①. 由于各國不銹鋼(gang)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. 支管連接件的選擇(ze)主要依據管道等(deng)級中已經確定的法蘭(lan)壓力等(deng)級或公稱(cheng)壓力來選用(yong)支管連接件。

    一(yi)般情況下，當(dang)法蘭的(de)公稱壓力不大(da)于PN2.5（Class 150）時，支管(guan)(guan)(guan)直接(jie)焊(han)接(jie)在主管(guan)(guan)(guan)上；當(dang)公稱壓力不小于PN4.0（Class 300）時，則根據主管(guan)(guan)(guan)、支管(guan)(guan)(guan)公稱直徑的(de)不同按對焊(han)三通(tong)、焊(han)接(jie)支管(guan)(guan)(guan)臺(tai)、承(cheng)插焊(han)或螺(luo)紋連接(jie)三通(tong)、承(cheng)插焊(han)或螺(luo)紋支管(guan)(guan)(guan)臺(tai)的(de)順序選用。

  ③. 支管連接件的管子表號(hao)。

   值得注意(yi)的(de)(de)(de)是(shi)在確定支管(guan)(guan)(guan)(guan)(guan)(guan)(guan)連接(jie)件(jian)(jian)(jian)的(de)(de)(de)管(guan)(guan)(guan)(guan)(guan)(guan)(guan)子(zi)(zi)表(biao)(biao)(biao)號(hao)(hao)(hao)時，應根(gen)據(ju)管(guan)(guan)(guan)(guan)(guan)(guan)(guan)子(zi)(zi)與管(guan)(guan)(guan)(guan)(guan)(guan)(guan)件(jian)(jian)(jian)等(deng)強度(du)的(de)(de)(de)原則以(yi)及管(guan)(guan)(guan)(guan)(guan)(guan)(guan)件(jian)(jian)(jian)與管(guan)(guan)(guan)(guan)(guan)(guan)(guan)子(zi)(zi)連接(jie)方式(shi)而(er)定。例如，當(dang)管(guan)(guan)(guan)(guan)(guan)(guan)(guan)子(zi)(zi)與管(guan)(guan)(guan)(guan)(guan)(guan)(guan)件(jian)(jian)(jian)采用對焊(han)(han)連接(jie)時，管(guan)(guan)(guan)(guan)(guan)(guan)(guan)子(zi)(zi)與不(bu)銹鋼管(guan)(guan)(guan)(guan)(guan)(guan)(guan)件(jian)(jian)(jian)的(de)(de)(de)管(guan)(guan)(guan)(guan)(guan)(guan)(guan)子(zi)(zi)表(biao)(biao)(biao)號(hao)(hao)(hao)應一致；而(er)當(dang)管(guan)(guan)(guan)(guan)(guan)(guan)(guan)子(zi)(zi)與管(guan)(guan)(guan)(guan)(guan)(guan)(guan)件(jian)(jian)(jian)采用承插焊(han)(han)或螺(luo)紋(wen)(wen)連接(jie)時，標(biao)準的(de)(de)(de)承插焊(han)(han)和螺(luo)紋(wen)(wen)管(guan)(guan)(guan)(guan)(guan)(guan)(guan)件(jian)(jian)(jian)的(de)(de)(de)管(guan)(guan)(guan)(guan)(guan)(guan)(guan)子(zi)(zi)表(biao)(biao)(biao)號(hao)(hao)(hao)只有Sch80、Sch160、XXS三擋，最低的(de)(de)(de)管(guan)(guan)(guan)(guan)(guan)(guan)(guan)子(zi)(zi)表(biao)(biao)(biao)號(hao)(hao)(hao)就(jiu)是(shi)Sch80，也(ye)就(jiu)是(shi)說(shuo)只要當(dang)承插焊(han)(han)或螺(luo)紋(wen)(wen)管(guan)(guan)(guan)(guan)(guan)(guan)(guan)件(jian)(jian)(jian)所連接(jie)的(de)(de)(de)管(guan)(guan)(guan)(guan)(guan)(guan)(guan)子(zi)(zi)表(biao)(biao)(biao)號(hao)(hao)(hao)不(bu)大于(yu)Sch80時，承插焊(han)(han)或螺(luo)紋(wen)(wen)管(guan)(guan)(guan)(guan)(guan)(guan)(guan)件(jian)(jian)(jian)的(de)(de)(de)管(guan)(guan)(guan)(guan)(guan)(guan)(guan)子(zi)(zi)表(biao)(biao)(biao)號(hao)(hao)(hao)就(jiu)選(xuan)Sch80，而(er)當(dang)所連接(jie)的(de)(de)(de)管(guan)(guan)(guan)(guan)(guan)(guan)(guan)子(zi)(zi)表(biao)(biao)(biao)號(hao)(hao)(hao)大于(yu)Sch80時，承插焊(han)(han)或螺(luo)紋(wen)(wen)管(guan)(guan)(guan)(guan)(guan)(guan)(guan)件(jian)(jian)(jian)的(de)(de)(de)管(guan)(guan)(guan)(guan)(guan)(guan)(guan)子(zi)(zi)表(biao)(biao)(biao)號(hao)(hao)(hao)就(jiu)選(xuan)Sch160或XXS。

   另外，當對焊三通主(zhu)管(guan)、支管(guan)所(suo)(suo)連接(jie)的(de)管(guan)子的(de)管(guan)子表(biao)號不(bu)同時(shi)，應(ying)注意三通主(zhu)管(guan)、支管(guan)端部的(de)管(guan)子表(biao)號應(ying)分別(bie)與其所(suo)(suo)連接(jie)的(de)管(guan)子的(de)管(guan)子表(biao)號相同，這(zhe)樣就非常方(fang)便管(guan)道施工，管(guan)件不(bu)必現場再(zai)打坡(po)口(kou)。

   值得注(zhu)意的是選(xuan)用支管直接焊接在主管上這一(yi)種連(lian)接形式(shi)，要核(he)算(suan)管子(zi)是否需要補(bu)強。支管補(bu)強的方法在ASME B31.3、SH／T 3059《石油化工(gong)管道(dao)設計器材(cai)選(xuan)用規(gui)(gui)范》、GB50316《工(gong)業金屬管道(dao)設計規(gui)(gui)范》、GB／T 20801《壓力(li)管道(dao)規(gui)(gui)范工(gong)業管道(dao)》等(deng)標準規(gui)(gui)范中均有(you)詳(xiang)細的介紹。