HOISTING ROPE

Abstract

The invention is directed to a synthetic hoisting rope comprising a solid core surrounded by a first braided layer of a first set of strands that is surrounded by a second braided layer of a second set of strands.

Claims

1. Synthetic hoisting rope comprising a solid core surrounded by a first braided load-bearing layer of a first set of strands that is surrounded by a second braided load-bearing layer of a second set of strands, wherein the first set and/or second set of strands comprise high performance fibers having a tenacity of at least 15 g/den, and wherein the second braided load-bearing layer has a load-bearing capacity of at least 60% of a total load-bearing capacity of the rope, wherein the load-bearing capacity of each load-bearing layer is determined according ISO 2307, and wherein a cross-sectional area of the solid core is less than 3%.

2. The synthetic hoisting rope according to claim 1, wherein the high performance fibers have a tenacity of at least 20 g/den.

3. The synthetic hoisting rope according to claim 1, further comprising at least one additional braided layer of an additional set of strands that surrounds the second braided layer.

4. The synthetic hoisting rope according to claim 1, wherein the sets of strands independently comprise 3 to 32, preferably 6 to 24, and more preferably 12 strands.

5. The synthetic hoisting rope according to claim 1, wherein the braided layers are independently constructed by braiding a sub-set of twisted strands.

6. The synthetic hoisting rope according to claim 1, wherein the solid core comprises one or more monofilaments comprising a thermoplastic resin such as polyethylene, polypropylene, polyamide, polyester, thermoplastic polyurethane, polytetrafluoroethylene, other fluoropolymer or combinations thereof.

7. The synthetic hoisting rope according to claim 1, wherein the braided layers independently comprise yarns that comprise a protective coating, preferably a protective coating comprising polyurethane, silicon or a combination thereof.

8. The synthetic hoisting rope according to claim 7, wherein the coating surrounds the yarns and preferably the coating surrounds individual fibers that form those yarns.

9. The synthetic hoisting rope according to claim 1, wherein the second braided load-bearing layer has a load-bearing capacity of at least 65%, more preferably at least 70% of the total load-bearing capacity of the rope.

10. The synthetic hoisting rope according to claim 1, having a diameter between 0.5 to 10 cm, preferably between 1 to 5, more preferably between 2 to 4 cm.

11. The synthetic hoisting rope according to claim 1, wherein the cross-sectional area of the solid core is less than 2%, more preferably between 1 and 2% based on a cross-sectional area of the synthetic hoisting rope.

12. The synthetic hoisting rope according to claim 1, having a minimum breaking force of at least 10, preferably at least 20, more preferably at least 30 metric ton-force.

13. The synthetic hoisting rope according to claim 1, wherein the solid core is a functional solid core, preferably comprising a non-destructive testing functionality.

14. The synthetic hoisting rope according to claim 1, further comprising one or more successive braided layers that surrounds the second braided load-bearing layer.

15. A drum or crane comprising the synthetic hoisting rope according to claim 1.

16. Use of a hoisting rope according to claim 1, preferably for hoisting load by a crane.

Description

EXAMPLE 1

[0036] A hoisting rope having a diameter of 20.0 mm, consisting of a solid core of a monofilament comprising polyethylene (Tiptolene Thick Mono commercially available from Lankhorst Yarns), a first 12-strand plaited layer of Dyneema fibers and a second 12-strand plaited layer of Dyneema fibers, wherein the fibers are coated with synthetic polymers based on anionic polyurethane.

[0037] The rope was testing in a CBOS test with the test conditions as provided in table 1.

TABLE-US-00001 TABLE 1 CBOS test conditions Test conditions: Sheave diameter: 400 bottom-bottom [mm] Groove material: RVS 304 [] Groove diameter: 1.06 [x rope diameter] Groove angle: 30 [] Cyclic frequency 3.75 [mcycles/min] Single bend zone (max): 29.9 [x rope diameter] Double bend zone: 20 [x rope diameter]

[0038] The bending fatigue properties of the rope are provided in FIGS. 7 and 8, wherein the rope is labeled with LankoLift S 20 mm. FIG. 7 also shows comparative results of SWRs as determined by O. Vennemann et al., AcergyOTC 2008. The rope of the present example shows excellent bending fatigue properties. FIG. 8 shows the temperature profiles of two samples (1 and 2) of the rope over time during the CBOS test.

Example 2

[0039] Hoisting ropes according to the rope in example 1 were prepared, having different diameters and properties as provided in table 2.

TABLE-US-00002 TABLE 2 MBL* MBF** Rope diameter Weight (spliced) (spliced) [mm] [kg/m] [mTon] [kN] 16 0.175 21.26 208.49 18 0.224 28.32 277.72 20 0.269 37.54 368.14 24 0.403 47.5 465.82 26 0.468 54.65 535.93 28 0.535 63.37 621.45 32 0.667 77.04 755.5 36 0.831 91.32 895.54 38 0.899 98.45 965.46 40 0.971 105.21 1031.76 *MBL stands for the minimum breaking load in metric ton; one metric ton equals 1000 kg. **MBF stands for the minimum breaking force as determined by ISO/DIS 2307.