①. 由于各國不銹鋼管件標準化程度不同，分支管連接方式及管件的選擇也不盡相同。一般情況下，支管連接多采用成型支管連接件、焊接的引出口連接件以及支管直接焊接在主管上等連接形式。

  ②. 支(zhi)管(guan)連接(jie)件(jian)的(de)(de)選擇主要依據管(guan)道等(deng)級中已經確定的(de)(de)法蘭(lan)壓力(li)等(deng)級或公稱壓力(li)來選用支(zhi)管(guan)連接(jie)件(jian)。

    一(yi)般情(qing)況下，當法蘭的公稱壓(ya)力不(bu)大于PN2.5（Class 150）時，支管(guan)(guan)直接(jie)焊接(jie)在主管(guan)(guan)上；當公稱壓(ya)力不(bu)小于PN4.0（Class 300）時，則根據主管(guan)(guan)、支管(guan)(guan)公稱直徑的不(bu)同(tong)按對(dui)焊三通(tong)、焊接(jie)支管(guan)(guan)臺、承(cheng)(cheng)插焊或(huo)螺紋連接(jie)三通(tong)、承(cheng)(cheng)插焊或(huo)螺紋支管(guan)(guan)臺的順序選用(yong)。

  ③. 支管(guan)(guan)連接件的管(guan)(guan)子表號。

   值得(de)注意的(de)(de)(de)(de)是(shi)在確(que)定(ding)支(zhi)管(guan)(guan)(guan)(guan)(guan)(guan)(guan)(guan)(guan)(guan)連(lian)接(jie)件的(de)(de)(de)(de)管(guan)(guan)(guan)(guan)(guan)(guan)(guan)(guan)(guan)(guan)子(zi)(zi)表(biao)(biao)號(hao)(hao)時，應根據管(guan)(guan)(guan)(guan)(guan)(guan)(guan)(guan)(guan)(guan)子(zi)(zi)與(yu)(yu)管(guan)(guan)(guan)(guan)(guan)(guan)(guan)(guan)(guan)(guan)件等(deng)強度的(de)(de)(de)(de)原則以及管(guan)(guan)(guan)(guan)(guan)(guan)(guan)(guan)(guan)(guan)件與(yu)(yu)管(guan)(guan)(guan)(guan)(guan)(guan)(guan)(guan)(guan)(guan)子(zi)(zi)連(lian)接(jie)方式(shi)而(er)定(ding)。例如，當管(guan)(guan)(guan)(guan)(guan)(guan)(guan)(guan)(guan)(guan)子(zi)(zi)與(yu)(yu)管(guan)(guan)(guan)(guan)(guan)(guan)(guan)(guan)(guan)(guan)件采用對焊連(lian)接(jie)時，管(guan)(guan)(guan)(guan)(guan)(guan)(guan)(guan)(guan)(guan)子(zi)(zi)與(yu)(yu)不銹(xiu)鋼管(guan)(guan)(guan)(guan)(guan)(guan)(guan)(guan)(guan)(guan)件的(de)(de)(de)(de)管(guan)(guan)(guan)(guan)(guan)(guan)(guan)(guan)(guan)(guan)子(zi)(zi)表(biao)(biao)號(hao)(hao)應一致(zhi)；而(er)當管(guan)(guan)(guan)(guan)(guan)(guan)(guan)(guan)(guan)(guan)子(zi)(zi)與(yu)(yu)管(guan)(guan)(guan)(guan)(guan)(guan)(guan)(guan)(guan)(guan)件采用承(cheng)(cheng)插(cha)(cha)(cha)焊或(huo)螺(luo)紋(wen)連(lian)接(jie)時，標準的(de)(de)(de)(de)承(cheng)(cheng)插(cha)(cha)(cha)焊和螺(luo)紋(wen)管(guan)(guan)(guan)(guan)(guan)(guan)(guan)(guan)(guan)(guan)件的(de)(de)(de)(de)管(guan)(guan)(guan)(guan)(guan)(guan)(guan)(guan)(guan)(guan)子(zi)(zi)表(biao)(biao)號(hao)(hao)只有Sch80、Sch160、XXS三擋(dang)，最低的(de)(de)(de)(de)管(guan)(guan)(guan)(guan)(guan)(guan)(guan)(guan)(guan)(guan)子(zi)(zi)表(biao)(biao)號(hao)(hao)就(jiu)是(shi)Sch80，也(ye)就(jiu)是(shi)說只要當承(cheng)(cheng)插(cha)(cha)(cha)焊或(huo)螺(luo)紋(wen)管(guan)(guan)(guan)(guan)(guan)(guan)(guan)(guan)(guan)(guan)件所(suo)連(lian)接(jie)的(de)(de)(de)(de)管(guan)(guan)(guan)(guan)(guan)(guan)(guan)(guan)(guan)(guan)子(zi)(zi)表(biao)(biao)號(hao)(hao)不大于Sch80時，承(cheng)(cheng)插(cha)(cha)(cha)焊或(huo)螺(luo)紋(wen)管(guan)(guan)(guan)(guan)(guan)(guan)(guan)(guan)(guan)(guan)件的(de)(de)(de)(de)管(guan)(guan)(guan)(guan)(guan)(guan)(guan)(guan)(guan)(guan)子(zi)(zi)表(biao)(biao)號(hao)(hao)就(jiu)選Sch80，而(er)當所(suo)連(lian)接(jie)的(de)(de)(de)(de)管(guan)(guan)(guan)(guan)(guan)(guan)(guan)(guan)(guan)(guan)子(zi)(zi)表(biao)(biao)號(hao)(hao)大于Sch80時，承(cheng)(cheng)插(cha)(cha)(cha)焊或(huo)螺(luo)紋(wen)管(guan)(guan)(guan)(guan)(guan)(guan)(guan)(guan)(guan)(guan)件的(de)(de)(de)(de)管(guan)(guan)(guan)(guan)(guan)(guan)(guan)(guan)(guan)(guan)子(zi)(zi)表(biao)(biao)號(hao)(hao)就(jiu)選Sch160或(huo)XXS。

   另外，當對(dui)焊(han)三通(tong)主管(guan)(guan)(guan)、支(zhi)管(guan)(guan)(guan)所連接的(de)管(guan)(guan)(guan)子(zi)的(de)管(guan)(guan)(guan)子(zi)表(biao)號(hao)(hao)(hao)不同(tong)時(shi)，應(ying)注(zhu)意三通(tong)主管(guan)(guan)(guan)、支(zhi)管(guan)(guan)(guan)端部的(de)管(guan)(guan)(guan)子(zi)表(biao)號(hao)(hao)(hao)應(ying)分別與其所連接的(de)管(guan)(guan)(guan)子(zi)的(de)管(guan)(guan)(guan)子(zi)表(biao)號(hao)(hao)(hao)相(xiang)同(tong)，這樣就(jiu)非常方便(bian)管(guan)(guan)(guan)道(dao)施工，管(guan)(guan)(guan)件不必(bi)現場再(zai)打坡口。

   值得注意(yi)的是(shi)選(xuan)用(yong)支(zhi)管(guan)(guan)直接焊接在(zai)主管(guan)(guan)上這一種(zhong)連接形式(shi)，要核(he)算管(guan)(guan)子是(shi)否需(xu)要補(bu)強(qiang)。支(zhi)管(guan)(guan)補(bu)強(qiang)的方法在(zai)ASME B31.3、SH／T 3059《石油化工(gong)管(guan)(guan)道(dao)設計器材選(xuan)用(yong)規范(fan)》、GB50316《工(gong)業(ye)金屬管(guan)(guan)道(dao)設計規范(fan)》、GB／T 20801《壓力(li)管(guan)(guan)道(dao)規范(fan)工(gong)業(ye)管(guan)(guan)道(dao)》等標準規范(fan)中均有詳(xiang)細的介紹。