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。

  一般每(mei)架成型(xing)機裝有一對或多對成型(xing)輥，每(mei)列成型(xing)機組由(you)兩架以上(shang)的(de)成型(xing)機組線。在輥式(shi)(shi)冷彎(wan)成型(xing)過(guo)程中(zhong)只有彎(wan)曲變(bian)(bian)形。除坯料(liao)(liao)彎(wan)曲角局部(bu)有輕微減薄外(wai)(wai)，變(bian)(bian)形材料(liao)(liao)的(de)厚度在成型(xing)過(guo)程中(zhong)保持不變(bian)(bian)。這種加工方法特別適(shi)合(he)于外(wai)(wai)形縱長、批(pi)量較大的(de)高精(jing)度產品(pin)的(de)加工，此外(wai)(wai)，在輥式(shi)(shi)冷彎(wan)成型(xing)過(guo)程中(zhong)，可以很(hen)容易地將沖(chong)裁(cai)、打孔、壓印、縱彎(wan)等輔助加工引入進來。

  輥(gun)式(shi)冷(leng)彎成(cheng)型(xing)(xing)(xing)(xing)工(gong)(gong)(gong)藝(yi)可(ke)分(fen)為四種，即單張（或單件）成(cheng)型(xing)(xing)(xing)(xing)工(gong)(gong)(gong)藝(yi)、成(cheng)卷成(cheng)型(xing)(xing)(xing)(xing)工(gong)(gong)(gong)藝(yi)、連續成(cheng)型(xing)(xing)(xing)(xing)工(gong)(gong)(gong)藝(yi)和聯合加(jia)工(gong)(gong)(gong)工(gong)(gong)(gong)藝(yi)。每一種工(gong)(gong)(gong)藝(yi)都可(ke)分(fen)為3個階(jie)段(duan)，即成(cheng)型(xing)(xing)(xing)(xing)前坯料準備階(jie)段(duan)、成(cheng)型(xing)(xing)(xing)(xing)加(jia)工(gong)(gong)(gong)階(jie)段(duan)、型(xing)(xing)(xing)(xing)材(cai)精(jing)整階(jie)段(duan)。

  單張成(cheng)(cheng)(cheng)(cheng)型(xing)工(gong)(gong)(gong)藝(yi)就(jiu)是預定尺坯(pi)料的(de)(de)成(cheng)(cheng)(cheng)(cheng)型(xing)方法(fa)。這種方法(fa)在坯(pi)料成(cheng)(cheng)(cheng)(cheng)型(xing)之前(qian)將坯(pi)料切成(cheng)(cheng)(cheng)(cheng)定尺長度，然(ran)后用送料輥將坯(pi)料送進(jin)成(cheng)(cheng)(cheng)(cheng)型(xing)輥，成(cheng)(cheng)(cheng)(cheng)型(xing)后的(de)(de)型(xing)材不必經剪切即可收集(ji)入庫。采用這種成(cheng)(cheng)(cheng)(cheng)型(xing)工(gong)(gong)(gong)藝(yi)的(de)(de)成(cheng)(cheng)(cheng)(cheng)型(xing)輥的(de)(de)速度一般(ban)在15~75m/min.這種工(gong)(gong)(gong)藝(yi)主要應用于小批量、成(cheng)(cheng)(cheng)(cheng)型(xing)后型(xing)材鋸切比較困難的(de)(de)情況下。采用單張成(cheng)(cheng)(cheng)(cheng)型(xing)工(gong)(gong)(gong)藝(yi)成(cheng)(cheng)(cheng)(cheng)型(xing)機組的(de)(de)設備較簡單、工(gong)(gong)(gong)具費用少、投資低。但用這種生產(chan)工(gong)(gong)(gong)藝(yi)得(de)到的(de)(de)型(xing)材邊(bian)部縱向拉(la)伸較大，因而(er)只有利用側立輥才能得(de)到比較精確的(de)(de)產(chan)品(pin)形。

  成(cheng)(cheng)卷(juan)(juan)成(cheng)(cheng)型(xing)(xing)工(gong)藝(yi)和連續成(cheng)(cheng)型(xing)(xing)工(gong)藝(yi)基本相同，所不(bu)(bu)同的(de)是(shi)連續成(cheng)(cheng)型(xing)(xing)時前一(yi)卷(juan)(juan)帶(dai)(dai)材的(de)尾(wei)部與(yu)后一(yi)卷(juan)(juan)帶(dai)(dai)材的(de)頭(tou)部經過齊對(dui)焊(han)，使坯(pi)料(liao)帶(dai)(dai)材連續不(bu)(bu)斷地進(jin)人成(cheng)(cheng)型(xing)(xing)機進(jin)行成(cheng)(cheng)型(xing)(xing)。而成(cheng)(cheng)卷(juan)(juan)成(cheng)(cheng)型(xing)(xing)時帶(dai)(dai)卷(juan)(juan)頭(tou)尾(wei)不(bu)(bu)對(dui)焊(han)，進(jin)行單(dan)卷(juan)(juan)供料(liao)成(cheng)(cheng)型(xing)(xing)。與(yu)單(dan)張成(cheng)(cheng)型(xing)(xing)工(gong)藝(yi)相比，這兩種成(cheng)(cheng)型(xing)(xing)工(gong)藝(yi)更加高(gao)效、高(gao)產、通(tong)用。這兩種成(cheng)(cheng)型(xing)(xing)工(gong)藝(yi)的(de)主要優點是(shi)：

①. 帶卷成本低(di)、切損少，因(yin)而降低(di)了材(cai)料總成本。

②. 由于需要的成型(xing)機架數(shu)少且不(bu)需要額外(wai)的導衛(wei)裝置(zhi)，因而工具成本低(di)。

③. 可以加工形狀比單(dan)張成型工藝更(geng)復雜(za)的(de)型材。

④. 型材(cai)的頭(tou)尾部扭曲及張開度減小。

⑤. 由于操作幾乎是連續的，因而生產(chan)率得到提高(gao)。

  但這兩種成(cheng)(cheng)型(xing)(xing)工(gong)(gong)藝(yi)需要(yao)開卷機(ji)、活套器、對焊機(ji)、定尺飛鋸或飛剪等輔助設備(bei)，因而其機(ji)組設備(bei)投資較大(da)、占地較大(da)。成(cheng)(cheng)型(xing)(xing)機(ji)組的成(cheng)(cheng)型(xing)(xing)速度一般(ban)為30~90m/min.目前投產的絕(jue)大(da)多數(shu)輥式冷彎成(cheng)(cheng)型(xing)(xing)機(ji)組均是采用這兩種工(gong)(gong)藝(yi)，因此后面將以這兩種成(cheng)(cheng)型(xing)(xing)工(gong)(gong)藝(yi)為例進(jin)行重點闡述，圖5-1給出了其工(gong)(gong)藝(yi)流程示意圖。

  聯合加(jia)工工藝(yi)用于加(jia)工具(ju)有特定要(yao)求的(de)(de)冷(leng)彎(wan)(wan)型鋼(gang)，如高(gao)強(qiang)度(du)冷(leng)彎(wan)(wan)型鋼(gang)、閉口焊接冷(leng)彎(wan)(wan)型鋼(gang)、熱處理強(qiang)化冷(leng)彎(wan)(wan)型鋼(gang)、周期(qi)波紋板沖孔冷(leng)彎(wan)(wan)型鋼(gang)，涂(tu)層冷(leng)彎(wan)(wan)型鋼(gang)等(deng)。聯合加(jia)工成型機(ji)組的(de)(de)設(she)備(bei)(bei)(bei)最復雜、投資最高(gao)。根(gen)據(ju)產(chan)品的(de)(de)要(yao)求這種(zhong)機(ji)組可(ke)包括(kuo)如下設(she)備(bei)(bei)(bei)：直縫焊機(ji)、對焊機(ji)、輥式(shi)沖孔機(ji)、輥式(shi)壓印機(ji)、涂(tu)層機(ji)、熱處理設(she)備(bei)(bei)(bei)等(deng)。

 輥(gun)式(shi)冷彎(wan)(wan)(wan)成(cheng)(cheng)型(xing)(xing)(xing)是(shi)用一(yi)組成(cheng)(cheng)型(xing)(xing)(xing)輥(gun)將帶材逐(zhu)漸壓(ya)彎(wan)(wan)(wan)成(cheng)(cheng)所需的(de)(de)(de)斷面型(xing)(xing)(xing)材，現以冷彎(wan)(wan)(wan)角鋼為例(li)，圖(tu)5-2是(shi)由4個機架組成(cheng)(cheng)的(de)(de)(de)輥(gun)式(shi)冷彎(wan)(wan)(wan)成(cheng)(cheng)型(xing)(xing)(xing)機組，第(di)(di)一(yi)機架完成(cheng)(cheng)帶材的(de)(de)(de)平(ping)整和送進工作，第(di)(di)二～第(di)(di)四機架各承擔(dan)一(yi)定的(de)(de)(de)壓(ya)彎(wan)(wan)(wan)成(cheng)(cheng)型(xing)(xing)(xing)任務，使帶材通過(guo)后被彎(wan)(wan)(wan)曲壓(ya)制成(cheng)(cheng)角型(xing)(xing)(xing)材。每一(yi)對成(cheng)(cheng)型(xing)(xing)(xing)輥(gun)所分擔(dan)的(de)(de)(de)彎(wan)(wan)(wan)曲變形(xing)量，決定了該(gai)機架孔(kong)型(xing)(xing)(xing)設(she)計(ji)的(de)(de)(de)基本尺寸。不過(guo)至(zhi)今的(de)(de)(de)孔(kong)型(xing)(xing)(xing)設(she)計(ji)主(zhu)要還是(shi)依靠(kao)經驗的(de)(de)(de)積(ji)累，尚缺乏理論解析方法。