外文翻譯--金屬型鑄造的設(shè)計(jì).doc

金屬型鑄造的設(shè)計(jì)鑄件工藝圖繪制之后，就可進(jìn)行金屬型設(shè)計(jì)。設(shè)計(jì)內(nèi)容主要包括確定金屬型的結(jié)構(gòu)、尺寸、型芯、排氣系統(tǒng)和頂桿機(jī)構(gòu)等。對設(shè)計(jì)的金屬型應(yīng)力求結(jié)構(gòu)簡單，加工方便，選材合理，安全可靠。.金屬型的結(jié)構(gòu)形式一、金屬型的結(jié)構(gòu)形式：金屬型的結(jié)構(gòu)取決于鑄件形狀、尺寸大??；分型面數(shù)量；合金種類和生產(chǎn)批量等條件。按分型面位置，金屬型結(jié)構(gòu)有以下幾種形式：1整體金屬型，鑄型無分型面，結(jié)構(gòu)簡單，但它只適用于形狀簡單，無分型面的鑄件；2水平分型金屬型，它適用于薄壁輪狀鑄件。3垂直分型金屬型，這類金屬型便于開設(shè)澆冒口和排氣系統(tǒng)，開合型方便，容易實(shí)現(xiàn)機(jī)械化生產(chǎn)；多用于生產(chǎn)簡單的小鑄件；4綜合分型金屬型：它由兩個(gè)或兩個(gè)以上的分型面組成，甚至由活塊組成，一般用于復(fù)雜鑄件的生產(chǎn)。操作方便，生產(chǎn)中廣泛采用。二、金屬型主體設(shè)計(jì)：金屬型主體系指構(gòu)成型腔，用于形成鑄件外形的部分。主體結(jié)構(gòu)與鑄件大小，其在型中的澆注位置，分型面以及合金的種類等有關(guān)。在設(shè)計(jì)時(shí)應(yīng)力求使型腔的尺寸準(zhǔn)確；便于開設(shè)澆注系統(tǒng)和排氣系統(tǒng)，鑄件出型方便，有足夠的強(qiáng)度和剛度等。三、金屬型芯的設(shè)計(jì)：根據(jù)鑄件的復(fù)雜情況和合金的種類可采用不同材料的型芯。一般澆注薄壁復(fù)雜件或高熔點(diǎn)合金（如銹鋼、鑄鐵）時(shí)，多采用砂芯，而在澆注低熔點(diǎn)合金（如鋁、鎂合金）時(shí)，大多采用金屬芯。在同一鑄件上也可砂芯和金屬芯并用。四、金屬型的排氣：在設(shè)計(jì)金屬型時(shí)就必須有排氣設(shè)施，其排氣的方式有以下幾種：1利用分型面或型腔零件的組合面的間隙進(jìn)行排氣。2開排氣槽。即在分型面或型腔零件的組合面上，芯座或頂桿表面上做排氣槽。3設(shè)排氣孔。排氣孔一般開設(shè)在金屬型的最高處。4.排氣塞是金屬型常用的排氣設(shè)施五、頂出鑄件機(jī)構(gòu)設(shè)計(jì)金屬型腔的凹凸部分，對鑄件的收縮會(huì)有阻礙，鑄件出型時(shí)就會(huì)有阻力，必須采用頂出機(jī)構(gòu)，方可將鑄件項(xiàng)出。在設(shè)計(jì)頂出機(jī)構(gòu)時(shí)，須注意下面幾點(diǎn)：防止頂傷鑄件，即防止鑄件被頂變形或在鑄件表面頂出凹坑；防止頂桿卡死，首先是頂桿與頂桿孔的配合間隙要適當(dāng)。如果間隙過大易鉆入金屬，過小則可能造成卡死的現(xiàn)象。根據(jù)經(jīng)驗(yàn)最好采用D4dC4級配合。六、金屬型的定位、導(dǎo)向及鎖緊機(jī)構(gòu)金屬型合型時(shí)，要求兩半型定位準(zhǔn)確，、一般采用兩種辦法，即定位銷定位和“止口”定位。對于上下分型，而分型面為圓形時(shí)，可采用“止口”定位，而對于矩形分型面大多采用定位銷定位。定位銷應(yīng)設(shè)在分型面輪廓之內(nèi)，當(dāng)金屬型本身尺寸較大，而自身的重量也較大時(shí)，要保證開合型定位方便，可采導(dǎo)向形式。七、金屬型材料的選擇從金屬型的破壞原因分析可以看到，制造金屬型的材料，應(yīng)消足下列要求：耐熱性和導(dǎo)熱性好，反復(fù)受熱時(shí)不變形，不破壞；應(yīng)具有一定的強(qiáng)度、韌性及耐磨性，機(jī)械加工性好。鑄鐵是金屬型最常用的材料。其加工性能好，價(jià)廉，一般工廠均能自制，并且它又耐熱、耐磨，是一種較合適的金屬型材料。只是在要求高時(shí)，才使用碳鋼和低合金鋼。采用鋁合金制造金屬型，在國外已引起注意，鋁型表面可進(jìn)行陽極氧化處理，而獲得一層由Al2O3及Al2O3H2O組成的氧化膜，其熔點(diǎn)和硬度都較高，而且耐熱、耐磨。據(jù)報(bào)導(dǎo)這種鋁金屬型，如采用水冷措施，它不僅可鑄造鋁件和銅件，同樣也可用來澆注黑色金屬鑄件MetalmoldcastingdesignCastingprocessmapping,canundertakemetaldesign.Designcontentmainlyincludesdeterminingmetalstructure,size,core,exhaustsystemandthetopbarmechanism.Onthedesignofthemetalstresshastheadvantagesofsimplestructure,convenientprocessing,selectionandreasonable,safeandreliable.Metalstructure.Ametaltype,structuralforms:themetalstructuredependsontheshapeofthecasting,thesizeofthenumber；type；typeofalloyandmassproductionconditions.Accordingtothepositionofpartingsurface,metaltypestructurehasthefollowingform:1integralmetaltype,castingnopartingsurface,hastheadvantagesofsimplestructure,butitisonlyapplicabletoasimpleshape,withoutapartingsurfaceofcastings；2levelclassificationofmetaltype,itissuitableforthinwallroundshapedcastings.3verticalmetaltype,thiskindofmetalisconvenientforopeninggatingandexhaustingsystem,openingandclosingtypeconvenient,easyrealizationofmechanizationofproduction；muchusedfortheproductionofsimplesmallcastings；4integratedtypemetaltype:itconsistsoftwoormorethantwopartingsurfacecomposition,evenbyactiveblock,generallyusedforcomplexcastingsproduction.Convenientoperation,widelyusedinproduction.Intwo,metalbodydesign:metaltypemainsystempointstoformacavityforformingthepartshape,casting.Themainstructureandcastingsize,thetypeinthepouringposition,thepartingsurfaceandthealloytypeandotherrelevant.Thedesignshouldstrivetomakethecavitysizeisaccurate；easyopeninggatingsystemandexhaustsystem,castingoutconveniently,hasenoughstrengthandstiffness.Inthree,ametalcoredesign:accordingtothecomplexityofthecastingandthealloyscanbemadeofdifferentmaterialsinthecore.Generalcastingthinwallcomplexorhighmeltingpointalloys(suchasstainlesssteel,castiron),thesandcore,whereasinthecastingoflowmeltingpointalloy(suchasaluminum,magnesiumalloy),mostlywithmetalcore.Inthesamecastingcanalsobethesandcoreandametalcoreandwiththe.Infour,metaltypeexhaust:inthedesignofmetaltypemusthaveexhaustfacility,itsexhaustinthefollowingways:1theuseofsurfaceorcavitycombinationofpartssurfacegapdischarge.2openairvent.Thepartingsurfaceorcavitycombinationofpartssurface,coreseatorthetoprodsurfaceonexhaustgroove.3providedwithanexhausthole.Exhaustholeopenedinthegeneralmetaltop.The4exhaustplugiscommonlyusedmetaltypeexhaustfacilityFive,topcastingmechanismdesignofmetalcavityoftheconcaveandconvexportions,theshrinkageofthecastingwillbehindered,castingouttherewillberesistance,mustadopttheejectionmechanism,wecancasta.Inthedesignoftheejectionmechanism,mustpayattentiontothefollowingseveralpoints:preventgoringcastings,i.e.preventingcastingsaretopdeformationorinthecastingsurfacetoppit；preventingthetoproddeathcard,firstisthetoprodandthetoprodholeclearanceshouldbeappropriate.Iftheclearanceistoolarge,easytodrillintothemetal,istoosmallmaycausethelockingphenomenon.AccordingtotheexperienceofusingD4/dC4withthebest.Insix,metaltypepositioning,guidingandlockingmechanismofmetaltypemold,requirementsintwotypepositioningaccuracy,ingeneral,theuseoftwomethods,namelythepositioningofthepinandthepositioningofstop.Forthenextminute,whereasthepartingsurfaceiscircular,withstopposition,andfortherectangulartypesurfacemostlyadoptsthepositioningpin.Thepositioningpinshouldbelocatedinthepartingsurfacecontour,whenthemetaltypeitselfislargeinsize,anditsweightisalsobig,toensuretheopen-closelocationconvenient,recoverableorientedform.Inseven,metalmoldmaterialselectionFromthemetaldamagecauseanalysiscansee,manufacturingmetalmoldmaterial,shouldeliminatefootthefollowingrequirements:heatresistanceandgoodthermalconductivity,repeatedheatingwithoutdeformation,nodamage；shouldhaveacertainstrength,toughnessandwearresistance,goodmachinability.Castironisametaltypemostcommonlyusedmaterial.Itsprocessingperformance,lowcost,generalfactorycanbemade,anditisresistanttoheat,abrasion,isakindofmoresuitablemetalmaterial.Onlyinthehigh,tousecarbonsteelandlowalloysteel.Madeofaluminumalloymetaltype,inforeigncountrieshasattractedattention,aluminumsurfacecanbeanodized,andobtainalayerconsistsofAl2