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. 支管(guan)連接件的(de)選擇主要依據(ju)管(guan)道等級中已經確定的(de)法蘭壓力等級或公稱壓力來選用(yong)支管(guan)連接件。

    一般情況下，當法蘭的公(gong)稱(cheng)壓力(li)不(bu)大于PN2.5（Class 150）時，支(zhi)管(guan)(guan)直接(jie)焊(han)(han)接(jie)在主(zhu)管(guan)(guan)上；當公(gong)稱(cheng)壓力(li)不(bu)小于PN4.0（Class 300）時，則根據主(zhu)管(guan)(guan)、支(zhi)管(guan)(guan)公(gong)稱(cheng)直徑的不(bu)同按對(dui)焊(han)(han)三(san)通(tong)、焊(han)(han)接(jie)支(zhi)管(guan)(guan)臺、承插焊(han)(han)或螺紋連(lian)接(jie)三(san)通(tong)、承插焊(han)(han)或螺紋支(zhi)管(guan)(guan)臺的順(shun)序(xu)選(xuan)用。

  ③. 支管連接件的管子表號。

   值得注意的(de)(de)是(shi)在確定支(zhi)管(guan)(guan)(guan)(guan)(guan)(guan)連接(jie)件(jian)(jian)的(de)(de)管(guan)(guan)(guan)(guan)(guan)(guan)子(zi)(zi)表(biao)(biao)(biao)號(hao)時(shi)，應根據管(guan)(guan)(guan)(guan)(guan)(guan)子(zi)(zi)與管(guan)(guan)(guan)(guan)(guan)(guan)件(jian)(jian)等(deng)強度(du)的(de)(de)原則以(yi)及管(guan)(guan)(guan)(guan)(guan)(guan)件(jian)(jian)與管(guan)(guan)(guan)(guan)(guan)(guan)子(zi)(zi)連接(jie)方(fang)式而定。例(li)如，當(dang)管(guan)(guan)(guan)(guan)(guan)(guan)子(zi)(zi)與管(guan)(guan)(guan)(guan)(guan)(guan)件(jian)(jian)采用(yong)對(dui)焊(han)(han)連接(jie)時(shi)，管(guan)(guan)(guan)(guan)(guan)(guan)子(zi)(zi)與不(bu)銹鋼管(guan)(guan)(guan)(guan)(guan)(guan)件(jian)(jian)的(de)(de)管(guan)(guan)(guan)(guan)(guan)(guan)子(zi)(zi)表(biao)(biao)(biao)號(hao)應一致；而當(dang)管(guan)(guan)(guan)(guan)(guan)(guan)子(zi)(zi)與管(guan)(guan)(guan)(guan)(guan)(guan)件(jian)(jian)采用(yong)承插(cha)焊(han)(han)或(huo)(huo)螺(luo)紋(wen)(wen)(wen)連接(jie)時(shi)，標準的(de)(de)承插(cha)焊(han)(han)和螺(luo)紋(wen)(wen)(wen)管(guan)(guan)(guan)(guan)(guan)(guan)件(jian)(jian)的(de)(de)管(guan)(guan)(guan)(guan)(guan)(guan)子(zi)(zi)表(biao)(biao)(biao)號(hao)只有Sch80、Sch160、XXS三擋，最(zui)低的(de)(de)管(guan)(guan)(guan)(guan)(guan)(guan)子(zi)(zi)表(biao)(biao)(biao)號(hao)就是(shi)Sch80，也就是(shi)說(shuo)只要(yao)當(dang)承插(cha)焊(han)(han)或(huo)(huo)螺(luo)紋(wen)(wen)(wen)管(guan)(guan)(guan)(guan)(guan)(guan)件(jian)(jian)所(suo)連接(jie)的(de)(de)管(guan)(guan)(guan)(guan)(guan)(guan)子(zi)(zi)表(biao)(biao)(biao)號(hao)不(bu)大于Sch80時(shi)，承插(cha)焊(han)(han)或(huo)(huo)螺(luo)紋(wen)(wen)(wen)管(guan)(guan)(guan)(guan)(guan)(guan)件(jian)(jian)的(de)(de)管(guan)(guan)(guan)(guan)(guan)(guan)子(zi)(zi)表(biao)(biao)(biao)號(hao)就選Sch80，而當(dang)所(suo)連接(jie)的(de)(de)管(guan)(guan)(guan)(guan)(guan)(guan)子(zi)(zi)表(biao)(biao)(biao)號(hao)大于Sch80時(shi)，承插(cha)焊(han)(han)或(huo)(huo)螺(luo)紋(wen)(wen)(wen)管(guan)(guan)(guan)(guan)(guan)(guan)件(jian)(jian)的(de)(de)管(guan)(guan)(guan)(guan)(guan)(guan)子(zi)(zi)表(biao)(biao)(biao)號(hao)就選Sch160或(huo)(huo)XXS。

   另外(wai)，當(dang)對焊(han)三通(tong)主管(guan)(guan)、支管(guan)(guan)所連(lian)接的管(guan)(guan)子的管(guan)(guan)子表(biao)號不同時，應注意三通(tong)主管(guan)(guan)、支管(guan)(guan)端部的管(guan)(guan)子表(biao)號應分(fen)別與其所連(lian)接的管(guan)(guan)子的管(guan)(guan)子表(biao)號相同，這樣就非常方便管(guan)(guan)道施工(gong)，管(guan)(guan)件不必現場再打坡口。

   值得注意的是選(xuan)用(yong)支管(guan)(guan)(guan)直接焊接在主管(guan)(guan)(guan)上(shang)這(zhe)一種連接形式，要(yao)核算(suan)管(guan)(guan)(guan)子是否需(xu)要(yao)補強。支管(guan)(guan)(guan)補強的方法在ASME B31.3、SH／T 3059《石油化工管(guan)(guan)(guan)道(dao)設計器材選(xuan)用(yong)規范》、GB50316《工業金(jin)屬(shu)管(guan)(guan)(guan)道(dao)設計規范》、GB／T 20801《壓力管(guan)(guan)(guan)道(dao)規范工業管(guan)(guan)(guan)道(dao)》等(deng)標(biao)準規范中(zhong)均(jun)有詳細的介紹。