【作者】 徐高春；

【导师】 胡庆夕；

【作者基本信息】 上海大学 ， 机械制造及其自动化， 2011， 博士

【摘要】 在现代化进程中,由于经济的快速发展导致了“资源过度消耗,环境严重污染”,不可持续发展的模式已经引起包括我国在内的国际社会的严重关注。为此,国家中长期科技发展规划明确指出,必须加快转变经济增长方式,把节约资源作为基本国策,发展循环经济,保护生态环境,加快建设资源节约、环境友好型社会,促进经济发展与人口、资源、环境相协调,实现可持续发展。本文在国家创新基金及宁波市产学研重点攻关项目的资助下,结合企业实际需求,以多工位全自动冷镦机为研究对象,通过分析冷镦工艺机理,进行了冷镦机绿色环保设计,对其中的关键部件进行了重点研究,特别对降低油雾形成及回用处理方面展开了探索性的研究和设计工作。本文从金属变形理论出发,分析冷镦工艺机理及材料成形过程,研究多工位冷镦机的动作及结构原理,以绿色设计的“源头预防结合末端治理”为策略,提出了冷镦机总体绿色设计方案,包括冷镦机关键部件的节材优化设计、润滑冷却系统绿色设计、油雾处理方法及处理流程等。为了从“源头预防”污染产生,分析冷镦机工况下的油雾源,对润滑冷却系统提出了冷却效果更高、耗油量低、产生油雾最少的冷却方式,创新性地把低温油气喷雾射流冷却技术应用于冷镦模具的润滑冷却系统中,设计了低温油气喷雾射流润滑冷却系统,其临界热流密度是浇注冷却和低温冷风射流的1.5倍和7倍以上,换热系数相当于浇注润滑冷却和低温冷风射流的2倍和15倍以上,而低温喷雾射流的流量仅为0.18kg/min,相当于目前浇注润滑冷却(10kg/min)的1/500,以如此小的消耗量,即可达到很好的润滑冷却效果,充分体现了节能高效润滑冷却方式的换热优势;在喷嘴优化设计方面,根据Laval原理,设计出具有过渡流道型线的新型跨音速喷嘴,同时根据冷风喷雾原理和冷镦机实际工况,设计了润滑冷却控制系统。为了避免冷镦加工时产生的高浓度油雾积聚易引发明火造成火灾的情况,根据企业和行业要求,本文设计的油雾处理装置改变了传统的电控方法,应用空气动力学原理,重点研究以少量人工能诱导激发自然能的机理,实现人工能放大效应和节能;针对冷镦机油雾处理,应用工程流体力学的控制方程以及相关的数值模拟方法,建立了三相油雾流体在特定流场中的气体动力学模型及其流动规律,采用混合模型方法对冷镦机定模上方的油雾抽吸状态进行数值模拟,对冷镦机油雾处理收集箱的油雾多相流流动采用随机轨道模型方法进行数值模拟,掌握了控制体内的压力分布、温度分布、周期初始阶段混合相分布、速度矢量、流线等特性,为确立油雾处理器的设计有效性提供了理论依据和直观的仿真结果;分析了油雾弥散速度及抽吸口安置高度对油雾抽吸性能的影响以及油雾进口和压缩冷气流进口位置对油雾分离的影响。在综合流体分析和优化设计基础上,制作了油雾处理器物理样机。此外,论文以绿色设计为原则,通过对不同冷却方式的换热效果以及对喷雾冷却的试验结果分析,验证采用低温油气喷雾射流是解决冷镦机模具润滑冷却的有效设计方法;采用科学评分评价法对油雾处理器设计中的抽吸装置和油雾分离方法进行了方案评价,验证了采用空气放大器为最佳抽吸装置设计方案以及采用惯性分离法与过滤法相结合的油雾最佳分离方法。经对油雾处理器现场测试结果分析,表明本文研制样机的新颖性和有效性。本文将绿色环保设计的理念运用到全自动冷镦机产品的设计中,在分析研究和设计制造的基础上,获得了多项有关绿色设计和油雾处理等国家发明专利及实用新型专利,为解决冷镦机行业的清洁化生产和降低碳排放作了较深入的理论研究和实际工作。更多还原

【Abstract】 Ones yearn for better life in big industry time whose center is working for living at full efforts and in modern time ones pursue better and higher efficiency for profits to be maximized while in post modernization time or say re-modernization ones go to higher level whose center represents the respect for natural lives and chases the most happiness. However, during evolution from modernization to post modernization, rapid development of economy results in resource over-exhausted and environment seriously-polluted. This situation of unsustainable development has been concerned for international society including China. So the mid-long-term project of Chinese science development indicate clearly that China has to follow scientific outlook on development and to speed up to change the mode of economic increasing, i.e., take saving resource as basic national strategy, develop circle economy, protect ecological environment, accelerate building resource-saving and friendly-environment society, and promote coordinating of economy development with population, resource and environment, and realize sustainable development.Funded by the National Innovation Fund and production-study-research key project of Ningbo City, combined with the actual needs of enterprises, this paper takes automatic cold heading machine as the research object, analyzes its process mechanism, checks some stages with non-conformance post-modernization manufacturing concept, discusses the total research scheme of green design, and researches key components deeply, in particular, carries out exploratory work in the formation of oil mist and its reuse of processing.From metal deformation theory, this paper elaborates the mechanism of cold forging and forming process of parts, analyzes kinematic and structural principles of cold heading machine with multi-stations. Based on post-modernization manufacturing theory and taking green design as the strategy, this paper poses total research scheme of green design of cold heading machine, including design rules of lubricant cooling system, green design scheme, the basic ideas and processes of oil mist treatment, while establishes parametric model and master control box model for oil mist treatment of automatic cold heading machine with multi-positions.To protect generating of pollution from beginning, in lubricating and cooling technology of cold heading machine, the low-temperature spray jet cooling technology is innovatively used in lubricant cooling system of cold forging die. Based on the concept of green design, low-temperature spray jet technology in lubrication and cooling system was designed. The critical heat-flow density of the system is 1.5 times of pouring cooling and over 7 times of low-temperature and cool-wind jet flow, and the exchange-heat coefficience is 2 times of pouring lubrication cooling and over 15 times of low-temperature and cool-wind jet flow. The flux of the system is only 0.18kg/min, which is correspond to 1/500 of that for present pouring lubrication cooling, i.e., 10kg/min. It fully incamates the advantage of heat exchanging of saving energy and high-efficient lubricating cooling for such a small energy consumption to reach so good lubricating cooling effects. In the optimal design of the nozzle, referenced the principle of Laval, a new transonic nozzle with transition channel type is designed. Based on both the theory of cold spray jet and the real operating conditions of cold heading machine, lubricating and cooling control system is designed.Generating lots of oil mist during cold heading process disobeys the principle of post-modernization manufacturing. Also, to avoid high concentrations of oil mist easily lead to a fire, according to the requirements of enterprise and industry, the device of oil mist treatment designed in this paper does not use the traditional electric control method, while applying aerodynamic principle. The study concentrates on the mechanism by using a small amount of artificial energy induced excitation of natural energy, realizing the amplification effect of artificial energy and energy conservation. Aiming at oil mist treatment in cold heading machine, applying control equations in engineering fluid dynamics and related numerical simulation methods, based on the basic ideas and processes of oil mist treatment, it is established for gas dynamics model and flow pattern of three-phase mist flow of fluid in a particular field. The state of oil mist suction at the top of cover die of the cold heading machine is numerically simulated by mixed model approach and multiphase flow of oil mist in master box by random orbit model method to gain pressure distribution chart, temperature distribution chart, distribution chart of initial mixed-phase of a cycle, velocity vectors chart, flow path chart of control volume and so on. The paper also analyzes the influence of dispersion velocity of the oil mist and height of puffs on pumping oil mist and the influence of the inlet position of oil mist and compressed air flow on oil mist separation. Based on comprehensive analysis and optimal design, the physical prototype of oil mist treatment device is made.In addition, based on the theory of green design, this paper poses evaluation index system of green design in lubricating and cooling system of cold heading machine and evaluation system model of green design for this system is established. Through analyzing and concluding the effect of transfer heat of different cooling methods(low temperature cool-air、casting and cold nebulization) as well as analyzing results of spray cooling, it is verified that cold spray jet is an effective cooling design method to solve lubricating and cooling of dies in cold heading machine. Also applying a scientific evaluation, suction devices and the method of oil mist separation in the processor design of oil mist are estimated and optimized. So air amplifier is the best design method in all the suction devices and the method of inertial separation combined with filtration is the best.This paper applies the concept of green design under post-modernization to products design of automatic cold heading machines. Based on the above analysis and design, several national invention and utility patents related to green design and oil mist treatment have been applied. And deeper theoretical study and practical work to solve the clean production in cold heading machine industry and reduce carbon emissions have been done.更多还原