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c6132 改装 双工 数控 缸体 钻床 设计

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（1）组合机床由70～90%的通用零、部件组成，可以缩短设计和制造周期。而且在需要的时候，还可以部分或全部进行改装，以组成适应新加工要求的新设备。这就是说，组合机床有重新改装的优越性，其通用零、部件可以多次重复利用。组合机床是按具体加工对象专门设计的，可以按最佳工艺方案进行加工。

（2）在组合机床上可以同时从几个方向采用多把刀具对几个工件进行加工，是实现集中工序，提高生产效率的最好途径。

（3）机床是在工件一次装夹下用多轴实现多孔同时加工，有利于保证各孔相互之间的精度要求，提高产品质量；减少了工件工序间的搬运，改善了劳动条件；减少了占地面积。

（4）由于组合机床大多零、部件是同类的通用部件，简化了机床的维护和修理。

（5）组合机床的通用部件可以组织专门工厂集中生产，有利于提高产品质量和技术水平，降低制造成本。

内容简介：

EXPERIMENTALINVESTIGATIONOFLASERSURFACETEXTUREDPARALLELTHRUSTBEARINGSIETSION,GHALPERIN,VBRIZMERANDYKLIGERMANDEPTOFMECHANICALENGINEERINGTECHNION,HAIFA32000,ISRAELRECEIVED14SEPTEMBER2003ACCEPTED29DECEMBER2003PERFORMANCEENHANCEMENTSBYLASERSURFACETEXTURINGLSTOFPARALLELTHRUSTBEARINGSISEXPERIMENTALLYINVESTIGATEDTESTRESULTSARECOMPAREDWITHATHEORETICALMODELANDGOODCORRELATIONISFOUNDOVERTHERELEVANTOPERATINGCONDITIONSACOMPARISONOFTHEPERFORMANCEOFUNIDIRECTIONALANDBIDIRECTIONALPARTIALLSTBEARINGSWITHTHATOFABASELINE,UNTEXTUREDBEARINGISPRESENTEDSHOWINGTHEBENEFITSOFLSTINTERMSOFINCREASEDCLEARANCEANDREDUCEDFRICTIONKEYWORDSFLUIDFILMBEARINGS,SLIDERBEARINGS,SURFACETEXTURING1INTRODUCTIONTHECLASSICALTHEORYOFHYDRODYNAMICLUBRICATIONYIELDSLINEARCOUETTEVELOCITYDISTRIBUTIONWITHZEROPRESSUREGRADIENTSBETWEENSMOOTHPARALLELSURFACESUNDERSTEADYSTATESLIDINGTHISRESULTSINANUNSTABLEHYDRODYNAMICFILMTHATWOULDCOLLAPSEUNDERANYEXTERNALFORCEACTINGNORMALTOTHESURFACESHOWEVER,EXPERIENCESHOWSTHATSTABLELUBRICATINGFILMSCANDEVELOPBETWEENPARALLELSLIDINGSURFACES,GENERALLYBECAUSEOFSOMEMECHANISMTHATRELAXESONEORMOREOFTHEASSUMPTIONSOFTHECLASSICALTHEORYASTABLEFLUIDFILMWITHSUCIENTLOADCARRYINGCAPACITYINPARALLELSLIDINGSURFACESCANBEOBTAINED,FOREXAMPLE,WITHMACROORMICROSURFACESTRUCTUREOFDIERENTTYPESTHESEINCLUDEWAVINESS1ANDPROTRUDINGMICROASPERITIES24AGOODLITERATUREREVIEWONTHESUBJECTCANBEFOUNDINREF5MORERECENTLY,LASERSURFACETEXTURINGLST68,ASWELLASINLETROUGHENINGBYLONGITUDINALORTRANSVERSEGROOVES9WERESUGGESTEDTOPROVIDELOADCAPACITYINPARALLELSLIDINGTHEINLETROUGHNESSCONCEPTOFTONDER9ISBASEDONEECTIVECLEARANCEREDUCTIONINTHESLIDINGDIRECTIONANDINTHISRESPECTITISIDENTICALTOTHEPARTIALLSTCONCEPTDESCRIBEDINREF10FORGENERATINGHYDROSTATICEECTINHIGHPRESSUREMECHANICALSEALSVERYRECENTLYWANGETAL11DEMONSTRATEDEXPERIMENTALLYADOUBLINGOFTHELOADCARRYINGCAPACITYFORTHESURFACETEXTUREDESIGNBYREACTIVEIONETCHINGOFSICPARALLELTHRUSTBEARINGSSLIDINGINWATERTHESESIMPLEPARALLELTHRUSTBEARINGSAREUSUALLYFOUNDINSEALLESSPUMPSWHERETHEPUMPEDFLUIDISUSEDASTHELUBRICANTFORTHEBEARINGSDUETOTHEPARALLELSLIDINGTHEIRPERFORMANCEISPOORERTHANMORESOPHISTICATEDTAPEREDORSTEPPEDBEARINGSBRIZMERETAL12DEMONSTRATEDTHEPOTENTIALOFLASERSURFACETEXTURINGINTHEFORMOFREGULARMICRODIMPLESFORPROVIDINGLOADCARRYINGCAPACITYWITHPARALLELTHRUSTBEARINGSAMODELOFATEXTUREDPARALLELSLIDERWASDEVELOPEDANDTHEEECTOFSURFACETEXTURINGONLOADCARRYINGCAPACITYWASANALYZEDTHEOPTIMUMPARAMETERSOFTHEDIMPLESWEREFOUNDINORDERTOOBTAINMAXIMUMLOADCARRYINGCAPACITYAMICRODIMPLECOLLECTIVEEECTWASIDENTIFIEDTHATISCAPABLEOFGENERATINGSUBSTANTIALLOADCARRYINGCAPACITY,APPROACHINGTHATOFOPTIMUMCONVENTIONALTHRUSTBEARINGSTHEPURPOSEOFTHEPRESENTPAPERISTOINVESTIGATEEXPERIMENTALLYTHEVALIDITYOFTHEMODELDESCRIBEDINREF12BYTESTINGPRACTICALTHRUSTBEARINGSANDCOMPARINGTHEPERFORMANCEOFLSTBEARINGSWITHTHATOFTHETHEORETICALPREDICTIONSANDWITHTHEPERFORMANCEOFSTANDARDNONTEXTUREDBEARINGS2BACKGROUNDACROSSSECTIONOFTHEBASICMODELTHATWASANALYZEDINREF12ISSHOWNINFIGURE1ASLIDERHAVINGAWIDTHBISPARTIALLYTEXTUREDOVERAPORTIONBPABOFITSWIDTHTHETEXTUREDSURFACECONSISTSOFMULTIPLEDIMPLESWITHADIAMETER2RC3P,DEPTHHC3PANDAREADENSITYSPASARESULTOFTHEHYDRODYNAMICPRESSUREGENERATEDBYTHEDIMPLESTHESLIDINGSURFACESWILLBESEPARATEDBYACLEARANCEHC30DEPENDINGONTHESLIDINGVELOCITYU,THEFLUIDVISCOSITYLANDTHEEXTERNALLOADWC3ITWASFOUNDINREF12THATANOPTIMUMRATIOEXISTSFORTHEPARAMETERHPHC3PHC30THATPROVIDESMAXIMUMDIMENSIONLESSLOADCARRYINGCAPACITYWWC3HC302LULB2WHERELISTOWHOMCORRESPONDENCESHOULDBEADDRESSEDEMAILETSIONTXTECHNIONACIL10238883/04/08000295/0C2112004PLENUMPUBLISHINGCORPORATIONTRIBOLOGYLETTERS,VOL17,NO2,AUGUST2004C2112004295THEBEARINGLENGTH,ANDTHISOPTIMUMVALUEISHP125ITWASFURTHERFOUNDINREF12THATANOPTIMUMVALUEEXISTSFORTHETEXTUREDPORTIONADEPENDINGONTHEBEARINGASPECTRATIOL/BTHISBEHAVIORISSHOWNINFIGURE2FORABEARINGWITHL/B075ATVARIOUSVALUESOFTHEAREADENSITYSPASCANBESEENINTHERANGEOFSPVALUESFROM018TO072THEOPTIMUMAVALUEVARIESFROM07TO055,RESPECTIVELYITCANALSOBESEENFROMFIGURE2THATFORA085NOOPTIMUMVALUEEXISTSFORSPANDTHEMAXIMUMLOADWINCREASESWITHINCREASINGSPHENCE,THELARGESTAREADENSITYTHATCANBEPRACTICALLYOBTAINEDWITHTHELASERTEXTURINGISDESIREDITISALSOINTERESTINGTONOTEFROMFIGURE2THEADVANTAGEOFPARTIALLSTA1OVERTHEFULLLSTA1FORBEARINGAPPLICATIONSATSP05,FOREXAMPLE,THELOADWATA06ISABOUTTHREETIMESHIGHERTHANITSVALUEATA1AFULLACCOUNTOFTHISBEHAVIORISGIVENINREF123EXPERIMENTALTHETESTEDBEARINGSCONSISTOFSINTEREDSICDISKS10MMTHICK,HAVING85MMOUTERDIAMETERAND40MMINNERDIAMETEREACHBEARINGSEEFIGURE3COMPRISESAFLATROTORAANDASIXPADSTATORBTHEBEARINGSWEREPROVIDEDWITHANORIGINALSURFACEFINISHBYLAPPINGTOAROUGHNESSAVERAGERA003LMEACHPADHASANASPECTRATIOOF075WHENITSWIDTHISMEASUREDALONGTHEMEANDIAMETEROFTHESTATORTHEPHOTOGRAPHSOFTWOPARTIALLSTSTATORSARESHOWNINFIGURE4WHERETHETEXTUREDAREASAPPEARASBRIGHTERMATTSURFACESTHEFIRSTSTATORINDICATEDAISAUNIDIRECTIONALBEARINGWITHTHEPARTIALLSTADJACENTTOTHELEADINGEDGEOFEACHPAD,SIMILARTOTHEMODELSHOWNINFIGURE1THESECONDSTATORBISABIDIRECTIONALVERSIONOFAPARTIALLSTBEARINGHAVINGTWOEQUALTEXTUREDPORTIONS,A/2,ONEACHOFTHEPADENDSTHELASERTEXTURINGPARAMETERSWERETHEFOLLOWINGDIMPLEDEPTHHC3P65C605LM,DIMPLEDI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优点已被许多厂家所接受。近年来，汽车工业取得了突飞猛进的发展，其产量日益提高。越来越多的消费者也对汽车的性能提出了更高的要求。然而，由于汽车制动缸体的加工属于深孔类加工难度较高，加工工作量较大，二传统的麻花钻又存在着刀具寿命低、加工表面质量差、被加工孔与其它要素之间的位置精度难以保证等诸多不利因素，制动缸体的生产已成为制约汽车产量的难题之一。目前兴起的新型钻枪以其加工质量好，钻屑效率高等优点很好地解决了这个问题。然而由于深孔钻床的特殊性，其价格比较昂贵，对于非专业化厂家，成本过高，而采用普通车床改装成的深孔加工数控钻床。本课题既拟采用C6132改装成一台双工位数控缸体孔钻床。2国内、外现状及发展趋势组合机床是一种高效自动化的专用机床。它与一般的专用机床明显的不同是，组合机床是由大量通用部件、通用零件和少量专用部件所组合而成12。因此，通用部件是组合机床发展的基础。组合机床通用部件是指在组合机床及其自动化设计、制造和使用中，有着统一联系尺寸标准，可以相互更换使用的一些专用部件。这些部件经过试制、试验、鉴定而最后定型，因此它的结构可靠，使用性能稳定3。因此，组合机床通用部件保证了组合机床的质量，降低了成本，缩短了设计制造周期，促进了组合机床的发展。组合机床的通用化程度是衡量组合机床水平的重要标志，具有重要的经济意义。组合机床的通用化程度是指在组合机床的零件总数中，通用零件所占的百分比。目前一般可达到6070，最高可达到90。通用部件直接影响到组合机床及其自动线的自动化水平、加工精度、加工效率以及机床加工工艺方案和经济效益。因此，通用部件应满足下列要求（1）通用部件应具有高的系列化、标准化和通用化水平，增加互换性，扩大通用部件的使用范围。（2）通用部件在性能上应具有先进性，在结构上应具有足够的刚度和精度，以满足各方面加工的需要。（3）通用部件在结构和性能上应满足使用方便、性能稳定、工作可靠、制造容易、维修简单和外形美观等，还要考虑经济性。动力部件要求有适当的变速范围和变速方法。（4）必须提高通用部件的灵活性，以适应各种组合机床及其自动线的要求。（5）必须增加通用部件的品种和规格，以满足生产的发展，如发展适合中小批生产和品种加工组合机床的通用部件。通用部件已经定制为国家标准，并等效于国际标准8。设计时，应贯彻执行国家标准，我国有些企业有内部标准，但其主要技术参数及部件的联系尺寸必须同意执行国家标准，以实现部件通用化目标。枪钻一般是用来钻削工件回转中心上的孔，钻削加工时，通常是工件旋转，钻头作直线进给。枪钻一般是内切削外排屑结构，由硬质合金钻头、钻杆、传动套三部份组成。枪钻钻头上开有油孔，以加强钻头冷却润滑和使切屑顺利排出，并选择韧性和抗振性均较佳的硬质合金作为基体，表面可涂TIC或TIN，以提高钻头的硬度和耐磨性；钻杆一般选用40CR无缝钢管，热处理硬度3545HRC，以提高强度，增加刚性。美国ELDORADO公司对枪钻导向块的布置形式作了大量有成效的试验和研究，该公司认为，工具类型不同，其加工中扭矩特征亦随之变化，当枪钻的切削刃几何参数相同，进给量恒定时，其切削扭矩比较稳定，但随着导向块的结构形状和布置位置不同，其挤压扭矩也随之发生变化。该公司研制的枪钻，结构形式很多，尤其是钻头导向块布置形式与通常的标准型枪钻不同，以五种形状为主，分别适用于钻削钢和不锈钢、钻削有色金属和铸铁、用户机床条件较差、用户要求改善孔径精度和表面粗糙度等场合。ELDORADO公司的枪钻加工深孔的直线度可达0025/300MM，孔径偏差在0013之内，孔表面粗糙度均方根值可达01M14。其生产的枪钻直径为14381MM11/2IN。而德国TBT公司的枪钻钻孔时的径向圆跳动当加工件旋转时可达到一米深的孔为0204MM，加工深孔的直线度可达002004/500MM，孔径偏差根据不同材料而有所不同，一般在IT6IT11之间,孔表面粗糙度RA值也可达01M13。他们生产的枪钻直径为19535MM，并有6种柄部结构形式。同时，TBT公司还生产阶梯枪钻。瑞典SANDVIK公司生产的枪钻直径为19535MM，有12种柄部结构形式，孔径偏差为IT9，孔表面粗糙度RA值为0132M，孔深大于100D，加工深孔的直线度与TBT公司相同。瑞典SANDVIK公司还生产在一般工具磨床上重磨19530MM枪钻的专用装置。德国BOTEK公司生产的枪钻直径为18540MM，双头枪钻和阶梯枪钻直径为432MM，也生产在一般工具磨床上重磨18540MM枪钻的专用装置。孔加工是金属切削加工中最常用的加工工艺。据统计，孔加工的金属切除量约占切削加工总金属切除量的1/3，钻头的产量约占刀具总产量的60。目前用于加工微小孔的工艺方法虽然较多，但应用最广泛、生产实用性最强的仍是采用麻花钻钻削加工6