Method for solving edge warping of wear-resistant rubber of all-steel tire blank of TBR

Abstract

The invention relates to a method for solving edge warping of wear-resistant rubber of a TBR all-steel tire blank, and belongs to the technical field of tire manufacturing. When the edge warping of the wear-resistant rubber is located at the inner end point of a tire bead part, the material structure of the tire bead part and the difference value between the flat width of the tire blank and the width of a forming drum are determined; if the material structure and / or the difference value of the tire bead part do not meet the standard, adjusting to the standard, tracking and adjusting whether the edge warping problem of the wear-resistant rubber occurs at the inner end point of the tire blank ring part after improvement, and if no problem occurs, indicating that the problem is solved; if problems still occur, the viscidity of the sidewall rubber sheet and the viscidity of the airtight layer are adjusted to standard values, and the technical problems that in the prior art, specific incentives of edge warping of the wear-resistant rubber cannot be determined, and edge warping of the wear-resistant rubber cannot be fundamentally solved can be solved.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of tire manufacturing, and particularly relates to a solution to the edge lifting of the wear-resistant rubber of a TBR all-steel tire blank. BACKGROUND

[0002] With the progress of society and the rapid development of the transportation industry, the safety performance of tires has become one of the core focuses of public attention. In particular, in the field of manufacturing truck and bus radial tires (TBR), higher requirements are placed on improving the overall quality and durability of tires. However, in the production process of TBR all-steel tires, a common technical challenge is the edge lifting of the wear-resistant rubber. It is worth noting that this problem is not unique to a single manufacturer, but is a common problem in the industry, which is manifested in the following aspects: The edge lifting position is consistent and occurs at the inner end point position of the wear-resistant rubber in the bead portion; This phenomenon can manifest as edge lifting occurring on both the upper and lower molds or only on one side, and the edge lifting shape can be either continuous or distributed in a point-like manner; The appearance of the edge lifting presents an irregular wavy shape.

[0003] The lack of specific analysis of the causes of the edge lifting of the wear-resistant rubber in existing literature undoubtedly increases the difficulty of determining the exact cause of the edge lifting and further hinders technical progress in fundamentally solving this problem. SUMMARY

[0004] In view of the various deficiencies of the prior art, a solution to the edge lifting of the wear-resistant rubber of a TBR all-steel tire blank is proposed to solve the technical problems that the prior art cannot determine the specific causes of the edge lifting of the wear-resistant rubber and cannot fundamentally solve the edge lifting of the wear-resistant rubber.

[0005] To achieve the above-mentioned purpose, the present application provides the following technical solutions: A solution to the edge lifting of the wear-resistant rubber of a TBR all-steel tire blank, comprising the following steps: When the edge lifting of the wear-resistant rubber occurs at the inner end point position of the bead portion, the material structure of the bead portion and the difference between the flat width of the tire blank and the width of the forming drum are determined; If the material structure of the bead portion and / or the difference do not meet the standard, they are adjusted to the standard, and it is tracked whether the edge lifting of the wear-resistant rubber occurs at the inner end point of the bead portion after the adjustment and improvement, and if not, it indicates that the problem is solved; if it still occurs, the tackiness of the sidewall rubber and the tackiness of the air barrier layer are adjusted to the standard value.

[0006] The technical scheme is further provided with the structure of the bead part material, which refers to the distance between the outer end point of the sidewall rubber sheet and the outer end point of the wear-resistant rubber. The adjustment of the structure of the bead part material to the standard refers to the adjustment of the distance between the outer end point of the sidewall rubber sheet and the outer end point of the wear-resistant rubber to the distance standard value.

[0007] The technical scheme is further provided with the structure of the bead part material, which refers to the distance between the outer end point of the sidewall rubber sheet and the outer end point of the wear-resistant rubber. The distance between the inner end point and the outer end point of the sidewall rubber sheet is divided into multiple gradients, a fitting line graph is drawn, and the best distance between the inner end point and the outer end point of the sidewall rubber sheet is obtained through regression analysis; the distance between the outer end point of the sidewall rubber sheet and the outer end point of the wear-resistant rubber corresponding to the best distance is the distance standard value between the outer end point of the sidewall rubber sheet and the outer end point of the wear-resistant rubber.

[0008] The technical scheme is further provided with the structure of the bead part material, which refers to the distance between the outer end point of the sidewall rubber sheet and the outer end point of the wear-resistant rubber.

[0009] The technical scheme is further provided with the structure of the bead part material, which refers to the distance between the outer end point of the sidewall rubber sheet and the outer end point of the wear-resistant rubber.

[0010] The technical scheme is further provided with the structure of the bead part material, which refers to the distance between the outer end point of the sidewall rubber sheet and the outer end point of the wear-resistant rubber.

[0011] The technical scheme is further provided with the structure of the bead part material, which refers to the distance between the outer end point of the sidewall rubber sheet and the outer end point of the wear-resistant rubber. The adhesion of the air-tight layer and the adhesion of the sidewall rubber sheet are divided into multiple gradients respectively. The DOE experiment is carried out to verify the significance of the influence of the adhesion of the air-tight layer and the adhesion of the sidewall rubber sheet on the edge lifting failure rate of the wear-resistant rubber. The best combination parameters of the adhesion of the air-tight layer and the adhesion of the sidewall rubber sheet are obtained through the DOE experiment response optimizer combined with regression analysis, that is, the standard value of the adhesion of the sidewall rubber sheet and the standard value of the adhesion of the air-tight layer are obtained.

[0012] The technical scheme is further provided with the structure of the bead part material, which refers to the distance between the outer end point of the sidewall rubber sheet and the outer end point of the wear-resistant rubber.

[0013] The technical scheme is further provided with the structure of the bead part material, which refers to the distance between the outer end point of the sidewall rubber sheet and the outer end point of the wear-resistant rubber.

[0014] The beneficial effects of the present application are: The targeted analysis generates the adhesive standard of the wear-resistant rubber, the principle of the material design of the ring part, through the multi-dimensional collaborative measures, the adhesion stability of the wear-resistant rubber in the ring part area is effectively improved, the occurrence probability of the edge lifting defect is obviously reduced, the adverse effect caused by the edge lifting of the wear-resistant rubber is fundamentally solved, the production influence and the unstable quality caused by the repeated adjustment of the forming process by the process personnel to blindly improve the adhesion of the rubber are avoided, and the application prospect and the popularization value are good. BRIEF DESCRIPTION OF DRAWINGS

[0015] Figure 1 It is a TBR full steel tire embryo material distribution schematic diagram; Figure 2 It is an embryo appearance diagram with the wear-resistant rubber edge lifting problem; Figure 3 It is a bead part material structure schematic diagram in the embodiment of the application; Figure 4 It is a fitting line diagram of the inner and outer end point distance of the sidewall rubber sheet in the embodiment of the application; Figure 5 It is a viscosity standardization response diagram in the embodiment of the application; Figure 6 It is a wear-resistant rubber edge lifting factor regression equation diagram in the embodiment of the application; Figure 7 It is an optimizer display diagram in the embodiment of the application; Figure 8 It is a viscosity contour diagram in the embodiment of the application; Figure 9 It is a wear-resistant rubber defect regression equation diagram in the embodiment of the application; Figure 10 It is a flowchart of a TBR full steel tire embryo wear-resistant rubber edge lifting solution in the embodiment of the application. DETAILED DESCRIPTION

[0016] In order to make the personnel in the art better understand the technical solutions of the application, the technical solutions of the application will be described clearly and completely below in combination with the drawings of the application, and other similar embodiments obtained by the personnel in the art without creative labor on the basis of the embodiments in the application shall belong to the protection scope of the application. In addition, the direction words mentioned in the following embodiments, such as “up”, “down”, “left”, “right” and the like are only the directions of the drawings, therefore, the direction words used are used to illustrate but not to limit the application.

[0017] In view of the wear-resistant rubber edge lifting problem of the TBR full steel tire embryo in the prior art, the inventor analyzes the actual product structure and the process flow in depth, and combines the tire embryo material distribution schematic diagram (see the attached Figure 1 ), the tire embryo appearance diagram (see the attached Figure 2The study included images of the internal state of the cut abrasion-resistant adhesive and systematically investigated the edge curling phenomenon of the adhesive.

[0018] Based on observations and analysis, the inventors discovered that the edge curling of the wear-resistant rubber mainly occurs at the inner end point of the wear-resistant rubber on the tire bead, specifically from the inner end point of the wear-resistant rubber on the tire sidewall to the tire bead (see Appendix). Figure 1 Compared to tire blanks without wear-resistant rubber edge curling issues, this area exhibits significant crease defects, which can be distributed continuously around the circumference or in localized point-like patterns. Based on this characteristic, the inventors further summarized several potential causes that may lead to wear-resistant rubber edge curling, including but not limited to: 1. Insufficient adhesion of the wear-resistant adhesive on the tire sidewall; 2. The material design of the ring has structural defects; 3. Poor compatibility of production equipment causes the wear-resistant rubber to stick to the molded drum bladder, making it difficult to separate them smoothly during tire removal; 4. Insufficient pressing pressure of the sector blocks caused the rubber layers to separate. 5. The size and structure of the sector block do not match the preform ring, affecting the molding quality.

[0019] In existing technologies, relevant technicians typically take the following measures from the perspective of molding process control to alleviate the problem of wear-resistant adhesive curling: 1. Reduce the extrusion speed in the semi-finished product process to improve the edge tack of the abrasion-resistant adhesive; 2. Apply gasoline to the wear-resistant rubber parts during the molding process to enhance the adhesion between components; 3. Increase the pressing pressure of the sector blocks to make the bonding between the various rubber components tighter; 4. Modify the sector block structure to better suit the shape of the tire ring.

[0020] However, the above methods are mostly empirical adjustments and fail to make systematic improvements from the perspective of the intrinsic mechanism of wear-resistant adhesive curling. Therefore, they can only alleviate the problem to a certain extent and cannot fundamentally eliminate the wear-resistant adhesive curling defect.

[0021] To this end, the inventors conducted further in-depth technical research on the root causes of the wear-resistant adhesive warping and summarized the following three key factors: 1. Insufficient adhesive performance of the ring-shaped adhesive. In the semi-finished product manufacturing process, to improve production efficiency, the extrusion process temperature is often exceeded from the reasonable control range, leading to a violent oxidation reaction of rubber molecules. This process affects the vulcanization characteristics of the rubber, manifested as a decrease in crosslinking density and uneven distribution of crosslinked structures, thereby weakening the physical adsorption and chemical bonding ability between rubber molecules and compounding agents. Under these conditions, compounding agents are prone to migrate within the rubber compound and precipitate on the surface of the abrasion-resistant rubber, forming blooming, further reducing the adhesion strength between materials, and ultimately causing edge curling defects.

[0022] Furthermore, through observation of the cut cross-section of the tire blank and verification by process simulation, it was found that when the adhesion of the airtight layer is lower than the critical value, the interface between the airtight layer and the sidewall rubber is easily separated by the friction force of the molding capsule and the shrinkage force of the rubber; the low adhesion of the sidewall rubber leads to poor adhesion between it and the end of the wear-resistant rubber, and the edge lifts up due to material separation during tire removal.

[0023] 2. The material design of the ring has structural defects. During the material layout design stage, due to unreasonable position matching between the wear-resistant rubber and other adjacent materials, improper setting of the saturation of the ring material, and lack of scientific basis for the design of the transition area between different materials, the wear-resistant rubber cannot achieve good adhesion and fixation in the ring area after the tire blank is formed, resulting in local voids or even peeling, which in turn induces edge curling.

[0024] 3. Poor compatibility with production equipment During the molding process, the friction coefficient between the bladder material and the wear-resistant rubber is relatively high, making it difficult for the contact surfaces of the two to separate smoothly during tire removal. Especially under high temperature and high pressure conditions, a strong adhesion is generated between the wear-resistant rubber and the bladder, causing uneven stress on the wear-resistant rubber during separation, resulting in edge curling defects in the bezel area.

[0025] In view of the above-mentioned fundamental reasons, the inventors conducted in-depth research on two directions: improving the adhesion performance of the rim rubber and optimizing the layout design of the rim material. They proposed a systematic and highly operable solution, which aims to fundamentally solve the problem of edge lifting of the wear-resistant rubber in TBR all-steel tire blanks and improve the product qualification rate and overall tire performance.

[0026] Based on the above analysis, this invention provides a solution for the edge curling of the wear-resistant rubber on a TBR all-steel tire blank. Please refer to [link / reference]. Figure 10 This includes the following steps: S100. Based on the appearance and cross-section of the tire blank, determine the distribution of the wear-resistant rubber curling edge. When the wear-resistant rubber curling edge is located at the inner end point of the bead section, determine the material structure of the bead section and the difference between the flat width of the tire blank and the width of the molded drum. S200、If the bead portion material structure and / or the difference do not meet the standard, adjust to the standard, track whether the tire body bead inner end point appears the wear-resistant rubber edge lifting problem after the adjustment improvement, if the problem does not appear, it means that the problem is solved; if the problem still appears, adjust the adhesion of the sidewall rubber sheet and the air tightness layer to the standard value.

[0027] In the TBR all-steel tire body wear-resistant rubber edge lifting solution of the embodiment of the application, please refer to Figure 3 , the bead portion material structure refers to the distance between the sidewall rubber sheet and the wear-resistant rubber, which is the horizontal distance between the outer end point of the sidewall rubber sheet and the outer end point of the wear-resistant rubber. The smaller the distance is, the more thick and stiff the material at the edge of the tire body is, which is easy to lift up; wherein, adjusting the bead portion material structure to the standard refers to adjusting the distance between the sidewall rubber sheet and the wear-resistant rubber to the standard value of the distance.

[0028] Further, the determination method of the standard value of the distance between the sidewall rubber sheet and the wear-resistant rubber is: Divide the distance between the inner and outer end points of the sidewall rubber sheet into multiple gradients, draw a fitting line graph, and obtain the optimal distance between the inner and outer end points of the sidewall rubber sheet through regression analysis. The distance between the sidewall rubber sheet and the wear-resistant rubber corresponding to the optimal distance is the standard value of the distance between the sidewall rubber sheet and the wear-resistant rubber.

[0029] Specifically, based on the equipment bonding capacity and the material design constraint condition, the distance gradient between the inner and outer end points of the sidewall rubber sheet is set as: Minimum limit: the distance between the inner and outer end points of the sidewall rubber sheet is 110 mm, based on the corresponding relationship in the technical standard, the corresponding distance between the sidewall rubber sheet and the wear-resistant rubber is 5 mm, which avoids excessive accumulation caused by material overlap.

[0030] Maximum limit: the distance between the inner and outer end points of the sidewall rubber sheet is 130 mm, based on the corresponding relationship in the technical standard, the corresponding distance between the sidewall rubber sheet and the wear-resistant rubber is 25 mm, which prevents insufficient steel wire bead material.

[0031] Gradient interval: 4 mm step, divide 6 test gradients (110 mm, 114 mm, 118 mm, 122 mm, 126 mm, 130 mm), cover the complete design space from minimum to maximum, as shown in Table 1, wherein, considering the measurement tolerance, the actual distance is obtained by the distance between the inner and outer end points of the sidewall rubber sheet ± 2 mm.

[0032] Table 1: Under the standardized production environment, 150 groups of tire body samples (25 groups of gradients per group) are produced according to the gradient scheme, the actual rubber sheet positioning value (such as 124-127 mm for the actual positioning of the 126 mm gradient) and the corresponding wear-resistant rubber edge lifting defect rate are recorded, as shown in Table 2.

[0033] Table 2: The actual distance of each gradient and the average defect rate are counted to establish a data set (for example, the defect rate is 16.7% when the distance is 130 mm, and the defect rate is 43.3% when the distance is 110 mm), and it is preliminarily concluded that the defect rate increases nonlinearly with the increase of the distance. The fitting line graph is drawn with the inner and outer end point distance of the sidewall rubber sheet as the horizontal coordinate and the wear-resistant rubber edge lifting defect rate as the vertical coordinate, please refer to Figure 4 , Figure 4 The inner and outer end point distance of the sidewall rubber sheet is the rubber sheet positioning. It can be directly concluded from Figure 4 that the two are in a nonlinear relationship, and the defect rate increases significantly with the decrease of the inner and outer end point distance of the sidewall rubber sheet (i.e., the sidewall rubber sheet is close to the outer end point of the wear-resistant rubber), which verifies that the too small distance leads to too thick material and increased stiffness, which is the main cause of edge lifting. A mathematical model is established by using quadratic regression analysis: Defect rate = 14.83-0.2319x+0.000916x², wherein x is the inner and outer end point distance of the sidewall rubber sheet, the unit is mm, R² = 94.7%, adjusted R² = 91.1%, and the model is significant.

[0034] The derivative of the regression equation is solved and the equation is solved to determine that the optimal inner and outer end point distance of the sidewall rubber sheet is 126.58 mm, corresponding to the theoretical minimum defect rate of 15.3%. In combination with the construction feasibility and the defect rate tolerance, the inner and outer end point distance of the sidewall rubber sheet is adjusted to 125 mm (the defect rate increases to 15.45%, only increases by 0.15%), and the corresponding end point distance of the sidewall rubber sheet and the wear-resistant rubber is 15 mm, which balances the theoretical optimal value and the actual production complexity. Based on this, the optimal inner and outer end point distance of the sidewall rubber sheet is 125 mm±2 mm (considering the measurement tolerance), and the standard value of the distance between the sidewall rubber sheet and the wear-resistant rubber is 15 mm±2 mm (considering the measurement tolerance).

[0035] Through the systematic method of gradient test→fitting analysis→regression modeling→engineering optimization, the influence law of the end point distance between the sidewall rubber sheet and the wear-resistant rubber on the edge lifting defect rate is explained, and the limitation of traditional empirical adjustment is broken through. Based on the standardization of the design parameters of the quantitative model, the precise control of the material layout of the circle part is realized, and a reusable scientific decision-making framework is provided for the tire structure optimization.

[0036] In the TBR all-steel tire blank wear-resistant rubber edge lifting solution of the embodiment of the present application, the tire blank flat width is the distance between the two steel wire rings in the tire blank, and the standard value of the difference between the tire blank flat width and the forming drum width is 85 mm-88 mm.

[0037] Specifically, to establish the standardized design rule of the difference ΔL between the flat width of the tire blank and the width of the forming drum, a plurality of specifications of tires are selected for benchmarking test, 385 / 65R22.5 (bad rate of edge lifting 95.89%) is taken as a target specification, 295 / 75R22.5, 11R22.5 and 295 / 80R22.5 (ΔL≤88mm, no edge lifting problem) are taken as control specifications. The flat width of the tire blank and the width of the forming drum of each specification are measured, and ΔL is calculated; the edge lifting state of the wear-resistant rubber of 50 tire blanks is calibrated, and the correlation between ΔL and the bad rate of edge lifting is counted, as shown in Table 3.

[0038] Table 3: It can be seen from Table 3 that when ΔL is 86mm or 88mm, the bad rate of edge lifting of the wear-resistant rubber is 0%; when ΔL≥90mm, the edge lifting problem is significant (for example, ΔL=96mm of 385 / 65R22.5 specification, the bad rate is 95.89%). In combination with the attached Figure 3 When ΔL is too large, the bead wire is far away from the inner end point of the forming drum locking block, the material pressing force is reduced, the wear-resistant rubber and the sidewall rubber sheet are not tightly bonded, and the edge lifting is caused by the friction force of the capsule when the tire is removed.

[0039] In order to improve the universality of the forming drum as much as possible, ΔL is set to 85mm-88mm, the width of the forming drum is adjusted, and it is ensured that 85mm≤ΔL≤88mm. For the target specification, the original forming drum width 636mm is adjusted to 647mm, ΔL=85mm, 50 tire blanks are continuously tracked, the number of bad ones is 0, and the bad rate of edge lifting of the wear-resistant rubber is reduced to 0%. At the same time, the cross section of the adjusted tire blank is cut and detected, the material distribution uniformity (no local accumulation or void), the bonding tightness of the wear-resistant rubber and the sidewall rubber sheet (no delamination or folding defect), and the position of the bead wire meet the CTL cross section design standard.

[0040] ΔL=85mm is extended to other 22.5-inch specifications (such as 315 / 80R22.5 and 445 / 50R22.5), and the results after adjustment show that: After adjusting the drum width, the bad rate of edge lifting of the original ΔL≥90mm specification (such as ΔL=93mm of 315 / 80R22.5 and ΔL=94mm of 445 / 50R22.5) is reduced to 0%, and the cross section performance (strength, durability) meets the industry standard.

[0041] By quantitatively controlling ΔL, the blindness of relying on experience adjustment in the traditional process is solved; the rule is suitable for tires of the same inch level, has wide applicability, and simplifies the research and production process.

[0042] In the tire blank edge lifting solving method of the TBR full steel tire of the embodiment, the determination method of the standard value of the adhesion of the sidewall rubber sheet and the standard value of the adhesion of the air tight layer is: The adhesion of the air tight layer and the adhesion of the side rubber sheet are respectively divided into multiple gradients; A DOE experiment is carried out to verify the significance of the adhesion of the air tight layer and the adhesion of the side rubber sheet on the wear-resistant rubber edge lifting failure rate. The optimal combination parameters of the adhesion of the air tight layer and the adhesion of the side rubber sheet are obtained by the DOE experiment response optimizer combined with regression analysis, that is, the standard value of the adhesion of the side rubber sheet and the standard value of the adhesion of the air tight layer are obtained.

[0043] Specifically, 300 tire blanks (specification 385 / 65R22.5) are taken as samples, the adhesion data (measured by an adhesion tester, unit: N) of the air tight layer and the side rubber sheet are collected, and the corresponding wear-resistant rubber edge lifting states are recorded. It is found through measurement that when the adhesion of the side rubber sheet is less than 6N, more than 90% of the samples have the problem of wear-resistant rubber edge lifting, therefore, 6N is taken as the lower limit of the adhesion of the side rubber sheet, and when the adhesion of the side rubber sheet is greater than 8N, more than 95% of the samples do not have the problem of wear-resistant rubber edge lifting, therefore, 8N is taken as the upper limit of the adhesion of the side rubber sheet. Based on the same rule, 6N is taken as the lower limit of the adhesion of the air tight layer, and 9N is taken as the upper limit of the adhesion of the air tight layer. Based on the measurement data and process boundaries, the gradients of the two parameters are set, and each gradient interval is 0.5N, as shown in Tables 4 and 5, and the actual adhesion considers a measurement tolerance of ±0.3N.

[0044] Table 4: Table 5: A DOE experiment is carried out, double factors (adhesion of the side rubber sheet and adhesion of the air tight layer) x two levels (minimum value and maximum value), full factor design (2² DOE) is adopted, containing 2 times of imitation and center point verification, the response variable is the wear-resistant rubber edge lifting failure rate, divided into 2 groups (1 group per day), a total of 10 groups of tests (containing 2 center points), randomized running sequence, reducing the influence of interference factors, the test results are shown in Table 6.

[0045] Table 6: The Minitab software is used to analyze the adhesion standardization response graph (see Figure 5 ), the wear-resistant rubber edge lifting factor regression equation graph (see Figure 6 ), the optimizer display graph (see Figure 7 ), the adhesion contour graph (see Figure 8 ) and the wear-resistant rubber failure regression equation graph (see Figure 9 ), and the specific analysis is as follows: Figure 5In the diagram, the vertical axis represents factors such as airtight layer adhesion (A), sidewall film adhesion (B), and interaction (A×B), while the horizontal axis represents the standardized effect value (absolute value) of each factor on the defect rate. A significance threshold (α=0.05) is defined; factors exceeding this threshold are considered significant main effects. Figure 5 It can be concluded that the standardized effect values ​​of both the airtight layer adhesion (A) and the sidewall rubber adhesion (B) exceed the threshold, indicating that their independent effects are significant. Simultaneously, the interaction effect (A×B) also exceeds the threshold, indicating that their synergistic effect has an additional impact on the defect rate.

[0046] Depend on Figure 6 The regression model can be derived as follows: The defect rate is calculated as: 0.9105 − 0.07238A − 0.10117B + 0.008042AB. Here, the coefficient of the airtight layer viscosity (A) is negative; increasing viscosity decreases the defect rate. The coefficient of the sidewall rubber viscosity (B) is also negative; increasing viscosity decreases the defect rate. The coefficient of the interaction term (AB) is positive; when both viscosities are high, the interaction may slightly offset the defect-reducing effect of either viscosity alone. R-Sq (adjusted) = 99.98%, indicating a highly reliable model. The p-value = 0.000 (P < 0.001), indicating extremely high significance of the main effects and the interaction, ruling out the possibility of random error.

[0047] The tackiness of the airtight layer directly affects the adhesion between the airtight layer and the sidewall rubber; insufficient tackiness leads to interface separation. The tackiness of the sidewall rubber determines the adhesion strength between the sidewall rubber and the abrasion-resistant rubber; insufficient tackiness causes the abrasion-resistant rubber edges to lift. When both the tackiness of the airtight layer (A) and the tackiness of the sidewall rubber (B) are low, their combined effect causes a sharp increase in the defect rate. Therefore, it is necessary to simultaneously control the synergistic effects of A, B, and AB to minimize the defect rate. Through Pareto analysis and regression model verification, the tackiness of the airtight layer, the tackiness of the sidewall rubber, and their interaction were identified as significant main effects on the abrasion-resistant rubber edge lifting defect rate.

[0048] Depend on Figure 7 It can be concluded that when the tack of the sidewall rubber is 6.997N (7N gradient) and the tack of the airtight layer is 8.69N (8.5N gradient), the rate of edge curling of the abrasion-resistant rubber approaches 0. Meanwhile, Figure 8 The combined effects of sidewall rubber adhesion and airtight layer adhesion on the wear-resistant rubber warping defect rate are illustrated using contour lines (topography lines). This visually presents the defect rate distribution under different adhesion combinations. Figure 8 It was verified that when the sidewall rubber tack was 6.997N (7N gradient) and the airtight layer tack was 8.69N (8.5N gradient), the defect rate was less than 0.025, which met the production requirements. Figure 9 The relationship between stickiness and defect rate is quantified using an equation: regression model. The adverse rate = 0.897-0.0724A-0.1012B+0.00804AB, which is a final optimized model after simplification, only significant main effects (A, B) and interaction terms (AB) are reserved by stepwise regression or statistical significance screening (P<0.05), only the variables with the strongest explanatory power for the adverse rate are reserved to ensure that the model is simple and easy to engineer. At the same time, it directly gives the operable viscosity control range (A=6.98N, B=8.62N) and the confidence interval (95% confidence interval: -0.0367~0.0440) for predicting the adverse rate, which is convenient for production site execution. Based on this, the standard value of the viscosity of the sidewall rubber sheet is preferably 7N±0.3N, and the standard value of the viscosity of the air tight layer is preferably 8.5N±0.3N.

[0049] For the 385 / 65R22.5 specification, the original sidewall rubber sheet viscosity is 6.0-6.3N, the air tight layer viscosity is 6.0-6.3N, and the corresponding edge lifting adverse rate is 95.89%. The sidewall rubber sheet viscosity is adjusted to 7N (6.9N-7.3N), and the air tight layer viscosity is adjusted to 8.5N (8.4N-8.8N) for testing, and the adverse rate of the edge lifting of the wear-resistant rubber of 50 tire blanks is 0.0028, which falls within the 95% confidence interval and the prediction interval. At the same time, the cross section of the adjusted tire blank is cut and detected, the material distribution uniformity (no local accumulation or voids), the adhesion density of the wear-resistant rubber and the sidewall rubber sheet (no delamination or folding defects), and the position of the steel wire ring meet the CTL cross section design standard.

[0050] Through DOE testing and regression analysis, the influence of viscosity on edge lifting is quantified, the interaction of the two viscosity parameters is revealed, and it is proved that a single parameter cannot solve the problem, forming a reusable rubber viscosity research process. By precisely controlling the viscosity values of the air tight layer and the sidewall rubber sheet, the edge lifting problem of the wear-resistant rubber can be effectively eliminated, and the production stability and product quality can be improved. The method is suitable for the whole series of TBR tires, and provides a scientific basis for rubber process design and production control.

[0051] The above has described the present application in detail, the above is only a preferred embodiment of the present application, which cannot limit the scope of the present application, that is, any equivalent change and modification made within the scope of the present application should still fall within the scope of the present application.

Claims

1. A solution to the problem of edge lifting in TBR all-steel tire precursors, characterized in that, The method comprises the following steps: determining the material structure of the bead portion and the difference between the flat width of the green tire and the width of the forming drum when the wear-resistant rubber bead is located at the inner end point of the bead portion; if the material structure of the bead portion and / or the difference do not meet the standard, adjusting to the standard, tracking whether the wear-resistant rubber bead appears at the inner end point of the bead portion after the adjustment, and if not, the problem is solved; if the problem still exists, adjusting the tackiness of the sidewall rubber and the tackiness of the air barrier layer to the standard value.

2. A method for solving the edge lifting problem of TBR all-steel tire precursors according to claim 1, characterized in that, The material structure of the bead portion refers to the distance between the outer end point of the sidewall rubber and the outer end point of the wear-resistant rubber, and the distance between the outer end point of the sidewall rubber and the outer end point of the wear-resistant rubber is the horizontal distance between the outer end point of the sidewall rubber and the outer end point of the wear-resistant rubber. The adjustment of the material structure of the bead portion to the standard refers to the adjustment of the distance between the outer end point of the sidewall rubber and the outer end point of the wear-resistant rubber to the standard value of the distance.

3. A method according to claim 2, characterized in that, The method for determining the standard value of the distance between the outer end point of the sidewall rubber and the outer end point of the wear-resistant rubber is as follows: The distance between the inner and outer end points of the sidewall rubber is divided into multiple gradients, a fitting line graph is drawn, and the best distance between the inner and outer end points of the sidewall rubber is obtained through regression analysis. The distance between the outer end point of the sidewall rubber and the outer end point of the wear-resistant rubber corresponding to the best distance is the standard value of the distance between the outer end point of the sidewall rubber and the outer end point of the wear-resistant rubber.

4. The method according to claim 3, characterized in that, The distance between the inner and outer end points of the sidewall rubber is 110mm-130mm, and each gradient interval is 4mm.

5. The method according to claim 3, wherein the TBR all-steel tire blank edge curl solution is characterized by, The best distance between the inner and outer end points of the sidewall rubber is 125mm±2mm, and the standard value of the distance between the outer end point of the sidewall rubber and the outer end point of the wear-resistant rubber is 15mm±2mm.

6. A method of preventing the edge lifting of a TBR all-steel tire blank wear resistant rubber according to claim 1, characterized in that, The flat width of the green tire is the distance between the two steel wire beads in the green tire, and the standard value of the difference between the flat width of the green tire and the width of the forming drum is 85mm-88mm.

7. A method for solving the edge lifting problem of TBR all-steel tire precursors, according to claim 1, characterized in that, The method for determining the standard value of the tackiness of the sidewall rubber and the standard value of the tackiness of the air barrier layer is as follows: The tackiness of the air barrier layer and the tackiness of the sidewall rubber are divided into multiple gradients respectively; DOE experiments are carried out to verify the significance of the influence of the tackiness of the air barrier layer and the tackiness of the sidewall rubber on the wear-resistant rubber bead bad rate; The best combination parameters of the tackiness of the air barrier layer and the tackiness of the sidewall rubber are obtained through the DOE experiment response optimizer combined with regression analysis, that is, the standard value of the tackiness of the sidewall rubber and the standard value of the tackiness of the air barrier layer are obtained.

8. A method according to claim 7, characterized in that, The tackiness of the air barrier layer is 6N-9N, and the tackiness of the sidewall rubber is 6N-8N, and each gradient interval is 0.5N.

9. A method for solving the edge lifting problem of TBR all-steel tire precursors according to claim 7, characterized in that, The standard value of the tackiness of the sidewall rubber is 7N±0.3N, and the standard value of the tackiness of the air barrier layer is 8.5N±0.3N.

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