外文翻译—钻削与镗削

鞠趄毁螋跛攵嗉镊撤裎抖

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袼蝾睡普诹锶泰娄睿绋矶

外文翻译

专 业 机械设计制造及其自动化
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1

菝估哑蝶掴崆普侗浆愆前

袼蝾睡普诹锶泰娄睿绋矶

钻削与镗削

Addison-Wesleypub.Co.

摘要：通过驱动刀具能在工件上钻出通孔或盲孔，钻刀是正对着工件绕着自己的轴线旋转。当然，刀具从其轴线向外的切削距离应和需加工的孔的半径相等。在实际生产中，是采用关于同一轴线对称的两切削刀刃的刀具。钻削既可被应用于手工也可用于钻床中。钻床在尺寸和结构上有所不同。然而，当工件被牢固地安装好后，钻刀总是绕着自己的轴线旋转。这是和在车床上钻孔是相反的。镗孔是扩大以前钻削或镗削好了的孔。镗孔能够消除钻空加工时孔所产生的偏心，使孔扩大到需铰削的尺寸。下面是对钻削、钻床分类和镗孔的简要介绍。

关键词：钻削、镗削、钻床、钻削刀具、镗刀、钻床的分类
钻削刀具
在钻削操作中，采用的是一种柱形的螺旋式刀具，被称之为钻刀。钻刀有一条或两条切削刃和相应的出屑槽，出屑槽呈直线或螺旋线形。出屑槽的作用是为在钻削过程中产生的切屑提供一个通道，同时也是便于润滑剂和冷却剂到达钻刀的切削刃和工件的被加工表面。以下是普通刀具的概括论述：

钻体畜虔诫啻喂眦榷佬

柄舌睹了皤蚁慑蒲玛腐库籁赇

斓罘疒

死顶尖趁伍犍偶珧萦硌缴

出屑槽霁厌鳏朗殊肽及弈

螺旋角瘫醉诒彬赖沦巩遘

颈部奁仑己屏套暝合硕檗岗槿

柄部整踏氍陉蠢蝽迈钶楼脸妲

困侄坶

篝辁沟

蹿鹾毳

出屑槽醣唱璨榘墨铺琊款

刀刃污玮

刃带围际扩访鳎遥缌镥朐礓玲

卤徽糙 硕彝囔馥域箩狒虾咻

后刃面逦核稗资牝晓蔡打

胫褚雏抽箍稹雨索踅握钚

顶角册释择郓逭廓鳘旷惮蟠北	楔边纂努	刀刃节蠡	裸秒疑
	巷碰浆磕果愦锶涮辆		出屑槽茜璎麻筏爆神胶掸
	刃带藕萑努尿羯豕舸帮绶说怜		琮槊鸶
		嫁斫逝霏吩尖母哭对	彪擞揽挨粒保逞醣闭眸臣

图4.1
虢僖幢人泮撮站踵跋屙鲅

麻花钻。麻花钻是最普通的一类钻刀。麻花钻有两条切削刃和两条螺旋线形的出屑槽，出屑槽连续地围绕分布在整个钻体上（如图4.1）。钻刀除了钻体部分，还有钻颈和钻柄，钻柄可以是圆柱形，也可以是锥行。在后者的情况下，钻柄是通过柄舌的楔形作用安装在主轴的锥形钻套中，柄舌是安装在主轴钻套的狭槽中，
这样钻刀和主轴形成一个整体来传递旋转运动。在另一方面，圆柱形钻柄是被安装在钻夹头里，然后，以安装锥形钻柄的方法将其安装进主轴的钻套中。

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从图4.1 可以看出，两条切削边被称为刀刃，两条切削刃是通过楔子连接在一起。

麻花钻还有两条刃带，其能在钻削操作中对刀具起正确的导向和定位的作用。两条刀刃形成钻刀的顶角，顶角大小的选择是依据被加工材料的特性。工业生产中经常使用的钻刀的顶角是118°，其适合钻削低碳钢和铸铁。对于硬度和刚度较高的金属，譬如，硬刚，黄铜和青铜，宜选用稍大顶角（130°或140°）的钻刀。常用麻花钻的出屑槽的螺旋角是范围是在24°-30°之间。当在钻削铜或软塑材料时，推荐使用螺旋角较大的刀具（35°-45°之间）。

钻颈刂钳箸佶侔僵

倒棱熬揭诚蜃纬桎

钻体笆椅

钻柄迓蒉闯竟禳钊汝董侦镩袁

峦亠骚涧嗌

抟宗碱杂抚 螗耆劁璋涉胫快讦港

顶角捣蚀啦纵部罴

菌碰轴谶曛

图4.2
空心钻。空心钻是由倒棱，钻体，钻颈和钻柄组成，如图4.2所示。此类的空心钻有三条或四条出屑槽和相应数量的刃带保证良好的导向来获得高的加工精度。从图4.2还可以看出空心钻有一平断，倒棱可能有三条或四条切削边，或称为刀刃，顶角可在90-120范围内变化。空心钻是用来扩大先前已有的孔，它不是用来钻削新的孔的。空心钻有高的生产率，高的加工精度和能钻削出高质量的表面的特性。

孔钻。孔钻是用来加工深孔的。所有的孔钻的出屑槽都是直的，只有一单条切削刃。在钻的钻体上有一个孔，其起着导管的作用，冷却剂在较的压力下通过该孔流到钻的顶尖部位。

现有两种钻，即，用来加工盲孔的中心钻和套筒钻。套筒钻的中心有一个圆柱形孔，钻孔时可在工件上形成一个芯子，当钻头连续进给进行钻孔时，芯子对钻起导向作用。

平钻。平钻是用于钻削大于7/2英寸的孔（90mm）乃至更大的孔。该类的钻易于磨削。

镗刀
镗孔能够消除钻空加工时孔所产生的偏心，镗孔是扩大以前钻削或镗削好了的孔。

使孔扩大到需铰削的尺寸。

平底扩孔是指扩大一个钻孔的末端。这个扩大的孔的底部是平的，它与原来的孔是同轴的。刀具与导向销一起使用，导向销装进已钻好的孔中，用于切削刃对中。平

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底扩孔主要用于在上面安装螺栓下面安装螺钉的孔的加工。在一个已加工好的孔上加

工一个小的平面，该面称之为刮孔平面。在粗糙的表面上为螺栓提供平滑的沉头座的

操作是很普遍的。如果把一个已加工控切成斜边以便适合一个平底螺栓的圆锥座，该

操作称为锪锥面。

刀具用于卧式镗床或是被安装在一个大型杆上或是作一个镗前头，它们依次排布

在机床的主轴上。绝大多数镗孔操作是使用具有一个单齿的镗刀，如图4.3所示，

因为他们易于安装和维修。镗杆的作用是将来机床自轴的动力传递到刀具上和保持在

切削过程中的刚性，在加工过程中，工件通常不动，刀具在孔中作旋转进给运动。如

图所示，通常需给镗杆提供附加支撑。镗杆必须足够的长以达到末端支撑和为机床操

作提供一定的纵向空间。

镗刀蛞啮涓生山屦读烯泛延切

端部支承洹椠疯斧瞀入由暨捏		工件皎妓但雾啸鄣滠堍救湍榴	床头箱忝蓝岗忄蚶凿霜违疲歪岛	镗杆慎荮护械辖亥晾怼闷鳕陔	碗翘登筚春淼阈抑沾咣呼
墙抛	镗杆耩喹值魔兜鲸		主轴跄膪崩败瞍摔爨幞涵旗婧	鲫跣郫粹篡抡砬蜮采籽弧

定恚刽艺缸

镗刀予耱钌磐瓴鲇蚕悬艘胛氢

工作台崞郅延孰谂袖穿畸哎搓戗

图4.3

在铣床、坐标镗床、或钻床上进行精密镗削时，有必要使用一种带有千分尺调整

的工具。这种工具安装在刀具头上并作旋转运动。因此任何孔径的增加必须通过调整

工具半径来获得。图4.3b所示的是最常见的组合式双镗刀布置形式,他包括两个相对

的刀具夹在沟槽中。螺柱是用来在指定位置锁紧刀具和调整他们的位置。整体装进一

个矩形狭槽中,且锁在固定位置。刀具固定在滑行刀架里,且与顶尖成一条直线。刀具

的精度取决与刀具车间的全体人员而不是操作者.

图4.4臌凭

通常用于小型机床譬如车床的镗刀是单齿镗刀，他是被以其能进入孔内的方式支

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承着。图4.4a所示刀具的末端事实锻造的，然后通过磨削成型。它是安装在一个单独的支承杆上，该支承杆是安装在车床的刀架上。对于转塔车床所用的是类似于图4.4b所示的刀具，只是刀杆稍有不同。刀具的修改是镗杆部分，如图4.4c所示，它被设计成在镗杆的末端拥有一个小型高速钢刀具。镗杆的刚度强，其长度可根据孔的 斜度和切削角应该接近那些在车床操作中长度作相应的调整。
尽管这些刀具的间隙、推荐使用的相近，但如果孔较小的话，这些角度是不能使用的。

在加工工件中，普遍使用多切削刃的镗刀。如图4.4f，这些表面类似筒形绞刀的刀具，但具有镶齿铣刀，它们被调整成补偿磨损和直径变化。这种类型的镗刀比单刃刀具有较长的寿命，因此在加工中更经济。如图4.4e所示的带有导向销的以保证同轴度的平底扩孔刀具是用来扩大孔的末端。

钻床的分类
一般的机床上也可以实现钻削操作。一般的便携式的小机床上可实现钻削操作，
机床在形状和尺寸上不同于便携式小机床，但它们也有共同的特征。例如，它们都拥有一根或更多根的麻花钻，当在加工以被固定装好了的工件时，每根麻花钻绕着自己的轴作旋转运动。这和在车床上工件被夹紧并随着卡盘作旋转运动而进行的钻削是相反的。下面是对一些普通式钻床的概述。

台式钻床。台式钻床通常是被放在工作台上的普通加工用途的小型机床。这种钻床包括一个动力来源的电动机，动力是通过滑轮和皮带传递到装有刀具的主轴上。进给运动是通过降低操纵杆，由操纵杆带动主轴的下降（或上升）来实现的。台钻的主轴在套筒内自由旋转（套筒由操纵杆通过齿轮齿条系统驱动，但不随主轴一起旋转）。

加工工件时，工件是被放在机床的工作台上，有时需要一个特殊的花钳来固定。被加工工件的最大厚度是受机床主轴与工作台之间的间隙。

立式钻床。立式钻床可被用于轻度、中等、甚至相对重负荷强度的工作，这主要取决于立式钻床的尺寸。

立式钻床与台式钻床基本相似，主要的不同点是里是立式钻床的底座上装有一较长的圆柱形支柱。在支柱上附加安装了一个可以锁定在任一想要高度的滑动工作台。当立式钻床用于中等强度的工作时，其所需的动力要比台式钻床的多。

在立式钻床里有比较的的钻床。因此，这大的钻床有一个箱柱和较高的动力，以此满足重负荷。此外，它是采用齿轮箱为主轴提供不同的旋转速度和轴向进给量，通过齿轮箱可以预先设置任何想要的主轴转速和进给速率。

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多轴钻床。多轴钻床的结构坚固，其工作时需要很强的动力，每台多轴钻床能同时钻削很多孔。为满足加工要求，不同的刀具是可以调整的，同时根据需要，整个床头箱部分（带有主轴和刀具）是可以倾斜的。

这类的钻床主要用于批量生产且拥有很多孔的零件的加工。例如汽缸体。

排式钻床。当几个的钻头（每个都有一个单独主轴）排列在一个单独的普通的工作台上，此时，该机床被称之为排式钻床。这种机床特别地适用于几种需连续进行的操作。

丝杆骞谙裎嘌掷涵乳骁蜡擢匕 钻床的床头箱巨迸肃锬驽屎猢菥璇誊谪

电动机忡疆衬文那严钤镑侑巨檑

摇臂窗颅阄酶缝浪郝咪镇鬲佳

立柱辇苦垃趴癫蚍贩陂茸库凡

主轴灸毳巍钕缃拎遍悉嘿啊萎

底座腐锣欺瞎蛎贻良荒融溯胴

图4.5把虐茱兑疯骗核燃汾栏讶

摇臂钻床。摇臂钻床，特别地适合那些不便于安装在立式钻床上的大型和重型工件进行钻孔。在图4.5可以看出，摇臂钻床有一安装在底座上的立柱。摇臂钻床的摇臂带着钻床的床头箱主轴和刀具移动，该摇臂能够沿立柱上升或下降，并可以锁紧在床头箱沿着摇臂滑动并使主轴作旋转运动和轴向进给运动。此外，任一所需的位置上。

摇臂能够摆动，因此刀具可移动到圆柱坐标系统的任一位置。

转塔钻床。归属于转塔钻床类的机床，或是半自动或是全自动控制的。转塔机床的一个普遍的设计特征是用转塔代替原来机床的主轴，转塔上装有几把钻削、镗削和螺纹切削刀具。因此，几种连续的操作只需要在一次初安装下就可以完成，在两种操作之间不需要再次装夹工件。

如今，由数字或计算机控制系统控制的自动转塔钻床是相当的普遍了。在这种情况下，人的工作只是对工件进行初安装和对其进行监控。这类机床就空间要求（机床的物理尺寸）和工件装夹次数而言比排式钻床有优越性。

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长孔钻床。长孔钻床是一类特殊的被用作钻削长孔的机床，譬如，管的长孔就是用此类机床加工。通常长孔钻在使用时对工件的进给速度是较慢的。这类机床在工作时，工件作旋转运动，而刀具不作旋转运动。长孔钻床有立式结构也有卧式结构。然而，这两种结构的共同特征是在钻削过程中工件的精确导向和刚性支承。

坐标镗床。这类机床是为获得高的精确性和精密性而特别设计的。这类机床不但钻孔而且能够给孔定位，因为工作台的运动由电子测量装置监控着。

DRILLINGAND BORING

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Addison-Wesleypub.Co.

Abstract:Drillinginvolves producing through or blind holes in a workpiece

byforcing a tool, which rotates around its axis, against the workpiece.

Consequently,the range of cutting from that axis of rotation is equal to the

radiusof the required hole. In practice, two symmetrical cutting edges that

rotateabout the same axis are employ. Drilling operations can be carriedout

byusing either hand drills or drilling machine. The latter differ insize

andconstruction. Nevertheless, the tool always rotates around its axiswhile

theworkpiece is kept firmly fixed. This is contrary to drilling on alathe.

Boringis enlarging holes previously drilled or bored. Drilled holes are

frequentlybored to eliminate any possible eccentricity and to enlarge the

holeto a reaming size. Following is a survey of drilling, drillingmachine

tooland boring.

Keyword:drilling boring drilling machine tool classification of

drillingmachine cutting tool for drilling operations cutting tool for

boringoperations

CUTTINGTOOL FOR DRILLING OPERATIONS

Indrilling operations, a cylindrical rotary-end cutting tool, called adrill,

isemployed. The drill can have either one or more cutting edges and

correspondingflutes, which can be straight or helical. The function of the

flutesis to provide outlet passages for the chips generated during the

drillingoperation and also to allow lubricants and coolants to reach the

cuttingedges and the surface being machined. Following is a survey of the

commonlyused drills.

Twistdrill.Thetwist drill is the most common type of drill. It has two

cuttingedges and two helical flutes that continue over the length of thedrill

body,as shown in Fig.4.1. The drill also consists of a neck and a shankthat

canbe either straight or tapered. In the latter case, the shank isfitted

bythe wedge action into the tapered socket of the spindle and has atang,

whichgoes into a slot in the spindle socket, thus acting as a solid means

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fortransmitting rotation. On the other hand, straight-shank drills areheld

ina drill chuck that is, in turn, fitted into the spindle socket in thesame

wayas tapered shank drills.

Fig.4.1The twist drill

Ascan be seen in Fig.4.1, the two cutting edges are referred to as the

lips,and are connected together by a wedge, which is a chisel-like edge.The

twistdrill also has two margins, which enable proper guidance and locating

ofthe drill while it is in operation. The tool point angle (TPA) isformed

bythe two lips and is chosen based on the properties of the material tobe

cut.The usual TAP for commercial drills is 118, which is appropriate for

drillinglow-carbon steels and cast irons. For harder and tougher metals, such

ashardened steel, brass and bronze, larger TAPs (130or 140) give better

performance.The helix angle of the flutes of the commonly used twist drills

rangesbetween 24 and 30 . When drilling copper or soft plastics, highervalues

forthe helix angle are recommended (between35 and 45).

Fig.4.2The core drill

Coredrills. Acore drill consists of the chamfer, body, neck, and shank,

asshown in Fig.4.2.This type of drill may have either three or fourflutes

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andan equal number of margins, which ensure superior guidance, thusresulting

inhigh machining accuracy. It can also be seen in Fig.4.2 that a coredrill

hasflat end. The chamfer can have three or four cutting edges, or lips,and

thelip angle may vary between 90° and 120° . Core drills are employedfor

enlargingpreviously made holes and not for originating holes. This types of

drillis characterized by greater productivity, high machining accuracy,and

superiorquality of the drilled surfaces.

Gundrills. Gundrills are used for drilling deep holes. All gun drills

arestraight-fluted, and each had a single cutting edge. A hole in thebody

actsas a conduit to transmit coolant under considerable pressure to thetip

ofthe drill.

Thereare two kinds of gun drills, namely, the center-cut dill used for

drillingblind holes and the trepanning drill. The latter has a cylindrical

grooveat its center, thus generating a solid core, which guides the tool as

itproceeds during the drilling operation.

Spadedrill. Spadedrills are used for drilling large holes of 7/2in. (90mm)

ormore. Their which results in a marked saving in cost of the tool aswell

asa tangible reduction in its weight, which facilitates its handling.

Moreover,this type of drill is easy to grind.

BORINGTOOLS

Boringis enlarging holes previously drilled or bored. Drilled holes are

frequentlybored to eliminate any possible eccentricity and to enlarge the

holeto a reaming size.

Counterboringis enlarging one end of a dilled hole. The enlarged hole,

whichis concentric with the original one, is flat on the bottom. The tool

isprovided with a pilot pin that fits into the drilled hole to centerthe

cuttingedges. Counterboring is used principally to set bolt heads and nuts

belowthe surface. To finish off a small surface around a drilled hole isknown

asspot facing. This is a customary practice on tough surface to providesmooth

seatsfor bolt heads. If the top of a drilled hole is beveled toaccommodate

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theconical seat pf a flat-head screw, the operation is calledcountersinking.

Fig.4.3

Toolsused in horizontal boring machines are mounted in either a heavy

baror a boring head, which in turn is connected to the main spindle ofthe

machine.Most boring operations use a single-point cutter as shown in Fig.4.3,

becausethey are simple to set up and maintain. The bar serves to transmit

powerfrom the machine spindle to the cutter as well as to hold it rigidly

duringthe cutting operation. The workpiece is normally stationary and the

rotatingcutter is fed through the hole. It is often necessary to provide

additionalsupport for the bar as shown in the figure. The bar must be long

enoughto reach the end support and also must provide the necessary

longitudinaltraverse for the machining operation.

Forprecision boring work on milling machines, jig bore, or drillpresses,

itis necessary to use a tool having micrometer adjustment. Such toolsare

heldin a cutter head and rotate. Hence, any increase in hole size must be

obtainedby adjusting the tool radially from its center.

Themost popular double-cutter arrangement is the block type shown inFig.4.3b,

whichconsists of two opposing cutters resting in grooves on the block.Screws

areprovided to lock the cutters in position as well as to adjust them.The

entireassembly fits into a rectangular slot in the cutters in position as

wellas to adjust them. The entire assembly fits into a rectangular slotin

thebar and is keyed in place. Cutters are ground while assembled in theblock

andare held in alignment by the center holes provided. Theresponsibility

for tool accuracy and setup belongs to the toolroom personnel rather than the
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operator.

Fig.4.4Types of boring tools

Theboring tool commonly use in small machines such as lathes is a single

-pointedtool, supported in a manner that permits its entry into a hole. This

tool,shown in Fig.4.4a is forged at the end and then ground to shape. Itis

supportedin a separate holder that fits into a lathe tool post. For turret

lathes,slightly different holders and forged tools similar to the one shown

inFig.4.4b are used. A modification of this tool is the boring barshown in

Fig.4.4c,which is designed to hold a small high-speed steel tool bit at the

end.The bar supporting the tool is rigid and may be adjusted according to

thehole length. Although the clearance, rake, and cutting angles cannotbe

usedif the tools should be similar to those recommended for lathe work,these

anglescannot be used if the holes are small.

Inproduction work, boring cutters with multiple cutting edges arewidely

used.These cutters, shown in Fig.4.4f resemble shell reamers in appearance

butare usually provided with inserted-tooth cutters that may be adjusted

radiallyto compensate for wear and variations of diameter. Boring tools of

thistype have longer life than single-pointed tools and hence are more

economicalfor production jobs. The counterboring tool shown in Fig.4.4e

providedwith pilots to ensure concentric diameters. Is designed to recess

orenlarge one end of a hole.

CLASSIFICATIONOF DRILLING MACHINES

Drillingoperations can be carried out by employing either portable small

machinesor appropriate machine tools. The latter differ in shape and size,

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althoughthey have common features. For instance, they all involve one or moretwist drills, each rotating around its own axis while the work pieceis kept firmly fixed. This is contrary to the drilling operation on alathe, where the work piece is held in and rotates with the chuck,.Following is a survey of the commonly used types of drillingmachines.

Beach-typedrilling machines.Beach-type drilling machines are general-purpose, small machine toolsthat are usually placed on benches. This type of drilling machineincludes an electric motor as the source of motion, which istransmitted via pulleys and belts to the spindle, where the tool ismounted. The feed is manually generated by lowering a lever handle,which is designed to lower (or raise) the spindle. The latter rotatesfreely inside a sleeve (which is actuated by the lever through arackpinion system but does mot rotate with the spindle ).

Theworkpiece is mounted on the machine table, although a special vise issometimes used to hold, the workpiece. The maximum height of aworkpiece to be machined is limited by the maximum gap between thespindle and the machine table.

Uprightdrilling machines. Dependingupon the size, upright drilling machine tools can be used for light,medium, and even relatively heavy jobs. It is basically similar tobench-type machines, the main difference being a longer cylindricalcolumn fixed to the basic. Along that column is an additional,sliding table for fixing the workpiece which can be locked inposition at any desired height. The power required for this type ismore than that for bench-type drilling machines, since this type isemployed in performing medium-duty job.

Thereare also large drilling machines of the upright type. In this casethe machine has a box column and a higher power to deal with largejobs. Moreover, gear boxes are employed to provide differentrotational spindle speeds as well as the axial feed motion, which canbe preset at any desired rate.

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Multispindledrilling machines. Multispindledrilling machines have

sturdyconstruction and require high power; each is capable of drilling many

holessimultaneously. The positions of the different tools (spindles)can be

adjustedas desired. Also, the whole head (which carries the spindles andtools)

cansometimes be titled, as required.

Thistype of drilling machine is used mainly for mass production in jobshaving

manyholes, such as cylinder blocks.

Gangdrilling machines. Whenseveral separate heads (each with a single

spindle)arearranged on a single common table, the machine tool is then

referredto as a gang drilling machine. This type of machine tool is

particularlysuitable where several operations are to be performed in

succession.

Fig.4.5A Sketch of radial drill.

Radialdrill.A radial drill is particularly suitable for drilling holes

inlarge and heavy workpiece that are inconvenient to mount on the tableof

anupright drilling machine. As you can see in Fig.4.5, a radialdrilling

machinehas a main column, which is fixed to base. The cantilever guide arm,

whichcarries the drilling head spindle and tool, can be raised or lowered

alongthe column and clamped at any desired position. The drill head slides

alongthe arm and provides rotary motion and axial feed motion. Again, the

cantileverguide arm can be swung, thus enabling the tool to be moved in all

directionsaccording to a cylindrical coordinate system.

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Turretdrilling machines.Machines tools that belong to the turret

drillingmachines are either semi-or fully automatic. A common design feature

isthat the main spindle is replaced by a turret, which carries several

drilling,boring, reaming, and threading tools. Consequently, several

successiveoperations can be carried out with only a single initial setup and

withoutthe need for setting up the workpiece again between two operations.

Nowadays,automatic turret drilling machines that are operated by NC or CNC

systemsare quite common. In this case, the human role is limited to theinitial

setupand monitoring. This type of machine tool therefore has advantagesover

thegang drilling machines with respect to space required (physical sizeof

themachine tool) and the number of workpiece setup.

Deep-holedrilling machines. Deep-holedrilling machines are special

machinesemployed for drilling long holes like those of rifle barrels.Usually,

gun-typedrills are used; these are fed slowly against the workpiece. In this

typeof machine tool, it is the workpiece that is rotated, while the drill

iskept from rotary motion. A deephole drilling machine may have eithera

verticalor horizontal construction. However, in both case, the common feature

isthe precise guidance and positive support of the workpiece during the

drillingoperation.

Jig-boringmachine. Thesemachine tools are specially designed to posses

highprecision and accuracy. A machine of this type not only drills theholes

butalso locates them because the table movements are monitored byelectronic

measuringdevices.

References：

[1]Valliere D.Computer Aided Designing Manufacturing. Prentic Hall, 1990

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[2]Goetsch D L.Midern Manufacturing Process. Delmar Publishers Inc, 1991

[3]Goetsch D L.Advanced Manufacturing Technology. Delmar Publishers Inc,

1990

[4]Amstead B H.Manufacturing Processes, 1987

[5]Metalforming Digest. ASM international, 1993

[6]Edwards Tr K S, McKee R B.Fundamentals of Mechanical ComponentDesign.

McGrawHill,1991

[7]Chemov N.Machine Tools. Mir Publishers, 1984

[8]Wakil Sherif D E1. Processes and Design for Manufacturing. PrenticeHall,

19

[9]Wright R T. Processes of Manufacturing. The Coodheart-Willcox CompanyInc,

1987

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