WO2016063051A1

WO2016063051A1 - Improved sealing member for a pressure testing apparatus

Info

Publication number: WO2016063051A1
Application number: PCT/GB2015/053142
Authority: WO
Inventors: Ian Short
Original assignee: Ik-Uk Limited
Priority date: 2014-10-23
Filing date: 2015-10-21
Publication date: 2016-04-28
Also published as: GB201418845D0; GB2531579A

Abstract

The present invention relates to an elastomeric sealing member (1) for a pressure testing apparatus, the sealing member comprising a seal body (3) incorporating a plurality of reinforcement elements (13) embedded in the seal body adjacent a sealing edge (9, 11). The invention also relates to an anchoring apparatus incorporating the elastomeric sealing member of the invention and a method of making such a seal.

Description

IMPROVED SEALING MEMBER FOR A PRESSURE TESTING APPARATUS

The present invention relates to an improved sealing member for a pressure testing apparatus which apparatus is operable to enable pressure testing in pipes and other conduits intended to carry high pressure fluid. More specifically, though not exclusively, the invention relates to an elastomeric sealing member for a pressure testing apparatus deployable in pipes and other conduits intended to carry high pressure fluid such as hydrocarbons or the like, the sealing member incorporating a plurality of reinforcement elements.

Anchoring apparatus, such as pipe testing tools, adapted to be anchored in pipes for sealing pipes are known to enable pressure testing of sections of pipe. Pressure testing may be hydrostatic or may involve high pressure gas such as nitrogen for example. Currently, the pressure with which the test can be carried out using anchoring apparatus such as a flange weld tester, internal weld tester, high pressure pipe end plug or other similar anchoring apparatus for pipe testing is limited by the fluid force which can be applied to the anchoring apparatus and, more specifically, to the sealing member of the anchoring apparatus before the sealing member fails or the apparatus becomes jammed into the pipe under pressure testing. Typically, the sealing members used in pressure testing apparatus are formed of an elastomeric material such as polyurethane and the sealing member is activated, or energised, by applying an activation pressure to the sealing member, either mechanically or hydraulically, to form a fluid tight seal between the hub of the anchor apparatus and the internal diameter of the pipe under testing. Once the sealing member is energised, a test pressure from fluid under pressure may be applied to the pipe section under test. At pressures in excess of the threshold pressure for the sealing member, the material of the sealing member begins to extrude through the gap between anchor apparatus and the internal diameter of the pipe under testing. In such cases, the anchoring apparatus may become jammed into the pipe diameter or, in extreme cases, the sealing member may fail completely causing a catastrophic loss of seal from the anchoring apparatus. In either case, the anchor apparatus must be retrieved causing a downtime in the operation of the pipe and/or the apparatus. In certain applications, such as in the oil and gas industry for example, any downtime wherein fluid is not passing through the pipe is expensive and is to be avoided. An additional problem arises in providing anchoring apparatus for pipe testing which are able to be deployed in pipes and conduits having more than one internal diameter, or schedule. The internal diameter of a pipe may have variations in a single schedule such as weld beads or changes in ovality of the pipe schedule which the sealing member of the anchoring apparatus must accommodate in order to function correctly and under the required high pressure conditions. Typically, multiple tools need to be provided to accommodate each different pipe schedule.

Known sealing members for such anchoring apparatus used in pipe testing can typically operate at pressures from ambient to 230 bar. The present invention is predicated upon the inventor's realisation that pressure testing at high pressures, for example, up to 600 bar and beyond, would be highly beneficial in various operations such as in hydrocarbon pipe testing and the like.

It is an aim of the present invention to provide an elastomeric sealing member which mitigates some of the above referenced problems.

It is a further aim of the invention to provide an improved sealing member for a pressure testing apparatus which apparatus is operable to provide pressure testing in pipes and other conduits intended to carry high pressure fluid.

In a first aspect, the present invention provides an elastomeric sealing member for a pressure testing apparatus, the sealing member comprising a seal body incorporating a plurality of reinforcement elements embedded in the seal body adjacent a sealing edge.

It is much by preference that each of the plurality of reinforcement elements is substantially spherical. Most preferably each of the plurality of reinforcement elements is spherical. In this way, as force is applied to the material of the seal body the reinforcement elements are less prone to tearing or otherwise damaging the material of the seal body. Furthermore, a spherical reinforcement element provides crush resistance.

Each of the plurality of reinforcement elements may be partially embedded in the seal body.

In preferred embodiments, each of the plurality of reinforcement elements is wholly embedded in the seal body.

Each of the plurality of reinforcement elements may have a crush resistance of between 0.8 and 135 tonnes. More specifically, each spherical reinforcement element has a crush resistance of between about 5 tonnes and about 20 tonnes.

Each of the plurality of reinforcement elements is preferably solid.

Each of the plurality of reinforcement elements may be a ball bearing. More specifically, each reinforcement element may be a stainless steel ball bearing. Such material is resistant to rust formation and therefore is less likely to provide contaminant material to a fluid in the conduit under testing.

Alternatively, each of the plurality of reinforcement elements is a nylon bearing. Such material is resistant to rust and to high pressures and temperatures.

Further alternative materials may include titanium, polytetrafluoroethylene (PTFE), or other inert crush resistant material in spherical form.

Each reinforcement element is most preferably a solid, spherical crush resistant element. The diameter of each of the plurality of reinforcement elements is larger than the gap between the internal pipe diameter of the pipe section to be tested and the pipe testing tool to be deployed in the pipe section. The seal body may be formed of an elastomeric material. More specifically, the seal body is a mouldable elastomeric material.

In certain embodiments, the elastomeric material is cast at a shore hardness on the Shore A scale of between 55 and 95 shore hardness. In certain embodiments, the seal body is approximately 85 shore hardness on the Shore A scale.

The seal body may be polyurethane. More specifically, the polyurethane is cast at a shore hardness on the Shore A scale of between 55 and 95 shore hardness. In certain embodiments, the polyurethane seal body is approximately 85 shore hardness on the Shore A scale.

The seal body may be formed of silicone rubber, vulcanised rubber or the like.

The seal body is preferably generally ring-shaped. The seal body has an outer diameter and an inner bore. In use of the sealing member, a hub of an anchoring apparatus substantially fills the inner bore of the sealing member.

The outer diameter of the seal body forms the sealing engagement with the internal diameter of the pipe to be sealed.

The seal body preferably comprises first and second sealing surfaces. More specifically, the first sealing surface is an inner surface of the ring-shaped seal body. Even more specifically, the first sealing surface is operable to form a sealing engagement with the surface of the hub of an anchoring apparatus. The second sealing surface is an outer surface of the seal body. Even more specifically, the second sealing surface is operable to form a sealing engagement with the inner diameter of a pipe. The second sealing surface of the sealing member may comprise ridges. The ridges may form a corrugated outer surface of the sealing member. More specifically, the corrugated surface forms a sealing engagement with the internal diameter of a pipe in use of the elastomeric seal. The seal body preferably comprises a leading edge and a trailing edge. More specifically, the leading edge and the trailing edge of the seal body are the end edges located between the outer and the inner surfaces of the seal body and opposing ends thereof. The leading edge is operable to form a sealing engagement with the hub of an anchor apparatus. The hub of the anchoring apparatus will provide longitudinal resistance to the seal body during activation of the sealing member. In this way, radial expansion of the seal body is caused during activation of the sealing member so as to set the seal in the pipe internal diameter.

The trailing edge is operable to form a sealing engagement with the seal expander of an anchoring apparatus. More specifically, the seal expander will act upon the trailing edge of the seal body during activation of the sealing member. As the seal expander acts upon the trailing edge of the seal body and the leading edge of the seal body is prevented from further longitudinal movement by the hub of the anchoring apparatus, radial expansion of the seal body is caused so as to set the seal in the internal diameter of the pipe.

In certain embodiments, the leading edge is the sealing edge of the seal body.

Alternatively, the trailing edge is the sealing edge of the seal body. It is much by preference that the plurality of reinforcement elements are embedded in the seal body at the sealing edge around the circumference of the seal body. More specifically, the plurality of reinforcement elements are interspaced about the circumference of the seal body at the sealing edge thereof. The plurality of reinforcement elements may be spaced apart in uniform spacing around the circumference of the seal body. Alternatively, the plurality of reinforcement elements may each be touching two adjacent reinforcement elements. In such arrangements the plurality of reinforcement elements encircle the seal body about its entire circumference.

The plurality of reinforcement elements preferably form a reinforced ring section of the seal body at a sealing edge thereof.

The seal body may have a leading edge of substantially square cross-section.

In alternative embodiments, the seal body tapers in thickness towards its leading edge.

The seal body may have a trailing edge of substantially square cross-section.

In alternative embodiments, the seal body may taper in thickness towards its trailing edge.

The seal body may taper in thickness towards its leading and its trailing edge.

The taper reduces the thickness of the seal body towards its leading edge and/or its trailing edge.

The embedded reinforcement elements allow the elastomeric material of the seal body to expand during the energising of the seal. In this way, the sealing member of the present invention is operable to form a seal against multiple pipe schedules. In certain embodiments, the seal body is inflatable. Inflating the seal body in such embodiments energises the seal. Deflation of the seal body de-energises the seal. An inflatable seal body allows the sealing member to accommodate multiple schedules of pipe.

In certain embodiments, the seal body is energised by application of mechanical force. In such embodiments, it is preferred that the sealing edge of the sealing member is of square cross-section.

In certain embodiments, the seal body is energised by application of hydraulic force. In such embodiments, it is preferred that the sealing edge of the sealing member is of tapered cross-section. When the anchoring apparatus comprising the elastomeric sealing member is in position in the internal diameter of a pipe, the seal body is energised by applicable of an energising force to the seal. The seal body moves radially outwards relative to the longitudinal axis of the pipe bore and also longitudinally of the pipe until in sealing connection with the internal diameter of the pipe and the sealing surface of the hub of the anchoring apparatus. During energising of the seal body, the plurality of reinforcement elements are moved with the sealing edge of the seal body within which they are embedded into sealing engagement in the gap between the internal pipe diameter and the sealing edge of the hub of the anchoring apparatus. A pressure tight seal is thus formed. The presence of the reinforcement elements at the sealing edge of the sealing member prevents the material of the seal body being extruded through the gap between the anchoring apparatus carrying the sealing member and the internal diameter of the pipe. Instead, the reinforcement elements form a barrier to fluid flow through the gap and prevent further longitudinal movement of the sealing member. It is much by preference that the plurality of reinforcing members are located in the sealing edge of the seal body opposite the direction of fluid pressure application during use of the anchoring apparatus in a pressure test. During de-energising of the sealing member following the pipe test, the removal of seal activation pressure from the sealing member causing it to de-energise. It has been found that the plurality of reinforcement elements and the sealing edge of the sealing member undergo a snap deformation during energising and de-energising causing the sealing edge of the sealing member to seal and dissociate from the sealing engagement more quickly than previous sealing members.

In a second aspect the present invention provides an anchoring apparatus comprising a body, a seal expander and an elastomeric sealing member according to the first aspect of the present invention.

The elastomeric sealing member circumscribes the body of the apparatus at a sealing surface of the body portion.

The seal expander is positioned to be operable to energise the seal by urging same against the body of the apparatus causing radial expansion of the elastomeric sealing member outwardly of the apparatus relative to the longitudinal axis of the apparatus.

The anchoring apparatus may be a pipe weld tester. More specifically, the anchoring device may be a high pressure pipe end plug, an internal weld tester or a flange weld tester or the like.

The body of the apparatus may comprise a hub. The hub may be frustoconical in shape. The hub preferably provides a hub sealing surface providing for sealing engagement with the leading edge of the elastomeric sealing member. The seal expander is preferably C-shaped. The seal expander preferably provides a sealing surface providing for sealing engagement with the trailing edge of the elastomeric sealing member. In a third aspect, the present invention provides a method for forming an elastomeric seal according to the first aspect of the invention, the method comprising the steps of:- providing a ring-shaped mould having inner and outer opposing walls upstanding substantially perpendicularly from a base wall interconnecting the inner and outer opposing walls;

providing a plurality of reinforcement elements in the base of the mould, each of which plurality of reinforcement elements are touching two adjacent reinforcement elements around the circumference of the base of the mould; providing liquid or molten elastomer into the mould; and

- curing the elastomer in the mould.

It is much by preference that each of the plurality of reinforcement elements is substantially spherical. Most preferably each of the plurality of reinforcement elements is spherical.

The mould preferably comprises tapered inner and outer walls such that the outer diameter of the inner and outer walls is greater at the top than at the base of the mould. The diameter of the inner and outer walls of the mould may be approximately 2% greater at the top than at the base of the mould. A tapered mould results in an elastomeric sealing member of approximately uniform outer diameter due to the shrinkage of the elastomer during curing and the resistance to such shrinkage provided in the seal body in the area containing the spherical reinforcement elements.

The inner and outer walls of the mould are preferably uniformly spaced. In order that the invention be easily understood and readily carried into effect, reference will now be made, by way of example, to the accompanying drawings in which: - Figure la shows a schematic representation of a sealing member according to the invention;

Figure lb shows a cross section taken along line A-A of Figure la of the sealing member of Figure la;

Figure lc shows a cross section taken along line B-B of Figure la of the sealing member of Figure la;

Figures 2a and 2b show in longitudinal cross section of a pipe under pressure testing in which an anchoring apparatus in the form of an internal weld tester comprising an elastomeric sealing member according to the invention is deployed;

Figures 3a and 3b show in longitudinal cross section of a pipe under pressure testing in which an anchoring apparatus in the form of a pipe end plug comprising an elastomeric sealing member according to the invention is deployed;

Figure 4 shows a schematic representation of an elastomeric sealing member according to the invention; Figure 5 shows a schematic representation of a mould in which the elastomeric sealing member of Figure 4 is cast and cured;

Figure 6 shows a schematic representation of an alternative elastomeric sealing member according to the invention;

Figure 7 shows a schematic representation of an alternative mould in which the elastomeric sealing member of Figure 6 is cast and cured; and Figures 8a and 8b show in longitudinal cross section of a pipe under pressure testing in which an anchoring apparatus in the form of a pipe end plug comprising an alternative elastomeric sealing member according to the invention is deployed Throughout the Figures like features will be denoted by the same reference numerals. Similar features in alternative embodiments will be increased by an order of 100 throughout the Figures.

In pressure testing and isolation apparatus for use in pipes and other conduits it is necessary to provide both an anchoring apparatus in the form of a pipe end plug, flange weld tester or other similar anchoring apparatus and at least one seal to be energised. The anchoring apparatus may comprise one or more seals located so as to form a sealed connection between a surface of the anchoring apparatus and the inner diameter, or schedule, of the pipe section under test.

Figure la depicts an elastomeric sealing member 1 formed of polyurethane and having a corrugated outer sealing surface 5 and a generally ring-shaped cross section as best seen in Figure lc. Figure lb shows the cross section of the polyurethane sealing member 1 taken along section line A - A in Figure la. Figure lb shows sealing member 1 having a polyurethane seal body 3 comprising an outer sealing surface 5 having a corrugated or ridged surface profile and an inner sealing surface 7 which tapers in thickness of the sealed body 3 towards both leading sealing edge 9 and trailing sealing edge 11. In the depicted embodiment of Figures la to lc, a plurality of stainless steel ball bearings 13 are embedded entirely in the material of the sealed body 3 adjacent to the leading sealing edge 9 and contacting the seal body edges at both outer sealing surface 5 and inner sealing surface 7 internally of the seal body material 3. In alternative embodiments the seal body 3 may be formed of silicone rubber, vulcanised rubber or other similar elastomeric material. In further alternative arrangements the stainless steel ball bearings 13 may be replaced by a nylon bearing or other similar crush resistant material. In the depicted embodiment, ball bearing 13 is provided by a solid stainless steel bearing. As can be seen in Figure lc, a cross section of the sealing member 1 of Figure la taken along a sectional line B-B, the leading sealing edge 9 of seal body 3 contains a plurality of stainless steel ball bearings 13 embedded in the material of the seal body 3 around the entire circumference of the sealing member 1. Each ball bearing 13 within the ring of ball bearings 13 is in touching relation with two adjacent ball bearings 13 around the entire circumference of sealing member 1. In the depicted embodiment it can be seen that all of the ball bearings 13 are embedded entirely in the material of the sealed body 3, however in alternative arrangements it is envisaged that each ball bearing may be at least partially embedded in the material of the sealing member 1 at its sealing edge.

Figures 2 a and b show a longitudinal cross section of pipe under pressure testing in which an anchoring device, in the form an internal weld tester, (not shown in full) comprising an elastomeric sealing member 1 according to present invention is deployed. Figure 2a shows sealing member 1 in a de-energised state. Pipe 15 comprises an outer pipe diameter 17 and an inner pipe diameter 19. The anchoring apparatus in the form of a flange weld tester apparatus comprises a hub 21 in the form of a generally frustoconical shape and a seal expander 23 in generally C- shaped configuration whilst sealing member 1 is located between the lead face of seal expander 23 and a hub sealing edge 24. In order to energise seal member 1 into sealing engagement between the hub 21 and the pipe internal diameter 19, seal expander 23 is mechanically or hydraulically set against the trailing edge 11 of seal body 3 causing lateral force in the direction of arrow FL and a radial force in the direction of FR setting the seal body 3 into sealing engagement between the hub sealing edge 24 and the internal pipe diameter 19 thereby sealing the gap in the pipe therebetween.

In the energised seal, as best depicted in Figure 2b, the sealing edge 9 of sealing member 1 is adjacent to and in sealing engagement with the hub sealing edge 24 of hub 21. Ball bearings 13 are now locked in sealing engagement between the hub sealing edge 24 and the internal pipe diameter 19 so as to form a wall before the gap between the hub 21 and the internal pipe diameter 19. It can be seen that the ball bearings 13 are of greater diameter than the gap between the hub 21 and the internal pipe diameter 19 therefore preventing the sealing member 1 from extruding through the gap between the hub 21 and the internal pipe diameter 19. Fluid pressure in the direction of arrow Fp is then applied to the trailing edge 11 of sealing member 1 applying a lateral force in the direction of arrows FL against the ball bearingsl3 continuing to energise the sealing member 1. In Figure 2b the pressure is set against the sealing member 1 and the gap between the internal diameter 19 of the pipe 15 and the hub surface 24 are sealed against fluid ingress.

Once the pressure test of Figure 2b is complete, fluid pressure in the direction Fp can once again be removed and the sealing member will de-energise returning it to its de-energised state shown in Figure 2a It has been found that the presence of the ring of stainless steel ball bearings 13 in the sealing edge 9 of sealed body 3 acts in synergistic co-operation with the polyurethane material of the seal body 3 into which the ball bearings 13 are embedded and a snap deformation back to its de- energised state is observed once the fluid pressure and activation pressure is removed from the sealing member 1. Such a snap deformation from the energised to the de-energised state of sealing member 1 allows for a quicker removal of the pressure testing apparatus from the pipe or other conduit upon completion of the pressure test than has otherwise been seen with known devices.

Figures 3a and b show in longitudinal cross section a pipe 115 under pressure testing in which an anchoring apparatus in the form of a pipe end plug having a hub 121 and a seal expander 123 and comprising an elastomeric sealing member 101 according to the invention is deployed. Sealing member 101 comprises seal body 103, a leading sealing edge 109 and a trailing edge 111. Spherical reinforcement elements in the form of ball bearings 113 are embedded entirely in the sealed body 103 at its trailing sealing edge 111. During energising of seal member 111, seal expander 123 causes seal body 103 to move into sealing engagement with hub sealing edge 124. As can be seen in Figure 3b, once the pressure is set and the sealing member 101 is energised, the ring of ball bearings 113 in sealed body 103 at trailing edge 111 forms a barrier to fluid egress in the direction of arrow Fp through the gap between seal expander 123 and internal pipe diameter 115. Once again when sealing member 101 is de-energised the sealing member 101 returns to the position shown in Figure 3a such that the apparatus can be removed from the pipe 115 swiftly and with ease.

Figure 4 shows a schematic representation of a polyurethane sealing member 1 according to the invention. Sealing member 1 has a ring of stainless steel ball bearings 13 embedded in the polyurethane material of the sealing member 1 at a leading sealing edge 9. The outer diameter of the ring shaped elastomeric sealing member 1 tapers from its leading sealing edge 9 to its trailing sealing edge 11 such that the trailing sealing edge 11 is of lesser outer diameter than leading ceiling edge 9. The presence of the ring of reinforcing ball bearing members 13 in the leading trailing edge 9 of sealing member 1 lessens the shrinkage seen in the material of the elastomeric sealing member 1 during curing thereof such that the outer diameter of the sealed body 3 at its leading edge 9 is greater than the outer diameter of the trailing edge 11 where shrinkage of the curing material is greater due to the absence of the reinforcing spherical members. Figure 5 shows a mould comprising a ring of spherical solid ball bearings 13. Liquid polyurethane may be poured into the mould onto the ring of ball bearings 13 and allowed to cure in the square sided mould so as to form the sealing member 1 depicted in Figure 4. Each ball bearing 13 may have a crush load capability of 5 tonnes and may be formed of solid stainless steel. An elastomeric sealing member formed from such a mould may be moulded from polyurethane so as to have an outer diameter of 247mm, and a polyurethane shore hardness of 85 shore hardness on the Shore A scale and each ball bearing has a diameter of 10mm. Each ball bearing within mould 20 may be placed in touching arrangement with two adjacent ball bearings. The adjacent ball bearings are each free to rotate in position in the mould. Liquid polyurethane maybe poured into the aluminium mould 20 and allowed to cure so as to form sealing member 1. Such an elastomeric sealing member would be suitable for use in a pipe having an internal diameter of 258mm and an ovality to 254mm, for example. Fluid pressures of approximately 626 bar have been resisted by such an elastomeric sealing member wherein the gap between the anchoring apparatus and the internal diameter of the pipe is 5.5mm at each side of the apparatus.

Figure 6 shows a square sided sealing member 101 in which a ring of solid nylon bearings 113 is located at a leading sealing edge 109. It should be understood that nylon bearings 113 may be replaced by stainless steel bearings 13 of the embodiment depicted in Figure 4. The depicted sealing member 101 comprises of seal body 103 having a uniform outer diameter. The uniform diameter of such a sealing member 101 provides the advantage that the sealing member and the anchoring apparatus to which the sealing member 101 is attached can easily go into a pipe of known internal diameter before activation. The disadvantage of the sealing member 1 of Figure 4 is that the oversize of the outer diameter at the leading edge 9 maybe problematic in placing the seal in the initial instance in de-energised form into a pipe having a specified internal diameter. Figure 7 shows a mould 120 comprising a ring of nylon bearings 113 arranged around the circumference of the base of the mould 120. Liquid polyurethane is poured into the aluminium mould 120 and allowed to cure so as to embed solid spherical nylon bearings 113 into the polyurethane as it cures. Mould 120 has a tapered wall 122 so as to provide a lesser outer diameter at its base than at its upper edge. As the polyurethane poured into mould 120 cures the spherical reinforcement elements 113 resist shrinkage of the polyurethane at that area of the moulded sealing element 101 whereas the polyurethane of the seal body at the upper portion of mould 120 shrinks in accordance with its usual curing properties thus providing a sealing member 101 according to Figure 6 with a uniform outer diameter.

Due to the nature of the reinforced sealing member of the present invention, greater sealing force can be applied to the sealing member during setting of the seal and therefore the seal is capable of multi-scheduling so as to form sealing engagement with a number of internal pipe diameters or schedules.

Figures 8a and 8b depict an alternative sealing member 201 having a seal body 203 and a leading edge 209. Trailing edge 211 of seal body 203 comprises a ring of spherical reinforcement elements 213 embedded into the polyurethane material of the seal body 203. In order to energise the sealing member, seal expander 223 applies a lateral force in the direction of arrow FL to push the sealing member 201 longitudinally of the pipe 215 and up the tapered hub sealing surface 224. Once the seal is set (Figure 8b), the outer sealing surface 205 of sealing member 201 is in sealing engagement with the internal diameter 219 of pipe 215 and each of the plurality of ball bearings 213 is located in the gap between the internal pipe diameter 219 and the outer surface of the seal expander 223. In this way, the material of the sealing edge 211 of the seal body 203 is prevented from extruding into the gap under the fluid pressure F_p applied to the face of the hub 221 of the anchoring apparatus.

Various modifications and improvements in the various features of the invention are envisaged without departing from the scope of the invention. For example the seal body may be formed of any suitable elastomeric material and the spherical reinforcement elements maybe formed of any suitable crush resistance spherical material.

The elastomeric sealing member of the invention may be used as the sealing member on a number of pressure testing devices. The elastomeric sealing device may be used in anchoring apparatus suitable for pipe section isolation, weld testing, flange weld testing pressure testing or the like.

The elastomeric sealing member may be energised to provide a seal allowing a pressure test or pipe section isolation on the internal diameter of a pipe.

Claims

An elastomeric sealing member for a pressure testing apparatus, the sealing member comprising a seal body incorporating a plurality of reinforcement elements embedded in the seal body adjacent a sealing edge.

An elastomeric sealing member according to claim 1, wherein each of the plurality of reinforcement elements is substantially spherical.

An elastomeric sealing member according to claim 1 or claim 2, wherein each of the plurality of reinforcement elements is spherical.

An elastomeric sealing member according to any preceding claims, wherein each of the plurality of reinforcement elements is at least partially embedded in the seal body.

An elastomeric sealing member according to claim 4, wherein each of the plurality of reinforcement elements is wholly embedded in the seal body.

An elastomeric sealing member according to any preceding claim, wherein each of the plurality of reinforcement elements has a crush resistance of between 0.8 and 135 tonnes.

An elastomeric sealing member according to any preceding claim, wherein each of the plurality of reinforcement elements is solid.

An elastomeric sealing member according to any preceding claim, wherein each of the plurality of reinforcement elements is a ball bearing.

An elastomeric sealing member according to any one of claims 1 to 7, wherein each of the plurality of reinforcement elements is a nylon bearing.

10. An elastomeric sealing member according to any preceding claim, wherein the diameter of each of the plurality of spherical reinforcement elements is larger than the gap between the internal pipe diameter of the pipe section to be tested and the pipe testing tool to be deployed in the pipe section.

11. An elastomeric sealing member according to any preceding claim, wherein the seal body is formed of an elastomeric material.

12. An elastomeric sealing member according to any preceding claim, wherein the seal body is polyurethane.

13. An elastomeric sealing member according to any one of claims 1 to 11, wherein the seal body is formed of silicone rubber or vulcanised rubber.

14. An elastomeric sealing member according to any preceding claim, wherein the seal body is generally ring-shaped.

15. An elastomeric sealing member according to any preceding claim, wherein the seal body is has an outer diameter and an inner bore.

16. An elastomeric sealing member according to claim 15, wherein the outer diameter of the seal body forms a sealing engagement with the internal diameter of a pipe to be sealed.

17. An elastomeric sealing member according to any preceding claim, wherein the seal body comprises first and second sealing surfaces.

18. An elastomeric sealing member according to claim 17, wherein the first sealing surface is an inner surface of the ring-shaped seal body.

19. An elastomeric sealing member according to claim 17 or claim 18, wherein the second sealing surface is an outer surface of the seal body.

20. An elastomeric sealing member according to any preceding claim, wherein the seal body comprises a leading edge and a trailing edge. 21. An elastomeric sealing member according to claim 20, wherein the leading edge is operable to form a sealing engagement with the hub of an anchor apparatus

22. An elastomeric sealing member according to claim 20 or claim 21, wherein the trailing edge is operable to form a sealing engagement with the seal expander of an anchor apparatus.

23. An elastomeric sealing member according to any one of claims 20 to 22, wherein the leading edge is the sealing edge of the seal body.

24. An elastomeric sealing member according to any one of claims 20 to 22, wherein the trailing edge is the sealing edge of the seal body.

25. An elastomeric sealing member according to any preceding claim, wherein plurality of reinforcement elements are embedded in the seal body at the sealing edge around the circumference of the seal body.

26. An elastomeric sealing member according to any preceding claim, wherein the plurality of reinforcement elements are interspaced about the circumference of the seal body at the sealing edge thereof.

27. An elastomeric sealing member according to any preceding claim, wherein the plurality of reinforcement elements are spaced apart in uniform spacing around the circumference of the seal body.

28. An elastomeric sealing member according to any one of claims 1 to 26, wherein each of the plurality of reinforcement elements is touching two adjacent spherical reinforcement elements.

29. An elastomeric sealing member according to claim 28, wherein plurality of reinforcement elements encircle the seal body about its entire circumference.

30. An elastomeric sealing member according to any preceding claim, wherein the plurality of reinforcement elements preferably form a reinforced ring section of the seal body at a sealing edge thereof.

31. An elastomeric sealing member according to any preceding claim, wherein the plurality of reinforcing members are located in the sealing edge of the seal body opposite the direction of fluid pressure application during use of an anchoring apparatus incorporating the sealing member.

32. An anchoring apparatus comprising a body, a seal expander and an elastomeric sealing member according to any one of claims 1 to 31.

33. An anchoring apparatus according to claim 32, in which the elastomeric sealing member circumscribes the body of the apparatus at a sealing surface of the body.

34. An anchoring apparatus according to claim 32 or claim 33, wherein the seal expander is positioned to be operable to energise the seal by urging same against the body of the apparatus causing radial expansion of the elastomeric sealing member outwardly of the apparatus relative to the longitudinal axis of the apparatus.

35. A method for forming an elastomeric seal according to any one of claims 1 to 31, the method comprising the steps of:- providing a ring-shaped mould having inner and outer opposing walls upstanding substantially perpendicularly from a base wall interconnecting the inner and outer opposing walls;

curing the elastomer in the mould.

36. A method according to claim 35, in which each of the plurality of reinforcement elements is substantially spherical.

37. A method according to claim 35 or claim 36, wherein the mould comprises tapered inner and outer walls such that the outer diameter of the inner and outer walls is greater at the top than at the base of the mould.