凡(fan)是兩端開口并具有(you)中(zhong)空(kong)斷(duan)(duan)面(mian)(mian)，而且(qie)其(qi)長度與斷(duan)(duan)面(mian)(mian)周(zhou)長之(zhi)(zhi)比(bi)較(jiao)大(da)的(de)(de)(de)(de)(de)(de)鋼(gang)(gang)材(cai)(cai)，都可(ke)以稱為鋼(gang)(gang)管(guan)(guan)(guan)。當長度與斷(duan)(duan)面(mian)(mian)周(zhou)長之(zhi)(zhi)比(bi)較(jiao)小時，可(ke)稱為管(guan)(guan)(guan)段或(huo)管(guan)(guan)(guan)形配(pei)件(jian)(jian)，它(ta)(ta)們都屬于管(guan)(guan)(guan)材(cai)(cai)產(chan)品的(de)(de)(de)(de)(de)(de)范(fan)(fan)疇。鋼(gang)(gang)管(guan)(guan)(guan)是一種(zhong)(zhong)經濟(ji)(ji)斷(duan)(duan)面(mian)(mian)鋼(gang)(gang)材(cai)(cai)，是鋼(gang)(gang)鐵(tie)工(gong)業(ye)中(zhong)的(de)(de)(de)(de)(de)(de)一項重(zhong)要(yao)(yao)產(chan)品，通常占全部(bu)鋼(gang)(gang)材(cai)(cai)總(zong)量(liang)的(de)(de)(de)(de)(de)(de)8%~16%左右，它(ta)(ta)在國民經濟(ji)(ji)中(zhong)的(de)(de)(de)(de)(de)(de)應用(yong)范(fan)(fan)圍極為廣(guang)泛(fan)。由于鋼(gang)(gang)管(guan)(guan)(guan)具有(you)空(kong)心斷(duan)(duan)面(mian)(mian)，因而最適合(he)作(zuo)液體、氣體和固體的(de)(de)(de)(de)(de)(de)輸送管(guan)(guan)(guan)道；同(tong)時與相同(tong)重(zhong)量(liang)的(de)(de)(de)(de)(de)(de)圓鋼(gang)(gang)比(bi)較(jiao)，鋼(gang)(gang)管(guan)(guan)(guan)的(de)(de)(de)(de)(de)(de)斷(duan)(duan)面(mian)(mian)系(xi)數大(da)、抗彎抗扭強度大(da)，所以也(ye)成(cheng)為各種(zhong)(zhong)機械和建(jian)筑(zhu)結構(gou)上的(de)(de)(de)(de)(de)(de)重(zhong)要(yao)(yao)材(cai)(cai)料(liao)。用(yong)鋼(gang)(gang)管(guan)(guan)(guan)制成(cheng)的(de)(de)(de)(de)(de)(de)結構(gou)和部(bu)件(jian)(jian)，在重(zhong)量(liang)相等(deng)的(de)(de)(de)(de)(de)(de)情況(kuang)下，比(bi)實心零部(bu)件(jian)(jian)具有(you)更(geng)大(da)的(de)(de)(de)(de)(de)(de)截(jie)面(mian)(mian)模(mo)數。所以，鋼(gang)(gang)管(guan)(guan)(guan)本身(shen)就(jiu)是一種(zhong)(zhong)節約金屬的(de)(de)(de)(de)(de)(de)經濟(ji)(ji)斷(duan)(duan)面(mian)(mian)鋼(gang)(gang)材(cai)(cai)，它(ta)(ta)是高效鋼(gang)(gang)材(cai)(cai)的(de)(de)(de)(de)(de)(de)一個重(zhong)要(yao)(yao)組成(cheng)部(bu)分(fen)，尤其(qi)在石油鉆采、冶煉和輸送等(deng)行業(ye)需求較(jiao)大(da)，其(qi)次地質鉆探、化工(gong)、建(jian)筑(zhu)工(gong)業(ye)、機械工(gong)業(ye)、飛(fei)機和汽車(che)制造(zao)以及(ji)鍋爐、醫(yi)療器械、家具和自行車(che)制造(zao)等(deng)方面(mian)(mian)也(ye)都需要(yao)(yao)大(da)量(liang)的(de)(de)(de)(de)(de)(de)各種(zhong)(zhong)鋼(gang)(gang)管(guan)(guan)(guan)。近年(nian)來，隨著原子(zi)能、火箭、導彈和航天工(gong)業(ye)等(deng)新(xin)技(ji)術的(de)(de)(de)(de)(de)(de)發展，鋼(gang)(gang)管(guan)(guan)(guan)在國防工(gong)業(ye)、科學技(ji)術和經濟(ji)(ji)建(jian)設(she)中(zhong)的(de)(de)(de)(de)(de)(de)地位愈加重(zhong)要(yao)(yao)。

  鋼(gang)管(guan)的種(zhong)類(lei)繁多，用途不(bu)(bu)同，其(qi)技術(shu)要求(qiu)各異，生產方法亦有所不(bu)(bu)同。目(mu)前生產的鋼(gang)管(guan)外徑范(fan)(fan)圍0.1~4500mm、壁厚范(fan)(fan)圍0.01~250mm.為了區分其(qi)特點，通常按如下的方法對鋼(gang)管(guan)進行分類(lei)。

1. 按生產方式分類

  鋼管(guan)(guan)(guan)按生產方式(shi)分為(wei)無縫(feng)管(guan)(guan)(guan)和(he)焊(han)管(guan)(guan)(guan)兩(liang)大(da)類，無縫(feng)鋼管(guan)(guan)(guan)又可(ke)分為(wei)熱軋(ya)管(guan)(guan)(guan)，冷(leng)軋(ya)管(guan)(guan)(guan)、冷(leng)拔管(guan)(guan)(guan)和(he)擠壓管(guan)(guan)(guan)等，冷(leng)拔、冷(leng)軋(ya)是鋼管(guan)(guan)(guan)的二次加(jia)工；焊(han)管(guan)(guan)(guan)分為(wei)直縫(feng)焊(han)管(guan)(guan)(guan)和(he)螺(luo)旋(xuan)焊(han)管(guan)(guan)(guan)等。

2. 按鋼管的斷面形狀分類

  鋼(gang)管(guan)(guan)(guan)(guan)按橫(heng)斷面(mian)(mian)形(xing)狀可(ke)(ke)分為圓管(guan)(guan)(guan)(guan)和(he)(he)異形(xing)管(guan)(guan)(guan)(guan)。異形(xing)管(guan)(guan)(guan)(guan)有(you)矩形(xing)管(guan)(guan)(guan)(guan)、菱形(xing)管(guan)(guan)(guan)(guan)、橢圓管(guan)(guan)(guan)(guan)、六方管(guan)(guan)(guan)(guan)、八方管(guan)(guan)(guan)(guan)以及(ji)各(ge)(ge)種斷面(mian)(mian)不對(dui)稱管(guan)(guan)(guan)(guan)等。異形(xing)管(guan)(guan)(guan)(guan)廣泛用于各(ge)(ge)種結(jie)構件(jian)、工具和(he)(he)機械零部(bu)件(jian)。與圓管(guan)(guan)(guan)(guan)相比，異形(xing)管(guan)(guan)(guan)(guan)一般都有(you)較大的慣性矩和(he)(he)截(jie)面(mian)(mian)模數(shu)，有(you)較大的抗(kang)彎、抗(kang)扭能力，可(ke)(ke)以大大減(jian)輕(qing)結(jie)構重量，節約鋼(gang)材。

  鋼管(guan)(guan)(guan)按縱斷(duan)(duan)面(mian)形(xing)狀可(ke)分為等(deng)斷(duan)(duan)面(mian)管(guan)(guan)(guan)和(he)變斷(duan)(duan)面(mian)管(guan)(guan)(guan)。變斷(duan)(duan)面(mian)管(guan)(guan)(guan)有錐形(xing)管(guan)(guan)(guan)、階梯形(xing)管(guan)(guan)(guan)和(he)周(zhou)期斷(duan)(duan)面(mian)管(guan)(guan)(guan)等(deng)。

3. 按鋼管的材質分類

  鋼管按材質分為普通碳素鋼管、優質碳素結構鋼管、合金結構管、合金鋼管、軸承鋼管、不銹鋼管以及為節省貴重金屬和滿足特殊要求的雙金屬復合管、鍍層和涂層管等。

4. 按管端形(xing)狀分(fen)類(lei)

  鋼管(guan)(guan)根據管(guan)(guan)端(duan)狀態可分為(wei)光管(guan)(guan)和車(che)絲(si)(si)(si)管(guan)(guan)（帶螺(luo)(luo)紋(wen)鋼管(guan)(guan)）。車(che)絲(si)(si)(si)管(guan)(guan)又可分為(wei)普通車(che)絲(si)(si)(si)管(guan)(guan)（輸(shu)送水、煤氣等低壓用(yong)管(guan)(guan)，采用(yong)普通圓柱(zhu)或圓錐管(guan)(guan)螺(luo)(luo)紋(wen)連接(jie)）和特殊(shu)螺(luo)(luo)紋(wen)管(guan)(guan)（石油、地質鉆探用(yong)管(guan)(guan)，對于重(zhong)要的車(che)絲(si)(si)(si)管(guan)(guan)，采用(yong)特殊(shu)螺(luo)(luo)紋(wen)連接(jie)），對一些特殊(shu)用(yong)管(guan)(guan)，為(wei)彌補螺(luo)(luo)紋(wen)對管(guan)(guan)端(duan)強(qiang)度的影響，通常在(zai)車(che)絲(si)(si)(si)前(qian)先進行管(guan)(guan)端(duan)加厚(hou)（內加厚(hou)、外(wai)加厚(hou)或內外(wai)加厚(hou)）。

5. 按外(wai)徑D和壁(bi)厚S之比（D/S)分類(lei)

  按外徑D和壁(bi)厚(hou)S之比的(de)不同將鋼管分為特厚(hou)管（D/S≤10)、厚(hou)壁(bi)管（D/S=10~20)、薄(bo)壁(bi)管（D/S=20~40)和極薄(bo)壁(bi)管（D/S≥40)。

6. 按用途分(fen)類

  按(an)用(yong)途可分為油井管(guan)(guan)（套管(guan)(guan)、油管(guan)(guan)及鉆桿等）、管(guan)(guan)線管(guan)(guan)、鍋爐管(guan)(guan)、機械結構管(guan)(guan)、液壓支柱管(guan)(guan)、氣瓶(ping)管(guan)(guan)、地(di)質(zhi)管(guan)(guan)、化工用(yong)管(guan)(guan)（高壓化肥管(guan)(guan)、石(shi)油裂化管(guan)(guan)）和船舶用(yong)管(guan)(guan)等。