模具高效加工方法与工艺规程外文文献翻译、中英文翻译

模具高效加工方法与工艺规程外文文献翻译、中英文翻译
模具高效加工方法与工艺规程外文文献翻译、中英文翻译

Mold highly effective processing method and technological process

Frist,Introduction

In in modern mold formed manufacture, because the mold shape surface design is day by day complex, the free curved surface accounts for the proportion unceasingly toincrease, therefore set a higher request to the mold processing technology, namely not only should guarantee the high manufacture precision andthe surface quality, moreover must pursue the processing surfaceartistic. Along with is unceasingly thorough to the high speed processingengineering research, especially in correlation technology and so onengine bed processing, numerical control system, cutting tool system,CAD/CAM software unceasingly develops under the impetus, high speedprocesses the technology more and more many to apply to the moldmanufacture processing. The high speed processing technology has had the huge influence to themold processing craft, changed the traditional mold processing to use"anneal -> mill the processing -> heat treatment -> to rubtruncates" or "the electric spark machining -> manually polishes,polishes"and so on the complex long technical process.

But, in practice in order to enhance the mold the processing efficiency,cannot pursue the high speed processing constantly, sometimes in orderto save the production cost and the enhancement production efficiency,must use the highly effective processing method, causes part ofprocessings working procedures to be possible the high efficiency tocomplete on the ordinary engine bed. Like this requests the designer to establish the reasonable moldprocessing craft, in order to enhances the mold the processingefficiency, reduces the mold the production cost, reduces mold themanufacture cycle.

Second, mold spare part machining method

With machine-finishing method processing mold spare part when mustfully consider aspect the and so on components material, structureshape, size, precision and service life different request, uses thereasonable processing method and the craft route. Through the processing equipment guaranteed as far as possible themold spare part the processing quality, reduces the fitter to makerepairs the work load, enhances the production efficiency and reducesthe cost.

Third, mold highly effective processing technological process andstrategy formulation

1. Technological process formulation

The technological process must aim at the processing object, unifiesthis enterprise actual working condition to carry on the formulation,in the technology must be advanced, in the economy must be reasonable.

2. Numerical control processing craft strategy

1) rough machining

The mold rough machining essential target is pursues in the unit timematerial removeing rate, and is half precision work preparation workpiece geometry outline. Has been constant in the rough machiningprocess through the use overseas advanced CAD/CAM software passablebelow measure maintenance cutting condition, thus obtains the goodprocessing quality.

(1) constant cutting load; Obtains the constant cutting Level area and material removeing ratethrough the computation, causes the cutting load and cutting toolattrition speed maintenance equilibrium, enhances the cutting toollife and the processing quality;

(2) avoids suddenly changing the cutting tool to enter for thedirection;

(3) avoids the cutting tool burying the work piece.

When processes the mold cavity, should avoid the cutting tool verticalinsertion work piece under, but should use inclines the knife way, best uses the screw typeunder knife to reduce the cutting tool load; When

processes the moldcore, should as far as possible first under the knife then level cutinto the work piece from the work piece;

(4) the cutting tool cuts into, cuts when the work piece should use asfar as possible inclines the type cuts into, cuts,vertically avoids cutting into, cutting;

(5) uses climbs up the type cutting (Climb cutting) to be possible toreduce the cutting heat, reduces the cutting tool stress and the workhardening degree, improves the processing quality.

2) half precision work

The mold half precision work essential target is causes the work pieceoutline shape smoothly, surface finish remainder even, this especiallyis important regarding the tool steel mold, because it will affecttime the precision work cutting tool cutting Level area change and cuttingtool load change, thus influence cutting process stability andprecision work surface quality.

The rough machining is based on the volume model (Volume model), theprecision work is based on the face mold (Su rface model). But beforedevelops the CAD/CAM system to the components geometry description isnot continual, after because has not described in front of the roughmachining, the precision work processes the model the averageinformation, therefore the rough machining surface surplus processingremainder distribution and the great surplus processing remainder isunknown.

Therefore should fifty-fifty the precision work strategy carry on theoptimization after to guarantee half precision work the work piecesurface has the even surplus processing remainder. The optimizedprocess includes: After the rough machining the outline computation,the great surplus processing remainder computation, the biggestpermission processing remainder determination, is bigger than thebiggest permission processing remainder the district (forexample transition radius and so on scoop channel, corner is smallerthan rough machining cutting tool radius region) as well as when halfprecision work the knife heart path computation to the surplusprocessing remainder and so on.

The existing mold processes CAD/CAM software mostly to have thesurplus processing remainder analysis function, and can act accordingto the surplus processing remainder the size and the distributionsituation uses the reasonable half precision work strategy. AfterCIMATRON software provides the square corner processing (CLEAN UP) toeliminate the rough machining a surplus processing remainder biggerquoin to guarantee the following working procedure even processingremainder. The Pro/Engineer software part mill (Local milling) hasthe similar function, if the partial mill working procedure surplusprocessing remainder value and the rough machining are equal, thisworking procedure only uses a minor diameter milling cutter toeliminate the quoin which the rough machining has not cut, thencarries on half precision work again; If takes the partial mill working procedure surplus to process -odd size to take half precisionwork the surplus processing remainder, then this working procedure notonly may eliminate the quoin which the rough machining has not cut,but also may complete half precision work.

3) precision work

The mold precision work strategy is decided by the cutting tool andthe work piece contact point, but the cutting tool and the work piececontact point changes along with the processing surface curved surfaceslope and the cutting tool effective radius change. Regarding complexcurved surface processing which becomes by many curved surfacecombination, should carry on the continuous treating as far aspossible in a working procedure, but is not separately carries on theprocessing to each curved surface, reduces lifts the knife, under theknife number of times. However because processes the superficial slopechange, if only defines the processing the side to eat the knifequantity (Step over), possibly creates on the slope different surfacethe actual step of distance non-uniformity, thus influence processingquality. The CIMATRON software solution above question method is eatsthe knife quantity during the definition side, uses Clean Between Pass(to eliminate between knife residual area highly) to adjust thedistance. The Pro/Engineer software solution above question method iseats the knife quantity during the definition side, again defines

theprocessing surface residual area highly (Scallop machine). In theordinary circumstances, the precision work curved surface radius ofcurvature should be bigger than the cutting tool radius 1.5 times,evades gives the direction the suddenly transformation. In themold precision work, when each time cuts into, cuts the work piece,enters for the direction change should as far as possible use thecircular arc or the curve switches over, avoids using the straightline to switch over, maintains the cutting process the stability.

Fourth, highly effective processing example

In the modernized mold production, along with to the product functionrequest enhancement, the product internal structure also changes moreand more complex, the corresponding mold structure also must alongwith it complication.

Under elaborated uses the new design manufacture technique route inthe electric appliance box plastic mold manufacture: First and so onadvanced CAD/CAM software carries on the product using Pro/ENGINEER orCIMATRON the 3D graph design; Then the basis product characteristicdesign mold structure, produces the mold cavity entity chart and theengineering plat; Again draws up the CNC numerical control processingcraft chart in CIMATRON according to the mold cavity characteristic,draws up the numerical control processing craft route, the inputprocessing parameter, produces the cutting tool way; Finally carrieson the three dimensional processing dynamic simulation, the productionprocessing procedure, and transports to the numerical control enginebed carries on the automatic processing.

When actual processing must fix with in hexagon bolt four sides ironslabs to on, then fixes again these four sides iron slab on theplaten then.

Chart 1 electric appliance box chart

Fifth,concluding remark

The numerical control programming is in the present

CAD/CAPP/CAMsystem most can obviously display one of benefit links, it in therealization design processing automation, the enhancement processingprecision and the processing quality, reduces aspect and so on productdevelopment cycle is playing the vital role. Uses CIMATRON orPro/ENGINEER and so on advanced software carries on the threedimensional modelling, then acts according to the mold cavity thecharacteristic, the definite mold cavity, divides the modular surface,produces the mold cavity entity chart, the engineering plat, theprocessing craft chart. According to the CAM system function, from theCAPP database gain processing process craft information, carries onthe spare part processing craft route the control, the inputprocessing parameter, then establishes the cutting tool way again inCAM, carries on the three dimensional processing dynamic simulation,the production processing procedure and transports to the numericalcontrol engine bed completes the automated processing.

These processing steps are the process and the development tendencywhich the modernized mold produces, it causes the complex mold corethe production to simplify as the single machine parts numericalcontrol automation production, the complete mold design and thenumerical control processing programming process all may draw supportfrom CAD/CAM software to complete on the computer. It changed

thetraditional mold manufacture method, effectively reduced the moldmanufacture cycle, greatly improved the mold quality, the precisionand the production efficiency.

模具高效加工方法与工艺规程

一、引言

在现代模具的成形制造中,由于模具的形面设计日趋复杂,自由曲面所占比例不断增加,因此对模具加工技术提出了更高要求,即不仅应保证高的制造精度和表面质量,而且要追求加工表面的美观。随着对高速加工技术研究的不断深入,尤其在机床加工、数控系统、刀具系统、CAD/CAM软件等相关技术不断发展的推动下,高速加工技术已越来越多地应用于模具的制造加工。高速加工技术对模具加工工艺产生了巨大影响,改变了传统模具加工采用的“退火→铣削加工→热处理→磨削”或“电火花加工→手工打磨、抛光”等复杂冗长的工艺流程。

但是,在实践中为了提高模具的加工效率,不能一味地去追求高速加工,有时为了节约生产成本与提高生产效率,必须采用高效加工方法,使一部分加工工序在普通机床上就可高效率完成。这样就要求设计者编制合理的模具加工工艺,以便提高模具的加工效率,降低模具的制造成本,减少模具的制造周期。

二、模具零部件的机加工方法

用机械加工方法加工模具零部件时要充分考虑零件的材料、结构形状、尺寸、精度和使用寿命等方面的不同要求,采用合理的加工方法和工艺路线。尽可能通过加工设备来保证模具零部件的加工质量,减少钳工修配工作量,提高生产效率和降低成本。

三、模具高效加工工艺规程与策略制定

1.工艺规程制定

工艺规程必须针对加工对象,结合本企业实际生产条件进行制定,技术上要先进、经济上要合理。

2.数控加工工艺策略

1)粗加工

模具粗加工的主要目标是追求单位时间内的材料去除率,并为半精加工准备工件的几何轮廓。在粗加工过程中通过利用国外先进的CAD/CAM软件可通过以下措施保持切削条件恒定,从而获得良好的加工质量。

(1)恒定的切削载荷;

通过计算获得恒定切削层面积和材料去除率,使切削载荷与刀具磨损速率保持均衡,以提高刀具寿命和加工质量;

(2)避免突然改变刀具进给方向;

(3)避免将刀具埋入工件。如加工模具型腔时,应避免刀具垂直插入工件,而应采用倾斜下刀方式(常用倾斜角为20°~30°),最好采用螺旋式下刀以降低

刀具载荷;加工模具型芯时,应尽量先从工件外部下刀然后水平切入工件;(4)刀具切入、切出工件时应尽可能采用倾斜式(或圆弧式)切入、切出,避免垂直切入、切出;

(5)采用攀爬式切削(Climb cutting)可降低切削热,减小刀具受力和加工硬化程度,提高加工质量。

2)半精加工

模具半精加工的主要目标是使工件轮廓形状平整,表面精加工余量均匀,这对于工具钢模具尤为重要,因为它将影响精加工时刀具切削层面积的变化及刀具载荷的变化,从而影响切削过程的稳定性及精加工表面质量。

粗加工是基于体积模型(Volume model),精加工则是基于面模型(Su rface model)。而以前开发的CAD/CAM系统对零件的几何描述是不连续的,由于没有描述粗加工后、精加工前加工模型的中间信息,故粗加工表面的剩余加工余量分布及最大剩余加工余量均是未知的。

因此应对半精加工策略进行优化以保证半精加工后工件表面具有均匀的剩余加工余量。优化过程包括:粗加工后轮廓的计算、最大剩余加工余量的计算、最大允许加工余量的确定、对剩余加工余量大于最大允许加工余量的型面分区(如凹槽、拐角等过渡半径小于粗加工刀具半径的区域)以及半精加工时刀心轨迹的计算等。

现有的模具加工CAD/CAM软件大都具备剩余加工余量分析功能,并能根据剩余加工余量的大小及分布情况采用合理的半精加工策略。CIMATRON软件提供清根加工(CLEAN UP)来清除粗加工后剩余加工余量较大的角落以保证后续工序均匀的加工余量。Pro/Engineer软件的局部铣削(Local milling)具有相似的功能,如局部铣削工序的剩余加工余量取值与粗加工相等,该工序只用一把小直径铣刀来清除粗加工未切到的角落,然后再进行半精加工;如果取局部铣削工序的剩余加工余量值作为半精加工的剩余加工余量,则该工序不仅可清除粗加工未切到的角落,还可完成半精加工。

3)精加工

模具的精加工策略取决于刀具与工件的接触点,而刀具与工件的接触点随着加工表面的曲面斜率和刀具有效半径的变化而变化。对于由多个曲面组合而成的复杂曲面加工,应尽可能在一个工序中进行连续加工,而不是对各个曲面分别进行加工,以减少抬刀、下刀的次数。然而由于加工中表面斜率的变化,如果只定义加工的侧吃刀量(Step over),就可能造成在斜率不同的表面上实际步距不均匀,从而影响加工质量。CIMATRON软件解决上述问题的方法是在定义侧吃刀量的同时,使用Clean Between Pass(清除刀间残留面积高度)来调整步距。

Pro/Engineer 软件解决上述问题的方法是在定义侧吃刀量的同时,再定义加工表面残留面积高度(Scallop machine)。一般情况下,精加工曲面的曲率半径应大于刀具半径的1.5倍,以避免进给方向的突然转变。在模具的精加工中,在每次切入、切出工件时,进给方向的改变应尽量采用圆弧或曲线转接,避免采用直线转接,以保持切削过程的平稳性。

四、高效加工实例

在现代化的模具生产中,随着对产品功能要求的提高,产品内部结构也变得越来越复杂,相应的模具结构也要随之复杂化。

下面阐述了在电器盒塑料模具制造中所采用的新的设计制造工艺方法路线:首先利用Pro/ENGINEER或CIMATRON等先进的CAD/CAM软件进行产品的3D 图形设计;然后根据产品的特点设计模具结构,生成模具型腔实体图和工程图;再在CIMATRON中根据模具型腔的特点绘制CNC数控加工工艺图,拟定数控加工工艺路线,输入加工参数,生成刀具路径;最后进行三维加工动态仿真,生成加工程序,并输送到数控机床进行自动加工。

在实际加工时需用内六角螺钉将四个方铁块固定于模芯上,然后再将这四个方铁块固定在机床工作台上即可。

图1 电器盒模芯图

五、结束语

数控编程是目前CAD/CAPP/CAM系统中最能明显发挥效益的环节之一,其在实现设计加工自动化、提高加工精度和加工质量、缩短产品研制周期等方面发挥

着重要作用。采用CIMATRON或Pro/ENGINEER等先进软件进行三维建模,然后根据模具型腔的特点,确定模具型腔、分模面,生成模具型腔实体图、工程图、加工工艺图。根据CAM系统的功能,从CAPP数据库获取加工过程的工艺信息,进行零部件加工工艺路线的控制,输入加工参数,然后再在CAM中编制刀具路径,进行三维加工动态仿真,生成加工程序并输送到数控机床完成自动化加工。

这些加工步骤是现代化模具生产的过程和发展趋势,它使复杂模具型芯的生产简化为单个机械零件的数控自动化生产,全部模具设计和数控加工编程过程都可以借助CAD/CAM软件在计算机上完成。它改变了传统的模具制造手段,有效地缩短了模具制造周期,大大提高了模具的质量、精度和生产效率。

快速外文文献翻译

快速外文文献翻译 在科研过程中阅读翻译外文文献是一个非常重要的环节,许多领域高水平的文献都是外文文献,借鉴一些外文文献翻译的经验是非常必要的。由于特殊原因我翻译外文文献的机会比较多,慢慢地就发现了外文文献翻译过程中的三大利器:Google“翻译”频道、金山词霸(完整版本)和CNKI“翻译助手"。 具体操作过程如下: 1.先打开金山词霸自动取词功能,然后阅读文献; 2.遇到无法理解的长句时,可以交给Google处理,处理后的结果猛一看,不堪入目,可是经过大脑的再处理后句子的意思基本就明了了; 3.如果通过Google仍然无法理解,感觉就是不同,那肯定是对其中某个“常用单词”理解有误,因为某些单词看似很简单,但是在文献中有特殊的意思,这时就可以通过CNKI的“翻译助手”来查询相关单词的意思,由于CNKI的单词意思都是来源与大量的文献,所以它的吻合率很高。 另外,在翻译过程中最好以“段落”或者“长句”作为翻译的基本单位,这样才不会造成“只见树木,不见森林”的误导。 注: 1、Google翻译:https://www.360docs.net/doc/d315959039.html,/language_tools google,众所周知,谷歌里面的英文文献和资料还算是比较详实的。我利用它是这样的。一方面可以用它查询英文论文,当然这方面的帖子很多,大家可以搜索,在此不赘述。回到我自己说的翻译上来。下面给大家举个例子来说明如何用吧比如说“电磁感应透明效应”这个词汇你不知道他怎么翻译, 首先你可以在CNKI里查中文的,根据它们的关键词中英文对照来做,一般比较准确。 在此主要是说在google里怎么知道这个翻译意思。大家应该都有词典吧,按中国人的办法,把一个一个词分着查出来,敲到google里,你的这种翻译一般不太准,当然你需要验证是否准确了,这下看着吧,把你的那支离破碎的翻译在google里搜索,你能看到许多相关的文献或资料,大家都不是笨蛋,看看,也就能找到最精确的翻译了,纯西式的!我就是这么用的。 2、CNKI翻译:https://www.360docs.net/doc/d315959039.html, CNKI翻译助手,这个网站不需要介绍太多,可能有些人也知道的。主要说说它的有点,你进去看看就能发现:搜索的肯定是专业词汇,而且它翻译结果下面有文章与之对应(因为它是CNKI检索提供的,它的翻译是从文献里抽出来的),很实用的一个网站。估计别的写文章的人不是傻子吧,它们的东西我们可以直接拿来用,当然省事了。网址告诉大家,有兴趣的进去看看,你们就会发现其乐无穷!还是很值得用的。https://www.360docs.net/doc/d315959039.html, 3、网路版金山词霸(不到1M):https://www.360docs.net/doc/d315959039.html,/6946901637944806 翻译时的速度: 这里我谈的是电子版和打印版的翻译速度,按个人翻译速度看,打印版的快些,因为看电子版本一是费眼睛,二是如果我们用电脑,可能还经常时不时玩点游戏,或者整点别的,导致最终SPPEED变慢,再之电脑上一些词典(金山词霸等)在专业翻译方面也不是特别好,所以翻译效果不佳。在此本人建议大家购买清华大

文献翻译英文原文

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广东工业大学华立学院 本科毕业设计(论文) 外文参考文献译文及原文 系部经济学部 专业经济学 年级 2007级 班级名称 07经济学6班 学号 16020706001 学生姓名张瑜琴 指导教师陈锶 2011 年05月

目录 1挑战:小额贷款中的进入和商业银行的长期承诺 (1) 2什么商业银行带给小额贷款和什么把他们留在外 (2) 3 商业银行的四个模型进入小额贷款之内 (4) 3.1内在的单位 (4) 3.2财务子公司 (5) 3.3策略的同盟 (5) 3.4服务公司模型 (6) 4 合法的形式和操作的结构比较 (8) 5 服务的个案研究公司模型:厄瓜多尔和Haiti5 (9)

1 挑战:小额贷款中的进入和商业银行的长期承诺 商业银行已经是逐渐重要的运动员在拉丁美洲中的小额贷款服务的发展2到小额贷款市场是小额贷款的好消息客户因为银行能提供他们一完整类型的财务的服务,包括信用,储蓄和以费用为基础的服务。整体而言,它也对小额贷款重要,因为与他们广泛的身体、财务的和人类。如果商业银行变成重的运动员在小额贷款,他们能提供非常强烈的竞争到传统的小额贷款机构。资源,银行能廉宜地发射而且扩张小额贷款服务rela tively。如果商业广告银行在小额贷款中成为严重的运动员,他们能提出非常强烈的竞争给传统的小额贷款机构。然而,小额贷款社区里面有知觉哪一商业银行进入进入小额贷款将会是短命或浅的。举例来说,有知觉哪一商业银行首先可能不搬进小额贷款因为时候建立小额贷款操作到一个有利润的水平超过银行的标准投资时间地平线。或,在进入小额贷款,银行之后可能移动在-上面藉由增加贷款数量销售取利润最大值-或者更坏的事,退出如果他们是不满意与小额贷款的收益性的水平。这些知觉已经被特性加燃料商业银行的情形进入小额贷款和后来的出口之内。在最极端的,一些开业者已经甚至宣布,”降低尺度死!”而且抛弃了与主意合作的商业银行。 在最 signific 看得到的地方,蚂蚁利益商业银行可能带给小额贷款,国际的ACCION 发展发射而且扩张的和一些商业银行的关系小额贷款操作。在这些情形的大部分方面, ACCION 和它的合伙人正在使用方法,已知的当做服务公司模型,表演早答应当做一个能工作的方法克服真正的。 商业银行的障碍进入和穿越建立长命的小额贷款操作一个商业银行 这论文描述如何服务公司模型、住址商业银行中的主要议题进入进小额贷款,监定成功建立的因素动作井小额贷款服务公司,和礼物结果和小额贷款的课servic e 公司用最长的经验,在海地和审判官席 del 的 SOGEBANK│ SOGESOL 初期结果指出那这服务公司模型表现一重要的突破在促成商业银行进入和留在小额贷款。在厄瓜多尔的 Pichincha│ CREDIFE。初期结果指出服务公司模型在促成商业广告中表现一次重要的突破银行进入而且留在小额贷款。

仪表板外文文献翻译、中英文翻译、外文翻译

Dashboard From Wikipedia, the free encyclopedia This article is about a control panel placed in the front of the car. For other uses, see Dashboard (disambiguation). The dashboard of a Bentley Continental GTC car A dashboard (also called dash, instrument panel (IP), or fascia) is a control panel located directly ahead of a vehicle's driver, displaying instrumentation and controls for the vehicle's operation. Contents 1.Etymology 2.Dashboard features 3.Padding and safety 4.Fashion in instrumentation 5.See also 6.References Etymology Horse-drawn carriage dashboard Originally, the word dashboard applied to a barrier of wood or leather fixed at the front of a horse-drawn carriage or sleigh to protect the driver from mud or other debris "dashed up" (thrown up) by the horses' hooves.[1] Commonly these boards did not perform any additional function other than providing a convenient handhold for ascending into the driver's seat, or a small clip with which to secure the reins when not in use. When the first "horseless carriages" were constructed in the late 19th century, with engines mounted beneath the driver such as the Daimler Stahlradwagen, the simple dashboard was retained to protect occupants from debris thrown up by the cars' front wheels. However, as car design evolved to position the motor in front of the driver, the dashboard became a panel that protected vehicle occupants from the heat and oil of the engine. With gradually increasing mechanical complexity, this panel formed a convenient location for the placement of gauges and minor controls, and from this evolved the modern instrument panel,

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