Rotation-resistant wire rope, method for producing same, and hoisting apparatus comprising a drum drive

Abstract

The invention relates to a non-rotating wire rope (1; D1', D2'), in particular a non-rotating round wire rope, which has a core cable (2) and outer wires (4) which surround the core cable, said outer wires forming a single outer wire layer (3). Advantageously, the core cable (2) comprises multiple core cable inner wires (5, 6) which are introduced into a plastic matrix (9) and which are surrounded by core cable outer wires (8) that form a core cable outer layer (7). Advantageously, a relative movement of the core cable wires can be carried out in the longitudinal direction as well as in the circumferential direction. The invention additionally relates to a method for producing a non-rotating wire rope and to a lifting device comprising a drum drive which has a non-rotating wire rope according to the invention, said wire rope being designed as a running cable.

Description

[0001] The invention relates to a non-rotating wire rope, in particular a non-rotating round stranded rope, which has a core rope and outer strands surrounding the core rope, forming a single outer strand layer.

[0002] Furthermore, the invention relates to a method for manufacturing a rotation-free wire rope and a lifting device with a drum drive, which has a rotation-free wire rope according to the invention, wherein this rope is designed as a running rope.

[0003] A hammered, non-rotation-resistant wire rope is known from DE 20 2013 102 594 U1. Rotation-resistant wire ropes are known from DE 39 37 588 A1, CH 545881 A, DE 29 49 754 C2 and "Special Wire Ropes / / Spezialdrahtseile / The Premium Line" (available on September 25, 2024 at https: / / www.casar.de / Portals / 0 / Documents / Product-Specs / powerplast.pdf). Each of these known wire ropes has a core rope that is completely embedded in a plastic matrix, meaning its core strands are completely surrounded by the plastic of the matrix.

[0004] To create the plastic matrix, it is also known from the prior art, in particular from DE 39 37 588 A1, that incomplete strands form a core rope. Incomplete means that individual strand wires were omitted during the production of the strands, thereby forming a channel through which a plastic matrix-forming polymer can flow into the core rope during core rope production and completely surround the core rope strands.

[0005] Whether a wire rope is rotation-free can be determined by a standardized test described in ISO 21669 ("Wire ropes made of steel wire - Determination of rotational properties"; version: 02 / 2005): A wire rope with a length of 1000 xd (d = nominal diameter of the wire rope) is subjected to a tensile load F, where the force F corresponds to 20% of the minimum breaking strength (= F min ) of the wire rope. The angle of rotation φ of the wire rope is determined, the angle by which the wire rope rotates about its longitudinal axis under the specified load. For a rotation-free wire rope, the following applies: - 360° < φ < 360°.

[0006] The invention is based on the objective of creating a particularly stable, rotation-free wire rope of the type mentioned above with a long service life.

[0007] Furthermore, the invention is based on the objective of creating a device with a drum drive that requires particularly little maintenance.

[0008] According to the invention, the problem is solved by the core rope comprising several core rope inner strands which are embedded in a plastic matrix and which are surrounded by core rope outer strands which form a core rope outer strand layer.

[0009] Because only the core rope inner strands are fully embedded in the plastic matrix in one circumferential direction, they do not lie directly against each other and are therefore movable relative to each other when a rotation-free wire rope according to the invention is under load, for example when used as a running wire rope in a device with a drum drive such as a crane. Advantageously, relative movement of adjacent core rope inner strands can occur under load in both a longitudinal and a circumferential direction.

[0010] The inventor has determined that by using a core rope of the aforementioned design, a twist-free wire rope with a particularly high actual breaking strength Fm is created despite a relatively low core rope fill factor. According to the prior art, a wire rope is more break-resistant the larger its fill factor. The fill factor is the ratio of the cross-sectional area of ​​all wires forming the wire rope to the total cross-sectional area of ​​the wire rope.

[0011] A fill factor of 0.70, for example, means that 70% of the wire rope cross-section consists of the wires forming the wire rope.

[0012] In particular, the inventor has surprisingly found that a wire rope according to the invention with a core rope of the type mentioned has a higher actual breaking strength F m than a wire rope of the same design with a higher core rope filling factor, despite a lower core rope filling factor.

[0013] Overall, the inventor has overcome the technical prejudice that a high fill factor is required for high tensile strength, which is expressed by the actual breaking force F m.

[0014] The actual breaking force F m is a general term known to those skilled in the art for a wire rope property and can be determined according to DIN EN 12385-3 (version: 01 / 2009), section 6.4).

[0015] Wire ropes are classified into so-called rope strength classes, with each rope strength class representing a rope with a specific actual breaking strength Fm. To achieve a high actual breaking strength Fm, the wires forming the wire rope must reach certain tensile strengths known from standards. Since wires with high tensile strength are brittle, wire ropes with a high actual breaking strength Fm are typically not very resistant to bending fatigue. Because a rotation-free wire rope according to the invention, with a core rope of the type mentioned, has a higher actual breaking strength Fm than a comparable rotation-free wire rope with a core rope known from the prior art, the wire rope according to the invention can be manufactured using wires with lower tensile strength, while still achieving the required higher rope strength class.Such wires with lower tensile strength are less brittle, so that a rotation-free wire rope according to the invention is created with particularly good flexural fatigue strength and simultaneously high actual breaking force F m.

[0016] Elastomers or thermoplastics are particularly suitable as plastics for forming the plastic matrix, especially polyethylene (PE) or polypropylene (PP).

[0017] According to the invention, only the multiple inner strands of the core rope are completely embedded in the plastic matrix.

[0018] The inventor realized that to produce a particularly durable wire rope, it is not necessary to encase the entire core rope in a plastic matrix, but surprisingly, it is sufficient if the inner strands of the core rope are completely surrounded by plastic and embedded in the plastic matrix.

[0019] Advantageously, a simple, durable wire rope is created, which is particularly suitable for use as a running wire rope in a device with a drum drive.

[0020] In one embodiment of the invention, the core rope outer strands, which are only partially embedded in the plastic matrix, lie directly against the outer strands with the core rope outer strand areas facing away from the core rope inner strands.

[0021] The inventor has discovered that core rope inner strands fully embedded in the polymer matrix and core rope outer strands partially embedded in the polymer matrix already result in an increase in mechanical properties. This is surprising, since it is known from the prior art that a core rope must be fully embedded in a polymer matrix in order to achieve high fatigue strengths when the wire rope is used as a running wire rope.

[0022] Because the outer core strand areas facing the inner core strands are surrounded by plastic, they are movable in a longitudinal direction relative to the inner core strands and do not lie directly against each other.

[0023] The inventor surprisingly discovered that high fatigue strength, manifested, for example, in a high number of bending cycles before reaching the end of its service life, is possible even though the outer strands of a rotation-free wire rope according to the invention are in direct contact with the outer strands of the core rope. This is surprising because the prior art shows that a plastic interlayer is required between the core rope and the outer strands to prevent direct contact between adjacent wires, thereby reducing wear and extending the service life of the wire rope.

[0024] Advantageously, the outer strands of the core rope are only inserted into the plastic matrix with the areas of the outer strands facing the inner strands of the core rope, and the outer strands of the core rope facing away from the inner strands of the core rope are not inserted into the plastic matrix.

[0025] Partial embedding in the polymer matrix ensures that the core rope outer strands are movable relative to the core rope inner strands. At the same time, the outer strands lie directly against the core rope outer strands.

[0026] It has proven advantageous for high flexural fatigue strength if the core rope outer strands are embedded in the plastic matrix with at least half of their base area facing the core rope inner strands.

[0027] The inventor has surprisingly discovered that embedding all the core rope strands in a plastic matrix is ​​not necessary to achieve improved properties. Furthermore, this results in a twist-free rope that requires less plastic to manufacture.

[0028] In one embodiment of the invention, adjacent core rope outer strands are separated from each other by the plastic matrix, which extends from the core rope inner strands in the radial direction of the wire rope to the core rope outer strands, wherein the plastic matrix extends in the radial direction of the core rope only to the extent that core rope outer strand areas facing away from the core rope inner strands are not incorporated into the plastic matrix.

[0029] It has proven advantageous for high flexural fatigue strength if the core rope outer strands are embedded in the plastic matrix with at least half of their base area facing the core rope inner strands.

[0030] Advantageously, core rope strands adjacent to each other in the radial or circumferential direction are not in direct contact with one another. Particularly good relative mobility of the core rope strands to each other is ensured, even though the outer core rope strands are only partially embedded in the polymer matrix in their circumferential direction.

[0031] In one embodiment of the invention, the core rope is compacted.

[0032] Preferably, only the core rope is compacted, not the entire wire rope. A compacted core rope differs from a core rope made from compacted strands in that the compaction takes place after the core rope has been manufactured. Compaction occurs before an outer strand layer is applied to the core rope. Preferably, the core rope is hammered. Other compaction methods are conceivable. Compacting the core rope also creates a flat and smooth core rope surface. An outer strand layer, which is applied to the core rope to form the wire rope, can, for example, be applied directly to this flat and smooth surface. Damage caused by individual wires of the core rope outer strands touching the outer strands of the non-rotating wire rope can be advantageously prevented.

[0033] A further advantage is that the outer strands of the wire rope are movable relative to the core rope; that is, they can slide along the flat and smooth surface of the core rope when the wire rope is under load. This prevents stress conditions that could damage the wires.

[0034] It is understood that core rope strands, in particular inner and / or outer core rope strands, may already be compacted. Each of the strands forming the core rope can be compacted before being stranded together to form the core rope, and the core rope itself can be further compacted after its manufacture.

[0035] In a further embodiment of the invention, the outer strands are applied directly to the core rope.

[0036] A further increase in mechanical properties, in particular an increase in flexural fatigue strength, is possible when the core rope is additionally compacted.

[0037] This finding is surprising, since the prior art teaches that break-resistant and fatigue-resistant wire ropes for use as running wire ropes can only be created if friction between wires of adjacent strands is largely prevented. This can be achieved, for example, by a plastic layer between the core rope and the outer strand layer. However, according to the invention, this is not necessary; rather, the outer strand layer can be applied directly to the core rope in such a way that, in the radial direction, adjacent wires of core rope outer strands and outer wires of outer strands are in direct contact with each other.

[0038] The inventor recognized that by applying an outer strand layer directly onto the core rope, a rotation-free wire rope is created that is particularly break-resistant.

[0039] According to a variant not covered by the claims, the wire rope has a covering, preferably made of a plastic, between the core rope and the outer strand layer, which has no connection to the plastic matrix.

[0040] The sheath surrounds the core rope in the manner of a casing, which can be produced in particular by an additional process step, and into which the core rope is inserted.

[0041] No connection means that a clear separation is possible between the plastic surrounding the core rope's inner strands and the plastic sheath, which has no connection to the plastic matrix. This is made possible, in particular, by a separation plane formed between the plastic matrix and the plastic sheath. This separation plane creates a sliding plane that allows the outer strands to move relative to the core rope in a longitudinal direction.

[0042] The inventor has found that such a covering further improves the relative mobility of the core rope to the outer strand layer, making such a rotation-free wire rope according to the invention particularly durable, even under high loads, for example, winding and unwinding from a wire rope drum.

[0043] Although not strictly necessary, it is conceivable that the plastic matrix surrounding the inner strands of the core rope is made of a different plastic than the plastic sheathing of the core rope.

[0044] In a further embodiment, which is not covered by the claims, the outer strands of the core rope are embedded in the plastic matrix with the core rope outer strand areas facing the inner strands, and the outer strand areas facing away from the inner strands are inserted into a covering made of a plastic material, arranged between the core rope and the outer strand layer, wherein the covering has no connection to the plastic matrix and completely surrounds the core rope in a circumferential direction.

[0045] The sheath surrounding the core rope, which in particular has no connection to the plastic matrix, forms a separation plane, thereby creating a sliding plane that allows relative movement of the outer strands to the core rope in a longitudinal direction.

[0046] Advantageously, a particularly durable, especially bend-resistant, wire rope is created, which is especially suitable for use as a running wire rope. The core rope is expediently a parallel-laid rope.

[0047] In a parallel lay rope, all the wires from which the parallel lay rope is made are twisted together in a single process step to form parallel lay strands, which are then twisted together to form the parallel lay rope.

[0048] In a parallel lay rope, core outer strands of a core rope are arranged between circumferentially adjacent outer strands of a first outer strand layer due to the manufacturing process.

[0049] The inventor has determined that a core rope with a 1+8+8 construction results in a particularly break-resistant and flexurally resistant, rotation-free wire rope whose mechanical properties are between 30% and 60% better than those of known rotation-free wire ropes. A core rope with a 1+8+8 construction is a wire rope in which the core rope has eight inner core rope strands (first "+8") surrounding an innermost core rope strand ("1"), which are in turn surrounded by eight outer core rope strands (second "+8").

[0050] Surprisingly comparable strength properties were found for other core rope constructions, for example for a filler rope of the type 1 + n + n F + 2n, where n = 3, 4, 5 ... and nF is a number of so-called filler wires, or for a Warrington rope of the type 1 + n + (n + n), where n = 3, 4, 5 ..., or for a Seale rope of the type 1 + n + n, where n = 3, 4, 5, ..., or for a Warrington-Seale rope of the type 1 + n + (n + n) + 2n, where n = 3, 4, 5 ...

[0051] An overview of the aforementioned methods and details thereof are described in the VDI guideline 2358 (version: 12 / 2012) in chapter 6.2.1.2.

[0052] In a further embodiment of the invention, the rotation-free wire rope has an actual breaking force F m that is between 3% and 45% higher than the actual breaking force F m of a wire rope of the same type in which the core rope inner strands are not embedded in a plastic matrix.

[0053] A wire rope of the same construction means that the two ropes being compared have a core rope of the same construction and an outer layer of the same construction. It is understood that the rope diameter is also the same.

[0054] The actual breaking force F m of a wire rope increases or decreases linearly with its wire rope cross-sectional area, whereby this relationship applies in particular to a nominal wire rope diameter between 10 mm and 60 mm.

[0055] The inventor has surprisingly discovered that the actual breaking strength F m can be increased by the aforementioned values ​​compared to a comparable wire rope without core rope inner strands embedded in a plastic matrix, provided that only the core rope inner strands are completely embedded in the plastic matrix.

[0056] To determine the percentage increase, an actual breaking strength Fm1 is determined for a first wire rope D1 with a diameter d and no core strands embedded in a plastic matrix. This value represents 100% of the actual breaking strength Fm1 of the first wire rope D1 and serves as a reference value. Next, an actual breaking strength Fm2 is determined for a second wire rope D2 with a diameter d, and this wire rope D2 has core strands embedded in a plastic matrix. The actual breaking strength Fm2 of the second rope D2 is then compared to the actual breaking strength Fm1 of the first rope D1. This ratio is the relative actual breaking strength.

[0057] According to the invention, the ratio F m2 / F m1 is between 1.03 and 1.45.

[0058] In one embodiment of the invention, the wire rope, at a nominal tensile stress σz of 127 N / mm² < ± 10 N / mm² <, has a service life in bending cycles that is between 3% and 40% higher than that of a wire rope of the same design in which the core rope inner strands are not embedded in a plastic matrix.

[0059] The nominal tensile stress σZ, also known as rope tensile stress, is defined as a rope tensile force S divided by a metallic cross-section, i.e., the sum of the cross-sections of all wires forming the wire rope (Source: FEYRER: Drahtseile, K. Feyrer, K.-H. Wehking, 3rd edition, SpringerVieweg, 2018, ISBN: 978-3-642-54295-4, there p. 71).

[0060] Service life is defined as the number of bending cycles until a wire rope breaks.

[0061] The so-called 100% discard criterion is the number of bending cycles a wire rope can withstand before its safe continued use is no longer possible. Once the discard criterion is reached, the wire rope must be replaced.

[0062] The number of bending cycles after which a wire rope reaches 100% discard maturity is always less than its service life. The higher the service life and the higher the discard maturity, the more resistant a wire rope is to bending cycles.

[0063] To determine the service life, a test setup according to R. Verreet, J.-M. Teissier "A new and innovative wire rope bending fatigue machine" (2005, freely available at https: / / www.ropetechnology.com / downloads / brochures / bro_a-new-and-innovative-wire-rope-bending-fatigue-machine.pdf; last accessed on November 24, 2023) was used. In this setup, a wire rope is guided over a total of five pulleys under load with a selected nominal tensile stress until the wire rope breaks (see Figures 6 to 8 in the same publication).

[0064] An advantage of this test setup is that the broken wire rope has areas of less wear, allowing values ​​such as a specific degree of discard (20%, 40%, 60%, 80%, 100%) to be determined for the broken wire rope (see Fig. 9). The test thus determines the number of bending cycles for each section of the wire rope, enabling the determination of further safety-relevant parameters such as a degree of discard, e.g., 100% discard.

[0065] The flexural fatigue strength is evaluated in accordance with DIN ISO 4309 (version: 06 / 2013).

[0066] The inventor has surprisingly discovered that the service life and a certain degree of discard maturity can be increased by core rope inner strands embedded in a plastic matrix, wherein only the core rope inner strands are completely embedded in the plastic matrix, compared to a wire rope of the same design without core rope inner strands embedded in a plastic matrix.

[0067] To determine the percentage increase, the discard maturity A and the service life L 1 are determined using the aforementioned test for a first wire rope D with a diameter d without core rope inner strands embedded in a matrix, whereby these determined values ​​for the discard maturity A 1 and the service life L 1 of the first wire rope D 1 each correspond to 100% and each is a reference value.

[0068] Subsequently, the discard criteria A2 and the service life L2 are determined for a second wire rope D2 with a diameter d using the aforementioned test, wherein this wire rope D2 has core strands embedded in a plastic matrix. The values ​​for the discard criteria A2 and the service life L2 of the wire rope D2 are then compared to the respective values ​​for the discard criteria A1 and the service life L1 of the first rope D1. These ratios correspond to the relative service life and the relative discard criteria. According to the invention, the ratio L2 / L1 is between 1.03 and 1.40.

[0069] Similar increases were found for the discard maturity, meaning that the ratio A 2 / A 1 is also between 1.03 and 1.40.

[0070] The discard maturity A 1 , A 2 can be 100% discard maturity, or a lower degree of discard maturity.

[0071] Advantageously, the non-rotating wire rope has an actual breaking force F m that is between 15% and 50% higher than the actual breaking force F m of a wire rope of the same type whose core rope is not compacted.

[0072] The inventor recognized that a compression of the core rope results in an increase in the actual breaking strength F m.

[0073] In one embodiment of the invention, the non-rotating wire rope has a service life L and / or a discard maturity A at a nominal tensile stress σ Z of 127 N / mm 2< ± 10 N / mm 2< which is between 3% and 45% higher than the service life L and / or discard maturity A of a wire rope of the same type whose core rope is not compacted.

[0074] The inventor has determined that a compression of the core rope results in an increase in service life L and discard maturity A.

[0075] Advantageously, the core rope inner strands and the core rope outer strands are designed as complete strands, in which no wire is omitted to create a cavity for receiving the plastic forming the plastic matrix.

[0076] Advantageously, a wire rope with high fatigue strength is created, which also has a particularly high fill factor compared to rotation-free wire ropes known from the prior art.

[0077] A method according to the invention for producing a rotation-free wire rope, in which a first core rope inner strand is surrounded with a plastic sheathing and is stranded at a stranding point of a stranding device with further core rope inner strands and core rope outer strands to form a core rope in such a way that only the core rope inner strands are introduced into a plastic matrix, is characterized in that outer strands are stranded with the core rope to form the rotation-free wire rope.

[0078] The plastic sheathing is designed such that the subsequent inner strands of the core rope are completely embedded within it in a circumferential direction at the stranding point. In a manufactured core rope, the plastic sheathing of the first inner strand forms the plastic matrix.

[0079] In one embodiment of the inventive method, the core rope is compacted before being stranded with the outer strands to form the rotation-free wire rope.

[0080] A lifting device according to the invention with a drum drive, in particular a crawler crane, has a rotation-free wire rope according to the invention, which is designed as a running rope.

[0081] A running rope is a rope which, when used as intended, for example as a load rope of a lifting device, is deflected by pulleys or wound onto or unwound from a rope drum.

[0082] The invention is explained in more detail below with reference to exemplary embodiments and the accompanying drawings relating to these embodiments. The drawings show: Fig. 1 a-d Several embodiments of a rotation-free wire rope in cross-section, wherein the embodiments according to Figur 1b and Figur 1d not covered by the claims, Fig. 2 a, relative actual breaking strength, relative service life and relative discard maturity for various wire ropes D 1 , D 2 , D 1' and D 2' .

[0083] A in Fig. 1a The rotation-free wire rope 1 shown schematically in cross-section is designed as a round strand rope and comprises a core rope 2 designed as a parallel lay rope and a single outer strand layer 3, which has sixteen outer strands 4, wherein the outer strands 4 are applied directly to the core rope 2.

[0084] The core rope is designed as a 1+8+8 wire rope and has a first, innermost core rope inner strand 5, which is surrounded by eight further core rope inner strands 6. A core rope outer strand layer 7 comprises a total of eight core rope outer strands 8.

[0085] In this embodiment, the core rope inner strands 5, 6 and the core rope outer strands 8 are compacted.

[0086] The core rope inner strands 5, 6 are embedded in a plastic matrix 9 made of polypropylene (PP) in such a way that all core rope inner strands 5, 6 are completely surrounded by the plastic matrix 9 in the circumferential direction.

[0087] The core rope outer strands 8 are embedded in the plastic matrix 9 in the core rope outer strand areas 10 facing the core rope inner strands 5, 6; that is, they are embedded only in certain areas. The core rope outer strand areas 101 facing away from the core rope outer strands 8 are not embedded in the plastic matrix 9.

[0088] For the sake of simplicity, the core rope outer strand areas 10, 101 are separated from each other in the exemplary embodiments by a dashed circle line 102.

[0089] A in Fig. 1b The cross-section of the rotation-free wire rope 1, shown schematically, differs from the one in Fig. 1a This is demonstrated by the fact that it comprises a covering 11 made of a plastic material, which completely encloses the core rope 2 in a circumferential direction in the manner of a sheath. An outer strand layer 3 is applied directly to the covering 11.

[0090] The covering 11 can be designed as a further plastic matrix that encloses core rope outer strand areas 101 facing away from the core rope inner strands 5, 6 and into which outer strand areas of the outer strands 4 facing the core rope 2 are inserted.

[0091] The dashed circle 102 forms the following in Fig. 1 b The wire rope 1 shown simultaneously forms a separating plane along which the plastic matrix 10 and the covering 11 are separated from each other, i.e., they lie loosely against each other without being connected to each other.

[0092] The core rope 2 of the in Fig. 1a und 1b The wire rope shown (1) is not compacted.

[0093] A in Fig. 1c The rotation-free wire rope 1, shown schematically in cross-section, differs from the one in Fig. 1a shown by the fact that a core rope 2 is compacted, thereby creating a smooth and flat core rope surface 12.

[0094] A in Fig. 1d The rotation-free wire rope 1, shown schematically in cross-section, differs from the one in Fig. 1b shown by the fact that a core rope 2 is compacted, thereby creating a smooth and flat core rope surface 12.

[0095] For the sake of clarity, in Fig. 1a-d not all outer strands 4, core rope inner strands 6, core rope outer strands 8 and core rope outer strand areas 10 facing the core rope inner strands 5, 6 and core rope outer strand areas 101 facing away from the core rope inner strands 5, 6 are provided with a reference sign.

[0096] The in Fig. 1a bis 1d The non-rotating wire ropes 1 shown are particularly suitable for use as running ropes in a lifting device with a drum drive, in particular a crane such as a crawler crane, a mobile crane, a deck crane of a ship, a ship unloading crane or a tower crane.

[0097] It will now be on Fig. 2 Reference is made where identical or equivalent parts are used with the same reference number as in Fig. 1 are designated and the letter a is appended to the relevant reference number.

[0098] All for determining the in Fig. 2 a , bThe wire ropes D1, D2, D1' and D2' used for the wire rope properties shown have a core rope of construction 1+8+8, wherein the core rope inner strands and core rope outer strands are compacted before being stranded to form the core rope. A single outer strand layer comprises 16 outer strands of construction 1+6, that is, a single core wire ("1") is stranded with six ("+6") surrounding wires to form the outer strand.

[0099] To form the respective wire rope D 1 , D 2 , D 1' and D 2', the respective core rope and the 16 outer strands are stranded together.

[0100] In this embodiment, the rope diameter of each wire rope D 1 , D 2 , D 1' and D 2' is 22 mm.

[0101] All core rope strands were compacted before being stranded together to form a core rope.

[0102] Wire rope D2 differs from wire rope D1 in that one core strand of wire rope D2 is compacted. Neither wire rope D1 nor D2 has core strands embedded in a plastic matrix.

[0103] The wire rope D 1' differs from the wire rope D 1 in that only the inner strands of the core rope of the wire rope D 1' are embedded in a plastic matrix. Neither the wire ropes D 1 nor D 1' have a compacted core rope.

[0104] The wire rope D 2' differs from the wire rope D 2 in that only the inner strands of the core rope of the wire rope D 2' are embedded in a plastic matrix. Both wire ropes D 2 and D 2' have a compacted core rope.

[0105] In neither of the wire ropes D 1' and D 2' are the core rope outer strands fully embedded in the plastic matrix in which the core rope inner strands are embedded, but only the core rope outer strand areas facing the core rope inner strands in the manner shown in Fig. 1a , c They are shown surrounded by plastic.

[0106] The outer strands are applied directly to the core rope, meaning the core rope outer strands and the outer strands lie directly against each other.

[0107] In a Fig. 2a The diagram shown depicts the relative actual breaking strength for the four wire ropes D 1 , D 2 , D 1' and D 2'.

[0108] The breaking strength of wire rope D 1 is F m1 , that of wire rope D 2 is F m2 , that of wire rope D 1' is F m1' and that of wire rope D 2 is F m2' .

[0109] The relative actual breaking strength for the wire rope D 1 is 100 % (= ratio F m1 to F m1 ), that is a reference value.

[0110] To determine the relative breaking strength of the wire rope D 2, the ratio F m2 to F m1 is calculated.

[0111] To determine the relative breaking strength of the wire rope D 1', the ratio F m1' to F m1 is formed.

[0112] To determine the relative breaking strength of the wire rope D 2', the ratio F m2' to F m1 is calculated.

[0113] By embedding core rope inner strands, i.e., exclusively core rope inner strands, in a polymer matrix, an increase in the actual breaking strength Fm1' of the wire rope D1' by 8% compared to that of the wire rope D1 (Fm1) is possible. Surprisingly, the inventor has found that, contrary to the prior art, complete embedding of a core rope in a polymer matrix is ​​not necessary; rather, complete embedding of core rope inner strands is sufficient.

[0114] By compacting the core rope, it is possible to increase the actual breaking strength F m2 of the wire rope D 2 by 31% compared to that of the wire rope D 1 (F m1 ).

[0115] By means of core rope inner strands embedded in a plastic matrix, whereby only the core rope inner strands are completely embedded in the plastic matrix, in combination with a compaction of the core rope, an increase in the actual breaking strength F m2' of the wire rope D 2' by 41% compared to that of the wire rope D 1 (F m1 ) is possible.

[0116] In a Fig. 2b The diagram shows the relative service life and the relative discard criteria for the four wire ropes D1, D2, D1' and D2. In this embodiment, the discard criteria are the so-called 100% discard criteria, meaning that the wire rope must be replaced for the continued safe operation of a device guiding the wire rope.

[0117] The service life of wire rope D 1 is L 1 , that of wire rope D 2 is L 2 , that of wire rope D 1' is L 1' and that of wire rope D 2' is L 2' .

[0118] The 100% discard maturity of wire rope D 1 is A 1 , that of wire rope D 2 is A 2 , that of wire rope D 1' is A , and that of wire rope D 2' is A 2' .

[0119] The relative service life of wire rope D1 is 100%, while its relative 100% discard maturity A is 80%. These are reference values ​​derived by calculating the ratios A1 to A1 and L1 to L1, respectively.

[0120] To determine the relative service life of wire rope D2, the ratio L2 to L1 is calculated. The relative service lives of the other wire ropes are determined analogously with respect to the service life L1 of wire rope D1.

[0121] To determine the relative 100% discard maturity of wire rope D2, the ratio A2 to A1 is calculated. The relative 100% discard maturity of the other wire ropes is determined analogously with respect to the 100% discard maturity A1 of wire rope D1.

[0122] For wire rope D 1, an increase in service life L 1' of 6% was determined compared to that of wire rope D 1, while an increase in 100% discard maturity A 1' from 80% to 84% was determined.

[0123] For wire rope D 2, an increase in service life L 2 of 13% was determined compared to that of wire rope D 1, while an increase in 100% discard maturity A 2 from 80% to 90% was determined.

[0124] For the wire rope D 2', an increase in service life L 2' of 38% was determined compared to that of the wire rope D 1, while an increase in discard maturity A 2' from 80% to 110% was determined.

[0125] Overall, the wire ropes D 1' and D 2' show a significant increase in the relative actual breaking strength, the relative service life and the relative 100% discard maturity.

[0126] Surprisingly, despite the increase in the actual breaking strength Fm, a significant increase in service life and 100% discard criterion was observed. This is contrary to the expectations of a rope expert, as an increase in the actual breaking strength Fm usually leads to a decrease in service life and a decrease in 100% discard criterion.

[0127] It was also found that a further improvement of the aforementioned properties is possible if the wire rope additionally has a covering surrounding the core rope that has no connection to a plastic matrix in which only the core rope inner strands are embedded.

Claims

1. Rotation-resistant wire rope (1; D1', D2'), in particular rotation-resistant round strand rope, which has a core rope (2) and outer strands (4) surrounding the core rope, said outer strands forming a single outer strand layer (3), wherein the core rope (2) comprises several core rope inner strands (5, 6) which are embedded into a plastic matrix (9) and which are surrounded by core rope outer strands (8) that form a core rope outer strand layer (7), characterized in that only the several core rope inner strands (5, 6) of the core rope (2) are completely embedded into the plastic matrix (9).

2. Rotation-resistant wire rope according to claim 1, characterized in that the core rope outer strands (8), which are only partially embedded into the plastic matrix (10), abut directly against the outer strands (4) with core rope outer strand regions (101) facing away from the core rope inner strands (5, 6).

3. Rotation-resistant wire rope according to claim 1 or 2, characterized in that the core rope outer strands (8) of the core rope (2) are embedded into the plastic matrix (9) only with core rope outer strand regions (10) facing the core rope inner strands (5, 6), and core rope outer strand regions (101) facing away from the core rope inner strands (5, 6) are not embedded into the plastic matrix.

4. Rotation-resistant wire rope according to one of claims 1 to 3, characterized in that adjacent core rope outer strands (8) are separated from one another by the plastic matrix (9), which extends from the core rope inner strands (5, 6) in radial direction of the wire rope (1) to the core rope outer strands (8), wherein the plastic matrix (10) extends in radial direction of the core rope only to such an extent that core rope outer strand regions (101) facing away from the core rope inner strands (5, 6) are not embedded into the plastic matrix.

5. Rotation-resistant wire rope according to claim 1, characterized in that the core rope (2) is compacted.

6. Rotation-resistant wire rope according to one of claims 1 to 5, characterized in that the outer strands (4) are applied directly onto the core rope (2).

7. Rotation-resistant wire rope according to one of claims 1 to 6, characterized in that the core rope (2) is a parallel lay rope.

8. Rotation-resistant wire rope according to claim 1, <b>characterized in that the rotation-resistant wire rope (1; D1') has an actual breaking force Fm which is between 3% and 45% higher than the actual breaking force Fm of a wire rope (D1) of the same construction in which core rope inner strands are not embedded into a plastic matrix.

9. Rotation-resistant wire rope according to claim 1, <b>characterized in that the rotation-resistant wire rope (1; D1') at a nominal tensile stress σZ of 127 N / mm2 + / - 10 N / mm2 has a service life L and / or a discard A in bending cycles which is between 3% and 40% higher than the service life L and / or discard A of a wire rope (D1) of the same construction in which core rope inner strands are not embedded into a plastic matrix.

10. Rotation-resistant wire rope according to claim 1 and claim 5, <b>characterized in that the rotation-resistant wire rope (1; D2') has an actual breaking force Fm which is between 15% and 50% higher than the actual breaking force Fm of a wire rope (D1') of the same construction whose core rope is not compacted.

11. Rotation-resistant wire rope according to claim 1 and claim 5, <b>characterized in that the rotation-resistant wire rope (1; D2') at a nominal tensile stress σZ of 127 N / mm2 + / - 10 N / mm2 has a service life L and / or a discard A which is between 3% and 45% higher than the service life L and / or discard A of a wire rope (D1') of the same construction whose core rope is not compacted.

12. Rotation-resistant wire rope according to one of claims 1 to 11, characterized in that the core rope inner strands (5, 6) and the core rope outer strands (8) are designed as complete strands in which no wire is omitted in order to create a cavity for receiving plastic forming the plastic matrix (10).

13. Method for producing a rotation-resistant wire rope (1; D1', D2'), in particular a rotation-resistant round strand rope, in which a first core rope inner strand (5) is surrounded with a plastic sheathing and is stranded at a stranding point of a stranding device with further core rope inner strands (6) and core rope outer strands (8) to form a core rope (2), and outer strands (4) are stranded with the core rope (2) to form the rotation-resistant wire rope (1; D1', D2'), characterized in that exclusively the core rope inner strands (6) are completely embedded into a plastic matrix.

14. Method according to claim 13, characterized in that the core rope (2) is compacted before stranding with the outer strands (4) to form the rotation-resistant wire rope (1; D1', D2').

15. Hoisting apparatus with a drum drive, in particular crawler crane, which has a rotation-resistant wire rope (1; D1', D2') according to one of claims 1 to 12, wherein the rotation-resistant wire rope (1; D1', D2') is designed as a running rope.

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