焊接與銀釬焊SOLDERINGANDSILVERBRAZING

務(wù)必記住所推薦的閥門的用途是什么，并對(duì)所應(yīng)用的環(huán)境進(jìn)行分析，這樣才能決定選用最適合安裝什么樣的閥門。在安裝正確的閥門之前，為了防止損壞閥門，并保證充分發(fā)揮閥門的工作性能，請(qǐng)閱讀一下安裝指南：Analyzetheapplicationtodeterminewhichvalveisbestsuitedforinstallations,keepinginmindtheserviceforwhichthevalveisrecommended.Beforeinstallingthecorrectvalve,reviewtheinstallationinstructionstopreventdamagetothevalveandtoassureitsmaximumefficiency：

先沿著垂直方向切割管道，并修整、去除毛刺，測(cè)量管徑。Cuttubeendsquare.Ream,burrandsize.

使用紗布或鋼絲刷清除管道和切割部位，使其金屬表面發(fā)光發(fā)亮。建議不要使用鋼絲絨。Usesandclothorsteelwirebrushtocleanbothendstoabrightmetalfinish.Steelwoolisnotrecommended.

在管道的外面和焊接罩的內(nèi)部涂上焊劑，焊劑必須完全覆蓋焊接表面。請(qǐng)有節(jié)制地使用焊劑。Applyfluxtooutsideoftubeandinsideofsoldercup.Surfacestobejoinedmustbecompletelycovered.Usefluxsparingly.

要確保閥門處于開(kāi)啟狀態(tài)。先對(duì)管道加熱。盡可能多的將熱從管道傳遞到閥門。避免延長(zhǎng)閥門本身的加熱時(shí)間。Besurethatvalveisfullyopen.Applyheattotubefirst.Transferasmuchheataspossiblethroughtubeintovalve.Avoidprolongedheatingofvalveitself.

銀釬焊的方法：對(duì)需要進(jìn)行釬焊的部件進(jìn)行組裝。如果允許涂上焊劑的部件處于直立狀態(tài)，那么焊劑中的水分會(huì)蒸發(fā)掉，而干燥的焊劑很容易脫落，致使暴露的金屬表面容易被氧化。在進(jìn)行連接組裝時(shí)，要將管道插入管套直到遇到阻擋為止。組裝是要保證有穩(wěn)固的支撐，使得整個(gè)釬焊操作過(guò)程中能夠保持在直線位置。SilverBrazingMethod:Assemblepartstobebrazed.Iffluxedpartsareallowedtostand,thewaterinthefluxwillevaporate,anddriedfluxisliabletoflakeoff,exposingmetalsurfacestooxidation.Assemblejointbyinsertingtubeintosockethardagainstthestop.Theassemblyshouldbefirmlysupportedsothatitwillremaininalignmentduringthebrazingoperation.

注：對(duì)于1英寸或更大公稱通徑的閥門，一次性將連接部件加熱到所需溫度比較困難。為了在整個(gè)大面積上保持正常的溫度，通常情況下需要兩個(gè)焊槍。建議對(duì)整個(gè)管套區(qū)域進(jìn)行適當(dāng)?shù)念A(yù)熱。建議采用乙炔火焰對(duì)連接部件進(jìn)行加熱。首先從離閥門1英寸的地方開(kāi)始對(duì)管道進(jìn)行加熱，然后圍繞著管道短距離上下交替對(duì)管道進(jìn)行火焰烘烤，并以適當(dāng)?shù)慕嵌刃�轉(zhuǎn)管道，避免燒穿管道�；鹧嬉�連續(xù)運(yùn)動(dòng)，不允許停留在某一點(diǎn)上。NOTE:Onone-inchandlargervalves,itisdifficulttobringthewholejointuptotemperatureatonetime.Itwillfrequentlybefounddesirabletouseadouble-tiptorchtomaintainthepropertemperatureoverthelargerarea.Amildpre-heatingofthewholesocketareaisrecommended.Applyheattopartstobejoined.Thepreferredmethodisbyoxy-acetyleneflame.Heattubefirst,beginningoneinchfromedgeofvalve.Sweepflamearoundtubeinshortstrokesupanddownatrightanglestorunoftube.Toavoidburningthroughtube,theflameshouldbeincontinuousmotionandnotallowedtoremainonanyonepoint.

在閥門的套筒底座用火焰進(jìn)行烘烤。加熱要均勻，用火焰對(duì)閥門及管道進(jìn)行火焰烘烤的過(guò)程要延續(xù)到閥門上的焊劑不再發(fā)出聲音。不要對(duì)閥門過(guò)度加熱。Applyflametovalveatbaseofsocket.Heatuniformly,sweepingflamefromvalvetotubeuntilfluxonvalvebecomesquiet.Avoidexcessiveheatingofvalve.

當(dāng)焊劑變成液態(tài)并且在管道和閥門上呈現(xiàn)半透明狀態(tài)時(shí)，開(kāi)始將火焰沿著連接部件的軸線進(jìn)行進(jìn)退烘烤，以保持連接部件、特別是閥門套筒底座部位的熱度。Whenfluxappearsliquidandtransparentonbothtubeandvalve,startsweepingflamebackandforthalongaxisofjointtomaintainheatonpartstobejoined,especiallytowardbaseofvalvesocket.

使用適量的焊料：如果使用線狀焊料，那么對(duì)公稱通徑為3/4英寸的閥門就要采用3/4英寸的焊料，等等。如果使用的焊料太多，那么有些焊料可能會(huì)流過(guò)管道阻擋部位，并堵塞密封區(qū)域。在安裝連接部件時(shí)，可以看到焊料和釬焊合金繼續(xù)流動(dòng)Usejustenoughsolder:withwiresolder,use3/4"fora3/4"valve,etc.Iftoomuchsolderisused,itmayflowpasttubestopandclogsealingarea.Whenjointisfilled,acontinuousrunofsolderorbrazingalloywillbevisible.

銀釬焊法：將焊線或焊桿點(diǎn)在閥門里的管道套座上。當(dāng)焊桿或焊線進(jìn)入連接處時(shí)要將火焰從其上面移開(kāi)。當(dāng)合金流進(jìn)連接處時(shí)，要前后移動(dòng)火焰。達(dá)到適當(dāng)?shù)臏囟群�，合金將迅速容易地流進(jìn)管道外殼和閥門套管之間的空間。連接處被充滿后，就會(huì)看到焊接合金的邊緣。SilverBrazingMethod:Applybrazingwireorrodatpointwheretubeentersvalvesocket.Keepflameawayfromrodorwireasitisfedintothejoint.Moveflamebackandforthasalloyisdrawnintojoint.Whenthepropertemperatureisreachedalloywillflowreadilyintospacebetweentubeouterwallandvalvesocket.Whenjointisfilled,acontinuousrimofbrazingalloywillbevisible.