Nested part adapted to end point of belt ply and forming process thereof in tire production

Abstract

The invention discloses a nesting component matched with a belted layer end point and a forming process of the nesting component in tire production, and relates to the technical field of tires. According to the invention, the nesting component is adopted to replace edge covering rubber, rubber sheets and molding rubber in a four-layer belted layer structure, on one hand, endpoint damage caused by modulus difference of steel wires and rubber at the endpoints of the belted layers is reduced, so that the durability of the product is further improved, the service life of the tire is prolonged, and the utilization efficiency of materials is improved; on the other hand, the process complexity is reduced, the process flow is reduced, the edge covering rubber, film pasting and belted interlayer type rubber process is optimized to be achieved in one process, pasting operation is conducted in the forming process, and the production efficiency is improved; and meanwhile, the number of equipment is reduced, factory investment is reduced, and space utilization efficiency is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of tires, and particularly to a nested component adapted to the belt layer end point and its forming process in tire production. Background Art

[0002] In the field of tire manufacturing, TBR (all-steel radial tire) is widely used in trucks and buses due to its excellent wear resistance, handling performance and safety. At present, the commonly used structures of TBR mainly include 3+0 belt layer structure and 4-layer belt layer structure, and each structure has its unique composition and process requirements. The modulus difference between the steel wire and the rubber at the belt layer end point is one of the main reasons for the end point damage. At present, the design and production adopt the form of belt layer edge wrapping rubber + film to adjust the transition of the modulus difference and the flatness of the belt layer.

[0003] (1) 3+0 belt layer structure

[0004] The 3+0 belt layer structure is a relatively common design in TBR, and its composition is as follows:

[0005] No. 2 belt layer edge wrapping rubber: This kind of rubber material is used to wrap the edge of the belt layer, playing a role in protecting the belt layer and enhancing the overall structure of the tire;

[0006] No. 2 belt layer: As the main belt layer, it provides the strength and stability of the tire.

[0007] Film is pasted on the upper and lower sides according to actual needs: According to the specific use requirements and performance requirements of the tire, film is pasted on the upper and lower sides of the No. 2 belt layer to further optimize the flatness of the No. 2 belt layer and the stability of the end point.

[0008] Process characteristics: The edge wrapping rubber and the film are pre-prepared. The edge wrapping rubber and the film pasted on the upper and lower sides need to be completed in the previous process of tire manufacturing, which requires precise control of the rubber material formula, thickness and size. Compared with the 4-layer belt layer structure, the No. 2 belt layer does not require the shaping rubber below, but requires the 0° belt layer to carry out crown binding to reduce the strain of the shoulder under heavy load conditions.

[0009] (2) 4-layer belt layer structure

[0010] The 4-layer belt layer structure has been used in an increasing proportion in recent years under the market demand for high speed and high wear resistance. Due to its structural characteristics, the ground contact imprint of the product is better, and it has better wear life under the condition that other design elements are the same. Its composition is as follows:

[0011] No. 2 belt layer edge wrapping rubber: Also used to wrap the edge of the belt layer to protect the belt layer;

[0012] Tape: Based on the 2# belt layer, edge - wrapping rubber or tape is used to ensure the stability of the belt layer endpoints.

[0013] Inter - layer rubber between 2# and 3# belt layers: Special inter - layer rubber is added between the 2# belt layer and the 3# belt layer to ensure the flatness of the 2# belt layer, assist in the modulus transition at the endpoints of the 2# belt layer, and reduce the failure of the endpoints of the 2# belt layer.

[0014] Process characteristics: High requirements for the previous processes. The edge - wrapping rubber, tape, and inter - layer rubber all need to be completed in the previous processes, with relatively high requirements for the preparation of rubber compounds and the extrusion and lamination processes. Due to the involvement of multiple belt layers and the lamination of multiple rubber compounds, the process of the 4 - layer belt layer structure is more complex, with higher requirements for production equipment and process flow. It may affect production efficiency during the production process and requires more stringent quality control and production management.

[0015] In summary, whether it is the 3 + 0 belt layer structure or the 4 - layer belt layer structure, the current designs of edge - wrapping rubber, tape, and inter - layer rubber have the problem of needing to be completed in the previous processes, so they need to be optimized. Summary of the Invention

[0016] The technical problem to be solved by the present invention is: Overcoming the deficiencies of the prior art, providing a nested component adapted to the endpoints of the belt layer and its forming process in tire production. Using the nested component to replace the edge - wrapping rubber, tape, and inter - layer rubber in the four - layer belt layer structure, while reducing the endpoint damage caused by the modulus difference between the steel wire and rubber at the belt layer endpoints, reducing the process complexity, reducing the process flow, and improving production efficiency and space utilization efficiency.

[0017] The technical solution of the present invention is as follows:

[0018] On the one hand, the present invention provides a nested component adapted to the endpoints of the belt layer. The nested component is C - shaped and the width of the upper end face is greater than the width of the lower end face. When the tire belt layer is a 0° belt layer, 1# belt layer, 2# belt layer, and 3# belt layer structure, the nested component wraps around the endpoints of the 1# belt layer and the 2# belt layer. The upper end face of the nested component of the 1# belt layer extends beyond the endpoint of the 3# belt layer. The upper end face of the nested component of the 2# belt layer extends beyond the inner endpoint of the 0° belt layer but does not extend beyond the endpoint of the 3# belt layer, and the lower end face of the nested component of the 2# belt layer extends beyond the endpoint of the 1# belt layer. When the tire belt layer is a 1# belt layer, 2# belt layer, 3# belt layer, and 4# belt layer structure, the nested component wraps around the endpoints of the 1# belt layer, 2# belt layer, and 3# belt layer. The upper and lower end faces of the nested component of the 2# belt layer extend beyond the endpoints of the 3# belt layer and the 1# belt layer respectively.

[0019] Preferably, the two ends and the inner side of the corners of the nested component are all rounded.

[0020] Preferably, the thickness of the upper and lower end faces of the nested component gradually decreases from the corner to the end point.

[0021] Preferably, the width difference between the upper and lower end faces of the nested component is 10 - 25 mm.

[0022] Preferably, the width of the upper end face of the nested component is 47 mm, and the width of the lower end face is 22 mm.

[0023] Preferably, the upper end face of the nested component inclines upward by 3° - 5°, and the lower end face inclines downward by 2° - 3°.

[0024] Preferably, the nested component comprises the following components in parts by weight: 100 parts of natural rubber, 60 - 62 parts of carbon black, 8 parts of zinc oxide, 2 parts of tackifying resin, 0.5 part of adhesion promoter, 7.5 - 8 parts of antioxidant, 5 - 5.5 parts of methylene donor adhesive, 1.5 - 2.2 parts of resorcinol adhesive, and 1.3 parts of vulcanization accelerator.

[0025] Preferably, the carbon black is N326; the tackifying resin is SP1068; the adhesion promoter is cobalt caprylate; the antioxidant comprises 2 parts of 6PPD and 5.5 - 6 parts of HODT20; the methylene donor adhesive is at least one of RA - 65, HMMM, and HMT; the resorcinol adhesive is at least one of B - 20 - S, SL3020, and R - 80; the vulcanization accelerator is DZ.

[0026] On the other hand, the present invention provides a forming process of the above - mentioned nested component adapted to the end points of the belt layer in tire production, comprising the following steps:

[0027] S1: Absorb the belt layer to which the nested component needs to be adhered by using a belt layer adsorption structure;

[0028] S2: Use a left - right combined pressing and feeding mechanism to send the nested component to both ends of the belt layer and nest it at both ends of the belt layer;

[0029] S3: The forming drum rotates and fits;

[0030] S4: Roll the nested component from the end point of the belt layer inward through a rolling mechanism to complete the adhesion of the nested component on the belt layer;

[0031] S5: According to the above operations, sequentially adhere the nested components at both ends of the 1# belt layer and the 2# belt layer, or the nested components at both ends of the 1# belt layer, the 2# belt layer, and the 3# belt layer, and then form and adhere each belt layer in the order of the 0° belt layer, the 1# belt layer and the 2# belt layer, the 3# belt layer or the 1# belt layer, the 2# belt layer, the 3# belt layer, the 4# belt layer.

[0032] Preferably, in step S4, the rolling speed is 120±5 r / min, and the rolling pressure is 0.7±0.05 MPa.

[0033] Compared with the prior art, the present invention has the following beneficial effects:

[0034] The present invention uses nested components to replace the edge wrapping rubber, the film, and the shaped rubber in the four-layer belt structure. On the one hand, it reduces the endpoint damage caused by the modulus difference between the steel wire and the rubber at the endpoint of the belt layer, thereby further improving the durability of the product, increasing the tire life, and improving the material utilization efficiency. On the other hand, it reduces the process complexity, reduces the process flow, optimizes the edge wrapping rubber + film sticking + shaped rubber process between the belt layers into one process, and performs the sticking operation during the forming process, improving the production efficiency. At the same time, it reduces the number of equipment, bringing about a reduction in factory investment and an improvement in space utilization efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 is a schematic structural diagram of the nested component adapted to the endpoint of the belt layer of the present invention.

[0036] Figure 2 is a schematic structural diagram of the 3+0 belt layer structure provided with the nested component in the present invention.

[0037] Figure 3 is Figure 1 a partial enlarged view at A.

[0038] Figure 4 is a schematic forming process diagram of the nested component adapted to the endpoint of the belt layer in the tire production of the present invention.

[0039] Figure 5 is the difference between the crown arc growth and the 100 kPa tread radial expansion of the tire of Example 1 of the present invention after being inflated to the target air pressure.

[0040] Figure 6 is the difference between the crown arc growth and the 100 kPa tread radial expansion of the tire of Comparative Example 1 of the present invention after being inflated to the target air pressure.

[0041] Figure 7 is a comparison diagram of the difference between the crown arc growth and the 100 kPa tread radial expansion of the tires of Example 1 and Comparative Example 1 of the present invention after being inflated to the target air pressure.

[0042] Figure 8 is a comparison diagram of the crown arc profile shapes of the tires of Example 1 and Comparative Example 1 of the present invention after being inflated to 700 kPa.

[0043] Figure 9 is a comparison diagram of the crown arc profile shapes of the tires of Example 1 and Comparative Example 1 of the present invention after being inflated to 900 kPa.

[0044] Figure 10 It is the imprint analysis result of the tire in Embodiment 1 and Comparative Example 1 of the present invention under 900 kPa and 4.125 t.

[0045] Figure 11 It is the imprint analysis result of the tire in Embodiment 1 and Comparative Example 1 of the present invention under 900 kPa and 5.3 t.

[0046] Figure 12 It is the durability test result of the 1# belt layer in Embodiment 1 and Comparative Example 1 of the present invention.

[0047] Figure 13 It is the durability test result of the 2# belt layer in Embodiment 1 and Comparative Example 1 of the present invention.

[0048] Figure 14 It is the durability test result of the 0° belt layer in Embodiment 1 and Comparative Example 1 of the present invention.

[0049] Figure 15 It is the test result of the full - cycle amplitude of the maximum principal strain of the 1# belt layer, 2# belt layer, and 0° belt layer in Embodiment 1 and Comparative Example 1 of the present invention under 900 kPa air pressure and 4.125 T load.

[0050] Figure 16 It is the test result of the full - cycle amplitude of the maximum principal strain of the 1# belt layer, 2# belt layer, and 0° belt layer in Embodiment 1 and Comparative Example 1 of the present invention under 900 kPa air pressure and 5.3 T load.

[0051] Figure 17 It is the test result of the full - cycle amplitude of the end - point shear strain of the 1# belt layer, 2# belt layer, and 0° belt layer in Embodiment 1 and Comparative Example 1 of the present invention under 900 kPa air pressure and 4.125 T load.

[0052] Figure 18 It is the test result of the full - cycle amplitude of the end - point shear strain of the 1# belt layer, 2# belt layer, and 0° belt layer in Embodiment 1 and Comparative Example 1 of the present invention under 900 kPa air pressure and 5.3 T load.

[0053] In the figure, 1, nested component; 2, 0° belt layer; 3, 1# belt layer; 4, 2# belt layer; 5, 3# belt layer; 6, belt - layer adsorption structure; 7, combined pressure feeding mechanism; 8, rolling mechanism. Detailed implementation manners

[0054] In order to enable those skilled in the art to better understand the technical solutions in the present invention, the following will clearly and completely describe the technical solutions of the present invention in conjunction with the embodiments of the present invention.

[0055] AsFigure 1 As shown in the figure, the present invention provides a nested component adapted to the end points of the belt layer. The nested component 1 is C-shaped and the width of the upper end face is greater than that of the lower end face. When the tire belt layer has a structure of 0° belt layer 2, 1# belt layer 3, 2# belt layer 4, and 3# belt layer 5, the nested component 1 wraps around the end points of the 1# belt layer 3 and the 2# belt layer 4. Moreover, the upper end face of the nested component 1 of the 1# belt layer 3 extends beyond the end point of the 3# belt layer 5. The upper end face of the nested component 1 of the 2# belt layer 4 extends beyond the inner end point of the 0° belt layer 2 but does not extend beyond the end point of the 3# belt layer 5. And the lower end face of the nested component 1 of the 2# belt layer 4 extends beyond the end point of the 1# belt layer 3. When the tire belt layer has a structure of 1# belt layer 3, 2# belt layer 4, 3# belt layer 5, and 4# belt layer, the nested component 1 wraps around the end points of the 1# belt layer 3, the 2# belt layer 4, and the 3# belt layer 5. And the upper and lower end faces of the nested component 1 of the 2# belt layer 4 respectively extend beyond the end points of the 3# belt layer 5 and the 1# belt layer 3.

[0056] Example 1

[0057] As Figure 1 shown, for the nested component 1 adapted to the end points of the belt layer in this example, the width L1 of the upper end face is 47 mm, and the width L2 of the lower end face is 22 mm. The two ends of the nested component 1 are rounded to facilitate the extension of the rubber compound and reduce the thickness difference level at the end points. The inner side of the corner is also rounded to reduce the cavity area and reduce air entrapment. The upper end face of the nested component 1 is inclined upward by α = 3°, and the lower end face is inclined downward by β = 3°, which is beneficial to the discharge of air during the subsequent rolling process, reduces the generation of air entrapment, and after rolling, it adheres to the belt layer, forming a trend that the thickness of the upper and lower end faces of the nested component 1 gradually decreases from the corner to the end point, increasing the binding effect near the end point and reducing the strain at the end point. Among them, the belt layer structure in this example is the structure of 0° belt layer 2, 1# belt layer 3, 2# belt layer 4, and 3# belt layer 5 as shown in Figures 2 - 3 and Table 1.

[0058] In this example, the nested component 1 includes the following components in parts by weight: 100 parts of NR, 61 parts of N326, 8 parts of zinc oxide, 2 parts of tackifying resin SP1068, 0.5 part of cobalt caprylate, 2 parts of antioxidant 6PPD, 5.8 parts of antioxidant HODT20, 5.2 parts of methylene donor adhesive HMMM, 1.8 parts of resorcinol adhesive SL3020, and 1.3 parts of DZ.

[0059] As Figure 4 shown, the forming process of the nested component 1 adapted to the end points of the belt layer in this example in tire production includes the following steps:

[0060] S1: Use the belt layer adsorption structure 6 to suck the belt layer to which the nested component 1 needs to be attached;

[0061] S2: Use the left - right combined pressing and feeding mechanism 7 to send the nested part 1 to both ends of the belt layer and nest it at both ends of the belt layer. The left - right combined pressing and feeding mechanism 7 includes upper and lower baffles and a vertical baffle, and is in a horizontally placed U - shape as a whole;

[0062] S3: The forming drum is bent and adhered;

[0063] S4: Roll the nested part 1 from the end point of the belt layer inward through the rolling mechanism 8. The rolling speed is 120 r / min, and the rolling pressure is 0.7 MPa to complete the adhesion of the nested part 1 on the belt layer;

[0064] S5: According to the above operations, the nested parts 1 at both ends of the 1# belt layer 3 and the 2# belt layer 4 are adhered in sequence. Subsequently, in the order of the 0° belt layer 2, the 1# belt layer 3, the 2# belt layer 4, and the 3# belt layer 5, each belt layer is formed and adhered.

[0065] Example 2

[0066] As Figure 1 shown, for the nested part 1 adapted to the end point of the belt layer in this embodiment, the width of the upper end face is 47 mm, and the width of the lower end face is 22 mm. The two ends of the nested part 1 are chamfered to facilitate the extension of the rubber compound and reduce the thickness difference level at the end points; the inner side of the corner is also chamfered to reduce the cavity area and reduce air entrapment. The upper end face of the nested part 1 is inclined upward by 4°, and the lower end face is inclined downward by 2°, which is conducive to the discharge of air during the subsequent rolling process, reducing the generation of air entrapment. After rolling, it is adhered to the belt layer, forming a trend that the thickness of the upper and lower end faces of the nested part 1 gradually decreases from the corner to the end point, increasing the binding effect near the end point and reducing the strain at the end point. Among them, the structure of the belt layer in this embodiment is the 0° belt layer 2, the 1# belt layer 3, the 2# belt layer 4, and the 3# belt layer 5 structures as shown in Figure 2 and Table 1.

[0067] In this embodiment, the nested part 1 includes the following components in parts by weight: 100 parts of NR, 60 parts of N326, 8 parts of zinc oxide, 2 parts of tackifying resin SP1068, 0.5 part of cobalt caprylate, 2 parts of antioxidant 6PPD, 5.5 parts of antioxidant HODT20, 5 parts of methylene donor adhesive HMT, 1.5 parts of resorcinol adhesive R - 80, and 1.3 parts of DZ.

[0068] As Figure 3 shown, the forming process of the nested part 1 adapted to the end point of the belt layer in this embodiment in tire production includes the following steps:

[0069] S1: Use the belt layer adsorption structure 6 to absorb the belt layer to which the nested part 1 needs to be adhered;

[0070] S2: Use the left - right combined pressure feeding mechanism 7 to send the nested component 1 to both ends of the belt layer and nest it at both ends of the belt layer;

[0071] S3: The forming drum rotates and fits;

[0072] S4: Use the rolling mechanism 8 to roll - press the nested component 1 from the end points of the belt layer inward. The rolling speed is 115 r / min and the rolling pressure is 0.65 MPa to complete the fitting of the nested component 1 on the belt layer;

[0073] S5: According to the above operations, fit the nested components 1 at both ends of the 1# belt layer 3 and the 2# belt layer 4 in sequence. Subsequently, in the order of the 0° belt layer 2, the 1# belt layer 3, the 2# belt layer 4, and the 3# belt layer 5, form and fit each belt layer.

[0074] Example 3

[0075] As Figure 1 shown, the nested component 1 adapted to the end points of the belt layer in this example has an upper - end - face width of 47 mm and a lower - end - face width of 22 mm. The two ends of the nested component 1 are chamfered to facilitate the extension of the rubber compound and reduce the thickness difference level at the end points; the inner side of the corner is also chamfered to reduce the cavity area and reduce air entrapment. The upper end - face of the nested component 1 is inclined upward by 5° and the lower end - face is inclined downward by 3°, which is conducive to the discharge of air during the subsequent rolling process, reducing air entrapment. After rolling, it fits on the belt layer, forming a trend that the thickness of the upper and lower end - faces of the nested component 1 gradually decreases from the corner to the end point, increasing the binding effect near the end point and reducing the strain at the end point. Among them, the belt - layer structure of this example is the 0° belt layer 2, the 1# belt layer 3, the 2# belt layer 4, and the 3# belt layer 5 structures as Figure 2 shown in and Table 1.

[0076] In this example, the nested component 1 includes the following components in parts by weight: 100 parts of NR, 62 parts of N326, 8 parts of zinc oxide, 2 parts of tackifying resin SP1068, 0.5 part of cobalt caprylate, 2 parts of antioxidant 6PPD, 6 parts of antioxidant HODT20, 5.5 parts of methylene - donor adhesive RA - 65, 2.2 parts of resorcinol adhesive B - 20 - S, and 1.3 parts of DZ.

[0077] As Figure 3 shown, the forming process of the nested component 1 adapted to the end points of the belt layer in tire production in this example includes the following steps:

[0078] S1: Use the belt - layer adsorption structure 6 to absorb the belt layer that needs to fit the nested component 1;

[0079] S2: Use the left - right combined pressure feeding mechanism 7 to send the nested component 1 to both ends of the belt layer and nest it at both ends of the belt layer;

[0080] S3: The forming drum rotates and bends for fitting.

[0081] S4: The nested component 1 is rolled and pressed inward from the end points of the belt layer by the rolling mechanism 8 at a rolling speed of 125 r / min and a rolling pressure of 0.75 MPa to complete the fitting of the nested component 1 on the belt layer.

[0082] S5: According to the above operations, the nested components 1 at both ends of the 1# belt layer 3 and the 2# belt layer 4 are sequentially and well-fitted. Subsequently, in the order of the 0° belt layer 2, the 1# belt layer 3, the 2# belt layer 4, and the 3# belt layer 5, each belt layer is formed and fitted.

[0083] Comparative Example 1

[0084] The difference from Example 1 is that in Comparative Example 1, a film is used instead of the nested component 1, and the belt layer structure and film parameters are shown in Table 1.

[0085] Table 1 Belt layer structures of Example 1 and Comparative Example 1

[0086]

[0087]

[0088] Tires of the 12.00R24 specification are produced using the structural designs of Example 1 and Comparative Example 1, and the performance of the tires is tested:

[0089] (1) Finite element analysis

[0090] The finite element models of the tires of Example 1 and Comparative Example 1 are set up, and the analysis process is carried out under a tire pressure of 900 kPa, a single-tire load of 4.125 t and a tire pressure of 900 kPa, a single-tire load of 5.3 t. The analysis models are shown in Table 2. It can be seen from Table 2 that when the end points of the 1# belt layer 3 and the 2# belt layer 4 are coated with a conventional film in Comparative Example 1, the modulus is 1.128 MPa, while when the end points of the 1# belt layer 3 and the 2# belt layer 4 are coated with the nested component 1 of Example 1, the modulus is 2.242 MPa. The level of the modulus indicates the ability of the material to resist elastic deformation under a stress state. A larger modulus means greater difficulty in deformation.

[0091] Table 2 Finite element analysis models of the tires of Example 1 and Comparative Example 2

[0092]

[0093] (2) Inflation deformation

[0094] The inflation deformation tests of the tires of Example 1 and Comparative Example 1 were carried out at normal temperature of 25 °C and two air pressures of 700 kPa (when the market uses the tire with insufficient air) and 900 kPa (standard pressure). The test results are shown in Table 3:

[0095] Table 3 Test results of inflation deformation of the tires of Example 1 and Comparative Example 1

[0096]

[0097] The results show that when the conventional film of Comparative Example 1 and the nested part 1 of Example 1 are used for coating, the changes in the outer diameter and cross-sectional width of the tire itself after inflation are consistent and the difference in the change amount is not large.

[0098] The difference between the crown arc growth and the 100 kPa tread radial expansion of the tire of Example 1 after inflation to the target air pressure is as Figure 5 shown. The difference between the crown arc growth and the 100 kPa tread radial expansion of the tire of Comparative Example 1 after inflation to the target air pressure is as Figure 6 shown. It can be seen from the figure that the inflation trends of the outer contours of Example 1 and Comparative Example 1 are consistent, the crown arcs all show synchronous growth, and the change amplitudes are close, which can ensure the basic performance of the tire.

[0099] The comparison chart of the difference between the crown arc growth and the 100 kPa tread radial expansion of the tires of Example 1 and Comparative Example 1 after inflation to the target air pressure is as Figure 7 shown. It can be seen from the figure that the inflation trends of the outer contours of Example 1 and Comparative Example 1 are consistent, but in terms of the growth at the shoulder part, the growth of Example 1 is greater, which shows that while ensuring the synchronous growth of the crown arc, the synchronism of Example 1 is more coordinated, which is more beneficial to reducing the overall deformation and internal shear of the tire.

[0100] The comparison of the crown arc contour shapes of the tires of Example 1 and Comparative Example 1 after inflation to the target air pressure is as Figures 8 - 9 shown. It can be seen from the figure that the crown arc contour shapes of Example 1 and Comparative Example 1 are basically equivalent and the performances are close.

[0101] (3) Loading deformation

[0102] To simulate the tire deformation under market usage conditions, at a standard air pressure of 900 kPa, the loading deformation comparisons of the tires of Example 1 and Comparative Example 1 were carried out using single-tire loads of 4.125 t and 5.3 t respectively. The comparison results are shown in Table 4:

[0103] Table 4 Comparison results of loading deformation of the tires of Example 1 and Comparative Example 1

[0104]

[0105] As can be seen from Table 4, under the above test conditions, the tires of Example 1 and Comparative Example 1 are basically the same in static load radius of the outer contour and cross-sectional width under load, which can ensure the tire performance.

[0106] (4) Imprint analysis

[0107] To simulate the tire grounding situation under market usage conditions, at a standard air pressure of 900 kPa, single-tire loadings of 4.125 t and 5.3 t were used for grounding analysis. The imprint analysis results of the tires of Example 1 and Comparative Example 1 are as Figures 10 - 11 shown in Table 5 - 6:

[0108] Table 5 Imprint analysis results of the tires of Example 1 and Comparative Example 1 at 900 kPa and 4.125 t

[0109]

[0110] Table 6 Imprint analysis results of the tires of Example 1 and Comparative Example 1 at 900 kPa and 5.3 t

[0111]

[0112] Through imprint analysis, under the usage conditions of 900 kPa and 4.125 t, the rectangularity rate of Example 1 is higher than that of Comparative Example 1, indicating that the tire of Example 1 has better grounding and an advantage in wear life; under the usage conditions of 900 kPa and 5.3 t, from the perspective of the imprint dimension in Table 6, Example 1 is comparable to Comparative Example 1.

[0113] (5) Radial deflection / stiffness

[0114] The deflection and radial stiffness during tire usage are also important references for characterizing tire performance. In the experiment, an inflation pressure of 900 kPa and single-tire loadings of 4.125 t and 5.3 t were used to compare the deflection and radial stiffness of the tires of Example 1 and Comparative Example 1 under relevant conditions. The test results are shown in Table 7:

[0115] Table 7 Test results of radial deflection and radial stiffness of the tires of Example 1 and Comparative Example 1

[0116]

[0117]

[0118] Through comparative analysis, under an inflation pressure of 900 kPa and single-tire loadings of 4.125 t and 5.3 t, the radial deflection and stiffness of the tires of Example 1 and Comparative Example 1 are comparable, which can meet the tire performance.

[0119] (6) Durability

[0120] Under the service conditions of 900 kPa, 4.125 t and 5.3 t, the tires of Example 1 and Comparative Example 1 were respectively analyzed in terms of the compression and tension of the carcass material, the maximum principal strain at the belt edge, and the shear strain at the belt edge. The comparison results are as Figures 12 - 14 shown. The results show that the 1# belt 3 is in a compressed state, and the compression of the tire in Example 1 is greater, which is not beneficial to the durability of the 1# belt 3; the 2# belt 4 is also in a compressed state under both conditions, but the compression in Example 1 is reduced, which is more beneficial to durability; the compression of the 0° belt 2 is also reduced in Example 1. Combining the failures in the laboratory and indoors, most of them start from the damage point at the edge of the 2# belt 4. Example 1 can significantly reduce the compression state at the edge of the 2# belt 4, which is more beneficial to the durability performance of the tire.

[0121] The reduction of the principal strain and shear strain at the edge is of good significance for characterizing the optimization of the fatigue performance and stress distribution at the belt edge. Under the service conditions of 900 kPa, 4.125 t and 5.3 t, the maximum principal strain and shear strain at the belt edge were analyzed. The analysis results are as Figures 15 - 18 shown. The results show that for the 1# belt 3, 2# belt 4, and 0° belt 2 in Example 1 under the load conditions of 4.125 t and 5.3 t, the full-cycle amplitudes of the maximum principal strain and the full-cycle amplitudes of the shear strain at the edge are both reduced, indicating that the tire of Example 1 has better durability performance at the belt edge.

[0122] In summary, compared with the conventional film design of Comparative Example 1, after adopting the nested component 1 of Example 1:

[0123] 1) The inflated outer diameter and inflated section width are equivalent to those of Comparative Example 1, meeting the requirements;

[0124] 2) The trend of the outer contour expansion change of Example 1 is close to that of Comparative Example 1, and the crown arc grows synchronously, but the synchronism of the shoulder in Example 1 is better;

[0125] 3) The crown arc profiles of Example 1 and Comparative Example 1 are basically equivalent;

[0126] 4) The static load radius and section width under load of Example 1 and Comparative Example 1 are basically equivalent;

[0127] 5) The contact patch after loading of Example 1 and Comparative Example 1 is basically equivalent, but the rectangularity of Example 1 is better under the conditions of 900 kPa and 4.125 t;

[0128] 6) The radial stiffness and deflection of Example 1 and Comparative Example 1 are basically equivalent;

[0129] 7) Durability

[0130] a) From the perspective of the compression dimension of the skeleton material: In Example 1, the compression degree of the 1# belt layer 3 shows an increasing trend, with a numerical change range of 40%; the compression degree of the 2# belt layer 4 shows a decreasing trend, with a numerical change range of 50%; the compression degree of the 0° belt layer 2 shows a decreasing trend, with a numerical change range of 4%. Combining with the analysis of the market failure mode, the decrease in the compression degree of the 2# belt layer 4 can significantly reduce the shoulder void ratio in the market.

[0131] b) From the perspective of mechanical indexes: In Example 1, the maximum principal strain and the interlayer & end point shear strain of the 1# belt layer 3 show a decreasing trend, with a numerical change range exceeding 20%; the maximum principal strain and the end point shear strain of the 2# belt layer 4 show a decreasing trend, with a numerical change exceeding 10%; the maximum principal strain and the end point shear strain of the 0° belt layer 2 show a decreasing trend, and the overall durability performance shows an improving trend.

[0132] Comparative Example 2

[0133] The difference from Example 1 is that the nested component 1 of Comparative Example 2 includes the following components in parts by weight: 100 parts of NR, 58 parts of N326, 8 parts of zinc oxide, 2 parts of tackifying resin SP1068, 0.5 part of cobalt caprylate, 2 parts of antioxidant 6PPD, 5 parts of antioxidant HODT20, 3 parts of RA-65, 0.1 part of 1-MT, and 1.3 parts of DZ.

[0134] Perform performance tests on the nested component 1 of Example 1 and Comparative Example 2, and the test results are shown in Table 8:

[0135] Table 8 Performance test results of the nested component 1 of Example 1 and Comparative Example 2

[0136]

[0137]

[0138]

[0139] It can be seen from Table 8 that after adopting the formula of the nested component 1 of Example 1, the rubber after high-temperature vulcanization has: 1) higher hardness and modulus, which can make it have better modulus matching with skeleton materials such as steel wires, so as to disperse stress and reduce the failure rate of tire products; 2) higher steel wire extraction force, indicating that the adhesion strength with steel wires is improved, which is beneficial to improving the load-bearing capacity and durability of tire products.

Claims

1. A nested component adapted to the end point of the belt layer, characterized in that: The nested component (1) is C-shaped and the width of the upper end face is greater than the width of the lower end face; when the tire belt layer is a 0° belt layer (2), a 1# belt layer (3), a 2# belt layer (4) and a 3# belt layer (5) structure, the nested component (1) is wrapped at the end points of the 1# belt layer (3) and the 2# belt layer (4), and the upper end face of the nested component (1) of the 1# belt layer (3) exceeds the end point of the 3# belt layer (5), the upper end face of the nested component (1) of the 2# belt layer (4) exceeds the inner end point of the 0° belt layer (2) but does not exceed the end point of the 3# belt layer (5), and the lower end face of the nested component (1) of the 2# belt layer (4) exceeds the end point of the 1# belt layer (3); When the tire belt layer is a structure of a 1# belt layer (3), a 2# belt layer (4), a 3# belt layer (5) and a 4# belt layer, the nested component (1) is wrapped around the end points of the 1# belt layer (3), the 2# belt layer (4) and the 3# belt layer (5), and the upper and lower end surfaces of the nested component (1) of the 2# belt layer (4) respectively exceed the end points of the 3# belt layer (5) and the 1# belt layer (3).

2. The nested component adapted to the end point of the belt layer according to claim 1, characterized in that Both ends and the inner sides of the corners of the nested component (1) are chamfered.

3. The nested component adapted to the end point of the belt layer according to claim 1, characterized in that: The thickness of the upper and lower end surfaces of the nested component (1) gradually decreases from the corner to the end point.

4. The nested component adapted to the end point of the belt layer according to claim 1, characterized in that: The width difference between the upper and lower end surfaces of the nested component (1) is 10-25 mm.

5. The nested component adapted to the end point of the belt layer according to claim 4, characterized in that: The width of the upper end surface of the nested component (1) is 47 mm, and the width of the lower end surface is 22 mm.

6. The nested component adapted to the end point of the belt layer according to claim 1, characterized in that: The upper end surface of the nesting component (1) is inclined upward by 3°-5°, and the lower end surface is inclined downward by 2°-3°.

7. The nested component adapted to the end point of the belt layer according to claim 1, characterized in that: The nested component (1) comprises the following components in parts by weight: 100 parts of natural rubber, 60-62 parts of carbon black, 8 parts of zinc oxide, 2 parts of tackifying resin, 0.5 parts of adhesion promoter, 7.5-8 parts of antioxidant, 5-5.5 parts of methylene donor adhesive, 1.5-2.2 parts of resorcinol adhesive, and 1.3 parts of vulcanization accelerator.

8. The nested component adapted to the end point of the belt layer according to claim 7, characterized in that: The carbon black is N326; the tackifying resin is SP1068; the adhesion promoter is cobalt decanoate; the antioxidant includes 2 parts of 6PPD and 5.5-6 parts of HODT20; the methylene donor adhesive is at least one of RA-65, HMMM and HMT; the resorcinol adhesive is at least one of B-20-S, SL3020 and R-80; and the vulcanization accelerator is DZ.

9. A forming process of a nested component adapted to the end point of a belt layer in tire production according to any one of claims 1 to 8, characterized in that: The following steps are involved: S1: using a belt layer adsorption structure (6) to absorb the belt layer to be attached to the nested component (1); S2: using the left and right combined pressure feeding mechanisms (7) to feed the nested components (1) to both ends of the belt layer and nest them into the two ends of the belt layer; S3: Forming drum rotation and lamination; S4: rolling the nested component (1) inward from the end point of the belt layer by a rolling mechanism (8) to complete the lamination of the nested component (1) on the belt layer; S5 follows the above-mentioned operation to sequentially bond the nested components (1) at both ends of the 1# belt layer (3) and the 2# belt layer (4), or the nested components (1) at both ends of the 1# belt layer (3), the 2# belt layer (4), and the 3# belt layer (5), and then shapes and bonds the belt layers in the order of 0° belt layer (2), 1# belt layer (3), 2# belt layer (4), and 3# belt layer (5), or 1# belt layer (3), 2# belt layer (4), 3# belt layer (5), and 4# belt layer.

10. The forming process of the nested component adapted to the end point of the belt layer in tire production according to claim 9, characterized in that: In step S4, the rolling speed is 120±5 r / min, and the rolling pressure is 0.7±0.05 MPa.

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