止转垫板冷冲压工艺及其连续模设计开题报告

欢迎下载本文档参考使用，如果有疑问或者需要CAD图纸的请联系q1484406321编号无锡太湖学院毕业设计（论文）相关资料题目： 止转垫板冷冲压工艺及连续模设计 信机 系 机械工程及自动化专业学 号： 0923278 学生姓名： 刘 奎 指导教师： 钟建刚 （职称：副教授 ） （职称： ）2013年5月25日目 录一、毕业设计（论文）开题报告二、毕业设计（论文）外文资料翻译及原文三、学生“毕业论文（论文）计划、进度、检查及落实表”四、实习鉴定表无锡太湖学院毕业设计（论文）开题报告题目：止转垫板冷冲压工艺及连续模设计 信机 系 机械工程及自动化 专业学 号： 0923278 学生姓名： 刘奎 指导教师： 钟建刚 （职称：副教授） （职称： ）2012年11月20日课题来源来源于无锡海诺有限公司，是电器产品上的一个零件。科学依据（1）课题科学意义随着当今科技的发展，工业生产中模具的使用已经越来越引起人们的重视，而被大量应用到工业生产中来。冲压模具的自动送料技术也投入到实际的生产中，冲压模具可以大大的提高劳动生产效率，减轻工人负担，具有重要的技术进步意义和经济价值。现在模具生产采用了一系列高新技术，如CAD/CAE/CAM/CAPP等技术、计算机网络技术、激光技术、逆向工程和并行工程、快速成形技术及敏捷制造技术、高速加工及超精加工、微细加工、复合加工、表面处理技术等等。因此，模具工业已成为高新技术产业的一个重要组成部分。模具技术水平在很大程度上决定于人才的整体水平，而模具技术水平的高低，又决定着产品的质量、效益和新产品的开发能力，因此模具技术已成为衡量一个国家产品制造水平高低的重要标志！如今汽车、电子、电器、航空、仪表、轻工、塑料、日用品等工业部门极其依赖模具。没有模具，就没有高质量的产品。模具不是一般的工艺装备，而是技术密集型的产品，工业发达国家把模具作为机械制造方面的高科技产品来对待他们认为：“模具是发展工业的一把钥匙”；“模具是一个企业的心脏”；“模具是富裕社会的一种动力”。工业发展水平的不断提高，工业产品更新速度加快，对模具的要求越来越高，尽管改革开放以来，模具工业有了较大发展，但无论是数量还是质量仍满足不了国内市场的需要，因此，要使国民经济各个部门获得高速发展，加速实现社会主义四个现代化，就必须尽快将模具工业搞上去，从而充分发挥模具工业在国民经济中的关键作用。（2）研究状况及其发展前景我国冲压模具无论在数量上，还是在质量、技术和能力等方面都已有了很大发展，但与国外经济需求和世界先进水平相比，差距仍很大，一些大型、精度、复杂、长寿命的高档模具每年仍大量进口。近年许多模具企业加大了用于技术进步的投资力度，将技术进步视为企业发展的重要动力。一些国内模具企业已普及了二维CAD，并陆续开始使用UG、Pro/Engineer、I-DEAS、Euclid-IS等国际通用软件，个别厂家还引进了Moldflow、C-Flow、DYNAFORM、Optris和MAGMASOFT等CAE软件，并成功应用于冲压模的设计中。我国的模具正向着高新产业逐步迈进。今后模具技术的发展应该为适应模具产品“交货期短”、“精度高”、“质量好”、“价格低”的要求服务。一方面是制品使用周期短，品种更新快，另一方面制品的花样变化频繁，均要求模具的生产周期越快越好。因此，开发快速经济具越来越引起人们的重视，另外，采用计算机控制和机械手操作的快速换模装置、快速试模技术也要得到发展和提高。在未来的模具设计制造中更要全面推广CAD/CAM/CAE技术并将CAD/CAM/CAE向集成化、智能化和网络化发展。随着微机软件的发展和进步，技术培训工作也日趋简化，在普及推广模具CAD/CAM技术的过程中，应抓住机遇，重点扶持国产模具软件的开发和应用。在竞争如此激励的今天，抓住模具市场日益全球化的机遇将模具产品向大型化、精密化、多功能复合模具进一步发展。研究内容本课题要求对给定零件止板垫片进行落料、冲孔、成形连续模设计，通过对零件进行详细的冲压工艺、排样方案、模具结构分析确定零件的冲压工艺方案并制定部分零件的制造工艺，如：凸模、凹模、凸凹模、凸模固定板、垫板、凹模固定板、卸料板、导尺、挡料销、导正销等。通过该课题能够让学生掌握中等复杂程度零件冲压连续模设计与制造的一般方法，对零件冲压连续模工艺方案的制定、工艺计算及连续模具设计有了更深层次的认识。拟采取的研究方法、技术路线、实验方案及可行性分析1、到图书馆或网上查阅相关资料，查找相关书籍。对连续模深入了解2、工艺性分析，包括结构、尺寸、基准的分析计算3、工艺方案的确定，包括工序的性质、顺序及其种类组合，确定冲压设备编写冲压工艺过程卡片。4、通过对零件、排样图等具体的计算分析，检查设计是否合理。5、总装图的绘制，编制技术文件。课题完全由计算数据决定整套模具装配图及其零件图，通过对实际情况的了解，以数据为依据进行设计分析，具体的设计计算也完全可以通过查表或者书籍获得，加上对于整套设计有完整的设计思路，完全有可行性。研究计划及预期成果研究计划：2012年11月12日-2012年12月2日：按照任务书要求查阅论文相关参考资料，填写毕业设计开题报告书。2012年12月3日-2013年1月20日：机械制造实训2013年1月21日-2013年3月1日：到企业实习，了解本专业实践知识2013年3月4日-2013年3月8日：查阅与设计相关的资料不少于10篇，其中外文不少于5篇。2013年3月11日-2013年3月15日：翻译外文资料（8000-10000字符）。2013年3月18日-2013年3月22日：分析产品图、分析冲压工序、排样方案，优选确定模具冲压方案。2013年3月25日-3月29日： 确定模具结构2013年4月1日-4月5日：计算模具刃口所需的尺寸2013年4月8日-4月12日：主要零件结构设计和尺寸计算2013年4月15日-4月19日：初步绘制模具装配图2013年4月22日-4月26日：修改模具装配图2013年4月29日-5月3日：绘制模具主要零件的零件图，不少于5个2013年5月6日-5月10日：填写冲压工艺卡片等2013年5月13日-5月17日：完成设计说明书（论文）、摘要和小结2013年5月20日-5月25日：整理所有资料，打印后上交指导教师，准备答辩预期成果：1完成模具装配图：1张（A0或A1）；2零件图：主要非标准件零件图（不少于5张）；3冷冲压工艺卡片：1张；4设计说明书：1份；5翻译8000以上外文印刷字符或译出约5000左右汉字的有关技术资料或专业文献，内容要尽量结合课题。特色或创新之处1、 使用caxa，绘图方便快捷，方便改变参量，能够直接观察成形的凸凹模。2、在设计时通过三维软件进行模拟，真实的知道设计里存在的不足3、连续模相对复合模具有效率高、寿命高等优点已具备的条件和尚需解决的问题已具备的条件： 设计方案思路已经非常明确，已初步具备设计基础，工程制图与AutoCAD，机械制造工艺学，工程材料及热处理等知识，完全含盖了设计所涉及的各个方面。 能够使用相关三维软件绘制装配图及其零件图。尚需解决的问题：初次涉及连续模，所以对设计的每个环节考虑不是很周全。在设计连续模时，要准确掌握加工速度、冲材材质、冲压力、工位数、模具间隙等各种因素。对于模具里的标准件使用需也要相当注意。指导教师意见 指导教师签名：年 月 日教研室（学科组、研究所）意见 教研室主任签名： 年 月 日系意见 主管领导签名： 年 月 日英文原文 Cutting Technology and Machining OperationsBasically, in metal cutting, a sharpened wedge-shaped tool removes a rather narrow strip of metal from the surface of a ductile workpiece in the form of a severely deformed chip. The chip is a waste product that is considerably shorter than the workpiece from which it came but with a corresponding increase in thickness of the uncut chip. The geometrical shape of workpiece depends on the shape of the tool and its path during the machining operation. Most machining operations produce parts of differing geometry. If a rough cylindrical workpiece revolves about a central axis and the tool penetrates beneath its surface and travels parallel to the center of rotation, a surface of revolution is produced, and the operation is called turning. If a hollow tube is machined on the inside in a similar manner, the operation is called boring. Producing an external conical surface uniformly varying diameter is called taper turning, if the tool point travels in a path of varying radius, a contoured surface like that of a bowling pin can be produced; or, if the piece is short enough and the support is sufficiently rigid, a contoured surface could be produced by feeding a shaped tool normal to the axis of rotation. Short tapered or cylindrical surfaces could also be contour formed. Multiple-edged tools can also be used. Drilling uses a twin-edged fluted tool for holes with depths up to 5 to 10 times the drill diameter. Whether the drill turns or the workpiece rotates, relative motion between the cutting edge and the workpiece is the important factor. In milling operations a rotary cutter with a number of cutting edges engages the workpiece. Which moves slowly with respect to the cutter. Plane or contoured surfaces may be produced, depending on the geometry of the cutter and the type of feed. Horizontal or vertical axes of rotation may be used, and the feed of the workpiece may be in any of the three coordinate directions. Speeds, feeds, and depth of cut are the three major variables for economical machining. Other variables are the work and tool materials, coolant and geometry of the cutting tool. The rate of metal removal and power required for machining depend upon these variables. The depth of cut, feed, and cutting speed are machine settings that must be established in any metal-cutting operation. They all affect the forces, the power, and the rate of metal removal. They can be defined by comparing them to the needle and record of a phonograph. The cutting speed (V) is represented by the velocity of- the record surface relative to the needle in the tone arm at any instant. Feed is represented by the advance of the needle radially inward per revolution, or is the difference in position between two adjacent grooves. The depth of cut is the penetration of the needle into the record or the depth of the grooves. The basic operations performed on an engine lathe are illustrated. Those operations performed on external surfaces with a single point cutting tool are called turning. Except for drilling, reaming, and lapping, the operations on internal surfaces are also performed by a single point cutting tool. All machining operations, including turning and boring, can be classified as roughing, finishing, or semi-finishing. The objective of a roughing operation is to remove the bulk of the material as rapidly and as efficiently as possible, while leaving a small amount of material on the work-piece for the finishing operation. Finishing operations are performed to obtain the final size, shape, and surface finish on the workpiece. Sometimes a semi-finishing operation will precede the finishing operation to leave a small predetermined and uniform amount of stock on the work-piece to be removed by the finishing operation. Generally, longer workpieces are turned while supported on one or two lathe centers. Cone shaped holes, called center holes, which fit the lathe centers are drilled in the ends of the workpiece-usually along the axis of the cylindrical part. The end of the workpiece adjacent to the tailstock is always supported by a tailstock center, while the end near the headstock may be supported by a headstock center or held in a chuck. The headstock end of the workpiece may be held in a four-jaw chuck, or in a type chuck. This method holds the workpiece firmly and transfers the power to the workpiece smoothly; the additional support to the workpiece provided by the chuck lessens the tendency for chatter to occur when cutting. Precise results can be obtained with this method if care is taken to hold the workpiece accurately in the chuck. Very precise results can be obtained by supporting the workpiece between two centers. A lathe dog is clamped to the workpiece; together they are driven by a driver plate mounted on the spindle nose. One end of the Workpiece is mecained;then the workpiece can be turned around in the lathe to machine the other end. The center holes in the workpiece serve as precise locating surfaces as well as bearing surfaces to carry the weight of the workpiece and to resist the cutting forces. After the workpiece has been removed from the lathe for any reason, the center holes will accurately align the workpiece back in the lathe or in another lathe, or in a cylindrical grinding machine. The workpiece must never be held at the headstock end by both a chuck and a lathe center. While at first thought this seems like a quick method of aligning the workpiece in the chuck, this must not be done because it is not possible to press evenly with the jaws against the workpiece while it is also supported by the center. The alignment provided by the center will not be maintained and the pressure of the jaws may damage the center hole, the lathe center, and perhaps even the lathe spindle. Compensating or floating jaw chucks used almost exclusively on high production work provide an exception to the statements made above. These chucks are really work drivers and cannot be used for the same purpose as ordinary three or four-jaw chucks. While very large diameter workpieces are sometimes mounted on two centers, they are preferably held at the headstock end by faceplate jaws to obtain the smooth power transmission; moreover, large lathe dogs that are adequate to transmit the power not generally available, although they can be made as a special. Faceplate jaws are like chuck jaws except that they are mounted on a faceplate, which has less overhang from the spindle bearings than a large chuck would have. Machining as a shape-producing method is the most universally used and the most important of all manufacturing processes. Machining is a shape-producing process in which a power-driven device causes material to be removed in chip form. Most machining is done with equipment that supports both the work piece and cutting tool although in some cases portable equipment is used with unsupported workpiece. Close accuracies, good finishes. The second application for machining is based on the high accuracies and surface finishes possible. Many of the parts machined in low quantities would be produced with lower but acceptable tolerances if produced in high quantities by some other process. On the other hand, many parts are given their general shapes by some high quantity deformation process and machined only on selected surfaces where high accuracies are needed. Internal threads, for example, are seldom produced by any means other than machining and small holes in press worked parts may be machined following the press working operations.The basic tool-work relationship in cutting is adequately described by means of four factors: tool geometry, cutting speed, feed, and depth of cut. The cutting tool must be made of an appropriate material; it must be strong, tough, hard, and wear resistant. The tool s geometry characterized by planes and angles, must be correct for each cutting operation. Cutting speed is the rate at which the work surface passes by the cutting edge. It may be expressed in feet per minute. For efficient machining the cutting speed must be of a magnitude appropriate to the particular work-tool combination. In general, the harder the work material, the slower the speed. Feed is the rate at which the cutting tool advances into the workpiece. Where the workpiece or the tool rotates, feed is measured in inches per revolution. When the tool or the work reciprocates, feed is measured in inches per stroke, Generally, feed varies inversely with cutting speed for otherwise similar conditions. The depth of cut, measured inches is the distance the tool is set into the work. It is the width of the chip in turning or the thickness of the chip in a rectilinear cut. In roughing operations, the depth of cut can be larger than for finishing operations. In metal cutting operations heat is generated in the primary and secondary deformation zones and these results in a complex temperature distribution throughout the tool, workpiece and chip. A typical set of isotherms is shown in figure where it can be seen that, as could be expected, there is a very large temperature gradient throughout the width of the chip as the workpiece material is sheared in primary deformation and there is a further large temperature in the chip adjacent to the face as the chip is sheared in secondary deformation. This leads to a maximum cutting temperature a short distance up the face from the cutting edge and a small distance into the chip. Since virtually all the work done in metal cutting is converted into heat, it could be expected that factors which increase the power consumed per unit volume of metal removed will increase the cutting temperature. Thus an increase in the rake angle, all other parameters remaining constant, will reduce the power per unit volume of metal removed and the cutting temperatures will reduce. When considering increase in unreformed chip thickness and cutting speed the situation is more complex. An increase in undeformed chip thickness tends to be a scale effect where the amounts of heat which pass to the workpiece, the tool and chip remain in fixed proportions and the changes in cutting temperature tend to be small. Increase in cutting speed; however, reduce the amount of heat which passes into the workpiece and this increase the temperature rise of the chip m primary deformation. Further, the secondary deformation zone tends to be smaller and this has the effect of increasing the temperatures in this zone. Other changes in cutting parameters have virtually no effect on the power consumed per unit volume of metal removed and consequently have virtually no effect on the cutting temperatures. Since it has been shown that even small changes in cutting temperature have a significant effect on tool wear rate it is appropriate to indicate how cutting temperatures can be assessed from cutting data. The most direct and accurate method for measuring temperatures in high -speed-steel cutting tools is that of Wright &. Trent which also yields detailed information on temperature distributions in high-speed-steel cutting tools. The technique is based on the metallographic examination of sectioned high-speed-steel tools which relates microstructure changes to thermal history. Trent has described measurements of cutting temperatures and temperature distributions for high-speed-steel tools when machining a wide range of workpiece materials. This technique has been further developed by using scanning electron microscopy to study fine-scale microstructure changes arising from over tempering of the tempered martens tic matrix of various high-speed-steels. This technique has also been used to study temperature distributions in both high-speed -steel single point turning tools and twist drills. Discounting brittle fracture and edge chipping, which have already been dealt with, tool wear is basically of three types. Flank wear, crater wear, and notch wear. Flank wear occurs on both the major and the minor cutting edges. On the major cutting edge, which is responsible for bulk metal removal, these results in increased cutting forces and higher temperatures which if left unchecked can lead to vibration of the tool and workpiece and a condition where efficient cutting can no longer take place. On the minor cutting edge, which determines workpiece size and surface finish, flank wear can result in an oversized product which has poor surface finish. Under most practical cutting conditions, the tool will fail due to major flank wear before the minor flank wear is sufficiently large to result in the manufacture of an unacceptable component. Because of the stress distribution on the tool face, the frictional stress in the region of sliding contact between the chip and the face is at a maximum at the start of the sliding contact region and is zero at the end. Thus abrasive wear takes place in this region with more wear taking place adjacent to the seizure region than adjacent to the point at which the chip loses contact with the face. This result in localized pitting of the tool face some distance up the face which is usually referred to as catering and which normally has a section in the form of a circular arc. In many respects and for practical cutting conditions, crater wear is a less severe form of wear than flank wear and consequently flank wear is a more common tool failure criterion. However, since various authors have shown that the temperature on the face increases more rapidly with increasing cutting speed than the temperature on the flank, and since the rate of wear of any type is significantly affected by changes in temperature, crater wear usually occurs at high cutting speeds. At the end of the major flank wear land where the tool is in contact with the uncut workpiece surface it is common for the flank wear to be more pronounced than along the rest of the wear land. This is because of localised effects such as a hardened layer on the uncut surface caused by work hardening introduced by a previous cut, an oxide scale, and localised high temperatures resulting from the edge effect. T