摘要：<span style="font-family:宋體;font-size:small;"> </span> <p style="margin:0cm 0cm 0pt;"> <span style="font-family:宋體;mso-ascii-font-family:&quot;Times New Roman&quot;;mso-hansi-font-family:&quot;Times New Roman&quot;;"><span style="font-size:small;">西安雙相不鏽鋼管的焊接要求</span></span> </p> <span style="font-family:宋體;font-size:small;"> </span> <p style="margin:0cm 0cm 0pt;"> <span style="font-size:small;"><span style="font-family:宋體;mso-ascii-font-family:&quot;Times New Roman&quot;;mso-hansi-font-family:&quot;Times New Roman&quot;;">在石油化工裝置中一種新型鋼材</span><span style="font-family:'Times New Roman';"><span lang="EN-US">-</span></span><span style="font-family:宋體;mso-ascii-font-family:&quot;Times New Roman&quot;;mso-hansi-font-family:&quot;Times New Roman&quot;;">雙相不鏽鋼的應(yīng)用越來(lái)越多。因?yàn)殡p相不鏽鋼的屈服強(qiáng)度是普通不鏽鋼的</span><span style="font-family:'Times New Roman';"><span lang="EN-US">2</span></span><span style="font-family:宋體;mso-ascii-font-family:&quot;Times New Roman&quot;;mso-hansi-font-family:&quot;Times New Roman&quot;;">倍，抗腐蝕性能（特彆是在腐蝕性介質(zhì)中）明顯優(yōu)於普通不鏽鋼，在石油化工裝置施工中多用在很重要的位置。因此，一般雙相不鏽鋼的焊縫要求</span><span style="font-family:'Times New Roman';"><span lang="EN-US">100%RT</span></span><span style="font-family:宋體;mso-ascii-font-family:&quot;Times New Roman&quot;;mso-hansi-font-family:&quot;Times New Roman&quot;;">檢驗(yàn)，對(duì)其焊接接頭的綜合性能的要求也高於一般奧氏體不鏽鋼。所以，必須選派焊接經(jīng)驗(yàn)豐富的奧氏體不鏽鋼焊工，經(jīng)培訓(xùn)和考試合格後，才能持證上崗進(jìn)行焊接作業(yè)。</span></span><span lang="EN-US"><br /> <span style="font-family:'Times New Roman';font-size:small;"> 1&nbsp; &nbsp; </span></span><span style="font-family:宋體;mso-ascii-font-family:&quot;Times New Roman&quot;;mso-hansi-font-family:&quot;Times New Roman&quot;;"><span style="font-size:small;">焊接性分析</span></span><span lang="EN-US"><br /> <span style="font-family:'Times New Roman';font-size:small;"> </span></span><span style="font-size:small;"><span style="font-family:宋體;mso-ascii-font-family:&quot;Times New Roman&quot;;mso-hansi-font-family:&quot;Times New Roman&quot;;">雙相不鏽鋼焊接時(shí)，焊接熱影響區(qū)（</span><span style="font-family:'Times New Roman';"><span lang="EN-US">HAZ</span></span><span style="font-family:宋體;mso-ascii-font-family:&quot;Times New Roman&quot;;mso-hansi-font-family:&quot;Times New Roman&quot;;">）</span></span><span style="font-family:'Times New Roman';font-size:small;"> </span><span style="font-size:small;"><span style="font-family:宋體;mso-ascii-font-family:&quot;Times New Roman&quot;;mso-hansi-font-family:&quot;Times New Roman&quot;;">存在高溫區(qū)和低溫區(qū)，低溫區(qū)基本處?kù)?lt;/span><span style="font-family:'Times New Roman';"><span lang="EN-US">δ+γ</span></span><span style="font-family:宋體;mso-ascii-font-family:&quot;Times New Roman&quot;;mso-hansi-font-family:&quot;Times New Roman&quot;;">（鐵素體</span><span style="font-family:'Times New Roman';"><span lang="EN-US">+</span></span><span style="font-family:宋體;mso-ascii-font-family:&quot;Times New Roman&quot;;mso-hansi-font-family:&quot;Times New Roman&quot;;">奧氏體）平衡組織，而高溫區(qū)幾乎為單相</span><span style="font-family:'Times New Roman';"><span lang="EN-US">δ</span></span><span style="font-family:宋體;mso-ascii-font-family:&quot;Times New Roman&quot;;mso-hansi-font-family:&quot;Times New Roman&quot;;">組織，因?yàn)楹缚p根部和表麵</span><span style="font-family:'Times New Roman';"><span lang="EN-US">N</span></span><span style="font-family:宋體;mso-ascii-font-family:&quot;Times New Roman&quot;;mso-hansi-font-family:&quot;Times New Roman&quot;;">的擴(kuò)散，導(dǎo)致靠近焊縫表麵的部位，由於</span><span style="font-family:'Times New Roman';"><span lang="EN-US">N</span></span><span style="font-family:宋體;mso-ascii-font-family:&quot;Times New Roman&quot;;mso-hansi-font-family:&quot;Times New Roman&quot;;">的損失，鐵素體增加，從而促進(jìn)氮化物的產(chǎn)生，使焊接接頭性能惡化，焊接采用高線(xiàn)能量時(shí)，可以得到較多的</span><span style="font-family:'Times New Roman';"><span lang="EN-US">γ</span></span><span style="font-family:宋體;mso-ascii-font-family:&quot;Times New Roman&quot;;mso-hansi-font-family:&quot;Times New Roman&quot;;">相，鐵素體含量低會(huì)促進(jìn)</span><span style="font-family:'Times New Roman';"><span lang="EN-US">δ</span></span><span style="font-family:宋體;mso-ascii-font-family:&quot;Times New Roman&quot;;mso-hansi-font-family:&quot;Times New Roman&quot;;">相產(chǎn)生，所以容易產(chǎn)生</span><span style="font-family:'Times New Roman';"><span lang="EN-US">δ</span></span><span style="font-family:宋體;mso-ascii-font-family:&quot;Times New Roman&quot;;mso-hansi-font-family:&quot;Times New Roman&quot;;">相和粗晶組織；線(xiàn)能量較低時(shí)，得不到足夠的</span><span style="font-family:'Times New Roman';"><span lang="EN-US">γ</span></span><span style="font-family:宋體;mso-ascii-font-family:&quot;Times New Roman&quot;;mso-hansi-font-family:&quot;Times New Roman&quot;;">相。如果焊接金屬中</span><span style="font-family:'Times New Roman';"><span lang="EN-US">δ</span></span><span style="font-family:宋體;mso-ascii-font-family:&quot;Times New Roman&quot;;mso-hansi-font-family:&quot;Times New Roman&quot;;">相過(guò)多，</span><span style="font-family:'Times New Roman';"><span lang="EN-US">N</span></span><span style="font-family:宋體;mso-ascii-font-family:&quot;Times New Roman&quot;;mso-hansi-font-family:&quot;Times New Roman&quot;;">很容易與</span><span style="font-family:'Times New Roman';"><span lang="EN-US">cγ</span></span><span style="font-family:宋體;mso-ascii-font-family:&quot;Times New Roman&quot;;mso-hansi-font-family:&quot;Times New Roman&quot;;">形成化合物，而且析出二次</span><span style="font-family:'Times New Roman';"><span lang="EN-US">γ</span></span><span style="font-family:宋體;mso-ascii-font-family:&quot;Times New Roman&quot;;mso-hansi-font-family:&quot;Times New Roman&quot;;">變?yōu)獒槧詈陀鹈珷睿哂形菏象w組織特性，導(dǎo)致焊接接頭力學(xué)性能和耐腐蝕性下降。雙相鋼一般不會(huì)產(chǎn)生</span><span style="font-family:'Times New Roman';"><span lang="EN-US">δ</span></span><span style="font-family:宋體;mso-ascii-font-family:&quot;Times New Roman&quot;;mso-hansi-font-family:&quot;Times New Roman&quot;;">相，但如果焊接線(xiàn)能量較高，導(dǎo)致使焊接頭塑性大幅度下降。</span></span><span lang="EN-US"><br /> <span style="font-family:'Times New Roman';font-size:small;"> 2&nbsp; &nbsp; </span></span><span style="font-family:宋體;mso-ascii-font-family:&quot;Times New Roman&quot;;mso-hansi-font-family:&quot;Times New Roman&quot;;"><span style="font-size:small;">焊接工藝</span></span><span lang="EN-US"><br /> <span style="font-family:'Times New Roman';font-size:small;"> 2.1&nbsp; &nbsp; </span></span><span style="font-size:small;"><span style="font-family:宋體;mso-ascii-font-family:&quot;Times New Roman&quot;;mso-hansi-font-family:&quot;Times New Roman&quot;;">工藝參數(shù)及電特性（見(jiàn)表</span><span style="font-family:'Times New Roman';"><span lang="EN-US">2</span></span><span style="font-family:宋體;mso-ascii-font-family:&quot;Times New Roman&quot;;mso-hansi-font-family:&quot;Times New Roman&quot;;">）</span></span><span lang="EN-US"><br /> <span style="font-family:'Times New Roman';font-size:small;"> 2.2&nbsp; &nbsp; </span></span><span style="font-family:宋體;mso-ascii-font-family:&quot;Times New Roman&quot;;mso-hansi-font-family:&quot;Times New Roman&quot;;"><span style="font-size:small;">焊接方法</span></span><span lang="EN-US"><br /> <span style="font-family:'Times New Roman';font-size:small;"> </span></span><span style="font-size:small;"><span style="font-family:宋體;mso-ascii-font-family:&quot;Times New Roman&quot;;mso-hansi-font-family:&quot;Times New Roman&quot;;">雙相不鏽鋼薄壁管全部采用</span><span style="font-family:'Times New Roman';"><span lang="EN-US">GTAW</span></span><span style="font-family:宋體;mso-ascii-font-family:&quot;Times New Roman&quot;;mso-hansi-font-family:&quot;Times New Roman&quot;;">焊接，直流正極性。</span></span><span lang="EN-US"><br /> <span style="font-family:'Times New Roman';font-size:small;"> 2.3&nbsp; &nbsp; </span></span><span style="font-family:宋體;mso-ascii-font-family:&quot;Times New Roman&quot;;mso-hansi-font-family:&quot;Times New Roman&quot;;"><span style="font-size:small;">焊接設(shè)備</span></span><span lang="EN-US"><br /> <span style="font-family:'Times New Roman';font-size:small;"> </span></span><span style="font-size:small;"><span style="font-family:宋體;mso-ascii-font-family:&quot;Times New Roman&quot;;mso-hansi-font-family:&quot;Times New Roman&quot;;">焊機(jī)采用高頻引弧焊機(jī)，直流正極性，鎢極直徑</span><span style="font-family:'Times New Roman';"><span lang="EN-US">Φ2.5mm</span></span><span style="font-family:宋體;mso-ascii-font-family:&quot;Times New Roman&quot;;mso-hansi-font-family:&quot;Times New Roman&quot;;">，鎢極端頭用磨光機(jī)磨出錐形，采用大噴嘴。</span></span><span lang="EN-US"><br /> <span style="font-family:'Times New Roman';font-size:small;"> 2.4&nbsp; &nbsp; </span></span><span style="font-family:宋體;mso-ascii-font-family:&quot;Times New Roman&quot;;mso-hansi-font-family:&quot;Times New Roman&quot;;"><span style="font-size:small;">氣體保護(hù)</span></span><span lang="EN-US"><br /> <span style="font-family:'Times New Roman';font-size:small;"> </span></span><span style="font-size:small;"><span style="font-family:宋體;mso-ascii-font-family:&quot;Times New Roman&quot;;mso-hansi-font-family:&quot;Times New Roman&quot;;">焊接保護(hù)氣體采用混合氣體</span><span style="font-family:'Times New Roman';"><span lang="EN-US">Ar97.5%+N2.5% </span></span><span style="font-family:宋體;mso-ascii-font-family:&quot;Times New Roman&quot;;mso-hansi-font-family:&quot;Times New Roman&quot;;">進(jìn)行保護(hù)，保護(hù)氣采用成品混合氣，要求生產(chǎn)的成品混合比為</span><span style="font-family:'Times New Roman';"><span lang="EN-US">Ar97.5%+N2.5%</span></span><span style="font-family:宋體;mso-ascii-font-family:&quot;Times New Roman&quot;;mso-hansi-font-family:&quot;Times New Roman&quot;;">，由於混合氣體中</span><span style="font-family:'Times New Roman';"><span lang="EN-US">Ar</span></span><span style="font-family:宋體;mso-ascii-font-family:&quot;Times New Roman&quot;;mso-hansi-font-family:&quot;Times New Roman&quot;;">比</span><span style="font-family:'Times New Roman';"><span lang="EN-US">N</span></span><span style="font-family:宋體;mso-ascii-font-family:&quot;Times New Roman&quot;;mso-hansi-font-family:&quot;Times New Roman&quot;;">多，放置一段時(shí)間後將會(huì)產(chǎn)生分層，影響氣體保護(hù)效果，現(xiàn)場(chǎng)所采用搖勺或加氣體分配器進(jìn)行配比，確保氣體保護(hù)質(zhì)量。</span></span><span lang="EN-US"><br /> <span style="font-family:'Times New Roman';font-size:small;"> 2.5&nbsp; &nbsp; </span></span><span style="font-family:宋體;mso-ascii-font-family:&quot;Times New Roman&quot;;mso-hansi-font-family:&quot;Times New Roman&quot;;"><span style="font-size:small;">環(huán)境要求</span></span><span lang="EN-US"><br /> <span style="font-family:'Times New Roman';font-size:small;"> </span></span><span style="font-size:small;"><span style="font-family:宋體;mso-ascii-font-family:&quot;Times New Roman&quot;;mso-hansi-font-family:&quot;Times New Roman&quot;;">雙相不鏽鋼焊接要求環(huán)境清潔。無(wú)鐵離子汙染，預(yù)置工作將在室內(nèi)進(jìn)行，地麵采用膠皮隔離、安裝必須做好環(huán)境保護(hù)。采用防風(fēng)防塵設(shè)施，環(huán)境溫度</span><span style="font-family:'Times New Roman';"><span lang="EN-US">70</span></span><span style="font-family:宋體;mso-ascii-font-family:&quot;Times New Roman&quot;;mso-hansi-font-family:&quot;Times New Roman&quot;;">℃，相對(duì)溫度</span><span style="font-family:'Times New Roman';"><span lang="EN-US">≤90%</span></span><span style="font-family:宋體;mso-ascii-font-family:&quot;Times New Roman&quot;;mso-hansi-font-family:&quot;Times New Roman&quot;;">，所有與雙相鋼焊接坡口相接觸的，如：焊材、工具、手套等，都必須無(wú)鐵鏽汙染。坡口均采用坡口機(jī)加工，坡口角度為單邊</span><span style="font-family:'Times New Roman';"><span lang="EN-US">30°±2.5°</span></span><span style="font-family:宋體;mso-ascii-font-family:&quot;Times New Roman&quot;;mso-hansi-font-family:&quot;Times New Roman&quot;;">，鈍邊</span><span style="font-family:'Times New Roman';"><span lang="EN-US">0~ 0.5mm</span></span><span style="font-family:宋體;mso-ascii-font-family:&quot;Times New Roman&quot;;mso-hansi-font-family:&quot;Times New Roman&quot;;">，單麵坡口（見(jiàn)附圖），加工坡口不允許母材產(chǎn)生過(guò)燒變色；其兩側(cè)各</span><span style="font-family:'Times New Roman';"><span lang="EN-US">50mm</span></span><span style="font-family:宋體;mso-ascii-font-family:&quot;Times New Roman&quot;;mso-hansi-font-family:&quot;Times New Roman&quot;;">以?xún)?nèi)的內(nèi)外表麵要進(jìn)行嚴(yán)格清理，清理程序是磨光機(jī)打磨、丙酮（或無(wú)水乙醇）清洗，清洗後不能直接進(jìn)行焊接作業(yè)，待坡口端麵晾乾後方可焊接作業(yè)；焊絲也用沾丙酮（或無(wú)水乙醇）的海綿擦拭乾淨(jìng)。對(duì)鐵離子、水鏽、油、灰塵、油漆、記號(hào)筆印都必須清理乾淨(jìng)，防止其影響化學(xué)成份和機(jī)械性能。另外，還要注意坡口形狀必須無(wú)凹凸和劃痕，這樣焊接時(shí)電弧在焊道的每一點(diǎn)上都能保證停留相同的時(shí)間，焊接線(xiàn)能量才能確保一致。</span></span><span lang="EN-US"><br /> <span style="font-family:'Times New Roman';font-size:small;"> 2.6&nbsp; &nbsp; </span></span><span style="font-family:宋體;mso-ascii-font-family:&quot;Times New Roman&quot;;mso-hansi-font-family:&quot;Times New Roman&quot;;"><span style="font-size:small;">焊接措施</span></span><span lang="EN-US"><br /> <span style="font-family:'Times New Roman';font-size:small;"> </span></span><span style="font-size:small;"><span style="font-family:宋體;mso-ascii-font-family:&quot;Times New Roman&quot;;mso-hansi-font-family:&quot;Times New Roman&quot;;">儘量采用多層焊，因?yàn)獒崂m(xù)焊道對(duì)前層焊道有熱處理作用，焊縫中的</span><span style="font-family:'Times New Roman';"><span lang="EN-US">δ</span></span><span style="font-family:宋體;mso-ascii-font-family:&quot;Times New Roman&quot;;mso-hansi-font-family:&quot;Times New Roman&quot;;">相進(jìn)一步轉(zhuǎn)化為</span><span style="font-family:'Times New Roman';"><span lang="EN-US">γ</span></span><span style="font-family:宋體;mso-ascii-font-family:&quot;Times New Roman&quot;;mso-hansi-font-family:&quot;Times New Roman&quot;;">相，使焊接接頭的組織和性能顯著改善，而後一道焊縫處?kù)斗枪ぷ鹘橘|(zhì)麵，因?yàn)閷?duì)焊接接頭影響不大，保護(hù)氣采用</span><span style="font-family:'Times New Roman';"><span lang="EN-US">Ar97.5%+N2.5%</span></span><span style="font-family:宋體;mso-ascii-font-family:&quot;Times New Roman&quot;;mso-hansi-font-family:&quot;Times New Roman&quot;;">。因?yàn)楹附痈勘Ｗo(hù)氣體中加氮?dú)庠黾雍缚p金屬氮量，由於采用多層焊工藝，焊接材料中含</span><span style="font-family:'Times New Roman';"><span lang="EN-US">N</span></span><span style="font-family:宋體;mso-ascii-font-family:&quot;Times New Roman&quot;;mso-hansi-font-family:&quot;Times New Roman&quot;;">量與母材相當(dāng)，而後一道焊縫處?kù)斗枪ぷ鹘橘|(zhì)麵，因?yàn)閷?duì)焊接接頭影響不大，采用合適的線(xiàn)能量焊接，使焊接接頭得到足夠的</span><span style="font-family:'Times New Roman';"><span lang="EN-US">γ</span></span><span style="font-family:宋體;mso-ascii-font-family:&quot;Times New Roman&quot;;mso-hansi-font-family:&quot;Times New Roman&quot;;">相，使</span><span style="font-family:'Times New Roman';"><span lang="EN-US">Cγ</span></span><span style="font-family:宋體;mso-ascii-font-family:&quot;Times New Roman&quot;;mso-hansi-font-family:&quot;Times New Roman&quot;;">、</span><span style="font-family:'Times New Roman';"><span lang="EN-US">N1 </span></span><span style="font-family:宋體;mso-ascii-font-family:&quot;Times New Roman&quot;;mso-hansi-font-family:&quot;Times New Roman&quot;;">和</span><span style="font-family:'Times New Roman';"><span lang="EN-US">M</span></span><span style="font-family:宋體;mso-ascii-font-family:&quot;Times New Roman&quot;;mso-hansi-font-family:&quot;Times New Roman&quot;;">有足夠的時(shí)間擴(kuò)散。</span></span><span lang="EN-US"><br /> <span style="font-family:'Times New Roman';font-size:small;"> 2.7&nbsp; &nbsp; </span></span><span style="font-family:宋體;mso-ascii-font-family:&quot;Times New Roman&quot;;mso-hansi-font-family:&quot;Times New Roman&quot;;"><span style="font-size:small;">坡口的組對(duì)及點(diǎn)焊</span></span><span lang="EN-US"><br /> <span style="font-family:'Times New Roman';font-size:small;"> </span></span><span style="font-size:small;"><span style="font-family:宋體;mso-ascii-font-family:&quot;Times New Roman&quot;;mso-hansi-font-family:&quot;Times New Roman&quot;;">坡口組對(duì)前應(yīng)仔細(xì)檢查坡口管徑是否相同，錯(cuò)邊應(yīng)控製在</span><span style="font-family:'Times New Roman';"><span lang="EN-US">0.5~1mm</span></span><span style="font-family:宋體;mso-ascii-font-family:&quot;Times New Roman&quot;;mso-hansi-font-family:&quot;Times New Roman&quot;;">之間，並用磨光機(jī)打磨清理坡口及坡口正反麵兩側(cè)</span><span style="font-family:'Times New Roman';"><span lang="EN-US">50mm</span></span><span style="font-family:宋體;mso-ascii-font-family:&quot;Times New Roman&quot;;mso-hansi-font-family:&quot;Times New Roman&quot;;">以?xún)?nèi)的表麵，並用丙酮擦試乾淨(jìng)，坡口打磨時(shí)不允許使母材產(chǎn)生過(guò)熱變色。點(diǎn)焊時(shí)，應(yīng)采用與正式的焊接工藝相同的參數(shù)，點(diǎn)焊長(zhǎng)度為</span><span style="font-family:'Times New Roman';"><span lang="EN-US">7~8mm</span></span><span style="font-family:宋體;mso-ascii-font-family:&quot;Times New Roman&quot;;mso-hansi-font-family:&quot;Times New Roman&quot;;">，高度為</span><span style="font-family:'Times New Roman';"><span lang="EN-US">2~ 3mm</span></span><span style="font-family:宋體;mso-ascii-font-family:&quot;Times New Roman&quot;;mso-hansi-font-family:&quot;Times New Roman&quot;;">，點(diǎn)焊點(diǎn)應(yīng)為過(guò)橋型式，不應(yīng)焊透，以防內(nèi)部氧化，點(diǎn)焊電流不宜過(guò)大，點(diǎn)焊點(diǎn)位置應(yīng)在組對(duì)管子的上部及兩側(cè)，點(diǎn)固三點(diǎn)，從第四點(diǎn)起焊，當(dāng)焊到點(diǎn)焊時(shí)，將點(diǎn)固點(diǎn)打磨清理乾淨(jìng)，焊縫組對(duì)間隙應(yīng)控製在</span><span style="font-family:'Times New Roman';"><span lang="EN-US">2~2.5mm</span></span><span style="font-family:宋體;mso-ascii-font-family:&quot;Times New Roman&quot;;mso-hansi-font-family:&quot;Times New Roman&quot;;">，間隙不應(yīng)過(guò)大，並留有</span><span style="font-family:'Times New Roman';"><span lang="EN-US">0~0.5mm</span></span><span style="font-family:宋體;mso-ascii-font-family:&quot;Times New Roman&quot;;mso-hansi-font-family:&quot;Times New Roman&quot;;">的鈍邊。</span></span><span lang="EN-US"><br /> <span style="font-family:'Times New Roman';font-size:small;"> 2.8&nbsp; &nbsp; </span></span><span style="font-family:宋體;mso-ascii-font-family:&quot;Times New Roman&quot;;mso-hansi-font-family:&quot;Times New Roman&quot;;"><span style="font-size:small;">雙相不鏽鋼的焊接操作</span></span><span lang="EN-US"><br /> <span style="font-family:'Times New Roman';font-size:small;"> </span></span><span style="font-size:small;"><span style="font-family:宋體;mso-ascii-font-family:&quot;Times New Roman&quot;;mso-hansi-font-family:&quot;Times New Roman&quot;;">雙相不鏽鋼焊接時(shí)，應(yīng)采用正反麵氣體保護(hù)焊，正麵背麵都應(yīng)采用混合氣體</span><span style="font-family:'Times New Roman';"><span lang="EN-US">Ar97.5%+N2.5% </span></span><span style="font-family:宋體;mso-ascii-font-family:&quot;Times New Roman&quot;;mso-hansi-font-family:&quot;Times New Roman&quot;;">進(jìn)行保護(hù)，焊接前不得在焊件表麵引弧和試驗(yàn)電流，焊接時(shí)應(yīng)按指定的焊接作業(yè)指導(dǎo)書(shū)進(jìn)行施焊。在焊接前，管子兩端用布或膠皮封好，並留有進(jìn)氣孔和排氣孔，焊縫間隙用膠布貼好，並留有</span><span style="font-family:'Times New Roman';"><span lang="EN-US">20~30mm</span></span><span style="font-family:宋體;mso-ascii-font-family:&quot;Times New Roman&quot;;mso-hansi-font-family:&quot;Times New Roman&quot;;">的長(zhǎng)度，使管子內(nèi)部的空氣能夠排出，確保焊縫內(nèi)部的氣體保護(hù)效果。焊接時(shí)，焊槍不宜擺動(dòng)，手法要穩(wěn)，嚴(yán)格控製線(xiàn)能量，儘量采用小焊絲，嚴(yán)格控製電流，弧長(zhǎng)儘量壓低控製電壓，儘量用大噴嘴，提高氣體保護(hù)效果，降底</span><span style="font-family:'Times New Roman';"><span lang="EN-US">O</span></span><span style="font-family:宋體;mso-ascii-font-family:&quot;Times New Roman&quot;;mso-hansi-font-family:&quot;Times New Roman&quot;;">、</span><span style="font-family:'Times New Roman';"><span lang="EN-US">H</span></span><span style="font-family:宋體;mso-ascii-font-family:&quot;Times New Roman&quot;;mso-hansi-font-family:&quot;Times New Roman&quot;;">汙染；引、收弧避開(kāi)點(diǎn)焊點(diǎn)，防止產(chǎn)生二次</span><span style="font-family:'Times New Roman';"><span lang="EN-US">γ</span></span><span style="font-family:宋體;mso-ascii-font-family:&quot;Times New Roman&quot;;mso-hansi-font-family:&quot;Times New Roman&quot;;">和</span><span style="font-family:'Times New Roman';"><span lang="EN-US">δ</span></span><span style="font-family:宋體;mso-ascii-font-family:&quot;Times New Roman&quot;;mso-hansi-font-family:&quot;Times New Roman&quot;;">相，引弧點(diǎn)必須在焊道內(nèi)進(jìn)行，不能在母材表麵引弧，防止</span><span style="font-family:'Times New Roman';"><span lang="EN-US">F</span></span><span style="font-family:宋體;mso-ascii-font-family:&quot;Times New Roman&quot;;mso-hansi-font-family:&quot;Times New Roman&quot;;">量超標(biāo)；點(diǎn)焊點(diǎn)打磨後，封底焊焊接過(guò)程中通過(guò)觀察焊道顏色來(lái)確定焊接氣體保護(hù)效果，采用混合氣體施焊時(shí)焊道好為金黃色，稍差一些為黃銅色，儘量減少焊縫發(fā)藍(lán)，杜絕焊道發(fā)灰和發(fā)黑，並嚴(yán)格控製層間溫度，控製熔池在紅熱狀態(tài)下停留時(shí)間。一般來(lái)講，隻要保證在</span><span style="font-family:'Times New Roman';"><span lang="EN-US">5~15s</span></span><span style="font-family:宋體;mso-ascii-font-family:&quot;Times New Roman&quot;;mso-hansi-font-family:&quot;Times New Roman&quot;;">時(shí)間內(nèi)熔池由紅轉(zhuǎn)至常規(guī)顏色，就能達(dá)到要求。打底焊的層間溫度</span><span style="font-family:'Times New Roman';"><span lang="EN-US">≤100</span></span><span style="font-family:宋體;mso-ascii-font-family:&quot;Times New Roman&quot;;mso-hansi-font-family:&quot;Times New Roman&quot;;">℃，可用遠(yuǎn)紅外激光測(cè)溫儀測(cè)量。當(dāng)層間溫度＜</span><span style="font-family:'Times New Roman';"><span lang="EN-US">100</span></span><span style="font-family:宋體;mso-ascii-font-family:&quot;Times New Roman&quot;;mso-hansi-font-family:&quot;Times New Roman&quot;;">℃時(shí)，才能進(jìn)行下一層焊接，焊接電流不能超過(guò)打底焊的電流，焊**層必須認(rèn)真清理前一層焊道，除消除雜質(zhì)外，連氧化色也需磨去，焊縫內(nèi)部餘高應(yīng)控製在</span><span style="font-family:'Times New Roman';"><span lang="EN-US">0.5 ~1mm</span></span><span style="font-family:宋體;mso-ascii-font-family:&quot;Times New Roman&quot;;mso-hansi-font-family:&quot;Times New Roman&quot;;">；焊縫收弧時(shí)應(yīng)將弧坑填滿(mǎn)，多層焊的層間接頭應(yīng)相互錯(cuò)開(kāi)，如果焊接作業(yè)時(shí)不慎出現(xiàn)夾鎢時(shí)，應(yīng)停止焊接作業(yè)，用磨光機(jī)消除鎢點(diǎn)，鎢極端部重新磨尖，達(dá)到要求後方可重新進(jìn)行焊接作業(yè)，要求與開(kāi)始焊接作業(yè)相同。</span></span><span lang="EN-US"><br /> <span style="font-family:'Times New Roman';font-size:small;"> 2.9&nbsp; &nbsp; </span></span><span style="font-family:宋體;mso-ascii-font-family:&quot;Times New Roman&quot;;mso-hansi-font-family:&quot;Times New Roman&quot;;"><span style="font-size:small;">焊後清理和焊接檢驗(yàn)</span></span><span lang="EN-US"><br /> <span style="font-family:'Times New Roman';font-size:small;"> </span></span><span style="font-size:small;"><span style="font-family:宋體;mso-ascii-font-family:&quot;Times New Roman&quot;;mso-hansi-font-family:&quot;Times New Roman&quot;;">雙相不鏽鋼的焊後清理也很重要，氧化色必須**，因?yàn)檠趸曼I就是貧鉻層，若不去除將會(huì)導(dǎo)致耐蝕性能下降，去除氧化色可用專(zhuān)用不鏽鋼絲刷趁熱擦刷；也可用酸或酸洗膏清洗。去除焊接飛濺，打磨收起弧點(diǎn)，去除咬邊和粗毛刺?？捎幂^細(xì)的砂輪片或拋光砂輪片研磨，杜絕粗糙打磨痕跡，否則易造成縫隙腐蝕；油汙、著色劑、色筆印、灰塵均有可能成為孔腐蝕和縫隙腐蝕的起始點(diǎn)，可用硝酸</span><span style="font-family:'Times New Roman';"><span lang="EN-US">+</span></span><span style="font-family:宋體;mso-ascii-font-family:&quot;Times New Roman&quot;;mso-hansi-font-family:&quot;Times New Roman&quot;;">氫氟酸清洗，然後清水衝洗乾淨(jìng)；焊工應(yīng)對(duì)焊道表麵進(jìn)行清理，要求外觀良好，寬度以每邊蓋過(guò)坡口邊緣</span><span style="font-family:'Times New Roman';"><span lang="EN-US">2mm</span></span><span style="font-family:宋體;mso-ascii-font-family:&quot;Times New Roman&quot;;mso-hansi-font-family:&quot;Times New Roman&quot;;">為宜，角焊縫的焊腳高度符合設(shè)計(jì)規(guī)定外形平穩(wěn)過(guò)渡，焊縫不允許咬邊、裂紋、未焊透、氣孔、夾雜存在。射線(xiàn)探傷方法按《壓力容器無(wú)損檢測(cè)》</span><span style="font-family:'Times New Roman';"><span lang="EN-US">JB4730-g4</span></span><span style="font-family:宋體;mso-ascii-font-family:&quot;Times New Roman&quot;;mso-hansi-font-family:&quot;Times New Roman&quot;;">執(zhí)行，所有焊道必須進(jìn)行硬度測(cè)定，測(cè)定母材</span><span style="font-family:'Times New Roman';"><span lang="EN-US">-HAZ-</span></span><span style="font-family:宋體;mso-ascii-font-family:&quot;Times New Roman&quot;;mso-hansi-font-family:&quot;Times New Roman&quot;;">焊道</span><span style="font-family:'Times New Roman';"><span lang="EN-US">-HAZ-</span></span><span style="font-family:宋體;mso-ascii-font-family:&quot;Times New Roman&quot;;mso-hansi-font-family:&quot;Times New Roman&quot;;">母材。</span></span><span lang="EN-US"><br /> <span style="font-family:'Times New Roman';font-size:small;"> 3&nbsp; &nbsp; </span></span><span style="font-family:宋體;mso-ascii-font-family:&quot;Times New Roman&quot;;mso-hansi-font-family:&quot;Times New Roman&quot;;"><span style="font-size:small;">結(jié)束語(yǔ)</span></span><span lang="EN-US"><br /> <span style="font-family:'Times New Roman';font-size:small;"> </span></span><span style="font-size:small;"><span style="font-family:宋體;mso-ascii-font-family:&quot;Times New Roman&quot;;mso-hansi-font-family:&quot;Times New Roman&quot;;">采用上述焊接工藝和焊接操作要領(lǐng)，在儀征化纖</span><span style="font-family:'Times New Roman';"><span lang="EN-US">45</span></span><span style="font-family:宋體;mso-ascii-font-family:&quot;Times New Roman&quot;;mso-hansi-font-family:&quot;Times New Roman&quot;;">萬(wàn)噸</span><span style="font-family:'Times New Roman';"><span lang="EN-US">/</span></span><span style="font-family:宋體;mso-ascii-font-family:&quot;Times New Roman&quot;;mso-hansi-font-family:&quot;Times New Roman&quot;;">年</span><span style="font-family:'Times New Roman';"><span lang="EN-US">PTA</span></span><span style="font-family:宋體;mso-ascii-font-family:&quot;Times New Roman&quot;;mso-hansi-font-family:&quot;Times New Roman&quot;;">裝置施工過(guò)程中進(jìn)行雙相不鏽鋼薄壁管現(xiàn)場(chǎng)施焊，取得了焊縫連續(xù)</span><span style="font-family:'Times New Roman';"><span lang="EN-US">5</span></span><span style="font-family:宋體;mso-ascii-font-family:&quot;Times New Roman&quot;;mso-hansi-font-family:&quot;Times New Roman&quot;;">個(gè)月</span><span style="font-family:'Times New Roman';"><span lang="EN-US">RT100%</span></span><span style="font-family:宋體;mso-ascii-font-family:&quot;Times New Roman&quot;;mso-hansi-font-family:&quot;Times New Roman&quot;;">合格，年度雙相不鏽鋼焊接接頭綜合合格率達(dá)到</span><span style="font-family:'Times New Roman';"><span lang="EN-US">99%</span></span><span style="font-family:宋體;mso-ascii-font-family:&quot;Times New Roman&quot;;mso-hansi-font-family:&quot;Times New Roman&quot;;">以上的施焊業(yè)績(jī)。</span></span> </p> <span style="font-family:宋體;font-size:small;"> </span>