連續軋管機是在毛管內穿入長芯棒后,經過多機架順序布置且相鄰機架輥縫互錯(二輥式輥縫互錯90°如圖4-1所示,三輥式輥縫互錯60°)的連軋機軋成不銹鋼管,它是當今最為廣泛使用的縱軋不(bu)銹鋼管(guan)方法。在連續軋管機軋制過程中,軋件變形實際上是受多組(4~8組)軋輥與芯棒的反復作用從圓到橢圓···橢圓再到圓的過程。
連(lian)續(xu)(xu)軋(ya)(ya)(ya)(ya)(ya)管(guan)機(ji)的發(fa)展歷史悠久,早在19世紀(ji)末就(jiu)曾嘗試在長芯棒上(shang)進(jin)行(xing)軋(ya)(ya)(ya)(ya)(ya)管(guan),但由(you)于(yu)種(zhong)種(zhong)原因,至1950年世界(jie)上(shang)也僅有(you)6臺連(lian)續(xu)(xu)軋(ya)(ya)(ya)(ya)(ya)管(guan)機(ji)。1960年后(hou),隨著科學技(ji)(ji)(ji)術(shu)的進(jin)步(bu)和生產(chan)的發(fa)展,特別是電子計(ji)算(suan)機(ji)技(ji)(ji)(ji)術(shu)的飛(fei)速發(fa)展和應用,使連(lian)續(xu)(xu)軋(ya)(ya)(ya)(ya)(ya)管(guan)機(ji)在生產(chan)工(gong)藝和設備上(shang)日趨完(wan)善,得到了(le)迅(xun)速的發(fa)展和推廣。在浮動(dong)芯棒連(lian)續(xu)(xu)軋(ya)(ya)(ya)(ya)(ya)管(guan)機(ji)的基礎(chu)上(shang),限動(dong)芯棒連(lian)續(xu)(xu)軋(ya)(ya)(ya)(ya)(ya)管(guan)機(ji)于(yu)20世紀(ji)60年代中期進(jin)行(xing)了(le)工(gong)藝試驗(yan),獲(huo)得了(le)可喜(xi)的成果。1978年世界(jie)上(shang)第一套限動(dong)芯棒連(lian)續(xu)(xu)軋(ya)(ya)(ya)(ya)(ya)管(guan)機(ji)(MPM)在意大(da)利達爾明鋼管(guan)廠(chang)建成投產(chan),連(lian)續(xu)(xu)軋(ya)(ya)(ya)(ya)(ya)管(guan)工(gong)藝發(fa)展到了(le)一個新(xin)的水準(zhun)。20世紀(ji)90年代末又推出了(le)三(san)輥連(lian)續(xu)(xu)軋(ya)(ya)(ya)(ya)(ya)管(guan)機(ji)(PQF)技(ji)(ji)(ji)術(shu),使連(lian)續(xu)(xu)軋(ya)(ya)(ya)(ya)(ya)管(guan)工(gong)藝裝(zhuang)備躍上(shang)了(le)更高的臺階。
連(lian)續(xu)(xu)軋(ya)(ya)管(guan)機在PQF出現以前,都是兩(liang)輥(gun)(gun)(gun)式(shi)(shi)的(de)(de)(de),即(ji)由(you)兩(liang)個(ge)軋(ya)(ya)輥(gun)(gun)(gun)為一組(zu)(zu)組(zu)(zu)成孔(kong)型,二輥(gun)(gun)(gun)式(shi)(shi)的(de)(de)(de)機架(jia)既有與(yu)地面呈45°交(jiao)錯布(bu)置的(de)(de)(de),也有與(yu)地面垂直、水平(ping)交(jiao)錯布(bu)置的(de)(de)(de)。PQF為三(san)(san)輥(gun)(gun)(gun)式(shi)(shi)的(de)(de)(de),即(ji)由(you)三(san)(san)個(ge)軋(ya)(ya)輥(gun)(gun)(gun)為一組(zu)(zu)組(zu)(zu)成孔(kong)型,如(ru)圖4-2所示。連(lian)續(xu)(xu)軋(ya)(ya)管(guan)時(shi),孔(kong)型頂部(bu)(bu)的(de)(de)(de)金屬由(you)于受到軋(ya)(ya)輥(gun)(gun)(gun)外壓力和(he)芯(xin)(xin)棒(bang)(bang)(bang)內(nei)壓力作用而產(chan)生(sheng)(sheng)軸向(xiang)(xiang)(xiang)延伸,并向(xiang)(xiang)(xiang)圓周橫向(xiang)(xiang)(xiang)寬展,而孔(kong)型側壁(bi)部(bu)(bu)分的(de)(de)(de)金屬與(yu)芯(xin)(xin)棒(bang)(bang)(bang)不接觸,但它被頂部(bu)(bu)軸向(xiang)(xiang)(xiang)延伸的(de)(de)(de)金屬對它附加的(de)(de)(de)拉應力作用而產(chan)生(sheng)(sheng)軸向(xiang)(xiang)(xiang)延伸,并同時(shi)產(chan)生(sheng)(sheng)軸向(xiang)(xiang)(xiang)拉縮。不論(lun)兩(liang)輥(gun)(gun)(gun)式(shi)(shi)的(de)(de)(de)還是三(san)(san)輥(gun)(gun)(gun)式(shi)(shi)的(de)(de)(de)連(lian)續(xu)(xu)軋(ya)(ya)管(guan)機,按芯(xin)(xin)棒(bang)(bang)(bang)的(de)(de)(de)運行(xing)方式(shi)(shi)可分為浮(fu)動(dong)芯(xin)(xin)棒(bang)(bang)(bang)連(lian)續(xu)(xu)軋(ya)(ya)管(guan)機、半浮(fu)動(dong)芯(xin)(xin)棒(bang)(bang)(bang)連(lian)續(xu)(xu)軋(ya)(ya)管(guan)機和(he)限動(dong)芯(xin)(xin)棒(bang)(bang)(bang)連(lian)續(xu)(xu)軋(ya)(ya)管(guan)機三(san)(san)種形式(shi)(shi)。
為了完成(cheng)將(jiang)連續軋管(guan)機軋出(chu)的荒管(guan)與芯棒(bang)脫開分離(li)的工藝(yi)目的,便于荒管(guan)在后道工序進一步加工成(cheng)品不銹鋼管(guan),一般采用以(yi)下(xia)兩種方法。
1. 脫棒(bang)機
軋(ya)(ya)制結束后荒(huang)管(guan)(guan)/芯(xin)(xin)(xin)(xin)(xin)(xin)棒(bang)(bang)(bang)(bang)(bang)(bang)(bang)(bang)被(bei)一起移出(chu)(chu)軋(ya)(ya)制線,荒(huang)管(guan)(guan)受(shou)軸(zhou)向(xiang)約束不(bu)動(dong),用(yong)(yong)裝(zhuang)置(zhi)(zhi)(zhi)將(jiang)芯(xin)(xin)(xin)(xin)(xin)(xin)棒(bang)(bang)(bang)(bang)(bang)(bang)(bang)(bang)從荒(huang)管(guan)(guan)中抽(chou)出(chu)(chu)。我們將(jiang)這種荒(huang)管(guan)(guan)不(bu)動(dong),芯(xin)(xin)(xin)(xin)(xin)(xin)棒(bang)(bang)(bang)(bang)(bang)(bang)(bang)(bang)動(dong)的(de)設備稱為(wei)(wei)脫(tuo)(tuo)(tuo)(tuo)(tuo)(tuo)棒(bang)(bang)(bang)(bang)(bang)(bang)(bang)(bang)機(ji)。當帶芯(xin)(xin)(xin)(xin)(xin)(xin)棒(bang)(bang)(bang)(bang)(bang)(bang)(bang)(bang)的(de)荒(huang)管(guan)(guan)進入脫(tuo)(tuo)(tuo)(tuo)(tuo)(tuo)棒(bang)(bang)(bang)(bang)(bang)(bang)(bang)(bang)位(wei)(wei)置(zhi)(zhi)(zhi)后,脫(tuo)(tuo)(tuo)(tuo)(tuo)(tuo)棒(bang)(bang)(bang)(bang)(bang)(bang)(bang)(bang)鏈(lian)上的(de)脫(tuo)(tuo)(tuo)(tuo)(tuo)(tuo)棒(bang)(bang)(bang)(bang)(bang)(bang)(bang)(bang)卡(ka)緊裝(zhuang)置(zhi)(zhi)(zhi)就鉤住芯(xin)(xin)(xin)(xin)(xin)(xin)棒(bang)(bang)(bang)(bang)(bang)(bang)(bang)(bang)的(de)尾柄,而液壓(ya)開閉的(de)卡(ka)板擋住荒(huang)管(guan)(guan),脫(tuo)(tuo)(tuo)(tuo)(tuo)(tuo)棒(bang)(bang)(bang)(bang)(bang)(bang)(bang)(bang)鏈(lian)從荒(huang)管(guan)(guan)中抽(chou)出(chu)(chu)芯(xin)(xin)(xin)(xin)(xin)(xin)棒(bang)(bang)(bang)(bang)(bang)(bang)(bang)(bang)。脫(tuo)(tuo)(tuo)(tuo)(tuo)(tuo)棒(bang)(bang)(bang)(bang)(bang)(bang)(bang)(bang)鏈(lian)轉(zhuan)過(guo)半圈完成一次脫(tuo)(tuo)(tuo)(tuo)(tuo)(tuo)棒(bang)(bang)(bang)(bang)(bang)(bang)(bang)(bang)動(dong)作,鏈(lian)所(suo)走過(guo)的(de)距離(li)約為(wei)(wei)芯(xin)(xin)(xin)(xin)(xin)(xin)棒(bang)(bang)(bang)(bang)(bang)(bang)(bang)(bang)長度(du)的(de)1.1倍。脫(tuo)(tuo)(tuo)(tuo)(tuo)(tuo)棒(bang)(bang)(bang)(bang)(bang)(bang)(bang)(bang)機(ji)的(de)最大速度(du)大于(yu)4.5m/s,到達終位(wei)(wei)的(de)誤差為(wei)(wei)±50mm.脫(tuo)(tuo)(tuo)(tuo)(tuo)(tuo)出(chu)(chu)的(de)芯(xin)(xin)(xin)(xin)(xin)(xin)棒(bang)(bang)(bang)(bang)(bang)(bang)(bang)(bang)經輸送(song)輥(gun)道送(song)到芯(xin)(xin)(xin)(xin)(xin)(xin)棒(bang)(bang)(bang)(bang)(bang)(bang)(bang)(bang)定位(wei)(wei)升降擋板前,然后由芯(xin)(xin)(xin)(xin)(xin)(xin)棒(bang)(bang)(bang)(bang)(bang)(bang)(bang)(bang)移送(song)裝(zhuang)置(zhi)(zhi)(zhi)把芯(xin)(xin)(xin)(xin)(xin)(xin)棒(bang)(bang)(bang)(bang)(bang)(bang)(bang)(bang)送(song)人(ren)芯(xin)(xin)(xin)(xin)(xin)(xin)棒(bang)(bang)(bang)(bang)(bang)(bang)(bang)(bang)冷卻槽(cao),循環使用(yong)(yong)。脫(tuo)(tuo)(tuo)(tuo)(tuo)(tuo)棒(bang)(bang)(bang)(bang)(bang)(bang)(bang)(bang)機(ji)安(an)裝(zhuang)位(wei)(wei)置(zhi)(zhi)(zhi)與連續軋(ya)(ya)管(guan)(guan)機(ji)平行。脫(tuo)(tuo)(tuo)(tuo)(tuo)(tuo)棒(bang)(bang)(bang)(bang)(bang)(bang)(bang)(bang)機(ji)有兩(liang)(liang)(liang)列(lie)(lie)脫(tuo)(tuo)(tuo)(tuo)(tuo)(tuo)棒(bang)(bang)(bang)(bang)(bang)(bang)(bang)(bang)鏈(lian),這兩(liang)(liang)(liang)列(lie)(lie)脫(tuo)(tuo)(tuo)(tuo)(tuo)(tuo)棒(bang)(bang)(bang)(bang)(bang)(bang)(bang)(bang)鏈(lian)用(yong)(yong)橫(heng)梁(liang)(liang)連接起來,兩(liang)(liang)(liang)列(lie)(lie)脫(tuo)(tuo)(tuo)(tuo)(tuo)(tuo)棒(bang)(bang)(bang)(bang)(bang)(bang)(bang)(bang)鏈(lian)間共有兩(liang)(liang)(liang)個(ge)脫(tuo)(tuo)(tuo)(tuo)(tuo)(tuo)棒(bang)(bang)(bang)(bang)(bang)(bang)(bang)(bang)橫(heng)梁(liang)(liang)及(ji)多個(ge)承(cheng)載橫(heng)梁(liang)(liang)。脫(tuo)(tuo)(tuo)(tuo)(tuo)(tuo)棒(bang)(bang)(bang)(bang)(bang)(bang)(bang)(bang)橫(heng)梁(liang)(liang)用(yong)(yong)來從荒(huang)管(guan)(guan)中抽(chou)出(chu)(chu)芯(xin)(xin)(xin)(xin)(xin)(xin)棒(bang)(bang)(bang)(bang)(bang)(bang)(bang)(bang),而承(cheng)載橫(heng)梁(liang)(liang)用(yong)(yong)來在(zai)脫(tuo)(tuo)(tuo)(tuo)(tuo)(tuo)棒(bang)(bang)(bang)(bang)(bang)(bang)(bang)(bang)過(guo)程(cheng)中支(zhi)撐芯(xin)(xin)(xin)(xin)(xin)(xin)棒(bang)(bang)(bang)(bang)(bang)(bang)(bang)(bang)。在(zai)脫(tuo)(tuo)(tuo)(tuo)(tuo)(tuo)棒(bang)(bang)(bang)(bang)(bang)(bang)(bang)(bang)橫(heng)梁(liang)(liang)上用(yong)(yong)螺栓緊固與軋(ya)(ya)件尺寸相關的(de)脫(tuo)(tuo)(tuo)(tuo)(tuo)(tuo)棒(bang)(bang)(bang)(bang)(bang)(bang)(bang)(bang)卡(ka)緊裝(zhuang)置(zhi)(zhi)(zhi),當更換軋(ya)(ya)制芯(xin)(xin)(xin)(xin)(xin)(xin)棒(bang)(bang)(bang)(bang)(bang)(bang)(bang)(bang)時,需要更換脫(tuo)(tuo)(tuo)(tuo)(tuo)(tuo)棒(bang)(bang)(bang)(bang)(bang)(bang)(bang)(bang)卡(ka)緊裝(zhuang)置(zhi)(zhi)(zhi)。
2. 脫管(guan)機
軋(ya)(ya)(ya)制(zhi)結束后(hou),芯棒(bang)(bang)(bang)停(ting)止運動(dong),荒(huang)管(guan)(guan)(guan)在(zai)線被脫(tuo)(tuo)(tuo)(tuo)(tuo)(tuo)管(guan)(guan)(guan)裝置將(jiang)其(qi)從(cong)芯棒(bang)(bang)(bang)中(zhong)脫(tuo)(tuo)(tuo)(tuo)(tuo)(tuo)出(chu)(chu),我們將(jiang)這種芯棒(bang)(bang)(bang)不動(dong),荒(huang)管(guan)(guan)(guan)動(dong)的(de)(de)(de)(de)(de)(de)設(she)(she)(she)備稱為脫(tuo)(tuo)(tuo)(tuo)(tuo)(tuo)管(guan)(guan)(guan)機(ji)(ji)(ji)(ji)(ji)(ji)。脫(tuo)(tuo)(tuo)(tuo)(tuo)(tuo)管(guan)(guan)(guan)機(ji)(ji)(ji)(ji)(ji)(ji)既有(you)兩(liang)輥(gun)式(shi)的(de)(de)(de)(de)(de)(de),也(ye)(ye)有(you)三輥(gun)式(shi)的(de)(de)(de)(de)(de)(de)。脫(tuo)(tuo)(tuo)(tuo)(tuo)(tuo)管(guan)(guan)(guan)機(ji)(ji)(ji)(ji)(ji)(ji)的(de)(de)(de)(de)(de)(de)設(she)(she)(she)置有(you)兩(liang)個重要的(de)(de)(de)(de)(de)(de)工藝目的(de)(de)(de)(de)(de)(de):(1)將(jiang)荒(huang)管(guan)(guan)(guan)從(cong)芯棒(bang)(bang)(bang)上脫(tuo)(tuo)(tuo)(tuo)(tuo)(tuo)出(chu)(chu),完成脫(tuo)(tuo)(tuo)(tuo)(tuo)(tuo)管(guan)(guan)(guan)目的(de)(de)(de)(de)(de)(de),在(zai)軋(ya)(ya)(ya)制(zhi)線上脫(tuo)(tuo)(tuo)(tuo)(tuo)(tuo)管(guan)(guan)(guan),省去了(le)脫(tuo)(tuo)(tuo)(tuo)(tuo)(tuo)棒(bang)(bang)(bang)機(ji)(ji)(ji)(ji)(ji)(ji),縮短了(le)工藝流程,提高了(le)終軋(ya)(ya)(ya)溫度;(2)起定(ding)徑(jing)(jing)作用(yong),也(ye)(ye)就是(shi)說在(zai)每(mei)(mei)一支鋼管(guan)(guan)(guan)生(sheng)產(chan)(chan)中(zhong),該機(ji)(ji)(ji)(ji)(ji)(ji)也(ye)(ye)有(you)延(yan)伸(shen)和(he)定(ding)徑(jing)(jing)作用(yong)。在(zai)早(zao)期設(she)(she)(she)計的(de)(de)(de)(de)(de)(de)限動(dong)芯棒(bang)(bang)(bang)連續軋(ya)(ya)(ya)管(guan)(guan)(guan)機(ji)(ji)(ji)(ji)(ji)(ji)組中(zhong)就嘗試過不單獨設(she)(she)(she)置脫(tuo)(tuo)(tuo)(tuo)(tuo)(tuo)管(guan)(guan)(guan)機(ji)(ji)(ji)(ji)(ji)(ji)(如(ru)1985年(nian)建造的(de)(de)(de)(de)(de)(de)日(ri)本(ben)NKK京濱(bin)廠的(de)(de)(de)(de)(de)(de)ф250mm機(ji)(ji)(ji)(ji)(ji)(ji)組和(he)1990年(nian)建造的(de)(de)(de)(de)(de)(de)俄(e)羅斯伏(fu)爾加鋼管(guan)(guan)(guan)廠的(de)(de)(de)(de)(de)(de)Φ426mm機(ji)(ji)(ji)(ji)(ji)(ji)組),而是(shi)將(jiang)MPM軋(ya)(ya)(ya)出(chu)(chu)的(de)(de)(de)(de)(de)(de)荒(huang)管(guan)(guan)(guan)直接送(song)人(ren)緊隨(sui)其(qi)后(hou)的(de)(de)(de)(de)(de)(de)10機(ji)(ji)(ji)(ji)(ji)(ji)架(jia)二(er)輥(gun)式(shi)脫(tuo)(tuo)(tuo)(tuo)(tuo)(tuo)管(guan)(guan)(guan)/定(ding)徑(jing)(jing)機(ji)(ji)(ji)(ji)(ji)(ji)組定(ding)徑(jing)(jing)(1997年(nian)日(ri)本(ben)住友和(he)歌山ф426mm MPM 機(ji)(ji)(ji)(ji)(ji)(ji)組脫(tuo)(tuo)(tuo)(tuo)(tuo)(tuo)管(guan)(guan)(guan)/定(ding)徑(jing)(jing)機(ji)(ji)(ji)(ji)(ji)(ji)組則是(shi)送(song)入(ru)其(qi)后(hou)的(de)(de)(de)(de)(de)(de)12架(jia)三輥(gun)式(shi)(FQS)),使脫(tuo)(tuo)(tuo)(tuo)(tuo)(tuo)管(guan)(guan)(guan)和(he)定(ding)徑(jing)(jing)在(zai)一個工序(xu)內完成;荒(huang)管(guan)(guan)(guan)在(zai)連續軋(ya)(ya)(ya)管(guan)(guan)(guan)機(ji)(ji)(ji)(ji)(ji)(ji)軋(ya)(ya)(ya)制(zhi)的(de)(de)(de)(de)(de)(de)同時(shi),被脫(tuo)(tuo)(tuo)(tuo)(tuo)(tuo)管(guan)(guan)(guan)/定(ding)徑(jing)(jing)機(ji)(ji)(ji)(ji)(ji)(ji)組從(cong)芯棒(bang)(bang)(bang)上脫(tuo)(tuo)(tuo)(tuo)(tuo)(tuo)出(chu)(chu)并完成定(ding)徑(jing)(jing)任務,實現(xian)MPM與定(ding)徑(jing)(jing)機(ji)(ji)(ji)(ji)(ji)(ji)組之間(jian)的(de)(de)(de)(de)(de)(de)連軋(ya)(ya)(ya)。但由于(yu)(yu)荒(huang)管(guan)(guan)(guan)的(de)(de)(de)(de)(de)(de)規格和(he)材質種類較多,給成品管(guan)(guan)(guan)的(de)(de)(de)(de)(de)(de)外徑(jing)(jing)控制(zhi)帶來困(kun)難,很難保證(zheng)鋼管(guan)(guan)(guan)的(de)(de)(de)(de)(de)(de)外徑(jing)(jing)精度,因此在(zai)以(yi)后(hou)的(de)(de)(de)(de)(de)(de)機(ji)(ji)(ji)(ji)(ji)(ji)組中(zhong)沒有(you)再使用(yong)這種工藝布置。為生(sheng)產(chan)(chan)薄壁(bi)(bi)管(guan)(guan)(guan)和(he)中(zhong)厚壁(bi)(bi)管(guan)(guan)(guan),每(mei)(mei)架(jia)脫(tuo)(tuo)(tuo)(tuo)(tuo)(tuo)管(guan)(guan)(guan)機(ji)(ji)(ji)(ji)(ji)(ji)的(de)(de)(de)(de)(de)(de)孔(kong)型(xing)名(ming)義(yi)直徑(jing)(jing)必(bi)須小于(yu)(yu)軋(ya)(ya)(ya)管(guan)(guan)(guan)機(ji)(ji)(ji)(ji)(ji)(ji)芯棒(bang)(bang)(bang)直徑(jing)(jing)。在(zai)生(sheng)產(chan)(chan)薄壁(bi)(bi)管(guan)(guan)(guan)時(shi),脫(tuo)(tuo)(tuo)(tuo)(tuo)(tuo)管(guan)(guan)(guan)機(ji)(ji)(ji)(ji)(ji)(ji)的(de)(de)(de)(de)(de)(de)減徑(jing)(jing)量要相應(ying)加大(da),否則薄壁(bi)(bi)管(guan)(guan)(guan)不易被脫(tuo)(tuo)(tuo)(tuo)(tuo)(tuo)出(chu)(chu)。每(mei)(mei)架(jia)脫(tuo)(tuo)(tuo)(tuo)(tuo)(tuo)管(guan)(guan)(guan)機(ji)(ji)(ji)(ji)(ji)(ji)上都裝有(you)安全白,以(yi)防止芯棒(bang)(bang)(bang)進入(ru)脫(tuo)(tuo)(tuo)(tuo)(tuo)(tuo)管(guan)(guan)(guan)機(ji)(ji)(ji)(ji)(ji)(ji)時(shi)損傷軋(ya)(ya)(ya)輥(gun)及相關(guan)的(de)(de)(de)(de)(de)(de)機(ji)(ji)(ji)(ji)(ji)(ji)械(xie)部分。在(zai)事故情況下,假如(ru)當(dang)帶芯棒(bang)(bang)(bang)的(de)(de)(de)(de)(de)(de)荒(huang)管(guan)(guan)(guan)進入(ru)脫(tuo)(tuo)(tuo)(tuo)(tuo)(tuo)管(guan)(guan)(guan)機(ji)(ji)(ji)(ji)(ji)(ji)孔(kong)型(xing)時(shi),若脫(tuo)(tuo)(tuo)(tuo)(tuo)(tuo)管(guan)(guan)(guan)機(ji)(ji)(ji)(ji)(ji)(ji)軋(ya)(ya)(ya)輥(gun)承受的(de)(de)(de)(de)(de)(de)徑(jing)(jing)向載荷(he)大(da)于(yu)(yu)預(yu)設(she)(she)(she)值,則軋(ya)(ya)(ya)輥(gun)孔(kong)型(xing)會相應(ying)張開(kai),防止芯棒(bang)(bang)(bang)頂壞軋(ya)(ya)(ya)輥(gun)及設(she)(she)(she)備。
3. 空減(jian)機的配置
空(kong)減(jian)機是空(kong)心坯減(jian)徑(jing)(jing)機的簡(jian)稱,一(yi)套連(lian)續軋(ya)管(guan)(guan)機為使其(qi)產品外(wai)徑(jing)(jing)規格范圍盡可能地大,設計時一(yi)般選用2~5個孔型(xing)(xing),軋(ya)管(guan)(guan)機后配備張減(jian)機的選擇(ze)孔型(xing)(xing)數較少(shao),軋(ya)管(guan)(guan)機后配備定徑(jing)(jing)機的選擇(ze)孔型(xing)(xing)數較多。由于孔型(xing)(xing)尺寸的變化(hua)相應(ying)地軋(ya)管(guan)(guan)機入口的毛管(guan)(guan)外(wai)徑(jing)(jing)也要隨著發生變化(hua),為適應(ying)軋(ya)管(guan)(guan)機入口毛管(guan)(guan)外(wai)徑(jing)(jing)變化(hua),通常(chang)有兩種方法:
a. 選用(yong)幾種(zhong)外徑的(de)管(guan)(guan)坯(pi),針對不同的(de)孔型選用(yong)不同規格的(de)管(guan)(guan)坯(pi),但每次更(geng)換孔型時需對穿(chuan)孔機的(de)受料槽、導衛裝置(zhi)(導板或導盤)進(jin)行更(geng)換,這樣做一方面占用(yong)較多工作(zuo)時間;另一方面管(guan)(guan)坯(pi)料場(chang)、穿(chuan)孔機工具需要場(chang)地較大;
b. 在穿(chuan)孔(kong)機(ji)與軋管(guan)機(ji)之間(jian)布置一(yi)(yi)臺空減(jian)機(ji),通(tong)過空減(jian)機(ji)可(ke)使用同(tong)一(yi)(yi)種外徑(jing)尺寸的管(guan)坯來滿足(zu)軋管(guan)機(ji)不同(tong)孔(kong)型成為可(ke)能。
浮動(dong)芯(xin)棒連續軋管(guan)(guan)機(ji)(ji)組采用(yong)(yong)穿孔(kong)機(ji)(ji)與軋管(guan)(guan)機(ji)(ji)之間(jian)布(bu)置空減機(ji)(ji)的(de)方法(fa)比較經濟,這(zhe)樣既(ji)可僅(jin)用(yong)(yong)一個(ge)規格(ge)的(de)管(guan)(guan)坯組織(zhi)生產,減少(shao)(shao)了管(guan)(guan)坯庫的(de)面(mian)積和穿孔(kong)機(ji)(ji)相關的(de)軋制工具數量,又(you)可以(yi)減少(shao)(shao)換孔(kong)型的(de)時間(jian),提高了機(ji)(ji)組的(de)作業率。經空減機(ji)(ji)后的(de)毛(mao)管(guan)(guan)在運往連續軋管(guan)(guan)機(ji)(ji)入(ru)口臺架前,先通過一個(ge)吹灰裝置用(yong)(yong)壓(ya)縮空氣吹去毛(mao)管(guan)(guan)內的(de)細小(xiao)氧化鐵皮,以(yi)減少(shao)(shao)對芯(xin)棒的(de)磨(mo)損和管(guan)(guan)子內表面(mian)缺陷,同時空減機(ji)(ji)亦消除了狄塞爾穿孔(kong)機(ji)(ji)所造成的(de)毛(mao)管(guan)(guan)頭尾(wei)外(wai)徑(jing)差,使軋制過程穩(wen)定。這(zhe)種單獨布(bu)置的(de)空減機(ji)(ji)一般使用(yong)(yong)三(san)輥式及3~6個(ge)機(ji)(ji)架。
半(ban)浮(fu)動(dong)(dong)芯棒(bang)連(lian)續(xu)軋(ya)管機(ji)(ji)(ji)組將空(kong)減(jian)機(ji)(ji)(ji)布置(zhi)(zhi)在(zai)連(lian)續(xu)軋(ya)管機(ji)(ji)(ji)的人口側,即與(yu)連(lian)續(xu)軋(ya)管機(ji)(ji)(ji)串(chuan)列布置(zhi)(zhi),一(yi)般為兩輥(gun)式、2~4架;在(zai)保(bao)持了(le)原有空(kong)減(jian)機(ji)(ji)(ji)優點的同時(shi),可縮(suo)短工藝流程(cheng),減(jian)少(shao)占地面積(ji)。這種變(bian)化一(yi)方面是因為錐形(xing)輥(gun)穿孔機(ji)(ji)(ji)的應用(yong)使(shi)變(bian)形(xing)前(qian)移,軋(ya)管機(ji)(ji)(ji)的機(ji)(ji)(ji)架數相應減(jian)少(shao)(減(jian)少(shao)2~3架),串(chuan)列布置(zhi)(zhi)因芯棒(bang)的長度增加而引起的軋(ya)制節奏變(bian)化不是很(hen)多(duo)(因軋(ya)制終了(le)芯棒(bang)向前(qian)運動(dong)(dong));另一(yi)方面串(chuan)列布置(zhi)(zhi)可減(jian)少(shao)毛管在(zai)縱(zong)向移動(dong)(dong)過程(cheng)中內表面的氧化和溫降,能更有效地確保(bao)鋼管質量(liang)。
限動(dong)芯(xin)(xin)棒(bang)連續軋(ya)(ya)管(guan)機(ji)(ji)組在(zai)最初時沒有空減機(ji)(ji),采用(yong)(yong)的(de)(de)(de)(de)(de)(de)是一種(zhong)規格的(de)(de)(de)(de)(de)(de)管(guan)坯對(dui)應一個孔(kong)型,這主要是因為軋(ya)(ya)制時芯(xin)(xin)棒(bang)與(yu)(yu)軋(ya)(ya)件內(nei)表(biao)(biao)面(mian)(mian)的(de)(de)(de)(de)(de)(de)相對(dui)運動(dong)比浮(fu)(fu)動(dong)的(de)(de)(de)(de)(de)(de)大,芯(xin)(xin)棒(bang)的(de)(de)(de)(de)(de)(de)工作條(tiao)件更為惡劣,芯(xin)(xin)棒(bang)更容易磨損和劃傷(shang)。限動(dong)芯(xin)(xin)棒(bang)工藝上不允許毛(mao)管(guan)在(zai)進入軋(ya)(ya)管(guan)機(ji)(ji)前(qian)做縱向運動(dong),必須有效的(de)(de)(de)(de)(de)(de)防止毛(mao)管(guan)內(nei)表(biao)(biao)面(mian)(mian)的(de)(de)(de)(de)(de)(de)二次氧化,才(cai)能確保(bao)鋼管(guan)的(de)(de)(de)(de)(de)(de)質(zhi)量,因此不可能像(xiang)浮(fu)(fu)動(dong)芯(xin)(xin)棒(bang)那樣在(zai)穿孔(kong)機(ji)(ji)與(yu)(yu)軋(ya)(ya)管(guan)機(ji)(ji)之間布置空減機(ji)(ji)。如(ru)采用(yong)(yong)半浮(fu)(fu)動(dong)芯(xin)(xin)棒(bang)的(de)(de)(de)(de)(de)(de)串列布置,因芯(xin)(xin)棒(bang)長(chang)度(du)的(de)(de)(de)(de)(de)(de)增加(jia)使軋(ya)(ya)制節奏更加(jia)緩慢(因軋(ya)(ya)制終了(le)芯(xin)(xin)棒(bang)向后運動(dong)),將影響機(ji)(ji)組的(de)(de)(de)(de)(de)(de)產(chan)能的(de)(de)(de)(de)(de)(de)發揮,也(ye)是不經濟的(de)(de)(de)(de)(de)(de)。近十年來,限動(dong)芯(xin)(xin)棒(bang)機(ji)(ji)組也(ye)在(zai)不斷吸收其他機(ji)(ji)組的(de)(de)(de)(de)(de)(de)長(chang)處,在(zai)軋(ya)(ya)管(guan)機(ji)(ji)入口側串列布置1架空減機(ji)(ji)(三(san)輥、四(si)輥形式(shi)均有),目(mu)的(de)(de)(de)(de)(de)(de)在(zai)于消(xiao)除毛(mao)管(guan)內(nei)表(biao)(biao)面(mian)(mian)與(yu)(yu)芯(xin)(xin)棒(bang)之間的(de)(de)(de)(de)(de)(de)間隙和毛(mao)管(guan)外(wai)徑的(de)(de)(de)(de)(de)(de)頭(tou)尾直徑偏差,使軋(ya)(ya)制更加(jia)平穩,從而提(ti)高軋(ya)(ya)輥的(de)(de)(de)(de)(de)(de)使用(yong)(yong)壽命,確保(bao)鋼管(guan)的(de)(de)(de)(de)(de)(de)幾何尺寸(cun)精度(du)和內(nei)外(wai)表(biao)(biao)面(mian)(mian)質(zhi)量。
4. 吹硼砂的工藝
限動(dong)芯棒(bang)連續軋(ya)(ya)管(guan)(guan)(guan)機(ji)組(zu)(zu)比浮動(dong)、半浮動(dong)機(ji)組(zu)(zu)多了(le)一個工(gong)序(xu)就(jiu)是(shi)在(zai)軋(ya)(ya)管(guan)(guan)(guan)機(ji)入(ru)口前向(xiang)毛管(guan)(guan)(guan)內(nei)用氮氣噴抗(kang)(kang)氧化(hua)(hua)(hua)劑,工(gong)藝目的(de)(de)是(shi)去除內(nei)表面的(de)(de)氧化(hua)(hua)(hua)鐵(tie)皮并防(fang)止二次氧化(hua)(hua)(hua)。抗(kang)(kang)氧化(hua)(hua)(hua)劑在(zai)高(gao)溫時呈熔融狀態可起到很好(hao)的(de)(de)潤滑(hua)作用,對抗(kang)(kang)氧化(hua)(hua)(hua)劑的(de)(de)成(cheng)分、顆粒尺(chi)寸、化(hua)(hua)(hua)學穩定(ding)性(xing)、物(wu)理穩定(ding)性(xing)及(ji)吹撒的(de)(de)數量、噴吹的(de)(de)壓力、時間(jian)都有嚴格(ge)的(de)(de)要(yao)求,主要(yao)是(shi)解(jie)決軋(ya)(ya)管(guan)(guan)(guan)機(ji)的(de)(de)延(yan)伸大、軋(ya)(ya)制(zhi)(zhi)時芯棒(bang)與軋(ya)(ya)件間(jian)相對運動(dong)較大、芯棒(bang)的(de)(de)工(gong)作條件更(geng)為(wei)惡劣,芯棒(bang)更(geng)容(rong)易(yi)磨損和(he)劃傷(shang)、潤滑(hua)條件不好(hao)時容(rong)易(yi)發生軋(ya)(ya)卡事故或軋(ya)(ya)制(zhi)(zhi)終(zhong)了(le)時脫(tuo)管(guan)(guan)(guan)機(ji)不能將荒管(guan)(guan)(guan)從(cong)芯棒(bang)中(zhong)順利的(de)(de)抽出等問題。