A steel radial tire for load - carrying construction machinery

Abstract

The present invention relates to an all-steel radial tire for off-road heavy-duty engineering machinery. The belt structure of this new structure is composed of 5 layers of steel cord fabrics. The first layer of steel cord fabric layer is arranged in a layer-by-layer manner on the carcass, and the included angle between it and the center line of the tire tread is 23±1°. The second layer of steel cord fabric layer is arranged in a layer-by-layer manner on the first layer of steel cord fabric, and the included angle between it and the center line of the tire tread is 17±1°. The third layer of steel cord fabric and the fourth layer of steel cord fabric are arranged in a circumferential layer-by-layer manner on the second layer of steel cord fabric in a manner that the included angle between them and the center line of the tire tread is 0°. The fifth layer of steel cord fabric layer is arranged in a layer-by-layer manner on the fourth layer of 0-degree steel cord fabric, and the included angle between it and the center line of the tire tread is 40±1°. Compared with the prior art, the structure of the present invention can effectively relieve the deformation of the tire caused by long-term flexure deformation under the heavy load state of the tire, and the problems such as shoulder void and crown void caused by large tire heat generation.

Description

Technical Field

[0001] The invention relates to an off-road all-steel load-carrying engineering machinery radial tire (OTR), and in particular to an application of a new structure (adopting a two-layer 0° belt layer structure) in an OTR tire. Background Art

[0002] For off-road all-steel radial tires (OTR), 70% of the load is borne by the belt layer, especially the middle working layer cord.

[0003] The belt ply refers to the material layer under the tread base of the radial tire, which tightens the carcass along the circumferential direction of the tread centerline. In addition to mitigating the impact, it mainly tightens the carcass and carries the load. It is composed of high-strength, high-modulus and small-angle arranged cords as its reinforcement material, and is covered with a cord fabric compounded with high-strength and high-hardness rubber.

[0004] At present, the traditional belt layer structure mainly uses 4 layers of steel wire covered with rubber cord fabric, and each layer of steel wire cord fabric is cross-laminated together at a small angle and in different arrangement directions.

[0005] Off-road all-steel load-bearing radial tires (OTR) are mainly used for mining machinery load-bearing vehicles under harsh operating conditions. They require strong load-bearing capacity, puncture resistance, cut resistance, and low heat generation. The belt layer structure currently used has insufficient puncture resistance (tire blowout phenomenon), and the tire contours are greatly deformed before and after use (high air pressure and high load), which results in high heat generation and a short tire life cycle.

[0006] Patent CN201420487699.4 discloses a steel radial light truck tire, including a tread, a sidewall, a bead, a carcass ply, and a belt layer. It is characterized in that: the belt layer includes a 1# belt layer, a 2# belt layer, a 3# belt layer, and a 4# belt layer. The belt layer adopts a variable angle design. The 4# belt layer is narrow in width and uses one layer of belt layer and one layer of tackifying and reinforcing film. This utility model claims that the service life of the tire is extended by 1 to 3 times, the rolling resistance of the tire is reduced by 28% (green tire), fuel is saved by 6% - 6.5%, the puncture resistance performance is greatly improved in a harsh multi-rock environment, and when operating in a reclamation project, the crown puncture resistance performance is very good, and puncture and blowout are reduced. However, the included angle between the cord of the 1# belt layer and the center line of the tire crown surface is 22°, the included angle between the cord of the 2# belt layer and the center line of the tire crown surface is 27°, the included angle between the cord of the 3# belt layer and the center line of the tire crown surface is 20°, the included angle between the cord of the 4# belt layer and the center line of the tire crown surface is 16°, and the included angle between the cord of the 5# belt layer and the center line of the tire crown surface is 15°. However, although the included angle of the belt ply cord of this product is changed, after the tire is inflated, as the pressure increases, the angle will tend to change towards the 0° direction of the tire tread center line, resulting in shoulder void or crown void phenomena due to large heat generation caused by deformation in the later stage of tire use. Moreover, the above-mentioned patent product of the light truck radial tire of TBR and the new structure product of the off-road OTR have essential differences in the use environment. Summary of the Invention

[0007] The purpose of the present invention is to overcome the deformation defects before and after use of the above-mentioned existing technologies, and provide a belt layer structure for a new type of belt layer structure radial tire, which can effectively relieve the deformation of the tire caused by long-term flexural deformation under the heavy load state, and the shoulder void and crown void and other phenomena caused by large heat generation of the tire.

[0008] The purpose of the present invention can be achieved by the following technical solutions: an off-road all-steel heavy-duty construction machinery radial tire with a new structure (adopting a two-layer 0° belt layer structure). The belt layer structure of this tire is composed of 5 layers of steel cord fabrics. The first layer of steel cord fabric is arranged on the carcass, and the included angle between it and the center line of the tire tread is 23 ± 1°. The second layer of steel cord fabric is arranged on the first layer of steel cord fabric, and the included angle between it and the center line of the tire tread is 17 ± 1°. The third layer of steel cord fabric and the fourth layer of steel cord fabric are arranged circumferentially in sequence on the second layer of steel cord fabric in a manner that the included angle with the center line of the tire tread is 0°. The fifth layer of steel cord fabric is arranged on the fourth layer of steel cord fabric, and the included angle between it and the center line of the tire tread is 40 ± 1°.

[0009] The included angle setting directions between the first layer of steel cord fabric and the second layer of steel cord fabric and the center line of the tire tread are opposite. That is, if the included angle between the first layer of steel cord line and the center line of the tire tread is 23±1° counted from left to right, then the included angle between the second layer of steel cord line and the center line of the tire tread is 17±1° counted from right to left.

[0010] The key third layer of steel cord fabric and the fourth layer of steel cord fabric have the same width and are circumferentially arranged between the second layer of steel cord fabric and the fifth layer of steel cord fabric in a manner of having an included angle of 0° with the center line of the tire tread, mainly playing a load-bearing role. It is composed of cord fabric with high strength, high modulus and small-angle arrangement as its reinforcing material, and is simultaneously covered with cord fabric compounded with high modulus and high hardness rubber compound.

[0011] The included angle setting directions between the fifth layer of steel cord fabric and the second layer of steel cord fabric and the center line of the tire tread are opposite. That is, the included angle between the fifth layer of steel cord line and the center line of the tire tread is 40±1° counted from left to right.

[0012] The third layer of steel cord fabric and the fourth layer of steel cord fabric use high-elongation cord, with a density of 45 cords / 100mm and a thickness of 2.2mm and a width of 252mm.

[0013] The first layer of steel cord fabric uses ultra-high-strength steel cord line, with a density of 48 cords / 100mm of steel wire.

[0014] The fifth layer of steel cord fabric uses steel cord line, with a high elongation density of 45 cords / 100mm of steel wire.

[0015] A tread is arranged outside the fifth layer of steel cord fabric, and a carcass is arranged inside the first layer of steel cord fabric.

[0016] The tread uses a mixed formula of low heat-generating natural rubber and styrene-butadiene rubber. The specific formula includes the following components in parts by weight: 10 - 30 parts of natural rubber, 70 - 90 parts of emulsion-polymerized styrene-butadiene rubber, 10 - 40 parts of high-structure super abrasion-resistant carbon black, 20 - 40 parts of low-structure high-abrasion-resistant carbon black, 5 - 15 parts of precipitated high-dispersion silica, 3 - 6 parts of zinc oxide, 1 - 3 parts of stearic acid, 1 - 3 parts of protective wax, 2 - 7 parts of antioxidant, 2 - 6 parts of aromatic oil, 1 - 4 parts of tackifying resin, 1 - 2 parts of physical peptizer, 0.1 - 0.6 parts of accelerator D, 0.5 - 2 parts of ordinary sulfur, 0.5 - 2 parts of sulfenamide accelerator CZ, 0.1 - 0.4 parts of scorch retarder CTP. When preparing, the raw materials in the above weight ratios are processed by a mixer to make a mixed rubber, and the mixed rubber is made into a tread semi-finished product by extrusion with a double compound extruder. The tread semi-component is adhered to the belt layer on a molding machine to make a tire blank, and the green tire blank is vulcanized into a finished tire by a vulcanizer.

[0017] The carcass uses 55 high-strength and high-density steel wires per 100 mm, and the bead uses φ1.55 high-strength steel wires.

[0018] Compared with the prior art, the present invention has the following advantages:

[0019] 1. The belt structure adopted by the present invention consists of 5 layers. The second, third, and fourth steel cord plies bear the load. The first steel cord ply is arranged at a large angle to play a transitional role, and the fifth steel cord ply plays a role in protecting the working layer. Compared with the traditional structure, the new structure product has the following improvements: the deformation rate of the outer diameter of the tire after durability is reduced by 30%, the durability time is increased by 40%, the tread temperature is reduced by 15%, the wear resistance is increased by 20%, the load-bearing capacity is increased by 50%, and the puncture resistance is increased by more than 30%.

[0020] 2. The third and fourth steel cord plies of the present invention are arranged circumferentially in the 0° manner (the angle with the center line of the tire tread) for 2 layers. After the tire is inflated, the angle will no longer change, which can effectively relieve the deformation of the tire caused by long-term bending deformation under the heavy load state, and the problems such as shoulder void and crown void caused by high heat generation of the tire. At the same time, when this product is used in low-speed and harsh environments, it can avoid the shoulder void and delamination phenomena caused by high heat generation. Although the angle of the belt ply cord of the traditional product is changed, as the pressure increases after the tire is inflated, the angle will tend to change towards the 0° direction of the tire tread center line, resulting in shoulder void or crown void phenomena due to deformation and high heat generation in the later stage of tire use.

[0021] 3. The present invention can effectively resist the damage of external sharp objects to the crown of the tire, improve the puncture resistance of the tire, reduce the problem of delamination caused by heat generation, and can greatly improve the service life of the tire, meeting the use requirements of off-road mining vehicles.

[0022] 4. The belt structure of the present invention does not need to be provided with reinforcing rubber sheets, etc., saving raw materials and process procedures and reducing costs.

[0023] 5. The tread adopted by the present invention has good wear resistance, excellent puncture resistance, low heat generation, high tensile strength and tear strength, good thermal stability and fatigue resistance, can effectively reduce the non-wear phenomenon caused by pattern chunking, is suitable for the use requirements of mining and engineering vehicles for tires, and has excellent performance during use, improving the use safety and life of the tire. Description of the Drawings

[0024] Figure 1 It is a half-sectional view of the tire adopting the belt structure of the present invention.

[0025] 1 - The first steel cord ply, 2 - The second steel cord ply, 3 - The third steel cord ply, 4 - The fourth steel cord ply, 5 - The fifth steel cord ply, 6 - The carcass, 7 - The tread. Detailed Embodiments

[0026] The present invention will be described in detail below with reference to the accompanying drawings and specific embodiments.

[0027] Embodiment 1

[0028] As Figure 1 shown, a non-road type all-steel radial load engineering machinery tire with a new structure (adopting a two-layer 0° belt layer structure), the tire includes a carcass 6, a tread 7, and a belt layer disposed between the carcass 6 and the tread 7. The belt layer structure is composed of 5 layers of steel cord fabrics. The first layer of steel cord fabric 1 is arranged on the carcass 6, and the included angle between it and the center line of the tire tread is 23° (that is, the included angle between the first layer of steel cord line 1 and the center line of the tire tread is counted as 23° from left to right). The second layer of steel cord fabric 2 is arranged on the first layer of steel cord fabric, and the included angle between it and the center line of the tire tread is 17° (the included angle between the second layer of steel cord line 2 and the center line of the tire tread is counted as 17° from right to left). The third layer of steel cord fabric 3 and the fourth layer of steel cord fabric 4 are sequentially arranged circumferentially on the second layer of steel cord fabric row in a manner that the included angle with the center line of the tire tread is 0°. The fifth layer of steel cord fabric 5 is arranged on the fourth layer of steel cord fabric, and the included angle between it and the center line of the tire tread is 40° (the included angle between the fifth layer of steel cord line 5 and the center line of the tire tread is counted as 40° from left to right).

[0029] When the above belt layer structure is used in a tire, the tread of the tire adopts a mixed formula of low heat generation natural rubber and styrene-butadiene rubber. The tread formula contains the following components in parts by weight: 20 parts of natural rubber, 80 parts of emulsion polymerized styrene-butadiene rubber, 20 parts of high structure super abrasion resistant carbon black, 30 parts of low structure high abrasion resistant carbon black, 10 parts of precipitated high dispersion silica, zinc oxide: 5 parts, stearic acid: 2 parts, protective wax: 2 parts, antioxidant: 5 parts, aromatic oil: 5 parts, tackifying resin: 2 parts, physical peptizer: 1.5 parts, accelerator D: 0.3 parts, ordinary sulfur: 1 part, secondary sulfonamide accelerator CZ: 1 part, anti-scorching agent CTP: 0.3 parts.

[0030] During preparation: the raw materials with the above weight ratio are processed into a rubber mix by an internal mixer, the rubber mix is extruded into a tread semi-finished product by a double compound extruder, the tread semi-component is attached to the belt layer on a molding machine to form a tire embryo, and the raw embryo is vulcanized into a finished tire by a vulcanizer. The tread formula uses a certain proportion of latex polystyrene butadiene rubber, uses a high-structure super-wear-resistant carbon black (high-structure super-wear-resistant carbon black N-234 produced by Cabot Chemical (Tianjin) Co., Ltd.), greatly improves the puncture resistance and wear resistance of the tread formula on bad roads, uses a certain proportion of white carbon black (precipitated white carbon black 822MP produced by Wuxi Hengcheng Silicon Industry), improves the tear resistance of the tread formula, uses white carbon black, and simultaneously uses a low-structure high-wear-resistant carbon black (commercially available N326), reduces the heat generation of the tread formula.

[0031] The tread formula has excellent wear resistance and puncture resistance, low heat generation, high tensile strength and tear strength, good thermal stability and fatigue resistance, and can effectively reduce the wear-resistant phenomenon caused by tread blocks being bitten off. It is suitable for the tire use requirements of mining and engineering vehicles, has excellent performance during use, and improves the safety and life of the tire.

[0032] The carcass is made of ultra-high strength and density 55 steel wires / 100mm, the tire bead is made of φ1.55 high-strength steel wire, the first and second belt layers are made of ultra-high strength and density 48 steel wires / 100mm, the third and fourth belt layers are made of special two layers of 0° with high tensile density 45 steel wires / 100mm, and the fifth layer is made of high tensile density 45 steel wires / 100mm.

[0033] Table 1 Comparison of test results of tires with conventional structure and structure of Example 1

[0034]

[0035] In the above comparison table, the traditional structure of CN201420487699.4 is adopted, and the inflated outer edge diameter changes from 1493 to 1508.9 after durability, which is much larger than the change range of the present invention (the present invention changes from 1490.8 to 1497.1), indicating that the tire puncture resistance of the present invention is better than the traditional structure of the non-zero degree belt layer in the prior art CN201420487699.4.

[0036] The endurance test conditions are as follows: keep the speed at 20km / h constant, load 65% for the first 10h, load 85% for the second 10h, load 100% for the third 10h, and increase the load by 10% every 5h after 30h until damage; the load is based on the maximum load of a single tire, and the air pressure is based on the maximum air pressure of a single tire. The ambient temperature is 38±3°, and the tire-rim assembly is parked at the ambient temperature for 24h.

[0037] Compared with the traditional structure, in Example 1, after the tire is durable, the deformation rate of the outer diameter of the tire is reduced by 30%, the durability time is increased by 40%, the tread temperature is reduced by 15%, the wear resistance is increased by 20%, the load-bearing capacity is increased by 50%, and the puncture resistance is increased by more than 30%.

[0038] Example 2

[0039] The tread formula of the tire contains the following components in parts by weight: 10 parts of natural rubber, 70 parts of emulsion-polymerized styrene-butadiene rubber, 40 parts of high-structure super abrasion furnace black, 40 parts of low-structure high abrasion furnace black, 5 parts of precipitated highly dispersed silica, 3 parts of zinc oxide, 1 part of stearic acid, 1 part of protective wax, 2 parts of anti-aging agent, 2 parts of aromatic oil, 1 part of tackifying resin, 1 part of physical peptizer, 0.1 part of accelerator D, 0.5 part of common sulfur, 0.5 part of sulfenamide accelerator CZ, and 0.1 part of anti-scorching agent CTP. The rest is the same as in Example 1. The obtained tire, compared with the traditional structure, can effectively relieve the deformation of the tire caused by long-term flexure deformation under the heavy load state of the tire, and the problems such as shoulder void and crown void caused by the large heat generation of the tire. It can effectively resist the damage of external sharp objects to the crown of the tire, improve the puncture resistance of the tire, reduce the problem of delamination caused by heat generation, greatly improve the service life of the tire, and meet the use requirements of off-road mining vehicles.

[0040] Example 3

[0041] The tread formula of the tire contains the following components in parts by weight: 30 parts of natural rubber, 90 parts of emulsion-polymerized styrene-butadiene rubber, 10 parts of high-structure super abrasion furnace black, 20 parts of low-structure high abrasion furnace black, 15 parts of precipitated highly dispersed silica, 6 parts of zinc oxide, 3 parts of stearic acid, 3 parts of protective wax, 7 parts of anti-aging agent, 6 parts of aromatic oil, 4 parts of tackifying resin, 2 parts of physical peptizer, 0.6 part of accelerator D, 2 parts of common sulfur, 2 parts of sulfenamide accelerator CZ, and 0.4 part of anti-scorching agent CTP.

[0042] The rest is the same as in Example 1. The obtained tire, compared with the traditional structure, can effectively relieve the deformation of the tire caused by long-term flexure deformation under the heavy load state of the tire, and the problems such as shoulder void and crown void caused by the large heat generation of the tire. It can effectively resist the damage of external sharp objects to the crown of the tire, improve the puncture resistance of the tire, reduce the problem of delamination caused by heat generation, greatly improve the service life of the tire, and meet the use requirements of off-road mining vehicles.

Claims

1. A steel radial tire for load-carrying engineering machinery, characterized in that, The belt structure of the tire consists of 5 layers of steel cord fabric. The first layer of steel cord fabric is arranged on the carcass, and the angle between it and the center line of the tire tread is 23±1°. The second layer of steel cord fabric is laminated on the first layer of steel cord fabric, and the angle between it and the center line of the tire tread is 17±1°. The third layer of steel cord fabric and the fourth layer of steel cord fabric are arranged on the second layer of steel cord fabric in turn at an angle of 0° with respect to the center line of the tire tread. The fifth layer of steel cord fabric is laminated on the fourth layer of 0° steel cord fabric, and the angle between it and the center line of the tire tread is 40±1°; The angles between the first layer of steel cord fabric and the second layer of steel cord fabric and the center line of the tire tread are set in opposite directions; The third layer of steel cord fabric and the fourth layer of steel cord fabric are arranged on the second layer of steel cord fabric in a circumferential lamination manner at an angle of 0° with respect to the center line of the tire tread.

2. The all-steel radial tire for load-carrying engineering machinery according to claim 1, wherein, The angles between the fifth layer of steel cord fabric and the second layer of steel cord fabric and the center line of the tire tread are set in opposite directions.

3. The all-steel radial tire for load-carrying engineering machinery according to claim 1, characterized in that, The third layer of steel cord fabric and the fourth layer of steel cord fabric have the same width and are arranged circumferentially between the second layer of steel cord fabric and the fifth layer of steel cord fabric at an angle of 0° with respect to the center line of the tire tread.

4. The all-steel radial tyre for load-carrying engineering machinery according to claim 1 or 3, wherein, The third layer of steel cord fabric and the fourth layer of steel cord fabric use high-elongation cord, with a density of 45 cords / 100mm and a thickness of 2.2mm and a width of 252mm.

5. The all-steel radial tire for load-carrying engineering machinery according to claim 1, wherein The first layer of steel cord fabric uses ultra-high-strength steel cord, with a density of 48 cords / 100mm of steel wire.

6. The all-steel radial tire for load-carrying engineering machinery according to claim 1, characterized in that, The fifth layer of steel cord fabric uses steel cord, with a high-stretch density of 45 cords / 100mm of steel wire.

7. The all-steel radial tyre for load-carrying engineering machinery according to claim 1, wherein A tread is provided on the outside of the fifth layer of steel cord fabric, and a carcass is provided on the inside of the first layer of steel cord fabric.

8. The all-steel radial tire for load-carrying construction machinery according to claim 7, wherein, The tread uses a mixed formula of low-heat-generating natural rubber and styrene-butadiene rubber. The carcass uses steel wire with a density of 55 cords / 100mm, and the bead uses φ1.55 steel wire.

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