KR100318185B1 - Wire rope for controlling a machine having high fatigue-resistant characteristics - Google Patents

Abstract

The present invention relates to improvement of fatigue resistance of wire rope for device operation used for operation of various devices.

In the present invention, the inner strand (d2) of 6 strands is twisted around the center strand (d1) to form the lower strand (l), and the outer strand (d3) of 12 strands is twisted around the lower strand to form the upper strand (u). In the strand of 1x19 structure, the entrance angles of the upper edge (u) and the lower edge (l) are the same, and the upper and lower edge pitch ratios are 45 to 55%, wherein the ratio of the center element wire to the inner layer wire (d1 / d2) Is 1.13 to 1.17, the ratio of the ratio of the inner layer wires to the outer layer wires (d2 / d3) is 0.90 to 0.98, and the inter-wire spacing of the inner wires is 4 to 6%.

Since the strands according to the present invention have the same entrance angles between the upper and lower edges, uniform load distribution is achieved by the element wires constituting the upper edge and the element wire constituting the lower edge during the action of the tensile load, so that the load is concentrated on a specific element wire. Therefore, the cutting load is prevented from falling, which improves the cutting force and fatigue resistance and ultimately prolongs the life of the strand, which is useful not only as the strand itself but also as the required strand constituting the wire rope of the multi-layered structure. Could be utilized.

Description

Wire rope for controlling a machine having high fatigue-resistant characteristics}

The present invention relates to the improvement of fatigue resistance of wire ropes used for the operation of various devices, and more particularly in the strands of the multi-layered strand structure consisting of upper and lower edges so that the entrance angles of the upper and lower edges are kept the same. The present invention relates to a device-operated wire rope having excellent fatigue resistance to improve fatigue resistance and cutting force by distributing load evenly to each element of the upper and lower edges when the load is applied.

In general, wire ropes used for the operation of various machines or equipment are repeatedly moved in contact with the sheaves or rollers under a (tension) load. It depends on characteristics such as performance and cutting force and wear resistance.

1 is a cross-sectional view of a strand of a 1x19 structure, which is a typical form of the strand constituting the operation wire rope based on the structure and characteristics of the conventional operation wire rope as follows.

As shown in the drawing, the conventional strand S has six inner layer wires d2 twisted outward from the center element wire d1 to form a lower lead 1, and 12 outer layer wires d3 are formed on the outer circumferential surface of the lower lead. The upper edge (u) consisting of a twisted structure.

The conventional strand (S) is the outer layer element wire on the outer peripheral surface of the lower edge after completing the process of forming the lower lead (l) to the inner layer wire (d2) is twisted while winding spirally with a constant penetration angle on the center element wire (d1) (d3) is manufactured through a two-step twisted pair process in which the upper edge (u) is formed by being twisted while maintaining a constant entrance angle.

By the way, the conventional strand (S) has a entering angle between the inner layer wire (d2) constituting the lower edge (l) and the outer layer wire (d3) constituting the upper edge (u) (detailed description of the angle of inclination will be described later) As a result, there is a difference in the required lengths of the inner layer wire d2 and the outer layer wire d3 per unit length of the strand.

Thus, in strands having different entrance angles between the upper edge (l) and the lower edge (u), when the tensile load is applied, each element wire of the upper and lower edges (d2) ( There is a difference in the load on d3).

In other words, the load applied to the strands is not evenly distributed and acts on each strand constituting the strand. Or deformed and ultimately degrades the fatigue resistance and cutting force of the strand.

As a result of investigating the entrance angles between the upper and lower edges by collecting various wire ropes used in the industry including the operation of the equipment currently on the market, all wire rope products showed different entrance angles between the upper and lower edges. Yes, it was observed, and accordingly it seems to have the above problem as it is.

According to the present invention, when the tensile load acts on the strands by making the entrance angles of the inner layer wire and outer layer wire forming the upper and lower edges of the conventional device operating wire rope or the strands constituting the same coincide with each other, the loads constitute the upper and lower edges of the strand. It is an object of the present invention to provide a machine-operated wire rope to improve the fatigue resistance and cutting properties of the wire rope by being distributed evenly distributed to all the element wires.

Another object of the present invention is to maintain the pitch ratio of the upper and lower edges within a certain range so that the entrance angles of the upper and lower edges constituting the strands coincide with each other, and the diameter ratio between the element wires constituting each layer is within a specific range. It is to provide a device operating wire rope with excellent fatigue resistance by being managed.

1 is a cross sectional view of a strand of a 1x19 structure;

Figure 2 is a partially cutaway perspective view showing an embodiment strand structure of the present invention.

Figure 3 (a), (b) is for explaining the engagement rate of the strands,

(A) shows the strand pitch (L),

(B) shows layer depth Dp.

4 is a cross-sectional view of an 8x7 + 1x19 wire rope in which the strand according to the present invention is used as a rope core.

((Description of the code for the main part of the drawing))

d1. Center element d2. Inner wire

d3. Outer layer wire l. Ha Yeon

u. Stage

In the above object of the present invention, in the strand of 1x19 structure in which the lower edge of six strands of inner strands is formed outside the center element strand, and the upper strand of 12 strands of outer strand strands is formed thereon, the entrance angle of the upper strand and the lower strand It is achieved by the structure which is mutually the same, and the pitch ratio of upper and lower edges is 45 to 55%.

Since the strands of the present invention have the same entrance angle of the upper and lower edges, the tensile load acting on the strands is uniformly distributed to the inner wires and the outer wires of the upper and lower edges so as to improve cutting force and fatigue resistance. do.

On the other hand, in the present invention, the pitch ratio of the upper edge to the lower edge of the strand is limited to 45 to 55%, because if the pitch ratio is less than 45%, the bending height of the inner layer wire is lower than that of the outer layer wire, First of all, when the tensile stress or the like is broken, the cutting load is decreased. On the contrary, when the pitch ratio exceeds 55%, the opposite of the above case occurs, the cutting load and durability are also lowered. It is preferable to make it into the range of 45 to 55%.

In the present invention, in managing the design point of the strand, the diameter ratio of the center element wire to the inner layer element wire is in the range of 1.13 to 1.17, and the diameter ratio of the inner layer wire to the outer layer element wire is in the range of 0.90 to 0.98, Another technical feature is that the spacing between inner layer wires is 4 to 6%.

The strand wire diameter management range of the strand according to the present invention and the spacing range of the inner layer wires are controlled so that a small compressive stress acts on the inner layer wires constituting the lower smoke by managing the spacing of the lower edge and managing the spacing of the lower edge, and the upper edge. The outer layer wires forming a close contact with each other are arranged so that the left and right movements are suppressed, thereby reducing the compressive stress on the inner layer wires subjected to the high compressive stress, and consequently, improve the fatigue resistance of the strands.

In other words, the inner layer wire existing between the center element wire and the outer layer element wire in the 1x19 structure has a structural characteristic that a relatively large amount of compressive stress is applied, so that the inner layer where the compressive stress is concentrated in the conventional strand It was a general tendency that deformation, damage, or cutting occurred in the element wire first to reduce the fatigue resistance of the strand itself. However, in the present invention, the compressive stress concentrated in the inner layer wire is distributed by controlling the element diameter and managing the spacing. The fatigue resistance of strands is improved by the fatigue resistance of the inner layer wire.

Specific matters related to the above objects and technical configurations of the present invention and the effects and the like will be clearly understood by the following detailed description with reference to the drawings showing preferred embodiments of the present invention.

First, the basic cross-sectional structure of the strand of 1x19 structure according to the present invention is the same as the structure shown in FIG.

Next, Figure 2 is a partially cutaway perspective view of the strand of the 1x19 structure according to the present invention, as shown, the strand of the present invention is a lower edge (l2) consisting of six inner strands (d2) outside the center element (d1) ) Is formed and the upper edge (u) of 12 outer strands (d3) is formed thereon, whereby the entrance angle (α) of the upper edge (u) and the lower edge (l) is formed. There are technical features that are identical to each other.

On the other hand, Figure 3 (a), (b) is for explaining the entering angle (α) of the strand, (a) is showing the strand pitch (L, Lay Length), (b) is the layer core diameter (Dp) , Pitch Diameter).

Insertion angle (alpha) is based on following formula (1).

The same angle of incidence (α) between the upper edge (u) and the lower edge (l) means that the length of the inner layer wire (d2) and the length of the outer layer wire (d3) inserted in the longitudinal direction of the strand (S) are the same. When the tensile load is applied to the strands, the inner layer wire d2 and the outer layer wire d3 increase in the same ratio, so that the same tensile load acts on each wire of the inner layer wire d2 and the outer layer wire d3.

Accordingly, the cutting load is increased by the distribution of uniform force to each element wire, the fatigue stress is dispersed, and the timing of fatigue break is delayed, so that the service life of the strand or the wire rope using the strand of the present invention is increased.

On the other hand, in order to maintain the entrance angle of the upper and lower edges of the strand as described above, it is necessary to bring the pitch ratio of the upper and lower edges within a specific range, the pitch ratio of such a specific range is 45 ~ 55% of many tests As a result.

In other words, when the pitch ratio of the upper edge to the lower edge is maintained at 45 to 55%, the entrance angles of the upper edge and the lower edge can be taken to be the same.

In the strand of the present invention, by performing surface contact processing on the outer periphery, the fatigue resistance can be improved by expanding the contact area during contact with the roller or the sheave, and the strand subjected to the surface contact processing in this way has a multi-layered structure. When used in wire ropes, the contact area between adjacent strands will be enlarged, which will contribute to improved fatigue resistance.

The strand of the present invention can be used as a wire rope for the operation itself or as a core rope or inner and outer strands in a wire rope of a multi-layered structure.

FIG. 4 exemplarily shows a wire rope WR having an 8x7 + 1x19 structure in which a plurality of outer layer strands OS are twisted around using a strand S according to the present invention as a core rope CS. .

Embodiments of the present invention are as follows.

First, in the fabrication of strands having a 1x19 structure as shown in FIGS. 1 and 2, the center element d1 is 0.67 mm, the inner layer element d2 is 0.58 mm, and the outer layer element d3 has a diameter of 0.61 mm. An element wire having was used. After formation of the lower and upper edges, the strand nominal diameter was 3 mm.

In this case, the entrance angle of the lower and upper edges were to be 14.2 °, and the cutting load, the lead efficiency, and the durability were measured for the example specimens and the conventional specimens obtained according to the control point of the present invention. It is shown in Table 1.

division Example Comparative Example Insertion angle (°) Staging; 17.7, Ha Yeon; 13.3 Staging; 14.2, Ha Yeon; 14.2 Upper and lower pitch pitch ratio (%) 69.1 50.5 Cutting load (kgf) 890 999 Annual effectiveness rate (%) 88 92 Durability (times) 4500 6000

In Table 1, the upper and lower pitch ratios were measured by Equation 2 below.

In addition, the measured value of the annual efficiency in Table 1 is the number of times of bending at the time of breaking occurs by applying repeated bending using a bending tester.

As shown in Table 1, in the case of the embodiment strand according to the present invention in the mechanical properties related to fatigue resistance such as cutting load and durability significantly improved results compared to the strand produced by varying the entrance angle of the conventional upper and lower lead It can be seen that.

Meanwhile, in the exemplary strand of the present invention, the ratio (d1 / d2) of the center element to the inner layer was 1.150, the ratio of the inner layer and the outer layer (d2 / d3) was 0.951, and the spacing between the inner layer was 5.1. .

As described above, since the strands according to the present invention have the same entrance angles of the upper and lower edges, a uniform load distribution is achieved by the element wires constituting the upper edge and the element wires constituting the lower edge during the action of the tensile load. Since the load is prevented from falling as the load is concentrated on the element wire, the cutting force and the fatigue resistance are improved, thereby ultimately extending the life of the strand.

In addition, in the strand of the present invention, by controlling the diameter of the element wires constituting each layer, the compressive stress applied to the inner layer element wire having a structural characteristic interposed between the center element wire and the outer layer element wire and having a relatively large compressive stress action. The reduction in fatigue resistance is prevented.

The strand according to the present invention may be used as a wire rope itself, as well as a core rope or inner and outer layer strands of a wire rope composed of multilayer strands.

Claims (3)

Strand of 1x19 structure with 6 inner strands (d2) twisted around the center strand (d1) to form the lower strand (l) and 12 outer strands (d3) twisted around the lower strand to form the upper strand (u) The wire rope having excellent fatigue resistance according to claim 1, wherein the entrance angles of the upper edge (u) and the lower edge (l) are equal to each other, and the upper and lower edge pitch ratios are 45 to 55%. The method according to claim 1, wherein the ratio (d1 / d2) of the center element wire to the inner layer element wire is 1.13 to 1.17, the ratio of the ratio of the inner layer wire to the outer layer element wire (d2 / d3) is 0.90 to 0.98. Machine-operated wire rope excellent in fatigue resistance, characterized in that 4 to 6%. Fatigue resistance, characterized by comprising a core rope, inner layer or outer layer strands of 1x19 structure having the same entrance angle of the upper edge (u) and the lower edge (l) and the upper and lower pitch pitch ratio of 45 to 55% Excellent operating wire rope.