Helical endless splice

Abstract

The present invention relates to an end-for-end splice for joining two ropes. The splice includes a helical section and a tapered section, where the strands of one rope are inserted into the other rope in a helical pattern. Furthermore, in the tapered section, the inserted strands have a decreasing volume away from the center of the splice. This splice configuration has been found to result in a relatively small diameter and excellent CBOS performance.

Description

[Technical Field]

[0001] The present invention is in the field of splices for synthetic ropes. In particular, the present invention is directed to end-to-end splices for synthetic ropes used in dynamic cyclic bending over sheave (CBOS) type applications. [Background technology]

[0002] Synthetic ropes (i.e., ropes based on synthetic polymer fibers) are used in the field of hoisting and lifting under a variety of conditions. Due to their relatively light weight compared to their predecessor, steel wire rope (SWR), but comparable mechanical and strength properties, synthetic ropes can be advantageously used to lift loads over long distances, from hundreds of meters to several kilometers. Synthetic ropes can be used in marine and offshore applications, such as deep-sea mooring and deep-sea lifting. In these applications, the ropes are subject to wear and other damage. However, completely replacing a partially worn or damaged rope is not always economically attractive; instead, the worn or damaged section of the rope must be removed and the remaining good section of the rope must be spliced ​​back together. However, because ropes are typically run over sheaves and collected on drums, splices must meet special requirements. For example, the diameter of the splice must not be too large compared to the diameter of the original rope, because otherwise the splice would not run smoothly over the sheaves and on the drum where the rope is collected. The splice should also have good life as it travels over the sheave, without running loose or becoming damaged. Furthermore, because splicing typically must be done on-site, for example, on board an offshore vessel or platform, the splice should not be too long, otherwise splicing would become too complicated or impossible. Ideally, the splicing process should be as simple as possible.

[0003] Various end-for-end splices (also called endless splices) for synthetic ropes are known in the art. WO 2013 / 134033 describes a splice having helical and tucked strand sections for connecting a first rope to a second rope, the splice having a helical section and a tucked section in which strands of either rope extend longitudinally and pass under and over strands of the other rope.

[0004] Another known end-for-end splice is referred to in the art as the Hakama splice. In this splice, a pair of two unbraided strands of rope are inserted longitudinally under and over the intersection of two adjacent strands of different lay directions (the "X" of the rope). Disadvantages of the Hakama splice are its relatively large diameter (approximately 1.6 to 2.0 times its nominal diameter) and the physically difficult method of manufacturing it.

[0005] The ropes in both the splicing procedure of WO 2013 / 134033 and the Hakama splice must be the same diameter to be splicable. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] International Publication No. 2013 / 134033 Summary of the Invention [Problem to be solved by the invention]

[0007] SUMMARY OF THE INVENTION It is an object of the present invention to provide an improved splice that addresses one or more of the above-mentioned drawbacks. [Means for solving the problem]

[0008] The inventors have discovered that this objective can be met by providing a splice comprising a helical section and a tapered section. In both sections, the strands of one rope are inserted into the other rope in a helical pattern. Furthermore, in the tapered section, the inserted strands decrease in volume away from the center of the splice. This splice configuration has been found to result in a relatively small diameter and excellent CBOS performance. Also, the splice can be made relatively short without this configuration compromising the mechanical performance of the splice. Finally, a splice according to the present invention allows for the joining of ropes of different diameters with excellent efficiency.

[0009] Accordingly, the present invention provides a spliced ​​synthetic rope comprising: a first rope comprising a first plurality of strands; a second rope comprising a second plurality of strands; and A splice for connecting a first rope and a second rope, the splice comprising a splice center, the splice comprising at least a helical section comprising a first helical section and a second helical section, and two tapered sections disposed on either side of the helical section and at an end of either side of the splice; the first helical section comprises one or more strands of the first rope inserted into a helical pattern in the second rope, and the second helical section comprises one or more strands of the second rope inserted into a helical pattern in the first rope; The tapered section is directed to a spliced ​​composite rope comprising a first tapered section and a second tapered section, each comprising one or more strands of a first rope and a second rope inserted into the second rope and the first rope in a helical pattern, the strands (i.e., the strands inserted into the tapered section) decreasing in volume in a direction away from the splice center.

[0010] The splice center is the central spot of the splice. In a typical embodiment, the splice center is located at the center of the helical section and between the first and second helical sections. The first helical section can then be positioned directly adjacent to the first tapered section, while the second helical section can be positioned directly adjacent to the second tapered section. It will be appreciated that the splice can also include additional sections. These additional sections may be between one or both of the helical and tapered sections. However, preferably, the splice includes only the helical and tapered sections.

[0011] In a preferred embodiment, the strands inserted into the helical pattern are bundled in sets of two or more, typically two adjacent strands. In a typical embodiment, two or more adjacent strands are bundled, preferably twisted, with a new set of strands and then inserted into the other rope. This preferably applies to all strands in the helical and tapered sections. Typically, the strands of a composite rope are based on multiple yarns twisted in a specific direction (also called twist direction), e.g., left-handed or right-handed. In a further preferred embodiment, the bundled strand sets are twisted in the same twist direction as the orientation of the individual strands. Thus, for example, two adjacent left-handed twist-oriented sets of strands of a first rope may be bundled and twisted in a left-handed twist direction before being inserted into a second rope in a helical pattern. This is somewhat similar to the structure of a conventional Lang twist. It is further preferred that the strands are divided into equal left-handed and right-handed twist-oriented sets.

[0012] The helical and tapered sections comprise strands interleaved in a helical pattern. Preferably, essentially all of the strands in the helical and tapered sections are interleaved in a helical pattern, and even more preferably, essentially all of the strands throughout the splice are interleaved in a helical pattern. Interleaving in a helical pattern means that, when the other rope has a braided structure, the strands are interleaved helically or spirally under and over the strands of the other rope. When the other rope has a twisted structure, interleaving in a helical pattern means that the strands are twisted helically or spirally next to the strands of the other rope.

[0013] In the next few paragraphs, we will explain the splice insertion pattern by way of example, by inserting a strand of a first rope into a second rope. However, it will be understood that the same principles apply to inserting a strand of a second rope into a first rope. Indeed, in preferred embodiments, the splice structure is essentially symmetrical, i.e., there is preferably an essential mirror symmetry of the splice at the center of the splice, which allows for more efficient load transfer and lower stress concentrations in the splice.

[0014] In typical embodiments where the second rope is a braided rope, one or more strands of the first rope are threaded into the first helical section in a helical pattern with at least 10, preferably at least 15, helical tucks above and below the strands of the second rope. In the first tapered section, one or more strands of the first rope are typically threaded into the first helical section in a helical pattern with at least 5, preferably at least 7, helical tucks above and below the strands of the second rope.

[0015] The number of strands of the second rope that are inserted above and below each strand of the first rope can be selected as appropriate. Preferably, this number is the same for all tucks of a particular strand of the first rope inserted in the spiral section. In fact, more preferably, it is the same for all strands of the first rope in the spiral section. In the most preferred embodiment, the strands of the first rope are inserted into the second rope in as natural a manner as possible, which means following the original structure as closely as possible. Thus, if the original structure of the second rope is a "two-over, two-under structure," the number of strands of the second rope that the strands of the first rope are inserted below and above will most preferably be the same: two above and two below. In other words, in certain embodiments, the first rope and the second rope have the same original structural pattern (e.g., braided or twisted pattern), and one or more strands of the first rope and the second rope are inserted into the spiral and / or tapered sections of the second rope and the first rope, respectively, and are twisted with adjacent strands of the second rope and the first rope, respectively, thereby following the original structural patterns of the second rope and the first rope, respectively. The strands inserted into the spiral and / or tapered sections are preferably positioned essentially next to (i.e., not on top of) adjacent strands of the second rope. Thus, the strands are preferably inserted within the valleys (or gaps) between the structural strands of the second rope. Thus, positioning the strands essentially adjacent to adjacent strands means that these strands are positioned as much as possible within the original structure of the second rope, but not above it. Placing a strand over an adjacent strand increases the diameter of the particular splice section.

[0016] The orientation of the helical pattern in which the strands of the first rope are inserted into the second rope in the helical section may depend on the twist orientation of the yarn, and thus optionally on the twist of the set of strands if the strands are bundled and twisted. Preferably, the orientation of the helical pattern is opposite to the twist orientation of the yarn and any twist orientation of the bundle of strands. Thus, for example, two adjacent left-handed twisted strand sets of the first rope, optionally bundled and twisted in a left-handed twist orientation, are preferably inserted into the right-handed helical pattern of the second rope.

[0017] Advantageously, when the total number of strands of a rope is divided into equal sets of left- and right-hand oriented bundles and these bundles are inserted into the other rope with different lay directions (i.e., left-hand oriented bundles are inserted into right-hand lay directions, and vice versa), several new intersections are formed between the inserted strands, improving the coefficient of friction between these strands within the splice. This can reduce the overall length of the splice required compared to a conventional splice. Furthermore, the bundled strands also improve the overall coefficient of friction between these strands within the splice, further reducing the length of the splice compared to a conventional splice. Furthermore, the bundled strands also reduce the volume of the two separate strands, resulting in a thinner overall splice.

[0018] The tapered section is preferably configured similarly to the helical section. Preferably, the only difference is that the tapered section has a diameter that decreases in a direction away from the splice center, while the helical section has an essentially constant diameter. Accordingly, the inserts as described hereinabove for the first helical section also apply mutatis mutandis to the first tapered section and also to the second tapered section.

[0019] The first and second tapered sections are typically provided by reducing the strand volume by at least 1 / 25 of the original strand volume in several stages. The reduction in strand volume can be achieved by cutting away a portion of each strand inserted into the rope. In a typical embodiment, the strand volume is reduced by at least 1 / 10 of the original strand volume in at least two stages, more preferably by 1 / 3 of the original volume in two stages.

[0020] The first and second ropes may be the same or different in terms of construction pattern, rope diameter, and material. Advantageously, the present invention allows for splicing of ropes with excellent efficiency and performance, even if the ropes are different.

[0021] In a specific embodiment, a first rope having a diameter d1 is spliced ​​with a second rope having a diameter d2, where d1 and d2 are different. As used herein, the rope diameter refers to the nominal diameter of the rope and means the diameter of a circumscribed circle surrounding all strands of the rope. In principle, the difference between d1 and d2 that is permissible for a rope to be splicable according to the present invention is not limited. If the rope diameters differ by more than about 20% (based on the thickest rope, i.e., if d1 > d2, then (d1 - d2) / d1 x 100% > about 20%), it may be preferable to adjust the volume of one of the ropes. On the other hand, if the diameters of both ropes are less than about 20% based on the thickest rope, the ropes can generally be spliced ​​without adjusting the volume of either rope.

[0022] Adjusting the volume of the rope can be achieved by cutting, preferably tapering, the rope. In embodiments where the thickest rope (i.e., the rope with the largest diameter) is also the strongest rope (in terms of breaking strength), the volume of the thickest rope is adjusted. Typically, the volume of the rope is adjusted to match the strength of the thinnest rope (i.e., the rope with the smallest diameter). If both ropes are based on the same material and similar construction (e.g., both braided or both twisted), strength-matching the ropes will result in the ropes having approximately the same diameter. As used herein, "strength-matched ropes" means that the ropes have similar strengths and that the difference in breaking strength between the ropes after adjustment is smaller than before adjustment. Preferably, matching means that the ropes have a difference in breaking strength of less than about 80%, preferably less than 50%, more preferably less than 20%, and most preferably less than about 10%, based on the strongest rope.

[0023] In embodiments where the thickest rope is the weakest rope, it may be preferable to limit or eliminate volume adjustment. In embodiments where the ropes differ substantially in diameter (e.g., by more than 20% based on the thickest rope) but sufficient volume adjustment is not desirable due to the resulting rope strength mismatch, it may be preferable to use one or more intermediate ropes that can overcome the difference in diameter of both ropes. For example, if ropes having a 40% difference in diameter (based on the thickest rope) are to be spliced ​​but volume adjustment of the thickest rope is not desirable, an intermediate rope having a 20% difference between both ropes (based on the thickest rope) can be used to bridge the ropes. The intermediate rope can be spliced ​​to the rope at both ends using the splicing method of the present invention (i.e., including the spiral and tapered sections described herein).

[0024] The first and second ropes may be independently braided or twisted. Preferably, both ropes are braided. Furthermore, the first and second ropes may have the same or different numbers of strands. Preferably, both ropes have the same number of strands.

[0025] In embodiments in which the original structure of the first rope and the second rope is a stranded rope, the stand of the first rope preferably follows the stranded structure of the second rope in the first spiral section and the first tapered section, and vice versa. In embodiments in which the original structure of the first rope is a braid but the second rope is a stranded rope, the stand of the first rope preferably follows the stranded structure of the second rope in the first spiral section and the first tapered section, while the stand of the second rope preferably follows the braided structure of the first rope in the second spiral section and the second tapered section.

[0026] In embodiments in which the first and second ropes have different numbers of strands, the number of strands in both ropes of the splice is preferably adjusted to a common factor. By common factor, we mean a common mathematical factor, i.e., a number into which the number of strands in both ropes is divided, leaving no remainder in either rope. For example, if the first rope has 12 strands and the second rope has 8 strands, both ropes have common factors of 2 and 4. In this embodiment, the strands of the first rope can be bundled into four sets of three bundled strands, while the strands of the second rope can be bundled into four sets of two bundled strands. Thus, the bundled strand sets of both ropes can be interleaved while following the rope's natural structural pattern. Similarly, if the first rope is a twisted rope with six strands wound around a core and the second rope is a braided rope with 12 strands, the common factors are 2 and 6. Six strands of the first rope can remain unbundled, while 12 strands of the second rope can be bundled into six sets of two bundled strands. The cores can be included separately, spliced ​​as described herein below. Also, as also described herein, the bundled strands are preferably adjacent strands, preferably bundled and twisted.

[0027] Preferably, the common factor is a suitable factor, meaning sufficient to allow multiple tucks and multiple crossings between the interleaved strands. If the ropes have more than one common factor, the highest factor is preferably selected for the splice. Furthermore, a factor of 2 is generally not suitable. If the first and second ropes do not have a suitable common factor, the strands of one or both ropes in the splice can be unwound to the yarn or substand level and reassembled into new strands that allow for a common factor. For example, if the first rope is a twisted rope with six strands twisted around a core and the second rope is a braided rope with eight strands, the ropes have a common factor of only 2. In such an embodiment, the six strands of the first rope can be unwound to the yarn level and reassembled into, for example, eight or four new strands, and the new strands can then be directly inserted into the second rope (i.e., without bundling). Similarly, the eight strands of the second rope can be unraveled down to the thread level and reconstructed into, for example, six or three strands, which can then be inserted directly into the first rope.

[0028] The first rope and the second rope can each independently include a core around which each strand is constructed. In typical rope construction, the core has no or very limited load-bearing capacity. Therefore, the insertion of the core is less important than the insertion of the strands. The core can be included in the splice by splitting the core threads across the strands of the rope, by inserting the entire core into the structure of the other rope (helically and / or longitudinally), or, if both ropes include a core, the cores can be spliced ​​separately.

[0029] Advantageously, a splice according to the present invention is relatively easy to construct due to its relatively short length. The splice can have a total splice length of, for example, less than 240 times the diameter of the first rope and / or the second rope. However, it can also be less than 180 times this diameter. For reasons of ease of construction, the splice is preferably as short as possible, for example, less than 150 times the diameter of the first rope and / or the second rope, for example, not more than about 120 times. For reasons of strength, however, the splice preferably has a minimum length of 100 times the diameter of the first rope and / or the second rope, and more preferably, the splice has a length greater than 120 times the diameter of the first rope and / or the second rope. Thus, in a preferred embodiment, the splice has a total splice length in the range of 100 to 240, more preferably 120 to 180, such as about 150 times the diameter of the first rope and / or the second rope.

[0030] The helical section is preferably longer than the combined length of the tapered sections. Typically, the ratio of the length of the helical section to the length of the tapered section is greater than 1:1, preferably greater than 3:2, and more preferably 2:1 or greater.

[0031] In typical embodiments, the first and / or second helical sections each independently have a total splice length of less than 80 times the diameter of the first and / or second rope. Preferably, the first and / or second helical sections each independently have a total splice length of less than 60 times, more preferably less than 50 times, and most preferably about 40 times the diameter of the first and / or second rope.

[0032] Advantageously, the splice according to the invention has a relatively small diameter. Typically, the diameter is at most 1.7 times less than the diameter of the rope having the largest diameter (and thus both ropes, if the first rope and the second rope have the same diameter). In a preferred embodiment, the diameter of the splice is at most 1.6 times less than the diameter of the rope having the largest diameter (and thus both ropes, if the first rope and the second rope have the same diameter), for example at most in the range of 1.5 to 1.55 times.

[0033] In a typical embodiment, the first and / or second tapered sections each independently have a total splice length that is less than 40 times, preferably less than 30 times, more preferably less than 25 times, and most preferably about 20 times the diameter of the first and / or second rope.

[0034] The splice according to the invention is particularly suitable for splicing synthetic ropes with ropes based on high-performance fibers. High-performance fibers are known in the art for their high tenacity and low elongation (elongation at break). High-performance fibers preferably have a tenacity of at least 15 g / denier, more preferably at least 20 g / denier. The tenacities of commonly used fibers are known in the art; see, for example, Handbook of Fiber Rope Technology by H.A.M. McKenna, J.W.S. Shearle and N. O'Hear, 2004, Woodhead Publishing Ltd. High-performance fibers are also preferably characterized by a low elongation at break (typically less than 3.5%), which is another desirable property for application in hoisting ropes, especially deep-sea ropes.

[0035] Examples of high performance fibers are fibers based on ultra-high molecular weight polyethylene (UHMWPE, available for example under the trade names Dyneema™ and Spectra™), (para-)aramid (available for example under the trade names Twaron™, Kevlar™ and Technora™), liquid crystalline aromatic polyesters (available for example under the trade name Vectran™), carbon fibers, etc. The fibers may further be provided with an overlay finish, as is the case for example with Dyneema™ fibers with XBO available from Avient Corporation, USA.

[0036] The splice according to the present invention is particularly suitable for repairing damaged ropes in the field. Thus, in certain embodiments, the first rope and the second rope have the same number of strands. In other embodiments, the first rope and the second rope have a different number of strands.

[0037] Preferably, the first rope and the second rope each comprise 4 to 24 strands, preferably 12 strands. Each of these strands may be based directly on the (twisted) yarn, but may also be based on sub-strands (e.g., 3 strands each). Thus, the first rope and the second rope may be, for example, a 12-strand rope or a 12 x 3-strand rope. Such ropes are commercially available from Lankhorst Euronete Portugal, SA as LANKO® DEEP-TW and LANKO® DEEP AHC. The ropes may also comprise a jacket, but this is not preferred.

[0038] A further aspect of the present invention is directed to a method for providing a spliced ​​synthetic rope, the method comprising: i. aligning a first rope and a second rope and determining a splice center; ii. preparing the tails of the first rope and the second rope for splicing, the preparing step including unwinding the tails to the center of the splice; iii. providing a first helical section by inserting one or more strands of the first rope into the second rope in a helical pattern; iv. providing a second helical section by inserting one or more stands of a second rope into the first rope in a helical pattern; v. providing a first tapered section by inserting one or more strands of the first rope into the second rope in a spiral pattern and by cutting away a portion of the strand volume during said inserting; vi. Providing a second tapered section by inserting one or more strands of the second rope into the first rope in a spiral pattern and by cutting away a portion of the strand volume during said inserting.

[0039] For clarity, the chronological order of steps (ii) through (v) need not necessarily be in the order described above. Typically, both ropes are untied first, and then both halves of the splice are constructed, although it will be understood that one half, or a portion thereof, may be constructed first before the other rope is untied. Furthermore, typically, one half of the splice is constructed first, followed by the other. Thus, a typical chronological order would be step ii, followed by steps iii and v, followed by steps iv and vi, or step ii, followed by steps iv and vi, followed by steps iii and v.

[0040] In step ii, the tails of the first rope and the second rope are typically unwound to the rope strand level, meaning that the strands are not individually unwound into separate threads or sub-strands. In certain embodiments where the first rope and the second rope have several strands that lack a suitable common factor, as described herein above, step ii comprises unwounding the tails of the first rope and the second rope to the thread or sub-strand level, followed by reassembling the thread into a new strand. As used herein, unwounding to the thread level means that each strand is unwound individually. It will be understood that unwinding can comprise unraveling, unwinding, and / or untwisting, depending on the original structure of the particular rope.

[0041] If the diameters of the first rope and the second rope are different, step ii may further comprise adjusting the volume of one rope, typically the thickest rope, to match the strength of the other rope, preferably the diameter of the other rope, as described herein above.

[0042] In a preferred embodiment, step iii comprises: iiia. bundling and optionally twisting two or more adjacent strands of a first rope, preferably twisting in the same twist direction as the individual strand orientations; iiib. twisting the bundled and optionally twisted strands into a second rope in a helical pattern.

[0043] Similarly, for step iv, preferably this is iva. bundling and optionally twisting two or more adjacent strands of the second rope, preferably twisting in the same twist direction as the individual strand orientations; ivb. twisting the bundled and optionally twisted strands into a first rope in a helical pattern.

[0044] 1-6 illustrate a particular embodiment of a method for providing a spice rope having a first rope and a second rope of 12 strands. [Brief explanation of the drawings]

[0045] [Figure 1A] 1 illustrates a specific embodiment of a method for providing a spice rope having a first rope and a second rope of 12 strands. [Figure 1B] 1 illustrates a specific embodiment of a method for providing a spice rope having a first rope and a second rope of 12 strands. [Figure 2A] 1 illustrates a specific embodiment of a method for providing a spice rope having a first rope and a second rope of 12 strands. [Figure 2B] 1 illustrates a specific embodiment of a method for providing a spice rope having a first rope and a second rope of 12 strands. [Figure 3A] 1 illustrates a specific embodiment of a method for providing a spice rope having a first rope and a second rope of 12 strands. [Figure 3B] 1 illustrates a specific embodiment of a method for providing a spice rope having a first rope and a second rope of 12 strands. [Figure 3C] 1 illustrates a specific embodiment of a method for providing a spice rope having a first rope and a second rope of 12 strands. [Figure 4A] 1 illustrates a specific embodiment of a method for providing a spice rope having a first rope and a second rope of 12 strands. [Figure 4B] 1 illustrates a specific embodiment of a method for providing a spice rope having a first rope and a second rope of 12 strands. [Figure 4C] 1 illustrates a specific embodiment of a method for providing a spice rope having a first rope and a second rope of 12 strands. [Figure 5A]1 illustrates a specific embodiment of a method for providing a spice rope having a first rope and a second rope of 12 strands. [Figure 5B] 1 illustrates a specific embodiment of a method for providing a spice rope having a first rope and a second rope of 12 strands. [Figure 5C] 1 illustrates a specific embodiment of a method for providing a spice rope having a first rope and a second rope of 12 strands. [Figure 6A] 1 illustrates a specific embodiment of a method for providing a spice rope having a first rope and a second rope of 12 strands. [Figure 6B] 1 illustrates a specific embodiment of a method for providing a spice rope having a first rope and a second rope of 12 strands. [Figure 6C] 1 illustrates a specific embodiment of a method for providing a spice rope having a first rope and a second rope of 12 strands. [Figure 7] 1 shows a plot of displacement versus rotation cycle. [Figure 8] 1 shows a rope being prepared for splicing in step i of the procedure disclosed herein. DETAILED DESCRIPTION OF THE INVENTION

[0046] FIG. 1A shows step ii, which involves unbraiding the rope tail to the center of the splice, as determined in step i (not shown).

[0047] FIG. 1B shows the joining of strands by alternately placing four left-handed twisted strands in opposite directions (solid lines), then doing the same for four adjacent right-handed twisted strands (dotted lines), and continuing this until all (24) strands are identically placed.

[0048] 2A shows the optional further step of marking the first rope at locations BB and AA and marking the second rope at locations A and B. The first and second helical sections extend from the splice center to locations A and AA, respectively, and each have a length of 40 times the diameter of the first rope (equal to the diameter of the second rope in this case). The first and second tapered sections extend from locations A and AA to locations B and BB, respectively, and each have a length of at least 10 times the diameter of the first rope (equal to the diameter of the second rope).

[0049] FIG. 2B shows yet another preparatory step: labeling the individual strands. The left-handed and right-handed strands of the second rope are labeled LHS#-A and RHS#-A, respectively, while the left-handed and right-handed strands of the first rope are labeled LHS#-B and RHS#-B, respectively. These optional steps shown in FIGS. 2A and 2B are included in this description for clarity. However, in practice, these preparatory steps may be skipped by experienced splicers.

[0050] FIG. 3A shows an optional step (steps iv-b) of twisting two adjacent strands of the second rope together in the same twist direction as the orientation of the individual strands (similar to Lang twisting).

[0051] FIG. 3B shows an optional step (steps iv-b) of twisting two adjacent strands of the second rope together in the same twist direction as the orientation of the individual strands (similar to Lang twisting).

[0052] FIG. 3C shows an optional step (steps iv-b) of twisting two adjacent strands of the second rope together in the same twist direction as the orientation of the individual strands (similar to Lang twisting).

[0053] FIG. 4A shows the construction of the second helical section in step iv, which comprises inserting bundled and optionally twisted strands of the second rope into the first rope in a helical pattern.

[0054] FIG. 4B shows the construction of the second helical section in step iv, which comprises inserting bundled and optionally twisted strands of the second rope into the first rope in a helical pattern.

[0055] FIG. 4C shows the construction of the second helical section in step iv, which comprises inserting bundled and optionally twisted strands of the second rope into the first rope in a helical pattern.

[0056] As shown in Figure 4A, the set of bundled and twisted strands labeled RHS1 / 2-A follows the nearest strand of the first rope until the set is inserted into a left-handed spiral pattern (following a two-over and two-under pattern) in the construction of the first rope until location AA is reached. Thus, as shown, inserting comprises inserting a strand of the second rope at least 10 times, preferably at least 15 times, over two or more strands and under two or more strands of the first rope, each with a twist direction opposite to that of the inserted strand, in a spiral pattern that each follows the nearest strand of the second rope. Similarly, as shown in Figure 4B, the set of bundled and twisted strands labeled LHS1 / 2-A follows the nearest strand of the first rope until it reaches site AA, where the set is inserted into a left-handed helical pattern (following a two-over and two-under pattern) in the construction of the first rope. This should continue for the other strands as well (Figure 4C).

[0057] FIG. 5A shows the construction of the second tapered section in step vi, which comprises providing the second tapered section by inserting one or more strands of the second rope into the first rope in a spiral pattern, and cutting away a portion of the strand volume during said inserting.

[0058] FIG. 5B shows the construction of the second tapered section in step vi, which comprises providing the second tapered section by inserting one or more strands of the second rope into the first rope in a spiral pattern, and cutting away a portion of the strand volume during said inserting.

[0059] FIG. 5C illustrates the construction of the second tapered section in step vi, which comprises providing the second tapered section by inserting one or more strands of the second rope into the first rope in a spiral pattern, and cutting away a portion of the strand volume during said inserting.

[0060] As shown in Figure 5A, approximately one-third of the original total strand volume of the set of bundled and twisted strands labeled RHS1 / 2-A is cut off, and this set is further inserted into the first rope structure following the same spiral pattern as in step iv, as shown in Figure 4A. As mark BB is approached, approximately one-third of the original strand volume is again cut off until another tuck can be made, creating the final tuck. Figure 5B shows a similar procedure for the set of bundled and twisted strands labeled RHS1 / 2-A. This should be continued for the other strands in the same manner (Figure 5C).

[0061] The above steps iv and vi should be repeated for the strands of the first rope LHS-1B to LHS-6B and RHS-1B to RHS-6B.

[0062] FIG. 6A shows the resulting splice before the remaining splice ends are cut off.

[0063] FIG. 6B shows the resulting splice before the remaining splice ends are cut off.

[0064] Figure 6C shows the resulting splice before the remaining splice ends are cut. After the splice is embedded, the remaining splice end tail can be cut along the rope body. Figure 6A shows the entire splice diagrammatically, as also shown in photographic Figure 6B. Figure 6C shows a portion of the helical section diagrammatically.

[0065] FIG. 7 shows a plot of displacement versus rotation cycle.

[0066] FIG. 8 shows the rope being prepared for splicing in step i of the procedure disclosed herein.

[0067] The spliced ​​ropes of the present invention are particularly suitable for CBOS applications such as hoisting and lifting under various conditions. For example, they are suitable for lifting loads over long distances of hundreds of meters to kilometers, or for marine and offshore applications such as deep-sea mooring and deep-sea lifting. A particular embodiment of the present invention is therefore the use of the spliced ​​ropes of the present invention for these applications. An embodiment is a method comprising using the spliced ​​ropes of the present invention in CBOS applications. Another embodiment is a method comprising lifting and / or mooring a cargo and / or vessel with the spliced ​​ropes of the present invention, preferably deep-sea mooring and / or deep-sea lifting.

[0068] As used herein, the singular forms "a," "an," and "the" are intended to include the plural forms as well, unless the context clearly dictates otherwise. The term "and / or" includes any and all combinations of one or more of the associated listed items. It will be understood that the terms "comprises" and / or "comprising" specify the presence of stated features but do not exclude the presence or addition of one or more other features.

[0069] Although for clarity and conciseness of description, features are described herein as part of the same or separate embodiments, it will be understood that the scope of the invention may include embodiments having all or any combination of the described features.

[0070] The invention can be illustrated by the following non-limiting examples.

[0071] [Example 1] A braided rope made from Avient's Dyneema DM20 XBO, a high-performance fiber with a nominal diameter of 28 mm, a specified MBF of 545 kN, and a 12x3 construction, was spliced ​​using the present invention. Specifically, the tails were unwound to a strand level of 75 times the rope diameter (abbreviated as "xd"). The strands were then bundled and twisted together in pairs, and the resulting set of strands was inserted in a helical pattern (in both directions) over a length of 40xd. One-third of the fiber volume was then tapered in two steps, and inserted in a helical pattern (in both directions) over a length of 20xd. The total spliced ​​length was approximately 120xd.

[0072] Figures 6B and 6C show the resulting splice in its entirety and a portion of its helical section, respectively.

[0073] Three tensile test samples were produced from this rope with a splice according to the invention located in the center of the tensile test sample. The tensile tests showed an average breaking force of 571 kN, or an efficiency of over 100%.

[0074] [Example 2] The splicing procedure described in WO 2013 / 134033 was used to splice the braided rope described in Example 1. The rope was spliced ​​as follows with reference to EP 2822887 (one end is described, but both ends are similarly spliced): · Separation of rope end strands into six rope sets of two strands (Figure 5, page 18); · For a minimum of six strands, one end is embedded in the core of the other end (Figure 6, p. 19); · All six strand sets are inserted 1x under the two construction strands (Figure 7, page 20); · Three sets of strands are inserted twice between each other longitudinally under one construction strand (Fig. 8, p. 21); · The other three sets of strands are inserted three times in a helical direction (Fig. 10, p. 23); · The previous helical splice strand is inserted longitudinally here twice, 1 above and 1 below (Fig. 11, p. 24); · The previous longitudinal splice strand is now inserted helically for three tucks (Fig. 14, p. 27); · Here, every strand is inserted four times, one above and one below (Fig. 16, p. 29); · Finally, the strand ends are embedded into the core of the structure.

[0075] The resulting spliced ​​rope, as well as the rope obtained in Example 1, were tested in a CBOS testing machine at a load of 180 kN or 33% of the MBF, with a sheave rotation speed of 1 meter / second and a sheave diameter of 800 mm. A plot of displacement versus rotation cycles is included in Figure 7. The rope spliced ​​according to the procedure disclosed in WO 2013 / 134033, identified as Splice A, exhibits a much higher displacement rate, taken as the slope of the displacement curve in the steady-state regime. The displacement rate of Splice A is more than 10 times that of Example 1, identified as Splice B. The plot also shows that the time to failure of Splice B is significantly higher than that of Splice A. This indicates a significant improvement in the stability of the splices obtained with the present invention relative to the state of the art.

[0076] [Example 3] A braided rope made from Avient's Dyneema DM20 XBO high-performance fiber, with a nominal diameter of 68 mm, an MBF of 2912 kN, and a 12x3 construction, was spliced ​​using the splicing procedure described in this invention with another braided rope made from Avient's Dyneema DM20 XBO high-performance fiber, with a nominal diameter of 88 mm, an MBF of 4590 kN, and a 12x3 construction. Figure 8 shows the ropes being prepared for splicing in step i of the procedure disclosed herein. The spliced ​​ropes were tested using the standardized splice integrity test according to DNV-RP-E305, applied at a higher load level of 1456 kN, which is 50% of the MBF of the weaker rope. The splice held firm for tests performed for over 24,000 cycles, indicating excellent splice stability under these demanding test conditions. After the cyclic test, a residual strength test was performed to confirm the efficiency of the splice and showed a breaking load of 3630 kN for the spliced ​​rope.

Claims

1. A spliced ​​synthetic rope, A first rope having a first set of strands, A second rope having a second set of strands, and A splice for connecting the first rope and the second rope, comprising a splice having a splice center, The splice comprises at least a helical section having a first helical section and a second helical section, and two tapered sections located on each side of the helical section and at each end of the splice. The first helical section comprises one or more strands of the first rope inserted into the helical pattern of the second rope, and the second helical section comprises one or more strands of the second rope inserted into the helical pattern of the first rope, The tapered section comprises a first tapered section and a second tapered section, each having one or more strands of the first rope and the second rope, which are inserted into the second rope and the first rope in a helical pattern, wherein the strands are a spliced ​​composite rope whose volume decreases in the direction away from the splice center.

2. The spliced ​​rope according to claim 1, wherein the strands inserted into the spiral pattern are bundled together with sets of two or more adjacent strands.

3. The spliced ​​rope according to any one of claims 1 to 2, wherein the strands inserted in a spiral pattern are bundled and twisted together in sets of two or more adjacent strands, preferably twisted together in the same twisting direction as the orientation of the individual strands.

4. The spliced ​​rope according to any one of claims 1 to 2, wherein one or more strands of the first rope inserted into the first helical section in a helical pattern are provided with at least 10, preferably at least 15, helical tucks above and below the strands of the second rope, and / or the one or more strands of the second rope inserted into the second helical section in a helical pattern are provided with at least 10, preferably at least 15, helical tucks above and below the strands of the first rope.

5. The spliced ​​rope according to any one of claims 1 to 2, wherein one or more strands of the first rope inserted into the first tapered section in a spiral pattern are provided with at least five, preferably at least seven, spiral tucks above and below the strands of the second rope, and / or the one or more strands of the second rope inserted into the second tapered section in a spiral pattern are provided with at least five, preferably at least seven, spiral tucks above and below the strands of the first rope.

6. The spliced ​​rope according to any one of claims 1 to 2, wherein the spiral pattern into which one or more strands of the first rope and the second rope are inserted into the spiral section and / or the tapered section has the orientation opposite to the orientation of the yarn on which each of the strands is based, and optionally opposite to the orientation of the twist of two or more adjacent sets of strands twisted according to claim 3.

7. A spliced ​​rope according to any one of claims 1 to 2, wherein one or more strands of the first rope and the second rope are inserted into the helical section and / or the tapered section of the second rope and the first rope, respectively, and each is preferably positioned adjacent to each adjacent strand of the second rope and the first rope, so as to follow the original structural pattern of the second rope and the first rope, respectively.

8. The spliced ​​rope according to any one of claims 1 to 2, wherein the strands of the first rope and / or the second rope inserted into the first tapered section and / or the second tapered section have a strand volume that decreases in stages by at least 1 / 25, preferably at least 1 / 10, more preferably at least 1 / 5, and most preferably at least 1 / 3 of the original volume of the strand.

9. The spliced ​​rope according to any one of claims 1 to 2, wherein the splice has a total length of less than 240 times, preferably less than 180 times, more preferably less than 150 times, and most preferably less than about 125 times, the diameter of the first rope and / or the second rope.

10. The spliced ​​rope according to any one of claims 1 to 2, wherein the first helical section and / or the second helical section each independently have a total splice length of less than 80 times, preferably less than 60 times, and more preferably less than 55 times, the diameter of the first rope and / or the second rope.

11. The spliced ​​rope according to any one of claims 1 to 2, wherein the first tapered section and / or the second tapered section each independently have a splice length of less than 40 times, preferably less than 30 times, more preferably less than 25 times, and most preferably about 10 to 20 times, the diameter of the first rope and / or the second rope.

12. The spliced ​​rope according to any one of claims 1 to 2, wherein the first rope and the second rope independently comprise 4 to 24 strands, preferably 12 strands.

13. The spliced ​​rope according to any one of claims 1 to 2, wherein the first rope and the second rope have the same rope diameter or different rope diameters.

14. The spliced ​​rope according to any one of claims 1 to 2, wherein the first rope and the second rope have different individual numbers of strands.

15. A method for providing a spliced ​​synthetic rope according to claims 1 to 2, wherein the method is i. The steps of aligning the first rope and the second rope and determining the splice center, ii. A step of unraveling the tails of the first rope and the second rope up to the center of the splice, iii. The step of providing the first spiral section by inserting one or more stands of the first rope into the second rope in a spiral pattern, iv. Providing the second spiral section by inserting one or more stands of the second rope into the first rope in a spiral pattern, v. Providing the first tapered section by inserting one or more stands of the first rope into the second rope in a spiral pattern, and by cutting off a portion of the volume of the strand during the insertion; vi. A method comprising the step of providing the second tapered section by inserting one or more stands of the second rope into the first rope in a spiral pattern, and cutting off a portion of the volume of the strand while inserting them.

16. The method according to claim 15, wherein the first rope and the second rope have different rope diameters, and step ii comprises adjusting the volume of the thickest rope to preferably match the strength of the other rope, preferably by tapering the rope, and / or step ii comprises unraveling the tails of the first rope and the second rope until the splice center is at the level of the yarn or sub-strand.

17. Step III iiia. The step of bundling two or more adjacent strands of the first rope, optionally twisting them together, preferably in the same twisting direction as the orientation of the individual strands, iiib. The method according to claim 15, comprising the step of inserting the bundled, optionally twisted strands into the second rope in a spiral pattern.

18. Step IV is iva. The step of bundling two or more adjacent strands of the second rope, optionally twisting them together, preferably in the same twisting direction as the orientation of the individual strands, ivb. The method according to claim 15, comprising the step of inserting the bundled, optionally twisted strands into the first rope in a spiral pattern.

19. The method according to claim 15, wherein the insertion in step iii and / or iv is to insert the strands of the first rope and / or the second rope at least 10 times, preferably at least 15 times, in a spiral pattern, above and below the strands of the second rope and / or the first rope, respectively, along the nearest strand of the second rope and / or the first rope, preferably in a spiral pattern having the twist direction opposite to the twist direction of the inserted strand.

20. The method according to claim 15, wherein the insertion in step v and / or vi is to insert the strands of the first rope and / or the second rope at least five times, preferably at least seven times, in a spiral pattern along the nearest strand of the second rope and / or the first rope, preferably in a spiral pattern having the twist direction opposite to the twist direction of the inserted strand, and more preferably in a spiral pattern that is the same as the spiral pattern in step iii and / or iv.

21. The method according to claim 15, wherein the insertion and cutting in step v and / or step vi comprises one or more additional steps of cutting off at least 1 / 25 of the volume of the original strand at the beginning of the first tapered section and / or the second tapered section, inserting the remaining strand into the second rope and / or the first rope, respectively, then cutting off at least 1 / 25 of the volume of the original strand before another insertion of the remaining strand can be made, inserting the remaining strand into the second rope and / or the first rope, respectively, and optionally cutting off the remaining strand end along the rope body.

22. Use of a spliced ​​rope according to any one of claims 1 to 2 in CBOS applications.

23. The use of the spliced ​​rope according to claim 22, wherein the CBOS application includes deep-sea mooring, deep-sea lifting, etc.

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