摘 要 活塞是汽车发动机中的一个主要零件,承受着交变的机械负荷和热负荷,发动机中工作条件最恶劣的关键零部件之一,随着汽车整车对发动机动力性、经济性和可靠性的要求越来越严格,活塞也就更加需要具备良好的耐热性、耐磨性、导向性和密封性。为满足零件的功能,其加工质量尤为关键。
基于活塞特有的机械加工工艺特点,单靠一般的通用机床很难满足活塞的高精度要求,因此专用的设备及工艺装备在活塞切削加工中使用广泛。其功能和精度也直接影响了最终产品关键的质量指标。本论文主要是针对活塞加工的工艺规程及加工中所使用的典型专用夹具、刀具和量具的设计进行详细说明。根据活塞工作条件、结构特点以及技术要求等因素,编制了两套工艺方案,择优制定了活塞加工的工艺规程,并设计了两套关键工序中 专用设备所使用的专用夹具各一套。5128
关键词 活塞;工艺;夹具;毕业论文
Abstract
Piston is a main section of automotive engine, which endure cross-changing mechanical load and heat load. It is also one of the key parts which have the worst working environment in the engine. Piston need to have well nature of heat-resistant, wearable, oriented and airproof along with the whole auto required more and stricter about the engine’s charter of momentum,economy and reliability. the quality of processing are so important for satisfied the parts function.
Based on the technologic characters of mechanical working which belong to piston, it is difficult to satisfy the high precision demand of piston only relaying on a general common machine tool. So the special equipment and technological outfit are extensive use in piston cutting processing.The quality of the final products is also directly influenced by function and accuracy. This paper is primary aimed at technological procedure of the piston and give a detail illustration about typical special fixture, cutter and measuring implement in processing. According to piston working condition, structural trait, technological request and some factors, people weave two technological proposals. The better proposal will selected to make technological procedure of the piston, and design a special fixture, in processing of special equipment in two key procedures.
Key words piston; technology; fixture;
目 录
绪 论. 5
1 活塞的工艺分析 . 6
1.1 活塞的作用 6
1.2 活塞的特点 6
1.3 活塞的主要技术条件分析.8
1.3.1 活塞裙部外圆与气缸的配合.8
1.3.2 活塞销的要求.8
1.3.3 销孔(活塞的)的位置公差格要求.8
1.3.4 活塞重量的要求.8
2 活塞的工艺规程的设计.9
2.1 活塞的材料和毛坯的制造 ..9
2.2 定位基面的选择..11
2.3 制定工艺路线..12
2.3.1 加工方法的确定..12
2.3.2 工艺路线方案一..14
2.3.3 工艺路线方案二15
2.3.4 工艺方案的比较与分析15
2.4 机械加工余量、工序尺寸和毛坯尺寸的确定.16
2.4.1 止口的加工余量..16
2.4.2 端面及顶面的加工余量..16
2.4.3 销孔的加工余量17
2.4.4 外圆的加工余量.17
2.5 确定切削用量及基本工时.17
2.5.1 加工条件17
2.5.2 计算切削用量17
2.5.3 基本工时..17
2.6 重点工序的加工说明..18
2.6.1 止口的加工..18
2.6.2 环槽的加工..19
3 专用夹具的设计.21
3.1 车削外圆夹具的设计.22
3.1.1 工序加工要求及工艺分析..22
3.1.2 夹具定位方案的确定(定位基准、定位元件的选择..22 汽车发动机活塞零件的工艺装备设计+CAD图纸:http://www.751com.cn/jixie/lunwen_2048.html