偏心轴车削加工工艺 机械系毕业论文.doc

偏心轴车削加工工艺 目录 摘要····································································3 第一章 绪论······························································4 第二章 工艺规程设计······················································5 2.1确定毛坯的制造形成····················································5 2.2基准的选择····························································6 2.2.1粗基准的选择····················································6 2.2.2经基准的选择····················································6 2.3车刀的选择····························································7 2.4制定工艺路线··························································8 2.4.1表面加工方法选择················································8 2.4.2加工顺序安排····················································8 2.5确定切削用量··························································9 结论····································································10 参考文献································································11 摘 要 关键词　偏心轴 加工工艺 加工效率 偏心轴类零件是常见的典型零件之一。按轴类零件结构形式不同，一般可分为光轴偏心、阶梯轴偏心和异形偏心轴等；或分为实心偏心轴、空心偏心轴等。它们在机器中同样用来支承齿轮、带轮等传动零件，以传递转矩或运动。 台阶偏心轴的加工工艺较为典型，反映了偏心轴类零件的大部分内容与基本规律下面就介绍一种偏心轴常用的加工工艺。 第1章 绪论 章.1确定毛坯的制造形成 机械加工工艺过程的制定是机械制造工艺学的基本内容之一，生产过程是指将原料转变为成品的全过程，制定工艺规程的要求是在保证产品质量的前提下尽量提高生产率和降低成本，同时还应利用国内外先进技术和经验并保证良好的劳动条件，制定工艺规程的步骤的首要目标就是确定毛坏，包括选择类型及其制造方法，即毛坯的制造形成。 零件机械加工的工序数量，材料消耗和劳动量，在很大程度上与毛坯有关，毛坯的形状和尺寸越接近成品零件，即毛坯精度越高，则零件的机料加工劳动量越少，材料消耗也少，机械加工的生产率可提高，成本可降低，但是毛坯制造费用高了，因此，确定毛坯要从机械加工和毛坯制造两个方面综合考虑，以求取体效果，毛坯类型有铸、锻、压制、冲压、焊接、型材和板材等。确定毛坯时要考虑如下因素:1、零件材料及其力学性能。当零件的材料选定后，毛坯的类型就大致确定了，例如:材料是铸铁，就是铸造成毛坯;材料是钢材，且力学性能要求高时，可选锻件，当力学性能要求较低时，可选型材或铸钢，2、零件的形状和尺寸。形状复杂的毛坯，常采用铸造方法，薄臂零件不可用砂型铸造，尺寸大的铸件宜用砂型铸造，中、小型零件可用较先进的铸造方法。常见一般用途的钢质阶梯轴零件。如各台阶的直径构差不大，可用棒料如各台阶的直径相差较大，宜用锻件。尺寸大的零件因受设备限制一般用自由锻。3、生产类型，大量生产应选精度和生产率都比较高的毛坯制造方法，用于毛坯制造的昂贵费用，可由材料消耗的减少和机械加工费用的降低来补尝，单件小批生产则应采用木模手工造型或自由锻。4、具体生产条件，确定毛坯必须结合具体生产条件，如现场毛坯制造的实际水平和能力处协的可能性等，有条件时，应积极组织地区专业化生产，统一供应毛坯。5、充分考虑利用新工艺，新技术和新材料的可能性，例如精铸、精锻、冷轧、冷挤压、粉未冶金和工程材料等。在机械中的应用日益广泛，应用这些方法后，可大大减少机械加工量，有现出时甚至可不再进行机械加工，其经济效果非常显著 2.2基准的选