本科毕业设计(论文)通过答辩
摘 要
冲压工艺分析主要考虑产品的冲压成形工艺,最主要的是包括经济和技术两方面内容。在经济方面,主要根据冲压件的生产批量,分析产品成本,阐明采用冲压生产可以取得的经济效益;在技术方面,根据产品图纸,主要分析零件的结构特点、尺寸大小、精度要求和材料性能等因素是否符合冲压工艺的要求。因此工艺分析,主要是讨论在不影响零件使用的前提下,能否使零件以最简单最经济的方法冲压出来。
由于产品没有特殊要求,故模具结构采用冲孔、落料的工序设计,并采用正装方式设计模具结构,即凹模装在下模部分。由于料不厚,冲压速度较快,卸料采用刚性卸料结构。废料和产品均采用在凹模(下模)向下推出。因本冲裁件生产批量大故采用条料。。
在冲压零件中,材料费用占60%以上,排样的目的就在于合理利用原材料,因此材料的利用率是决定产品成本的重要因素,必须认真计算,确保排样相对合理,以达到较好的材料利用率。
冲压是高效的生产方式,采用复合模,尤其是多工位的级进模,可在一台压力机上完成多道冲压工序,实现由带料开卷、矫平、冲裁到成形、精整的全自动生产。生产效率高,
关键词:冲压工艺;排样;模具结构;级进模
本科毕业设计(论文)通过答辩
Abstract
Stamping process analysis mainly consider product stamping forming process, the main is including two aspects of economic and technical content. On the economic front, mainly
according to the stamping parts of the production batch, analyzing the product cost, clarify the stamping production can achieve economic benefit; In terms of technology, according to the product drawings, analysis the main parts of structure, size, accuracy requirements and materials performance factors such as whether accord with the requirement of stamping process. Process analysis, therefore, is mainly discussed in does not affect the parts use premise, can make the easiest and most economical way to stamping out.
Because the product has no special requirements, so the mold structure with punching and blanking process design, and USES the way of dress design of mould structure, namely the
female die is installed in the mould parts. Because the material is not thick, stamping speed faster, discharging discharging using rigid structures. Waste materials and products are used in the die (mould) down. Production batch die blanking pieces for this article using the material.
In stamping parts, material costs accounted for more than 60%, the purpose of the layout is reasonable use of raw materials, so the utilization rate of materials is an important factor to
decide the product cost, must be calculated carefully, to ensure that the line sheet for reasonable, in order to achieve a better material utilization.
Stamping is efficient production mode, adopting the composite die, especially the multi-station progressive die, stamping can be completed in a pressure on the multichannel working procedure, to achieve the pick-up uncoiling, leveling, cutting to the forming and
finishing automatic production. High production efficiency, good working conditions production cost is low, general can produce hundreds of pieces per minute.
Key words: Stamping process;Layout ;The mould structure ; Progressive die
II
本科毕业设计(论文)通过答辩
目 录
摘 要 .............................................................................................................................................. I Abstract .......................................................................................................................................... II 目 录 ............................................................................................................................................ V 1 绪论 ............................................................................................................................................. 1 1.1 本课题的研究内容和意义 .................................................................................................. 1 1.2 国内外的发展概况 .............................................................................................................. 2 1.3 本课题应达到的要求 .......................................................................................................... 5 2 冲压工艺设计 ............................................................................................................................. 6 2.1 冲压件简介 .......................................................................................................................... 6 2.2 冲压的工艺性分析 .............................................................................................................. 6 2.3 冲压工序 .............................................................................................................................. 7 2.4冲裁间隙 ............................................................................................................................... 8 2.5 冲压工艺方案的确定 .......................................................................................................... 8 3 支撑板连续模设计 ..................................................................................................................... 9 3.1 模具结构 .............................................................................................................................. 9 3.2 确定其搭边值 ...................................................................................................................... 9 3.3 确定排样图 ........................................................................................................................ 10 3.4 材料利用率计算 ................................................................................................................ 11 3.5 凸、凹模刃口尺寸的确定 ................................................................................................ 11 3.5.1落料部份凸、凹模刃口尺寸的确定 ........................................................................... 11 3.5.2冲两圆孔及异性孔的凸、凹模刃口尺寸的计算 ....................................................... 13 3.6 冲压力计算 ........................................................................................................................ 14 3.6.1 落料部分冲压力 .......................................................................................................... 15 3.6.2 冲2个圆孔部分冲压力 .............................................................................................. 15 3.6.3 冲两个异形孔部分冲压力 .......................................................................................... 16 3.6.4 总冲压力 ...................................................................................................................... 16 3.7压力机选用 ......................................................................................................................... 16 3.8 压力中心计算 .................................................................................................................... 17 3.9 模具主要零部件的结构设计 ............................................................................................ 18 3.9.1 凹模结构及设计 .......................................................................................................... 18 3.9.2 冲两小圆形孔及异形孔的凸模设计 .......................................................................... 19 3.9.3 落料凸模设计 .............................................................................................................. 21 3.9.4 卸料板设计 .................................................................................................................. 22 3.9.5 凸模固定板设计 .......................................................................................................... 23 3.9.6 凸模垫板设计 .............................................................................................................. 24 3.10 标准件确定 ...................................................................................................................... 25 3.10.1 模架确定 .................................................................................................................... 25
V
本科毕业设计(论文)通过答辩
3.10.2 上模螺钉确定 ............................................................................................................ 26 3.10.3 上模销确定 ................................................................................................................ 26 3.10.4 下模螺钉确定 ............................................................................................................ 26 3.10.5 下模销确定 ................................................................................................................ 26 3.10.6 卸料螺钉确定 ............................................................................................................ 26 3.10.7模柄确定 ..................................................................................................................... 26 3.10.8模柄上止转销的确定 ................................................................................................. 27 3.11 模具闭合高度、校验压力机 .......................................................................................... 27 4 结论与展望 ............................................................................................................................... 28 4.1 结论 .................................................................................................................................... 28 4.2 不足之处及未来展望 ........................................................................................................ 28 致 谢 ........................................................................................................................................... 29 参考文献 ....................................................................................................................................... 30
VI
本科毕业设计(论文)通过答辩
1 绪论
1.1 本课题的研究内容和意义
模具,是工业生产的基础工艺装备,在电子、汽车、电机、电器、仪表、家电和通讯等产品中,60%~80%的零部件都依靠模具成形,模具质量的高低决定着产品的质量高低,所以,模具被称之为“百业之母”。模具又是“效益放大器”,用模具生产的最终产品的价值,往往是模具本身价值的几十倍乃至上百倍。
采用模具生产零部件,具有生产效率高、质量好、成本低、节约能源和原材料等一系列优点,用模具生产制件所具备的高精度、高复杂程度、高一致性、高生产率和低消耗,是其他加工制造方法所不能比拟的。已成为当代工业生产的重要手段和工艺发展方向。现代经济的基础工业。现代工业品的发展和技术水平的提高,很大程度上取决于模具工业的发展水平,因此模具工业对国民经济和社会发展将起越来越大的作用。
我国模具工业的技术水平近年来也取得了长足的进步。大型、精密、复杂、高效和长寿命的模具上了一个新台阶。大型复杂冲模以汽车覆盖件模具为代表,已经能生产部分新型轿车的覆盖件模具。体现高水平制造技术的多工位级进模的覆盖面,已从电机、电器铁芯片模具,发展到接插件、电子枪零件、空调器散热片等多种家电零件模具。在大型塑料模具方面,已能生产电视的塑壳模具、大容量洗衣机全套塑料模具,以及汽车保险杠、整体仪表板等模具。在精密塑料模具方面,已能生产相机塑料模具、多型腔小模数齿轮模具及塑封模具等。在大型精密复杂压铸模方面,目前,国内已能生产自动扶梯整体踏板压铸模及汽车后桥齿轮箱压铸模。其他类型的模具,例如子午线轮胎活络模具、铝合金和塑料门窗异型材挤出模等模具,也都达到了较高的水平,并可以替代进口模具。
具经过行业结构调整后,将呈现十大发展趋势:一是模具的精度将更加精密;二是模具日趋大型化;三是多功能复合模具将进一步发展;四是热流道模具在塑料模具中的比重将逐渐增大;五是模具标准化和模具标准件的应用将日渐广泛;六是气辅模具及适应高压注射成型等工艺的模具将有较大发展;七是快速经济模具的前景十分广阔,八是压铸模的比重将不断提高,同时对压铸模的寿命和复杂程度也将提出越来越高的要求;九是塑料模具的比例将不断增大;十是模具技术水平将不断提高,中高档模具比例将不断增大,这也是产品结构调整所导致的模具市场未来的趋势。
冲压件的生产过程一般都是从原材料剪切下料开始,经过各种冲压工序和其它必要的辅助工序加工出图纸所要求的零件,进行冲压模具设计与制造就是根据已有的生产条件,综合考虑影响生产顺利进行的各方面因素,合理安排零件的生产工序,优化确定各工艺参数的大小和变化范围,合理设计模具结构,正确选择模具加工方法,选用机床设备等,使零件的整个生产达到优质、高产、低耗、安全的目的。
由于冲压加工的零件种类繁多,各类零件的形状、尺寸和精度要求又各不相同,因而生产中采用的冲压工艺方法也是多种多样的。概括起来,可分为分离工序和成形工序两大类;分离工序是指使坯料沿一定的轮廓线分离而获得一定形状、尺寸和断面质量的冲压(俗称冲裁件)的工序;成形工序是指使坯料在不破裂的条件下产生塑性变形而获得一定形状和尺寸的冲压件的工序。
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