共查询到20条相似文献,搜索用时 140 毫秒
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本文介绍了单螺杆塑料挤出机标准测试机头的用途、规格、使用范围、结构及相关测试仪表、测试方法,挤出机技术性能曲线,测试结果和曲线的处理方法及标准测试机头在新型螺杆开发方面的应用。 相似文献
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单螺杆挤出机挤出理论研究进展 总被引:2,自引:0,他引:2
潘龙;张玉霞;金志明;薛平 《中国塑料》2009,23(5):12-19
论文回顾了单螺杆挤出机挤出理论发展史,并从固体输送、熔融、熔体输送和混合四个方面详细介绍了近十年来挤出理论的最新研究进展。在指出现有不足的同时,提出了单螺杆挤出机未来的研究方向。 相似文献
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新型PVC粉料直接成型单螺杆挤出机及应用 总被引:2,自引:0,他引:2
从硬质聚氯乙烯(UPVC)型材、管材的特殊成型规律入手讨论了单螺杆挤出机在UPVC粉料直接成型时所面临的各种问题,提出了特殊设计的IKV系统、功能螺杆、可控的排气机筒、计量喂料、螺杆控温等五个有关UPVC干混粉料直接成型的关键。同时介绍了这种单螺杆挤出机在生产中的应用情况。 相似文献
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分别使用单螺杆挤出机、双螺杆挤出机、反应型挤出机挤出聚对苯二甲酸乙二酯(PET),研究其在不同挤出温度、不同螺杆转速下熔融挤出后PET的特性黏数变化情况。使用双螺杆挤出机时,PET降解最严重,特性黏数平均降低23.5%。使用单螺杆挤出机:在较低挤出温度时挤出产物基本不降解;在高温时挤出产物降解明显,挤出温度每提高10℃,产物特性黏数平均降低5.8%;较高的螺杆转速有利于防止PET的降解;原料含水量越低,PET分子越不易降解。使用反应型挤出机时,PET热降解程度大于使用单螺杆挤出机。PET最适合使用单螺杆挤出机,在较低挤出温度、较高螺杆转速、物料经过烘干的情况下进行熔融挤出加工。 相似文献
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用途广泛的双螺杆挤出机 总被引:1,自引:0,他引:1
介绍了国内外对于双螺杆挤出机研究的最新动向。在理论上,人们可以更准确地计算挤出机的重要加工参数,评价各种类型双螺杆挤出机的优劣;在实验上,反应挤出技术代表了双螺杆挤出机开发的趋势,在此基础上的多螺杆技术是该领域的新发展。 相似文献
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A novel rotation extrusion processing system was self‐designed to prepare high‐performance polyethylene (PE) pipes. In this study, during the extrusion of the PE pipes at a high mandrel rotation speed, compressed air, as a cooling medium, was introduced through their interior to achieve the quick cooling of the inner wall and the effects of the inner wall cooling rate on the microstructure and mechanical properties of the obtained PE pipes were investigated. The experimental results showed that in contrast to conventional extrusion, the molecular orientation deviated from the axial direction under a high mandrel rotation speed and was fixed by the inner wall cooling; with increasing cooling rate, the orientation degree also increased. On the other hand, cooling promoted the augmentation of spherulites. So when the cooling rate reached a certain high point, the effect of cooling on the formation of spherulites was stronger than that on the fixation of the orientation. A much higher cooling rate decreased the orientation degree, which was closely related to the performance of the PE pipe. As a result, there was an optimal cooling rate of the inner wall during the rotation extrusion for better performance of the PE pipe. When the cooling rate was 1.5°C/s, the hoop strength of the PE pipe produced by the novel extrusion method increased from the original 24.1 MPa up to 37.1 MPa without a decrease in the axial strength, and the pipe's crack initiation time increased from 27 to 70 h. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011 相似文献
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在螺杆转速高于300r/min的新型高速挤出机中,为了保证挤出制品质量,除了改进挤出机械的结构,计量段的冷却变得尤为重要。在对高速挤出过程中的计量段进行传热分析的基础上,对不同操作条件下冷卸装置的换热效果进行分析比较,为设定高速挤出过程中的计量段冷却方案找到理论依据,进而更好地控制机筒的表面温度,提高机筒内的熔体混合效果,使物料均匀挤出。 相似文献
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对三螺杆挤出机的结构、混合机理和挤出特性进行了分析,重点论述了三螺杆挤出机的研发及应用现状,并对四螺杆挤出机的研发现状进行了简要介绍,指出多螺杆挤出机发展的不足之处,对多螺杆挤出机的研究与应用具有一定的指导意义. 相似文献
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R. M. Secor 《Polymer Engineering and Science》1986,26(14):969-974
Twin-screw extruders are used very effectively, when partially filled, for mixing and surface renewal of high-viscosity fluids. The rate of energy input, often sufficiently high to be a major design consideration, determines the drive power, the heat input to the fluid, and the cooling requirements. Operating limitations may be fixed by thermal degradation of the material being processed. A simple model for the rate of energy dissipation in twin-screw extruders predicts that the power input is proportional to the square of the screw speed. Measurements were made of shaft torque and screw speed for polyisobutylene passing through a large twin-screw extruder having co-rotating shafts. The experimental procedure avoids the problems of changes in holdup and temperature that accompany changes in screw speed under steady state conditions. The power input was found to be proportional to the screw speed raised to the exponent 1.90. This result was attributed to slightly pseudoplastic behavior of the fluid in the radial clearances. 相似文献