (of a flange adapter).

Preferably the or each sealing ring includes a radially inner surface for engaging a pipe, the radially inner surface including one or more formations for enhancing its engagement with a said pipe.

In one embodiment the formations are in the form of annular ribs, annular barbs, or a combination of different formation types.

The formations that are defined as annular barbs may if desired be angled or otherwise directed or biased to oppose any tendency of the sealing member to creep relative to a part of the pipe to which it is secured in use.

There now follows a description of preferred embodiments of the invention, by way of non-limiting example, with reference being made to the accompanying drawings in which: Figure 1 is a side elevational, partly sectioned view of a pipe coupling according to the invention, showing the components thereof in exploded form; Figure 2 is a side elevational, partly sectioned view of the components of Figure 1 in the configuration they would adopt in use of the pipe coupling, but for clarity omitting the coupled pipes; Figure 3 is an end elevational view, taken from one end, of the pipe coupling of Figures 1 and 2 in order to show a preferred pattern of recesses and bolt holes; Figure 4 is a view, similar to the Figure 1 view, showing the components of a flange adapter according to the invention; Figure 5 shows the Figure 4 components in the configuration they would adopt when in use to secure the flange adapter to a pipe but omitting for clarity the pipe itself ; and Figure 6 is an end elevational view of the flange adapter of Figures 4 and 5, showing the preferred pattern of recesses, the bolt hole pattern and the preferred pattern of flange holes.

Referring to the drawings and in particular to Figures 1 to 3 there is shown a pipe coupling 10 comprising a first end ring 11 and a first, annular, elastomeric sealing member 12.

First end ring 11 and first sealing member 12 are concentric with one another and each have a central bore that is large enough to encircle a water pipe as described hereinabove.

End ring 11 includes an annular flange 13 having formed integrally

therewith a forwardly extending annular skirt 14 that defines a hollow, cylindrical portion of the end ring 11. Flange 13 extends radially inwardly of the skirt 14, about the entire annulus thereof.

The interior diameter of the cylindrical portion defined by skirt 14 is slightly greater than the maximum outer diameter of elastomeric sealing member 12, whereby sealing member 12 is snugly receivable within the end ring 11. In other words the sealing member 12 and the end ring 11 are engageable one with the other such that they lie adjacent one another in the sense of the longitudinal direction of the pipe coupling 10.

The portion of annular flange 13 lying on the same side of end ring 11 as sealing member 12 defines a seating 16.

The portion of sealing member 12 that lies adjacent seating 16 defines a first face 17 that is engageable with seating 16.

Seating 16 has formed therein a circular series of recesses 18 that in the preferred embodiment shown perforate the annular flange 13.

In other embodiments of the invention the recesses 18 need not, depending on the thickness of the flange 13, perforate the latter.

A plurality of protuberances 19 protrude from the first face 17 towards the recesses 18.

As is apparent in Figure 3, the recesses 18 define a regularly spaced series of oval apertures that are substantially identical to one another. The transverse cross sections and the locations of the protuberances 19 are complementary to the shape and location of the recesses 18 whereby on

assembly of the sealing member into the hollow cylindrical interior of the end ring 11 against the seating 16 each protuberance 19 is received in an associated said recess 18.

As shown, each protuberance 19 tapers in the longitudinal direction of the coupling away from the first face 17 (ie. towards the recesses 18). Each protuberance 19 is truncated so as to be flat-ended as shown.

The sealing ring 12 defines an essentially hollow, cylindrical interior 21 defined by the essentially annular construction thereof.

The annular wall of sealing member 12 is substantially parallel sided over approximately half its length in the longitudinal direction of the pipe coupling. The portion of the exterior wall of sealing member 12 adjacent the end thereof that is remote from seating 16 is on the other hand tapered as indicated by reference numeral 23 in Figure 1. The end of sealing member 12 remote from seating 16 therefore defines a pipe engaging end that, by virtue of the manufacture of the sealing member 12 from an elastomeric, or other resiliently deformable material is resiliently deformable into sealing engagement with a pipe (not shown) encircled by the end ring 11 and the sealing member 12.

The pipe coupling 11 additionally includes a further annular member in the form of a per se known coupling body 24.

Coupling body 24 defines an open-ended, hollow, cylindrical member the open ends 26,27 of which are bell-mouthed in order to define, at either end of the coupling body 24, an inner surface that is an inwardly directed taper 28,29.

The coupling body 24 is concentric with the sealing member 12 and end ring 11, and lies axially spaced from the end ring in the longitudinal direction of the pipe coupling 10.

The central bore of body 24 is essentially of the same diameter as the inner diameter of the flange 13 and sealing member 12.

The pipe coupling also includes a further annular member in the form of a second end ring 31 that is generally of the same construction as first end ring 11.

A second sealing member 32 is received in the hollow cylindrical interior of second end ring 31, in like manner to the receipt of first sealing member 12 in first end ring 11. Thus the face 33 defining the right hand end of second sealing member 32 in the arrangement as shown in Figures 1 and 2 abuts seating 34 of second end ring 32. Also the series of protuberances 19 extending from face 33 is receivable in the correspondingly sized, located and shaped series of recesses 18 defined in the flange member 13 of second end ring 31.

The pipe coupling 10 includes a series of shortenable members each in the form of a nut 36, washer 37 and bolt 38 combination of per se known design.

Each of the nut, washer and bolt combinations serve tightenably to interconnect the first and second end rings 11,31 by virtue of the formation at four equi-spaced locations on the outer periphery thereof of an eye 39 that is perforated to receive the shank and/or the thread of the bolt 38, such that the nut 36 and washer 37 may be assembled onto the bolt 38 in a per se known manner as illustrated in Figure 2. As is apparent from Figures 1 and

2, the eyes 39 provide aligned pairs of holes for receipt of the nut and bolt combinations.

Tightening of each nut 36 onto its associated bolt 38 causes compression of the components of the pipe coupling 10 in the longitudinal sense thereof.

Optionally, the eyes 39 formed in first end ring 11 may include eg. a longitudinal slot extending radially of the bore of each eye; and the heads of the bolts 38 may include a fillet or web interconnecting the periphery of the head and the shank of the bolt so as to be receivable in the longitudinal slot.

This arrangement prevents rotation of the bolt relative to the eye, during tightening of the nut 36, in a per se known manner.

In use the pipe coupling is assembled to the condition shown in Figure 2, with a respective pipe end passing through each end ring/sealing member combination.

On compression of the pipe coupling by tightening of the respective nuts 36 onto the bolts 38, the annular tapered inner diameter 28 of coupling body 24 will bear against the annular tapered outer diameter 23 of first sealing member 12; and similarly the taper 29 will bear against the annular outer taper 23 of sealing member 32.

By virtue of the angles of the tapers, this action will induce in each sealing ring both longitudinal and radial forces.

The longitudinal forces will act to drive each protuberance 19, that on assembly of the coupling is received in an associated one of the recesses 18, further into the adjacent recess.

This action causes extrusion of the material of the protuberances 19 into and along the recesses 18. The greater the tightening torque of the nuts 36, the greater will be the extent of extrusion.

The radial forces caused by engagement of the respective tapers cause the end of each sealing member 12,32 that is remote from the associated end ring 11,31 to flex and roll radially inwardly into sealing engagement with the external diameter of the adjacent pipe end.

Since the anchoring force derived from the longitudinal forces increases as the tightening torque of the nuts increases, and since at the same time the radial forces driving the sealing members into contact with the adjacent pipes also increases, the pipe coupling of the invention is particularly advantageous in coupling pipe ends whose diameters are less or greater than the nominal diameters to which they are purportedly manufactured.

As is evident from Figures 1 and 2, each sealing member 12,32 includes extending about its radially inner surface a series of ribs or teeth 41. The function of the ribs or teeth is to enhance gripping of the adjacent, encircled pipe end; and to improve sealing of the elastomeric sealing member thereabout.

Referring now to Figures 4 to 6 there are shown views, corresponding to the views of Figure 1, of a flange adapter 50 embodying the principles of the invention.

At is right hand end as shown in the drawings the flange adapter 50 is closely similar to the pipe coupling of Figures 1 to 3, in that the flange adapter includes an end ring 51 whose design is generally the same as that of the end rings 11,31 of Figures 1 to 3.

An elastomeric, annular sealing member 52 of generally the same design as the sealing members 12,32 of Figures 1 to 3, is received with its protuberances 59 engaged in recesses 58 formed in end ring 51, in an analogous way to the fitting of the sealing members 12,32 into the end rings in Figures 1 to 3.

The flange adapter of Figures 4 to 6 omits the coupling body 24 present in Figure 1. Instead at its left hand end the flange adapter includes a flange adapter body 53.

Flange adapter body includes an annular flange plate 54 that is perforated by a centre bore 56 of a nominal chosen diameter suitable for connection to eg. an elbow, expansion joint, valve or other component requiring coupling to a water pipe the end of which is encircled by the end ring 51 and sealing member 52. The water pipe end is omitted from Figures 4 to 6 for clarity.

Extending to the right of Figures 4 and 5, ie. towards sealing member 52, flange adapter body 53 defines a hollow, tapered, cylindrical portion 57 that terminates at an open, bell mouth 61 defining a tapered inner annular surface 62.

Tapered surface 62 is, in use of the flange adapter, engageable with the tapered outer surface 55 of the sealing member 52.

A series of nut, washer and bolt combinations 66,67, 68 are arranged in a pattern similar to that of the nut and bolt combinations of Figures 1 to 3, interconnecting the end ring 52 and the flange adapter body 53 in a compressible member.

This is achieved by virtue of receipt of the head of each bolt 68 in an eye 69 formed in the flange plate 54 such that the shank of each bolt passes through the flange plate and protrudes on the opposite side thereof ; and passage of the threaded portion of each bolt through an eye 71 formed in the flange 63 of end ring 51.

The number, size and location of the apertures in the eyes 69,71 are such as to provide pairs of aligned holes that are interconnectable by the bolts 68, in a manner similar to the bolts 38 in the embodiment of Figures 1 to 3.

As is apparent from eg. Figure 6, flange plate 54 additionally includes formed therein and passing therethrough a series of further apertures 72 whose function is to permit mating to the flange plate 54 of a further component such as the elbow, expansion joint or valve previously mentioned.

The precise pattern of the further apertures 72 may be chosen to suit the intended component to be secured to the adapter 50.

In use of the flange adapter of Figures 4 to 6 the adapter components are assembled so that the sealing member 52 is received in the end ring 51; and the flange adapter body 53 is loosely bolted to the end ring 51. The end of a water pipe is encircled by end ring 51 and sealing member 52.

The nuts 66 are then tightened onto the bolts 68 in a conventional manner, to compress the flange adapter.

This causes engagement between the respective tapered surfaces. In a similar manner to the operation of the sealing members 12,32 of Figures 1 to 3 the protuberances 59 are extruded into the recesses 58 causing a firm

anchoring of the right hand end of the sealing ring relative to the end ring 51.

Simultaneously the end of sealing member 52 remote from end ring 51 is rolled into tight sealing engagement with the end of the pipe, even if the latter has a diameter that differs from the nominal diameter of the flange adapter 4.

The sealing member 52 of Figures 4 to 6 may of course include the annular ribs 73 or other pipe gripping and sealing formations, that are similar to the ribs 41 of the sealing members 12,32 in Figure 1.

It has been found that pipe couplings and flange adapters embodying the principles of the invention may accommodate a much wider range of pipe diameter tolerances than has hitherto been the case.

The pipe couplings and flange adapters of the invention are also superior to the prior art arrangements in accommodating ovality and other forms of non-circularity of the water pipe ends.

As noted the sealing members 12,32, 52 may be manufactured from an elastomeric material.

The end rings 12,32 and 52 may typically be manufactured from so-called "ductile"iron, as may be the flange adapter body 53.

Typically the bolts, nuts and washers are manufactured from a steel whose precise specification the skilled worker may readily determine.

Similarly the coupling body 24 may be manufactured from a grade of steel

that is suitable for its intended functions.

The protuberances 19 and recesses 18 may if desired be of other cross sections than the ones described. Combinations of different protuberance types are possible in a single sealing member according to the invention.

The recesses and protuberances of a given end ring or sealing member need not all lie on the same pitch circle. Of course in such cases it is important to ensure location of the recesses so as to accommodate all the protuberances.

Claims

1. A pipe coupling or flange adapter comprising an end ring and at least a first, annular, elastomeric sealing member, the end ring and the said sealing member being engageable one with the other and lying adjacent one another in the longitudinal direction of the coupling or adapter, the sealing member defining a first face and the end ring defining a seating that is engageable with the first face, the seating having formed therein a plurality of recesses and the first face having protruding therefrom a corresponding plurality of protuberances, each said protuberance lying in use of the coupling or adapter in a said recess and being of complementary shape thereto, whereby on compression of the coupling or adapter in its longitudinal direction each said protuberance moves further into its associated recess to anchor part of the sealing member thereto.

2. A pipe coupling or flange adapter according to Claim 1 wherein the

sealing member includes a pipe engaging end that is remote from the first t face, the pipe engaging end being resiliently deformable into sealing engagement with a pipe on compression of the coupling or adapter in its longitudinal direction.

3. A pipe coupling or flange adapter according to Claim 1 or Claim 2 wherein each said protuberance tapers in the longitudinal direction of the coupling or adapter away from the first face.

4. A pipe coupling or flange adapter according to any preceding claim wherein each said protuberance includes a region of oval transverse crosssection.

5. A pipe coupling or flange adapter according to any preceding claim

wherein the protuberances extrude via the recesses on compression of the coupling or adapter in its longitudinal direction.

6. A pipe coupling or flange adapter according to any preceding claim wherein the protuberances define an equi-spaced series about the said first face; and the recesses in the seating are each disposed so as to permit insertion thereinto of a said protuberance.

7. A pipe coupling or flange adapter according to any preceding claim wherein the recesses perforate the end ring.

8. A pipe coupling or flange adapter according to any preceding claim including adjustable clamp for compressing the coupling or flange in its longitudinal direction.

9. A pipe coupling or flange adapter according to Claim 8 when dependent from Claim 2 wherein the clamp includes a further annular member that is spaced from the end ring in the longitudinal direction of the coupling or adapter; and at least one tightenable member interconnecting the end ring and the further annular member, the further annular member including a first tapered surface and the sealing member including adjacent its pipe engaging end a second tapered surface that is engageable with the first tapered surface such that in use, on compression of the coupling or adapter in its longitudinal direction, the engagement of the said tapered surfaces causes the said pipe engaging end to deform into sealing contact with a pipe.

10. A pipe coupling or flange adapter according to Claim 8 when dependent from Claim 2 wherein the clamp includes a further annular member that is spaced from the end ring in the longitudinal direction of the

coupling or adapter; at least one tightenable member interconnecting the end ring and the further annular member; and an annular body lying between the end ring and the further annular member, the annular body including a first tapered surface and the sealing member including adjacent its pipe engaging end a second tapered surface that is engageable with the first tapered surface such that in use, on compression of the coupling or adapter in its longitudinal direction, the engagement of the said tapered surfaces causes the said pipe engaging end to deform into sealing contact with a pipe.

11. A pipe coupling or flange adapter according to Claim 10 including a further, annular, elastomeric sealing member that is spaced from the first said sealing member in the longitudinal direction of the coupling or adapter, the annular body including a third tapered surface and the further sealing member including a fourth tapered surface that is engageable with the third tapered surface such that in use, on compression of the coupling or adapter in its longitudinal direction, the engagement of the said tapered surfaces causes the said pipe engaging end of the further sealing member to deform into sealing contact with a pipe.

12. A pipe coupling or flange adapter according to any of Claims 9 to 11 wherein the or each tightenable member is selectively tightenable to cause the said compression of the coupling or adapter.

13. A pipe coupling according to any preceding claim wherein the or each sealing ring includes a radially inner surface for engaging a pipe, the radially inner surface including one or more formations for enhancing its engagement with a said pipe.

14. A pipe coupling or flange adapter generally as herein described, with

reference to and/or as illustrated in the accompanying drawings.