专业英语2124.docx

专业英语2124.docx

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专业英语2124

21.Thelathe

Vocabulary:

lathe[]车床

ordinary[]普通的

carryout完成,实现,执行

versatile[]通用的

workshop[]车间

capable[]有能力的

component[]成分

headstock[]主轴箱

tailstock[]尾架

tool-post刀架，刀座

cross-slide横向拖板

job[]工件

matter[]有关系,要紧

sidewards[]横着,向旁边地

saddle[]溜板箱

carriage[]溜板箱

accommodate[]提供

turret[]转动架，转塔

revolve[]旋转

twist[]扭曲

incorporate[]合并

center[]顶尖

spindle[]主轴

largely[]主要地

matter[]有关系,要紧

taper[]锥形

nose[]前端

firmly[]稳固的

uniform[]统一的

rough[]粗糙的

chuck[]卡盘

lead-scerw丝杠

feed-shaft进给杆

finishingcut精加工

finish[]光洁度、粗糙度

front-plate花盘

jaw[]夹爪

drill[]钻孔

bore[]镗孔

thread[]螺纹

transverse[]横向的

engage[]连结，接合，啮合

pitch[]螺距

alter[]改变

reverse[]反向的

reversinglever反向手柄

original[]最初的

Text:

Thelatheisoneofthemostusefulandversatilemachineintheworkshop,andiscapableofcarryingoutawidevarietyofmachiningoperations.Themaincomponentsofthelathearetheheadstockandtailstockatoppositeendsofabed,andatool-postbetweenthemwhichholdsthecuttingtool.Thetool-poststandsonacross-slidewhichenablesittomovesidewardsacrossthesaddleorcarriageaswellasalongitdependingonthekindofjobitisdoing.Theordinarycenterlathecanaccommodateonlyonetoolatatimeonthetool-post,butaturretlatheiscapableofholdingfiveormoretoolsontherevolvingturret.Thelathebedmustbeverysolidtopreventthemachinefrombendingortwistingunderstress.

Theheadstockincorporatesthedrivingandgearmechanism,andaspindlewhichholdstheworkpieceandcausesittorotateataspeedwhichdependslargelyonthediameteroftheworkpiece.Abaroflargediametershouldnaturallyrotatemoreslowlythanaverythinbar;thecuttingspeedofthetooliswhatmatters.Taperedcenterinthehollownoseofthespindleandofthetail-stockholdtheworkfirmlybetweenthem.Afeed-shaftfromtheheadstockdrivesthetool-postalongthesaddle,eitherforwardsorbackwards,atafixedanduniformspeed.Thisenablestheoperatortomakeaccuratecutsandtogivetheworkagoodfinish.Gearsbetweenthespindleandthefeed-shaftcontrolthespeedofrotationoftheshaft,andthereforetheforwardorbackwardmovementofthetool-post.Thegearwhichtheoperatorwillselectdependsonthetypeofmetalwhichheiscuttingandtheamountofmetalhehastocutoff.Foradeeporroughingcuttheforwardmovementofthetoolshouldbelessthanforafinishingcut.

Centersarenotsuitableforeveryjobonthelathe.Theoperatorcanreplacethembyvarioustypesofchucks,whichholdtheworkbetweenjaws,orbyafront-plate,dependingontheshapeoftheworkandtheparticularcuttingoperation.Hewilluseachuck,forexample,toholdashortpieceofwork,orworkfordrilling,boringorscrew-cutting.Atransversemovementofthetool-postacrossthesaddleenablesthetooltocutacrossthefaceoftheworkpieceandgiveitaflatsurface.Forscrewcutting,theoperatorengagesthelead-screw,alongscrewedshaftwhichrunsalonginfrontofthebedandwhichrotateswiththespindle.Thelead-screwdrivesthetool-postforwardsalongthecarriageatthecorrectspeed,andthisensuresthatthethreadsonthescrewareofexactlytherightpitch.Theoperatorcanselectdifferentgearspeeds,andthiswillaltertheratioofspindleandlead-screwspeedsandthereforealterthepitchofthreads.Areversingleverontheheadstockenableshimtoreversethemovementofthecarriageandsobringthetoolbacktoitsoriginalposition.

Appending:

Lathe,MillingMachine,Planer,andShaper

Aselectionofbasicmachinetoolsshowsavarietyoffunctionsandmethodsofcraftingaworkpiece.Thejobathandusuallydetermineswhichtoolwillbeused.Forinstance,apersonmakingaroundedhandlewouldusealathe,whileapersonmakingabreadboardwoulduseaplaner.Inordertousepowertoolsefficientlyandsafely,eithertheworkpieceortheactualtoolmustbestationary.Aplanerisanexampleofastationarymachinetoolbecausetheworkpieceismoved,orfed,intoit.Tousetheshaper,theworkpiecemustbekeptstationarywhilethetoolismovedacrossit.

Conventionalmachinetoolsprepareworkpiecesforfurtherfittinganduse.Drills,grinders,punchpresses,surfacegrinders,andboringmachinesareusedextensivelyinindustry.Particularlyusefulinlarge-scaleproduction,thesepowertoolsproduceuniformholesandsmoothsurfacesfarfasterandmoreaccuratelythantheycouldbeproducedbyhand.

22.Milling,Shaper,PlanerandGrindingMachines

Vocabulary:

mill[]铣削

arbor[]刀杆

spacer[]垫块

bushing[]套筒

yoke[]支座，支架

kneel[]升降台

column[]立柱

elevatingscrew升降丝杠

indexhead分度头

table[]工作台

footstock底座

arboryoke刀杆支座

lever[]杆

right[]垂直的，直角的

swivel[]旋转

transverseslide横滑板

peel[]削，剥

chip[]屑片

shaper[]牛头刨床

planer[]龙门刨床

reciprocating[]往复的

perpendicular[]垂直的

normal[]法向的，垂直的

apron[]挡板

ram[]滑枕

stroke[]行程

vise[]台钳，虎钳

fixture[]夹具

rocker[]摇杆

regulate[]调节

clamp[]夹紧

pawl[]棘爪

notch[]槽口

ratchet[]棘齿

crossrail[]横梁

fasten[]拴紧,使固定

toolhead刀架

grind[]磨削

cylindrical[]圆柱的

conical[]圆锥形的

accurately[]精确地

surplus[]剩余的

external[]外部的

internal[]内部的

principal[]主要的

longitudinally[]纵向地，经度地

respectively[]各自地

concentricity[]同心

periphery[]外围

groundwork基准

axis[]轴心线

finish[]粗糙度

millingmachine铣床

millingcutter铣刀

universalmillingmachine万能铣床

cuttergrinder工具磨床

surfacegrinder平面磨床

centerlessgrinder无心磨床

externalgrinder外圆磨床

internalgrinder内圆磨床

Text:

Millingmachines

Themillingmachineisamachinethatremovesmetalfromworkwitharevolvingmillingcutterastheworkinfedagainstit.

Themillingcutterismountedonanarborwhereitisheldinplacebyspacersorbushing.Thearborisfixedinthespindlewithoneend,whiletheotherendofthearborrotatesinthebearingmountedonthearboryoke.

Themostimportantpartsofthemillingmachineare:

1）startinglevers;2）spindle;3）column;4）knee;5）elevatingscrew;6）table;7）indexhead;8）speedlevers;9）feedlevers;10）tablemovementlevers;11）footstock;12）arboryoke.

Thespindleofthemillingmachineisdrivenbyanelectricmotorthroughatrainofgearsmountedinthecolumn.

ThetableoftheplainmillingmachinemaytravelonlyatrightanglestothespindlewhiletheUniversalMillingMachineisprovidedwithatablethatmaybeswiveledonthetransverseslideformillinggearteeth,threads,etc.

ShaperandPlaner

Themachinetoolsofthisgrouparegenerallyusedformachiningflatsurfaces,whichisusuallyperformedbyacutterthatpeelsthechipfromthework.Themainmotionisreciprocatingandthefeedisnormal（perpendicular）tothedirectionofthemainmotion.

Thetoolandtheapronofashaperarelocatedontheram.Achipispeeledofftheworkontheforwardstroke.Anadjustabletablewith"T"-slotsholdswork,vise,andotherfixturesforholdingthework.

Theshaperhasarockerarmwhichdrivestheram,andamechanismforregulatingthelengthofthestroke.Theramsupportsthetoolhead.Theheadcarriesthedownfeedmechanismandwillswivelfromsidetosidetopermitthecuttingofangles.Thisisgenerallyahandfeed,butsomeshapersarerequiredwithapowerdownfeedinadditiontotheregularhanddownfeed.

Thetableoftheshaperisofboxformwith"T"-slotsonthetopandsidesforclampingthework.Thecrossrailisbolteddirectlytotheframeorcolumnoftheshaperwithbolts.

Theautomaticfeedorpowerfeedisobtainedbyapawlwhichengagesinanotchedwheelorratchet.

Themainpartsoftheplanerincludethebed,thetablethatmovesbackandforth,thecolumn,thecrossrailwhichmovesupanddownonthecolumn,andthetoolheadsthatarefastenedtothecrossrail.

Grindingmachines

Agrindingmachineisamachinewhichemploysagrindingwheelforproducingcylindrical,conicalorplanesurfacesaccuratelyandeconomicallyandtothepropershape,size,andfinish.Thesurplusstockisremovedbyfeedingtheworkagainsttherevolvingwheelorbyforcingtherevolvingwheelagainstthework.

Thereisagreatvarietyofgrindingmachines.Themachinesthataregenerallyusedarecuttergrinder,surfacegrinder,centerlessgrinder,externalgrinder,internalgrinder.

PrincipalpartsofaPlainGrindingMachine:

1.Base.

Themaincastingofaplaingrindingmachineisabasethatrestsonthefloor.

2.Tables.

Aslidingtable,whichismountedonwaysatthefrontandtopofthebase,maybemovedlongitudinallybyhandorpowertofeedworkpiecespastthefaceofthegrindingwheel.

3.HeadstockandTailstock.

Amotor-drivenheadstockandatailstockaremountedontheleftandrightends,respectively,oftheswiveltableforholdingworkpiecesoncenters.Theheadstockcenteronagrinderisadeadcenter,thatisbothcentersare"dead"toinsureconcentricityoftheperipheryofgroundworkwithitsaxis.

4.Wheelhead.

Awheelheadthatcarriesagrindingwheelanditsdrivingmotorismountedonaslideatthetopandrearofthebase.Thewheelheadmaybemovedper