摘要：<p style="margin:0pt;"> <span style="font-family:宋體;font-size:10.5pt;mso-spacerun:&quot;yes&quot;;mso-ascii-font-family:Calibri;mso-hansi-font-family:Calibri;mso-bidi-font-family:&quot;Times New Roman&quot;;mso-font-kerning:1.0000pt;"><span style="font-family:宋體;">西安</span></span><span style="font-family:宋體;font-size:10.5pt;mso-spacerun:&quot;yes&quot;;mso-ascii-font-family:Calibri;mso-hansi-font-family:Calibri;mso-bidi-font-family:&quot;Times New Roman&quot;;mso-font-kerning:1.0000pt;"><span style="font-family:宋體;">不鏽鋼換熱管與管板的焊接</span></span><span style="font-family:宋體;font-size:10.5pt;mso-spacerun:&quot;yes&quot;;mso-ascii-font-family:Calibri;mso-hansi-font-family:Calibri;mso-bidi-font-family:&quot;Times New Roman&quot;;mso-font-kerning:1.0000pt;"><span style="font-family:宋體;">工藝</span></span> </p> <p style="margin:0pt;"> <span style="font-family:宋體;font-size:10.5pt;mso-spacerun:&quot;yes&quot;;mso-ascii-font-family:Calibri;mso-hansi-font-family:Calibri;mso-bidi-font-family:&quot;Times New Roman&quot;;mso-font-kerning:1.0000pt;"><span style="font-family:宋體;">西安</span></span><span style="font-family:宋體;font-size:10.5pt;mso-spacerun:&quot;yes&quot;;mso-ascii-font-family:Calibri;mso-hansi-font-family:Calibri;mso-bidi-font-family:&quot;Times New Roman&quot;;mso-font-kerning:1.0000pt;"><span style="font-family:宋體;">不鏽鋼換熱管與管板的焊接</span></span><span style="font-family:宋體;font-size:10.5pt;mso-spacerun:&quot;yes&quot;;mso-ascii-font-family:Calibri;mso-hansi-font-family:Calibri;mso-bidi-font-family:&quot;Times New Roman&quot;;mso-font-kerning:1.0000pt;"><span style="font-family:宋體;">工藝</span></span><span style="font-family:宋體;font-size:10.5pt;mso-spacerun:&quot;yes&quot;;mso-ascii-font-family:Calibri;mso-hansi-font-family:Calibri;mso-bidi-font-family:&quot;Times New Roman&quot;;mso-font-kerning:1.0000pt;"><span style="font-family:宋體;">結構可分為正麵、背麵形成焊縫兩類(lèi)。選擇哪種結構，需要看具體的使用條件，即是否存在間隙腐蝕（不鏽鋼換熱管與管板管孔的間隙），以及不鏽鋼換熱管和管板的材料的加工機械性能，焊接冶金性能，並結合加工裝備和技術(shù)能力綜合考慮。</span></span> </p> <p style="margin:0pt;"> <span style="font-family:宋體;font-size:10.5pt;mso-spacerun:&quot;yes&quot;;mso-ascii-font-family:Calibri;mso-hansi-font-family:Calibri;mso-bidi-font-family:&quot;Times New Roman&quot;;mso-font-kerning:1.0000pt;"><span style="font-family:Calibri;">&nbsp;</span><span style="font-family:宋體;">一 管板正麵形成焊縫</span></span> </p> <p style="margin:0pt;"> <span style="font-family:宋體;font-size:10.5pt;mso-spacerun:&quot;yes&quot;;mso-ascii-font-family:Calibri;mso-hansi-font-family:Calibri;mso-bidi-font-family:&quot;Times New Roman&quot;;mso-font-kerning:1.0000pt;"><span style="font-family:宋體;">與背麵焊相比，正麵焊加工和焊接引對簡(jiǎn)便，但無(wú)論是脹還是不脹，正麵焊焊後都有焊縫根部的應力集中問(wèn)題，並且換熱管與管板管孔間隙無(wú)法完全消除，存在間隙腐蝕的條件。</span></span> </p> <p style="margin:0pt;"> <span style="font-family:宋體;font-size:10.5pt;mso-spacerun:&quot;yes&quot;;mso-ascii-font-family:Calibri;mso-hansi-font-family:Calibri;mso-bidi-font-family:&quot;Times New Roman&quot;;mso-font-kerning:1.0000pt;"><span style="font-family:宋體;">如上麵兩個(gè)截圖所示，</span><span style="font-family:宋體;">“正麵形成焊縫”又可以分為：</span></span> </p> <p style="margin:0pt;"> <span style="font-family:宋體;font-size:10.5pt;mso-spacerun:&quot;yes&quot;;mso-ascii-font-family:Calibri;mso-hansi-font-family:Calibri;mso-bidi-font-family:&quot;Times New Roman&quot;;mso-font-kerning:1.0000pt;"><span style="font-family:Calibri;">1. </span><span style="font-family:宋體;">正麵角焊縫式</span></span> </p> <p style="margin:0pt;"> <span style="font-family:宋體;font-size:10.5pt;mso-spacerun:&quot;yes&quot;;mso-ascii-font-family:Calibri;mso-hansi-font-family:Calibri;mso-bidi-font-family:&quot;Times New Roman&quot;;mso-font-kerning:1.0000pt;"><span style="font-family:宋體;">換熱管管端伸出管板，可形成各種焊腳高度尺寸的焊縫。這個(gè)焊腳尺寸需要強度校核的，這種型式便於計算不過(guò)時(shí)調整。</span></span> </p> <p style="margin:0pt;"> <span style="font-family:宋體;font-size:10.5pt;mso-spacerun:&quot;yes&quot;;mso-ascii-font-family:Calibri;mso-hansi-font-family:Calibri;mso-bidi-font-family:&quot;Times New Roman&quot;;mso-font-kerning:1.0000pt;"><span style="font-family:宋體;">這種結構手工焊和自動(dòng)焊均可。多道焊時(shí)，在完成打底焊後可進(jìn)行目測檢查和</span><span style="font-family:Calibri;">PT</span><span style="font-family:宋體;">，以控製根部焊縫質(zhì)量。</span></span> </p> <p style="margin:0pt;"> <span style="font-family:宋體;font-size:10.5pt;mso-spacerun:&quot;yes&quot;;mso-ascii-font-family:Calibri;mso-hansi-font-family:Calibri;mso-bidi-font-family:&quot;Times New Roman&quot;;mso-font-kerning:1.0000pt;"><span style="font-family:宋體;">另外，這種結構在製造時(shí)可預先將管端伸出管板足夠長(cháng)，待焊接完成後，可對整個(gè)管板的管口端部進(jìn)行機械加工，使所有管口端麵在同一水平麵上。對於生產(chǎn)工藝上要求管內壁形成均勻液膜立式安裝的換熱器、冷凝器，可采用這種結構。</span></span> </p> <p style="margin:0pt;"> <span style="font-family:宋體;font-size:10.5pt;mso-spacerun:&quot;yes&quot;;mso-ascii-font-family:Calibri;mso-hansi-font-family:Calibri;mso-bidi-font-family:&quot;Times New Roman&quot;;mso-font-kerning:1.0000pt;"><span style="font-family:宋體;">不過(guò)，這種角焊縫的缺點(diǎn)在於，由於管端突出，比起入口圓滑的換熱管與管板平齊、換熱管端下沉的結構，它會(huì )產(chǎn)生較大的入口斷麵收縮率（參考文獻如此，個(gè)人不太理解），在管口可能存在介質(zhì)衝蝕。</span></span> </p>