輥式冷彎成型是以金屬薄板或帶卷為原料，并通過多架裝配了具有一定形狀的成型輥對坯料逐架次進行彎曲變形，從而得到均一最面的產品的塑性加工方法。

  一(yi)般每(mei)架成型機(ji)裝(zhuang)有一(yi)對或多對成型輥，每(mei)列(lie)成型機(ji)組(zu)由兩架以(yi)上的成型機(ji)組(zu)線(xian)。在輥式(shi)冷彎(wan)成型過(guo)程(cheng)中只(zhi)有彎(wan)曲變(bian)形。除(chu)坯料彎(wan)曲角局(ju)部有輕微減薄外(wai)(wai)(wai)，變(bian)形材料的厚(hou)度在成型過(guo)程(cheng)中保持不變(bian)。這(zhe)種加(jia)工(gong)方法特別適合于(yu)外(wai)(wai)(wai)形縱(zong)長、批量較大的高(gao)精度產品的加(jia)工(gong)，此外(wai)(wai)(wai)，在輥式(shi)冷彎(wan)成型過(guo)程(cheng)中，可以(yi)很容易地將沖裁、打孔、壓印、縱(zong)彎(wan)等輔助(zhu)加(jia)工(gong)引入進來。

  輥(gun)式冷彎成(cheng)型(xing)工(gong)(gong)藝可(ke)分(fen)為(wei)四(si)種，即單(dan)張（或單(dan)件）成(cheng)型(xing)工(gong)(gong)藝、成(cheng)卷成(cheng)型(xing)工(gong)(gong)藝、連續(xu)成(cheng)型(xing)工(gong)(gong)藝和聯合(he)加工(gong)(gong)工(gong)(gong)藝。每一種工(gong)(gong)藝都可(ke)分(fen)為(wei)3個階(jie)段(duan)，即成(cheng)型(xing)前坯料準備(bei)階(jie)段(duan)、成(cheng)型(xing)加工(gong)(gong)階(jie)段(duan)、型(xing)材精(jing)整階(jie)段(duan)。

  單(dan)(dan)張成(cheng)型(xing)工藝(yi)(yi)就是(shi)預定(ding)尺坯料(liao)的成(cheng)型(xing)方法。這種(zhong)方法在坯料(liao)成(cheng)型(xing)之前將(jiang)坯料(liao)切(qie)(qie)成(cheng)定(ding)尺長度(du)，然后用(yong)(yong)(yong)送(song)(song)料(liao)輥(gun)將(jiang)坯料(liao)送(song)(song)進成(cheng)型(xing)輥(gun)，成(cheng)型(xing)后的型(xing)材(cai)不必經剪切(qie)(qie)即可收(shou)集(ji)入庫。采用(yong)(yong)(yong)這種(zhong)成(cheng)型(xing)工藝(yi)(yi)的成(cheng)型(xing)輥(gun)的速度(du)一般在15~75m/min.這種(zhong)工藝(yi)(yi)主要應用(yong)(yong)(yong)于小批(pi)量、成(cheng)型(xing)后型(xing)材(cai)鋸切(qie)(qie)比(bi)較困難的情況下。采用(yong)(yong)(yong)單(dan)(dan)張成(cheng)型(xing)工藝(yi)(yi)成(cheng)型(xing)機組(zu)的設備較簡單(dan)(dan)、工具費用(yong)(yong)(yong)少、投資低。但用(yong)(yong)(yong)這種(zhong)生(sheng)產工藝(yi)(yi)得(de)到的型(xing)材(cai)邊部縱向拉伸較大(da)，因而只有利用(yong)(yong)(yong)側立(li)輥(gun)才(cai)能得(de)到比(bi)較精確的產品(pin)形。

  成(cheng)(cheng)(cheng)(cheng)卷(juan)成(cheng)(cheng)(cheng)(cheng)型(xing)工(gong)藝(yi)和連續(xu)成(cheng)(cheng)(cheng)(cheng)型(xing)工(gong)藝(yi)基本相同，所不同的(de)(de)是(shi)連續(xu)成(cheng)(cheng)(cheng)(cheng)型(xing)時前一(yi)(yi)卷(juan)帶(dai)(dai)材(cai)的(de)(de)尾部(bu)與后一(yi)(yi)卷(juan)帶(dai)(dai)材(cai)的(de)(de)頭(tou)部(bu)經過齊對焊，使坯料帶(dai)(dai)材(cai)連續(xu)不斷地(di)進(jin)人成(cheng)(cheng)(cheng)(cheng)型(xing)機進(jin)行(xing)成(cheng)(cheng)(cheng)(cheng)型(xing)。而成(cheng)(cheng)(cheng)(cheng)卷(juan)成(cheng)(cheng)(cheng)(cheng)型(xing)時帶(dai)(dai)卷(juan)頭(tou)尾不對焊，進(jin)行(xing)單(dan)卷(juan)供(gong)料成(cheng)(cheng)(cheng)(cheng)型(xing)。與單(dan)張成(cheng)(cheng)(cheng)(cheng)型(xing)工(gong)藝(yi)相比，這兩種成(cheng)(cheng)(cheng)(cheng)型(xing)工(gong)藝(yi)更加高(gao)效、高(gao)產(chan)、通(tong)用。這兩種成(cheng)(cheng)(cheng)(cheng)型(xing)工(gong)藝(yi)的(de)(de)主要優點是(shi)：

①. 帶(dai)卷(juan)成本低、切損少，因而降低了材料總成本。

②. 由于(yu)需要(yao)的成(cheng)型機架數少(shao)且不需要(yao)額外的導衛裝置，因而工(gong)具(ju)成(cheng)本低。

③. 可(ke)以(yi)加工形狀(zhuang)比單張成型工藝(yi)更復雜(za)的型材(cai)。

④. 型材的頭尾部扭曲(qu)及張開度減小。

⑤. 由(you)于操作幾乎是連續的，因而(er)生產率得到(dao)提高。

  但這兩(liang)(liang)種(zhong)成型工藝需(xu)要開卷機、活套器(qi)、對(dui)焊機、定尺(chi)飛鋸或飛剪等輔助設備(bei)，因(yin)而其機組(zu)設備(bei)投資較(jiao)大、占地較(jiao)大。成型機組(zu)的(de)(de)成型速度一(yi)般為(wei)30~90m/min.目(mu)前投產的(de)(de)絕大多(duo)數輥式(shi)冷彎成型機組(zu)均是采(cai)用(yong)這兩(liang)(liang)種(zhong)工藝，因(yin)此后面(mian)將以這兩(liang)(liang)種(zhong)成型工藝為(wei)例進(jin)行重點闡(chan)述，圖5-1給出了其工藝流(liu)程(cheng)示意圖。

  聯(lian)合(he)加(jia)(jia)工(gong)工(gong)藝用于加(jia)(jia)工(gong)具有(you)特定要(yao)求的(de)冷(leng)彎(wan)(wan)型(xing)鋼，如(ru)高強度(du)冷(leng)彎(wan)(wan)型(xing)鋼、閉口焊(han)接(jie)冷(leng)彎(wan)(wan)型(xing)鋼、熱處(chu)理強化冷(leng)彎(wan)(wan)型(xing)鋼、周期(qi)波紋板(ban)沖孔(kong)冷(leng)彎(wan)(wan)型(xing)鋼，涂層冷(leng)彎(wan)(wan)型(xing)鋼等。聯(lian)合(he)加(jia)(jia)工(gong)成型(xing)機(ji)組的(de)設備(bei)最(zui)復(fu)雜(za)、投資最(zui)高。根(gen)據產品的(de)要(yao)求這種(zhong)機(ji)組可包括如(ru)下設備(bei)：直縫焊(han)機(ji)、對焊(han)機(ji)、輥式沖孔(kong)機(ji)、輥式壓印機(ji)、涂層機(ji)、熱處(chu)理設備(bei)等。

 輥式冷(leng)彎成(cheng)(cheng)(cheng)型(xing)(xing)是(shi)用一(yi)組成(cheng)(cheng)(cheng)型(xing)(xing)輥將(jiang)帶材逐漸壓彎成(cheng)(cheng)(cheng)所(suo)(suo)需的(de)(de)斷(duan)面型(xing)(xing)材，現以冷(leng)彎角(jiao)(jiao)鋼為例，圖5-2是(shi)由4個機(ji)(ji)架(jia)(jia)組成(cheng)(cheng)(cheng)的(de)(de)輥式冷(leng)彎成(cheng)(cheng)(cheng)型(xing)(xing)機(ji)(ji)組，第(di)一(yi)機(ji)(ji)架(jia)(jia)完(wan)成(cheng)(cheng)(cheng)帶材的(de)(de)平整和(he)送進工作(zuo)，第(di)二～第(di)四機(ji)(ji)架(jia)(jia)各(ge)承擔一(yi)定(ding)的(de)(de)壓彎成(cheng)(cheng)(cheng)型(xing)(xing)任務，使帶材通(tong)過(guo)后被彎曲壓制成(cheng)(cheng)(cheng)角(jiao)(jiao)型(xing)(xing)材。每一(yi)對成(cheng)(cheng)(cheng)型(xing)(xing)輥所(suo)(suo)分擔的(de)(de)彎曲變(bian)形量，決定(ding)了該機(ji)(ji)架(jia)(jia)孔型(xing)(xing)設計(ji)的(de)(de)基本尺寸。不過(guo)至今的(de)(de)孔型(xing)(xing)設計(ji)主要(yao)還是(shi)依靠經驗的(de)(de)積累(lei)，尚缺乏(fa)理論解(jie)析方法。