JP2916520B2 - Fatigue resistant wire lobe - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fatigue-resistant wire rope suitable for use as a moving rope for a cargo handling machine such as a crane or a hoist, a construction machine, an elevator, and a support rope. is there.

[0002]

2. Description of the Related Art A wire rope (JIS standard G3525) shown in FIG.
To be more specific, a Warrington seal-type multilayer formed by twisting six strands 11b, twelve strands 11c, d, and twelve strands 11e around a strand (core wire) 11a. IWRC6 × WS having twisted strands 11 and configured by twisting six strands 11 around a wire rope core (IWRC) 12 having a 7 × 7 structure
It has the rope structure of (31), and its strand 1
A very small space between the wires is formed between the wires of each layer of the first layer, and the strand twist length L0 is configured to be 7.5 to 8.5 times the strand diameter D0.

[0003]

The conventional cable ropes of the above-mentioned type generally have ropes having the above-mentioned structure. However, the use load increases due to the recent increase in size and performance of equipment. The diameter of the wire rope or sheave is reduced, and the fluctuation range of the tension and bending load applied to the wire rope is increased, resulting in early fatigue disconnection, reduction in the diameter of the winding drum and increase in the number of winding layers For example, the wire ropes are rubbed against each other to cause shape collapse, disconnection, and the like. Therefore, improvement in bending fatigue resistance, tensile fatigue resistance, shape collapse resistance, and the like have been issues.

The present invention has been developed to address the above-mentioned problems, and its object is to improve bending fatigue resistance, tensile fatigue resistance, shape collapse resistance, and the like. Another object of the present invention is to provide a fatigue-resistant wire rope having improved durability.

[0005]

According to the present invention, there is provided a wire rope formed by twisting a plurality of multi-layered strands, wherein the strands are arranged such that 2 <strand gap / strand diameter × A space between the strands of 100 <4 is formed, and the strand twist length is 5
Up to 6 times, and 19 to 41 strands are twisted in parallel, thereby effectively improving the fatigue resistance and the shape collapse resistance and the like.

[0006]

In a wire rope formed by twisting a plurality of multi-layered strands, the strands are appropriately reduced in strand twist length to 5 to 6 times the strand diameter to form 19 to 41 strands. Twisted in a parallel twist, it is relatively tight and hardly collapses even under strong pressure, stress is distributed uniformly and it is formed into a structure that is basically flexible and fatigue-resistant, and its strands A space between wires of 2 <wire gap / wire diameter × 100 <4 is formed between the wires of each layer, effectively reducing internal wear and fatigue disconnection due to secondary bending, and overall excellent. Bending fatigue resistance, tensile fatigue resistance, and shape collapse resistance.

[0007]

1 (A) and 1 (B) show an embodiment of a strand of the present invention.
It is configured as a fatigue-resistant wire rope having the structure shown in FIG. In the figure, 1 is a strand, 1a, 1b, 1c, 1d, 1
e is a strand constituting the strand 1, da, db, dc,
dd and de are the diameters of the respective wires (diameters of the wires 1a to 1e), and S is the wires 1b, 1c and 1 of each layer of the strand 1.
A space between wires formed by providing a wire gap between d and 1e, D is a strand diameter (outer diameter of the strand 1), L is a strand twist length (one twist pitch of the strand 1), As shown in FIG. 1, 1 + 6 + (6 + 6) formed by twisting six wires 1b, twelve wires 1c and 1d, and twelve wires 1e around the wire 1a.
2, a six-strand 1 is twisted around a wire rope core (IWRC) 12 having a 7 × 7 structure as shown in FIG.
In the wire rope configured in the WS (31) structure, the strand 1 includes the strands 1b, 1c and 1d, and 1e of each layer.
A space S between the wires of 2 <wire gap / wire diameter × 100 <4 is formed between them, and the strand twist length L is made 5 to 6 times the strand diameter D to obtain 19 to 41.
The present invention provides a fatigue-resistant wire rope in which the strands 1a to 1e are twisted in parallel.

In the outermost layer, as shown in FIG. 1 (A), the inter-element space S formed in the strand 1 is such that the element gap and the element diameter de of each element 1e are 2 <element. The gap / element diameter de × 100 <4 is formed, and in the next layer, the elements 1c and 1d
In the innermost layer, substantially the same inter-element space S is formed between the elements in the next layer and the innermost layer based on the average diameter of the element diameters dc and dd in the innermost layer based on the element diameter db of the element 1b. . further,
In the fatigue-resistant wire rope, the rope twist length is appropriately set to be longer in accordance with the setting (shortening) of the strand twist length L of the strand 1 as described above.
It is constructed by twisting in a normal twist to improve the quality and reliability of the rope, and the rotation force of the rope is adjusted to produce a non-rotating wire rope having a small torque coefficient.

In the fatigue wire rope of the present invention, as described above, each strand 1 is formed between the wires of each layer with a space S between wires of 2 <wire gap / wire diameter × 100 <4. In addition, the strand twist length L is 5 to 6 times the strand diameter D, and 19 to 41 strands 1a to 1e are twisted in parallel twist.
The strand twist length L is appropriately shortened as described above to make the strands parallel, so that the strands of the strands 1 are densified, so that the strands do not easily collapse even under strong pressure, and the stress is uniformly distributed. Basically, it is formed to have a structure having a high flexibility and fatigue resistance, and due to the appropriate inter-wire space S formed between the wires of each layer of the strand, fatigue due to internal wear and secondary bending is caused. Disconnection is effectively reduced, and the bending fatigue resistance, tensile fatigue resistance, and shape collapse resistance are significantly improved, and the durability is greatly increased.

As shown in Table 1, IWRC 6 × Ws (3
1) Conventional example 1 of structure, IWRC formed in different rope structures by changing strand twist length L and inter-wire space S
6 × Ws (31), IWRC 6 × Fi (29), I
WRC 6 × Ws (36) and IWRC 6 × Ws
(31) Examples 1 to 4 of the structure, and further, IWRC 6 ×
Each of the wire ropes of Comparative Examples 1 to 3 having a Ws (31) structure was manufactured as a sample, and subjected to a bending fatigue test, a tensile fatigue test, and a shape loss test, and the results shown in Table 2 were obtained. In the bending fatigue test, as shown in FIG. 3A, a sample a was hung in an S-shape on two test sheaves c and connected to an auxiliary rope b, and a load of 1/6 of a specified breaking load was applied by a hydraulic ram d. F was loaded and repeated forward and backward movements by the drive drum e, and the relationship between the number of passes through the test sheave portion and the number of broken wires was examined. The tensile fatigue resistance was as shown in FIG. 3 (B). One end of each sample (wire rope) a was inclined at 5 °, a tension of 2 to 7 tf was applied to the sample a at 2 million times at a frequency of 2 Hz, and the disconnection state at that time was inspected. In the test, three samples (wire ropes) a were put in the grooves of the sheave g as shown in FIG. This is a test of the disconnection situation.

In a test comparison between Conventional Example 1 and Example 1,
In the bending fatigue resistance, the number of repetition cycles until the occurrence of the first disconnection was 1.7 thousand in the first embodiment, compared with 13,000 in the first conventional example.
The number of repetition cycles up to 5% disconnection (9 strands) in the twist length (1 twist pitch) of the sample (wire rope) is 27% more than in the conventional example 1 In Example 1, it was 36,000 times, and the bending fatigue resistance was greatly improved. In addition, the conventional example 1 has a tensile fatigue property of 15%.
Although the rope was broken at 100,000 times and 2 million times, in Example 1, even after 2 million times, the wire was only broken. Further, in the case of the shape collapse property, in Conventional Example 1, disconnection occurred frequently from 50 times, whereas in Example 1, only several disconnections occurred in 200 times. In addition, almost the same results were confirmed for Examples 2, 3, and 4.

[0012]

[Table 1]

Examples 1 to 4 and Comparative Example 1 shown in Table 2
As is apparent from the results of the comparative tests of Nos. 1 to 3, comprehensively, in the strands of the parallel twist, the space S between the wires of each layer is formed as 2 <wire gap / wire diameter × 100 <4. And the strand length L is changed to the strand diameter D.
It has been confirmed that by setting the ratio to 5 to 6 times, excellent characteristics with respect to bending fatigue resistance, tensile fatigue resistance and shape collapse resistance can be obtained.

The fatigue-resistant wire rope of the present invention can be applied not only to the illustrated examples and display examples but also to strands formed by parallel-twisting 19 to 41 strands, and further to strands containing strand fibers. , Its strand 6
The present invention can be applied to a wire rope in which two or eight wires are twisted, and the same operation and effect can be obtained.

[0015]

[Table 2]

[0016]

The present invention has the above-described configuration,
In a wire rope configured by twisting a plurality of multilayer twisted strands, the strands form a space between wires of 2 <wire gap / wire diameter × 100 <4 between wires of each layer, By making the strand twist length 5 to 6 times the strand diameter and twisting it into parallel twists with 19 to 41 strands, bending fatigue resistance, tensile fatigue resistance, shape collapse resistance, etc. It is significantly improved and the durability is greatly increased.

[Brief description of the drawings]

FIG. 1 is a cross sectional view (A) and a side view (B) showing one embodiment of a strand of the present invention.

FIG. 2 is a cross-sectional view (A) and a side view (B) showing a conventional example of a wire rope.

FIG. 3 is a side view mechanism diagram (A) to (C) showing each test mechanism of the wire rope.

[Explanation of symbols]

1a, b, c, d, e strand 1 strand d-da, db, dc, dd, de strand diameter S inter-strand space D strand diameter L strand twist length

Claims (1)

(57) [Claims] 1. In a wire rope configured by twisting a plurality of multi-layered strands, the strands are arranged such that 2 <wire gap / wire diameter × 100 <
In addition to forming a space between the strands of No. 4 and making the strand twist length 5 to 6 times the strand diameter,
A fatigue-resistant wire rope, wherein one strand is twisted in a parallel twist.