1. 短(duan)(duan)節(jie)是長(chang)度小于(yu)12in（0.3m）、兩端(duan)(duan)或(huo)一端(duan)(duan)有(you)(you)螺(luo)紋(wen)(wen)(wen)并(bing)便于(yu)進行(xing)焊(han)接(jie)或(huo)機械(xie)連接(jie)的(de)(de)(de)一段(duan)管(guan)(guan)子。當長(chang)度在(zai)12in（0.3m）以(yi)上(shang)時，則稱為(wei)短(duan)(duan)管(guan)(guan)。普通類(lei)型(xing)(xing)的(de)(de)(de)短(duan)(duan)節(jie)是全外(wai)牙型(xing)(xing)，螺(luo)紋(wen)(wen)(wen)接(jie)口的(de)(de)(de)長(chang)度大(da)約(yue)為(wei)標準管(guan)(guan)螺(luo)紋(wen)(wen)(wen)的(de)(de)(de)2倍(bei)，且沒有(you)(you)肩(jian)(jian)(jian)部。任何長(chang)度的(de)(de)(de)帶(dai)肩(jian)(jian)(jian)螺(luo)紋(wen)(wen)(wen)管(guan)(guan)接(jie)頭的(de)(de)(de)兩個(ge)管(guan)(guan)螺(luo)紋(wen)(wen)(wen)間(jian)有(you)(you)肩(jian)(jian)(jian)部；短(duan)(duan)管(guan)(guan)螺(luo)紋(wen)(wen)(wen)管(guan)(guan)接(jie)頭是比全外(wai)牙型(xing)(xing)螺(luo)紋(wen)(wen)(wen)管(guan)(guan)接(jie)頭稍長(chang)的(de)(de)(de)帶(dai)肩(jian)(jian)(jian)螺(luo)紋(wen)(wen)(wen)管(guan)(guan)接(jie)頭，且對于(yu)不同管(guan)(guan)徑的(de)(de)(de)管(guan)(guan)子的(de)(de)(de)特定長(chang)度均要(yao)符合制造(zao)商標準。短(duan)(duan)節(jie)外(wai)形見圖16.29。

   2. 變(bian)徑(jing)短(duan)接(jie)管(guan)(guan)(guan)（圖16.30）也(ye)稱異(yi)形短(duan)節(jie)、漸(jian)縮管(guan)(guan)(guan)，與(yu)大小(xiao)頭（異(yi)徑(jing)管(guan)(guan)(guan)）相同(tong)，用(yong)以減(jian)小(xiao)管(guan)(guan)(guan)線(xian)口徑(jing)。變(bian)徑(jing)短(duan)接(jie)管(guan)(guan)(guan)可設(she)計為螺紋連接(jie)或(huo)者承插焊(han)連接(jie)。變(bian)徑(jing)短(duan)接(jie)管(guan)(guan)(guan)和異(yi)徑(jing)管(guan)(guan)(guan)一樣有同(tong)心(xin)和偏心(xin)之(zhi)分。變(bian)徑(jing)短(duan)接(jie)管(guan)(guan)(guan)大端(duan)及小(xiao)端(duan)分別有平端(duan)、坡口端(duan)、錐管(guan)(guan)(guan)外螺紋端(duan)三(san)種(zhong)，大、小(xiao)端(duan)不(bu)同(tong)組(zu)合可獲得九種(zhong)配合。