WO2019239114A1

WO2019239114A1 - Toothed rigid body for wire securement

Info

Publication number: WO2019239114A1
Application number: PCT/GB2019/051609
Authority: WO
Inventors: Richard Alasdair Clements
Original assignee: GE Oil and Gas UK Ltd
Current assignee: Baker Hughes Energy Technology UK Ltd
Priority date: 2018-06-13
Filing date: 2019-06-10
Publication date: 2019-12-19
Anticipated expiration: 2020-12-13
Also published as: GB201809676D0

Abstract

A method and apparatus for securing an end region of a tensile armour wire within a flexible pipe end fitting and a method of terminating flexible pipe body in an end fitting are disclosed. The apparatus comprises a rigid support body comprising at least one anchoring surface and including a slit between a first abutment surface of the support body and a further abutment surface of the support body that is spaced apart from the first abutment surface. Each abutment surface comprises a respective toothed region including teeth and a space between teeth of the first and further abutment surfaces is narrower at a root end of the slit proximate to a base region of the rigid support body than at an open mouth end of the slit distal to the base region. The space proximate to the base region comprises a region having a width that is equal to between 1.0 and 0.90 times a wire width of a tensile armour wire that has a width of between 2 and 10 mm.

Description

TOOTHED RIGID BODY FOR WIRE SECUREMENT

The present invention relates to a method and apparatus for helping secure ends of armour wire of a flexible pipe within an end fitting. In particular, but not exclusively, the present invention relates to the addition of easy attaching securing elements on ends of tensile armour wires of a flexible pipe, prior to their submersion in epoxy resin, as part of a pipe body termination operation. Affixing a support body to the wire provides anchoring points that help prevent extraction of the wire from the epoxy region during later use of the flexible pipe. Using a rigid support body that includes toothed regions lets wire be positioned easily onto the support body but prevents backwards motion of the wire once the support body is at a desired location.

Traditionally flexible pipe is utilised to transport production fluids, such as oil and/or gas and/or water, from one location to another. Flexible pipe is particularly useful in connecting a sub-sea location (which may be deep underwater, say 1000 metres or more) to a sea level location. The pipe may have an internal diameter of typically up to around 0.6 metres (e.g. diameters may range from 0.05 m up to 0.6 m). A flexible pipe is generally formed as an assembly of flexible pipe body and one or more end fittings. The pipe body is typically formed as a combination of layered materials that form a pressure-containing conduit. The pipe structure allows large deflections without causing bending stresses that impair the pipe’s functionality over its lifetime. There are different types of flexible pipe such as unbonded flexible pipe which is manufactured in accordance with API 17J or composite type flexible pipe or the like. The pipe body is generally built up as a combined structure including polymer layers and/or composite layers and/or metallic layers. For example, pipe body may include polymer and metal layers, or polymer and composite layers, or polymer, metal and composite layers. Layers may be formed from a single piece such as an extruded tube or by helically winding one or more wires at a desired pitch or by connecting together multiple discrete hoops that are arranged concentrically side-by-side. Depending upon the layers of the flexible pipe used and the type of flexible pipe some of the pipe layers may be bonded together or remain unbonded.

Some flexible pipe has been used for deep water (less than 3,300 feet (1 ,005.84 metres)) and ultra-deep water (greater than 3,300 feet) developments. It is the increasing demand for oil which is causing exploration to occur at greater and greater depths (for example in excess of 8202 feet (2500 metres)) where environmental factors are more extreme. For example in such deep and ultra-deep water environments ocean floor temperature increases the risk of production fluids cooling to a temperature that may lead to pipe blockage. In practice flexible pipe conventionally is designed to perform at operating temperatures of -30°C to +130°C, and is being developed for even more extreme temperatures. Increased depths also increase the pressure associated with the environment in which the flexible pipe must operate. For example, a flexible pipe may be required to operate with external pressures ranging from 0.1 MPa to 30 MPa acting on the pipe. Equally, transporting oil, gas or water may well give rise to high pressures acting on the flexible pipe from within, for example with internal pressures ranging from zero to 140 MPa from bore fluid acting on the pipe. As a result the need for high levels of performance from certain layers such as a pipe carcass or a pressure armour or a tensile armour layer of the flexible pipe body is increased. It is noted for the sake of completeness that flexible pipe may also be used for shallow water applications (for example less than around 500 metres depth) or even for shore (overland) applications.

When flexible pipe body is terminated at each end with an end fitting it is known that the various layers within the flexible pipe body must be separately cut and sealed as part of a termination process. Conventionally tensile armour wires which are wires helically wound along a length of the flexible pipe body are terminated in a complicated and therefore costly manner. Typically each tensile armour wire (there may be up to a hundred or more) must be bent away from a bore region of the flexible pipe body without overbending and then each armour wire must be cut to an appropriate length. The bending is required to access the ends of all of the tensile armour wires in the flexible pipe body to apply a crimp which thereafter helps anchor and thereby secure the wires in the end fitting. The bending back operation is dangerous as the wires splay around 360 degrees in a plane perpendicular to an axis of the pipe. The crimping of the wires is also potentially damaging to the wires as it requires very high levels of local deformation. Some methods of crimping may also attempt to stretch the wire which may sometimes result in wire breakage. Furthermore, a containment space (a volume) required for the crimped wires in the end fitting void space (which is later filled with a curable material such as an epoxy potting compound or the like) is also fairly large due to the build-up of space required with all adjacent and overlying crimped wires around the body of the end fitting. This results in a larger and thus heavier termination end fitting body being required which thereafter is difficult to handle.

After bending, the ends of the tensile armour wires are conventionally fixed in place with respect to the remainder of the end fitting by locating the crimped tensile armour wire ends in a void space within the end fitting which is filled with epoxy resin as part of the termination process. As the curable epoxy solidifies the armour wire ends are interred within the epoxy material. Often this results in an adequate securing mechanism for securing end regions of tensile armour wire within an end fitting. However, as noted above, the process is time consuming, can be dangerous, is costly and furthermore is occasionally prone to tensile armour wires, which are under significant tensile stress in use, pulling free from the epoxy. This is because conventionally the epoxy only acts for frictional purposes against an outer (generally smooth) surface of any tensile wire.

It is an aim of the present invention to at least partly mitigate at least one of the above- mentioned problems.

It is an aim of certain embodiments of the present invention to help increase an extraction force needed to extract each and every (or at least some) tensile armour wire from an epoxied region within an end fitting.

It is an aim of certain embodiments of the present invention to help provide a mechanism whereby extraction of tensile armour wires from a desired position within an end fitting can be avoided wholly or at least partially.

It is an aim of certain embodiments of the present invention to provide an anchoring mechanism for helping to secure an end region of a tensile armour wire within an end fitting/termination in a manner which is cost effective and which is efficient for human operators involved in an end fitting operation to carry out and which results in an effective anchoring effect to secure wires in a desired location.

According to a first aspect of the present invention there is provided apparatus for securing an end region of a tensile armour wire within a flexible pipe end fitting, comprising:

a rigid support body comprising at least one anchoring surface and including a slit between a first abutment surface of the support body and a further abutment surface of the support body that is spaced apart from the first abutment surface; wherein

each abutment surface comprises a respective toothed region including teeth and a space between teeth of the first and further abutment surfaces is narrower at a root end of the slit proximate to a base region of the rigid support body than at an open mouth end of the slit distal to the base region, said space proximate to the base region comprising a region having a width that is equal to between 1 .0 and 0.90 times a wire width of a tensile armour wire that has a width of between 2 and 10 mm. Aptly the apparatus further comprises each toothed region comprises a plurality of teeth having an asymmetrical saw tooth profile including a long edge and a short edge, said long edge extending at an angle of less than 45° to a imaginary centre line of the slit, and said short edge extending at an angle of greater than 45° to the imaginary centre line.

Aptly the apparatus further comprises the configuration of the teeth of the toothed region of the first abutment surface is a mirror image of the configuration of the teeth of the toothed region of the further abutment surface.

Aptly the apparatus further comprises an apex line associated with a location of an apex point along a length of each tooth as it extends through a thickness of the support body is non-orthogonal to a plane of the base region of the support body.

Aptly the apparatus further comprises the space distal to the base region comprises a region having a continually increasing width up to the open mouth of the slit.

Aptly the apparatus further comprises a cover member locatable over a surface of the rigid support body distal to the base region to cover the slit.

Aptly the apparatus further comprises the rigid support body and cover member each comprise cooperating securing elements to enable the cover to be permanently or releasably secured to the rigid support body.

Aptly the apparatus further comprises the cover member comprises at least one rib having a width that is locatable in the open mouth of the slit and that has a predetermined depth for locating an abutment end of the rib at a depth in the slit proximate to a side of a tensile wire located in the slit proximate to the base region.

Aptly the the rigid support body has a hardness greater than 12 HRc.

Aptly the hardness is greater than 30 HRc and optionally is greater than 40 HRc.

Aptly the apparatus further comprises the rigid support body is securable to a free end region of a tensile armour wire so strongly that the wire breaks under tensile loading before the rigid support body pulls from the wire. According to a second aspect of the present invention there is proviced a method of securing an end region of at least one flexible pipe body tensile armour wire to an anchoring element, comprising the steps of:

urging a free end region of a tensile armour wire into a slit in a rigid support body that comprises at least one anchoring surface and, as the tensile armour wire is urged in the slit, providing a bite on sides of the tensile armour wire by opposed teeth on toothed regions of respective first and further abutment surfaces of the support body; and

subsequently preventing movement of the rigid support body with respect to the tensile armour wire in a direction towards a free end of the tensile armour wire via the teeth in the toothed regions.

Aptly the method further comprises urging the free end region by locating the tensile armour wire over the slit and pushing the tensile armour wire into the slit at a desired location a predetermined distance from the free end.

According to a third aspect of the present invention there is provided a method of terminating flexible pipe body in an end fitting, comprising the steps of:

providing an end fitting body comprising a connecting flange at a first end fitting end and an open mouth at a further end fitting end;

urging a free end region of each tensile armour wire of a plurality of tensile armour wires, into a slit in a rigid support body that comprises at least one anchoring surface, between teeth of toothed regions of opposed abutment surfaces of the rigid support body; subsequently preventing withdrawal of the tensile armour wire from the slit via teeth of the toothed regions which oppose movement of the rigid support body in a direction towards a free end of the tensile armour wire;

securing a jacket member to the end fitting body thereby providing a cavity void region in the end fitting where respective end regions of the plurality of tensile armour wires and associated rigid housings and respective anchoring surfaces are located; and

subsequently providing a curable material in the cavity void region.

Aptly the method further comprises locating a cover member that includes a rib over an open mouth end of the slit and securing the cover member to the rigid support body. Aptly the method further comprises as the cover is secured to the rigid support body, locating an abutment end of the rib proximate to a side of a tensile armour wire located in the slit proximate to a root end of the slit.

Aptly the method further comprises applying a load to the tensile armour wire of at least 50% of the structural capacity of the tensile armour wire to thereby confirm that the rigid support body and associated anchoring surface is secured at a desired location.

Aptly the method further comprises subsequently curing the material and thereby anchoring the tensile armour wire end regions in the cured material in the cavity void region via the rigid support bodies on each tensile armour wire end region.

Certain embodiments of the present invention provide a cost effective solution for securing ends of tensile armour wire in an epoxied region within an end fitting. Securing bodies which can be threaded over each wire are provided and each of these helps anchor a respective wire in position and can be readily utilised by an operator.

Certain embodiments of the present invention provide securing bodies which are cheap to manufacture and which are easy to use as anchoring points.

Certain embodiments of the present invention provide a mechanism by which one or more rigid support elements can be fixed on a tensile armour wire to increase its effective cross- section at specific locations along its length. The anchoring mechanism may be provided as rigid support elements secured on each wire with at least one abutment surface that includes a toothed region that automatically energises into an operative state when an attempt is made to withdraw a tensile armour wire, whereby removal of a support element from an outer surface of a tensile armour wire is restricted once the support is located at a desired location.

Certain embodiments of the present invention provide for the application of slit bodies onto tensile armour wires. Each of the slit bodies can be attached onto a free end of a respective tensile armour wire and a toothed region in the body accommodate a tensile wire and allow a support to be mounted onto a wire but also to stop the wire being subsequently withdrawn off the support. This helps provide an easier and quicker and safer anchoring operation to help secure a tensile armour wire in an end fitting than is currently available with conventional techniques. Certain embodiments of the present invention provide securing element bodies in the forms of slit bodies which can slide onto wires at a set distance from a wire end.

Certain embodiments of the present invention will now be described hereinafter, by way of example only, with reference to the accompanying drawings in which:

Figure 1 illustrates flexible pipe body;

Figure 2 illustrates certain uses of a flexible pipe;

Figure 3 helps illustrate an end of a flexible pipe where flexible pipe body is terminated in an end fitting;

Figure 4 illustrates a rigid support body that is slit and positioned onto a tensile armour wire;

Figure 5 illustrates a plan view of a support body showing a central slit with toothed side walls;

Figure 6 illustrates a toothed side wall with backward facing teeth;

Figure 7 illustrates a rigid housing being mounted on an end region of a tensile wire and then a lid being sealed in place;

Figure 8 illustrates a support body on a tensile armour wire; and

Figure 9 illustrates an alternative rigid housing that can accommodates ends of multiple (two shown) armour wires.

In the drawings like reference numerals refer to like parts.

Throughout this description, reference will be made to a flexible pipe. It is to be appreciated that certain embodiments of the present invention are applicable to use with a wide variety of flexible pipe. For example certain embodiments of the present invention can be used with respect to flexible pipe and associated end fittings of the type which is manufactured according to API 17J. Such flexible pipe is often referred to as unbonded flexible pipe. Other embodiments are associated with other types of flexible pipe. Turning to Figure 1 it will be understood that the illustrated flexible pipe is an assembly of a portion of pipe body and one or more end fittings (not shown) in each of which a respective end of the pipe body is terminated. Figure 1 illustrates how pipe body 100 is formed from a combination of layered materials that form a pressure-containing conduit. As noted above although a number of particular layers are illustrated in Figure 1 , it is to be understood that certain embodiments of the present invention are broadly applicable to coaxial pipe body structures including two or more layers manufactured from a variety of possible materials. The pipe body may include one or more layers comprising composite materials, forming a tubular composite layer. It is to be further noted that the layer thicknesses are shown for illustrative purposes only. As used herein, the term“composite” is used to broadly refer to a material that is formed from two or more different materials, for example a material formed from a matrix material and reinforcement fibres.

A tubular composite layer is thus a layer having a generally tubular shape formed of composite material. Alternatively a tubular composite layer is a layer having a generally tubular shape formed from multiple components one or more of which is formed of a composite material. The layer or any element of the composite layer may be manufactured via an extrusion, pultrusion or deposition process or, by a winding process in which adjacent windings of tape which themselves have a composite structure are consolidated together with adjacent windings. The composite material, regardless of manufacturing technique used, may optionally include a matrix or body of material having a first characteristic in which further elements having different physical characteristics are embedded. That is to say elongate fibres which are aligned to some extent or smaller fibres randomly orientated can be set into a main body or spheres or other regular or irregular shaped particles can be embedded in a matrix material, or a combination of more than one of the above. Aptly the matrix material is a thermoplastic material, aptly the thermoplastic material is polyethylene or polypropylene or nylon or PVC or PVDF or PFA or PEEK or PTFE or alloys of such materials with reinforcing fibres manufactured from one or more of glass, ceramic, basalt, carbon, carbon nanotubes, polyester, nylon, aramid, steel, nickel alloy, titanium alloy, aluminium alloy or the like or fillers manufactured from glass, ceramic, carbon, metals, buckminsterfullerenes, metal silicates, carbides, carbonates, oxides or the like.

The pipe body 100 illustrated in Figure 1 includes an internal pressure sheath 1 10 which acts as a fluid retaining layer and comprises a polymer layer that ensures internal fluid integrity. The layer provides a boundary for any conveyed fluid. It is to be understood that this layer may itself comprise a number of sub-layers. It will be appreciated that when a carcass layer 120 is utilised the internal pressure sheath is often referred to by those skilled in the art as a barrier layer. In operation without such a carcass (so-called smooth bore operation) the internal pressure sheath may be referred to as a liner. A barrier layer 1 10 is illustrated in Figure 1 .

It is noted that the carcass layer 120 is a pressure resistant layer that provides an interlocked construction that can be used as the innermost layer to prevent, totally or partially, collapse of the internal pressure sheath 110 due to pipe decompression, external pressure, and tensile armour pressure and mechanical crushing loads. The carcass is a crush resistant layer. It will be appreciated that certain embodiments of the present invention are thus applicable to‘rough bore’ applications (with a carcass). Aptly the carcass layer is a metallic layer. Aptly the carcass layer is formed from stainless steel, corrosion resistant nickel alloy or the like. Aptly the carcass layer is formed from a composite, polymer, or other material, or a combination of materials and components. A carcass layer is radially positioned within the barrier layer.

The pressure armour layer 130 is a pressure resistant layer that provides a structural layer that increases the resistance of the flexible pipe to internal and external pressure and mechanical crushing loads. The layer also structurally supports the internal pressure sheath. Aptly as illustrated in Figure 1 the pressure armour layer is formed as a tubular layer. Aptly for unbonded type flexible pipe the pressure armour layer consists of an interlocked construction of wires with a lay angle close to 90°. Aptly in this case the pressure armour layer is a metallic layer. Aptly the pressure armour layer is formed from carbon steel, aluminium alloy or the like. Aptly the pressure armour layer is formed from a pultruded composite interlocking layer. Aptly the pressure armour layer is formed from a composite formed by extrusion or pultrusion or deposition. A pressure armour layer is positioned radially outside an underlying barrier layer.

The flexible pipe body also includes a first tensile armour layer 140 and second tensile armour layer 150. Each tensile armour layer is used to sustain tensile loads and optionally also internal pressure. Aptly for some flexible pipes the tensile armour windings are metal (for example steel, stainless steel or titanium or the like). For some composite flexible pipes the tensile armour windings may be polymer composite tape windings (for example provided with either thermoplastic, for instance nylon, matrix composite or thermoset, for instance epoxy, matrix composite). For unbonded flexible pipe the tensile armour layer is formed from a plurality of wires. (To impart strength to the layer) that are located over an inner layer and are helically wound along the length of the pipe at a lay angle typically between about 10° to 55°. Aptly the tensile armour layers are counter-wound in pairs. Aptly the tensile armour layers are metallic layers. Aptly the tensile armour layers are formed from carbon steel, stainless steel, titanium alloy, aluminium alloy or the like. Aptly the tensile armour layers are formed from a composite, polymer, or other material, or a combination of materials.

Aptly the flexible pipe body includes optional layers of tape 160 which help contain underlying layers and to some extent prevent abrasion between adjacent layers. The tape layer may optionally be a polymer or composite or a combination of materials, also optionally comprising a tubular composite layer. Tape layers can be used to help prevent metal-to- metal contact to help prevent wear. Tape layers over tensile armours can also help prevent “birdcaging”.

The flexible pipe body also includes optional layers of insulation 165 and an outer sheath 170, which comprises a polymer layer used to protect the pipe against penetration of seawater and other external environments, corrosion, abrasion and mechanical damage. Any thermal insulation layer helps limit heat loss through the pipe wall to the surrounding environment.

Each flexible pipe comprises at least one portion, referred to as a segment or section, of pipe body 100 together with an end fitting located at at least one end of the flexible pipe. An end fitting provides a mechanical device which forms the transition between the flexible pipe body and a connector. The different pipe layers as shown, for example, in Figure 1 are terminated in the end fitting in such a way as to transfer the load between the flexible pipe and the connector.

Figure 2 illustrates a riser assembly 200 suitable for transporting production fluid such as oil and/or gas and/or water from a sub-sea location 221 to a floating facility 222. For example, in Figure 2 the sub-sea location 221 includes a sub-sea flow line 225. The flexible flow line 225 comprises a flexible pipe, wholly or in part, resting on the sea floor 230 or buried below the sea floor and used in a static application. The floating facility may be provided by a platform and/or buoy or, as illustrated in Figure 2, a ship. The riser assembly 200 is provided as a flexible riser, that is to say a flexible pipe 240 connecting the ship to the sea floor installation. The flexible pipe may be in segments of flexible pipe body with connecting end fittings. It will be appreciated that there are different types of riser, as is well-known by those skilled in the art. Certain embodiments of the present invention may be used with any type of riser, such as a freely suspended (free-hanging, catenary riser), a riser restrained to some extent (buoys, chains), totally restrained riser or enclosed in a tube (I or J tubes). Some, though not all, examples of such configurations can be found in API 17J. Figure 2 also illustrates how portions of flexible pipe can be utilised as a jumper 250.

Figure 3 helps illustrate how a respective end of a segment of flexible pipe body 100 can be terminated in an end fitting 300. The end fitting 300 includes a main end fitting body 310 which includes a flanged end 315 which acts as a connector for securing to another end fitting in a back-to-back relationship or to a rigid structure. A narrow neck 320 extends into a central flared out region 330. The end fitting 300 includes an end fitting body 310 which defines an internal bore 335 running along a length of the end fitting body. This bore has a diameter to match a corresponding bore of the flexible pipe body. The end fitting body is made from steel or some other such rigid material. The flanged end region 315 provides a connector at a first end of the end fitting body. The other end of the end fitting body defines an open mouth 340 into which an end of a segment of flexible pipe body is received. The flanged connector is a substantially disc-like flared region of the end fitting body. The connector can be connected directly to a matching connector or a further end fitting body of an adjacent segment of flexible pipe body. This can be done using bolts or some other form of securing mechanism. Alternatively the connector 315 may be connected to a floating or stationery structure such as a ship, platform or the like. Various layers of flexible pipe body are introduced to the end fitting assembly, cut to an appropriate length, and sealingly engaged with a particular portion of the end fitting.

As illustrated in Figure 3 the end fitting 300 also includes a jacket 350 which is secured at a first end of the jacket to the central flanged region of the end fitting body. The jacket has a substantially cylindrical outer surface. A remaining end of the jacket 350 is secured to an end plate 355. A radially inner surface 360 of the jacket remains spaced apart from a radially outer surface 365 of the open mouth end of the end fitting body 310 and a radially outer surface 370 of an inner collar 375. An outer sleeve 380 helps urge an outer sheath 170 against an outer seal 385. The spaced apart relationship of the inner surface 360 of the jacket and radially outer surfaces of the end fitting body and inner collar define a pocket region 390 or cavity void into which tensile armour wires 395 of the first tensile armour layer 140 and second tensile armour layer 150 are terminated. As part of a terminating process the cavity void in the pocket region 390 is filled with a curable material subsequent to the jacket being secured to the end fitting body. The curable material, such as epoxy resin, or the like solidifies to inter the individual tensile armour wires 395 in the pocket region. As illustrated in Figure 3 securing housings anchoring apparatus 398 are secured to end regions of the tensile armour wires at a predetermined distance from a tip of each wire to help anchor the tensile armour wires in the curable material. This helps increase resistance to the tensile armour wires being pulled through the epoxy material. This increases an extraction force needed to extract the wires.

Figure 4 helps illustrate an end region 400 of a particular tensile armour wire 395 in more detail. The tensile armour wire 395 shown in Figure 4 has a generally rectangular cross section with substantially parallel spaced apart long edges spaced apart by shorter edges. The shorter edges illustrated in the tensile armour wire shown in Figure 4 are slightly curved whereas the longer edges define substantially flat upper and lower surfaces for the tensile armour wires. It will be appreciated that certain embodiments of the present invention are broadly applicable to tensile armour wires and their anchoring having a wide selection of possible cross sections. Multiple helically wound tensile armour wires make up the inner and outer tensile armour layers of the flexible pipe body.

Figure 4 helps illustrate a free end 450 of a respective tensile armour wire and how this can be urged into a slit 460 in a support body 460 of the anchoring apparatus 398. The securing element body 460 can be positioned along the outer surface of a tensile armour wire at a predetermined distance from the wire tip 450. Aptly this is 5cm. Aptly this is between 5 and 25cm. Aptly this is between 4 and 15cm from the wire end.

As shown in Figure 4 a free end region 400 of a tensile armour wire 395 close to the free end 450 can be slid into a slit in a rigid support body. The rigid support body 450 illustrated in Figure 4 is provided by securing a first body portion 462 (on the left hand side in Figure 4) and a further body side portion 464 to a base 466. Optionally as an alternative the body 460 could be integrally formed. The side body portion 462 and further side body portion 464 are secured to the base 466 via bolts or other such securing mechanisms. Optionally as an alternative the side body parts can be welded to the base.

The side body portions have ends which respectively are spaced apart and align with ends of the overall rigid support body and spaced apart side walls. An inner facing side wall 470 of the first side body portion 462 provides an abutment surface on the inside of the slit that runs through the support body. This abutment surface is a toothed region. In the embodiment shown in Figure 4 the entire abutment surface is toothed and includes teeth along its whole length. It will be appreciated that as an alternative only a part of the inner abutment surface may include teeth. Likewise an inner surface 475 of the right hand side (in Figure 4) side body portion of the rigid support body 460 provides an abutment surface and defines a side of the slit that runs through the rigid support body. This likewise includes a respective toothed region including teeth. In the embodiment shown in Figure 4 the whole of the inner abutment surface of the right hand side side portion of the support body is a toothed region. In this way the rigid support body 460 includes outer surfaces which provide at least once anchoring surface which is greater in cross section than a cross section otherwise provided by a tensile armour wire. The rigid support body 460 includes a slit 460 which runs through the length of the body and the slit is defined between a first abutment surface of the support body and a further abutment surface of the support body. The two abutment surfaces are spaced apart by a distance. Each abutment surface comprises a respective toothed region including teeth and a space between teeth of the first and further abutment surfaces is narrower at a root end of the slit proximate to a base region of the rigid support body than at an open mouth end of the slit distal to the base region. That is to say near the base 466 at the bottom (in Figure 4) of the support body the slit is narrower than towards the top (in Figure 4) of the slit. The space near the base provides a region having a width that is equal to between 1 .0 and 0.90 times a width w of a tensile armour wire. Aptly the tensile armour wire has a width of between 2 and 10mm. Aptly the width is between 3 and 8mm. A tensile armour wire free end region 400 can thus be urged into the slot by a human operator through the open mouth of the slit. This can locate the free end 450 sticking out of the slit or alternatively could put the free end within the slit itself. The upper surface of the side body portions include securing elements 490. These are shown as threaded holes in Figure 4. Their purpose is described later.

Each toothed region includes a plurality of teeth which have an asymmetric saw tooth profile. Figure 5 helps illustrate the asymmetrical saw tooth profile looking from the top of the slit shown in Figure 4. Each tooth includes a long edge 500 and a short edge 510. The long edge extends at an angle of less than 45 degrees to an imaginary centre line shown by the line A-A in Figure 5 of the slit. The short edges of each tooth extend at an angle of greater than 45 degrees to the imaginary centre line. The teeth of the toothed region of the first abutment surface 470 on the left hand side of the rigid support body is a mirror image of the configuration of the teeth of the toothed region of the further abutment surface 475 which is provided by the right hand side (in Figure 4) side portion of the rigid support body 460. Figure 6 helps illustrate how an apex line 600 associated with a location of an apex point along a length of each tooth as it extends through a thickness of the support body is non- orthogonal to a plane of the base region of the support body. That is to say the sharp edges of the teeth do not extend vertically upward from the base. This angle helps prevent a tensile armour wire from being withdrawn from the slit once duly located. A deep recess line 610 shows where the teeth are most recessed in the support body.

Figure 7 helps illustrate how a tensile armour wire 395 can be slid into the slit by a human operator. Figure 7A helps illustrate how the first side portion 462 of the rigid support body 460 is secured to the base 466 and how the respective abutment surface 470 is spaced apart from a corresponding abutment surface 475 provided by a surface of a side of the further side portion 464 of the rigid support body. Figure 7A helps illustrate how a root end of the slit (that is to say an end of the slit close to the base of the rigid support body) is spaced apart less than a corresponding space at an open mouth or open part of the slit. This helps enable the tensile armour wire to be introduced into the slit by a human operator at a desired location. The angle of the abutment surfaces with respect to the base is very small. That is to say the angle of the teeth is close to being orthogonal to the base. Aptly the angle is between 89.5 degrees and 80 degrees. Optionally part of the space may have a common width. That is to say a taper does not extend all the way through the width of the slit. The taper can be stepped or smooth.

Figure 7B illustrates how a cover 700 is locatable over a surface on the upper side of the rigid support body. This upper surface 710 is spaced apart from the base region of the rigid support body. The cover is a member which can cover the open mouth of the slit to secure the tensile armour wire in the support body. As illustrated in Figure 7B and Figure 7C the cover member can optionally include a rib 720 which extends below the level of the surface 710 into the slit. In the embodiment shown in Figure 7 the rib extends a whole length along the rigid support body to fill the slit. Optionally each rib may only have a partial length with respect to an entire length of the slit. An abutment end 730 is at an extreme end of the rib. The rib thus has a width that is locatable in the open mouth of the slit and also has a predetermined depth for locating the abutment end of the rib at a depth in the slit close to or in contact with an upper side of a tensile armour wire which is previously located in the slit proximate to the base region.

Figure 7C helps illustrate how bolts 750 can be used to secure the cover to the upper surface of the side portions of the rigid support body. The bolts 750 pass through respective openings 760 in the cover and secure into threaded openings 490 in the side portions of the rigid body.

In use due to the mass and thus weight of the flexible pipe, tensile armour wires can tend to pull out of an end fitting with significant force. To be able to resist such force the captive element and the rigid housing must be sufficiently hard and rigid so as to be able to sustain continued load throughout the lifetime of a flexible pipe. Aptly a hardness of the rigid housing and/or a hardness of a captive element has a hardness greater than 12HRc. Aptly the hardness is greater than 30HRc. Aptly the hardness is greater than 40HRc.

Figure 8 illustrates how a rigid support body 460 can be secured at an end of an tensile armour wire in more detail. It will be appreciated that the external surfaces and particularly the end surfaces of the rigid housing close to the inlet opening provide anchoring points when the tensile armour wires are sealed/entombed in epoxy in a space within the end fitting. The surfaces thus provide a greater surface area than the tensile armour wire would otherwise provide alone which resists any movement of the housing once entombed in the hard epoxy. It will be appreciated that Figures 4 and 8 do not show a cover of the anchoring apparatus for the sake of clarity but that in practice the cover closes the tensile wire in the slit to further confine the wire during a termination process. Only six tensile armour wires are illustrated in Figure 5 for the sake of clarity. The skilled person will understand many more than six wires can be used to provide a tensile layer.

The rigid support body and cover that provide anchoring apparatus 460 can thus be used to enable an end region of at least one flexible pipe body tensile armour wire to be secured to an anchoring element. A rigid support body behaves as an anchoring element as it provides surfaces which act as an anchor to resist motion of the entire housing through hardened epoxy when a tensile armour wire tends to pull from an end fitting. The method of securing an end region of the wire to the anchoring element includes an operator first securing a rigid support body on an end of each tensile armour wire of flexible pipe body which is to be terminated in an end fitting. Each tensile armour wire free end region is urged into a respective slit in a rigid support body that itself provides one or more anchoring surfaces. More than one rigid support body and associated cover could of course be used on each wire to increase an anchoring strength. As the tensile armour wire is urged into the slit through an open mouth of the slit teeth on the side walls bite on the outer surface of the wire to help prevent movement. Once the tensile armour wires each have a rigid support body mounted on them a desired distance from a free end of the wire. The end fitting termination process can continue using conventional techniques.

Figure 9 illustrates an alternative embodiment of the present invention in which a rigid support body includes a first rigid support body side portion 960, a further rigid support body side portion 962 and an intermediate rigid support body portion 963. The two side portions and intermediate portion are secured to a base 966. The rigid support body thus includes two slits each of which can receive a respective end region of a respective tensile armour wire. A first slit is formed between opposed abutment surfaces provided by the further rigid support body side portion and a first side of the intermediate rigid support body portion. The further slit is provided by an abutment surface of the first rigid support body side portion 960 and a remaining side surface of the intermediate rigid support body portion 963. A cover 980 includes two respective downwardly extending ribs and can be secured via appropriate securing mechanisms to the rigid support body portions thereby securing the tensile armour wires within the slits where relative motion of the tensile armour wires is prevented by the teeth of the abutment surfaces. In this way each rigid support body can provide anchoring for multiple tensile wires.

According to certain embodiments described hereinabove a method of terminating flexible pipe body in an end fitting can be achieved by providing an end fitting body including a connecting flange at a first end and an open mouth at a further end, positioning an end region of one or more tensile armour wires of a segment of flexible pipe body through respective securing element bodies that includes teeth to resist subsequent withdrawal of the tensile armour wire from the rigid support body, securing a jacket member to the end fitting body thereby providing a pocket region within the end fitting where the tensile armour wire ends are located and subsequently providing a curable material in the pocket region. Aptly the curable material is an epoxy resin and this can subsequently be cured to inter the armour wire ends in epoxy material. The rigid support bodies affixed to the wires are difficult to pull through the epoxy and difficult to remove from the wires.

Throughout the description and claims of this specification, the words “comprise” and “contain” and variations of them mean“including but not limited to” and they are not intended to (and do not) exclude other moieties, additives, components, integers or steps. Throughout the description and claims of this specification, the singular encompasses the plural unless the context otherwise requires. In particular, where the indefinite article is used, the specification is to be understood as contemplating plurality as well as singularity, unless the context requires otherwise.

Features, integers, characteristics or groups described in conjunction with a particular aspect, embodiment or example of the invention are to be understood to be applicable to any other aspect, embodiment or example described herein unless incompatible therewith. All of the features disclosed in this specification (including any accompanying claims, abstract and drawings), and/or all of the steps of any method or process so disclosed, may be combined in any combination, except combinations where at least some of the features and/or steps are mutually exclusive. The invention is not restricted to any details of any foregoing embodiments. The invention extends to any novel one, or 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.

The reader’s 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.

Claims

CLAIMS:

1 . Apparatus for securing an end region of a tensile armour wire within a flexible pipe end fitting, comprising:

each abutment surface comprises a respective toothed region including teeth and a space between teeth of the first and further abutment surfaces is narrower at a root end of the slit proximate to a base region of the rigid support body than at an open mouth end of the slit distal to the base region, said space proximate to the base region comprising a region having a width that is equal to between 1 .0 and 0.90 times a wire width of a tensile armour wire that has a width of between 2 and 10 mm.

2. The apparatus as claimed in claim 1 , further comprising:

each toothed region comprises a plurality of teeth having an asymmetrical saw tooth profile including a long edge and a short edge, said long edge extending at an angle of less than 45° to a imaginary centre line of the slit, and said short edge extending at an angle of greater than 45° to the imaginary centre line.

3. The apparatus as claimed in claim 2, further comprising:

the configuration of the teeth of the toothed region of the first abutment surface is a mirror image of the configuration of the teeth of the toothed region of the further abutment surface.

4. The apparatus as claimed in claim 2 or claim 3, further comprising:

an apex line associated with a location of an apex point along a length of each tooth as it extends through a thickness of the support body is non-orthogonal to a plane of the base region of the support body.

5. The apparatus as claimed in any preceding claim, further comprising:

the space distal to the base region comprises a region having a continually increasing width up to the open mouth of the slit.

6. The apparatus as claimed in any preceding claim, further comprising: a cover member locatable over a surface of the rigid support body distal to the base region to cover the slit.

7. The apparatus as claimed in claim 6, further comprising:

the rigid support body and cover member each comprise cooperating securing elements to enable the cover to be permanently or releasably secured to the rigid support body.

8. The apparatus as claimed in claim 6 or claim 7, further comprising:

the cover member comprises at least one rib having a width that is locatable in the open mouth of the slit and that has a predetermined depth for locating an abutment end of the rib at a depth in the slit proximate to a side of a tensile wire located in the slit proximate to the base region.

9. The apparatus as claimed in any preceding claim wherein the rigid support body has a hardness greater than 12 HRc.

10. The apparatus as claimed in claim 9 wherein the hardness is greater than 30 HRc and optionally is greater than 40 HRc.

1 1 . The apparatus as claimed in any preceding claim, further comprising:

the rigid support body is securable to a free end region of a tensile armour wire so strongly that the wire breaks under tensile loading before the rigid support body pulls from the wire.

12. A method of securing an end region of at least one flexible pipe body tensile armour wire to an anchoring element, comprising the steps of:

13. The method as claimed in clam 12, further comprising:

urging the free end region by locating the tensile armour wire over the slit and pushing the tensile armour wire into the slit at a desired location a predetermined distance from the free end.

14. A method of terminating flexible pipe body in an end fitting, comprising the steps of:

urging a free end region of each tensile armour wire of a plurality of tensile armour wires, into a slit in a rigid support body that comprises at least one anchoring surface, between teeth of toothed regions of opposed abutment surfaces of the rigid support body;

subsequently preventing withdrawal of the tensile armour wire from the slit via teeth of the toothed regions which oppose movement of the rigid support body in a direction towards a free end of the tensile armour wire;

subsequently providing a curable material in the cavity void region.

15. The method as claimed in claim 14, further comprising:

locating a cover member that includes a rib over an open mouth end of the slit and securing the cover member to the rigid support body.

16. The method as claimed in claim 15, further comprising:

as the cover is secured to the rigid support body, locating an abutment end of the rib proximate to a side of a tensile armour wire located in the slit proximate to a root end of the slit.

17. The method as claimed in claim 14, 15 or 16, further comprising:

applying a load to the tensile armour wire of at least 50% of the structural capacity of the tensile armour wire to thereby confirm that the rigid support body and associated anchoring surface is secured at a desired location.

18. The method as claimed any one of claims 14 to 17, further comprising:

subsequently curing the material and thereby anchoring the tensile armour wire end regions in the cured material in the cavity void region via the rigid support bodies on each tensile armour wire end region.