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)管連接件(jian)的選擇(ze)主(zhu)要依據(ju)管道等級中已經(jing)確(que)定的法蘭(lan)壓力(li)等級或公稱壓力(li)來選用(yong)支(zhi)管連接件(jian)。

    一般情況下，當法(fa)蘭(lan)的(de)公(gong)(gong)稱(cheng)壓力不(bu)大于(yu)PN2.5（Class 150）時，支管(guan)直接(jie)焊(han)(han)(han)(han)接(jie)在(zai)主管(guan)上；當公(gong)(gong)稱(cheng)壓力不(bu)小于(yu)PN4.0（Class 300）時，則根據主管(guan)、支管(guan)公(gong)(gong)稱(cheng)直徑的(de)不(bu)同按對焊(han)(han)(han)(han)三通(tong)、焊(han)(han)(han)(han)接(jie)支管(guan)臺、承插焊(han)(han)(han)(han)或(huo)螺紋連接(jie)三通(tong)、承插焊(han)(han)(han)(han)或(huo)螺紋支管(guan)臺的(de)順序選用。

  ③. 支管(guan)連接件的管(guan)子表號。

   值得注意的(de)(de)(de)(de)是(shi)在確定支管(guan)(guan)連(lian)(lian)接件(jian)(jian)的(de)(de)(de)(de)管(guan)(guan)子(zi)(zi)(zi)(zi)(zi)(zi)表(biao)(biao)(biao)號(hao)時(shi)，應(ying)(ying)根據管(guan)(guan)子(zi)(zi)(zi)(zi)(zi)(zi)與(yu)(yu)管(guan)(guan)件(jian)(jian)等強(qiang)度的(de)(de)(de)(de)原則(ze)以及管(guan)(guan)件(jian)(jian)與(yu)(yu)管(guan)(guan)子(zi)(zi)(zi)(zi)(zi)(zi)連(lian)(lian)接方式而定。例如，當管(guan)(guan)子(zi)(zi)(zi)(zi)(zi)(zi)與(yu)(yu)管(guan)(guan)件(jian)(jian)采(cai)用(yong)對焊(han)連(lian)(lian)接時(shi)，管(guan)(guan)子(zi)(zi)(zi)(zi)(zi)(zi)與(yu)(yu)不(bu)銹鋼管(guan)(guan)件(jian)(jian)的(de)(de)(de)(de)管(guan)(guan)子(zi)(zi)(zi)(zi)(zi)(zi)表(biao)(biao)(biao)號(hao)應(ying)(ying)一致；而當管(guan)(guan)子(zi)(zi)(zi)(zi)(zi)(zi)與(yu)(yu)管(guan)(guan)件(jian)(jian)采(cai)用(yong)承(cheng)插焊(han)或(huo)(huo)螺紋(wen)連(lian)(lian)接時(shi)，標準的(de)(de)(de)(de)承(cheng)插焊(han)和螺紋(wen)管(guan)(guan)件(jian)(jian)的(de)(de)(de)(de)管(guan)(guan)子(zi)(zi)(zi)(zi)(zi)(zi)表(biao)(biao)(biao)號(hao)只(zhi)(zhi)有Sch80、Sch160、XXS三擋，最低的(de)(de)(de)(de)管(guan)(guan)子(zi)(zi)(zi)(zi)(zi)(zi)表(biao)(biao)(biao)號(hao)就是(shi)Sch80，也就是(shi)說(shuo)只(zhi)(zhi)要當承(cheng)插焊(han)或(huo)(huo)螺紋(wen)管(guan)(guan)件(jian)(jian)所(suo)連(lian)(lian)接的(de)(de)(de)(de)管(guan)(guan)子(zi)(zi)(zi)(zi)(zi)(zi)表(biao)(biao)(biao)號(hao)不(bu)大于(yu)Sch80時(shi)，承(cheng)插焊(han)或(huo)(huo)螺紋(wen)管(guan)(guan)件(jian)(jian)的(de)(de)(de)(de)管(guan)(guan)子(zi)(zi)(zi)(zi)(zi)(zi)表(biao)(biao)(biao)號(hao)就選Sch80，而當所(suo)連(lian)(lian)接的(de)(de)(de)(de)管(guan)(guan)子(zi)(zi)(zi)(zi)(zi)(zi)表(biao)(biao)(biao)號(hao)大于(yu)Sch80時(shi)，承(cheng)插焊(han)或(huo)(huo)螺紋(wen)管(guan)(guan)件(jian)(jian)的(de)(de)(de)(de)管(guan)(guan)子(zi)(zi)(zi)(zi)(zi)(zi)表(biao)(biao)(biao)號(hao)就選Sch160或(huo)(huo)XXS。

   另外，當(dang)對(dui)焊三通主管(guan)(guan)(guan)、支(zhi)管(guan)(guan)(guan)所連(lian)接的(de)(de)管(guan)(guan)(guan)子(zi)的(de)(de)管(guan)(guan)(guan)子(zi)表號(hao)不同(tong)時，應注(zhu)意三通主管(guan)(guan)(guan)、支(zhi)管(guan)(guan)(guan)端部的(de)(de)管(guan)(guan)(guan)子(zi)表號(hao)應分別與其所連(lian)接的(de)(de)管(guan)(guan)(guan)子(zi)的(de)(de)管(guan)(guan)(guan)子(zi)表號(hao)相同(tong)，這樣就(jiu)非常(chang)方便管(guan)(guan)(guan)道施工，管(guan)(guan)(guan)件不必現場再(zai)打(da)坡口。

   值得注意的(de)(de)是選用支管(guan)(guan)(guan)(guan)(guan)直接焊接在主管(guan)(guan)(guan)(guan)(guan)上這一種連接形式，要核算管(guan)(guan)(guan)(guan)(guan)子是否需要補(bu)強。支管(guan)(guan)(guan)(guan)(guan)補(bu)強的(de)(de)方法在ASME B31.3、SH／T 3059《石油(you)化工管(guan)(guan)(guan)(guan)(guan)道(dao)(dao)設計器材(cai)選用規(gui)(gui)范》、GB50316《工業金(jin)屬管(guan)(guan)(guan)(guan)(guan)道(dao)(dao)設計規(gui)(gui)范》、GB／T 20801《壓力管(guan)(guan)(guan)(guan)(guan)道(dao)(dao)規(gui)(gui)范工業管(guan)(guan)(guan)(guan)(guan)道(dao)(dao)》等標準(zhun)規(gui)(gui)范中均有詳細(xi)的(de)(de)介紹。