Finite Element Simulation of Radial Tire Building and Shaping Processes Using an Elasto-Viscoplastic Model

The comprehensive tire building and shaping processes are investigated through the finite element method(FEM)in this article.The mechanical properties of the uncured rubber from different tire components are investigated through cyclic loading-unloading experiments under different strain rates.Based on the experiments,an elastoviscoplastic constitutive model is adopted to describe themechanical behaviors of the uncured rubber.The distinct mechanical properties,including the stress level,hysteresis and residual strain,of the uncured rubber can all be well characterized.The whole tire building process(including component winding,rubber bladder inflation,component stitching and carcass band folding-back)and the shaping process are simulated using this constitutive model.The simulated green tire profile is in good agreement with the actual profile obtained through 3D scanning.The deformation and stress of the rubber components and the cord reinforcements during production can be obtained fromthe FE simulation,which is helpful for judging the rationality of the tire construction design.Finally,the influence of the parameter“drum width”is investigated,and the simulated result is found to be consistent with the experimental observations,which verifies the effectiveness of the simulation.The established simulation strategy provides some guiding significance for the improvement of tire design parameters and the elimination of tire production defects.

Tread Wear and Footprint Geometrical Characters of Truck Bus Radial Tires

Wear and mileage performance are the foremost performances for truck bus radial (TBR) tires. There are a lot of researches about the tire wear performance as well as the contact patch phenomenon by using finite element analysis (FEA) method or testing. But there is little published data on the correlations between the footprint geometry and the tread wear performance of tires. In this paper, an experiment on tire-ground performance of TBR tires is carried out by using Tekscan. The real-time changes of contact-area pressure distribution that occurred during the process of continuous load and unload are recorded. Three types of tires that act differently in behavior under normal usage are analyzed. A new method of researching in tire tread wear, which focuses on the geometrical characters of the footprint, is put forward. The experimental results of the three tires are described by using footprint geometrical characters. On the basis of studying the changing laws of footprint geometrical characters during the loading process and considering consumer survey and factory feedback information, the correlations between the geometrical character of footprints and tread destruction form are built. The analyzed results show that a greater contact area coefficient and a steady coefficient of contact result in a better wear performance for TBR tires. The footprint-shape coefficient changing laws in the process of loading are found to have a very good coincidence with the tread wear of the three types of tires. Tires with a smaller footprint-shape coefficient are likely to have an average tread wear while avoiding the shoulder wear first. The proposed research provides a new solution to predict tire-ground performance at the point of footprint and several useful references for improving tire design.

New Method for Monitoring Tire Pressure of Cars Based on the Tire Radial Deformation

Monitoring tire pressure of cars and signaling abnormal conditions is an important means to prevent deadly accidents. Large achievements have been gained, especially in direct tire pressure monitoring system（TPMS）. But there has been rarely research on indirect TPMS in the world. In China, the research on indirect TPMS is almost lacking. The international research on the indirect monitoring tire pressure method is mainly based on measuring and comparing the rotating speed of wheels. But it is very difficult to measure wheel rotating speed accurately because of the influence of many random factors. In this paper, the authors propose a new method in which the tire pressure can be monitored indirectly. This method can be used for tire calibration, wheel speed frequency standardization, wheel speed frequency comparison, and abnormal tire pressure determination. The pulse frequencies from wheel speed sensors of ABS are used to indicate tire deformation. Because the frequency has a relationship with tire deformation, the tire deformation reflects the tire pressure. Small sample statistics is used in the new method to increase the accuracy, and the experimental samples using the principle of the new method have been made and tested. The result of vehicle tests on road demonstrates that the method is efficient and accurate to monitor tire pressure. The research has positive potential for developing products.

Prediction of Deformation and Footprint of High-speed Rotating Radial Tires

In this research,the tire deformations due to rotation are divided into three parts:tread,belt and carcass.Tread deformation is obtained by using a rotating hollow cylinder model,belt expansion is calculated according to the laminated composite shell theory,and a formula of dynamic equilibrium profile is built to investigate carcass deformation.Moreover,a simple method is used to predict the footprint changes caused by tire deformation.Results show that a large deformation is occurring at tire shoulder,a smaller one at tread centre,and the shoulder deformations are mostly caused by carcass.Length of footprint side edges increase with tire rolling speed increasing.The predicted tread,belt,carcass deformations and footprint changes are in good agreement with finite element analysis results.The proposed method and the results will offer a helpful guidance to tire and vehicle engineers.

Prediction of Burst Pressure of a Radial Truck Tire Using Finite Element Analysis

This paper is concerned with the numerical prediction of the burst pressure of a radial truck tire. Even though relatively rare, the tire fracture or failure brings up a big accident. Especially, the tire burst or rupture is a rapid loss of inflation pressure of a truck and bus tire leading to an explosion. The tire burst pressure, under this extreme loading condition, can be predicted by identifying the pressure at which the cord breaking force of the composite materials is attained. Recently, the use of finite element analysis in tire optimal design has become widely popular. In order to determine the burst pressure of a radial truck tire, an axisymmetric finite element model has been developed using a commercial finite element code with rebar element. The numerical result shows that the bead wire among the various layers modeled the rebar element breaks off first in the radial truck tire. The finite element modeling with the rebar element on the bead wire of a radial truck tire is able to well predict the tire burst pressure identifying the pressure at which the breaking force of steel bead wires is reached. The model predictions of tire burst pressure should be correlated with test data, in which case the tire is hydro-tested to destruction. The effect of the design change with the different bead structure on the tire burst pressure is discussed.

Computation of rolling resistance caused by rubber hysteresis of truck radial tire

Applying the results of stress and strain calculated by 3D finite element model of truck radial tire 11.00R20, a MATLAB program used to compute rolling resistance of the tire caused by hysteresis rolling resistance (HRR) is worked out. The HRR distribution on different part of tire section, and the effects of speed, load, internal pressure and the width of the rim on HRR are analyzed. The analysis results showed that energy loss produced by tread rubber contributes the most part to HRR of the whole tire, and that to decrease the HRR, the hysteresis factor of the tread rubber should be reduced, and the distribution of the stress and strain on the section be optimized.

Basic Properties of Pyrolysis Carbon Black of Waste Tyres and Application of Pyrolysis Carbon Black in Transition Layer Rubber of All Steel Radial Tire

The main chemical composition of pyrolysis carbon black of waste tires is C,O,Cu,Zn and so on.The content of ash and fine powder in pyrolysis carbon black is high,and the 300%elongation stress is high.The difference between pyrolysis carbon black and furnace black N326,which is commonly used in rubber,is obvious compared with chemical property.The pyrolysis carbon black was used to replace furnace black N326 in the transition layer of all steel load Radial tire rubber through experimental study.It was found that the compression heat generation and dynamic loss(Tanδ)of the blend rubber before and after aging were obviously reduced,the elongation at break and resilience increased,while the tensile stress and tear strength decreased by 100%and 300%,but the hardness and tensile strength changed little before and after aging.According to the latest raw material price calculation,15 used tire pyrolysis carbon black instead of furnace carbon black N326 used in all steel Radial tire transition layer rubber application,excluding labor costs,electricity and equipment depreciation,a ton of blended rubber saves about$22.86 in production costs.

Prediction of Restriction Width of Carcass by Belts for Radial Tires :Theory, Experiment and Simulation

The restriction width of carcass by the belts( RWCB) as an important parameter of radial tire design has been neglected for a long time. In order to improve the accuracy and efficiency of tire profile design,the calculating method of RWCB is proposed. The equilibrium profile is calculated by geometric model and variational approach,based on it,the predicted model of RWCB is developed for tire design. Finally,four different designs of 12R22.5 tires are investigated by experiment and finite element method,which is used to validate the accuracy of the theoretical method. Results indicate that experimental and finite element analysis results are found to be in good agreement with theoretical results; linear relationships are existed between the cord length and RWCB,and also existed between the position of belt and RWCB; tires designed by the methods have smaller and more uniform displacement,so the method can be used for tire optimized design.

Design and Selection of Servomotor for Radial Aircraft Tire Secondary Molding Machine

The company Meridian Air Tire using two method molding,molding machine transmission components design selection using mitsubishi J4 series servo motor and control system.Among them,the two-segment host pitch and rotary servo motor selection is the most typical,this paper on its design ideas and selection of a detailed discussion,for manufacturers to correctly select servo motor to provide reference.

国产溶聚丁苯橡胶在半钢子午线轮胎胎面胶中的应用

研究国产溶聚丁苯橡胶(SSBR)在半钢子午线轮胎胎面胶中的应用。结果表明:与进口SSBR胶料相比,国产SSBR胶料的硫化特性、物理性能和耐臭氧老化性能相当;成品轮胎的高速性能和耐久性能均通过测试,滚动阻力相当,干地和湿地制动性能可满足使用要求,且可降低材料成本。

苯酚-甲醛树脂MK-95在轿车子午线轮胎胎体胶中的应用

研究苯酚-甲醛树脂MK-95(简称MK-95)在轿车子午线轮胎胎体胶中的应用。结果表明:MK-95不含游离间苯二酚和其他添加剂,其软化点和挥发分含量低于间苯二酚-甲醛树脂;在胎体胶中以MK-95等量替代间苯二酚-甲醛树脂,胶料的硫化特性、物理性能、动态力学性能和粘合性能相当,成品轮胎的高速、耐久和路试性能均达到要求。

全钢工程机械子午线轮胎胎里露线的原因分析及解决措施

分析全钢工程机械子午线轮胎胎里露线的原因,并提出解决措施。通过采取确保成型机平宽与带束层贴合鼓周长合理、缠绕机挤出胶条尺寸稳定、成型鼓扇形块周长一致、防止垫胶贴合偏歪、内衬层接头压实、合理设定硫化定型压力等措施,有效解决了胎里露线问题。

生物基白炭黑和生物基油在全钢载重子午线轮胎胎面胶中的应用

研究生物基白炭黑和生物基油在全钢载重子午线轮胎胎面胶中的应用。结果表明:使用生物基油等量代替环烷油,胶料的硫化速度略加快,300%定伸应力降低,耐切割、耐低温和耐迁移性能提高,生热略增大,耐磨性能基本相当;在同样采用生物基油的情况下,使用生物基白炭黑等量代替沉淀法白炭黑,胶料的硫化特性、生热、耐磨和耐切割性能相当,但耐疲劳性能明显降低。

高驱动性能315/80R22.5无内胎全钢载重子午线轮胎的设计

介绍高驱动性能315/80R22.5无内胎全钢载重子午线轮胎的设计。结构设计:外直径1093 mm,断面宽314 mm,行驶面宽度275 mm,行驶面弧度高7.5857 mm,胎圈着合直径570.5 mm,胎圈着合宽度240.8 mm,断面水平轴位置(H_(1)/H_(2))0.91,胎面采用泥地+雪地花纹,花纹深度24 mm,花纹饱和度66.41%,花纹周节数54。施工设计:采用双复合胎面,1^(#)和2^(#)带束层采用0.37+6×0.32ST钢丝帘线,0°带束层由3根3×0.7×0.20HE钢丝帘线压延成的冠带条围绕2#带束层缠绕而成,3#带束层采用5×5.30HI钢丝帘线,胎体采用0.22+6+11×0.205ST钢丝帘线,采用一次法成型机成型、双模蒸锅式硫化机硫化。成品轮胎性能试验结果表明,轮胎的充气外缘尺寸、强度性能、耐久性能和胎圈耐久性能均满足相应设计和标准要求。

14.00R24NHS港口专用全钢工程机械子午线轮胎的设计

介绍14.00R24NHS港口专用全钢工程机械子午线轮胎的设计。结构设计:外直径1410 mm,断面宽368 mm,行驶面宽度320 mm,行驶面弧度高20 mm,胎圈着合宽度274 mm,胎圈着合直径610 mm,断面水平轴位置(H1/H2)0.7391,胎面采用块状花纹,花纹深度64 mm,花纹饱和度72.2%,花纹周节数28。施工设计:胎面采用3层结构,胎体采用3+9+15×0.225ST钢丝帘线,带束层采用4层结构,其中1^(#)带束层采用3+9+15×0.175+0.15HT钢丝帘线,2^(#)和3^(#)带束层采用3+9+15×0.220+0.15HT钢丝帘线,4^(#)带束层采用3×7×0.20HE钢丝帘线,采用一次法两鼓/三鼓成型机成型,采用蒸锅式硫化机硫化。成品性能试验结果表明,成品轮胎的充气外缘尺寸、物理性能和静负荷性能均达到国家标准及相应设计要求。

基于高分辨率网络的全钢子午线轮胎钢丝圈区域边界分割

针对全钢子午线轮胎中纹理复杂、结构多变的钢丝圈区域边界分割困难的问题,提出一种基于高分辨率网络的轮胎钢丝圈区域边界分割方法;根据垂直投影曲线信息实现轮胎X射线衍射图像各区域的划分;利用直方图均衡化提高图像的明暗对比度,增强纹理信息;根据高分辨率网络输出的热图,基于自适应阈值方法进行边界分析,通过计算热图不同区域的阈值得到对应的二值图,统计热图中边界区域面积并筛除过小的部分,根据剩余区域重构热图并利用边界上下文信息填补被筛除的位置,从而得到整体边界分布均匀、精细的热图;在自建数据集上测试所提出方法的检测性能,通过消融实验探讨所提出的方法及其优化模块对最终边界分割结果的影响,并将所提出的方法与2种常用方法进行定量和定性对比。结果表明,钢丝圈区域的包布、反包边界分割准确率分别达到98.94%、97.23%,相对于2种常用方法,所提出的方法具有较强的稳健性和适用性。

225/45R17 ALL CLIMATE AC-1高性能全天候子午线轮胎设计

介绍225/45R17 ALL CLIMATE AC-1高性能全天候子午线轮胎设计。结构设计:外直径633 mm,断面宽度241 mm,行驶面宽度189 mm,行驶面弧度高6.6 mm,胎圈着合直径434 mm,胎圈着合宽度220 mm,断面水平轴位置(H_(1)/H_(2))1.08,胎面采用3条沟槽设计,仿生V形互锁式花纹,花纹深度7.4 mm,花纹饱和度70.07%,花纹周节数61。施工设计:采用双层胎面设计,采用2层带束层+1层冠带层设计,1^(#)和2^(#)带束层采用3×0.28ST钢丝帘线,冠带层采用锦纶66帘布,胎体采用1层1440dtex/2-115聚酯帘布,采用成型机成型、液压硫化机硫化。成品性能试验结果表明,轮胎的充气外缘尺寸、强度性能、低气压耐久性能和高速性能均满足设计要求。

新型弧形板簧支撑非充气轮胎的有限元分析

设计一种以弧形等厚板簧为主要承载部件的新型非充气轮胎,建立其有限元模型,仿真模拟静态径向加载与稳态纯滚动工况,得出轮胎径向刚度和径向力,对接地压力参数进行评价,计算出轮胎有效滚动半径。结果表明:在静态径向加载条件下,轮胎径向力与径向位移近似线性正相关,径向刚度和径向力随板簧厚度增大而增大;轮胎接地印痕中心出现应力集中现象,板簧越厚则平均接地压力越大,胎面不均匀磨损程度越高;轮胎有效滚动半径随径向负荷增大线性减小。本研究可为非充气轮胎性能分析或者结构优化提供参考。

改进YOLOv7的子午线轮胎X光图像缺陷检测

为了实现轮胎缺陷的自动检测,提高轮胎缺陷检测的精度,提出了一种子午线轮胎缺陷检测方法(YOLOv7-DCA)。首先,基于协调注意力和空洞卷积设计了DCA-MP(dilated coordinated attention-max pooling)模块,加强下采样的感受野,同时提高缺陷所占权重,提高缺陷检测精度;其次,在Neck层中融合了CARAFE(content aware reassembly of features)模块进一步提高缺陷检测精度。实验结果表明,YOLOv7-DCA模型平均检测精度可以达到97.77%,相比于原YOLO(you only look once)算法提高了3.27%。与当前主流的Faster-RCNN,YOLOv5,YOLOv7-tiny系列模型相比,综合表现效果最好。可见,该模型对于轮胎缺陷自动检测研究提供了参考意义。

全钢载重子午线轮胎胎圈露线的原因分析及解决措施

从产品设计和工艺控制方面分析全钢载重子午线轮胎胎圈露线的原因,并提出相应的解决措施。通过适当增大成型平面宽和鼓肩宽,适当减小钢丝圈内侧胎侧厚度和胎趾角度,严格控制胎侧成型定位、胎坯存放、硫化机机械手精度、钢丝圈缠绕工艺及存放等措施,有效地解决了全钢载重子午线轮胎胎圈露线问题,提高了轮胎的安全性能,降低了生产成本。