胎体帘布反包角度对全钢载重子午线轮胎力学性能的影响

针对全钢载重子午线轮胎胎体帘布反包工艺中反包角度出现偏差的问题,采用TYABAS软件,对11.00R20全钢载重子午线轮胎在理想与实际两种胎体帘布反包角度下的力学行为进行分析.结果表明,反包角度偏差对胎圈部位剪切应力、应变的影响较大,对胎体骨架材料应力、应变的影响不明显,而对轮胎径向剐度几乎没有影响.     

有限元在优化全钢巨型工程机械子午线轮胎胎体帘布反包高度中的应用

应用有限元技术分析全钢巨型工程机械子午线轮胎在不同胎体帘布反包高度下胎体帘布反包端点应力、应变变化情况,并利用分析结果确定最优胎体帘布反包高度。有限元分析结果表明:胎体帘布反包高度在400~530 mm范围内时,胎体帘布反包端点的应力值较小;综合考虑,胎体帘布反包高度以520 mm左右为佳。     

285/35ZR22 106XL/W低扁平比轿车子午线轮胎低气压耐久性能的改善

从轮胎结构入手,采用单一变量控制法,研究三角胶高度、三角胶硬度、胎体帘布层数、胎体帘布反包高度及冠带条缠绕方式对285/35ZR22 106XL/W低扁平比轿车子午线轮胎耐久性能的影响。结果表明:在一定范围内,三角胶高度和三角胶硬度越小,轮胎低气压耐久性能越好;与胎体采用单层2200dtex/3聚酯帘布的轮胎相比,胎体采用双层1100dtex/2聚酯帘布的轮胎低气压耐久性能更优;与胎体帘布反包至三角胶上方10 mm的轮胎相比,胎体帘布反包至带束层底部的轮胎低气压耐久性能更优;与1.5层冠带条缠绕轮胎相比,2层冠带条缠绕的轮胎低气压耐久性能更优。     

12.00R20 18PR全钢载重子午线轮胎性能改进的研究

对12.00R20 18PR全钢载重子午线轮胎性能改进进行研究。通过调整胎圈和胎体反包高度来优化胎圈部位帘布反包结构,在胎圈反包端点部位增加1层尼龙包布,在尼龙包布内端点部位增加1层胶片,优化胎面胶和胎肩垫胶配方来提高胎面胶抗撕裂性能、降低胎面胶和胎肩垫胶生热,大幅度提高了胎圈的耐久性能,延长了轮胎的使用寿命。     

帘布反包端点与胶料粘合性能的改善

针对轮胎使用中出现胎侧脱层和反包端点处帘布层脱层的问题,提出改善反包端点与胶料粘合性能的解决措施.帘布反包端点在周期性应变作用下发生胎侧脱层和反包端点处帘布层脱层问题,为此设计专用胶浆配方,在胎坯成型过程中使用该胶浆对帘布反包端点进行涂刷处理.改进后轮胎胎侧脱层和反包端点处帘布层脱层的缺陷明显减少.     

轻型载重子午线轮胎一段成型取消钢簧反包三角胶

以285/75R16轻型载重子午线轮胎为例,通过调整轮胎三角胶尺寸和形状,以及改进一段成型机反包装置,达到一段成型时不用钢簧预压三角胶,而是通过反包胶囊直接将三角胶和胎体帘布一起反包,不但提高了成型效率,而且提高了三角胶反包质量和轮胎性能。     

胎体结构对载重斜交轮胎性能的影响

以10.00-20 16PR轮胎为例,试验研究胎体结构对载重斜交轮胎性能的影响.结果表明,胎体帘布层结构相同的轮胎,随着缓冲层帘布层数的增多,轮胎的充气外缘尺寸和静负荷下变形基本无变化,强度性能提高,耐久性能降低;缓冲层帘线取大角度不能限制轮胎充气后在外直径方向上的膨胀;胎体帘布层层数增多或单根胎体帘线强力提高,轮胎的充气外缘尺寸和静负荷下变形略有减小,强度性能提高,耐久性能降低;增加缓冲层帘布层数、提高胎体帘布层帘线强力是提高轮胎强度性能既经济又有效的途径.     

航空子午线轮胎胎体正反包技术的研究

研究航空子午线轮胎胎体正反包技术。航空子午线轮胎胎体成型过程中存在胎体帘布无法自动贴合和胎圈根部打褶问题,通过采取在胎体鼓两侧增加辅助支撑、降低胎体贴合鼓的折叠比、增大指形正包器与反包胶囊之间的间隙、胶囊预充气、保证两侧指形正包器动作的同步性以及优化指形正包器的结构和增加指形片数量等措施,有效解决了问题,提高了胎体的成型质量和成型效率,同时降低了工人的劳动强度。     

高模量低收缩聚酯帘布在轻型载重子午线轮胎胎体中的应用

针对轻型载重子午线轮胎胎侧起鼓现象,进行高模量低收缩聚酯(HMLS)帘布替代改性锦纶66帘布作胎体帘布的试验研究。结果表明,采用HMLS帘布替代改性锦纶66帘布作胎体帘布,7.00R16LT12PR115/111N成品轮胎强度性能、耐久性能和高速性能均达到要求,胎侧起鼓现象明显减少,生产成本基本不变。     

芳纶复合帘布的开发生产

采用芳纶与聚酯、芳纶与锦纶66进行复合捻线,开发生产芳纶复合帘布。芳纶/聚酯和芳纶/锦纶复合帘布的粘合性能和耐疲劳性能优于芳纶,用这两种复合帘布作为轮胎的胎体骨架材料,具有较高的性价比,可以满足绿色环保轮胎的生产。     

分解炉扩径的技术改造

我厂3号回转窑(Φ4m×60m)生产线在1996年年底由SP窑(产量912t/d)改为NSP窑(产量1320t/d),预分解系统为四级旋风预热器带离线式分解炉     

乙烯酮(双乙烯酮)下游产品废水的治理技术

乙烯酮(双乙烯酮)是十分重要的化工中间体,其下游产品较多。江苏某化工厂开发生产乙烯酮(双乙烯酮)下游产品三十多个,年生产规模三万多吨,是国内以乙烯酮(双乙烯酮)为中间体生产精细化学品的综合骨干企业。针对乙烯酮(双乙烯酮)下游产品废水特点,该厂结合企业实际,开展了产品优化,结构调整,清洁生产,资源循环利用,节水降耗等工作,从源头削减了污染物的生产。同时投资二千多万元新建预处理装置三套,6000m3/d废水生化处理装置一套,使全厂乙烯酮(双乙烯酮)下游产品的废水得到了有效的治理。     

水泥水化热测定方法综述

水泥水化热是中、低热水泥和核电工程用水泥的一项关键的技术指标。全球范围内测定水泥水化热的方法有溶解法、直接法/半绝热法、等温传导量热法三种。本文总结了中、美、欧相关方法标准,对其测试原理、仪器设备、试验过程等方面进行了比对,并对其在领域的应用做了简单的概括。     

A study of miscibility of blends of polybutadienes of varying microstructure

The miscibility of various amorphous polybutadienes with mixed microstructures of 1,4 addition units (cis, 1,4 and trans 1,4) and 1,2 addition units have been investigated. The studies here involved optical transparency, differential scanning calorimetry, and small angle light scattering. It was found that a 90 percent (cis) 1, 4 addition polybutadiene was immiscible with high (91 percent) 1,2 addition polybutadiene. Reduction of the 1,2 content to 71 percent induced an upper critical solution temperature (UCST) with the cis 1,4 polymer. Polybutadienes with 50 percent and 10 percent 1,2 contents were miscible above the crystalline melting temperature of the cis 1,4 polybutadiene. Immiscibility of the 91 percent 1,2 addition polymer was also found with a 10 percent 1,2 polybutadiene. The latter polymer also exhibits an UCST with the 71 percent 1,2 polymer. The results are used to interpret the characteristics of blends of polybutadienes of varying microstructure.     

几种乙炔加压设备性能的比较

阐述并比较了几种加压设备在乙炔加压清净过程中的性能和特点。     

粉煤灰中烧失量检测的不确定度分析

以F类粉煤灰为例,详细介绍了测定粉煤灰中烧失量的步骤、计算数学模型、影响测量不确定度的因素以及各项测量不确定度分量评定,人员、设备、材料、方法、环境都是影响测量不确定的因素。     

生物油的成分分析及物性测定

以添加FeCl2的ZnCl2-KCl混合熔盐裂解纤维素和秸秆,制得生物油。采用傅立叶变换红外光谱法和气相色谱-质谱法分析生物油的成分。结果表明,生物油中成分复杂,含有氧元素、多种有机化合物,主要包括酮类、醛类、酚类及羧酸类等。测定了20～80℃生物油的密度和粘度,发现生物油的密度与温度呈较好线性关系,而生物油的粘度均大于水的粘度,且不同熔盐体系对秸秆生物油的粘度无较大影响。     

Effect of degree of deacetylation of chitosan on the kinetics of ultrasonic degradation of chitosan

The objective of the study was to explore the effect of the degree of deacetylation (DD) of the chitosan used on the degradation rate and rate constant during ultrasonic degradation. Chitin was extracted from red shrimp process waste. Four different DD chitosans were prepared from chitin by alkali deacetylation. Those chitosans were degraded by ultrasonic radiation to different molecular weights. Changes of the molecular weight were determined by light scattering, and data of molecular weight changes were used to calculate the degradation rate and rate constant. The results were as follows: The molecular weight of chitosans decreased with an increasing ultrasonication time. The curves of the molecular weight versus the ultrasonication time were broken at 1‐h treatment. The degradation rate and rate constant of sonolysis decreased with an increasing ultrasonication time. This may be because the chances of being attacked by the cavitation energy increased with an increasing molecular weight species and may be because smaller molecular weight species have shorter relaxation times and, thus, can alleviate the sonication stress easier. However, the degradation rate and rate constant of sonolysis increased with an increasing DD of the chitosan used. This may be because the flexibilitier molecules of higher DD chitosans are more susceptible to the shear force of elongation flow generated by the cavitation field or due to the bond energy difference of acetamido and β‐1,4‐glucoside linkage or hydrogen bonds. Breakage of the β‐1,4‐glucoside linkage will result in lower molecular weight and an increasing reaction rate and rate constant. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 90: 3526–3531, 2003