硫化胶囊对全钢载重子午线轮胎质量的影响

从硫化胶囊选型及厚度和排气线设计方面分析其对全钢载重子午线轮胎质量的影响。硫化胶囊选型应根据轮胎尺寸使其直径伸张比为15%~25%、断面周长伸张比为15%~20%。硫化胶囊厚度应综合考虑硫化质量、效率和硫化胶囊使用寿命进行优化。在满足轮胎质量要求的条件下,硫化胶囊可优先选择碎石形排气线,且排气线密度应适中。     

AB型硫化胶囊使用寿命延长的措施

从硫化胶囊设计及硫化机工装配合两方面进行综合分析，提出延长AB型硫化胶囊使用寿命的有效措施。确定合理的硫化胶囊伸张值、采用光面沟槽排气花纹设计、提升硫化胶囊关键点参数与工装设计匹配性、规范操作人员安装硫化胶囊的操作、定期检查硫化设备及配件，均可延长硫化胶囊使用寿命。     

12.00-20 16PR超加厚光胎面（L-5S）工程机械轮胎设计改进

分析12．00—2016PR超加厚光胎面(L—5S)工程机械轮胎存在的成型卸胎坯困难、硫化后成品一次检验外观合格率低及充气外直径偏小等问题的产生原因，通过采取改用Φ690mm全折叠式成型机头、增大胎面下层宽度、减小帘线假定伸张值和胎冠帘线角度及增加排气线与排气孔等措施，轮胎成品外缘尺寸达到设计要求，外观一次合格率由不足60％提高至90％以上，且生产效率提高。     

B型硫化胶囊的改进设计

确定了Ｂ型硫化胶囊的脱模直径比和直径伸张值，通过增大胶囊外直径，使Ｂ型胶囊的外轮廓形状适合低断面轮胎的内轮廓形状，减少了低断面轮胎的胎里缺陷，提高了Ｂ型硫化胶囊的使用寿命。     

空气弹簧胶囊囊体帘线质量缺陷的产生原因和解决措施

分析空气弹簧胶囊囊体帘线质量缺陷的产生原因并提出相应的解决措施.指出确定合理的帘线假定伸张值、成型机头宽度和机头直径,合理设计排气孔和排气线,定期检查和更换水胎或硫化隔膜以及严格控制半成品部件尺寸,可有效克服空气弹簧胶囊囊体帘线质量缺陷.     

硫化定型参数及胶囊对轮胎成品质量的影响

研究硫化定型和胶囊的主要参数以及胶囊的存放和使用条件对轮胎成品质量的影响,并提出相应的规范操作。硫化定型的主要参数包括一次定型高度、胶囊最大拉伸高度、装胎高度、合模暂停高度和一、二次定型压力,胶囊的主要参数包括胶囊尺寸、胶囊伸张率、胶囊排气线和胶囊厚度。通过优化硫化定型参数,合理选择胶囊,规范胶囊的存放和使用条件,可以延长胶囊的使用寿命,减少轮胎成品外观质量缺陷,降低生产质量成本的损失。     

半钢子午线轮胎硫化胶囊配置方法

介绍轮胎新规格产品投产前配置硫化胶囊的方法和注意事项。胶囊的选择可采用根据轮胎轮廓重新设计胶囊,根据胶囊参数选用外购新胶囊,根据设计参数选择现有胶囊代用3种方式,通常优先选择外购新胶囊和代用现有胶囊的方法。影响硫化胶囊配置的主要因素包括胶囊形状、胶囊尺寸参数和排气线形状：对于半钢子午线轮胎,需要选择形状与轮胎轮廓接近的长筒形胶囊,其他的一般都用鼓形胶囊;胶囊纵向伸张率的推荐取值范围为15%～30%,小于10%容易出现胶囊打折或轮胎胎里窝气,大于40%胶囊的使用寿命直线下降;排气线的形状一般有斜线形、网格形和碎石形3种主要形状,在胶囊寿命稳定的条件下,优先考虑选择碎石型或网格型胶囊。     

铁道车辆空气弹簧橡胶囊外观质量问题分析

分析了铁道车辆空气弹簧橡胶囊囊体鼓泡脱层、表面缺胶和子口附近重皮裂口、子口缺胶、囊里窝气、囊里露线和囊体帘线弯曲的产生原因,并提出了相应的解决措施:严格控制半成品部件尺寸;确定合理的帘线假定伸张值、机头宽度和机头直径;合理设计排气孔和排气线;定期检查和更换水胎或硫化隔膜等。     

高温硫化半钢子午线轮胎外观质量缺陷的原因分析及解决措施

介绍高温硫化半钢子午线轮胎缺胶、气泡、胎圈宽窄不一、胎里露线和欠硫等外观质量缺陷的产生原因,并提出相应解决措施.通过采取严格控制胶料混炼温度、合理设置模具排气孔、定期清洗模具、调整成型压力和硫化定型高度、合理选取帘线假定伸张值以及定期检查和更换硫化胶囊等措施,轮胎外观质量缺陷明显减少,产品的一次合格率显著提高.     

全钢载重子午线轮胎胎里欠硫的原因分析及改善措施

分析全钢载重子午线轮胎胎里欠硫的原因,并提出相应的改善措施。通过采取根据轮胎尺寸及胶囊的直径伸张比和断面周长伸张比选择胶囊型号、增大硫化胶囊排气线的尺寸和密度、调整预定型高度和机械手装胎位置的定位精度、增大定型压力及提高胎坯定型一次合格率等措施,降低了成品轮胎胎里欠硫缺陷的发生率,提高了轮胎质量。     

国产IIR的应用研究

研究国产IIR l751在气囊、隔膜及自行车内胎中的应用效果，并与进口产品IIR268进行对比。IIRl751用于气囊和隔膜工具胶中，其半成品和成品的强伸性能均较好；用于自行车内胎中，其性能达到国家标准要求；IIRl751混炼胶的门尼粘度大于IIR268，硫化胶耐高温热老化性能和抗硫化返原能力不如IIR268，生产的气囊和隔膜在使用后期易变软，尚需改进。     

醋酸纤维素纤维干法纺丝成形模拟

建立了基于Maxwell粘弹性本构方程的干法纺丝动力学模型,对醋酸纤维素纤维干法纺丝过程进行了模拟,预测了纤维成形过程中丝条的溶剂浓度、温度、速度、张力等沿纺程的变化关系。结果表明:纤维固化成形发生在闪蒸结束后离喷丝口不远处,此后丝条溶剂含量变化很小;丝条温度在闪蒸时略低于热吹风温度,闪蒸结束后迅速上升到热吹风温度;丝条张力主要来源于空气的摩擦阻力和卷绕张力,在纺程下半段以摩擦阻力为主;提高泵供量后溶剂蒸发速率变慢,丝条温度达到热吹风温度所需时间变长,丝条固化点离喷丝头越远;闪蒸速率随纺丝液溶剂含量增高而减小,同时丝条温度升到甬道温度的时间也越长。     

降低POY条干不匀率的探讨

本文探讨了从冷却吹风条件、卷绕张力、摩擦辊与膨胀芯轴间的接触压力、卷绕往复导丝器内滑块与槽筒沟槽磨损、纺丝温度及熔体挤出量的波动等因素对条干不匀率的影响。通过加强技术管理,改变由原随机抽样为分层取样法,对卷绕所有绽位每两天进行一次条干测试。并在喷丝板下100mm处加设保温插板,以防止喷丝板面温度的波动和冷却气流的干扰。侧吹风风压由仪表指示改为U形管显示,灵敏度高且直观。试验表明最佳工艺参数为:侧吹风风速0.45—0.60m/s,在纺267dtex/36f时卷绕张力为20—25cN,接触压力(背压)120—130kPa,按此工艺参数生产,条干不匀率可由1.5%降至1.1—1.2%。     

全钢载重子午线轮胎充氮硫化工艺

通过试验建立蒸汽和氮气硫化轮胎过程中的温度场模型。对测温结果进行分析后,对B型硫化机中心机构蒸汽和氮气入口进行改进,改进后的硫化机采用氮气硫化可提高成品轮胎动平衡性能20%~30%,并节约轮胎生产过程中蒸汽、过热水、电能和维修费用,降低轮胎生产成本。     

注射法生产轮胎硫化胶囊的效果、机理与展望

注射法生产轮胎硫化胶囊，具有生产能力高，成本低等优点。胶囊注射硫化成功的关键在注射阶段；在本文中介绍几种解决注射法生产胶囊质量问题的方法。现已可自制注射胶囊硫化机。     

Novel Glass Fiber‐Reinforced Composites Having a UV and Peroxy Curable Fluoropolymer Matrix

Novel glass fiber‐reinforced composites were prepared from E‐glass fibers and perfluoropolyether (PFPE), polyurethane acrylate, and methacrylate resins. The PFPE resins were synthesized by a two‐step process and formulated with reactive acrylic diluents obtaining two compositions with different viscosity and fluorine content. These formulations were photocrosslinked by UV‐A radiation and characterized by tensile and dynamic‐mechanical properties as well as by impact resistance. The two UV cured fluoropolymer compositions are high modulus (> 1 GPa), polyphasic materials characterized by a fracture toughness higher than conventional polymer matrices, like epoxies and unsaturated polyesters. Unidirectional laminate composites were also prepared by hand lay‐up and crosslinked both photochemically and thermally. Mechanical characterization of glass fiber‐reinforced composites was carried out by tensile tests and shear adhesion measurements, showing a good fluoropolymer‐glass adhesion strength (ca. 9 MPa). Surface characterization of composites by static contact angle measurements allowed the calculation of the total surface tension γ_s according to Wu's harmonic mean approximation. Surface tension is very low (< 20 mN/m) suggesting a preferential stratification of PFPE segments at the material‐air interface.

     

A continuous catalyzer reducing furance

A Continuous Catalyzer Reducing Furnace is described, in which the Furnace consists of a rotating steel tube, the catalyst being forwarded along inside of this tube by means of a helical conveyor ribbon welded to the inside of the tube. Means are provided for feeding in the unreduced catalyzer at a predetermined rate and also for discharging the finished catalyst into oil without coming into contact with air. The flow of the reducing gas is counter-current to that of the catalyst.     

湿固化聚氨酯工业涂料的强化交联固化

MCPU清漆应用于大批量工件的涂装生产线时，通过配入少量的相对分子质量小的多元醇组分，从而适当引入-NC0／-OH交联机制，由于-NCO／-OH与原有的-NCO／H20两者双重交联机制的迭加，强化了漆膜的交联固化进程，在生产线上经过低温烘烤后，漆膜的即时性能可达到生产工艺要求，而漆膜最终亦能达到MCPU应有的优良性能。该强化交联固化技术有利于涂装工艺中节能与提高生产效率。     

Water balance and pore structure development in cementitious materials in internal curing with modified superabsorbent polymer studied by NMR

In this contribution, the water balance between modified superabsorbent polymer particles of various grain sizes and a hydrating cement matrix is studied both for ordinary and white Portland cements by means of NMR relaxometry. Different approaches for the evaluation of the experimental data are compared: inverse Laplace transforms and several multicomponent fitting models. Both evaluations provide well-comparable results with respect to the overall water quantities absorbed and re-released by the superabsorber. The experimental data indicate fast water uptake within less than 5 min after watering the superabsorber/cement mixture. The re-release of the water begins along with the onset of the hydration reaction and is finished after 1 day for superabsorber powders with a dry grain size below 125 μm and takes about 2 days for larger dry grain size. The water uptake of the superabsorber inside the cement matrix is quantified to about 2250% of its dry weight.     

Influence of hydration on the mechanical,structural, thermal,and morphological properties of cement filled epoxy composites

Different loading of Portland cement (PC) (10, 20, 30, and 40 wt%) was used to produce epoxy-based polymer concrete. The optimum loading was used to prepare another sample using hydration in presence of air circulation. The polymer concretes were characterized in terms of mechanical, thermal, structural and morphological properties. The properties showed increasing trends after cement addition. Results showed that the tensile strength of the polymer concretes were improved by 37.2%, 115.5%, 165.9%, and 40.6% for loading of 10, 20, 30, and 40 wt% cement, respectively. In addition, the flexural strength of the polymer concretes was also enhanced and found maximum (175.3% higher) in 30 wt% concrete compared to neat epoxy. Other mechanical properties of the polymer concrete were also found increasing. Moreover, decomposition temperature was raised nearly 15°C for adding 30 wt% cement which was the maximum among the other polymer concretes. For the case of hydration in presence of air circulation, the prepared composite showed the highest tensile mechanical performance with improved surface topography. From the results, it was concluded that the addition of cement into the epoxy was very effective to produce polymer concretes.