All-steel truck radial tire

Abstract

The invention discloses an all-steel truck radial tire, and relates to the technical field of radial tires. The outer contour section width SW, the lower side plate height LSH and the tire bead part positioning line width TTZ of the tire are optimally designed, and under the constraint of given technical parameters, the stress deformation of the tire bead part of the tire is small; meanwhile, in the structural design, the tire body cord fabric endpoint height HSC, the chafer outer side endpoint height HWC.O, the chafer inner side endpoint height HWC.I, the hard apex upper endpoint height HHBF, a tire bead part integral reinforcing layer arranged among the tire body cord fabric, the apex and the steel wire ring, and a tire bead part integral reinforcing layer arranged among the tire body cord fabric, the apex and the steel wire ring are matched; the tire body cord fabric and the chafer inner side reinforcing layer arranged between the tire body cord fabric and the inner side end point of the chafer are optimally designed, and new requirements on the strength of the reinforcing layer and the strength and modulus of cord thread coating rubber are met; deformation and modulus matching of the soft apex and the hard apex are deeply explored and verified on formula materials, so that stress deformation of the whole tire bead part is reduced, early-stage cracks at a tire body cord fabric end point, an outer / inner side end point of a tire chafer, an upper end point of the hard apex and a widest position of a steel wire ring are reduced, and the service life of the tire is effectively prolonged.

Description

Technical Field

[0001] The invention relates to the technical field of radial tires, and in particular to an all-steel load-bearing radial tire capable of improving tire bead durability. Background Art

[0002] In the heavy-duty market, due to the high load use environment, tire bead failure is one of the most common failure phenomena, such as outer bead cracks, inner bead cracks, bead cut explosions, etc., which affect the service life of the tire. To deal with these problems, the countermeasures usually taken in tire design are generally in the following two directions: ① By increasing the height of the steel wire material to increase the bead stiffness; ② By adding a reinforcement layer of steel wire material to increase the bead stiffness.

[0003] 1. Chinese invention patent CN106956551A discloses a fiber cord radial tire, which adds a layer of fiber cord outside the bead and the apex rubber. Its structural characteristics are that the height of the end point of the carcass cord is higher than the height of the outer end point of the bead chafer, the height of the outer end point of the fiber cord is higher than the end point of the carcass cord, and the height of the inner end point of the fiber cord is higher than the height of the inner end point of the bead chafer. It can form a uniform transition of material hardness and rigidity between the apex rubber and the carcass cord, and reduce the shear stress of the carcass cord end point at the same time, solve the problem of failure caused by insufficient bead strength or sudden change in rigidity during use, thereby improving the driving safety and service life of the tire. (This tire structure in which the height of the carcass cord end point is higher than the height of the outer end point of the bead chafer, adds a layer of fiber cord outside the bead and apex rubber, improves the bead strength, and makes the rigidity transition uniform. There are problems in actual use. First, from the design point of view, ① the structure in which the height of the carcass cord is higher than the height of the outer end point of the bead chafer will cause the carcass cord end point to be stressed, resulting in cracks at the carcass cord end point and cracks outside the bead; ② the outer height of the fiber cord is higher than the height of the carcass cord. If the height of the fiber cord is set too low, it will cause material accumulation and easily cause air pockets; If the height of the fiber cord is set too high, it is close to the horizontal axis. The area near the horizontal axis is the area where the tire deforms the most. Due to repeated bending and deformation during tire operation, the fiber cord ends are easily damaged, resulting in cracks outside the tire bead. In addition, the fiber cord does not wrap the tire body ends, and cannot effectively protect the tire body cord ends. Cracks are likely to occur at the tire body cord ends, resulting in cracks outside the tire bead. Second, from a manufacturing perspective, this setting of adding a layer of fiber cord outside the tire bead and apex will increase the complexity of the molding process, increase the number of steps, and affect production efficiency.)

[0004] 2. Chinese invention patent CN103738122A discloses a full steel radial tire with internal reinforcement in the bead and its preparation method, which specifically includes a steel cord turn-up layer and a steel cord reinforcement layer on both sides of the carcass cord layer, the steel cord turn-up layer is laminated between the carcass cord layer and the inner liner layer; the steel cord reinforcement layer is arranged between the carcass cord layer and the apex rubber on the inner side of the bead. That is, by adding a layer of bead chafer between the carcass and the apex rubber, the overall strength of the bead is improved, thereby improving the high-load resistance and durability of the tire. (This method of improving the durability of the tire bead by adding a layer of steel cord between the tire body and the apex rubber is very limited in actual application, and there are two main bottlenecks. First, from a design perspective, the overall stability of the tire bead is destroyed, which will lead to uneven force on the tire bead, poor overall stability of the tire bead, cracks at the end of the tire body cord, and cracks outside the tire bead; the ratio of the steel wire to the rubber modulus in the tire bead is usually 500 times, and the material is large and the force is complex. When the rolling direction is changed under a high-load environment of the tire, it is easy to cause stress concentration, resulting in damage to the upper / lower end of the steel cord reinforcement layer, and the extension leads to damage to the inside / outside of the steel cord anti-wrapping layer, and cracks outside the tire bead and inside the tire bead. The reinforcement method of adding only new steel wire materials cannot effectively solve the problems related to poor tire bead stability of all-steel radial tires. Second, from a manufacturing perspective, this setting of adding a layer of steel cord between the tire body cord and the apex rubber will increase the complexity of the molding process, increase the sequence, and affect the efficiency of production.)

[0005] However, both of the above-mentioned improvement methods only improve the bead stiffness by means of a single factor, without taking into account the overall stability of the bead area; in view of this, the present invention proposes an all-steel load-bearing radial tire that can improve the durability of the bead. Summary of the invention

[0006] The purpose of the present invention is to provide an all-steel load-bearing radial tire to solve the problems raised in the background technology.

[0007] In order to achieve the above object, the present invention adopts the following technical solutions:

[0008] An all-steel load-bearing radial tire, comprising a global structure and an internal structure, wherein the global structure comprises a crown, a carcass, a sidewall and a bead; the sidewall is connected to the bead and the crown; the part of the carcass located inside the sidewall forms a filling space extending from the bead toward the crown, and the internal structure comprises a carcass cord, an integral reinforcing layer of the bead portion, an inner reinforcing layer of the bead wrapper, a bead wrapper, a soft apex, a hard apex and a wire ring, wherein the hard apex and the soft apex are self- The tire is connected to the upper end of the tire bead from bottom to top, and the wire ring is arranged inside the tire bead; the carcass cord covers the outside of the hard apex and the soft apex, and the chafer is wrapped around the outside of the carcass cord, and the carcass cord and the chafer form a curved reverse wrapping on the outside of the carcass; the tire bead integral reinforcement layer is arranged between the carcass cord, the soft apex, the hard apex and the wire ring, and the inner reinforcement layer of the chafer is arranged between the carcass cord and the inner end point of the chafer;

[0009] The section width of the tire profile is recorded as SW, the lower side plate height is recorded as LSH, and the bead positioning line width is recorded as TTZ;

[0010] The height of the end point of the carcass cord in the vertical direction is recorded as HSC, the height of the inner end point of the integral reinforcement layer of the bead portion in the vertical direction is recorded as H3N.I, the height of the outer end point of the integral reinforcement layer of the bead portion in the vertical direction is recorded as L3N.I, the height of the upper end point of the inner reinforcement layer of the bead wrapper in the vertical direction is recorded as H4N.I, the height of the lower end point of the inner reinforcement layer of the bead wrapper in the vertical direction is recorded as L4N.I, the height of the outer end point of the bead wrapper in the vertical direction is recorded as HWC.O, the height of the inner end point of the bead wrapper in the vertical direction is recorded as HWC.I, and the height of the upper end point of the hard apex rubber in the vertical direction is recorded as HHBF.

[0011] Preferably, the relationship between the lower side plate height LSH and the cross-sectional width SW is: 0.500≤LSH / SW≤0.549; the relationship between the bead portion positioning line width TTZ and the cross-sectional width SW is: 0.140≤TTZ / SW≤0.156.

[0012] Preferably, the relationship between the carcass cord end point height HSC and the lower side plate height LSH is: 0.365≤HSC / LSH≤1.056.

[0013] Preferably, the relationship between the outer endpoint height HWC.O of the bead chafer and the endpoint height HSC of the carcass cord is: 0.79≤HWC.O / HSC≤1.39; the relationship between the inner endpoint height HWC.I of the bead chafer and the endpoint height HSC of the carcass cord is: 1.26≤HWC.I / HSC≤1.67.

[0014] Preferably, the relationship between the upper endpoint height HHBF of the hard apex and the endpoint height HSC of the carcass cord is: 1.00≤HHBF / HSC≤1.67.

[0015] Preferably, the tire bead integral reinforcement layer wraps the end points of the carcass cord, and the material of the tire bead integral reinforcement layer has a breaking strength of ≥215.6N, an adhesive strength of ≥137.2 (N / 10mm), a rubber coating strength M100 of 2.5Mpa≤M100≤4.3Mpa, and a modulus E * Meet 5.1Mpa≤E * ≤10.1Mpa;

[0016] The inner end point height H3N.I of the overall reinforcement layer of the bead portion is 20 to 40 mm higher than the upper end point HHBF of the hard apex rubber; the outer end point height L3N.I of the overall reinforcement layer of the bead portion is 10 to 20 mm lower than the end point HSC of the carcass cord; the thickness of the overall reinforcement layer of the bead portion is 0.5 mm to 5 mm.

[0017] Preferably, the bead portion integral reinforcement layer is compounded on the carcass cord, and its shape is designed to be wide at the top and narrow at the bottom.

[0018] Preferably, the material of the inner reinforcing layer of the chafer meets the requirements of breaking strength ≥ 215.6N, bonding strength ≥ 137.2 (N / 10mm), coating strength M100 meets the requirements of 2.5Mpa≤M100≤4.3Mpa, and modulus E * Meet 5.1Mpa≤E * ≤10.1Mpa;

[0019] The height H4N.I of the upper end point of the inner reinforcing layer of the chafer is 10 to 30 mm higher than the inner end point HWC.I of the chafer; the height L4N.I of the lower end point of the inner reinforcing layer of the chafer is 10 to 30 mm lower than the inner end point HWC.I of the chafer, and the thickness of the inner reinforcing layer of the chafer is 0.5 mm to 5 mm.

[0020] Preferably, the inner reinforcing layer of the chafer is compounded on the inner side of the chafer.

[0021] Preferably, the elongation at break Eb1 of the hard apex meets 185%≤Eb1≤295%; the elongation at break Eb2 of the soft apex meets 418%≤Eb1≤534%; and the modulus ratio between the hard apex and the soft apex meets 1.82≤E*hard / E*soft≤4.91.

[0022] Compared with the prior art, the present invention provides an all-steel load-bearing radial tire, which has the following beneficial effects:

[0023] The present invention proposes an all-steel load-bearing radial tire. Under the condition of ensuring other properties of the tire, the outer profile section width SW, the lower side plate height LSH, and the bead portion positioning line width TTZ of the tire are optimized. Under the constraints of the technical parameters given by the present invention, the stress deformation of the tire bead portion is small; at the same time, in terms of structural design, the carcass cord end point height HSC, the bead chafer outer end point height HWC.O, the bead chafer inner end point height HWC.I, the hard apex upper end point height HHBF are set on the carcass cord, apex and The overall reinforcement layer of the bead part between the wire rings, as well as the inner reinforcement layer of the bead wrapper arranged between the carcass cord and the inner end point of the bead wrapper are optimized, and new requirements are put forward for the strength of the reinforcement layer and the strength and modulus of the cord covering rubber; the deformation and modulus matching of soft and hard apex rubbers are also deeply explored and verified in the formula materials, so that the stress deformation of the entire bead area is reduced, thereby reducing the early cracks at the carcass cord end point, the outer / inner end point of the bead wrapper, the upper end point of the hard apex rubber, and the widest position of the wire ring, thereby effectively extending the service life of the tire. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 It is a partial cross-sectional view in the meridian direction of the existing normal tire mentioned in Example 1 of the present invention;

[0025] Figure 2 A partial cross-sectional view of the all-steel load-bearing radial tire in the meridian direction mentioned in Example 1 of the present invention;

[0026] Figure 3 This is a diagram for laying out the carcass cord and the chafer mentioned in Example 1 of the present invention.

[0027] Description of the numbers in the figure:

[0028] 1. Carcass cord; 2. Overall reinforcement layer of the bead; 3. Inner reinforcement layer of the bead chafer; 4. Bead chafer; 5. Soft apex rubber; 6. Hard apex rubber; 7. Wire ring. DETAILED DESCRIPTION

[0029] The technical solutions in the embodiments of the present invention will be described clearly and completely below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments.

[0030] The present invention aims at the problems existing in the existing structure, analyzes the profile and structure of the tire bead in detail, and after cutting the section of the faulty tire, it is found that the starting position of the tire bead damage is mainly ① the end point of the carcass cord, ② the outer end point of the bead chafer, ③ the inner end point of the bead chafer, ④ the upper end point of the hard apex rubber, and ⑤ the widest part of the wire ring. The present invention takes the above problems into consideration and provides a new all-steel load-bearing radial tire structure with high tire bead durability. A preferred embodiment of the present invention is described in detail below in conjunction with the accompanying drawings, which specifically includes the following contents.

[0031] Embodiment 1:

[0032] See also Figure 2 , Figure 2 The cross-sectional view in the meridian direction of the all-steel load-bearing radial tire structure proposed in the present invention is shown, and its outer contour design includes the section width SW, the lower side plate height LSH, and the bead portion positioning line width TTZ; the internal structure includes a carcass cord 1, a bead portion integral reinforcement layer 2 arranged between the carcass cord 1, a soft apex 5, a hard apex 6 and a steel bead 7, a bead bead inner reinforcement layer 3 arranged between the carcass cord 1 and the inner end point of the bead chafer 4, a bead chafer 4, a soft apex 5, a hard apex 6, and a steel bead 7; the height of the end point of the carcass cord 1 in the vertical direction The height of the inner end point of the overall reinforcement layer 2 of the bead portion in the vertical direction is H3N.I, the height of the outer end point of the overall reinforcement layer 2 of the bead portion in the vertical direction is L3N.I, the height of the upper end point of the inner reinforcement layer 3 of the bead wrapper in the vertical direction is H4N.I, the height of the lower end point of the inner reinforcement layer 3 of the bead wrapper in the vertical direction is L4N.I, the height of the outer end point of the bead wrapper 4 in the vertical direction is HWC.O, the height of the inner end point of the bead wrapper 4 in the vertical direction is HWC.I, and the height of the upper end point of the hard apex rubber 6 in the vertical direction is HHBF.

[0033] The relationship between the lower side plate height LSH of the outer contour of the tire structure and the tire cross-sectional width SW is 0.500≤LSH / SW≤0.549, preferably 0.535; when LSH / SW is set too small, that is, the tire horizontal axis height LSH is set too small, the tire deformation area moves downward, and the stress and deformation of each cord end point in the bead area increases, resulting in an increased risk of bead failure; when LSH / SW is set too large, that is, the tire horizontal axis height LSH is set too large, the tire deformation area moves upward, although it is beneficial to the stress and deformation of the bead area, it causes the crown of the tire to be stressed and the shear strain of the belt layer to increase, resulting in an increased risk of crown failure.

[0034] The relationship between the outer contour bead positioning line width TTZ of the tire structure and the tire section width SW is 0.140≤TTZ / SW≤0.156, preferably 0.151; when TTZ / SW is set too small, that is, the bead width TTZ is set too small, the bead stiffness is insufficient, and the stress and deformation of each end point of the bead part increases, resulting in an increased risk of failure of each cord end point of the bead part; when TTZ / SW is set too large, that is, the bead width TTZ is set too large, although the bead stiffness can be increased, the vulcanization time will be increased, the risk of over-vulcanization of the crown portion will be increased, and the durability of the crown portion will be reduced; at the same time, it will cause a decrease in production efficiency and an increase in cost.

[0035] The relationship between the carcass cord endpoint height HSC and the outer contour lower side plate height LSH of the tire structure is 0.365≤HSC / LSH≤1.056, and the preferred HSC / LSH is 0.365; when HSC / LSH is set too large, that is, the carcass cord endpoint height HSC is set too high, the carcass cord endpoint height is close to the horizontal axis, and the area near the horizontal axis is the largest deformation area of ​​the tire, which will increase the risk of carcass cord endpoint cracking; when HSC / LSH is set too small, that is, the carcass cord endpoint height HSC is set too small, it will directly reduce the rigidity of the bead area, and the bead durability will be significantly reduced, so the carcass cord endpoint height has a reasonable height range, within this range, the tire bead durability can be guaranteed.

[0036] The relationship between the outer end point height HWC.O of the bead wrapper and the end point height HSC of the carcass cord of the tire structure is 0.79≤HWC.O / HSC≤1.39, and the preferred HWC.O / HSC is 1.15; when HWC.O / HSC is set too large, that is, the outer end point height HWC.O of the bead wrapper is set too high, although the end point of the carcass cord can be protected more effectively, the difference between the outer end point height of the bead wrapper and the end point height of the carcass cord is too large, which will cause stress concentration on the outer end point of the bead wrapper, resulting in an increased risk of cracking at the outer end point of the bead wrapper; when HWC.O / HSC is set too small, that is, the outer end point height HWC.O of the bead wrapper is set too small, it cannot effectively protect the end point of the carcass cord, which will directly reduce the rigidity of the bead area, and the durability of the bead will be significantly reduced. Therefore, the outer end point height of the bead wrapper has a reasonable height range, and within this range, the durability of the tire bead can be guaranteed.

[0037] The relationship between the inner end point height HWC.I of the bead chafer of the tire structure and the end point height HSC of the carcass cord is 1.26≤HWC.I / HSC≤1.67, and the preferred HWC.I / HSC is 1.67; when HWC.I / HSC is set too large, that is, the inner end point height HWC.I of the bead chafer is set too high, the inner end point height of the bead chafer is close to the horizontal axis, and the area near the horizontal axis is the area with the maximum deformation of the tire, which will increase the risk of cracking of the inner end point of the bead chafer; when HWC.I / HSC is set too small, that is, the inner end point height HWC.I of the bead chafer is set too small, the rigidity of the bead area will be directly reduced, and the durability of the bead will be significantly reduced, so the inner end point height of the bead chafer has a reasonable height range, within which the durability of the tire bead can be guaranteed and the risk of internal cracking is also low;

[0038] The relationship between the upper end point height HHBF of the hard apex of the tire structure and the end point height HSC of the carcass cord is 1.344≤HHBF / HSC≤1.67, and the preferred HHBF / HSC is 1.67; when the upper end point height of the hard apex exceeds the above range, its upper end point is close to the horizontal axis deformation area, which easily causes the hard apex and the carcass cord to delaminate during the operation of the tire; when the upper end point height of the hard apex is lower than the above range, its upper end point height is set too low, which will reduce the overall rigidity of the bead area and the durability of the bead will be reduced;

[0039] The tire structure is provided with an integral reinforcing layer 2 for the bead portion, which is located between the carcass cord 1, the hard apex rubber 6 and the wire ring 7. The main purpose of the setting is to solve: ① the gap between the carcass cord and the hard apex rubber causes the apex rubber to be empty; ② the bead cut burst caused by repeated shearing between the carcass cord and the wire ring; ③ the carcass cord end point cracks caused by repeated deformation of the carcass cord end point. The material of the integral reinforcing layer 2 for the bead portion needs to consider the comprehensive performance of adhesion, fatigue, aging, strength and modulus, and nylon 66 is preferred, with a fineness of 1260D; the breaking strength (N) of the cord meets ≥215.6, and the bonding strength (N / 10mm) is ≥137.2; the rubber coating strength M100 (Mpa) of the integral reinforcing layer 2 for the bead portion meets 2.5≤M100≤4.3, preferably M100 (Mpa) = 2.7; the modulus E * (Mpa)Satisfy 5.1≤E * ≤10.1, preferably E *(Mpa)=5.3; the height of the inner end point of the integral reinforcing layer 2 of the bead portion needs to be 10-30mm higher than the upper end point of the hard apex rubber 6; when it exceeds the above range, the end point is set too high and close to the horizontal axis deformation area, which may easily cause the integral reinforcing layer 2 of the bead portion to become empty during the operation of the tire; when it is less than the above range, the end point is set too low and close to the upper end point of the hard apex rubber 6, which may also easily cause air pockets; the height of the outer end point of the integral reinforcing layer 2 of the bead portion needs to be 10-20mm lower than the end point of the carcass cord 1; when it exceeds the above range, the width of the integral reinforcing layer 2 of the bead portion is too long, resulting in excessive accumulation of material under the bead portion; when it is less than the above range, the height of the outer end point of the integral reinforcing layer 2 of the bead portion is set too high, and the width of the integral reinforcing layer 2 of the bead portion is too small to fully protect the end point of the carcass cord 1.

[0040] The tire structure has a chafer inner reinforcement layer 3 disposed between the carcass cord 1 and the inner end point of the chafer 4. The purpose of the chafer inner reinforcement layer 3 is mainly to solve the problem of the inner end point of the bead being cracked due to shearing between the inner end point of the chafer 4 and the carcass cord 1. The material of the chafer inner reinforcement layer 3 needs to consider the comprehensive performance of adhesion, fatigue, aging, strength and modulus. Nylon 66 is preferred, and its fineness is 1260D; the breaking strength (N) of the cord meets ≥215.6, and the adhesion strength (N / 10mm) is ≥137.2; the rubber coating strength M100 (Mpa) of the overall reinforcement layer 3 of the bead portion meets 2.5≤M100≤4.3, preferably M100 (Mpa) = 2.7; the modulus E * (Mpa)Satisfy 5.1≤E * ≤10.1, preferably E * (Mpa)=5.3; the height of the upper end point of the inner reinforcing layer 3 of the bead wrapper needs to be 10-30mm higher than the inner end point of the bead wrapper 4; when it exceeds the above range, the end point is set too high and close to the horizontal axis deformation area, which may easily cause the inner reinforcing layer 3 of the bead wrapper to be emptied during the operation of the tire; when it is less than the above range, the end point is set too low and is close to the inner end point of the bead wrapper 4, and cannot play the role of protecting the inner end point of the bead wrapper 4; the height of the lower end point of the inner reinforcing layer 3 of the bead wrapper needs to be 10-30mm lower than the inner end point of the bead wrapper 4. When it exceeds the above range, the height of the lower end point of the inner reinforcing layer 3 of the bead wrapper is set too high, that is, the width of the inner reinforcing layer 3 of the bead wrapper is too long, resulting in excessive accumulation of material in the bead portion; when it is less than the above range, the width of the inner reinforcing layer 3 of the bead wrapper is too small, and is close to the inner end point of the bead wrapper 4, and cannot play the role of protecting the inner end point of the bead wrapper 4.

[0041] The elongation of the hard apex 6 and soft apex 5 formulas of the tire structure is optimized, where the Eb (%) of the hard apex 6 needs to meet 185 ≤ Eb (%) ≤ 295, preferably Eb (%) = 207; the Eb (%) of the soft apex 5 needs to meet 418 ≤ Eb (%) ≤ 534, preferably Eb (%) = 457. (Here Eb (%) represents the elongation ratio of the rubber when it is torn off). And the modulus ratio between the two is considered to meet 1.82 ≤ E * Hard / E * Soft ≤ 4.91 ratio, preferably E * Hard / E * The soft one is 2.31; the soft and hard apex rubbers use the formula with optimized elongation to effectively reduce the repeated deformation of the tire bead during driving, which leads to the tearing of the soft and hard apex rubbers and the failure of the bead being empty; in addition, the modulus matching between the soft and hard apex rubbers needs to be within a reasonable range. * Hard / E * When the softness exceeds the above range, and the ratio of the modulus of the hard apex 6 to the soft apex 5 is too large, the material rigidity distribution of the bead part will be uneven, which is not good for the durability of the bead. * Hard / E * When the softness is smaller than the above range, that is, the hard apex rubber 6 modulus is low, the material rigidity of the bead part is insufficient, which will also affect the durability of the tire bead.

[0042] See also Figure 3 , Figure 3 The diagram of laying the carcass cord and the chafer of the present invention is shown, wherein the integral reinforcing layer 2 of the bead portion is compounded on the carcass cord 1, and its size is wide at the top and narrow at the bottom; the inner reinforcing layer 3 of the chafer is compounded on the inner and upper side of the chafer 4.

[0043] In order to prove the technical effect of the technical solution adopted by the present invention, this embodiment and comparative example were verified and compared. The specific contents are as follows.

[0044] Comparative Examples 1 to 4:

[0045] When LSH / SW values ​​are 0.500, 0.528, 0.542, and 0.549, respectively, the change in the tire section width from the initial state to the loaded state is greater, the greater the deformation of the tire, and the greater the risk of tire bead failure.

[0046]

[0047] Comparative Examples 5 and 6:

[0048] When the TTZ / SW values ​​are 0.140 and 0.156, the higher the test result data of machine tool 1, the better the tire bead durability performance.

[0049]

[0050] Comparative Example 7:

[0051] When the HSC / LSH value is 1.056, the higher the test result data of machine tool 1, the better the tire bead durability performance.

[0052]

[0053] Comparative Examples 8 and 9:

[0054] When the HWC.O / HSC values ​​are 0.79 and 1.39, the higher the test result data of machine tool 1, the better the tire bead durability performance.

[0055]

[0056] Comparative Examples 10 and 11:

[0057] When the HWC.I / HSC value is 1.26 or 1.51, the shear strain between the inner end point of the chafer and the carcass is larger, the stress deformation is greater, and the risk of cracks in the bead is greater; the higher the test result data of machine tool 1, the better the durability of the tire bead.

[0058]

[0059] Comparative Examples 12 and 13:

[0060] When the HHBF / HSC values ​​are 1.00 and 1.34, the higher the test result data of machine tool 2, the better the tire bead durability performance.

[0061]

[0062] Comparative Examples 14 and 15:

[0063] When there is no integral reinforcement layer for the bead portion and the integral reinforcement layer for the bead portion is a film, the greater the shear strain, the greater the stress deformation of the bead portion.

[0064]

[0065] Comparative Examples 16 and 17:

[0066] When there is no inner reinforcing layer of the chafer and the inner reinforcing layer of the chafer is a film, the greater the shear strain, the greater the stress deformation at the inner end point of the bead.

[0067]

[0068] Comparative Example 18:

[0069] When the soft apex Eb (%) = 493 and the hard apex Eb (%) = 295, the test results of machine tool 2 show that the higher the data, the better the tire bead durability performance.

[0070]

[0071] Comparative Example 19:

[0072] E * Hard / E * When the soft value is 4.91, the experimental results of machine tool 2 show that the higher the data, the better the durability performance of the tire bead.

[0073]

[0074] The above description is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes according to the technical scheme and inventive concept of the present invention within the technical scope disclosed by the present invention, which should be covered by the protection scope of the present invention.

Claims

1. An all-steel load-bearing radial tire, comprising a global structure and an internal structure, wherein the global structure comprises a crown, a carcass, a sidewall and a bead; the sidewall is connected to the bead and the crown; the part of the carcass located inside the sidewall forms a filling space extending from the bead toward the crown, characterized in that: The internal structure comprises a carcass cord (1), an integral reinforcing layer of the bead portion (2), an inner reinforcing layer of the bead chafer (3), a bead chafer (4), a soft apex rubber (5), a hard apex rubber (6) and a wire ring (7), wherein the hard apex rubber (6) and the soft apex rubber (5) are sequentially connected to the upper end of the bead from bottom to top, and the wire ring (7) is arranged inside the bead; the carcass cord (1) covers the hard apex rubber (6) and the soft apex rubber (5). ), the bead chafer (4) is coated on the outside of the carcass cord (1), and the carcass cord (1) and the bead chafer (4) form a curved reverse coating on the outside of the carcass; the bead portion integral reinforcement layer (2) is arranged between the carcass cord (1), the soft apex (5), the hard apex (6) and the wire ring (7), and the bead chafer inner reinforcement layer (3) is arranged between the carcass cord (1) and the inner end point of the bead chafer (4); The section width of the tire profile is recorded as SW, the lower side plate height is recorded as LSH, and the bead positioning line width is recorded as TTZ; The height of the end point of the carcass cord (1) in the vertical direction is recorded as HSC, the height of the inner end point of the bead portion integral reinforcement layer (2) in the vertical direction is recorded as H3N.I, the height of the outer end point of the bead portion integral reinforcement layer (2) in the vertical direction is recorded as L3N.I, the height of the upper end point of the inner reinforcement layer (3) of the bead chafer in the vertical direction is recorded as H4N.I, the height of the lower end point of the inner reinforcement layer (3) of the bead chafer in the vertical direction is recorded as L4N.I, the height of the outer end point of the bead chafer (4) in the vertical direction is recorded as HWC.O, the height of the inner end point of the bead chafer (4) in the vertical direction is recorded as HWC.I, and the height of the upper end point of the hard apex (6) in the vertical direction is recorded as HHBF.

2. The all-steel load-bearing radial tire according to claim 1, characterized in that: The relationship between the lower side plate height LSH and the section width SW is: 0.500≤LSH / SW≤0.549; the relationship between the tire bead positioning line width TTZ and the section width SW is: 0.140≤TTZ / SW≤0.

156.

3. The all-steel load-bearing radial tire according to claim 1, characterized in that: The relationship between the carcass cord end point height HSC and the lower side plate height LSH is: 0.365≤HSC / LSH≤1.

056.

4. The all-steel load-bearing radial tire according to claim 1, characterized in that: The relationship between the outer end point height HWC.O of the bead chafer and the end point height HSC of the carcass cord is: 0.79≤HWC.O / HSC≤1.39; the relationship between the inner end point height HWC.I of the bead chafer and the end point height HSC of the carcass cord is: 1.26≤HWC.I / HSC≤1.

67.

5. The all-steel load-bearing radial tire according to claim 1, characterized in that: The relationship between the upper end point height HHBF of the hard apex rubber and the end point height HSC of the carcass cord is: 1.00≤HHBF / HSC≤1.

67.

6. The all-steel load-bearing radial tire according to claim 1, characterized in that: The tire bead integral reinforcement layer (2) wraps the end points of the carcass cord (1), and the material of the tire bead integral reinforcement layer (2) has a breaking strength of ≥215.6N, an adhesive strength of ≥137.2 (N / 10mm), a coating strength M100 of 2.5Mpa≤M100≤4.3Mpa, and a modulus E * Meet 5.1Mpa≤E * ≤10.1Mpa; The inner end point height H3N.I of the overall reinforcement layer of the bead portion is 20 to 40 mm higher than the upper end point HHBF of the hard apex rubber; the outer end point height L3N.I of the overall reinforcement layer of the bead portion is 10 to 20 mm lower than the end point HSC of the carcass cord; the thickness of the overall reinforcement layer of the bead portion is 0.5 mm to 5 mm.

7. The all-steel load-bearing radial tire according to claim 6, characterized in that: The tire bead integral reinforcement layer (2) is compounded on the carcass cord (1), and its shape is designed to be wide at the top and narrow at the bottom.

8. The all-steel load-bearing radial tire according to claim 1, characterized in that: The material of the inner reinforcing layer (3) of the tire chafer has a breaking strength of ≥215.6N, an adhesive strength of ≥137.2 (N / 10mm), a coating strength M100 of 2.5Mpa≤M100≤4.3Mpa, and a modulus E * Meet 5.1Mpa≤E * ≤10.1Mpa; The height H4N.I of the upper end point of the inner reinforcing layer of the chafer is 10 to 30 mm higher than the inner end point HWC.I of the chafer; the height L4N.I of the lower end point of the inner reinforcing layer of the chafer is 10 to 30 mm lower than the inner end point HWC.I of the chafer, and the thickness of the inner reinforcing layer of the chafer is 0.5 mm to 5 mm.

9. The all-steel load-bearing radial tire according to claim 8, characterized in that: The chafer inner side reinforcing layer (3) is compounded on the inner side and upper side of the chafer (4).

10. The all-steel load-bearing radial tire according to claim 1, characterized in that: The elongation at break Eb1 of the hard apex (6) satisfies 185%≤Eb1≤295%; the elongation at break Eb2 of the soft apex (5) satisfies 418%≤Eb1≤534%; the modulus ratio between the hard apex (6) and the soft apex (5) satisfies 1.82≤E*hard / E*soft≤4.91.

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