basis知識(shí)資料of知識(shí)資料welding知識(shí)資料engineering焊接工程基礎(chǔ)

朽木易折，金石可鏤。千里之行，始于足下。第頁/共頁1.Conceptofthewelding焊接概念I(lǐng)nthewayofaddingthepressureatthejointorheatthejointuntilitmelt,forcetheformationofbondingbetweenthetwoseparatesolidmaterialsbecauseoftheformationoftheatomsjoint.在銜接處加壓或加熱至熔融,使兩種分離的固體材料以原子結(jié)合的方式形成銜接.2.Theshapeofthecontactinwelding焊接接觸形狀Differentweldingmethodsinvolveindifferentshapeofcontactbutsomeweldingforexampleshieldedmetalarcweldingcanweldanytypesofjoint不同的焊接主意適用于不同的接觸形狀但是有一些焊接例如手工電弧保護(hù)焊適用于任何的焊接接頭。(1)Squarebuttjoint直對接接頭暗示圖(2)VbuttjointV型對接暗示圖(3)Lapjoint搭接接頭（resistancespotwelding電阻焊;laserbeamwelding激光焊;electronbeamwelding電子束焊）暗示圖(4)TjointT型接頭暗示圖(5)Thecross-sectionofaweldingbuttjoint焊接時(shí)對接截面：fusionzone熔化區(qū)；heat-affectzone熱影響區(qū)；basematerial母材3.Typesofwelding焊接的基本種類和舉例分類（1）fusionwelding熔焊：electricarc電弧焊：1）MIG熔化極氣體保護(hù)焊；2）TIG惰性氣體保護(hù)電弧焊；3）SMAW手工電弧保護(hù)焊。Gaswelding氣焊；laserbeamwelding激光焊（2）pressurewelding壓焊：1）frictionwelding摩擦焊；2）resistancespotwelding電阻焊（3）brazing釬焊1.SMAW(shieldedmetalarcwelding)手工電弧焊:Process：Itisusuallycalled“stick”welding,itisthemostwidelyusedweldingprocess.Whenthearcisstruckbetweenthemetalrodandtheworkpiece,boththerodandtheworkpiecesurfacemelttofromaweldpoor.Atthesametimemeltingofthefluxcoatingontherodwillformgasandslagwhichprotectstheweldpoolfromthesurroundingatmosphere.Theslagwillsolidifyandcoolandmustbechippedofftheweldbeadoncetheweldruniscomplete.手工電弧焊也被稱為焊條焊接，它是焊接中最常見的一種。當(dāng)電弧擊打在金屬焊條和工件之間是，焊條和工件表面同時(shí)都會(huì)產(chǎn)生一個(gè)熔池。同時(shí)籠罩在焊條上的熔化的焊劑會(huì)形成氣體和焊渣，它們保護(hù)焊縫不受周圍氣氛影響。焊渣冷卻后凝結(jié)，所以必須在焊接完成時(shí)及時(shí)清除焊渣。Processcharacteristic：Usearodthatisquicklyconsumed用一根會(huì)消耗很快的焊條Theequipmentissimpleandinexpensive設(shè)備容易成本低Usearodthatprovidesandregulatesitsownflux焊條提供和調(diào)控了其自身的焊劑Provideallpositionflexibility焊接位置靈便Lesssensitivetowindordraft對外界風(fēng)等因素不敏感Thequalitydependsontheoperatorskill質(zhì)量的好壞取決于焊工的技術(shù)暗示圖：Capableofproducingtheweldjoint適用接口：buttjoint對接;lapjoint搭接;t-jointT型接口;filletweld角焊Weldmaterialincludes適用材料包括：mildsteel低碳鋼;castiron鑄鐵;stainlesssteel不銹鋼2.TIG惰性氣體保護(hù)焊：Process：inTIGwelding,anarcisformedbetweenanon-consumabletungstenelectrodeandthemetalbeingwelded.Gasisfedthroughthetorchtoshieldtheelectrodeandmoltenweldpool.Iffillerwireisused,itisaddedtotheweldpoolseparately.在惰性氣體保護(hù)焊中，電弧在無消耗鎢極和被焊接的材料中間形成。氣體通過焊槍進(jìn)入，保護(hù)電極和熔池。倘若要使用焊絲，它需要和焊縫保持距離。暗示圖：AdvantageofTIG:Useanon-consumabletungstenelectrodeduringtheweldingprocess焊接時(shí)使用無消耗的鎢做電極UseanumberofshieldinggasesincludingHeandAr可使用無數(shù)種氣體做保護(hù)氣體包括氦氣和氬氣Easilyappliedtothinmaterials對薄的材料異常適用Produceveryhigh-quality,superiorwelds焊接質(zhì)量異常好Leavesnoslagorsplatter不產(chǎn)生焊渣和飛濺LimitationofTIG:TIGrequiresgreaterwelderdexteritythanMIGorSMAWTIG焊接對焊工的要求比MIG和SMAW更高TIGismorecostlyforweldingthickmetalsection對于厚金屬板焊接，TIG的成本更高Capableofproducingtheweldjoint：similarwithSMAW3.MIG熔化極氣體保護(hù)焊：Process：duringtheMIGweldingprocess,theelectrodemeltswithinthearcandbecomesdepositedasfillermaterial.Theshieldinggasthatisusedpreventsatmosphericfromcontaminationandprotectstheweldduringsolidification.Theshieldgasalsoassistswithstabilizingthearcwhichprovidesasmoothtransferofmetalfromtheweldwiretothemoltenweldpool.在熔化極氣體保護(hù)焊中，電極在電弧作用下熔化并且變成沉積填料。保護(hù)氣體被用于保護(hù)焊接氣氛不受污染并且在焊件凝結(jié)時(shí)起到保護(hù)作用。保護(hù)氣體也起到輔助電弧穩(wěn)定的作用，可以使金屬從焊絲到熔池的改變變得流暢。暗示圖：CharacteristicofMIG:Provideauniformweldbead有一個(gè)勻稱穩(wěn)定的焊縫Produceaslag-freeweldbead不產(chǎn)生焊渣UseashieldinggasusuallyArwith1-5%oxygen;Arwith3-25%co2;combinationArandHegas使用保護(hù)性氣體通常是氬氣和氧氣氬氣和二氧化碳?xì)鍤夂秃釯sconsideredasemi-automaticweldingprocess通?？梢允褂冒胱詣?dòng)化焊接工藝Allowweldinginallposition可以在隨意位置焊接RequirelessoperatorskillthanTIG不需要很高的焊工技術(shù)Allowlongweldstobemadewithoutstartsorstops可以做很長的焊接而不需要中間開始或停止Needlittlecleanup幾乎不需要清掃Capableofproducingtheweldjoint適用接口：buttjoint對接;lapjoint搭接;t-jointT型接口;edgejoint端接接頭暗示圖：Suitableweldingmaterial適用焊接材料：dependsonthedifferenceofshieldgases.Arco2blendsuitformildsteel,aluminum,alloymetal;Hesuitformildsteelinhighspeedprocessandalsocopperandstainlesssteel;carbondioxideismostoftenusedtoweldcarbonandlowalloysteels.按照保護(hù)氣體的不同，適用焊接的材料也不同。氬氣和二氧化碳混合氣體適用于低碳鋼，鋁，合金；氦氣適用于高速工藝中的低碳鋼的焊接和銅及不銹鋼的焊接；二氧化碳適用于