①. 由于各國不銹鋼管(guan)件(jian)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(jie)件(jian)的(de)選(xuan)擇主要(yao)依據(ju)管道(dao)等級中已經確定(ding)的(de)法蘭(lan)壓(ya)(ya)力(li)等級或公(gong)稱壓(ya)(ya)力(li)來(lai)選(xuan)用支管連接(jie)件(jian)。

    一(yi)般情(qing)況下，當(dang)法(fa)蘭的(de)(de)(de)公稱(cheng)壓力(li)(li)不(bu)(bu)大于PN2.5（Class 150）時，支(zhi)(zhi)管(guan)直接(jie)(jie)焊(han)接(jie)(jie)在主管(guan)上；當(dang)公稱(cheng)壓力(li)(li)不(bu)(bu)小(xiao)于PN4.0（Class 300）時，則根據主管(guan)、支(zhi)(zhi)管(guan)公稱(cheng)直徑的(de)(de)(de)不(bu)(bu)同按對焊(han)三(san)通、焊(han)接(jie)(jie)支(zhi)(zhi)管(guan)臺、承(cheng)插(cha)焊(han)或螺紋(wen)連接(jie)(jie)三(san)通、承(cheng)插(cha)焊(han)或螺紋(wen)支(zhi)(zhi)管(guan)臺的(de)(de)(de)順序選(xuan)用。

  ③. 支管連接件的(de)管子表號。

   值得注意的(de)(de)(de)是(shi)在確定(ding)支管(guan)(guan)(guan)(guan)(guan)連(lian)接(jie)件(jian)(jian)的(de)(de)(de)管(guan)(guan)(guan)(guan)(guan)子(zi)(zi)(zi)表號(hao)時(shi)，應根據管(guan)(guan)(guan)(guan)(guan)子(zi)(zi)(zi)與(yu)管(guan)(guan)(guan)(guan)(guan)件(jian)(jian)等強度的(de)(de)(de)原則以及管(guan)(guan)(guan)(guan)(guan)件(jian)(jian)與(yu)管(guan)(guan)(guan)(guan)(guan)子(zi)(zi)(zi)連(lian)接(jie)方式而(er)定(ding)。例如，當管(guan)(guan)(guan)(guan)(guan)子(zi)(zi)(zi)與(yu)管(guan)(guan)(guan)(guan)(guan)件(jian)(jian)采用對(dui)焊(han)連(lian)接(jie)時(shi)，管(guan)(guan)(guan)(guan)(guan)子(zi)(zi)(zi)與(yu)不銹鋼(gang)管(guan)(guan)(guan)(guan)(guan)件(jian)(jian)的(de)(de)(de)管(guan)(guan)(guan)(guan)(guan)子(zi)(zi)(zi)表號(hao)應一致；而(er)當管(guan)(guan)(guan)(guan)(guan)子(zi)(zi)(zi)與(yu)管(guan)(guan)(guan)(guan)(guan)件(jian)(jian)采用承插(cha)焊(han)或(huo)螺紋連(lian)接(jie)時(shi)，標準(zhun)的(de)(de)(de)承插(cha)焊(han)和(he)螺紋管(guan)(guan)(guan)(guan)(guan)件(jian)(jian)的(de)(de)(de)管(guan)(guan)(guan)(guan)(guan)子(zi)(zi)(zi)表號(hao)只有(you)Sch80、Sch160、XXS三擋，最(zui)低的(de)(de)(de)管(guan)(guan)(guan)(guan)(guan)子(zi)(zi)(zi)表號(hao)就是(shi)Sch80，也就是(shi)說只要當承插(cha)焊(han)或(huo)螺紋管(guan)(guan)(guan)(guan)(guan)件(jian)(jian)所連(lian)接(jie)的(de)(de)(de)管(guan)(guan)(guan)(guan)(guan)子(zi)(zi)(zi)表號(hao)不大于Sch80時(shi)，承插(cha)焊(han)或(huo)螺紋管(guan)(guan)(guan)(guan)(guan)件(jian)(jian)的(de)(de)(de)管(guan)(guan)(guan)(guan)(guan)子(zi)(zi)(zi)表號(hao)就選(xuan)Sch80，而(er)當所連(lian)接(jie)的(de)(de)(de)管(guan)(guan)(guan)(guan)(guan)子(zi)(zi)(zi)表號(hao)大于Sch80時(shi)，承插(cha)焊(han)或(huo)螺紋管(guan)(guan)(guan)(guan)(guan)件(jian)(jian)的(de)(de)(de)管(guan)(guan)(guan)(guan)(guan)子(zi)(zi)(zi)表號(hao)就選(xuan)Sch160或(huo)XXS。

   另外，當對焊(han)三通主管(guan)(guan)(guan)、支(zhi)管(guan)(guan)(guan)所連(lian)接的管(guan)(guan)(guan)子的管(guan)(guan)(guan)子表(biao)號(hao)不同時，應(ying)注意(yi)三通主管(guan)(guan)(guan)、支(zhi)管(guan)(guan)(guan)端部(bu)的管(guan)(guan)(guan)子表(biao)號(hao)應(ying)分別與其(qi)所連(lian)接的管(guan)(guan)(guan)子的管(guan)(guan)(guan)子表(biao)號(hao)相同，這(zhe)樣就非常方便管(guan)(guan)(guan)道施工，管(guan)(guan)(guan)件不必現場再打坡口。

   值得注意(yi)的是(shi)選用(yong)支管(guan)直接(jie)焊接(jie)在主管(guan)上(shang)這一(yi)種連(lian)接(jie)形式，要核算管(guan)子是(shi)否需要補強。支管(guan)補強的方法在ASME B31.3、SH／T 3059《石油化工(gong)管(guan)道(dao)設(she)計器材選用(yong)規范》、GB50316《工(gong)業金屬(shu)管(guan)道(dao)設(she)計規范》、GB／T 20801《壓力管(guan)道(dao)規范工(gong)業管(guan)道(dao)》等標準規范中(zhong)均有詳細的介紹。