外文翻译--发动机塑料进气歧管的应用与发展趋势

1 附 录 Engine plastic intake manifold application and development trend Because plastic products unique advantages, plastic intake manifold will become aluminium alloy intake manifold alternative products. Since always, as the key components, domestic engine intake manifold are using aluminum alloy products. And according to understand, foreign plastic intake manifold application in a wide range, such as BMW, modern, nissan, which upscale automobile use plastic intake manifold. According to the auto air-intake system manufacturing company a technology expert introduction, compared with traditional aluminum alloy intake manifold, plastic intake manifold weighs just for aluminum manifold 1/2, its at low speed, low load power, torque increase was can reach above 10%. Meanwhile, the airway smooth plastic intake maifold, improve the engine performance, compared with aluminium alloy manifold fuel can reduce 6% to 8%, in addition, still can improve engine performance and emission function, reduce engine noise, and with the aluminum alloy intake manifold interchangeability strong. Domestic to automotive plastics intake manifold research startting evening, plastic intake manifold manufacturing and r&d technology is still in the blank, in this field technical level is low, its market share is less than 2%. Some of the countrys auto manufacturers have to import from abroad plastic intake manifold high. A technology expert says. Changan group technology development center of a personage thinks, along with the market competition, reduce automobile manufacturing costs into the central focus of automobile enterprise, new materials, new technology products are more valued and cheap plastic intake manifold replace traditional heavy metal intake manifold become an inevitable 2 trend. Meanwhile, plastic intake manifold demand, will accompany the increases production car increases, its market prospect synchronization is nottaken lightly. In recent years, functional plastic application in automobile engine has made breakthrough progress, more and more engine components to begin using a plastic material production, especially with plastic intake manifold replace metal intake manifold has become an inevitable trend of automobile engine. With the traditional metal intake manifold, plastic intake manifold compared with what strengths? Metal intake manifold generally USES is cast iron or alloy material. In order to satisfy the engine intake and efi system installation requirements, and in manufacturing complex metal intake manifold often faced manufacturing difficulties, its yield is very difficult to guarantee. In 1990, the German BMW company USES molten core method successfully produce plastic intake manifold. Later, plastic intake manifold with its light weight, low cost, performance is good wait for a characteristic quickly replaced the gold Belong to intake manifold, become the new engine of choice. In European and American countries, about 90% of the exhaust from the opposite side of naturally aspirated engines use plastic intake manifold. Specifically, the plastic intake manifold main With four advantages: (1) in weight, because plastic intake manifold generally USES the nylon PA66 material, the proportion is about 50% of aluminum alloy material. (2) in addition, the thickness of the plastic intake manifold for 2.5 3mm commonly, and aluminum alloy intake manifold wall thickness generally greater than 4mm. Therefore, plastic intake manifold weight relative to light many, usually only for aluminum alloy around 40% of the intake manifold. (3) in power, because plastic intake manifold wall smoother, therefore to improve air filling quantity. Compared with aluminium alloy the intake manifold, engine performance can improve the 3% 5%. (4) in the economic aspect, plastic intake manifold brings good airflow, thus helping to gasoline engine cylinder in full within the engine burn, the fuel consumption and emissions 3 could have been improved obviously. (5) in cost, although the intake manifold of plastic materials used with aluminum alloy material cost basic same, but because plastic intake manifold can once moldings, forming the rate of high, while the aluminum alloy casting and into the yield of inlet manifold blank much lower, and the machining cost is relatively high, therefore plastic intake manifold production usually cost more than aluminum alloy intake manifold low 20% 35%. At present, the plastic intake manifold preferred materials are nylon. Nylon is the advantage of high temperature resistant, chemical stability, but its shortcoming is larger, the percentage of ethylene glycol resistance performance also not too good, and its water is too strong, bibulous the strength will decline after nylon nearly 40%. Therefore, the widely-spreading use increased 25% 35% of PA6 or PA66 fiberglass reinforced polyamide. Nylon before joining fiberglass, its shrinkage after obviously improved. For internal including cooling channel intake manifold, suggest using special anti glycol nylon formula. Although the world many plastic material supplier in continuously develops new intake manifold plastic materials, plastic materials in order to enhance the various performance, but nylon material is still the best choice at present. Plastic intake manifold production process Currently the world what are the main types of plastic intake manifold production technology? What are the strengths and weaknesses of each? At present more mature plastic intake manifold processing technology is mainly molten core injection molding technology and vibration friction welding technology. The two technologies have different features. (1) molten core injection technology is the earliest, the most mature used plastic intake manifold production process. Its principle is: use the low melting point of solder alloy intake manifold inner cavity, and then the core nuclear assembly into a mold, again to mold to infuse nylon. Injection molding process is completed, a by nylon molding the shapes of the intake manifold in upcoming lumen core nuclear claddings inside. At this time, with internal metal core nuclear inlet manifold into melting in the pool, to make metal core nuclear melting. Because of the metal core nuclear melting point lower (generally), and nylon 110 the melting point of relatively high, so in internal core in the process of nuclear 4 melting plastic intake manifold Shape remain unchanged. Molten core method produce plastic intake manifold advantage is: intake manifold wall complete smooth, thereby improving the gas liquidity, can maximize the engine performance； Because be once the intake manifold injection molding, good air-tightness, high-yield； Molten core process can eliminate plastic intake manifold in injection molding process produces the residual stress, making intake manifold has better mechanical properties. Molten core method shortcoming is: in the metal core nuclear fusion molten core and core process, to consume large amounts of energy, thus make molten core method the cost of producing plastic intake manifold are relatively high. (2) vibration friction welding technology is also called more pieces of welding method. When the intake manifold in design plastic complex structure, can be in the intake manifold due to relatively simple, can a structure of the injection molding, then two or more pieces of each piece by friction welder welding up, to form a complete plastic intake manifold. At present, most plastic intake manifold manufacturers are using vibration friction welding technology. Its main advantage is: high production efficiency, low cost. Its defect is the weld seams low intensity, appearance is bad, gas liquidity are relatively poor. Plastic intake manifold domestic production status Plastic intake manifold of the nationalization process can be roughly divided into three stages: The first stage for imported stage. In the early 1990s, as some of the establishment of joint venture automobile enterprises, foreign advanced product line with the engine was introduced some introduction of domestic cars. In this one phase, plastic intake manifold as engine, its core of important component technology from foreign party control, imports cost is high. The second phase is mainly for some enterprises directly in domestic production. At this stage, the foreign-capital enterprise in foreign plastic intake manifold production line and complete mould to the home, use of domestic and cheap labor, for in the domestic provide matching the webuton of plastic intake manifold, and plastic intake manifold design 5 &development work still at abroad. The third stage, with the domestic automobile manufacturing technology advances, some domestic enterprise started plastic intake manifold research and development work. Plastic intake manifold is a kind of high-tech products, including many engine aspects of key technology. But at present domestic most plastic intake manifold production enterprise past just ordinary plastic products factory, most of them do not have design and production engine technical ability, it could only be modelled some have outdated plastic intake manifold, their technical level the good and bad are intermingled. Overall, the current domestic production of plastic intake manifold ubiquitous technology level is low, and can not meet the requirements engine. 6 发动机塑料进气歧管 的应用与发展趋势 由于塑料产品特有的优点，塑料进气歧管将成为铝合金进气歧管的替代产品。 一直以来，作为发动机的关键零部件，国内的发动机进气歧管都是采用铝合金产品。而据了解，国外对塑料进气歧管的应用较为广泛，在宝马、现代、日产等高档汽车上，均使用了塑料进气歧管。 据汽车进气系统制造公司一位技术专家介绍，与传统的铝合金进气歧管比较，塑料进气歧管的重量仅为铝质歧管的 1/2，其在低速低负荷时，功率、扭矩提高幅度可达10%以上。同时，塑料件的气道光滑，提高了发动机性能，与铝合金歧管相比油耗可降低 6%8%，此外 ，还能改善发动机的动力性与排放功能，降低发动机噪声，且与铝合金进气歧管互换性强。 “ 国内对汽车塑料进气歧管的研发工作起步较晚，塑料进气歧管生产及研发技术方面尚属空白，在此领域内的技术水平较低，其市场占有率还不到 2%。国内的一些汽车生产厂家不得不从国外高价进口塑料进气歧管。 ” 一位技术专家介绍说。 长安集团技术开发中心的一位人士认为，随着市场竞争加剧，减少汽车制造成本成为整车企业关注的中心，新材料、新工艺的产品就更受重视，质优价廉的塑料进气歧管取代传统笨重的金属进气歧管成为必然趋势。同时，塑料进气歧管的需求 量，也将伴随汽车年产量的不断增加而同步增大，其市场前景不可小视。 近年来，功能性塑料在汽车发动机上的应用已取得了突破性的进展，越来越多的发动机部件开始采用塑料材料制作，尤其是用塑料进气歧管取代金属进气歧管已成为汽车发动机的必然趋势。 同传统的金属进气歧管相比，塑料进气歧管具有哪些优点？ 金属进气歧管一般采用的是铸铁或铝合金材料。为了满足发动机进气和电喷系统安装方面的要求，在制造结构复杂的金属进气歧管时常常面临着制造工艺方面的困难，其成品率很难保证。 1990 年，德国宝马公司采用熔芯法成功地生 产出塑料进气歧管。 之后，塑料进气歧管以其重量轻、成本低、性能好等特点迅速取代了金属进气歧管，成为新型发动机的首选。在欧美国家，大约有 90% 的进排气异侧的自然吸气发动机都 7 使用了塑料进气歧管。具体而言，塑料进气歧管主要 具有 4 个方面的优点： (1) 在重量方面，由于塑料进气歧管一般采用尼龙 PA66 材料，其比重约为铝合金材料的 50%。 (2)另外，塑料进气歧管的管壁厚度一般为 2.53mm，而铝合金进气歧管的壁厚一般大于 4mm。因此，塑料进气歧管的重量相对要轻很多，通常仅为铝合金进气歧管的 40%左右。 (3) 在动力性方面，由于塑料进气歧管的内壁比较光滑，因此有利于提高进气充量。与铝合金进气歧管相比，发动机的动力性可提高 3%5%。 (4)在经济性方面，塑料进气歧管能带来良好的气流，从而有助于汽油在发动机缸内的充分燃烧，使发动机的经济性和排放都能得到明显改善。 (5) 在成本方面，虽然进气歧管所使用的塑料材料与铝合金材料的成本基本相同，但由于塑料进气歧管能够一次成型，成型后的合格率高，而铸造而成的铝合金进气歧管毛坯的成品率要低很多，且其机加工费用也相对较高，因此塑料进气歧管的生产成本通常比铝合金进 气歧管低 20%35%。 目前，塑料进气歧管的首选材料是尼龙。尼龙的优点是耐高温、化学稳定性好，但其缺点是收缩率较大，耐乙二醇的性能也不太好，并且其吸水性太强，吸水后尼龙的强度会下降近 40%。因此，人们普遍使用增加了 25%35% 玻纤的 PA6 或 PA66 增强尼龙。尼龙在加入玻纤后，其收缩率得到了明显改善。对于内部含冷却水道的