Subsea termination assembly for umbilical

Abstract

The present invention relates to a subsea termination assembly for an umbilical and in particular to a termination assembly having improved means for anchoring steel strands of the umbilical to a termination, and to a method of forming a termination assembly. The subsea termination assembly has one or more steel strands and a plurality of other elongated umbilical elements, the termination assembly comprising a cavity into which said steel strands terminate, the cavity being filled with a filler material, wherein one or more of the steel strands has a collar thereon within the cavity to anchor the steel stand within the cavity, and a crimped arrangement around the steel strand comprising an outer sleeve and inner sleeve inserts to hold the collar on the steel strand.

Description

[0001] SUBSEA TERMINATION ASSEMBLY FOR UMBILICAL

[0002] The present invention relates to a subsea termination assembly for an umbilical and in particular to a termination assembly having improved means for anchoring steel strands of the umbilical to a termination, and to a method of forming a termination assembly.

[0003] Background

[0004] An umbilical consists of a group of one or more types of elongate active umbilical elements, such as electrical cables, optical fibre cables and fluid conveying conduits, cabled together for flexibility and over-sheathed and / or armoured for mechanical strength. Umbilicals are typically used for transmitting power, signals and fluids (for example for fluid injection, hydraulic power, gas release, etc.) to and from a subsea installation. The main fluid conduits used for manufacturing umbilical are thermoplastic hoses and steel tubes. API (American Petroleum Institute) 17E "Specification for Subsea Umbilicals", third edition, July 2003, provides standards for the design and manufacture of such umbilicals.

[0005] To bear the weight and tension of the umbilical, there are typically a series of steel strands alongside the elongate active umbilical elements. The steel strands and the other elongated umbilical elements that make up the umbilical are typically grouped together and wound in a helical or S / Z pattern. Examples of umbilicals are disclosed in the documents US6472614, WO93 / 17176 and GB2316990.

[0006] The steel strands are intended to service axial loads, and high external collapse pressures. In this way, the umbilical is able to withstand axial loads without requiring the addition of other strengthening members or tensile armour layers. A known method of umbilical termination is illustrated in Figure 1 . The method comprises welding the steel strands 2 forming part of the umbilical 1 to a steel bulkhead plate 3 through which the steel strands 2 pass and which is mechanically attached to the termination 4. The interior cavity of the termination 4 is filled with a compression resistant resin 5, gravity poured, through a filler hole situated at the top of the termination 4. In this application, the resin 5 is used to prevent straightening of the strands 2, i.e. to prevent radial displacement of the strands 2 within the termination 4. Tensile loads are transmitted through the steel strands 2 directly to the bulkhead plate 3 and thus to the termination 4, therefore the resin does not comprise a primary load bearing mechanism.

[0007] The welding process is very time consuming, costly and labour intensive and may harm polymer layers by heat from the welding, such as electrical cable sheathing and insulation material.

[0008] Meanwhile, other methods are known for anchoring steel tubes and rods within the interior cavity of an umbilical termination, but such methods rely on welding or another heat treatments of the tube or rod to achieve the anchoring. Such tubes and rods are sufficiently thick and / or a single massive component to withstand the welding or heat treatment without leading to any significant structural change in the metal microstructure, i.e. without affecting the mechanical properties and thus the strength of the tube or rod, (and so without affecting the purpose of the tube or rod to withstand axial and tension loads on the subsea umbilical in use).

[0009] The invention aims at solving the problem of anchoring of the steel strands of an umbilical at a termination or other connection to extend the length of the umbilical. It is desirable that the termination can be done cost effectively and without a cumbersome arrangement. It is also desirable that the termination can be created or realized in situ, for example off shore and subsea. Summary

[0010] According to a first aspect of the present invention, there is provided a subsea termination assembly for an umbilical having one or more steel strands and a plurality of other elongated umbilical elements, the termination assembly comprising a cavity into which said steel strands terminate, the cavity being filled with a filler material, wherein one or more of the steel strands has a collar thereon within the cavity to anchor the steel stand within the cavity, and a crimped arrangement around the steel strand comprising an outer sleeve and inner sleeve inserts to maintain the collar on the steel strand.

[0011] According to a second aspect of the present invention, there is provided a method of assembling a subsea termination assembly for an umbilical having one or more steel strands and a plurality of other elongated umbilical elements, comprising at least the steps of; terminating the steel strands in a cavity in the subsea termination assembly, locating a collar on one or more of the steel strands within the cavity; locating an outer sleeve and inner sleeve inserts on the steel strand; crimping the outer sleeve and inner sleeve inserts onto the steel strand to maintain the collar on the steel strand; and filling the cavity with a filler material to anchor the steel strand within the cavity.

[0012] Discussion of the drawings

[0013] Embodiments of the present invention will now be described by way of example only, with reference to the accompanying drawings, in which: Fig. 1 is a longitudinal sectional view through a known umbilical termination assembly;

[0014] Fig. 2 is a longitudinal sectional view through a first umbilical termination assembly according to an embodiment of the present invention;

[0015] Fig. 3 is a schematic longitudinal sectional view through a second umbilical termination assembly according to an embodiment of the present invention;

[0016] Fig. 4 is a side view of a steel strand end;

[0017] Fig.s 5a to 5f are a series of perspective views of a first forming an umbilical termination assembly according to a further embodiment of the present invention; and

[0018] Fig.s 6a to 6f are a series of perspective views of a second forming an umbilical termination assembly according to a further embodiment of the present invention.

[0019] Detailed description

[0020] The present invention discloses a subsea termination assembly for an umbilical having one or more steel strands and a plurality of other elongated umbilical elements, the termination assembly comprising a cavity into which said steel strands terminate, the cavity being filled with a filler material, wherein one or more of the steel strands has a collar thereon within the cavity to anchor the steel stand within the cavity, and a crimped arrangement around the steel strand comprising an outer sleeve and inner sleeve inserts to maintain the collar on the steel strand.

[0021] The umbilical comprises a group of one or more types of elongate active umbilical elements, such as electrical cables, optical fibre cables and fluid conveying conduits, cabled together for flexibility and over-sheathed and / or armoured for mechanical strength.

[0022] Umbilicals are typically used for transmitting power, signals and fluids (for example for fluid injection, hydraulic power, gas release, etc.) to and from a subsea installation. The main fluid conduits used for manufacturing umbilicals are thermoplastic hoses and steel tubes. API (American Petroleum Institute) 17E "Specification for Subsea Umbilicals", third edition, July 2003, provides standards for the design and manufacture of such umbilicals.

[0023] The term “umbilical” as used herein relates to a fluid carrying umbilical, or to a ‘service’ umbilical such as a power cable, or a signal cable, or any combination of same, such as an integrated service bundle.

[0024] The steel strands generally comprise a steel core surrounded by a series of individual steel wires, and typically over-sheathed with a protective coating, usually a plastic or polymer coating. The steel wires can each have any suitable thickness, and are generally each in the range of 2mm to 10mm thick, such as in the range 4-6mm thick. A steel strand can be in the range 10mm to 20 mm or more in overall thickness or diameter.

[0025] Optionally, the steel strands are or form the umbilical strengthening members.

[0026] Optionally, the steel strands are formed from at least a plurality of individual wires or elements. Optionally, such elements or wires have an outer diameter in the range 2-10mm, preferably in the range 4-6mm.

[0027] The collar defines a region of increased localised diameter around the steel strand. The collar has an aperture to allow the steel strand to fit through it.

[0028] Optionally, the collar is formed from a metal being the same as or compatible to the steel of the steel strand.

[0029] The collar can be modified to present one or more further load bearing faces, for example by means of one or more regions of reduced diameter. Optionally, the outer sleeve and the inner sleeve inserts are formed from a metal being the same as or compatible to the steel of the steel strand.

[0030] The inner sleeve inserts may have shape, form or design, that is able to be combined to form a complete shape around a steel strand. One shape for the inner sleeve inserts comprises half collars or half shells, including longitudinal half-cylinders or semi-cylinders, which, when brought together on either side of a steel strand, form a complete cylinder. Half cylinders are sometimes terms ‘half shells’. The inner sleeve inserts may be ‘hollow’, where part of the steel strand fits within the hollow part.

[0031] Other shapes are possible to form other final shapes once combined around the steel strand. The final outer shape of the combined inner sleeves could be complementary to the crimping tool or process subsequently used.

[0032] The inner sleeves can have an inner groove, cutaway or hollow to match the part of the steel strand they are intended to form against, so that the combined inner sleeves form a combined ‘inner surface’.

[0033] In one embodiment, the inner sleeve inserts may be formed from a material that is deformable under pressure, particularly under substantial pressure, so as to form a crimped arrangement directly with the outer parts or surface of the steel strand.

[0034] In another embodiment, the inner sleeve inserts may be fully or partly formed from a material that is harder than a steel strand, so that the steel strand is deformable under pressure, particularly under substantial pressure, so as to form a crimped arrangement directly with the inner parts or surface of the sleeve inserts. The outer sleeve may have any shape, form or design able to fit around the inner sleeve inserts once the inner sleeve inserts are located around the steel strand to form their combined shape.

[0035] In one embodiment of the present invention, the outer sleeve is a cylinder, generally having an inner diameter being the same as, close to or tight to the outer diameter of the shape or the outer surface of the inner sleeve inserts once combined and located around the steel strand.

[0036] The outer sleeve and inner sleeve inserts may have the same or approximately the same longitudinal (relative to the steel strand) length, or may have different lengths. For example, the outer sleeve may be longer than the inner sleeve inserts, so as to further form a crimped sleeve around one or both ends of the inner sleeve inserts in the final crimped arrangement. In another example, the outer sleeve includes a reduced diameter end to abut the ends of the inner sleeve inserts.

[0037] Optionally, the outer surfaces of the inner sleeve inserts are wholly or substantially patterned. Optionally, the inner surfaces of the inner sleeve inserts are wholly or substantially patterned. Optionally, both the outer and inner surfaces of the inner sleeve inserts are wholly or substantially patterned.

[0038] The patterning may have any shape, form or design, generally intended so as to be not ‘smooth’, and achieve a form of patterning across either all or a substantive part of the outer and / or inner surface.

[0039] The patterning may be regular or irregular, or may be different in one or more parts of the outer and / or inner surfaces of the inner sleeve inserts.

[0040] Optionally, the outer surfaces of the inner sleeve inserts are knurled. Knurling is a finishing process used to create a combination of horizontal, vertical or crossing lines on a surface, typically to form a diamond-patterned texture to the outer and / or inner surface of a product. Knurling typically creates a textured surface that can increase intended engagement with another surface. Knurling is typically applied by a machine, and is not further described herein.

[0041] Optionally, the inner surfaces of the inner sleeve inserts are teethed or grooved or both. Optionally, any such teeth, grooves or indeed all of the inner sleeve inserts, are formed from a material that is harder or hardened relative to the steel of the steel strand, so that the teeth and / or grooves are able to bite into the steel strand when crimped together.

[0042] There is a crimped arrangement formed around the steel strand comprising the outer sleeve and the inner sleeve inserts, in order to maintain the collar on the steel strand. The crimped arrangement involves any form of crimping. Crimping is generally intended to be a form of compression, able to bond or fix two or more items, generally involving metals or being metallic, together, to form a join thereinbetween.

[0043] Typically, crimping is a cold-working technique. Typically, crimping does not require any welding or other heat application to form a strong join between the relevant items. By being a cold-working technique, the crimping does not thermally affect the steel strands, and does not therefore affect the mechanical properties and thus the strength of the steel strands. This maintains the purpose of the steel strands and the overall strength members in the umbilical, to withstand axial and tension loads on the subsea umbilical in use.

[0044] As mentioned above, steel strands are formed of relatively thinner elongated wires or elements, each having a thickness or an outer diameter significantly smaller than the thickness or outer diameter of the solid tubes or rods typically used in the art, which can be more than 50mm thick. By being thinner, steel strands and their individual wires or elements are more susceptible to deterioration of their mechanical properties during a heat treatment, which can locally modify the steel microstructure and so lower the mechanical properties of the steel strand material. This deterioration effect is especially detrimental to higher grade steels with their high mechanical properties, as it is typically the case for subsea umbilical strengthening members. Therefore, avoiding a thermal treatment to the steel strands to place a collar does not affect the mechanical properties of the said steel strands, and so does not decrease the mechanical performance of the umbilical.

[0045] Optionally, the crimped arrangement is a cold-crimped arrangement, i.e. not involving any heat treatment, welding or other heating of the steel strands.

[0046] Forms of crimping include pressing, die-pressing, hydraulic pressing, pneumatic pressing, and swaging. Swaging is a metal-forming technique in which the metal of one part is deformed to fit around another part by pressing or hammering, or by forcing the combined parts through a die. Swaging is a forging process in which the dimensions of the metal items or parts are altered, typically compressed or squeezed together, to form a strong join thererinbetween. Swaging is a form of metal working to achieve a combined final metal shape.

[0047] Optionally, one or more of the outer sleeve, inner sleeve inserts and steel strand, are plastically deformed against each other to achieve the crimped arrangement around the steel strand, and thereby to maintain and hold the collar on the steel strand.

[0048] Optionally, the outer sleeve and the inner sleeve inserts are swaged on to the steel strand.

[0049] The subsea termination assembly of the present invention may comprise a tensile connection to another umbilical, in order to extend the function of one or more of the elongated umbilical elements in the umbilical, to another umbilical.

[0050] Optionally, the subsea termination assembly of the present invention is at a termination of an umbilical, such as to terminate the functions of the umbilical at a next processing or work station, either above the sea or subsea.

[0051] Optionally, the umbilical used in the present invention is a power cable or a fluid umbilical.

[0052] Optionally, the filler material comprises a hard setting compound such as, for example, an epoxy, polyester, vinylester or phenolic curable resin. Suitable resin materials, such as epoxy, comprise a base resin, an accelerator and / or hardener and preferably a filler medium suspended interstitially within the resin. The solid filler medium is used primarily as the compression resistant medium, held in suspension within the resin compound. In addition, extra filler medium can be added to increase the viscosity of the mixed compound and reduce exotherming temperatures.

[0053] Optionally, the filler material further comprises spheroidal glass beads. In the present application, "spheroidal beads" should be understood as bodies having a substantially spherical shape, that may or may not be perfectly round or spherical, that may or may not have uniform sizes and shapes, and that may be solid or hollow. Resin can be mixed with the spheroidal glass beads with or without small grain interstitial filler medium and gravity poured into the termination or, alternatively, resin can be injected into the termination to fill the interstitial spaces, created between the dry spheroidal glass beads which have been previously introduced into the termination. Optionally an interstitial filler medium, such as sand or spheroidal glass micro-beads, is also provided. In the present application, "spheroidal micro-beads" should be understood as bodies having a similar shape as the spheroidal beads, but with much smaller dimensions. The relative small size of the spheroidal micro-beads enables them to fill the interstices between the spheroidal beads.

[0054] Once assembled, the termination cavity may be filled, under gravity, with the hard setting compound, through a filler hole typically situated at the top of the termination. Alternatively, the resin compound may be injected into the cavity under pressure through one or more inlets.

[0055] The present invention also provides a method of assembling a subsea termination assembly for an umbilical having one or more steel strands and a plurality of other elongated umbilical elements, comprising at least the steps of; terminating the steel strands in a cavity in the subsea termination assembly, locating a collar on one or more of the steel strands within the cavity; locating an outer sleeve and inner sleeve inserts on the steel strand; crimping the outer sleeve and inner sleeve inserts onto the steel strand to maintain the collar on the steel strand; and filling the cavity with a filler material to anchor the steel strand within the cavity.

[0056] The nature and embodiments of the umbilical, the steel strands, the collar, the outer sleeve and the inner sleeve inserts are as described hereinabove, and apply also and equally to the method of assembling as described herein.

[0057] The step of terminating the steel strands in a cavity in a subsea termination assembly requires location of the ends of the steel strands within the cavity in any manner.

[0058] This step of locating a collar around the end of a steel strand comprises the location of a collar having an aperture therein at or near the end of the steel strand, typically by sliding the collar onto the end of the steel strand. This creates a transverse surface around the steel strand at a localised region.

[0059] Where the steel strand has an over-sheath as described hereinabove, the over-sheath may be cut away or cut back, and the collar could be located against or near the end of the over-sheath. An additional pre-former outer sheath sleeve can be located around the steel strand prior to the location of the collar, so as to form a subsequent oversheath over the steel strand on the side of the collar opposite to the crimped arrangement being formed.

[0060] The step of locating an outer sleeve and inner sleeve inserts on the steel strand may comprise the location of the inner sleeve inserts around the end of the steel strand beyond the collar, optionally at or near the end of the steel strand without any over-sheathing. As described above, the inner sleeve inserts may have any form, shape or design, generally intended to create a surround, preferably a complete surround, to the steel strand once the inserts are all located on and around the steel strand.

[0061] Where the inner sleeve inserts comprise two half-shell sleeve inserts, such inserts may be located one on each side of the steel strand so as to form, once brought together, a complete cylindrical surround to the steel strand. The skilled man can recognise that other forms or numbers of inserts can be used to form a suitable combined surround to the steel strand.

[0062] Optionally, the present invention uses inner sleeve inserts with teeth and / or a longitudinal core or groove having an inner diameter that is close to or the same as the outer diameter of the steel strand at the point of fitting, and an outer diameter that is up to the size of the outer diameter of the collar. Optionally, the inner sleeve inserts are elongate.

[0063] The outer sleeve may have any suitable shape, form or design, able to be located over the inner sleeve inserts once the inner sleeve inserts are located around and on to the steel strand. Optionally, the outer sleeve is a hollow cylinder, having an inner diameter that is the same as or close to the outer diameter of the inner sleeve inserts once located around the steel strand.

[0064] The crimping of the outer sleeve and the inner sleeve inserts on to the steel strand to hold the collar of the steel strand may be achieved using any suitable process or processing. The crimping may be achieved by a suitable tool or apparatus, generally involving one or more hardened faces or dies, able to locate around the outer sleeve and achieve crimping of the outer sleeve and inner sleeve inserts together, and on to and against the steel strand.

[0065] One form of crimping is swaging of the outer sleeve and the inner sleeve inserts on to the steel strand. Optionally, the swaging is cold-working, (i.e. not involving any heat treatment, welding or other heating of the steel strands), and involves a forging process using compressive forces to deform the shape of the outer sleeve and the inner sleeve inserts. Swaging can be typically a tube process or a radial process intended to achieve the desired plastic deformation.

[0066] The crimping of the outer sleeve and inner sleeve inserts on to the steel strand creates a sufficient bond or join to hold the collar on to the steel strand against tensile forces that occur during the laying and use of the umbilical in a subsea environment. Such forces are typically created and extend over a significant distance.

[0067] Optionally, the step of crimping the outer sleeve and the inner sleeve inserts onto the steel strand comprises axial die-compression of the outer sleeve and the inner sleeve inserts onto, and optionally into, the steel strand.

[0068] The filling of the cavity with a filler material anchors the steel strand within the cavity. The nature of a filler material is described hereinabove, and the filling can be achieved through one or more suitable ports or portals in the outer surface of the termination assembly, so as to form a final hardened internal material around the crimped arrangements of the outer sleeve and inner sleeve inserts and collars, to achieve increased weight bearing transfer between the steel strands and the subsea termination assembly.

[0069] Optionally, the method includes the step of patterning the outer and / or inner surfaces of the inner sleeve inserts. The patterning may have any shape, form or design, generally intended so as to be not ‘smooth’, and achieve a form of patterning across either all or a substantive part of the outer and / or inner surface.

[0070] The patterning may be regular or irregular, or may be different in one or more parts of the outer and / or inner surfaces of the inner sleeve inserts.

[0071] Optionally, the step of patterning is knurling the outer surface of the inner sleeve inserts.

[0072] Optionally, the step of patterning comprises teething, or grooving or teething and grooving the inner surfaces of the inner sleeve inserts.

[0073] Turning to the drawings, Figure 2 is an example of a first umbilical termination assembly 10 comprising a first plate 11 having an aperture through which the end of an umbilical 12 enters, and a second plate 13 having a plurality of apertures therein, through which the various umbilical elements, including electrical cables and / or optical fibre cables 14 and steel tubes 15, can pass for connection to suitable hose fittings in a manner known in the art. A cavity 17 is defined between the first and second plates through which the umbilical elements pass.

[0074] Figure 2 also shows three steel strands 20 terminating in the cavity 17 of the termination assembly 10, the steel strands 20 being part of the umbilical 12 designed to take the axial load of the umbilical 20 during laying and use. Around the end of each steel strand 20 is a collar 22 and a crimped arrangement 24, the crimped arrangement 24 around the steel strand 20 comprising an outer sleeve and inner sleeve inserts, as described hereinafter in more detail, to maintain and hold the collar 22 on the steel strand 20. One may therefore realize the termination without welding.

[0075] The cavity 17 of the first termination assembly 10 is filled with a compression resistant filler material, to fix the steel strands 20 and other umbilical elements in place within the termination assembly 10, and to anchor the load bearing steel strands 20 within the termination assembly 10 to withstand tensile forces applied to the umbilical 12.

[0076] Figure 3 shows a schematic second termination assembly 30 for an umbilical 32 having a number of elongated umbilical elements 34 intended to continue, either directly or indirectly through suitable connectors, on to another umbilical or similar. The second termination assembly 30 has a cavity 31 , through which the umbilical elements 34 pass, but within which at least one of the steel strands 36 of the umbilical 32 terminate. Figure 3 shows symbolically two such steel strands 36.

[0077] Near the ends of the steel strands 36 are located collars 37 and crimped arrangements 38. The crimped arrangements 38 are around the steel strands 36 and involve an outer sleeve and inner sleeve inserts (not shown in detail) to hold the collars 37 on to the steel strands 36 in a manner as described herein.

[0078] The second subsea termination assembly 30 shows a form of interconnection or extension for an umbilical 32, to allow the continuing functioning of one or more of the functional elements of the umbilical thereafter. The cavity 31 can be filled with a suitable filler material 39 such as a resin as described herein. Figure 4 shows a steel strand 40 comprising a series of steel strands, optionally with a steel core, in the form of a winding 42. The winding is generally wound in a helical manner around the core, so as to help achieve a combined tensile loading along the steel strand 40. The steel strand 40 also has a protective over-sheath 44, which is shown cut back to expose the winding 42 near the end of the steel strand 40. The steel strand 40 can be one of the steel strands 20, 30 shown in Figures 2 and 3, and can be workable before the final forming of a termination or connection is made, (and the cavity therewithin is formed).

[0079] Figures 5a to 5f are a series of steps showing an example of a first method of assembling a subsea termination assembly collar and crimping arrangement for use as part of the subsea termination assembly as described herein.

[0080] Figure 5a shows a collar 50 locatable on to the steel strand 40 of Figure 4 from one free end thereof. The collar 50 has an enlarged diameter relative to the steel strand 40, and has a central aperture 52 having a diameter that is the same as or close to or tight to the outer diameter of the windings 42 of the steel strand.

[0081] Figure 5b shows the completed arrangement of the location of the collar 50 abutting the end of the over-sheath 44 on the steel strand 40.

[0082] Figure 5c shows two inner sleeve inserts 54 being half-shells, and being formed as having the same shape and dimensions. The outer surface of each of the inner sleeve inserts 54 is knurled. The inner diameter of the halfsleeve inserts 54 is the same as or close to or tight to the outer diameter of the windings 42 of the steel strand 40, so that the location of the two inner sleeve inserts 54 form a complete shell around the steel strand 40 once brought together in a manner shown in Figure 5d. Figure 5d shows an outer sleeve 60 in the form of a hollow cylinder, having an inner diameter that is the same as or close to or tight to the outer diameter of the inner sleeve inserts 54 once located around the steel strand 40. In a simple arrangement, the outer sleeve 60 can be suitably located and pushed to form a snug, possibly interference fit, around the inner sleeve inserts 54.

[0083] Figure 5e shows two symbolic die end parts 62 of a swaging tool, so as to form a pressing or compressing die shape having a tapered inner surface. Swaging is a process known in the art, and typically involves the forced pressing of the die against the outer surface of overlapping metal parts.

[0084] The load spreading collar 50 is optionally a suitable distance apart from the outer sleeve 60 and the swaging tool die parts 62 (not shown) to avoid interfering with the swaging process. After the outer sleeve 60 has been pushed through the swaging tool, the load spreading collar 50 can be moved closer to or next to the outer sleeve 60.

[0085] In the present invention, the inner surface 64 of the swage tool end parts 62 are forced against the outer surface of the outer sleeve 60 in a manner known in the art, to plastically deform the outer sleeve 60 and / or the inner sleeve inserts 54 and / or the steel strand 40 against each other. In this way, the crimped arrangement 66 achieved in the swaging process shown in Figure 5e serves to maintain the collar 50 in place on the steel strand 40 in a way that allows tensile transfer of loading on the steel strand 40 to a termination assembly, (such as the first termination assembly 20 shown in Figure 2 or the second termination assembly 30 shown in Figure 3).

[0086] The crimped arrangement 66 is shown in Figure 5f. The load spreading collar 50 is designed so as to take the full tensile load of the steel strand 40 to the encapsulating resin. Figures 6a to 6f are a series of steps showing an example of a second method of assembling a subsea termination assembly collar and crimping arrangement for use as part of the subsea termination assembly as described herein.

[0087] Figure 6a shows a collar 70 locatable on to the steel strand 40 of Figure 4 from one free end thereof. The collar 70 has an enlarged diameter relative to the steel strand 40. Figure 6a also shows a heat shrink sleeve 72 as a preformer oversheath discussed hereinafter, located over the end of the oversheath 44 still on the steel strand 40 prior to location of the collar 70.

[0088] Figure 6a also shows a swaging assembly 80, comprising one end of an assembly rig 82 and a die 84 having an inner restricted throat 86 between the ends of the die 84. Figure 6a also shows two inner sleeve inserts 74 and an outer sleeve 76 ready for use.

[0089] In Figure 6b, the swaging assembly is located around the steel strand 40, and the two inner sleeve inserts 74 and outer sleeve 76 are located around a free end of the steel strand 40 extending beyond the swaging assembly 80. The inner surface of the half-sleeve inserts 74 include hardened grooves and / or teeth (not shown), and the inner diameter of the inserts 74 is the same as or close to or tight to the outer diameter of the windings of the steel strand 40, so that the location of the two inner sleeve inserts 74 form a complete shell around the steel strand 40 once brought together in a manner shown in Figure 6b.

[0090] Figure 6b also shows the end of an aligned pusher rod 88, having an enlarged head with a hollow 90 to accommodate the end of the steel strand 40 but not the outer sleeve 76.

[0091] Figure 6c shows the pusher rod 88, pushed by a suitable ram or similar (not shown), acting against the end of the outer sleeve 76 to push the outer sleeve 76 and inner sleeve inserts 74 into the throat 86 of the die 84 against the assembly rig 82 so as to compress the outer sleeve 76, the inner sleeve inserts 74 and the steel strand 40 together. The hardened grooves and / or teeth of the inner sleeve inserts 74 bite into the steel strand 40 to help anchor and crimp them together.

[0092] After the outer sleeve 76 has been pushed through the die 84, the swaging assembly 80 and pusher rod 88 are withdrawn to leave the crimped arrangement 94 as shown in Figure 6d.

[0093] In Figure 6e, the collar 70 can be moved closer to or next to the crimped arrangement 94, held in place by a suitable tie 98, prior to the addition of a heat shrink cap 100 around the crimped arrangement 94, and relocation of the heat shrink sleeve 72 over the free steel strand 40 on the other side of the collar 70. The heat shrink sleeve 72 is heat-shrinked into a protective position as shown in Figure 6f. Figure 6f shows a complete arrangement for the steel strand 40 ready for use in part of a subsea termination assembly as described herein.

[0094] It is a particular feature of the present invention that no heat treatment or welding is required to achieve the holding of the collar on to a steel strand. For example, the crimping process requires merely a hydraulic cylinder, excluding the need for any heat generation or treatment, and providing mobility of the invention. In this way, the present invention can be carried out both onshore, offshore, or even subsea, and can be carried out anywhere along the length of an umbilical. The use of any high temperatures is avoided.

Claims

CLAIMS1. A subsea termination assembly for an umbilical having one or more steel strands and a plurality of other elongated umbilical elements, the termination assembly comprising a cavity into which said steel strands terminate, the cavity being filled with a filler material, wherein one or more of the steel strands has a collar thereon within the cavity to anchor the steel stand within the cavity, and a crimped arrangement around the steel strand comprising an outer sleeve and inner sleeve inserts to maintain the collar on the steel strand.

2. A subsea termination assembly as claimed in claim 1 , wherein the outer and / or inner surfaces of the inner sleeve inserts are patterned.

3. A subsea termination assembly as claimed in claim 2, wherein the outer surfaces of the inner sleeve inserts are knurled.

4. A subsea termination assembly as claimed in claim 2 or claim 3, wherein the inner surfaces of the inner sleeve inserts are teethed or grooved or both.

5. A subsea termination assembly as claimed in any preceding claim, wherein the assembly comprises a tensile connection to another umbilical.

6. A subsea termination assembly as claimed in any preceding claim, wherein the umbilical is a power cable or a fluid umbilical.

7. A subsea termination assembly as claimed in any preceding claim, wherein the steel strand comprises a central core and a plurality of outer wires wound around the core.

8. A subsea termination assembly as claimed in any preceding claim, wherein one or more of the outer sleeve, inner sleeve inserts and steel strand, are plastically deformed against each other.

9. A subsea termination assembly as claimed in claim 8, wherein the outer sleeve and inner sleeve inserts are swaged onto the steel strand.

10. A subsea termination assembly as claimed in any preceding claim, wherein the inner sleeve inserts comprise two half-shell sleeve inserts.

11. A subsea termination assembly as claimed in any preceding claim, wherein the inner sleeves around the steel strand have an inner diameter that is the same as the outer diameter of the steel strand, and the outer sleeve has an inner diameter that is the same as the outer diameter of the inner sleeves around the steel strand.

12. A method of assembling a subsea termination assembly for an umbilical having one or more steel strands and a plurality of other elongated umbilical elements, comprising at least the steps of; terminating the steel strands in a cavity in the subsea termination assembly, locating a collar on one or more of the steel strands within the cavity; locating an outer sleeve and inner sleeve inserts on the steel strand; crimping the outer sleeve and inner sleeve inserts onto the steel strand to maintain the collar on the steel strand; and filling the cavity with a filler material to anchor the steel strand within the cavity.

13. A method as claimed in claim 12, wherein the step of crimping the outer sleeve and the inner sleeve inserts onto the steel strand comprises plastic deformation of one or more of the outer sleeve, inner sleeve inserts and steel strand, against each other.

14. A method as claimed in claim 13, wherein the step of crimping the outer sleeve and the inner sleeve inserts onto the steel strand comprises swaging of the outer sleeve and the inner sleeve inserts onto the steel strand.

15. A method as claimed in any one of claims 12 to 14, wherein the step of crimping the outer sleeve and the inner sleeve inserts onto the steel strand comprises axial die-compression of the outer sleeve and the inner sleeve inserts onto the steel strand.

16. A method as claimed in any one of claims 12 to 15, comprising the further step of patterning the outer and / or inner surfaces of the inner sleeve inserts prior to location on the steel strand.

17. A method as claimed in claim 16, wherein the patterning comprises of knurling the outer surfaces of the inner sleeve inserts.

18. A method as claimed in claim 16 or claim 17, wherein the patterning comprises teething, or grooving or teething and grooving the inner surfaces of the inner sleeve inserts.

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