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71.
探讨了确定轮胎全部材料热生成率的简化条件。在应变于一个周期内按正弦波形变化、材料的粘弹性按线性处理、橡胶的生热性能按各向同性处理、忽略橡胶-骨架增强材料垂直于帘线方向应变分量的作用等简化条件下,测定了165R15轿车子午线轮胎所用各种材料在不同使用条件下的热生成率,为轮胎温度场的计算提供了材料生热特性。 相似文献
72.
聚氨酯轮胎研发的最新进展 总被引:1,自引:0,他引:1
介绍国内外聚氨酯轮胎的研究和应用进展,对我公司聚氨酯轮胎发展历程及性能进行了详细的回顾及分析,并展望了未来聚氨酯轮胎的发展趋势以及应用前景。 相似文献
73.
74.
废旧轮眙回收利用现状和利用途径 总被引:10,自引:0,他引:10
针对废旧轮胎回收处理压力越来越大的难题,系统地分析了处理废旧轮胎的各种方法,对我国翻新轮胎,胶粉用于建筑市场、铺路建设,废胎直接用于热能市场等等的利与弊、现状与前景都做了较详细的论述。对废胎利用与管理上必要的立法问题对照国外先进国家的经验,提出了建设性的意见。 相似文献
75.
介绍了橡胶计算机辅助设计10系统(RCAD10系统)及其在新产品10-15农机具轮胎设计中的应用,并与传统设计方法进行了比较。比较结果:用RCAD10系统设计,机头宽度窄8mm,胎面胶用量少04kg,且新产品设计周期从7d缩短至1d。 相似文献
76.
Jung-Hsiu Wu 《Cement and Concrete Research》2003,33(2):245-253
Epcat, one of the spent fluid catalytic cracking (FCC) catalysts from oil-cracking refineries, shows pozzolanic activity. In this study, pastes and mortars with Epcat were prepared and cured, and their compressive strengths after 3, 7 and 28 curing days were measured. The water/binder (W/B) ratios were 0.2, 0.25 and 0.3, and the replacement levels of cement by Epcat were 0, 5, 10 and 15 wt.%. Proper amount of superplasticizer was added into each mix to ensure similar workability.The results indicate that the presence of Epcat would increase the compressive strength of mortars substantially, but increase the compressive strength of the related pastes only slightly. Epcat mortars with W/B=0.25 show more strength-enhancing effect than those with W/B=0.3, and this effect increases with the catalyst content. Therefore, the mix (W/B=0.25) incorporated 15% Epcat exhibits the greatest compressive strength (92.3 MPa). For mortars with W/B=0.2, the strength-enhancing effect occurs only for those containing 5% catalyst; this effect becomes unclear when mixes containing 10% Epcat or more because high dosage of superplasticizer was added in obtaining proper workability and that affects the strength development. The improvement in the mechanical properties of mortars is attributed to the increase in the hydrated cement paste itself and, more importantly, improved bonds between the cement paste and aggregate. 相似文献
77.
提出一种新的确定高层级轮胎内外各层帘布裁断角度的方法。根据各层帘布在成品胎内部的材料分布图和在成型机头上的材料分布图,计算该层所在的机头宽度,比较计算的机头宽度和实际的机头宽度,通过调整帘布裁断角度使两者近似相等。以此确定各层帘布的裁断角度,达到内外层帘线均匀伸张的目的。 相似文献
78.
介绍轻型载重轮胎的优化设计。采取的主要措施是:减小轮胎外缘尺寸,外直径由808mm减至798mm,断面宽由198mm减至195mm;胎面花纹以纵向花纹为主,肩部为纵横结合花纹并加深肩部通挖花纹沟的深度,改善肩部生热;胎体帘布采用加粗减层的方法,用6层1870dtex/2尼龙帘布代替8层1400dtex/2帘布。优化轮胎重量减轻4kg,轮胎性能符合国家标准。 相似文献
79.
Waste ground rubber tire (WGRT) is a complex composite containing various elastomers, carbon black, zinc oxide, stearic acid, processing oils, and other curatives. Most of the waste ground rubber tire is composed of mainly natural rubber (NR) and styrene butadiene rubber (SBR) in varying proportions. Blending it with other thermoplastic materials is difficult due to the inherent thermodynamic incompatibility. But, the compatibility can be increased by making the reactive sites in WGRT with suitable chemicals under optimum condition of shearing inside a twin screw extruder and it is said to undergo a dynamic reaction inside the extruder. To understand the mechanism of dynamic reaction process of a rubber/polyolefin blend, the blending of a truck tire model material rubber with polyolefin was first tried before it was applied to waste WGRT material. It was observed that the blends of a truck tire model rubber material and PP thermoplastic are physical mixture of two incompatible polymers in which a continuous plastic phase is largely responsible for the tensile properties. The rubber particles are the dispersed phase. The large particle size and the poor adhesion of these rubber particles are believed to be liable for the poor tensile properties. In case of blends of truck tire model material with isotactic polypropylene the tensile properties are found to be lower than that of its PP‐g‐MA counterpart which can be attributed to the reaction of the MA with the carbon black particles. A schematic representation of the possible interactions has been proposed. The effect of addition of compatibilizers such as SEBS and SEBS‐g‐MA has also been studied. The tensile and TGA studies indicate that the polarity of SEBS and SEBS‐g‐MA induces an increase in the performance characteristics for both types of polyolefins but the intensity of this increase is higher in the PP‐g‐MA based blends. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 106: 3193–3208, 2007 相似文献
80.