CN112359622A

CN112359622A - Outer unsaturated steel wire cord

Info

Publication number: CN112359622A
Application number: CN202011285707.3A
Authority: CN
Inventors: 刘祥; 马卫铭; 刘湘慧; 王燕; 曹恒祥
Original assignee: Jiangsu Xingda Steel Tyre Cord Co Ltd
Current assignee: Jiangsu Xingda Steel Tyre Cord Co Ltd
Priority date: 2020-11-17
Filing date: 2020-11-17
Publication date: 2021-02-12

Abstract

The invention discloses an outer-layer unsaturated steel wire cord which comprises a core strand steel wire, a middle-layer strand steel wire and an outer-layer strand steel wire, wherein the middle-layer strand steel wire is arranged outside the core strand steel wire along the circumferential direction, and the outer-layer strand steel wire is arranged outside the middle-layer strand steel wire along the circumferential direction. The fourteen outer strand steel wires are arranged, gaps among the steel wires are large, rubber can fully permeate into the middle strand steel wires, point contact friction among the steel wires at each layer due to insufficient permeation of the rubber is avoided, and the problem that the bearing capacity of a steel wire cord is invalid due to abrasion is avoided.

Description

Outer unsaturated steel wire cord

Technical Field

The invention relates to an outer unsaturated steel cord, belonging to the technical field of steel cords.

Background

The steel cord is an important component in a radial tire framework material, is a commonly used steel cord with a 3+9+15 x d structure of a radial tire, and is formed by twisting a core strand steel wire, a middle layer strand steel wire and an outer layer strand steel wire, wherein the diameters of the core strand steel wire, the middle layer strand steel wire and the outer layer strand steel wire are the same. (3 +9+ 15) x d1 has a twist direction of ZZZ, a lay length of 5.0/10.0/16.0mm or 6.3/12.5/18.0mm, the outer strand steel wires are arranged closely, gaps among the steel wires are small, and rubber cannot effectively permeate the middle strand steel wires to cause high air content in the cord.

During the use of the radial tire, the problem of the failure of the bearing capacity of the cord is easily caused by the insufficient strength of the steel wire cord or the corrosion and abrasion of the steel wire. The structure of the steel cord and the strength, bending stiffness and adhesive property with rubber thereof have direct influence on the tire, and the defects caused by unreasonable structural design cannot be completely compensated only by controlling the production process of the steel cord.

Disclosure of Invention

The invention aims to overcome the defects in the prior art, and provides an outer unsaturated steel cord which solves the defects that the strength of the steel cord is insufficient, the gaps between outer strands are small, and rubber cannot effectively permeate steel wires of middle strands, so that the air content in the cord is high.

In order to achieve the purpose, the technical scheme adopted by the invention is as follows:

providing an outer unsaturated steel cord characterized by comprising core strand steel wires, intermediate layer strand steel wires and outer layer strand steel wires, wherein the core strand steel wires comprise at least three strands of core strand first layer steel wires, the intermediate layer strand steel wires comprise at least ten strands of intermediate layer strand second layer steel wires, and the outer layer strand steel wires comprise at least fourteen strands of outer layer strand third layer steel wires;

the middle layer strand steel wires are arranged along the circumferential direction and are arranged on the periphery of the core strand steel wires, and the outer layer strand steel wires are arranged along the circumferential direction and are arranged on the periphery of the middle layer strand steel wires;

the diameter of the core strand steel wire is larger than that of the middle strand steel wire, and the diameter of the outer strand steel wire is the same as that of the middle strand steel wire.

Furthermore, the diameter range of the steel wires of the core strands is 0.19-0.26 mm, and the diameter range of the steel wires of the middle layer strands and the diameter range of the steel wires of the outer layer strands are 0.17-0.24 mm.

Further, the diameter of the steel wires of the outer core strand is at least more than 0.02mm compared with the diameter of the steel wires of the middle layer strand.

Further, the twisting direction of the steel wires of the core strand is the same as that of the steel wires of the middle layer strand and that of the steel wires of the outer layer strand.

Furthermore, the lay length of the third layer of steel wires of the outer layer strands is 1.333-1.50 times of that of the second layer of steel wires of the middle layer strands, and the lay length of the first layer of steel wires of the core strands is equal to that of the third layer of steel wires of the outer layer strands.

Further, the lay length of the first layer of steel wires of the core strand is larger than that of the second layer of steel wires of the middle layer strand.

Further, the steel wire gap L between the third layer of steel wires of the outer layer strand is more than 0.035 mm.

Further, the strength grades of the first layer steel wires of the core strands, the second layer steel wires of the middle layer strands and the third layer steel wires of the outer layer strands are any one of common strength NT, high strength HT, ultrahigh strength ST, ultrahigh strength UT or ultrahigh strength MT.

Compared with the prior art, the invention has the following beneficial effects:

(1) the fourteen strands of outer strand steel wires are arranged to increase gaps, so that rubber can fully permeate the middle strand steel wires, point contact friction between the steel wires at each layer due to insufficient permeation of rubber is avoided, and the problem that the bearing capacity of a steel cord line is invalid due to abrasion is further avoided;

(2) the invention improves the corrosion resistance, fatigue resistance, shock resistance and adhesion retention of the tire and prolongs the service life of the tire by changing the structure of the outer layer strand steel wire cord.

Drawings

FIG. 1 is a schematic cross-sectional view of an outer unsaturated steel cord of an embodiment of the present invention;

FIG. 2 is a cross-sectional schematic view of a steel cord of the prior art;

in the figure: 1. a core strand first layer of steel filaments; 2. a second layer of steel wires of the middle layer strand, 3 and a third layer of steel wires of the outer layer strand; 10. core strand steel wire; 20. middle layer strand steel wire; 30. outer layer strand steel wires; d1, core strand wire diameter; d2, intermediate ply wire diameter; d3, outer strand wire diameter; d4, wire diameter; l, steel wire gap.

Detailed Description

The invention is further described below with reference to the accompanying drawings. The following examples are only for illustrating the technical solutions of the present invention more clearly, and the protection scope of the present invention is not limited thereby.

In the description of the present invention, it is to be understood that the terms "first", "second", and the like are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implying any number of technical features indicated. Thus, a feature defined as "first," "second," etc. may explicitly or implicitly include one or more of that feature.

In the description of the present invention, it should be noted that, unless otherwise explicitly specified or limited, the terms "mounted," "connected," and "connected" are to be construed broadly, e.g., as meaning either a fixed connection, a removable connection, or an integral connection; can be mechanically or electrically connected; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meaning of the above terms in the present invention can be understood by those of ordinary skill in the art through specific situations.

As shown in fig. 1, which is a schematic cross-sectional view of an outer unsaturated steel cord according to an embodiment of the present invention, which is a 3 xd 1+10 xd 2+14 xd 3 steel cord, table 1 shows data parameters of examples 1-8 of an outer unsaturated steel cord according to the present invention, the steel cord having a circular cross-section, wherein the steel cord is formed by twisting a core strand steel wire 10 consisting of three core strands of first layer steel wires 1, an intermediate layer strand steel wire 20 consisting of ten intermediate layer strands of second layer steel wires 2, and an outer layer strand steel wire 30 consisting of fourteen outer layer strands of second layer steel wires 3,

the diameter range of the first layer of steel wires 1 of the core strand is 0.19-0.26 mm; the diameters of the middle layer strand second layer steel wire 2 and the outer layer strand second layer steel wire 3 are the same, and the diameter range is 0.17-0.24 mm. The core strand steel filaments 10 have the same twist direction as the steel filaments in the middle layer strand steel filaments 20 and the outer layer strand steel filaments 30. The steel wire gaps L between the outer layer strands and the third layer of steel wires 3 are at least larger than 0.035mm, forming a structure with unsaturated steel cords in the outer layer.

The invention overcomes the defects caused by unreasonable structural design of the steel cord by changing the structure of the outer steel cord, improves the strength, the glue permeability, the shock resistance and the fatigue resistance of the steel cord, reduces the air content between the steel cord strands of the tire, improves the strength grade of the tire cord and prolongs the service life of the tire.

In the embodiment of the present invention, the strength grades of the steel wires in the core strand steel wire 10 and the intermediate layer strand steel wire 20 and the outer layer strand steel wire 30 are normal strength NT, high strength HT, ultra-high strength ST, ultra-high strength UT, or ultra-high strength MT; the invention is suitable for any one of ordinary strength NT, high strength HT, ultrahigh strength ST, ultrahigh strength UT or ultrahigh strength MT, steel wires with different strength grades are woven and twisted, and the strength requirement, the glue permeation performance, the impact resistance and the fatigue resistance of the steel wire cord formed by weaving and twisting can be improved.

TABLE 1

The first embodiment is as follows:

in the examples of the present invention, the 3 × 0.26+10+14 × 0.24HT structure was used for a steel cord for radial tire reinforcement. The diameter of the core strand steel wire diameter d1 in the core strand 10 is at least greater than 0.02mm than the diameter d2 of the intermediate layer strand in the intermediate layer strand 20, the diameter of the core strand first layer steel wire 1 in the steel cord is 0.26mm, the diameters of the intermediate layer strand second layer steel wire 2 and the outer layer strand second layer steel wire 3 are both 0.24mm, the twisting pitch of the core strand first layer steel wire 1 in a twisting mode is 18.0mm, the twisting pitch of the intermediate layer strand second layer steel wire 2 in a twisting mode is 12.5mm, and the twisting pitch of the outer layer strand second layer steel wire 3 in a twisting mode is 18.0 mm. The core strand steel wires 10 and the middle and outer

strand steel wires

20 and 30 adopt the same twisting direction, and the twisting direction is Z twisting.

Fig. 2 is a schematic cross-sectional view of a steel cord in the prior art, which is a schematic cross-sectional view of a commonly used 3+9+15 × 0.245HT structural steel cord, the diameter of the 3+9+15 × 0.245HT structural steel cord is 1.51mm, the diameters of the core strand steel wire 10, the middle strand steel wire 20 and the outer strand steel wire 30 are the same and are the steel wire diameter d4, the value is 0.245mm, and the core strand steel wire 10, the middle strand steel wire 20 and the outer strand steel wire 30 are all ZZZ twisted.

Table 2 is a table comparing the performance indexes of the 3+9+15 × 0.245HT structural steel cord commonly used in the radial tire in the prior art and the 3 × 0.26+10+14 × 0.24HT structural steel cord of the embodiment of the present invention:

TABLE 2

The 3+9+15 × 0.245HT structural steel cord is a structural steel cord commonly used in the prior art, and it can be seen from table 2 that the diameter of the 3+9+15 × 0.245HT structural steel cord is 1.51mm, the diameters of the core strand steel wire 10, the intermediate layer strand steel wire 20 and the outer layer strand steel wire 30 are both 0.245mm, the core strand steel wire 10, the intermediate layer strand steel wire 20 and the outer layer strand steel wire 30 are all Z-twisted, the lay length of the core strand steel wire 10 is 6.3mm, the lay length of the intermediate layer strand steel wire 20 is 12.5mm, the lay length of the outer layer strand steel wire 30 is 18.0mm, the breaking force is not less than 3730N, the breaking force/linear density is 363.5N/(/ g/m), and the adhesive force is not less than 1600N/25 mm.

The diameter of the steel cord of the first embodiment of the invention is 1.52mm, the diameters of core strand steel wires 10 are both 0.26mm, the diameters of middle layer strand steel wires 20 and outer layer strand steel wires 30 are both 0.24mm, the diameters of the core strand steel wires 10, the middle layer strand steel wires 20 and the outer layer strand steel wires 30 are all Z-twisted, the lay length of the core strand steel wires 10 is 18.0mm, the lay length of the middle layer strand steel wires 20 is 12.5mm, the lay length of the outer layer strand steel wires 30 is 18.0mm, the breaking force is larger than or equal to 3730N, the breaking force/linear density is 374N/(mm), and the adhesive force is larger than or equal to 1600N/25 mm. Compared with the prior art, the first embodiment of the invention adopts the steel wires with the same strength grade, and improves the strength, the glue permeation rate and the fatigue resistance of the cord by increasing the diameter and the lay length of the core strand, reducing the outer layer strand and increasing the number of the single wires of the middle layer strand.

Example two:

in the examples of the present invention, the 3 × 0.24+10+14 × 0.22ST structure was used for a steel cord for radial tire reinforcement. The diameter of the core strand steel wire diameter d1 in the core strand 10 is at least greater than 0.02mm than the diameter d2 of the intermediate layer strand in the intermediate layer strand 20, the diameter of the core strand first layer steel wire 1 in the steel cord is 0.24mm, the diameters of the intermediate layer strand second layer steel wire 2 and the outer layer strand second layer steel wire 3 are both 0.22mm, the twisting pitch of the core strand first layer steel wire 1 in a twisting mode is 18.0mm, the twisting pitch of the intermediate layer strand second layer steel wire 2 in a twisting mode is 12.5mm, and the twisting pitch of the outer layer strand second layer steel wire 3 in a twisting mode is 18.0 mm. The core strand steel wires 10 and the middle and outer

strand steel wires

Table 3 is a table comparing the performance indexes of the 3+9+15 × 0.225ST structural steel cord commonly used in radial tires in the prior art and the two 3 × 0.24+10+14 × 22ST structural steel cords of the example of the present invention:

TABLE 3

Item	3+9+15×0.225ST	3×0.24+10+14×0.22ST
			Cord diameter (+ -5%)/mm	1.39	1.39
Direction of twist	ZZZ	ZZZ
			Lay length (± 5%)/mm	6.3/12.5/18.0/	18.0/12.5/18.0
Minimum breaking force/N	3485	3500
			Linear density (. + -. 5%)/g/m	8.63	8.36
Breaking force/linear density N/(g/m)	403.8	418.6
			Adhesion (N/25mm)	1300	1300

The 3+9+15 × 0.225ST structural steel cord is a structural steel cord commonly used in the prior art, and it can be seen from table 3 that the diameter of the 3+9+15 × 0.225ST structural steel cord is 1.39mm, the diameters of the core strand steel wire 10, the intermediate strand steel wire 20 and the outer strand steel wire 30 are both 0.225mm, the diameters of the core strand steel wire 10, the intermediate strand steel wire 20 and the outer strand steel wire 30 are all Z-twisted, the lay length of the core strand first layer steel wire 1 is 6.3mm, the lay length of the intermediate layer strand second layer steel wire 2 is 12.5mm, the lay length of the outer strand second layer steel wire 3 is 18.0mm, the breaking force is not less than 3485N, the breaking force/wire density is 403.8/(/ g/m), and the adhesive force is not less than 1300N/25 mm.

The steel cord of the second example of the present invention has a diameter of 1.39mm, the core strand steel wires 10 each have a diameter of 0.24mm, the intermediate layer strand steel wires 20 and the outer layer strand steel wires 30 each have a diameter of 0.22mm, the core strand steel wires 10, the intermediate layer strand steel wires 20 and the outer layer strand steel wires 30 each have Z-lay, the lay length of the core strand steel wires 10 is 18.0mm, the lay length of the intermediate layer strand steel wires (20) is 12.5mm, the lay length of the outer layer strand steel wires (30) is 18.0mm, the breaking force is not less than 3500N, the breaking force/linear density is 418.6N/(mm), and the adhesive force is not less than 1300N/25 mm.

Compared with the two, the second embodiment of the invention adopts the steel wires with the same strength grade, and improves the strength, the glue permeation rate and the fatigue resistance of the cord by increasing the diameter and the lay length of the core strand, reducing the outer layer strand and increasing the number of the single wires of the middle layer strand.

Example three:

in the examples of the present invention, the 3 × 0.215+10+14 × 0.195ST structure was used for a steel cord for radial tire reinforcement. The diameter of the core strand steel wire diameter d1 in the core strand 10 is at least greater than 0.02mm than the diameter d2 of the intermediate layer strand in the intermediate layer strand 20, the diameter of the core strand first layer steel wire 1 in the steel cord is 0.215mm, the diameters of the intermediate layer strand second layer steel wire 2 and the outer layer strand second layer steel wire 3 are both 0.195mm, the twisting pitch of the core strand first layer steel wire 1 in a twisting mode is 16.0mm, the twisting pitch of the intermediate layer strand second layer steel wire 2 in a twisting mode is 12.0mm, and the twisting pitch of the outer layer strand second layer steel wire 3 in a twisting mode is 16.0 mm. The core strand steel wires 10 and the middle and outer

strand steel wires

Table 4 is a table comparing the performance indexes of the 3+9+15 × 0.20ST structural steel cord commonly used in the radial tire of the prior art and the three 3 × 0.215+10+14 × 0.195ST structural steel cords of the example of the present invention:

TABLE 4

The 3+9+15 × 0.20ST structural steel cord is a structural steel cord commonly used in the prior art, and it can be seen from table 4 that the diameter of the 3+9+15 × 0.20ST structural steel cord is 1.22mm, the diameters of the core strand steel wire 10, the intermediate layer strand steel wire 20 and the outer layer strand steel wire 30 are both 0.20mm, the diameters of the core strand steel wire 10, the intermediate layer strand steel wire 20 and the outer layer strand steel wire 30 are all Z-twisted, the lay length of the core strand first layer steel wire 1 is 6.3mm, the lay length of the intermediate layer strand second layer steel wire 2 is 12.5mm, the lay length of the outer layer strand second layer steel wire 3 is 15.0mm, the breaking force is not less than 2750N, the breaking force/linear density is 404.4/(/ g/m), and the adhesive force is not less than 500N/12.5 mm.

The steel cord of the third example of the present invention has a diameter of 1.23mm, the core strand steel wires 10 each have a diameter of 0.215mm, the intermediate layer strand steel wires 20 and the outer layer strand steel wires 30 each have a diameter of 0.195mm, the core strand steel wires 10, the intermediate layer strand steel wires 20 and the outer layer strand steel wires 30 each have Z-lay, the lay length of the core strand steel wires 10 is 16.0mm, the lay length of the intermediate layer strand steel wires 20 is 12.0mm, the lay length of the outer layer strand steel wires 30 is 16.0mm, the breaking force is not less than 2800N, the breaking force/linear density is 425.5N/(mm), and the adhesive force is not less than 500N/12.5 mm.

Compared with the two, the third embodiment of the invention adopts the steel wires with the same strength grade, and improves the strength, the glue permeation rate and the fatigue resistance of the cord by increasing the diameter and the lay length of the core strand, reducing the outer layer strand and increasing the number of the single wires of the middle layer strand.

As can be seen from the comparison, when the radial tire with the same density is manufactured, the strength of the radial tire manufactured by the invention is improved by 3 percent compared with the strength of the radial tire manufactured by the prior art, and the rubber permeability and the fatigue resistance of the cord are greatly improved. The invention can effectively reduce the production cost of the radial tire and prolong the service life of the radial tire of the engineering vehicle.

The embodiment of the present invention is only an example, and according to different applications, the 3 xd 1+10 xd 2+14 xd 3 structure of the present invention, the steel wires in the core strand steel wires 10, the steel wires in the middle layer strand steel wires 20 and the outer layer strand steel wires 30 can be matched by using different wire diameters and strengths, and the twisting direction can be divided into zz z and SSS or zz s and SSZ.

The above description is only a preferred embodiment of the present invention, and it should be noted that, for those skilled in the art, several modifications and variations can be made without departing from the technical principle of the present invention, and these modifications and variations should also be regarded as the protection scope of the present invention.

Claims

1. An outer unsaturated steel cord characterized by comprising core strand steel filaments (10), intermediate layer strand steel filaments (20) and outer layer strand steel filaments (30), said core strand steel filaments (10) comprising at least three core strand first layer steel filaments (1), said intermediate layer strand steel filaments (20) comprising at least ten intermediate layer strand second layer steel filaments (2), said outer layer strand steel filaments (30) comprising at least fourteen outer layer strand third layer steel filaments (3);

the middle layer strand steel wires (20) are arranged along the circumferential direction and are arranged on the periphery of the core strand steel wires (10), and the outer layer strand steel wires (30) are arranged along the circumferential direction and are arranged on the periphery of the middle layer strand steel wires (20);

the core strand steel wire (10) has a core strand steel wire diameter (d 1) larger than the intermediate strand steel wire diameter (d 2) of the intermediate strand steel wire (20), and the outer strand steel wire diameter (d 3) of the outer strand steel wire (30) is the same as the intermediate strand steel wire diameter (d 2).

2. An outer unsaturated steel cord according to claim 1 characterized in that said core strand steel wire diameter (d 1) ranges from 0.19 to 0.26mm and said intermediate layer strand steel wire diameter (d 2) and outer layer strand steel wire diameter (d 3) ranges from 0.17 to 0.24 mm.

3. An outer unsaturated steel cord according to claim 2 characterized in that said outer core strand steel wire diameter (d 1) is at least larger than 0.02mm compared to the middle layer strand steel wire diameter (d 2).

4. An outer unsaturated steel cord according to claim 1 characterized in that said core strand steel filaments (10) have the same twist direction as the middle strand steel filaments (20) and the outer strand steel filaments (30).

5. An outer unsaturated steel cord according to claim 1 characterized in that said outer ply third layer of steel filaments (3) has a lay length 1.333 to 1.50 times the lay length of the middle ply second layer of steel filaments (2), said core ply first layer of steel filaments (1) having a lay length equal to the lay length of the outer ply third layer of steel filaments (3).

6. An outer unsaturated steel cord according to claim 1 characterized in that the steel filament gap (L) between the outer strand third layer steel filaments (3) is more than 0.035 mm.

7. An outer unsaturated steel cord according to claim 1 characterized in that said core strand first layer steel filaments (1), intermediate layer strand second layer steel filaments (2) and outer layer strand third layer steel filaments (3) have a strength grade of any of normal strength NT, high strength HT, ultra high strength ST, ultra high strength UT or ultra high strength MT.