Cables of high stiffness, their use, and methods for their manufacture

Abstract

Cable (1) of high stiffness, comprising a cable core (2) which has one or more electrical conductors (4) and / or signal conductors, which are covered by a sheath (5) made of an insulating material or are integrally formed with said sheath (5), and an armor (3.1, 3.2) enclosing the cable core (2), wherein the armor (3.1, 3.2) is composed of at least one stranding layer of two groups of stranding wires of different cross-section arranged alternately around the circumference of the cable (1) with mutually complementary contact surfaces (8, 9; 16, 19), characterized in that at least one means (6) for electromagnetic shielding of the electrical conductors (4) and / or signal conductors is arranged on the outer sheath surface (7) of the sheath (5) made of insulating material or is integrated into the sheath (5), wherein the cable core (2) is enclosed with the armor (3.1, 3.2).2) is axially firmly connected by material, form and / or force connection and the form and / or force connection is effected by means of at least one protrusion (13.1, 13.2) which protrusion (13.1, 13.2) is formed on the contact surface (14) of at least one profile wire (11; 15, 18) facing towards the cable core (2) and penetrates the surface of the cable core (2) in a form-fitting manner in a radial inwards direction, or at least is pressed against the surface of the cable core (2).

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. According to claim 12 of the invention, it further relates to a method for manufacturing such a cable.

[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 performed both in open boreholes and after lowering a production pipe under production conditions, or in closed boreholes. The measuring heads or probes are either lowered along the measuring cable or positioned at a distal end of the cable before it is inserted into the borehole. This requires, however, that the measuring and exploration cables and associated measuring technology are designed to withstand the pressures, temperatures, and humidity inherent in the depths. Furthermore, to ensure cable insertion, particularly in horizontally drilled boreholes, axial force is required to overcome the frictional and braking resistance caused by contact with the borehole wall. This can only be achieved with a cable capable of withstanding sufficient thrust forces.

[0004] Prior art has identified measuring and exploration cables whose core is enclosed by an armor consisting of two layers of high-strength steel wires, particularly 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 ensure a uniform fit and alignment around the circumference of the cable.

[0005] Furthermore, cables of this type cannot effectively prevent the ingress of potentially aggressive media, such as fluids or solids. 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, due to insufficient axial stiffness and their non-media-tight armor, are unsuitable for greater depths and for surveying long horizontal boreholes with a shallow inclination.

[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 generic cable for geophysical measurement and exploration purposes, comprising a cable core with one or more conductor bundles and a stranded sheath forming an armor. The armor 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 basic 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] 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.Wrapped around the second dielectric layer are a coaxial shielding conductor, a second protective tape layer with a surrounding waterproof material, and an unspecified outer, load-bearing armor layer, which serves to provide external protection to the cable.

[0013] From 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.

[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, allows for interference-free transmission of electrical current and / or signals, and ensures a secure connection between the cable core and its supporting armor. According to a second aspect of the invention, the cable should reliably prevent the passage of fluids, in particular, through its outer sheath in deep boreholes, especially in offshore environments. According to a third aspect of the invention, the cable should allow the exploration and measurement of long boreholes, particularly horizontal ones or boreholes with a slight inclination, and consequently be able to withstand high compressive and tensile forces as well as differential internal pressures without any deformation.The object of the invention is also to provide a simple and cost-effective method for manufacturing such a cable.

[0016] Starting from a cable of high stiffness, in particular high axial stiffness, with a cable core comprising one or more electrical conductors and / or signal conductors, which are covered by a sheath made of an insulating material or are integrally formed with said sheath, and an armor covering the same, wherein the armor is composed 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 mutually complementary contact surfaces, the stated problem is solved by arranging or integrating at least one means for electromagnetic shielding of the electrical conductors and / or signal conductors on the outer sheath surface of the insulating material sheath, wherein the cable core is connected to the armor by fabric,The positive and / or force-fit connection is axially fixed and the positive and / or force-fit connection is effected by means of at least one protrusion, which protrusion is formed on the contact surface of at least one profile wire facing the cable core and penetrates the surface of the cable core in a radially inward direction, or at least is pressed against the surface of the cable core.

[0017] A cable of the type described is created which, with high fluid tightness, allows for the interference-free transmission of electrical current and / or signals. The aforementioned material, form, and / or force-fit between the armor and the cable core advantageously prevents axial relative movement between the cable armor and the cable core, thus enabling tensile and compressive forces to be absorbed and transmitted without interference during the intended use of the cable. Particularly in cables used for geophysical measurement and exploration purposes, the deep boreholes result in different elongations of the armor and cable core materials, which can conventionally lead to the aforementioned axial relative movement. Such relative movement can damage the cable's bond and consequently lead to its breakage or the distortion of measurement results.

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

[0019] The aforementioned sheath is preferably formed from a synthetic polymer that is easy and inexpensive to process. The synthetic polymer 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 is advantageously lightweight and particularly suitable for use as an electrical insulator. As further provided by the invention, the at least one means for electromagnetic shielding is preferably formed by an easily processed, ribbon-shaped or tubular metal mesh and / or by a ribbon-shaped or tubular metal foil. The metal mesh or metal strip consists, for example, of copper or a copper alloy.

[0020] According to a first advantageous embodiment of the invention, one group of stranding wires of the reinforcement is formed by round wires, whereas the other group of stranding wires is formed by profile wires. These profile wires have an arc-shaped cross-section, which is based on the basic geometry of a sector profile of a circular ring, and wherein the contact surfaces of the profile wires are concave and form-complementary to the contact surfaces of the adjacent round wires. Such a cable can transmit high compressive and tensile forces and exhibits high lateral stability and strength in the radial direction, thereby ensuring the integrity of the cable assembly even at great depths and under high pressures.In order to ensure particularly high lateral stability or strength in the radial direction, a second advantageous embodiment of the invention provides that the stranding wires of both groups each have an arc-shaped profile cross-section, which is based on the basic geometry of a sector profile of a circular ring, wherein one 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 have longitudinal grooves in the area of ​​their contact surfaces that correspond to said longitudinal webs of the immediately adjacent first profile wires and each of which receives a longitudinal web in a form-fitting manner.This measure results in a particularly effective positive connection between the profile wires of the reinforcement. As further provided by the invention, the round wires and profile wires of the at least one stranding layer are each made of steel, wherein the round wires are advantageously stranded with reverse twisting and the profile wires without reverse twisting, and the profile wires are also pre-formed by means of known pre-forming devices and placed into the stranding without tension. This measure ensures a high-quality layer structure of the stranding forming the reinforcement, in particular a tight bond between the stranding wires in the stranding layer.

[0021] As explained above, to 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 axially bonded to the armor by material, form, and / or force-fit. The 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 laid 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.

[0022] The at least one projection described above 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, for example, 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 form-fitting manner, or at least are pressed against the surface, thus preventing, or at least effectively hindering, the aforementioned axial relative movement.As mentioned above, the profile wires are made of a steel 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, at least one raised section is preferably formed during the production of the at least one profile wire using a rolling process.

[0023] 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.

[0024] A method for manufacturing the cable described above is characterized by the following steps: a) Provision of at least one elongated electrical conductor and / or signal conductor, b) Covering the at least one electrical conductor and / or signal conductor with a sheath made of an extrudable insulating material by means of at least one extruder, wherein the insulating material consists of a synthetic polymer, c) Application of at least one electrical shielding means to the outer surface of the jacket, wherein the at least one electromagnetic shielding means is formed by a ribbon or tubular metal mesh and / or by a ribbon or tubular metal foil, d) Transfer of the formed cable core to a stranding point of a stranding machine, and e) at the said stranding point, applying an armor consisting of at least one stranding layer of two groups of stranding wires of different cross-section arranged alternately around the circumference of the cable to the cable core, wherein the cable core is axially firmly connected to the armor by material, form and / or force connection, and the form and / or force connection is effected by means of at least one protrusion, which protrusion is formed on the contact surface of at least one profile wire facing the cable core and penetrates the surface of the cable core in a form-fitting manner in a radial inward direction, or at least is pressed against the surface of the cable core.

[0025] With regard to material protection, a step da) is provided between step d) and step e), which is characterized by the fact that, before the reinforcement is applied to the cable core at the aforementioned stranding point, the surface of the cable core is coated with an adhesive in such a way that, after the reinforcement has been applied according to step e), any voids that may be present, both between the stranding wires forming the reinforcement and between said reinforcement and the cable core, are filled by the adhesive. These measures, considered both individually and in combination, effectively prevent axial relative movement between the cable core and the reinforcement during the intended use of the cable, particularly as a geophysical measurement and exploration cable in long boreholes.

[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 perspective view of a cable designed according to the invention in a first embodiment variant, Fig. 2 the cable to Fig. 1 seen in cross-section, Fig. 3 a perspective view of a cable designed according to the invention in a second embodiment variant, Fig. 4 the cable to Fig. 3 seen in cross-section, Fig. 5a - 5d the details “Z1” to “Z4” after Fig. 4, with a detailed illustration of the cable's profile wires in four different embodiments thereof, Fig. 6a, Fig. 6b, based on the second embodiment, a cable designed according to the invention seen in cross-section according to a third embodiment, with two further advantageous embodiments of the profile wires, and Fig. 7 extremely schematically a representation of a suitable method for manufacturing a cable according to the invention. Option 1:

[0027] The Fig. 1 and Fig. Figure 2 shows a first embodiment of a cable 1 designed according to the invention, comprising a cable core 2 which itself has a solid cross-section and is sheathed by a stranded structure forming an armor 3.1. In particular, the armor 3.1 provides the axial and radial stability and stiffness of the cable 1, respectively.

[0028] The cable core 2 exhibits, according to the Fig. 1 and Fig. Figure 2 of the embodiment of the invention shows, by way of example only, a single electrical conductor 4, in particular a copper conductor. The electrical conductor 4 is covered by a sheath 5 made of a synthetic polymer, so to speak, embedded in the sheath 5. The sheath 5 is preferably applied to the electrical conductor 4 by an extrusion process known per se. The synthetic polymer for forming the sheath 5 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. In addition, ETFE advantageously has a low weight and is particularly advantageous for use as an electrical insulator.

[0029] Instead of the single electrical conductor 4 mentioned above, a signal conductor (not shown in the drawing), for example in the form of an optical fiber made of preferably high-temperature-resistant fiberglass, can also be provided. Advantageously, the cable core 2 can also have one or more conductor bundles, which are formed, for example, by electrical conductors 4 and / or signal conductors, such as optical fibers (not shown in the drawing). Advantageously, the electrical conductors 4 or signal conductors or conductor bundles themselves can be enclosed in a media-tight sheath and then additionally covered by the aforementioned sheath 5 (not shown in the drawing).

[0030] The cable core 2 has a means 6 for electromagnetic shielding of the single electrical conductor 4, which is shown by way of example. The means 6 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 6 for electromagnetic shielding, or the metal mesh or metal foil, is applied to the outer sheath surface 7 of the sheath 5, for example, wound or braided onto the sheath 5 as a strip or pulled onto the sheath 5 as a tube.

[0031] In contrast, the electromagnetic shielding agent 6, i.e., the metal mesh or metal foil, can be embedded in or integrally formed with the sheath 5. In this case, the electromagnetic shielding agent 6, i.e., the metal mesh or metal foil, functions as an insert, so to speak, by being continuously embedded in the extrusion mass of the sheath 5 during its production using the aforementioned extrusion process (not shown in the drawing here, but see [reference]). Fig. 6a, Fig. 6b and its explanations). The aforementioned insert advantageously results in a reinforcement of the sheath 5.

[0032] According to the Fig. 1 and Fig. 2 The armoring 3.1 is constructed from a stranding layer of two groups of stranding wires of different cross-sections arranged alternately around the circumference of the cable 1, with contact surfaces 8, 9 that are complementary to each other. One group of stranding wires is formed by round wires 10, whereas the other group of stranding wires is formed by profile wires 11. The profile wires 11 have an arc-shaped profile cross-section, which is based on the basic geometry of a sector profile of a circular ring, so that the contact surfaces 9 of the profile wires 11 are concave and complementary to the contact surfaces 8 of the adjacent round wires 10.

[0033] The round and profile wires 10, 11 preferably consist of a steel that is itself suitable for withstanding high and extremely high forces acting on the cable 1, for example, when the same is used for geophysical measurement and exploration purposes, particularly in the oil and gas production industry. To achieve a high-quality layer structure of the stranded assembly forming the reinforcement 3.1, the round wires 10 are stranded with reverse twisting and the profile wires 11 are stranded without reverse twisting and placed in the stranded assembly without tension, the profile wires 11 undergoing a corresponding pre-forming beforehand by means of pre-forming devices known per se.

[0034] In order to effectively prevent axial relative movement between the cable core 2 and the armor 3.1 during the intended use of the cable 1, in particular as a geophysical measuring and exploration cable in long boreholes, the cable core 2 is axially firmly connected to the armor 3.1 by material, form and / or force connection.

[0035] According to the Fig. 1 and Fig. 2. The aforementioned material bond is preferably achieved by means of an adhesive 12, which is applied to the cable core 2 and cures after the cable core 2 is sheathed with the armor 3.1 or after the stranding wires or the round and profile wires 10, 11 are wound onto the cable core 2. The adhesive 12 advantageously also acts as a sealant by filling any remaining voids between the round and profile wires 10, 11 of the armor 3.1 of the cable 1 and between the round and profile wires 10, 11 and the cable core 2, thereby ensuring a particularly high fluid tightness of the cable 1. The adhesive 12 preferably consists of a suitable synthetic polymer.

[0036] Regarding the aforementioned positive and / or force-fit connection between the armor 3.1 of the cable 1 and the cable core 2, this is effected by means of at least one projection 13.1, 13.2 on a contact surface 14 of at least one profile wire 11 facing the cable core 2. The at least one projection 13.1, 13.2 extends radially inwards from said contact surface 14, causing it to engage positively with the surface of the cable core 2 during the stranding process, or at least be pressed against the surface of the cable core 2, thus preventing, or at least effectively hindering, axial relative movement between the armor 3.1 and the cable core 2.

[0037] Fig. Figure 2 shows, for the sake of simplicity, two embodiments of a positive-locking joint in addition to the material-bonded joint. These embodiments are represented by projections 13.1 and 13.2, which can be used alternatively or in combination (each shown as a dashed line). The projection 13.1 extends along the profile wire 11. Due to the stranding, the projection 13.1 coils helically around the cable core 2 and thereby engages its surface in a positive-locking manner. This prevents, or at least effectively hinders, axial relative movement between the profile wire 11 and the cable core 2. Preferably, however, a plurality of the profile wires 11, and more preferably all of them, are equipped with at least one such projection 13.1 (not shown in the drawing).

[0038] In contrast, the projection 13.2 extends transversely to the longitudinal extent of the profile wire 11. If several such projections 13.2 are provided for each profile wire 11, a contact surface 14 is formed with the cable core 2, which, like a rack, has alternating projections 13.1, so to speak, teeth, and tooth gaps, at least in sections. The teeth engage positively with the surface of the cable core 2, thereby preventing, or at least effectively hindering, axial relative movement between the profile wire 11 and the cable core 2. Preferably, a plurality of the profile wires 11, and more preferably all profile wires 11, are equipped with at least one such projection 13.2 (not shown in the drawing).

[0039] As already explained above, the profile wires 11 preferably consist of a steel that is suitable for withstanding high and extremely high forces acting on the cable 1, for example, when the same 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 13.1, 13.2 is preferably formed on the profile wire 11 during its manufacture by a rolling process. Option 2:

[0040] The Fig. Figures 3 to 5d show a second embodiment of the cable 1 according to the invention, wherein functionally identical parts are designated with the same reference numerals as in the previous drawing figures, so that for their explanation reference is made to the preceding description of embodiment 1.

[0041] This second embodiment of the cable 1 differs from the first embodiment described above essentially in that an armoring 3.2 is provided in which one of the two groups of stranding wires is formed by first profile wires 15, which first profile wires 15 have at least one longitudinal web 17 extending along the profile wire 15 on both sides of the sector profile in the area of ​​their contact surfaces 16. However, the invention is not limited to one longitudinal web 17 per contact surface 16, but also encompasses two or more longitudinal webs 17 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 16 (not shown in the drawing).The other group of stranding wires is formed by second profile wires 18, which, in the area of ​​their contact surfaces 19, each have longitudinal grooves 20 corresponding to the aforementioned longitudinal webs 17 of the immediately adjacent first profile wires 15 and each receiving one longitudinal web 17 in a form-fitting manner. This measure results in a particularly effective form-fitting connection between the first and second profile wires 15, 18 of the reinforcement 3.2.

[0042] According to the Fig. 3, Fig. 4 and Fig. 5a The longitudinal webs 17 and the longitudinal grooves 20, 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 17 extend on a normal to the radius of the cable 1. This results in a high resistance of the profile wires 15, 18 to radial disintegration of the reinforcement 3.2.

[0043] To facilitate the production of the reinforcement 3.2, in particular the stranding of the first and second profile wires 15, 18 with positive locking to one another, it is provided that the longitudinal webs 17 of the first profile wires 15, viewed in cross-section of each first profile wire 15, are designed to taper towards their free end. This measure allows the longitudinal webs 17 to be easily inserted into the respective, form-complementary longitudinal groove 20 during the production of the reinforcement 3.2. The longitudinal webs 17 are preferably trapezoidal in cross-section ( Fig. 5b) or convexly rounded ( Fig. 5c). It is also conceivable, and accordingly covered by the invention, to provide a tapered cross-section for the longitudinal webs 17 (not shown in the drawing).

[0044] An equivalent, or at least a similar, effect can be achieved if at least the free ends of the longitudinal webs 17 are trapezoidal in cross-section (cf. Fig. 5d) or convexly rounded or tapered (not shown in the drawing). This measure has the advantage that, while ensuring high resistance of the profile wires 15, 18 to radial disintegration of the reinforcement 3.2, the joining of the profile wires 15, 18 to one another is also simplified. Each longitudinal web 17 has a first, profile-side section 17a with radially inward and radially outward facing surfaces that lie on a normal to the radius of the cable 1, wherein at least one of the aforementioned first sections 17a then transitions into a second, free end section 17b, which is inclined such that the cross-section of the longitudinal web 17 tapers in this end section 17b.

[0045] In a further development of the invention, an interference fit (press fit) can be achieved by a specific design of the longitudinal webs 17 in relation to the longitudinal grooves 20 that receive them in a form-fitting manner, thereby advantageously combining the form-fitting with a frictional fit (not shown in the drawing). This further increases the strength of the composite of the reinforcement 3.2 as well as the fluid tightness of the cable 1.

[0046] With regard to the material, form, and / or force-fit connection between the cable core 2 and the armoring 3.1, which is described in detail in the first embodiment of the invention, such a material, form, and / or force-fit connection can, of course, also be provided between the cable core 2 and the armoring 3.2 and is accordingly covered by the invention. Fig. 3, Fig. 4 to Fig. Figure 5 shows a material bond using the adhesive 12 mentioned above. For the sake of clarity, a representation of the form-fit and / or force-fit connection as described above has been omitted in this embodiment. Option 3:

[0047] The Fig. 6a and Fig. Figure 6b shows, in accordance with embodiment 2, a third embodiment of the cable 1 according to the invention, wherein functionally identical parts are designated with the same reference numerals as in the previous drawing figures, so that for their explanation reference is also made to the preceding descriptions of embodiments 1 and 2.

[0048] According to this embodiment, the material bond is combined with a form-fit and / or force-fit between the cable core 2 and the armor 3.2, wherein here too the material bond is achieved by means of an adhesive 12 and the form-fit and / or force-fit by means of the raised sections 13.1 described for embodiment variants 1 and 2 ( Fig. 2, Fig. 6a) and / or 13.2 ( Fig. 2, Fig. 6b) is effected. Moreover, a cable core 2 with a sheath 5 is shown here, in which the electromagnetic shielding means 6 is embedded. That is, synthetic polymer, ETFE according to this embodiment, is also applied radially to the outside of the electromagnetic shielding means 6, which, when the electromagnetic shielding means 6 is formed as a metal mesh, penetrates or fills its openings and cavities.

[0049] The preceding embodiments refer to a cable 1 with a cable core 2 and an armor 3.1 or 3.2 sheathing the cable core 2, which armor 3.1 or 3.2 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 3.1 or 3.2 formed by a plurality of layers of the described type (not shown in the drawings). The stranding layers described above can be combined in any way desired.

[0050] The invention will now be further described using a Fig. Figure 7 describes a preferred manufacturing plant for producing a cable 1 of the type according to the invention. The manufacturing process is continuous in this case. A discontinuous process is certainly also conceivable and is accordingly covered by the invention. The plant for producing the cable 1 essentially comprises the following individual devices: - A winding 21 comprising a provided winding coil 22. The winding coil 22 is pre-wound with at least one elongated electrical conductor 4, a signal conductor, for example in the form of an optical waveguide made of a preferably temperature-resistant fiberglass, or a conductor bundle formed, for example, by electrical conductors 4 and / or signal conductors, such as optical waveguides; - At least one first extruder 23, by means of which the sheath 5 described above, made of an extrudable insulating material, in particular a synthetic polymer, preferably ETFE (ETFE = ethylene tetrafluoroethylene), is applied to the at least one elongated electrical conductor 4, the signal conductor or the conductor bundle; - A cooling section 24, by means of which the jacket 5 made of extrudable insulating material is subjected to cooling and thus hardening; - A braiding machine 25, by means of which an electromagnetic shielding means 6 in the form of a band-shaped metal mesh or a band-shaped metal foil is braided onto the said sheath 5. The metal mesh or the metal foil preferably consists of copper or a copper alloy; - A stranding machine 26, in particular a basket stranding machine 26 with at least one stranding basket which carries several unwinding spools (not shown in the drawing) for the stranding wires. By means of the stranding machine 26, an armoring 3.1 or 3.2 consisting of at least one layer of stranding wires is applied to the formed cable core 2 at a stranding point 27; - A pulley 28, in this case a disc pulley, which continuously pulls the components of the cable 1 and ultimately the finished cable 1 through the production plant; and - a winder 29 with a winding spool 30 for the finished cable 1.

[0051] To effectively prevent axial relative movement between the cable core 2 and the reinforcement 3.1 during the intended use of the cable 1, particularly as a geophysical measurement and exploration cable in long boreholes, a device for applying an adhesive 12 to the cable core 2 is arranged in the area of ​​the stranding point 27. A second extruder 31 is used for this purpose. Essentially, the stranding wires, namely round wires 10 and profile wires 11 or first and second profile wires 15, 18, are fed into a die of the second extruder 31 filled with adhesive 12 and applied to the cable core 2 within the second extruder 31 to form the reinforcement 3.1 or 3.2. The stranding point 27 is thus located within the die of the second extruder 31.

[0052] In contrast, or in combination with the above measure, a form-fit and / or force-fit can be effected between the reinforcement 3.1, 3.2, in particular its profile wires 11; 15, 18, and the cable core 2 by forming at least one radially inwardly directed projection 13.1, 13.2 on a contact surface 14 of said profile wires 11; 15, 18 facing the cable core 2, which projection 13.1, 13.2 penetrates the surface of the cable core 2 in a form-fit manner during the stranding process at the stranding point 27, or at least is pressed against the surface of the cable core 2 (see in particular...). Fig. 2, Fig. 6a, Fig. 6b). Reference symbol list 1 cable 2 cable cores 3.1 Reinforcement 3.2 Reinforcement 4 electrical conductors 5 coat 6 means of electromagnetic shielding 7 Outer surface area (shell 5) 8 contact surfaces (round wire 10) 9 contact surfaces (profile wire 11) 10 round wire 11 Profile wire 12 Adhesive 13.1 Survey 13.2 Survey 14 Contact area 15 first profile wires 16 contact surfaces (first profile wires 15) 17 Longitudinal web 17a first section 17b second section 18 second profile wires 19 contact surfaces (second profile wires 18) 20 longitudinal grooves 21 Procedure 22 Unwinding coil 23 first extruder 24 Cooling section 25 braiding machine 26 Stranding machine 27 Stranding point 28 deduction 29 winders 30 winding spool 31 second extruder

Claims

[1] Cable (1) of high stiffness, comprising a cable core (2) comprising one or more electrical conductors (4) and / or signal conductors, which is / are covered by a sheath (5) made of an insulating material or is / are integrally formed with said sheath (5), and an armor (3.1, 3.2) enclosing the cable core (2), wherein the armor (3.1, 3.2) is composed of at least one stranding layer of two groups of stranding wires of different cross-section arranged alternately around the circumference of the cable (1) with contact surfaces (8, 9; 16, 19) that are complementary in shape to each other, characterized by, that on the outer sheath surface (7) of the sheath (5) made of insulating material at least one means (6) for electromagnetic shielding of the electrical conductors (4) and / or signal conductors is arranged or integrated into the sheath (5), wherein the cable core (2) is axially fixedly connected to the armor (3.1, 3.2) by material, form and / or force connection and the form and / or force connection is effected by means of at least one projection (13.1, 13.2) which projection (13.1, 13.2) is formed on the contact surface (14) of at least one profile wire (11; 15, 18) facing the cable core (2) and penetrates the surface of the cable core (2) in a form-fitting manner in a radially inward direction, or at least is pressed against the surface of the cable core (2). [2] Cable (1) according to claim 1, characterized by , that the said sheath (5) is formed from an insulating material by a synthetic polymer. [3] Cable (1) according to claim 1 or 2, characterized by, that at least one means (6) for electromagnetic shielding is formed by a ribbon or tubular metal mesh and / or by a ribbon or tubular metal foil. [4] Cable (1) according to any one of claims 1 to 3, characterized by , that one group of stranding wires is formed by round wires (10), whereas the other group of stranding wires is formed by profile wires (11), which profile wires (11) have an arc-shaped profile cross-section which is based on the basic geometry of a sector profile of a circular ring, and wherein the contact surfaces (9) of the profile wires (11) are concave in form complementary to the contact surfaces (8) of the adjacent round wires (10). [5] Cable (1) according to any one of claims 1 to 3, characterized by, that the stranding wires of both groups each have an arc-shaped profile cross-section which is based on the basic geometry of a sector profile of a circular ring, wherein one group of stranding wires is formed by first profile wires (15) which first profile wires (15) have at least one longitudinal web (17) extending along the profile wire (15) on both sides of the sector profile in the area of ​​their contact surfaces (16), whereas the other group of stranding wires is formed by second profile wires (18) which second profile wires (18) have longitudinal grooves (20) corresponding to said longitudinal webs (17) of the immediately adjacent first profile wires (15) in the area of ​​their contact surfaces (19) and each receiving a longitudinal web (17) in a form-fitting manner. [6] Cable (1) according to claim 4 or 5, characterized by , that the round wires (10) and profile wires (11; 15, 18) of at least one stranding layer each consist of a steel. [7] Cable (1) according to any one of claims 4 to 6, characterized by , that the round wires (10) are stranded with reverse twisting and the profile wires (11; 15, 18) are stranded without reverse twisting. [8] Cable (1) according to any one of claims 4 to 7, characterized by , that the profile wires (11; 15, 18) undergo pre-shaping and are laid in the stranded bond without tension. [9] Cable (1) according to any one of the preceding claims, characterized by that the bond between the materials is achieved by means of an adhesive. [10] Cable (1) according to any one of the preceding claims, characterized by , that at least one elevation (13.1, 13.2) extends along the profile wire (11; 15, 18) or transversely to the longitudinal extent of the profile wire (11; 15, 18). [11] Use of a cable (1) according to any one of claims 1 to 10 for geophysical measurement and exploration purposes or as a submarine cable (1) or other cable (1). [12] Method for manufacturing a cable (1) according to any one of claims 1 to 10, characterized by the following steps: a) Provision of at least one elongated electrical conductor (4) and / or signal conductor, b) Covering the at least one electrical conductor (4) and / or signal conductor with a sheath (5) made of an extrudable insulating material by means of at least one extruder (23), wherein the insulating material consists of a synthetic polymer, c) Applying at least one electrical shielding means (6) to the outer surface (7) of the sheath (5), wherein the at least one electromagnetic shielding means (6) is formed by a ribbon or tubular metal mesh and / or by a ribbon or tubular metal foil, d) Transfer of the formed cable core (2) into a stranding point (27) of a stranding machine (26), and e) at said stranding point (27) application of an armor (3.1, 3.2) consisting of at least one stranding layer of two groups of stranding wires of different cross-section arranged alternately around the circumference of the cable (1) onto the cable core (2), wherein the cable core (2) is axially fixedly connected to the armor (3.1, 3.2) by material, form and / or force connection and the form and / or force connection is effected by means of at least one protrusion (13.1, 13.2) which protrusion (13.1, 13.2) is formed on the contact surface (14) of at least one profile wire (11; 15, 18) facing the cable core (2) and penetrates the surface of the cable core (2) in a form-fitting manner in a radially inward direction, or at least is pressed against the surface of the cable core (2). [13] Method according to claim 12, characterized by, that with regard to the material bond between step d) and step e), a step da) is carried out, which is characterized in that, prior to the application of the armor (3.1, 3.2) at the said stranding point (27) to the cable core (2), the surface of the cable core (2) is wetted with an adhesive (12) in such a way that, after the application of the armor (3.1, 3.2) according to step e), any voids to be observed both between the stranding wires forming the armor (3.1, 3.2) and between said armor (3.1, 3.2) and the cable core (2) are filled by the adhesive (12).

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