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设计总说明20世纪90年代以来，全世界汽车行业都在加速发展,特别是中国,汽车产量持续增长。随着汽车普及率迅速提高，减轻车身质量、节能降耗及降低成本已成为汽车工业发展的主要目标之一。聚丙烯保险杠因其外型时尚以及市场保有量、市场需求量比较大，更重要的是享受国家节能环保补贴，所以价格上有很大优势，以及良好的生产前景。本设计的注塑产品是汽车的前后保险杠，关于改性聚丙烯保险杠原料，助剂，生产工艺，生产设备选型有详细的介绍。38713
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本设计选用聚丙烯为主要原料，EPDM是改性助剂，注塑工艺为多级注塑，注射设备为宁波海达公司生产HDX−2500T型号，以及与之配套的辅机。主要研究内容包括：汽车保险杠的作用，原料的优点，成型工艺流程，聚丙烯材料的性能及在保险杠上的应用，工艺流程的物料衡算和能量衡算，以及车间、厂房的布置等。聚丙烯材料拥有成本比较低，质量轻，耐化学性能好、成型方法简单、容易回收等特点，所以在近几年来聚丙烯在汽车上的应用剧增，已成为汽车用塑料中用量最多的品种。三元乙丙橡胶是乙烯、丙烯和少量的非共轭二烯烃的共聚物，是乙丙橡胶的一种，叫做三元乙丙橡胶的原因，因其主链是由化学稳定的饱和烃组成，只在侧链中含有不饱和双键，故其耐臭氧、耐热、耐候等耐老化性能优异，可广泛用于汽车部件、建筑用防水材料、电线电缆护套、耐热胶管、胶带、汽车密封件等领域。PP/EPDM共混体系以及以它们为基体的填充增强体系,由于优异的冲击性能及较理想的综合性能,使其步入了工程塑料的应用领域。注塑成型方法的优点是生产速度快、效率高，操作可实现自动化，品种比较多，形状可以由简到繁，尺寸可以由大到小，而且制品尺寸精确，产品易更新换代，能成形状复杂的制件，注塑成型适用于大量生产与形状复杂产品等成型加工领域。采用多级注射成型技术突破了传统的注射加保压的注射加工方式,有机地将高速与低速注射加工的优点结合起来，在注射过程中实现多级控制，可以克服注塑件的许多缺陷。多级注射成型工艺实质上是在塑料熔体向型腔充模的瞬间,实现不同注射速度的控制，使塑料熔体在充模流动中达到一种近似理想的状态。进而多级注塑有利于提高制品质量，纠正一些缺口和缺陷，多级注塑要求实现不同位置上的不同注塑压力等工艺参数的控制，适合薄壁制品，长流程的大型制品。注塑成型工艺过程主要包括填充、保压、冷却、脱模四个阶段，这四流程关系到注塑产品的质量好坏处于核心地位，且四个阶段是一个完整的连续过程。原料的预处理包括干燥、过筛、输送、称量、混合等，本设计第三章中对此进行了详细的介绍，以及各个过程选择哪种方法。接下来就是设备的选择，本设计的第四章，针对设备进行了选择，用表格的形式列出设备选择的最终结果，一目了然。在第五章，进行了物料衡算，根据物料衡算框图、过程、结果可以分析需要多少原料，每一种原料在每一个环节损失有多少。第优尔章进行能量衡算，根据能量守恒定律，结合热量传递实况可以一步一步推算出，过程中的能量损耗。在最后几个章节给出了经济衡算，生产组织结构，人员安排，轮班制班次表等一系列信息，基本完成了整个设计内容。附录为所设计的厂房设备放置图。
An annual output of 200,000 sets of car bumpers injection molding workshop process design
Gross instruction
Since the 1990s, around the world are accelerating the development of the automotive industry, especially in China, the auto output had a sustained growth in recent years. With the rapid development of the automobile, reducing the body mass, saving energy and reducing consumption and reducing the cost has become one of the main goals of the development of the automobile industry. Polypropylene bumpers for the stylish and the recoverable amount of the market, market demand is relatively large, more important is to enjoy the national energy-saving environmental protection subsidies, so prices have great advantage and good prospect for the production. The design of injection products is front and rear bumper of the car, about the modified polypropylene bumper raw material, auxiliary, production process, production equipment selection have detailed introduction. The design uses polypropylene as the main raw material, EPDM is modified additives, molding process for multi-stage injection molding, injection equipment for Ningbo Haida company production HDX - 2500t types, and matching with the auxiliary. Main research contents include: automobile bumper, advantages of raw materials, molding process, performance and application of polypropylene (PP) on the bumper, process of material balance calculation and energy balance calculation, workshop and workshop layout, etc. Polypropylene material has relatively low cost, light weight, good chemical resistance and the forming method of simple, easy to recycle the characteristics, so in in recent years to polypropylene in automotive application of surge has become automotive plastics used in most varieties. EPDM rubber is a copolymer of ethylene, propylene and a small amount of non-conjugated dienes, is a kind of ethylene propylene rubber, called EPDM (ethylene propylene diene ter monomer), because the backbone is composed of saturated hydrocarbons of chemically stable, only in the side chain containing unsaturated double bond, so the ozone resistance, heat resistance, weather resistance and other resistant aging properties, widely used in automotive parts, construction waterproofing materials, wire and cable sheathing, heat-resistant hose, adhesive tape, automobile seal etc. PP/EPDM blends and the filling enhancement system of them, due to the excellent impact and the ideal performance, has made it into the application field of engineering plastics. Injection molding method has the advantage of fast production speed, high efficiency, automation, and more varieties, shape can be from simple to complex, the size can be from small to big, and accurate product size, easy replacement, parts of complex shape, injection molding suitable for mass production with complex shape product molding field. The multi-stage injection molding technology breaks through the traditional injection coverage against the pressure of injection processing, combine organically the high-speed and low-speed injection processing advantages, in the injection process realize multilevel control can overcome many defects of injection molded parts. The essence of multi-stage injection molding technology is in the plastic melt to the instant when filling the cavity to achieve different injection velocity control, so that the plastic melt in the mold filling reach a state close to the ideal. Than multi-stage injection molding is helpful to improve the quality of the products, to correct some of the gaps and deficiencies, multi-stage injection molding required to achieve control of process parameters for different injection pressure, etc. in different position, suitable for thin-walled products, the long process of large products. The plastic injection molding process mainly includes filling, packing, cooling and demoulding four stages, the quality of the four processes related to the injection molding products in the core and four stages is a continuous integrity of the process. The raw material pretreatment includes drying, sieving, conveying, weighing and mixing, etc. This design in the third chapter of this design, and each process to choose which method. Next is the choice of equipment, the design of the fourth chapter for the device, the choice of the form of the form of the final results of the device selection, at a glance. In the fifth chapter, the material balance is carried out, according to the block diagram, the process and the results can be analyzed how much raw material, every kind of raw material in each link loss. In the sixth chapter, according to the law of conservation of energy, the energy loss of the process can be calculated by combining heat transfer. In the last few chapters, the economic equilibrium, the structure of production organization, the arrangement of personnel, the shift schedule and so on, have been accomplished the whole design.. Appendix for the design of plant equipment placement map.