無(wu)縫方(fang)矩管(guan)(guan)(guan)(guan)(guan)(guan)是一(yi)種具(ju)有中空截面(mian)周邊(bian)沒有接縫的(de)長條(tiao)(tiao)鋼材。用(yong)(yong)鋼管(guan)(guan)(guan)(guan)(guan)(guan)制(zhi)(zhi)造(zao)環形零件(jian)，可(ke)提高材料利用(yong)(yong)率(lv)，簡化制(zhi)(zhi)造(zao)工(gong)序(xu)，節約材料和加工(gong)工(gong)時(shi)，如(ru)滾動軸承(cheng)套圈、千斤頂套等(deng)，當前已(yi)廣泛用(yong)(yong)鋼管(guan)(guan)(guan)(guan)(guan)(guan)來(lai)制(zhi)(zhi)造(zao)。鋼管(guan)(guan)(guan)(guan)(guan)(guan)還是各種常(chang)規武器不(bu)可(ke)缺少的(de)材料，槍管(guan)(guan)(guan)(guan)(guan)(guan)、炮筒等(deng)都要鋼管(guan)(guan)(guan)(guan)(guan)(guan)來(lai)制(zhi)(zhi)造(zao)。鋼管(guan)(guan)(guan)(guan)(guan)(guan)按橫截面(mian)積形狀(zhuang)的(de)不(bu)同可(ke)分(fen)為圓(yuan)(yuan)(yuan)管(guan)(guan)(guan)(guan)(guan)(guan)和異(yi)型(xing)管(guan)(guan)(guan)(guan)(guan)(guan)。由于在周長相等(deng)的(de)條(tiao)(tiao)件(jian)下，圓(yuan)(yuan)(yuan)面(mian)積 ，用(yong)(yong)圓(yuan)(yuan)(yuan)形管(guan)(guan)(guan)(guan)(guan)(guan)可(ke)以(yi)輸送(song)更(geng)多(duo)的(de)流體。此(ci)外，圓(yuan)(yuan)(yuan)環截面(mian)在承(cheng)受內(nei)部或外部徑向壓力(li)時(shi)，受力(li)較均(jun)勻，因此(ci)，絕大多(duo)數鋼管(guan)(guan)(guan)(guan)(guan)(guan)是圓(yuan)(yuan)(yuan)管(guan)(guan)(guan)(guan)(guan)(guan)。但(dan)是，圓(yuan)(yuan)(yuan)管(guan)(guan)(guan)(guan)(guan)(guan)也有一(yi)定的(de)局(ju)限性，如(ru)在受平面(mian)彎曲的(de)條(tiao)(tiao)件(jian)下，圓(yuan)(yuan)(yuan)管(guan)(guan)(guan)(guan)(guan)(guan)就不(bu)如(ru)方(fang)、矩形管(guan)(guan)(guan)(guan)(guan)(guan)抗彎強度(du)大，一(yi)些農機具(ju)骨架(jia)(jia)、鋼木家具(ju)等(deng)就常(chang)用(yong)(yong)方(fang)、矩形管(guan)(guan)(guan)(guan)(guan)(guan)。根據不(bu)同用(yong)(yong)方(fang)管(guan)(guan)(guan)(guan)(guan)(guan)的(de)力(li)學(xue)性能[1]  石油鉆桿、汽(qi)車傳(chuan)動軸、自行車架(jia)(jia)以(yi)及(ji)建筑施工(gong)中用(yong)(yong)的(de)鋼腳手(shou)架(jia)(jia)等(deng)。