High-stiffness cables and their use

Abstract

Cable (1) of high stiffness, with a cable core (2.1, 2.2) and a stranded assembly encasing it, forming an armor (3), wherein the armor (3) is composed of at least one stranding layer of two groups of stranding wires of different cross-sections arranged alternately around the circumference of the cable (1) with mutually complementary contact surfaces (4, 5), wherein the stranding wires have an arc-shaped profile cross-section which is based on the basic geometry of a sector profile of a circular ring, and wherein - a group of stranding wires is formed by first profile wires (6), which first profile wires (6) have at least one longitudinal web (7) extending along the profile wire (6) on both sides of the sector profile in the area of ​​their contact surfaces (4), whereas - the other group of stranded wires is formed by second profile wires (8), which second profile wires (8) have longitudinal grooves (9) in the area of ​​their contact surfaces (5) that correspond to said longitudinal webs (7) of the immediately adjacent first profile wires (6) and each of which receives a longitudinal web (7) in a form-fitting manner, characterized in that the cable core (2.1, 2.2) is axially fixedly connected to the reinforcement (3) by a form-fit and / or force-fit, wherein the form-fit and / or force-fit is effected by means of at least one projection (22.1, 22.2), which projection (22.1, 22.2) is formed on a contact surface (23) of at least one profile wire (6, 8) facing the cable core (2.1, 2.2) and penetrates the surface of the cable core (2.1, 2.2) in a form-fit manner, or at least against the surface of the Cable core (2.1, 2.2) is pressed / is pressed.

Description

[0001] The invention relates to a cable of high stiffness, in particular high axial stiffness, according to the preamble of claim 1 of the invention.

[0002] In order to obtain usable information about the presence and yield as well as possibilities for the development of oil and natural gas deposits, geophysical measurements are carried out using a cable and associated measuring heads or probes in vertical and partly also in horizontally inclined boreholes of great length.

[0003] Geophysical measurements are carried out both at the open borehole and after lowering a production pipe under production conditions, or at the closed borehole. The measuring heads or probes are either lowered along the measuring cable or are positioned at a distal end of the cable before it is inserted into the borehole. This, however, requires that the measuring and exploration cables and associated measuring equipment are designed to withstand the pressures, temperatures, and humidity levels inherent in the depths.

[0004] To ensure cable insertion, particularly into horizontally drilled boreholes, axial force application is required due to the contact between the measuring and exploration cable and the borehole wall. This force must overcome the frictional and braking resistances caused by this contact. This can only be achieved with a cable capable of withstanding sufficient thrust forces.

[0005] In the prior art, measuring and exploration cables are known whose core is enclosed by an armor consisting of two layers of high-strength steel wires, in particular round wires, with a diameter of 0.8 to 1.3 millimeters. These cables can only withstand tensile forces. Furthermore, the round wires used for the armor must be stretched to achieve a uniform fit and alignment around the circumference of the cable. Moreover, cables of this type cannot effectively prevent the ingress of potentially aggressive media, such as fluids or solids. The water that cannot escape from the armor increases the risk of corrosion or deterioration of the cable core.In summary, it can be stated that such measuring and exploration cables are not suitable for greater depths and for measuring long horizontal boreholes with a slight inclination due to insufficient axial stiffness and their non-media-tight sealed reinforcement.

[0006] To address the aforementioned disadvantage, DE 38 08 049 A1 describes a single- or multi-core electrical cable, in particular a borehole or shaft cable, which consists of reinforcement arranged over a core and an overlying sheath. Specifically, the borehole or shaft cable comprises a multitude of individual wires surrounded by insulation, e.g., made of PE (PE = polyethylene). The reinforcement consists of helically wound plastic strands surrounding the insulation. These plastic strands enclose a sheath, e.g., made of PP (PP = polypropylene), in which high-tensile-strength threads or yarns extend longitudinally. To achieve sufficient arch strength, the plastic strands can have a Z-shaped cross-section.Furthermore, the high-tensile threads or yarns can also be arranged in a PP strand, which has a groove on one side and a tongue on the other. This tongue and groove connects the strand to adjacent strands, forming the reinforcement. This is intended to improve the lateral compressive strength of the reinforcement. A further layer of coiled metal wires, such as round wires, wire mesh, or a corrugated metal sheath, is applied over the layer of plastic strands. This additional layer is encased in a sheath of abrasion-resistant plastic.

[0007] DE 10 2004 015 219 A1 describes a cable for geophysical measurement and exploration purposes, particularly for use in the oil and gas production industry. This cable has a core comprising several conductors bundled together and insulated from one another, as well as a sheath surrounding the conductor bundle made of glass fibers embedded in plastic. The outer sheath of the cable is constructed of at least one layer of Z-wires, which are laid helically around the sheath over a longer section, namely the lay length of the cable, with adjacent Z-wires interlocking and interlocking with one another.

[0008] US 2008 / 0289849 A1 describes a cable for geophysical measurement and exploration purposes, or a borehole cable, comprising at least one metallic conductor enclosed in an insulating sheath, a layer of inner reinforcing wires surrounding the insulated conductor, and a layer of outer reinforcing wires surrounding the inner reinforcing wires. The inner layer of reinforcing wires may consist of round wires or profile wires. The outer layer may consist of round wires, profile wires, or a combination of round and profile wires. A polymer material is introduced into the spaces between the inner reinforcing wires, the outer reinforcing wires, and the spaces between the inner reinforcing wires and the insulated conductor, with said polymer material encasing and separating the reinforcing wires.

[0009] DE 10 2009 057 147 A1 describes a cable for geophysical measurement and exploration purposes, comprising a cable core and a stranded reinforcement sheathing that encloses the core. The reinforcement consists of at least one stranding layer of two groups of stranded wires of different cross-sections arranged alternately around the circumference of the cable, with complementary contact surfaces. One group of stranded wires consists of round wires, and the other group consists of profiled wires. The profiled wires have an arc-shaped cross-section, which is based on the geometry of a sector profile of an annulus. The contact surfaces of the profiled wires are concave, complementary to the contact surfaces of the adjacent round wires.

[0010] Furthermore, a cable, in particular a submarine cable, and a method for its manufacture are known from DE 100 59 918 A1. In this cable, the core is surrounded by an armor, whereby, if necessary, a number of the armor wires intended to form the armor are replaced by the partial placement of filler strands. To reduce weight, the filler strands are preferably made of plastic. Due to the fact that the cable has armor with varying load-bearing capacities along its longitudinal axis, it is not suitable as a geophysical measurement and exploration cable, as it lacks both sufficient axial stiffness for tensile and compressive forces and a constant axial stiffness along its longitudinal axis.

[0011] DE 38 10 746 C2 further describes a submarine cable with a cable core containing at least one optical fiber and with at least one armored sheath. The cable core enclosed by the armor is completely filled using a multi-layered high-voltage insulating layer. A characteristic feature of this technical solution is that the armor, encased in an outer sheath made of an elastic plastic, is formed from interlocking Z-shaped profile wires, and that an electrical conductor consisting of several segmented wires, surrounding at least the optical fibers in a tubular form, is arranged within the cable core. The use of this submarine cable for geophysical measurement and exploration purposes is precluded due to the large specific diameter resulting from the individual layers.

[0012] From the generic patent FR 2 564 635 A1, a submarine cable or a cable for use in submarines is known, comprising a cable core and a stranded assembly encasing it, forming an armor. The armor consists of at least one stranding layer of two groups of stranding wires of different cross-sections arranged alternately around the circumference of the cable, with complementary contact surfaces. The profile wires have an arc-shaped cross-section, which is based on the basic geometry of a sector profile of a circular ring. The contact surfaces of the profile wires are concave, complementary to the contact surfaces of the adjacent round wires. Furthermore, a group of stranding wires is formed by first profile wires, which each have at least one longitudinal web extending along the profile wire on both sides of the sector profile in the area of ​​their contact surfaces.The other group of stranded wires is formed by second profile wires, which in the area of ​​their contact surfaces each have longitudinal grooves corresponding to said longitudinal webs of the immediately adjacent first profile wires and each receiving a longitudinal web in a form-fitting manner.

[0013] US Patent 5,468,913 A discloses a ship tow cable designed for coaxial data transmission. The tow cable comprises a multitude of round coaxial core conductors bundled in the center of the cable and evenly distributed along its centerline. The core conductors are surrounded by a first extruded layer of dielectric material. Spiral grooves are cut into the outer cylindrical surface of the dielectric layer, extending along its entire length. Fiber optic transmitters are arranged within these spiral grooves. A layer of protective tape is wrapped around the conductor and the fiber optic transmitter assembly, bridging the spiral grooves and the fiber optic transmitters within them, thus securing the transmitters in place. A second layer of dielectric material is extruded over the protective tape.A coaxial shield conductor, a second protective tape layer with a surrounding waterproof material, and an unspecified outer load-bearing armor layer are wrapped around the second dielectric layer to provide external protection to the cable.

[0014] US Patent 5,150,443 A discloses an electrical cable designed to support a borehole probe in a borehole drilled into the earth. The cable comprises a core containing a transmission line for transmitting data and operating commands to and from the probe. The transmission line is housed within a steel tube. The tube is surrounded by a plastic layer. A set of conductive copper wires surrounds the plastic layer. The copper wires are encased in a thermoplastic sheath. An inner armor layer, consisting of numerous pre-formed metal strands wound spirally around the sheath, is wrapped around the inner armor layer. An outer armor layer, consisting of numerous metal strands wound in the opposite direction to the inner metal strands, is wound onto the inner armor layer.An embedding layer is provided for the inner armor strands, positioned between the outer shell and the inner armor layer. This embedding layer consists of an elastic and curable thermosetting material that fills the spaces between the inner armor strands.

[0015] Starting from this premise, the object of the invention is to create a cable with high stiffness, particularly high axial stiffness, that is an alternative to the prior art. According to a first aspect of the invention, this cable is simple and cost-effective to manufacture and can withstand high compressive and tensile forces as well as differential internal pressures without any deformation. According to a second aspect of the invention, the cable should also allow the exploration and measurement of long horizontal boreholes or boreholes with a slight inclination at greater depths. According to a third aspect of the invention, the cable should reliably prevent the passage of fluids, in particular, through its outer sheath.

[0016] Starting from a cable of high axial stiffness, with a cable core and a stranded assembly encasing it and forming an armor, wherein the armor is composed of at least one stranding layer of two groups of stranding wires of different cross-sections arranged alternately around the circumference of the cable with mutually complementary contact surfaces, wherein the stranding wires have an arc-shaped profile cross-section which is based on the basic geometry of a sector profile of a circular ring, and wherein - a group of stranding wires is formed by first profile wires, which first profile wires have at least one longitudinal web extending along the profile wire on both sides of the sector profile in the area of ​​their contact surfaces, whereas - the other group of stranding wires is formed by second profile wires, which second profile wires in the area of ​​their contact surfaces each have longitudinal grooves corresponding to said longitudinal webs of the immediately adjacent first profile wires and each receiving a longitudinal web in a form-fitting manner, the problem is solved by the fact that the cable core is axially fixed to the reinforcement by means of a form-fit and / or force-fit, whereby the form-fit and / or force-fit is effected by means of at least one protrusion, which protrusion is formed on a contact surface of at least one profile wire facing the cable core and penetrates the surface of the cable core in a form-fit manner in a radially inward direction, either directly or indirectly, or at least is pressed against the surface of the cable core.

[0017] This measure ensures a particularly strong bond between the two groups of stranded wires, in the form of the first and second profile wires, in the radial direction, while achieving high axial stiffness of the cable. Extensive tests have shown that the bond is particularly strong and permanent, especially when one profile wire has only longitudinal ribs and the immediately adjacent profile wires have only longitudinal grooves. Furthermore, the complementary, interlocking contact surfaces create a fluid-tight seal. The at least one raised section of the type described above effectively prevents axial movement between the cable core and the reinforcement during the cable's intended use, particularly as a geophysical measurement and exploration cable in long boreholes.

[0018] The dependent claims describe preferred further developments or embodiments of the invention.

[0019] To facilitate the production of the reinforcement, in particular the interlocking of the profile wires, the longitudinal webs of each first profile wire are designed to taper towards their free ends when viewed in cross-section. During the reinforcement production process, these webs preferably engage in longitudinally shaped grooves of complementary form. The longitudinal webs can be tapered, trapezoidal, or convexly rounded in cross-section. An equivalent, or at least a similar, effect can be achieved if at least the free ends of the longitudinal webs are trapezoidal, convexly rounded, or tapered in cross-section.In a further development of the invention, an interference fit (press fit) can be achieved by a specific design of the longitudinal webs in relation to the longitudinal grooves that receive them in a form-fitting manner, thereby advantageously combining a form-fit with a force-fit. This further increases the strength of the reinforcement composite as well as the fluid tightness of the cable.

[0020] As for the cable core, depending on the chosen application, it can advantageously have a solid cross-section or, alternatively, a tubular cross-section. The axial and radial stability of the cable is essentially achieved by the specially designed armoring described above.

[0021] As further provided by the invention, the cable core comprises at least one electrical conductor and / or signal conductor. Advantageously, the cable core can also comprise one or more conductors or conductor bundles, which are formed, for example, by electrical and / or signal conductors, wherein optical fibers, and more preferably optical fibers made of a temperature-resistant fiberglass, are used as signal conductors. Advantageously, said conductors or conductor bundles can themselves be enclosed in a media-tight sheath to protect them directly from various environmental influences. With regard to the aforementioned solid cross-section of the cable core, the electrical conductors or signal conductors are preferably embedded within it. If, on the other hand, a cable core with a tubular cross-section is preferred, one or more conductors are preferably embedded within the tubular cross-section and / or arranged in the cavity formed by the tubular cable core.As further provided by the invention, the cable core comprises at least one means for electromagnetic shielding of the at least one electrical conductor and / or signal conductor. The at least one means for electromagnetic shielding is preferably formed by a ribbon-shaped or tubular metal mesh and / or by a ribbon-shaped or tubular metal foil.

[0022] To more effectively prevent axial relative movement between the cable core and the armor during the intended use of the cable, particularly as a geophysical measurement and exploration cable in long boreholes, the cable core is additionally bonded to the armor by a material bond. This material bond is preferably achieved using an adhesive, which is preferably applied to the cable core and cures after the cable core is sheathed with the armor or the stranding wires are wound onto the cable core. Advantageously, the adhesive also acts as a sealant by filling any remaining voids between the profile wires of the cable armor and between the profile wires and the cable core, thus ensuring a particularly high fluid tightness of the cable.

[0023] Regarding the aforementioned positive and / or force-fit connection between the cable armor and the cable core by means of the at least one projection, the projection can extend along the profile wire, thereby winding helically around the cable core and thus preventing, or at least effectively hindering, axial relative movement between the cable armor and the cable core. Alternatively, the at least one projection can also extend transversely to the longitudinal extent of the profile wire. If several such projections are provided, a contact surface with the cable core is formed, which, like a rack, has at least partially alternating projections or teeth and gaps. These teeth engage the surface of the cable core in a positive-fit manner, or at least are pressed against the surface, thus preventing, or at least effectively hindering, the aforementioned axial relative movement.Preferably, the profile wires are made of a steel that is suitable for withstanding high and extremely high forces acting on the cable, for example, when used for geophysical measurement and exploration purposes, particularly in the oil and gas production industry. In this respect, said at least one raised section is preferably formed during the production of the at least one profile wire by a rolling process.

[0024] To achieve a high-quality layer structure of the stranded reinforcement, the profile wires, especially those made of steel, are stranded without twisting and placed in the stranded reinforcement without tension, by pre-forming the profile wires using pre-forming devices known per se.

[0025] As already mentioned, the cable described above is advantageously suited for geophysical measurement and exploration purposes, particularly in the oil and gas production industry. However, it can also be used as a submarine cable or as any other type of cable with one or more electrical and / or signal conductors, such as an underground cable.

[0026] The invention is explained in more detail below with reference to the exemplary embodiments schematically illustrated in the drawings. However, it is not limited to these embodiments, but encompasses all embodiments defined by the claims. The drawings show: Fig. 1 a cross-sectional representation of a cable of the generic type according to a first embodiment variant, Fig. 2 a cross-sectional representation of a generic cable according to a second design variant, Fig. 3a - 3d the details “Z1” to “Z4” after Fig. 1 with a detailed representation of the cable's profile wires in four different design variants, and Fig. 4a, Fig. 4b The details of “Y1” and “Y2” according to Fig. 2 with two further embodiment variants of the said profile wires according to the invention. Embodiments not covered by the invention (Figs. 1-3d):

[0027] The Fig. 1 and Fig. Figures 2 each show a cross-section of a cable 1 with a highly schematic cable core 2.1, 2.2, which is in turn encased by a stranded structure forming an armor 3. The armor 3 consists of two groups of stranded wires of different cross-sections arranged alternately around the circumference of the cable 1, with contact surfaces 4, 5 that are complementary in shape to each other. The stranded wires of both groups have an arc-shaped profile cross-section, which is based on the basic geometry of a sector profile of a circular ring.

[0028] One group of stranding wires is formed by first profile wires 6, each of which has a longitudinal web 7 extending along the length of the first profile wire 6 on both sides of the aforementioned sector profile in the area of ​​its contact surfaces 4. Also included are two or more longitudinal webs 7 arranged one above the other in the radial direction of the cable 1, at least in the area of ​​one of the aforementioned contact surfaces 4 (not shown in the drawing). The other group of stranding wires, in contrast, is formed by second profile wires 8, each of which has longitudinal grooves 9 corresponding to the aforementioned longitudinal webs 7 of the immediately adjacent first profile wires 6 in the area of ​​its contact surfaces 5, and each groove receiving a longitudinal web 7 in a form-fitting manner.

[0029] Preferably, the profile wires 6, 8 are made of a steel that is suitable for transmitting high and extremely high forces acting on the cable 1. For example, when the cable is used for geophysical measurement and exploration purposes, particularly in the oil and gas production industry, especially high axial compressive and tensile forces must be transmitted due to the long borehole lengths of up to 8,000 m. Furthermore, at great depths, particularly in offshore operations, high differential internal pressures occur within the cable 1, which the reinforcement 3 must withstand without deformation and while ensuring a high fluid tightness in the radial and transverse directions of the cable 1.

[0030] According to the Fig. 1, Fig. 2 and Fig. 3a The longitudinal webs 7 and the longitudinal grooves 9, which are shaped to complement them, have a rectangular or square cross-section. This means that the radially inward and radially outward facing surfaces of the longitudinal webs 7 extend on a normal to the radius of the cable 1. This results in a high resistance of the profile wires 6, 8 to radial disintegration of the reinforcement 3, particularly under high internal pressures of the cable 1.

[0031] To facilitate the production of the reinforcement 3, in particular the stranding of the first and second profile wires 6, 8 with a positive fit to one another, it is provided that the longitudinal webs 7 of the first profile wires 6, viewed in cross-section of each first profile wire 6, are designed to taper towards their free end. This measure allows the longitudinal webs 7 to be easily inserted into the respective, preferably form-complementary, longitudinal groove 9 during the production of the reinforcement 3. The longitudinal webs 7 are preferably trapezoidal in cross-section ( Fig. 3b) or convexly rounded ( Fig. 3c). It is also conceivable to provide a tapered cross-section for the longitudinal webs 7 (not shown in the drawing).

[0032] An equivalent, or at least a similar, effect can be achieved if at least the free ends of the longitudinal webs 7 are trapezoidal in cross-section (cf. Fig. 3d) or are formed with convex rounding or a pointed shape (not shown in the drawing). This measure has the advantage that, while ensuring high resistance of the profile wires 6, 8 to radial disintegration of the reinforcement 3, the joining of the profile wires 6, 8 to each other is also simplified. Each longitudinal web 7 has a first, profile-side section 7a with surfaces facing radially inwards and radially outwards, which lie on a normal to the radius of the cable 1, wherein at least one of the aforementioned first sections 7a transitions into a second, free end section 7b, which is inclined such that the cross-section of the longitudinal web 7 tapers in this end section 7b.

[0033] By specifically designing the longitudinal webs 7 in relation to the longitudinal grooves 9 that receive them in a form-fitting manner, an interference fit (press fit) can be achieved, advantageously combining a form-fit with a force-fit (not shown in the drawing). This further increases the strength of the reinforcement 3 composite and the fluid tightness of the cable 1.

[0034] Depending on the chosen application of cable 1, the cable core 2.1, 2.2 can be configured according to Fig. 1 a solid cross-section or alternatively according to Fig. 2 have a pipe cross-section. The axial and radial stability and stiffness of the cable 1 are essentially achieved by the specially designed reinforcement 3 described above.

[0035] The cable core 2.1 with solid cross-section exhibits, according to the in Fig. In the embodiment of the invention shown in Figure 1, an electrical conductor 10, in particular a copper conductor, is shown by way of example only, which is located in the Fig. The electrical conductor 10 is characterized by a dashed line. It is covered by, or embedded in, a sheath 11 made of a synthetic polymer. This sheath 11 is preferably applied to the electrical conductor 10 using a known extrusion process.

[0036] Instead of the aforementioned electrical conductor 10, a signal conductor (not shown in the drawing), for example in the form of an optical fiber made of a preferably temperature-resistant fiberglass, can also be provided. Advantageously, the cable core 2.1 can also have one or more conductor bundles, which are formed, for example, by electrical conductors 10 and / or signal conductors, such as optical fibers (not shown in the drawing). Advantageously, the electrical conductors 10 or signal conductors or conductor bundles themselves can be enclosed in a media-tight sheath and then covered by the aforementioned sheath 11 (not shown in the drawing).

[0037] The cable core 2.1 comprises a means 12 for electromagnetic shielding of the single electrical conductor 10, which is shown by way of example. The means 12 for electromagnetic shielding is preferably formed by a ribbon-shaped or tubular metal mesh and / or by a ribbon-shaped or tubular metal foil, which is not shown in detail but is known per se. The metal mesh or metal strip preferably consists of copper or a copper alloy. The means 12 for electromagnetic shielding, or the metal mesh or metal foil, is applied to the outer sheath surface 13 of the sheath 11 as shown, for example, wound or braided onto the sheath 11 as a strip or pulled onto the sheath 11 as a tube.

[0038] In contrast, the electromagnetic shielding agent 12, i.e., the metal mesh or metal foil, can be embedded in the sheath 11 or formed integrally with it. In this case, the electromagnetic shielding agent 12, i.e., the metal mesh or metal foil, functions as an insert, being continuously embedded in the extrusion mass of the sheath 11 during its production using the aforementioned extrusion process (not shown in the drawing).

[0039] The cable core 2.2 according to Fig. 2, unlike cable core 2.1, shows Fig. 1. A pipe cross-section. The said pipe cross-section is preferably formed by a prefabricated elongated pipe 14 made of a synthetic polymer. Such a pipe 14 is preferably produced by an extrusion process known per se. In the present case, only by way of example, two electrical conductors 10 (dashed lines) are embedded in the said pipe cross-section of the pipe 14 or in its pipe wall. Moreover, in Fig. Figure 2 shows, also only as an example, a conductor bundle 15 with three electrically insulated conductors 10, which conductor bundle 15 is arranged relatively freely in the cavity 16 formed in the tubular cable core 2.2. The conductor bundle 15 is itself encased by protective insulation 17.

[0040] Based on the embodiment of cable 1 according to Fig. The tubular cable core 2.2 also includes an electromagnetic shielding means 18, preferably in the form of a known band-shaped or tubular metal mesh and / or in the form of a band-shaped or tubular metal foil. The electromagnetic shielding means 18 is applied to the outer sheath surface 19 of the tube 14, in particular by being wound, braided, or drawn on. Furthermore, the tube 14, including the electromagnetic shielding means 18, is covered by a sheath 20 made of a synthetic polymer. The sheath 20 is preferably applied by a known extrusion process such that the electromagnetic shielding means 18 is embedded in the extruded material of the sheath 20.Preferably, the tube 14 and the jacket 20 consist of a chemically identical or largely identical material, so that they form a chemical bond and thus create a homogeneous material composite.

[0041] The synthetic polymer used to form both the sheath 20 of the cable core 2.1 and the tube 14 and sheath 20 of the cable core 2.2 is preferably ETFE (ETFE = ethylene tetrafluoroethylene). ETFE advantageously combines high temperature resistance (up to 150°C) with good resistance to aggressive media, such as acids, aromatic hydrocarbons, etc. Furthermore, ETFE advantageously has a low weight and is particularly suitable for use as an electrical insulator.

[0042] In order to effectively prevent axial relative movement between the cable core 2.1, 2.2 and the armor 3 during the intended use of the cable 1, in particular as a geophysical measuring and exploration cable in long boreholes, the cable core 2.1, 2.2 is axially firmly connected to the armor 3 by material, form and / or force connection.

[0043] According to the Fig. 1 and Fig. 2. The aforementioned material bond is preferably achieved by means of an adhesive 21, which is applied to the cable core 2.1, 2.2 and sets or hardens after the cable core 2.1, 2.2 is sheathed with the armor 3 or the stranding wires or profile wires 6, 8 are wound onto the cable core 2.1, 2.2. Advantageously, the adhesive also acts as a sealant by filling any remaining voids between the profile wires 6, 8 of the armor 3 of the cable 1 and between the profile wires 6, 8 and the cable core 2.1, 2.2, thereby ensuring a particularly high fluid tightness of the cable 1. The adhesive 21 preferably consists of a suitable synthetic polymer. Exemplary embodiments of the invention (Figs. 4a and 4b):

[0044] Regarding the aforementioned form-fit and / or force-fit between the armor 3 of the cable 1 and the cable core 2.1, 2.2, this is effected by means of at least one projection 22.1, 22.2 on a contact surface 23 of at least one profile wire 6, 8 facing the cable core 2.1, 2.2. The at least one projection 22.1, 22.2 is, as shown in the Fig. 4a and Fig. 4b is shown by way of example, starting from said contact surface 23 directed radially inwards, whereby it penetrates the surface of the cable core 2.1, 2.2 in a form-fitting manner during the stranding process, or at least is pressed against the surface of the cable core 2.1, 2.2 and thus prevents, or at least effectively hinders, an axial relative movement between the armoring 3 and the cable core 2.1, 2.2.

[0045] Fig. Figure 4a shows, in addition to the material-bonded joining connection, a form-fit joining connection with, by way of example, a protrusion 22.1 on each of the profile wires 6, 8. The protrusions 22.1 extend along the respective profile wire 6, 8. Due to the stranding, the protrusions 22.1 coil helically around, for example, the cable core 2.2 and thereby penetrate its surface in a form-fit manner. This prevents, or at least effectively hinders, axial relative movement between the profile wires 6, 8 or the reinforcement 3 and the cable core 2.2.

[0046] Fig.Figure 4b shows an alternative positive-locking connection between the reinforcement 3 and the cable core 2.2. Essentially, one or more projections 22.2 extending transversely to the longitudinal extent of each profile wire 6, 8 are provided. If several such projections 22.2 are provided for each profile wire 6, 8 (not shown in the drawing), a contact surface 23 is formed with the cable core 2.2, which, like a rack, has alternating projections 22.2, so to speak, and gaps, at least in sections. The teeth engage positively with the surface of the cable core 2.2, thereby preventing, or at least effectively hindering, axial relative movement between the profile wires 6, 8 or the reinforcement 3 and the cable core 2.2.

[0047] As already explained above, the profile wires 6, 8 preferably consist of a steel that is suitable for withstanding high and extremely high forces acting on the cable 1, for example, when the cable is used for geophysical measurement and exploration purposes, particularly in the oil and gas production industry. In this respect, said at least one raised section 22.1, 22.2 is preferably formed during the production of the at least one profile wire 6, 8 by a rolling process on the profile wire 6, 8.

[0048] To achieve a high-quality layer structure of the stranded bond forming the reinforcement 3, the profile wires 6, 8, made of steel in particular, are stranded without twisting and placed in the stranded bond without tension by means of pre-forming devices known per se.

[0049] The foregoing embodiments refer to a cable 1 with a cable core 2.1, 2.2 and an armor 3 sheathing the cable core 2.1, 2.2, which armor 3 is formed "merely" by a stranding layer of the type described above. However, the invention is not limited to these embodiments, but also encompasses cables 1 of the generic type with an armor 3 formed by a plurality of layers, wherein at least one, but preferably several, of said stranding layers are formed by profile wires 6, 8 of the type described above (not shown in the drawing). Reference symbol list 1 cable 2.1 Cable core 2.2 Cable core 3 Reinforcement 4 contact surfaces (first profile wires 6) 5 contact surfaces (second profile wires 8) 6 first profile wires 7 Longitudinal web 7a first section 7b second section 8 second profile wires 9 longitudinal groove 10 electrical conductors 11 coat 12 means of electromagnetic shielding 13 Outer surface area (shell 11) 14 pipe 15 bundles of conductors 16 Cavity 17 Protective insulation (conductor bundle 15) 18 means of electromagnetic shielding 19 Outer shell surface (pipe 14) 20 coats 21 Adhesive 22.1 Survey 22.2 Survey 23 Contact area

Claims

[1] Cable (1) of high stiffness, comprising a cable core (2.1, 2.2) and a stranded assembly enclosing the same forming an armor (3), wherein the armor (3) is composed of at least one stranding layer of two groups of stranding wires of different cross-sections arranged alternately around the circumference of the cable (1) with mutually complementary contact surfaces (4, 5), wherein the stranding wires have an arc-shaped profile cross-section which is based on the basic geometry of a sector profile of a circular ring, and wherein - a group of stranding wires is formed by first profile wires (6), which first profile wires (6) have at least one longitudinal web (7) extending along the profile wire (6) on both sides of the sector profile in the area of ​​their contact surfaces (4), whereas - the other group of stranding wires is formed by second profile wires (8), which second profile wires (8) have longitudinal grooves (9) in the area of ​​their contact surfaces (5) corresponding to said longitudinal webs (7) of the immediately adjacent first profile wires (6) and each receiving a longitudinal web (7) in a form-fitting manner, characterized by , that the cable core (2.1, 2.2) is axially fixedly connected to the reinforcement (3) by means of a form-fit and / or force-fit, wherein the form-fit and / or force-fit is effected by means of at least one projection (22.1, 22.2), which projection (22.1, 22.2) is formed on a contact surface (23) of at least one profile wire (6, 8) facing the cable core (2.1, 2.2) and penetrates the surface of the cable core (2.1, 2.2) in a form-fit manner in a radially inward direction, or at least is pressed against the surface of the cable core (2.1, 2.2). [2] Cable (1) according to claim 1, characterized by, that the longitudinal webs (7), viewed in cross-section of each first profile wire (6), are tapered towards their free end. [3] Cable (1) according to claim 2, characterized by , that the longitudinal webs (7) are trapezoidal, convexly rounded or tapered in cross-section, or that at least the free ends of the longitudinal webs (7) are trapezoidal, convexly rounded or tapered in cross-section. [4] Cable (1) according to any one of claims 1 to 3, characterized by , that the cable core (2.1, 2.2) has a solid cross-section or a tubular cross-section. [5] Cable (1) according to any one of claims 1 to 4, characterized by , that the cable core (2.1, 2.2) has at least one electrical conductor (10) and / or signal conductor. [6] Cable (1) according to claim 5, characterized by, that the cable core (2.1, 2.2) has at least one means (12, 18) for electromagnetic shielding of the at least one electrical conductor (10) and / or signal conductor. [7] Cable (1) according to claim 6, characterized by , that at least one means (12, 18) for electromagnetic shielding is formed by a ribbon or tubular metal mesh and / or by a ribbon or tubular metal foil. [8] Cable (1) according to any one of claims 1 to 7, characterized by , that the cable core (2.1, 2.2) is additionally axially firmly connected to the armor (3) by material bonding. [9] Cable (1) according to claim 8, characterized by , that the material bond is effected by means of an adhesive (21). [10] Cable (1) according to any one of claims 1 to 9, characterized by , that at least one elevation (22.1, 22.2) extends along the profile wire (6, 8) or transversely to the longitudinal extent of the profile wire (6, 8). [11] Cable (1) according to any one of claims 1 to 10, characterized by , that the profile wires (6, 8) are made of steel. [12] Cable (1) according to any one of claims 1 to 11, characterized by , that the profile wires (6, 8) are stranded without twisting and undergo pre-shaping, and are laid in the stranding structure without tension. [13] Use of a cable (1) according to any one of claims 1 to 12 for geophysical measurement and exploration purposes or as a submarine cable (1) or other cable (1).

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