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隨著石油(you)(you)(you)(you)工(gong)業(ye)的發展 ,對油(you)(you)(you)(you)管的需求(qiu)(qiu)量與日俱(ju)增。油(you)(you)(you)(you)管服役(yi)條(tiao)件(jian)惡劣 ,導致(zhi)油(you)(you)(you)(you)管普遍存在如下缺陷 :滑脫、管體破裂、穿(chuan)孔、錯(cuo)斷、偏磨(mo)、腐蝕坑等(deng)。為保(bao)證(zheng)油(you)(you)(you)(you)管在工(gong)作(zuo)時的高性(xing)(xing)能 ,必須對油(you)(you)(you)(you)管的外(wai)型尺寸、機械性(xing)(xing)能、內外(wai)表(biao)面狀(zhuang)態及螺紋(wen)連接的性(xing)(xing)能進行嚴格的檢查。油(you)(you)(you)(you)管是指石油(you)(you)(you)(you)油(you)(you)(you)(you)井用無(wu)縫管。制(zhi)(zhi)造(zao)方(fang)法與無(wu)縫管相同(tong)，國內用DZ(地(di)質)35～DZ55等(deng)鋼(gang)制(zhi)(zhi)造(zao)。鋼(gang)管兩端車有螺紋(wen)，以便用接頭聯結。為保(bao)證(zheng)接頭處(chu)的密封性(xing)(xing)，對螺紋(wen)精度(du)有較嚴格的要(yao)求(qiu)(qiu)。