EP3052850A1

EP3052850A1 - Stand-off clamp for pipeline repair

Info

Publication number: EP3052850A1
Application number: EP14850192.7A
Authority: EP
Inventors: Wei Siang Sum; Kok Hoong Leong; Yin Liong Leong; Luke Philip DJUKIC; Paul Joseph FALZON; Timothy William ECCLESHALL; Jeffrey Richard De Jong; Mathew STOESSIGER; Bruce Cartwright
Original assignee: Petroliam Nasional Bhd Petronas
Current assignee: Petroliam Nasional Bhd Petronas
Priority date: 2013-10-01
Filing date: 2014-09-26
Publication date: 2016-08-10
Also published as: AU2014101650A4; DE202014010875U1; RU189577U9; RU189577U1; KR20190002041U; CN208750272U; WO2015050428A1; KR20200001863U; MY183132A; KR200494964Y1; KR20160092994A; RU2016117139A; AU2014330169A1

Abstract

A clamp for repairing a section of pipeline, and a method for preparing a pipeline, are proposed. The clamp comprises a plurality of clamp portions (12) and a seal (30) disposed on an internal surface (42) of at least one of the plurality of clamp portions (12). The clamp portions are fastenable to each other such that the clamp portions and the seal cooperate to enclose the section of pipeline (20) in a channel therebetween, with the seal (30) bearing against a surface of the section of pipeline (20). The clamp portions (12) comprise a polymer-based composite material.

Description

STAND-OFF CLAMP FOR PIPELINE REPAIR

Technical field

This invention relates to a clamp for repair of leaks and for strengthening of pipe in a pipeline, for example an oil or gas pipeline. Background

In the oil and gas industry, raw and processed materials are conveyed by flow along pipelines which comprise joined tubing sections located both underwater and above ground. The tubing sections can periodically develop leaks or points of weakness due to erosion, corrosion or mechanical damage. To repair the leak or point of weakness without needing to stop operation of the pipeline, one previously proposed solution is to encase the damaged section with a steel clamp. However, metal clamps are prone to corrosion, whether in storage or in the field. They also add weight to the repaired structure. Depending on the size, they may also take longer to manufacture and install. Accordingly, repairs using metal clamps may involve significant cost, complexity and delay.

It would be desirable to provide a clamp for repairing sections of pipeline which overcomes or alleviates the above disadvantages, or which at least provides a useful alternative.

Summary of Invention In a first aspect, the present invention provides a clamp for repairing a section of pipeline, the clamp comprising:

a plurality of clamp portions; and

a seal disposed on an internal surface of at least one of the plurality of clamp portions;

wherein the clamp portions are fastenable to each other such that the clamp portions and the seal cooperate to enclose the section of pipeline in a channel therebetween, with the seal bearing against a surface of the section of pipeline; and wherein the clamp portions comprise a polymer-based composite material.

In certain embodiments, two or more of the clamp portions each comprise at least one flange, the clamp being fastenable in place on the pipeline section by securing respective flanges of the respective clamp portions. The flanges may each have at least one aperture formed therein, a fastener being receivable in said aperture to secure respective flanges together. The clamp portions may be identical to each other.

Preferably, there are two clamp portions. The clamp may comprise a seal member disposed on an internal surface of each clamp portion. The seal members may be configured to cooperate to collectively form a circumferential seal around the pipeline section. Each seal member may comprise first and second opposed end portions, and first and second opposed side portions extending between the first and second end portions. In certain embodiments, at least one seal member covers the internal surface of the clamp portion on which it is disposed.

Respective end portions of adjacent pairs of the seal members may be configured to abut against each other, such that the end portions collectively form continuous seals around a circumference of the pipe.

At least one pair of clamp portions of the clamp may be joined by a hinge.

In embodiments of the invention, at least one of the clamp portions is formed from a polymer-based composite shell surrounding a core material. The core material may be selected from the group comprising: a closed-cell polymer foam; a syntactic foam; or a metal, composite or graphite honeycomb material.

Preferably, the polymer-based composite material comprises a fibre-reinforced polymer. At least one clamp portion may be internally and/or externally lined or coated with a chemical-resistant and/or fire-resistant and/or low-permeability material. In a second aspect, the present invention provides a method of repairing a section of pipeline, the method comprising:

providing a clamp according to any of the above described embodiments;

positioning the clamp portions around the section of pipeline; and

securing the clamp portions to each other;

whereby the plurality of clamp portions and the seal cooperate to enclose the pipeline section in a channel therebetween, with the seal bearing against a surface of the pipeline section. The method may further comprise applying grout to an internal surface of at least one of the clamp portions. The grout may be applied by injection into the channel, for example. The grout may be applied in an annular region bounded by the pipe and the clamp.

The method may further comprise applying at least one layer of a fibre or adhesive tape material to a weakened or damaged region of the section of pipeline prior to securing the clamp portions to each other.

In a further aspect, the present invention provides a method of manufacturing a clamp for repairing a section of pipeline, comprising:

forming a plurality of clamp portions, the clamp portions each comprising a polymer-based composite material; and

disposing a seal on an internal surface of at least one of the clamp portions; wherein the clamp portions are fastenable to each other such that the clamp portions and the seal cooperate to enclose the section of pipeline in a channel therebetween, with the seal bearing against a surface of the section of pipeline.

The method may comprise surveying said pipeline; and based on the results of said surveying, forming said clamp portions. The clamp portions may be formed by one or more of: resin vacuum infusion, filament winding, a pre-preg process, a wet layup process, or resin transfer moulding. Preferably, the polymer-based composite material comprises a fibre-reinforced polymer. Brief Description of the Drawings

It will be convenient to further describe the present invention with respect to the accompanying drawings that illustrate possible arrangements of the invention. Other arrangements of the invention are possible, and consequently the particularity of the accompanying drawings is not to be understood as superseding the generality of the preceding description of the invention.

Figure 1 shows a clamp according to an embodiment, in place on a pipeline section; Figure 2 shows portions of the clamp being brought into engagement with the pipeline section;

Figure 3 shows an isometric view of a first portion of the clamp;

Figure 4 is a top projection view of the first clamp portion;

Figure 5 is an isometric view of an alternative clamp portion; Figure 6 shows an alternative embodiment of a clamp, in use at a bend in a pipeline;

Figure 7 shows a further alternative embodiment of a clamp, in a partially open configuration;

Figure 8 shows the clamp of Figure 7 in a closed configuration; Figure 9 is a cross-sectional view through the clamp of Figure 7; Figure 10 is a cross-sectional view through yet another embodiment of a clamp; Figure 1 1 is an exploded view of a further embodiment of a clamp; and Figure 12 is a cross-section through the clamp of Figure 1 1 , installed on a pipe section. Detailed Description

Embodiments of the invention relate to a clamp comprising composite part-cylinders with resilient (e.g. rubber or another elastomeric or polymeric material) seals that can be brought together over a section of pipe. The clamp portions may be held together via fasteners that are preferably equally spaced on flanges along their length. Embodiments also relate to a method of making a clamp, and a method of repairing a pipeline using a clamp.

The embodiments described below largely relate to a clamp comprising two clamp portions, preferably two components having half-cylindrical internal cross-section. However, it will be appreciated that alternative embodiments may employ three or more clamp portions, which may (but need not be) substantially identical to each other. For example, if the clamp comprises four clamp portions then each clamp portion may have a quarter-cylindrical cross-section. In certain embodiments the clamp portions may have different sizes. For example, if there are three clamp portions then one of the clamp portions may be half-cylindrical while the other two are quarter-cylindrical. Many other ways of dividing the clamp into two or more components are possible. Features of the embodiments described below may equally apply to configurations which employ three or more clamp portions.

Referring initially to Figures 1 and 2, there is shown a clamp 10 including a first clamp portion 12 and a second clamp portion 14. The clamp portions 12, 14 are each substantially half-cylindrical and each have an internal surface sized and shaped to accommodate a straight pipeline section 20 to be repaired. The clamp 10 can be located around the position of a leak or section of weakness of pipe 20, forming a sleeve extending longitudinally along the pipe. As will later be described in more detail, the two clamp portions 12, 14 each have a sealing member disposed on their internal surfaces, such that when fastened around the pipe 20, the respective sealing members cooperate to form a tight seal around the leak or section of weakness. The clamp portions 12, 14 may be substantially identical in construction, but need not be, provided that they form an appropriate seal about the pipe 20. The first 12 and second 14 clamp portions are fastened together by fasteners such as bolts 16 (only two of which are labelled, for clarity) received in apertures 44 of first clamp portion 12 and second clamp portion 14. In the illustrated embodiments, the apertures 44 are evenly spaced along the respective clamp portions, but it will be appreciated that this need not be the case. The bolts 16 may be formed from a metallic material or a composite material, for example. Other types of fasteners are also possible depending on the particular application and the load transfer properties which are desired. Fasteners need not (only) be received in apertures 44. For example, brackets or other like members may be secured around the outer surfaces of clamp portions 12 and 14 to secure them together, and the flanges 26, 28 omitted if so desired. Other possible fastening means include ratchet straps, cable ties, lashing and the like which are cast around the clamp portions 12, 14 and then tightened to fasten them together.

Each clamp portion 12, 14 is formed of a polymer-based composite material. In certain embodiments the composite material comprises a resin matrix (such as a vinyl ester or epoxy matrix), with a fibre material, such as a glass fibre or a carbon fibre, as the reinforcing material. In some embodiments the reinforcing material may be at least partly metallic, provided any metallic components are embedded, such that the clamp portions 12, 14 remain corrosion-resistant. The composite is preferably a light-weight composite. Advantageously, by forming the clamp portions from a polymer-based composite, embodiments of the invention provide a customisable repair apparatus which is readily and rapidly able to be designed and fabricated to carry out repairs on damaged or worn sections of pipeline, without interrupting operation of the pipeline. In particular, the clamp portions can be manufactured using a wide variety of processes, each of which are far quicker to implement than those used to manufacture metal clamps. This reduces the cost and complexity of repair, and also reduces the delay between identification of damage/wear and implementation of the repair.

The use of a fibre-reinforced polymer-based composite is particularly advantageous because the clamp components may be made substantially lighter than metal clamps, whilst providing equivalent strength. Accordingly, structures can be reliably repaired without adding excessive loads, as would not be the case with metal components.

In addition, much greater flexibility of design is provided. The polymer-based composite material and/or the geometry of the clamp components may be readily customised to suit various pipe geometries (straight or curved), pressure requirements and environmental conditions. Fibre types and density/placement can also be tailored to optimise the design in terms of weight, strength and/or cost. The reinforcing fibres may be 2D or 3D fibres, and may be a woven or knitted fabric and/or a stitched or integrally woven preform. Further, unlike metal clamps, polymer-based composite (including fibre-reinforced composite) clamp components are corrosion-resistant and thus well suited not only to above-ground applications but also to buried or harsh ocean environments, for example.

Further structural details of the first clamp portion 12 is shown in Figures 3 and 4. In the embodiment shown in Figures 1 to 4, the second clamp portion 14 is identical in construction to first clamp portion 12 (but need not be, as mentioned above).

First clamp portion 12 has a pair of flanges 26 and 28 extending longitudinally between its ends 22 and 24. The flanges 26, 28 lie either side of a half-cylindrical channel 46. The apertures 44 for receiving fasteners 16 are formed in the flanges 26, 28.

A seal member 30 is seated in a series of grooves against an internal surface 42 of clamp portion 12 and under optional lips 27, 29 which protrude into the channel 46.

Alternative methods of applying the seal 30 to internal surface 42 are also possible. For example, instead of seating in a series of grooves, seal member 30 may be adhered or fused directly to internal surface 42. As a yet further alternative, the seal member 30 may be seated in at least one groove, and additionally adhered or fused to the surface 42.

The grooves may be formed at the same time, in the same manufacturing process, as forming the clamp portions 12 and 14. Alternatively, they may be machined into the clamp portions 12, 14 after the clamp portions have been formed. Seating of the seal member 30 in grooves of the internal surface 42 assists in resisting forces produced by build-up of internal pressure in the pipe 20. This resistance is enhanced by lips 27, 29 against which the edges 34 of seal member 30 abut.

Seal member 30 has a pair of opposed end portions 32, between which extend a pair of opposed side portions 34. The end portions 32 are located within grooves near the ends 22, 24 of the clamp portion 12. The side portions 34 are located within grooves underneath lips 27, 29.

During installation with a pipe 20, a clamp portion 12 is placed underneath the pipe and a second like clamp portion 14 is placed above the pipe. The clamp portions 12, 14 are brought into engagement such that flanges 26 and 28 of clamp portion 12 mate with corresponding flanges of the second clamp portion 14 and the two clamp portions 12, 14 are then fastened together using fasteners 16 as previously described. When the clamp portions 12 and 14 are assembled and fastened around a pipe 20 as shown in Figure 1, the ends 32 and the sides 34 of the seal members 30 are held firmly against the surface of the pipe 20, thereby providing a leak-tight and pressure-tight seal in the region enclosed by the clamp.

Referring now to Figure 5, there is shown an alternative clamp portion 50 for a clamp according to another embodiment of the invention. The clamp portion 50, similarly to clamp portion 12, has a pair of flanges 56 and 58 extending longitudinally between its ends 52 and 54. The flanges 56, 58 lie either side of a half-cylindrical channel 76. When the clamp portion50 is assembled together with another like clamp, a cylindrical channel is therefore formed between the clamp portions for receiving and enclosing a pipe. Apertures 74 for receiving fasteners 16 are formed in the flanges 56, 58.

Seated within clamp portion 50 is a seal member 60 having a pair of opposed end portions 62 which are seated in grooves in the internal surface 76, near respective ends 52 and 54 of the clamp portion 50. A pair of opposed side portions 64 extends between end portions 62. The side portions 64 are seated inside grooves 78 and 80 of flanges 56 and 58 respectively. The seal member 60 may be formed as a unitary component. Alternatively, strips of material 62 can be fused/joined/brought in contact to strips 64 to form the seal member 60.

Opposed end sections 68, 70 of each end portion 62, located at the junctions with side portions 64, protrude above the flanges 56 and 58. Accordingly, when the flanges 56 and 58 of clamp portion 50 are brought into alignment with those of a second like clamp portion around a pipe 20, the side portions 64 of the first clamp portion 50 will contact the corresponding side portions of the second clamp portion, while the end portions 62 will seal against the pipe. Protrusions 68 and 70 of clamp portion 50 will abut corresponding protrusions on the second clamp portion to form a continuous seal around the circumference of the pipe 20.

The seal members 30, 60 are each formed of a resilient material, such as a rubber or other elastomeric or polymeric material.

As shown in Figures 3 to 5, the seal members 30, 60 cover only part of the respective internal surfaces 42, 72 of the clamp portions 12 or 50. In alternative embodiments, one or both of the seal members 30, 60 may be a sheet-like member which covers substantially the entirety of one or both surfaces 42, 72.

In other embodiments, the seal members 30, 60 may comprise, or may be supplemented by one or more resilient patches. Each patch may be positioned on the surface 42 or the surface 72 at a location such that it can abut against a pipe at a location of a leak. One such embodiment is illustrated in Figures 11 and 12, which show repair of a hole 22 in a pipe section 20. A clamp 400 having a lower clamp portion 412 and an upper clamp portion 414 is positioned around the pipe 20, with a resilient patch 420 on the surface of upper clamp portion 414 positioned over the hole 22 as shown in Figure 12. Fastener holes in the flanges of clamp portions 412 and 414 are omitted for clarity. The resilient patch 420 may be seated in a recess in the surface of clamp portion 414 or may be adhered or fused to it. The resilient patch 420 may be provided on its own to form a seal over the damaged portion of the pipe 20, or may be provided in conjunction with one or more further like patches which act to seal other damaged or weakened sections when the clamp portions 412, 414 are fastened together. Any such patches may also be provided in conjunction with seal members 30, 60 to additionally provide a

circumferential seal around the pipe 20 as described above.

In further embodiments, the side portions 34 and/or 64 may extend outwardly so as to cover part or all of flanges 26, 28 and/or flanges 56, 58. In such embodiments, that part of the side portion(s) covering the flanges may have formed therein holes which match the locations of holes 44 and/or 74. The holes may be formed when forming the seal members 30, 60, or may be formed just prior to or during installation, for example by puncturing the seal members (by drilling or by any other suitable means) while the first and second clamp portions 12, 14 are in position on the pipe 20. While in the above embodiments a seal member 30 or 60 has been provided on each of the two clamp portions, in other embodiments it may be possible to provide a seal member on only one of the clamp portions, and still achieve the desired leak/pressure sealing. For example, the embodiment shown in Figures 1 to 4 may be modified such that a seal member 30 is provided either on first clamp portion 12 or second clamp portion 14, but not on both. This may provide several advantages including that less material is used, that the clamp is easier to assemble, and that the clamp is easier to manufacture since seal-related features only need be present on one portion of the clamp.

In yet further embodiments, the surface 42 and/or the surface 72 may carry grout (for example, a cementitious grout, or a non-cementitious grout such as an epoxy resin or polyurethane) which is contactable with the surface of pipe 20. The grout may be applied before installation or may be injected into the channel 46, 76 in situ. The grout is cured, or allowed to cure, thereby forming a strengthening layer on the pipe 20. Accordingly, the clamp in these embodiments provides both leak/pressure containment and strengthening of the pipe, which can be particularly advantageous for pipes which have thinned due to erosion/corrosion. Clamp portion 12 and/or clamp portion 14 may have one or more inlet holes to facilitate injection of grout and to allow testing of the seal once the clamp 10 is installed. Either or both of the clamp portions may also have one or more venting holes to allow air to be forced out of the channel 46, 76 when the grout is injected. Not shown in the Figures, but useful during the installation process, are optional lifting lugs located on the surface of clamp portion 12 and/or clamp portion 14. The lifting lugs are preferably formed integrally with the respective clamp portions during manufacture of the clamp portions. Turning now to Figure 6, an alternative embodiment of a clamp 1 10 is shown. The clamp 1 10 includes a first clamp portion 1 12 and a second clamp portion 1 14 fastened around a pipeline at a bend between two straight sections of pipe 120 and 122. Each clamp portion 1 12, 1 14 is formed as a single component, having a bend which matches the bend in the pipeline. The internal configuration of each clamp portion 112, 1 14 is similar to the internal configuration of clamp portions 12, 14. The clamp portions 112 and 1 14 may be fastened together in any suitable fashion, for example by providing through-holes (not shown) in the flanges of each clamp portion to receive fasteners.

In a yet further embodiment, shown in Figures 7 to 9, a clamp 200 assembled and fastened on pipe 20 (Figure 8) includes a first clamp portion 212 and a second clamp portion 214. The internal configuration of clamp portions 212 and 214 may be identical to that of clamp portions 12 and 14, or clamp portion 50, for example. The clamp 200 of Figures 7 to 9 comprises a hinge 216 joining the clamp portions 212 and 214 along one edge, such that the clamp portions 212 and 214 need only be fastened together along the other edge, by fasteners received in through-holes 244 (only one of which is labelled on each clamp portion for clarity), once the clamp 200 is in place. If so desired then the clamp portions 212, 214 may also be fastened along the hinge side of the clamp, such that the hinge 216 chiefly assists in locating the clamp on the pipe 20 rather than being a load-bearing structure. The hinge 216 may be manufactured from the same polymer- based composite material as clamp portions 212 and 214. Advantageously, the use of a hinge facilitates installation of the clamp 200 since the relative longitudinal position of clamp portions 212 and 214 is fixed and through-holes 244 are already aligned prior to installation.

In variations of the embodiments of Figures 7 to 9, the clamp may include three or more clamp portions, adjacent pairs of which are joined by respective hinges. In such embodiments, two of the clamp portions may each have a flange with apertures to receive fasteners, such that those clamp portions are fastenable together while the remaining clamp portions are joined by hinges to their two adjacent clamp portions, there being a number of hinges which is one less than the number of clamp portions. An advantage of using three or more clamp portions in this way may be ease of assembly, since the multiply-hinged clamp has greater range of movement (more degrees of freedom) and may be more easily positionable around the pipe to be repaired.

In a yet further embodiment, shown in cross-section in Figure 10, a clamp 300 comprises two clamp portions 312, 314 each of which is formed from a polymer-based composite shell 320 surrounding a core material 322. The constructional details of clamp portions 312, 314 may otherwise be substantially identical to those of clamp portions 12 or 50, for example. The shell 320 may be formed from the same type of polymer-based composite as used to form clamp portions 12, 14, or 50. The core 322 may be formed using a variety of materials, including but not limited to: a closed-cell polymer foam; a syntactic foam; or a metal, composite or graphite honeycomb material. The composite clamp portions 12, 14, 50, 212, 214, 312, 314, 412, 414 can be manufactured by a number of different methods. Exemplary methods include, without limitation: resin vacuum infusion, filament winding, pre-preg processes (typically followed by heating to complete polymerisation), wet layup processes, and resin transfer moulding.

Embodiments of the invention provide one or more of the following advantages:

• Allows rapid online repair of pipelines/risers;

• Customised repairs that can be manufactured quickly and cost-effectively for both straight pipes and bends;

• Corrosion resistant and does not add excessive loads to repaired structures;

• Lightweight;

• Allows quick manufacture and installation for various shapes;

• Saves cost in terms of installation time;

• Quick underwater, above-water and buried application;

• Customisable geometries for straight pipes and bends/flanges. Although particular embodiments of the invention have been described in detail, many modifications and variations are possible within the scope of the invention, as will be clear to a skilled reader.

It should be appreciated that the various features of the embodiments that have been described may be combined in various ways to produce numerous additional embodiments. Moreover, while various materials, dimensions, shapes, configurations and locations, etc. have been described for use with disclosed embodiments, others besides those disclosed may be utilised whilst still falling within the scope of the invention.

Claims

A clamp for repairing a section of pipeline, the clamp comprising:

a plurality of clamp portions; and

A clamp according to claim 1 , wherein two or more of the clamp portions each comprise at least one flange , the clamp being fastenable in place on the pipeline section by securing respective flanges of the respective clamp portions.

A clamp according to claim 2, wherein the flanges each have at least one aperture formed therein, a fastener being receivable in said aperture to secure respective flanges together.

A clamp according to any one of the preceding claims, comprising a seal member disposed on an internal surface of each clamp portion.

A clamp according to claim 4, wherein the seal members are configured to cooperate to collectively form a circumferential seal around the pipeline section.

A clamp according to claim 4 or claim 5, wherein each seal member comprises first and second opposed end portions, and first and second opposed side portions extending between the first and second end portions.

7. A clamp according to any one of claims 4 to 6, wherein at least one seal member covers the internal surface of the clamp portion on which it is disposed.

8. A clamp according to claim 6 or claim 7, wherein respective end portions of adjacent pairs of the seal members are configured to abut against each other, such that the end portions collectively form continuous seals around a circumference of the pipe.

9. A clamp according to any one of the preceding claims, wherein the clamp portions are identical to each other.

10. A clamp according to any one of the preceding claims, wherein at least one pair of clamp portions is joined by a hinge.

1 1. A clamp according to any one of the preceding claims, wherein at least one of the clamp portions is formed from a polymer-based composite shell surrounding a core material.

12. A clamp according to claim 1 1, wherein the core material is selected from the group comprising: a closed-cell polymer foam; a syntactic foam; or a metal, composite or graphite honeycomb material.

13. A clamp according to any one of the preceding claims, wherein the polymer-based composite material comprises a fibre-reinforced polymer.

14. A clamp according to any one of the preceding claims, wherein at least one clamp portion is internally and/or externally lined or coated with a chemical-resistant and/or fire-resistant and/or low-permeability material.

15. A clamp according to any one of the preceding claims, comprising two clamp

portions.

16. A method of repairing a section of pipeline, the method comprising:

providing a clamp according to any one of claims 1 to 14;

positioning the clamp portions around the section of pipeline; and securing the clamp portions to each other;

whereby the plurality of clamp portions and the seal cooperate to enclose the pipeline section in a channel therebetween, with the seal bearing against a surface of the pipeline section.

17. A method according to claim 16, further comprising applying grout to an internal surface of at least one of the clamp portions.

18. A method according to claim 17, wherein the grout is applied by injection into the channel.

19. A method according to claim 17 or claim 18, comprising applying grout in an

annular region bounded by the pipe and the clamp.

20. A method according to any one of claims 16 to 19, further comprising applying at least one layer of a fibre or adhesive tape material to a weakened or damaged region of the section of pipeline prior to securing the clamp portions to each other.

21. A method of manufacturing a clamp for repairing a section of pipeline, comprising: forming a plurality of clamp portions, the clamp portions each comprising a polymer-based composite material; and

22. A method according to claim 21 , comprising surveying said pipeline; and based on the results of said surveying, forming said clamp portions.

23. A method according to claim 21 or claim 22, wherein the clamp portions are formed by one or more of: resin vacuum infusion, filament winding, a pre-preg process, a wet layup process, or resin transfer moulding.

24. A method according to any one of claims 21 to 23, wherein the polymer-based composite material comprises a fibre-reinforced polymer.