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.

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.

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 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.

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。

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。

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。

裂解炭黑G685在全钢载重子午线轮胎过渡层胶中的应用研究

研究裂解炭黑G685在全钢载重子午线轮胎过渡层胶中的应用。结果表明:与炭黑N660相比,裂解炭黑G685粒径小,结构度高,硫含量高,但其所含硫主要为结合硫;将裂解炭黑G685替代炭黑N660用于轮胎过渡层胶,胶料的t90延长,交联密度、定伸应力、拉伸强度和生热降低,拉断伸长率增大;在过渡层胶中用裂解炭黑G685替代50%的炭黑N660,成品轮胎的耐久性能和高速性能提高。

转鼓尺寸对工程机械子午线轮胎耐久性能影响的仿真研究

以445/95R25全钢工程机械子午线轮胎为例,建立工程机械子午线轮胎三维模型,通过橡胶材料应力和应变测试数据拟合而确定最佳的橡胶材料本构模型为Yeoh模型,进行转鼓尺寸对轮胎耐久性能影响的仿真研究。结果表明:在相同充气压力和负荷下,随着转鼓直径的增大,轮胎下沉量减小,与转鼓接触面积增大,周向接触压力分布更均匀,从而使得轮胎肩部应变能密度、Mises应力和剪切应变极值减小;当转鼓直径超过10 m时,转鼓直径对轮胎与转鼓接触特性和轮胎力学性能的影响效应显著降低;转鼓直径从1.7 m增大到3 m时,轮胎肩部应变能密度减小5%,测试的轮胎耐久寿命延长约20%。

带束层角度与经线密度对轿车子午线轮胎动态性能的影响

在有限元仿真结果与试验结果具有较高相关性的前提下,采用单一变量法,探究轿车子午线轮胎(简称轮胎)的带束层角度与经线密度对其稳态滚动阻力(简称滚动阻力)和侧偏特性的影响。结果表明:与带束层经线密度相比,带束层角度变化更能影响轮胎的动态性能;带束层角度变化对轮胎的侧偏刚性和回正刚性影响较大,对滚动阻力影响较小;轮胎的动态性能随带束层角度与经线密度的变化与轮胎的规格相关。

带束层角度与经线密度对轿车子午线轮胎静态性能的影响

在下沉量和接地印痕有限元仿真结果与试验结果具有高相关性的前提下,采用单一变量法,探究轿车子午线轮胎(简称轮胎)带束层角度与经线密度变化对其下沉量、接地印痕、径向刚性及横向刚性类静态性能的影响。结果表明:与带束层经线密度相比,带束层角度变化对轮胎的下沉量、接地印痕和刚性影响较大;轮胎的径向刚性和横向刚性随带束层角度的增大呈减小趋势;轮胎的静态性能随带束层角度变化的趋势还受轮胎的扁平率影响。

结构设计因素对半钢子午线轮胎噪声的影响

试验研究结构设计因素对半钢子午线轮胎噪声的影响。结果表明:降低三角胶高度、在一定范围内增大带束层角度和选择合适的带束层材料可在保持良好性能的前提下降低轮胎噪声。本研究可为半钢子午线轮胎结构设计提供一定参考。

轮胎钢丝帘线拉伸性能缺陷分析及质量控制对策

随着社会经济发展,汽车数量日益增多,社会各界和汽车使用者对汽车性能的要求日益提高,必须对汽车轮胎制造的质量引起高度重视,其中包括对轮胎钢丝帘线拉伸性能的分析,确保汽车制造安全质量性能得到进一步改善。本文针对子午线轮胎胎体帘线在生产过程中出现的拉伸性缺陷进行了概括,分析了缺陷产生的原因,进行了相关案例分析,并提出了相关质量把控对策。

385/65R22.5 24PR 164J AM211宽基子午线轮胎耐久性能的提高

从骨架材料、胎肩垫胶、胎面和带束层宽度等方面入手,结合有限元仿真技术进行提高385/65R22.5 24PR164J AM211宽基子午线轮胎耐久性能的研究。在骨架材料保持不变的基础上,对胎面肩部口型进行优化设计,合理配置带束层宽度,使轮胎的耐久性能提高了30%。

4×0.38UT钢丝帘线在半钢子午线轮胎带束层中的应用

研究4×0.38UT钢丝帘线替代2+7×0.28HT钢丝帘线用于半钢子午线轮胎带束层中的应用效果。结果表明,在生产工艺不变的情况下,采用4×0.38UT钢丝帘线的成品轮胎各项性能与替代前相当,轮胎质量减小,成本降低,具有较好的经济效益。

全钢载重子午线轮胎胎冠全息气泡的原因分析与解决措施

分析全钢载重子午线轮胎胎冠全息气泡的产生原因,并提出相应的解决措施。成品轮胎胎冠全息气泡产生于带束层之间及胎面与带束层之间,主要原因是半成品粘性波动,滚压轨迹不合理会加剧此病象产生。通过调整胶料粘性以及优化成型装备结构和压合轨迹,基本可以解决此类问题。

奇耐^(®)N9在全钢载重子午线轮胎胎面胶中的应用

研究奇耐^(®)N9在全钢载重子午线轮胎胎面胶中的应用。结果表明:在胎面胶生产配方中添加2份奇耐^(®)N9,胶料的密度增大,物理性能相当,但气孔率明显下降,工艺性能改善。采用试验胶料制备的315/80R22.520PR全钢载重子午线轮胎的耐久性能和高速性能与生产轮胎没有明显差异,生产成本降低。