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连杆工艺工装设计【钻孔Φ65.5夹具】【7张图纸】【优秀】

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连杆工艺工装设计【钻孔Φ65.5夹具】

56页 20000字数+说明书+任务书+开题报告+机械加工工艺卡+机械工序卡+外文翻译+8张CAD图纸【详情如下】

任务书.doc

外文翻译--切削加工性.doc

机械加工工艺卡1.doc

机械工序卡2.doc

机械工艺过程卡.doc

相关资料.doc

计划周记进度检查表.xls

轴A4.dwg

连杆A3.dwg

连杆上盖A3.dwg

连杆体A2.dwg

连杆工艺工装设计【钻孔Φ65.5夹具】开题报告.doc

连杆工艺工装设计【钻孔Φ65.5夹具】说明书.doc

连杆毛坯A3.dwg

连杆钻孔Φ65.5夹具.dwg

造型.dwg


摘 要

   连杆是柴油机的主要传动件之一,本文主要论述了连杆的加工工艺及其夹具设计。连杆的尺寸精度、形状精度以及位置精度的要求都很高,而连杆的刚性比较差,容易产生变形,因此在安排工艺过程时,就需要把各主要表面的粗精加工工序分开。逐步减少加工余量、切削力及内应力的作用,并修正加工后的变形,就能最后达到零件的技术要求。

   机械加工工艺是企业上品种、上质量、上水平,加速产品更新,提高经济效益的技术保障。然而夹具又是制造系统的重要部分,工艺对夹具的要求也会提高,专用夹具、成组夹具、组合夹具和随行夹具都朝着柔性化、自动化、标准化、通用化和高效化方向发展以满足加工要求。所以对机械的加工工艺及夹具设计具有十分重要的意义。


关键词: 连杆;加工工艺;夹具设计摘 要

   连杆是柴油机的主要传动件之一,本文主要论述了连杆的加工工艺及其夹具设计。连杆的尺寸精度、形状精度以及位置精度的要求都很高,而连杆的刚性比较差,容易产生变形,因此在安排工艺过程时,就需要把各主要表面的粗精加工工序分开。逐步减少加工余量、切削力及内应力的作用,并修正加工后的变形,就能最后达到零件的技术要求。

   机械加工工艺是企业上品种、上质量、上水平,加速产品更新,提高经济效益的技术保障。然而夹具又是制造系统的重要部分,工艺对夹具的要求也会提高,专用夹具、成组夹具、组合夹具和随行夹具都朝着柔性化、自动化、标准化、通用化和高效化方向发展以满足加工要求。所以对机械的加工工艺及夹具设计具有十分重要的意义。

关键词: 连杆;加工工艺;夹具设计

目录

摘 要III

AbstractIV

绪论1

1 零件的造型2

1.1零件造型软件介绍2

1.2零件造型过程2

2 零件的分析7

2.1 零件的作用7

2.2 零件的工艺分析7

2.2.1 零件图样分析7

2.2.2 工艺分析7

3 工艺规程设计9

3.1 确定毛坯的制造形式9

3.2 定位基准的选择9

3.2.1 粗基准的选择9

3.2.2 精基准的选择10

3.3 拟定工艺路线10

3.3.1 工艺路线方案一11

3.3.2 工艺路线方案二11

3.4 工艺方案的比较与分析12

3.5 机械加工余量、工序尺寸及毛坯尺寸的确定14

3.5.1 大小头两端表面14

3.5.2 99±0.01mm的两侧面14

3.5.3 内孔Φ25mm14

3.5.4 内孔Φ50mm14

3.5.5 油孔Φ5mm14

3.5.6 油孔Φ1.5mm14

3.5.7 油孔Φ4mm15

3.5.8 油孔Φ8mm15

3.5.9 螺栓孔Φ12.22mm15

3.5.10 螺栓孔Φ13mm15

3.5.11 锪孔Φ20mm15

3.5.12 镗孔Φ58±0.05mm15

3.5.13 镗孔Φ26±0.05mm16

3.5.14 镗孔Φ65.5mm16

3.5.15 镗孔Φ29.5mm16

3.5.16 铣连杆上盖5mm×8mm斜槽16

3.5.17 铣连杆体5mm×8mm斜槽16

3.6 确定切削用量及工时定额16

4 专用夹具设计45

4.1 问题的提出45

4.2 夹具设计45

4.2.1 定位基准的选择45

4.3 切削力及夹紧力计算45

4.2.2 定位误差分析46

5 存在的问题与展望47

5.1 存在的问题47

5.2 展望47

47

毕业设计小结48

致 谢49

参考文献50


   随着机械工业的迅速发展,对产品的品种和生产率提出了越来越高的要求,使多品种,中小批生产作为机械生产的主流,为了适应机械生产的这种发展趋势,必然对机床夹具提出更高的要求。特别像换挡拨叉类不规则零件的加工还处于落后阶段。在今后的发展过程中,应大力推广使用组合夹具、尤其是成组夹具。在机床技术向高速、高效、精密、复合、智慧、环保方向发展的带动下,夹具技术正朝着高精高效模块组合通用经济方向发展。


1 零件的造型

1.1零件造型软件介绍

   柴油机连杆零件的造型选用AutoCAD2007,CAD三维造型及二维图的绘制,包括三维绘图基础、创建、编辑三维实体的布尔用算,用三维图绘制二维图,有感性的认识,较强的三维结构,方便绘制二维图。也可由二维图经过拉伸、差集、并集等命令完成三维实体造型。在三维造型过程中,应选择不同的视图来进行合理的造型,使造型过程方便、简单,提高效率。

4 专用夹具设计

   为了提高劳动生产率,保证加工质量,降低劳动强度及生产成本,需要设计专用夹具。

   在机床上用于装夹工件的装置称为机床夹具,其主要作用表现在以下几个方面。

缩短辅助时间,提高劳动生产率

   夹具的使用一般包括两个过程:其一是夹具本身在机床上的安装和调整,这个过程主要是依靠夹具自身的定向键、对刀块来快速实现,或者通过找正、试切等方法来实现,但速度稍慢;其二是被加工工件在夹具中的安装,这个过程由于采用了专用的定位装置(如V形块等),因此能迅速实现。

   2)确保并稳定加I精度,保证产品质量

   加工过程中,工件与刀具的相对位置容易得到保证,并且不受各种主观因素的影响,因而工件的加工精度稳定可靠。

   3)降低对操作工人的技术要求和工人的劳动强度

   由于多数专用夹具的夹紧装置只需厂人操纵按钮、手柄即可实现对工件的夹紧,这在很大程度上减少了工人找正和调整工件的时间与难度,或者根本不需要找正和调整,所以,这些专用夹具的使用降低了对工人的技术要求并减轻了工人的劳动强度。

   4)机床的加工范围得到扩大



内容简介:
无锡太湖学院信 机系 机械工程及自动化 专业毕 业 设 计论 文 任 务 书一、题目及专题:1、题目 连杆工艺工装设计 2、专题 二、课题来源及选题依据连杆机构的应用十分的广泛,它不仅在众多工农业机械的工程机械中得到广泛的应用,而且诸如人造卫星太阳能板的展开机构,机械手的传动机构,折叠伞的收放机构及人体假肢等也都用有连杆机构,连杆机构的共同特点是原动件的运动都要经过一个不与机架直接相接相连的中间机构才能传动从动件,故称之为连杆机构。连杆机构中的运动副一般均为低副。其运动副元素为面接触,压力较小,承载能力较大,润滑好,磨损小,加工制造容易,且连杆机构中的低副一般是几何封闭,对保证工作的可靠性有利。 三、本设计(论文或其他)应达到的要求: 阅读外文资料,翻译与所学专业或课题相关的外文文献3000字左右,语句通顺、流畅、准确; 了解连杆的工作原理; 根据加工产品具体结构和加工要求,拟定分析设备设计方案; 用绘制部分零件图,装配图; 能够熟练使用CAD,并用CAD对部分零件进行三维建模; 撰写论文,要求符合本科论文的格式要求,语言简洁、流畅、层次分明。整个毕业设计过程的技术工作要严谨、灵活、工作要有主动性,计算方法、计算的程序、计算结果、结论要正确。 四、接受任务学生: 机械97 班 姓名 祝祥竣 五、开始及完成日期:自2012年11月7日 至2013年5月25日六、设计(论文)指导(或顾问):指导教师签名 签名 签名教研室主任学科组组长研究所所长签名 系主任 签名2012年11月7日Manufacturing Engineering and TechnologyMachining1. The machinability of a material usually defined in terms of four factors: 1)、 Surface finish and integrity of the machined part; 2)、 Tool life obtained; 3)、 Force and power requirements; 4)、 Chip control. Thus, good machinability good surface finish and integrity, long tool life, and low force and power requirements. As for chip control, long and thin (stringy) cured chips, if not broken up, can severely interfere with the cutting operation by becoming entangled in the cutting zone.Because of the complex nature of cutting operations, it is difficult to establish relationships that quantitatively define the machinability of a material. In manufacturing plants, tool life and surface roughness are generally considered to be the most important factors in machinability. Although not used much any more, approximate machinability ratings are available in the example below.2. Machinability Of SteelsBecause steels are among the most important engineering materials (as noted in Chapter 5), their machinability has been studied extensively. The machinability of steels has been mainly improved by adding lead and sulfur to obtain so-called free-machining steels.Resulfurized and Rephosphorized steels. Sulfur in steels forms manganese sulfide inclusions (second-phase particles), which act as stress raisers in the primary shear zone. As a result, the chips produced break up easily and are small; this improves machinability. The size, shape, distribution, and concentration of these inclusions significantly influence machinability. Elements such as tellurium and selenium, which are both chemically similar to sulfur, act as inclusion modifiers in resulfurized steels.Phosphorus in steels has two major effects. It strengthens the ferrite, causing increased hardness. Harder steels result in better chip formation and surface finish. Note that soft steels can be difficult to machine, with built-up edge formation and poor surface finish. The second effect is that increased hardness causes the formation of short chips instead of continuous stringy ones, thereby improving machinability.Leaded Steels. A high percentage of lead in steels solidifies at the tip of manganese sulfide inclusions. In non-resulfurized grades of steel, lead takes the form of dispersed fine particles. Lead is insoluble in iron, copper, and aluminum and their alloys. Because of its low shear strength, therefore, lead acts as a solid lubricant and is smeared over the tool-chip interface during cutting. This behavior has been verified by the presence of high concentrations of lead on the tool-side face of chips when machining leaded steels.When the temperature is sufficiently high-for instance, at high cutting speeds and feeds the lead melts directly in front of the tool, acting as a liquid lubricant. In addition to this effect, lead lowers the shear stress in the primary shear zone, reducing cutting forces and power consumption. Lead can be used in every grade of steel, such as 10xx, 11xx, 12xx, 41xx, etc. Leaded steels are identified by the letter L between the second and third numerals (for example, 10L45). (Note that in stainless steels, similar use of the letter L means “low carbon,” a condition that improves their corrosion resistance.)However, because lead is a well-known toxin and a pollutant, there are serious environmental concerns about its use in steels (estimated at 4500 tons of lead consumption every year in the production of steels). Consequently, there is a continuing trend toward eliminating the use of lead in steels (lead-free steels). Bismuth and tin are now being investigated as possible substitutes for lead in steels.Calcium-Deoxidized Steels. An important development is calcium-deoxidized steels, in which oxide flakes of calcium silicates (CaSo) are formed. These flakes, in turn, reduce the strength of the secondary shear zone, decreasing tool-chip interface and wear. Temperature is correspondingly reduced. Consequently, these steels produce less crater wear, especially at high cutting speeds.Stainless Steels. Austenitic (300 series) steels are generally difficult to machine. Chatter can be a problem, necessitating machine tools with high stiffness. However, ferritic stainless steels (also 300 series) have good machinability. Martensitic (400 series) steels are abrasive, tend to form a built-up edge, and require tool materials with high hot hardness and crater-wear resistance. Precipitation-hardening stainless steels are strong and abrasive, requiring hard and abrasion-resistant tool materials.The Effects of Other Elements in Steels on Machinability. The presence of aluminum and silicon in steels is always harmful because these elements combine with oxygen to form aluminum oxide and silicates, which are hard and abrasive. These compounds increase tool wear and reduce machinability. It is essential to produce and use clean steels.Carbon and manganese have various effects on the machinability of steels, depending on their composition. Plain low-carbon steels (less than 0.15% C) can produce poor surface finish by forming a built-up edge. Cast steels are more abrasive, although their machinability is similar to that of wrought steels. Tool and die steels are very difficult to machine and usually require annealing prior to machining. Machinability of most steels is improved by cold working, which hardens the material and reduces the tendency for built-up edge formation.Other alloying elements, such as nickel, chromium, molybdenum, and vanadium, which improve the properties of steels, generally reduce machinability. The effect of boron is negligible. Gaseous elements such as hydrogen and nitrogen can have particularly detrimental effects on the properties of steel. Oxygen has been shown to have a strong effect on the aspect ratio of the manganese sulfide inclusions; the higher the oxygen content, the lower the aspect ratio and the higher the machinability.In selecting various elements to improve machinability, we should consider the possible detrimental effects of these elements on the properties and strength of the machined part in service. At elevated temperatures, for example, lead causes embrittlement of steels (liquid-metal embrittlement, hot shortness; see Section 1.4.3), although at room temperature it has no effect on mechanical properties.Sulfur can severely reduce the hot workability of steels, because of the formation of iron sulfide, unless sufficient manganese is present to prevent such formation. At room temperature, the mechanical properties of resulfurized steels depend on the orientation of the deformed manganese sulfide inclusions (anisotropy). Rephosphorized steels are significantly less ductile, and are produced solely to improve machinability.3. Machinability of Various Other Metals Aluminum is generally very easy to machine, although the softer grades tend to form a built-up edge, resulting in poor surface finish. High cutting speeds, high rake angles, and high relief angles are recommended. Wrought aluminum alloys with high silicon content and cast aluminum alloys may be abrasive; they require harder tool materials. Dimensional tolerance control may be a problem in machining aluminum, since it has a high thermal coefficient of expansion and a relatively low elastic modulus.Beryllium is similar to cast irons. Because it is more abrasive and toxic, though, it requires machining in a controlled environment.Cast gray irons are generally machinable but are. Free carbides in castings reduce their machinability and cause tool chipping or fracture, necessitating tools with high toughness. Nodular and malleable irons are machinable with hard tool materials.Cobalt-based alloys are abrasive and highly work-hardening. They require sharp, abrasion-resistant tool materials and low feeds and speeds.Wrought copper can be difficult to machine because of built-up edge formation, although cast copper alloys are easy to machine. Brasses are easy to machine, especially with the addition pf lead (leaded free-machining brass). Bronzes are more difficult to machine than brass.Magnesium is very easy to machine, with good surface finish and prolonged tool life. However care should be exercised because of its high rate of oxidation and the danger of fire (the element is pyrophoric).Molybdenum is ductile and work-hardening, so it can produce poor surface finish. Sharp tools are necessary.Nickel-based alloys are work-hardening, abrasive, and strong at high temperatures. Their machinability is similar to that of stainless steels.Tantalum is very work-hardening, ductile, and soft. It produces a poor surface finish; tool wear is high.Titanium and its alloys have poor thermal conductivity (indeed, the lowest of all metals), causing significant temperature rise and built-up edge; they can be difficult to machine.Tungsten is brittle, strong, and very abrasive, so its machinability is low, although it greatly improves at elevated temperatures.Zirconium has good machinability. It requires a coolant-type cutting fluid, however, because of the explosion and fire.4. Machinability of Various MaterialsGraphite is abrasive; it requires hard, abrasion-resistant, sharp tools.Thermoplastics generally have low thermal conductivity, low elastic modulus, and low softening temperature. Consequently, machining them requires tools with positive rake angles (to reduce cutting forces), large relief angles, small depths of cut and feed, relatively high speeds, and proper support of the workpiece. Tools should be sharp.External cooling of the cutting zone may be necessary to keep the chips from becoming “gummy” and sticking to the tools. Cooling can usually be achieved with a jet of air, vapor mist, or water-soluble oils. Residual stresses may develop during machining. To relieve these stresses, machined parts can be annealed for a period of time at temperatures ranging from to ( to ), and then cooled slowly and uniformly to room temperature.Thermosetting plastics are brittle and sensitive to thermal gradients during cutting. Their machinability is generally similar to that of thermoplastics.Because of the fibers present, reinforced plastics are very abrasive and are difficult to machine. Fiber tearing, pulling, and edge delamination are significant problems; they can lead to severe reduction in the load-carrying capacity of the component. Furthermore, machining of these materials requires careful removal of machining debris to avoid contact with and inhaling of the fibers.The machinability of ceramics has improved steadily with the development of nanoceramics and with the selection of appropriate processing parameters, such as ductile-regime cutting .Metal-matrix and ceramic-matrix composites can be difficult to machine, depending on the properties of the individual components, i.e., reinforcing or whiskers, as well as the matrix material.5. Thermally Assisted MachiningMetals and alloys that are difficult to machine at room temperature can be machined more easily at elevated temperatures. In thermally assisted machining (hot machining), the source of heata torch, induction coil, high-energy beam (such as laser or electron beam), or plasma arcis forces, (b) increased tool life, (c) use of inexpensive cutting-tool materials, (d) higher material-removal rates, and (e) reduced tendency for vibration and chatter.It may be difficult to heat and maintain a uniform temperature distribution within the workpiece. Also, the original microstructure of the workpiece may be adversely affected by elevated temperatures. Most applications of hot machining are in the turning of high-strength metals and alloys, although experiments are in progress to machine ceramics such as silicon nitride. 6. SUMMARYMachinability is usually defined in terms of surface finish, tool life, force and power requirements, and chip control. Machinability of materials depends not only on their intrinsic properties and microstructure, but also on proper selection and control of process variables. 译文:1.切削加工性一种材料的切削加工性通常从四个方面来定义:(1)、已切削部分的表面光洁度和表面完整性。(2)、刀具的寿命。(3)、切削力和切削的功率需求。(4)、切屑控制。由上述可知,好的切削加工性指的是好的表面光洁度和完整性,长的刀具寿命,低切削力和功率需求。至于切屑控制,细长而卷曲的切屑,如果没有及时清理,就会在切削区缠绕,严重影响切削工序。由于切削工序的复杂性,因此很难建立一个定量确定一种材料切削加工性的关系式。在制造厂里,刀具寿命和表面粗糙度通常被认为是切削加工性中最重要的影响因素。尽管切削性能指数使用的并不多,但基本的切削性能指数在下面的材料中仍然被使用。2.钢的切削加工性因为钢是最重要的工程材料之一(如第5章所示),所以它的切削加工性已经被广泛地研究过。通过加入铅和硫磺,可以使钢的切削加工性得到大幅度地提高。从而得到了所谓的高速切削钢。二次硫化钢和二次磷化钢 硫在钢中形成硫化锰夹杂物(第二相粒子),这些夹杂物在第一剪切区形成应力集中元。其结果是使切屑容易断开而变小,从而改善了切削加工性。这些夹杂物的大小、形状、分布和集中程度显著的影响切削加工性。化学元素如碲和硒,其化学性质与硫类似,在二次硫化钢中起杂质改性作用。钢中的磷有两个主要的作用。第一它加强铁素体,增加硬度。越硬的钢,就会对切屑的形成和表面光洁度越有利。需要注意的是软钢是很难加工的,因为软钢加工容易产生积削瘤而且表面光洁度差。第二个作用是硬度增加会引起短切屑的形成而不是连续细长的切屑的形成,因此提高切削加工性。铅钢 钢中高含量的铅在硫化锰杂质尖端析出。在非二次硫化钢中,铅呈细小而分散的颗粒。铅在铁、铜、铝和它们的合金中是不能溶解的。由于它的低抗剪强度,铅在切削时充当固体润滑剂,被涂在刀具和切屑的分界处。这一特性已经被证实-在切削加工铅钢时,在刀具横向表面的切屑上有高浓度的铅存在。当温度足够高时例如,在高的切削速度和进刀速度下铅在刀具前直接熔化,并且充当液体润滑剂。除了这个作用外,铅还可以降低第一剪切区中的剪应力,减小切削力和降低功率消耗。铅能用于各种型号的钢,例如10XX,11XX,12XX,41XX等等。铅钢由型号中第二和第三数码中的字母L识别(例如,10L45)。(需要注意的是在不锈钢中,字母L指的是低碳,这是提高不锈钢耐腐蚀性的先决条件)。然而,因为铅是众所周知的毒素和污染物,因此在钢的使用中存在着严重的环境隐患(在钢产品中每年大约有4500吨的铅消耗)。于是,消除铅在钢中使用是一个必然的趋势(无铅钢)。铋和锡现正作为最可能替代钢中铅的物质而被人们所研究。脱氧钙钢 一个重要的发展是脱氧钙钢,在脱氧钙钢中可以形成硅酸钙的氧化物片。这些片状物,可以减小第二剪切区中的应力,降低刀具和切屑分界处的摩擦和磨损。温度也相应地降低。于是,这种钢产生更小的月牙洼磨损,特别是在高速切削时更是如此。不锈钢 通常奥氏体钢很难进行切削加工。振动可能是一个问题,这必需要求机床有足够的刚度。然而,铁素体不锈钢有很好的切削加工性。马氏体钢易磨蚀,易于形成积屑瘤,并且要求刀具材料有高的热硬性和耐月牙洼磨损性。经沉淀硬化的不锈钢强度高、磨蚀性强,因此要求刀具材料硬度高而耐磨。钢中其它元素对切削加工性能的影响 钢中铝和硅元素的存在总是有害的,因为这些元素结合氧会生成氧化铝和硅酸盐,而氧化铝和硅酸盐硬度高且具有磨蚀性。这些化合物会加快刀具磨损,降低切削加工性。因此生产和使用净化钢是非常必要的。根据它们的构成,碳和锰在钢的切削加工性方面有各种不同的影响。低碳钢(少于0.15%的碳)容易形成积屑瘤而使毛坯的表面光洁度很低。铸钢的切削加工性和锻钢的大致相同,但铸钢更容易磨蚀。工具钢和模具钢很难用于切削加工,通常是在切削加工之前进行退火处理。大多数钢的切削加工性在冷加工后都有所提高,冷加工能使材料变硬而减少积屑瘤的形成。其它合金元素,例如镍、铬、钼和钒,能改善钢的特性,而通常会钢减小切削加工性。硼的影响可以忽视。气态元素比如氢和氮在钢的特性方面有特别有害的影响。氧已经被证明了在硫化锰夹杂物的纵横比方面有很强的影响。含氧量越高,纵横比越低且切削加工性越好。在选择各种元素以改善切削加工性时,我们应该考虑这些元素对已加工零件在使用中的性能和强度的不利影响。例如,当温度升高时,铅会使钢变脆,尽管其在室温下对机械性能没有影响。由于硫化铁的构成,硫元素能严重的降低钢的热加工性,除非有足够的锰元素来防止这种结构的形成。在室温下,二次硫化钢的机械性能取决于变形的硫化锰夹杂物的定位(各向异性)。二次磷化钢具有更小的延展性,被单独生成来提高切削加工性。 3. 其它不同金属的切削加工性尽管越软的材料更易于生成积屑瘤而导致
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