20世紀50~70年代,在我國熱軋鋼管生產采用連鑄管坯前,熱軋鋼管生產所用的管坯(圓坯、方坯)均采用鋼錠軋制的管坯,如鞍鋼無縫廠、包鋼無縫廠,其管坯生產流程為:高爐鐵水→平爐煉鋼→鑄錠→初軋開坯→中大型軋機→圓坯→檢查、修磨,該生產流程是我國早期管坯生產的主要流程;成都無縫廠在煉鋼系統尚未投入之前,所用的方坯、方錠曾由重鋼、馬鋼供給,煉鋼系統(70t×4平爐)投入后,其所用方錠,由煉鋼系統提供,方坯仍由外購。
1977年成都無縫廠建成投產了我國自主設計制造的第一臺兩機四流弧形方坯連鑄機,規格為140mm×140mm、160mm×160mm,后增加185mm×185mm,用于φ133mm頂管機組生產無縫鋼管;1986年該廠建成投產了由國內設計制造的我國第一套小直徑圓管坯Φ90mm水平連鑄機;1989-1992年又同美國西馬克·康卡斯特公司聯合設計制造了φ170~350mm和φ300~450mm(預留500mm)中大直徑圓坯弧形連鑄機各一臺,由此開始了我國直接應用連鑄圓管坯生產無縫鋼管的歷史。
衡陽(yang)鋼管廠(chang)也是(shi)我國較(jiao)早采用(yong)水平連(lian)鑄(zhu)生(sheng)產(chan)(chan)(chan)(chan)(chan)管坯(pi)(pi)的企業(ye),1991年5月(yue)該廠(chang)煉鋼連(lian)鑄(zhu)生(sheng)產(chan)(chan)(chan)(chan)(chan)線(xian)建成投(tou)產(chan)(chan)(chan)(chan)(chan),配有30tx2臺(tai)電爐、3臺(tai)40tLF爐、1臺(tai)VD爐、2臺(tai)雙機(ji)雙流水平連(lian)鑄(zhu)機(ji),生(sheng)產(chan)(chan)(chan)(chan)(chan)φ80~130mm管坯(pi)(pi),是(shi)當(dang)時我國水平連(lian)鑄(zhu)生(sheng)產(chan)(chan)(chan)(chan)(chan)規模最大的廠(chang)家。
1992年6月,天津鋼管(guan)從德國全(quan)套引(yin)進的(de)150噸電爐冶煉系(xi)統(tong)建成投產(chan)。該冶煉系(xi)統(tong)配(pei)備有(you)LF、VD爐外(wai)精煉設備和(he)一機(ji)四流管(guan)坯連鑄(zhu)(zhu)機(ji),生(sheng)產(chan)φ210mm、φ270mm、φ310mm3種(zhong)規格管(guan)坯。其生(sheng)產(chan)流程為:廢鋼+海(hai)綿鐵(tie)→電爐→LF爐→VD爐→連鑄(zhu)(zhu)→圓坯→檢(jian)查。該生(sheng)產(chan)線為當(dang)時國內(nei)最先進的(de)生(sheng)產(chan)線,采(cai)用(yong)許多新技術(shu),諸如(ru):泡(pao)沫渣埋弧熔(rong)煉;偏(pian)心爐底(di)出鋼;爐蓋第五孔連續加(jia)料;LF、VD兩(liang)工位吹氬攪(jiao)拌;經VD的(de)鋼水喂絲(si)鈣(gai)處理;結晶器液面控制技術(shu);中(zhong)間包冶金技術(shu);保護澆鑄(zhu)(zhu)技術(shu);二冷水自動配(pei)水;多點矯(jiao)直技術(shu);采(cai)用(yong)多級(ji)計算(suan)機(ji)控制系(xi)統(tong),實現(xian)基礎自動化(hua)和(he)過程控制,實現(xian)各工序(xu)優化(hua)操(cao)作等。
寶鋼ф140mm機(ji)組(zu)投(tou)產后(hou),其采(cai)用(yong)的(de)管(guan)坯也(ye)是由初軋廠(chang)提供(gong)的(de)軋制管(guan)坯,直到1997年(nian)寶鋼從法國引進的(de)150t超高(gao)功率(lv)直流電(dian)弧爐、精煉及(ji)連鑄設備投(tou)產,才開始了使用(yong)連鑄管(guan)坯。
20世(shi)紀90年(nian)代以來,隨著國(guo)內主要無(wu)(wu)縫(feng)(feng)(feng)(feng)鋼(gang)管(guan)(guan)(guan)(guan)(guan)(guan)(guan)企(qi)(qi)業(ye)如攀成鋼(gang)、天津鋼(gang)管(guan)(guan)(guan)(guan)(guan)(guan)(guan)、寶鋼(gang)、華菱衡(heng)陽(yang)鋼(gang)管(guan)(guan)(guan)(guan)(guan)(guan)(guan)、湖北(bei)新(xin)冶鋼(gang)等(deng)(deng)建(jian)設的(de)超高功率大(da)電爐、爐外(wai)精(jing)煉及弧(hu)形連(lian)(lian)鑄(zhu)(zhu)機(ji)短(duan)流(liu)程生(sheng)(sheng)產(chan)(chan)(chan)線的(de)陸續(xu)投(tou)產(chan)(chan)(chan);以及包鋼(gang)鋼(gang)管(guan)(guan)(guan)(guan)(guan)(guan)(guan)、黑龍(long)江建(jian)龍(long)、林州鳳寶等(deng)(deng)轉爐+爐外(wai)精(jing)煉+連(lian)(lian)鑄(zhu)(zhu)長(chang)流(liu)程生(sheng)(sheng)產(chan)(chan)(chan)線的(de)建(jian)設,使(shi)我國(guo)無(wu)(wu)縫(feng)(feng)(feng)(feng)鋼(gang)管(guan)(guan)(guan)(guan)(guan)(guan)(guan)企(qi)(qi)業(ye)管(guan)(guan)(guan)(guan)(guan)(guan)(guan)坯(pi)(pi)(pi)生(sheng)(sheng)產(chan)(chan)(chan)的(de)裝備(bei)與(yu)工藝技術水平大(da)幅度(du)提升,管(guan)(guan)(guan)(guan)(guan)(guan)(guan)坯(pi)(pi)(pi)的(de)連(lian)(lian)鑄(zhu)(zhu)比(bi)大(da)大(da)地提高,我國(guo)熱(re)軋(ya)無(wu)(wu)縫(feng)(feng)(feng)(feng)鋼(gang)管(guan)(guan)(guan)(guan)(guan)(guan)(guan)生(sheng)(sheng)產(chan)(chan)(chan)所用的(de)管(guan)(guan)(guan)(guan)(guan)(guan)(guan)坯(pi)(pi)(pi)(除(chu)個別(bie)企(qi)(qi)業(ye)、個別(bie)品種仍采(cai)(cai)用軋(ya)坯(pi)(pi)(pi)或鍛坯(pi)(pi)(pi)外(wai)),絕大(da)部分采(cai)(cai)用連(lian)(lian)鑄(zhu)(zhu)圓(yuan)(yuan)管(guan)(guan)(guan)(guan)(guan)(guan)(guan)坯(pi)(pi)(pi)。主要設備(bei)參數(shu)見表(biao)5-1, 2017年(nian)我國(guo)無(wu)(wu)縫(feng)(feng)(feng)(feng)鋼(gang)管(guan)(guan)(guan)(guan)(guan)(guan)(guan)產(chan)(chan)(chan)量(liang)(liang)(liang)2017.2萬(wan)噸,其中重點企(qi)(qi)業(ye)熱(re)軋(ya)管(guan)(guan)(guan)(guan)(guan)(guan)(guan)產(chan)(chan)(chan)量(liang)(liang)(liang)約(yue)1050萬(wan)噸。從鋼(gang)管(guan)(guan)(guan)(guan)(guan)(guan)(guan)分會(hui)統計(ji)的(de)數(shu)據(ju)看,約(yue)70%的(de)無(wu)(wu)縫(feng)(feng)(feng)(feng)鋼(gang)管(guan)(guan)(guan)(guan)(guan)(guan)(guan)(指熱(re)軋(ya))采(cai)(cai)用連(lian)(lian)鑄(zhu)(zhu)圓(yuan)(yuan)管(guan)(guan)(guan)(guan)(guan)(guan)(guan)坯(pi)(pi)(pi)生(sheng)(sheng)產(chan)(chan)(chan),約(yue)30%的(de)無(wu)(wu)縫(feng)(feng)(feng)(feng)鋼(gang)管(guan)(guan)(guan)(guan)(guan)(guan)(guan)(指冷(leng)拔/冷(leng)軋(ya)+極少量(liang)(liang)(liang)熱(re)軋(ya))采(cai)(cai)用軋(ya)制(zhi)圓(yuan)(yuan)管(guan)(guan)(guan)(guan)(guan)(guan)(guan)坯(pi)(pi)(pi)和(he)其他管(guan)(guan)(guan)(guan)(guan)(guan)(guan)坯(pi)(pi)(pi)生(sheng)(sheng)產(chan)(chan)(chan)。我國(guo)連(lian)(lian)鑄(zhu)(zhu)圓(yuan)(yuan)坯(pi)(pi)(pi)生(sheng)(sheng)產(chan)(chan)(chan)無(wu)(wu)縫(feng)(feng)(feng)(feng)鋼(gang)管(guan)(guan)(guan)(guan)(guan)(guan)(guan)已成為無(wu)(wu)縫(feng)(feng)(feng)(feng)鋼(gang)管(guan)(guan)(guan)(guan)(guan)(guan)(guan)生(sheng)(sheng)產(chan)(chan)(chan)的(de)主流(liu),管(guan)(guan)(guan)(guan)(guan)(guan)(guan)壞生(sheng)(sheng)產(chan)(chan)(chan)工藝與(yu)技術的(de)進(jin)步(bu),使(shi)連(lian)(lian)鑄(zhu)(zhu)管(guan)(guan)(guan)(guan)(guan)(guan)(guan)坯(pi)(pi)(pi)的(de)規格、品種與(yu)質量(liang)(liang)(liang)等(deng)(deng)方面都得到快速(su)發展(zhan)。
2010年以來,我國自(zi)主制造(zao)的連(lian)鑄(zhu)機(ji)在技術裝備(bei)和生(sheng)(sheng)產(chan)(chan)(chan)的產(chan)(chan)(chan)品檔次方面有了很大(da)(da)(da)的進步,特別是超大(da)(da)(da)規(gui)格(ge)的圓坯(pi)連(lian)鑄(zhu)生(sheng)(sheng)產(chan)(chan)(chan),相(xiang)繼(ji)創造(zao)新紀錄,已(yi)(yi)批量生(sheng)(sheng)產(chan)(chan)(chan)500~1000mm的大(da)(da)(da)規(gui)格(ge)圓坯(pi)(如(ru)華菱衡陽鋼管(guan)生(sheng)(sheng)產(chan)(chan)(chan)出(chu)Φ500mm、Φ600mm、Φ700mm、φ800mm大(da)(da)(da)圓坯(pi)),產(chan)(chan)(chan)品質量優良,屬國內(nei)外(wai)(wai)高水平。超大(da)(da)(da)規(gui)格(ge)的圓坯(pi)代替(ti)模鑄(zhu),大(da)(da)(da)幅度提高成(cheng)(cheng)材率,降低了生(sheng)(sheng)產(chan)(chan)(chan)成(cheng)(cheng)本,生(sheng)(sheng)產(chan)(chan)(chan)效益得(de)到很大(da)(da)(da)提高。國產(chan)(chan)(chan)連(lian)鑄(zhu)裝備(bei)不僅在國內(nei)已(yi)(yi)經具(ju)備(bei)與外(wai)(wai)商同臺競(jing)爭的實力,而且已(yi)(yi)經實現成(cheng)(cheng)套出(chu)口(kou)。
連鑄(zhu)圓(yuan)坯(pi)不(bu)僅廣(guang)泛應用(yong)(yong)于無縫鋼管管坯(pi),而且(qie)在鍛造行業也得到廣(guang)泛應用(yong)(yong),尤其(qi)是(shi)大(da)型鍛件,例如法蘭、大(da)直徑齒圈(quan)、石油鉆(zhan)鋌、大(da)型桿件等。我國許(xu)多鋼廠(chang)都在圓(yuan)坯(pi)連鑄(zhu)生產上有(you)所涉(she)及,如:
(1)興澄特(te)鋼(gang)大圓坯連鑄機生產的Φ600mm、φ800mm、Φ1000mm圓坯;
(2)淮(huai)鋼大圓坯鑄機(ji)生產的Φ380mm、Φ450mm、φ500mm、φ600mm圓坯;
(3)中原特鋼立式(shi)連鑄機生產(chan)的Φ400mm、φ600mm、φ800mm圓坯;
(4)承德建龍生(sheng)產的φ300mm、φ500mm圓(yuan)坯。
上述(shu)企業生(sheng)產的管(guan)坯均能滿(man)足鋼(gang)管(guan)生(sheng)產、棒材型(xing)材生(sheng)產、鍛壓生(sheng)產(法蘭、環鍛、機械桿件(jian))等的需求(qiu)。