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。
一般每架成(cheng)型機(ji)(ji)裝有一對或(huo)多對成(cheng)型輥(gun)(gun)，每列成(cheng)型機(ji)(ji)組(zu)由(you)兩(liang)架以(yi)上的(de)(de)成(cheng)型機(ji)(ji)組(zu)線(xian)。在輥(gun)(gun)式(shi)(shi)冷彎(wan)成(cheng)型過程中(zhong)(zhong)只有彎(wan)曲(qu)變形(xing)。除坯料彎(wan)曲(qu)角局部有輕微減薄外，變形(xing)材料的(de)(de)厚(hou)度在成(cheng)型過程中(zhong)(zhong)保持不變。這(zhe)種加(jia)工(gong)方法特別適合于外形(xing)縱長、批量較大的(de)(de)高精度產品的(de)(de)加(jia)工(gong)，此外，在輥(gun)(gun)式(shi)(shi)冷彎(wan)成(cheng)型過程中(zhong)(zhong)，可以(yi)很(hen)容易地(di)將沖裁、打孔、壓印、縱彎(wan)等輔(fu)助加(jia)工(gong)引(yin)入進(jin)來(lai)。
輥式(shi)冷彎成(cheng)型(xing)工(gong)(gong)(gong)(gong)(gong)藝可(ke)分為四種(zhong)，即單張（或單件）成(cheng)型(xing)工(gong)(gong)(gong)(gong)(gong)藝、成(cheng)卷(juan)成(cheng)型(xing)工(gong)(gong)(gong)(gong)(gong)藝、連續成(cheng)型(xing)工(gong)(gong)(gong)(gong)(gong)藝和聯合加工(gong)(gong)(gong)(gong)(gong)工(gong)(gong)(gong)(gong)(gong)藝。每一種(zhong)工(gong)(gong)(gong)(gong)(gong)藝都可(ke)分為3個階段(duan)，即成(cheng)型(xing)前坯料準備階段(duan)、成(cheng)型(xing)加工(gong)(gong)(gong)(gong)(gong)階段(duan)、型(xing)材(cai)精整階段(duan)。
單(dan)張成(cheng)(cheng)(cheng)(cheng)(cheng)型(xing)(xing)工(gong)(gong)藝(yi)就是(shi)預定尺(chi)坯料(liao)(liao)的(de)成(cheng)(cheng)(cheng)(cheng)(cheng)型(xing)(xing)方法(fa)。這(zhe)(zhe)種(zhong)方法(fa)在坯料(liao)(liao)成(cheng)(cheng)(cheng)(cheng)(cheng)型(xing)(xing)之(zhi)前將坯料(liao)(liao)切成(cheng)(cheng)(cheng)(cheng)(cheng)定尺(chi)長度，然后用(yong)送料(liao)(liao)輥將坯料(liao)(liao)送進成(cheng)(cheng)(cheng)(cheng)(cheng)型(xing)(xing)輥，成(cheng)(cheng)(cheng)(cheng)(cheng)型(xing)(xing)后的(de)型(xing)(xing)材不必(bi)經(jing)剪切即可(ke)收(shou)集入(ru)庫(ku)。采用(yong)這(zhe)(zhe)種(zhong)成(cheng)(cheng)(cheng)(cheng)(cheng)型(xing)(xing)工(gong)(gong)藝(yi)的(de)成(cheng)(cheng)(cheng)(cheng)(cheng)型(xing)(xing)輥的(de)速度一般在15~75m/min.這(zhe)(zhe)種(zhong)工(gong)(gong)藝(yi)主要應用(yong)于(yu)小(xiao)批量、成(cheng)(cheng)(cheng)(cheng)(cheng)型(xing)(xing)后型(xing)(xing)材鋸切比較困難的(de)情況下。采用(yong)單(dan)張成(cheng)(cheng)(cheng)(cheng)(cheng)型(xing)(xing)工(gong)(gong)藝(yi)成(cheng)(cheng)(cheng)(cheng)(cheng)型(xing)(xing)機組的(de)設備較簡單(dan)、工(gong)(gong)具(ju)費用(yong)少、投資低(di)。但用(yong)這(zhe)(zhe)種(zhong)生產工(gong)(gong)藝(yi)得(de)到的(de)型(xing)(xing)材邊部縱向拉伸較大，因而只有利用(yong)側立(li)輥才能(neng)得(de)到比較精確的(de)產品形(xing)。
成(cheng)(cheng)卷成(cheng)(cheng)型(xing)(xing)工(gong)(gong)藝和連(lian)(lian)續(xu)成(cheng)(cheng)型(xing)(xing)工(gong)(gong)藝基本相(xiang)同(tong)，所不同(tong)的(de)是連(lian)(lian)續(xu)成(cheng)(cheng)型(xing)(xing)時前一(yi)卷帶(dai)(dai)(dai)材的(de)尾部與后一(yi)卷帶(dai)(dai)(dai)材的(de)頭部經過齊對焊(han)，使坯料帶(dai)(dai)(dai)材連(lian)(lian)續(xu)不斷地進(jin)人成(cheng)(cheng)型(xing)(xing)機進(jin)行(xing)成(cheng)(cheng)型(xing)(xing)。而成(cheng)(cheng)卷成(cheng)(cheng)型(xing)(xing)時帶(dai)(dai)(dai)卷頭尾不對焊(han)，進(jin)行(xing)單卷供(gong)料成(cheng)(cheng)型(xing)(xing)。與單張(zhang)成(cheng)(cheng)型(xing)(xing)工(gong)(gong)藝相(xiang)比(bi)，這兩種成(cheng)(cheng)型(xing)(xing)工(gong)(gong)藝更加高效、高產(chan)、通(tong)用。這兩種成(cheng)(cheng)型(xing)(xing)工(gong)(gong)藝的(de)主要優(you)點(dian)是：
①. 帶卷成本低(di)(di)、切損少，因而降低(di)(di)了材料總成本。
②. 由于需要(yao)(yao)的(de)成型機(ji)架數(shu)少且不需要(yao)(yao)額(e)外(wai)的(de)導衛裝置，因而工具成本低。
③. 可以(yi)加(jia)工(gong)(gong)形(xing)狀比單張成型工(gong)(gong)藝(yi)更(geng)復(fu)雜的(de)型材。
④. 型材的(de)頭尾部扭(niu)曲(qu)及張開度(du)減(jian)小。
⑤. 由于操(cao)作幾乎是連續的，因(yin)而生產率得到提高。
但這(zhe)兩種(zhong)(zhong)成型(xing)(xing)工(gong)(gong)藝(yi)(yi)需要開(kai)卷(juan)機(ji)、活套器、對焊(han)機(ji)、定尺飛(fei)鋸或飛(fei)剪等輔助設(she)備(bei)(bei)，因(yin)而其機(ji)組設(she)備(bei)(bei)投資較(jiao)大、占(zhan)地較(jiao)大。成型(xing)(xing)機(ji)組的成型(xing)(xing)速度一般為30~90m/min.目前投產的絕大多數輥式冷彎成型(xing)(xing)機(ji)組均是(shi)采用這(zhe)兩種(zhong)(zhong)工(gong)(gong)藝(yi)(yi)，因(yin)此后面將以這(zhe)兩種(zhong)(zhong)成型(xing)(xing)工(gong)(gong)藝(yi)(yi)為例進行重(zhong)點闡(chan)述，圖5-1給(gei)出了(le)其工(gong)(gong)藝(yi)(yi)流(liu)程示(shi)意圖。
聯合加工工藝用于加工具(ju)有特定要求(qiu)的冷(leng)(leng)(leng)彎(wan)(wan)型(xing)(xing)(xing)鋼(gang)(gang)(gang)，如高強(qiang)度冷(leng)(leng)(leng)彎(wan)(wan)型(xing)(xing)(xing)鋼(gang)(gang)(gang)、閉(bi)口焊接冷(leng)(leng)(leng)彎(wan)(wan)型(xing)(xing)(xing)鋼(gang)(gang)(gang)、熱處理強(qiang)化冷(leng)(leng)(leng)彎(wan)(wan)型(xing)(xing)(xing)鋼(gang)(gang)(gang)、周期波(bo)紋板沖孔冷(leng)(leng)(leng)彎(wan)(wan)型(xing)(xing)(xing)鋼(gang)(gang)(gang)，涂(tu)層冷(leng)(leng)(leng)彎(wan)(wan)型(xing)(xing)(xing)鋼(gang)(gang)(gang)等(deng)。聯合加工成型(xing)(xing)(xing)機(ji)組的設(she)備(bei)(bei)最復雜、投資最高。根據產(chan)品的要求(qiu)這種機(ji)組可包括如下設(she)備(bei)(bei)：直縫焊機(ji)、對焊機(ji)、輥(gun)式沖孔機(ji)、輥(gun)式壓印機(ji)、涂(tu)層機(ji)、熱處理設(she)備(bei)(bei)等(deng)。
輥(gun)(gun)式冷彎(wan)(wan)(wan)(wan)成(cheng)型是(shi)用一(yi)(yi)組成(cheng)型輥(gun)(gun)將帶(dai)(dai)材逐漸壓(ya)彎(wan)(wan)(wan)(wan)成(cheng)所需的(de)斷面型材，現以冷彎(wan)(wan)(wan)(wan)角(jiao)鋼為(wei)例(li)，圖5-2是(shi)由4個機(ji)架組成(cheng)的(de)輥(gun)(gun)式冷彎(wan)(wan)(wan)(wan)成(cheng)型機(ji)組，第一(yi)(yi)機(ji)架完成(cheng)帶(dai)(dai)材的(de)平整(zheng)和送進工作，第二～第四機(ji)架各承(cheng)擔(dan)一(yi)(yi)定的(de)壓(ya)彎(wan)(wan)(wan)(wan)成(cheng)型任務(wu)，使帶(dai)(dai)材通過(guo)后被彎(wan)(wan)(wan)(wan)曲(qu)壓(ya)制成(cheng)角(jiao)型材。每一(yi)(yi)對(dui)成(cheng)型輥(gun)(gun)所分擔(dan)的(de)彎(wan)(wan)(wan)(wan)曲(qu)變形(xing)量，決定了(le)該(gai)機(ji)架孔型設(she)計的(de)基本尺寸。不過(guo)至今(jin)的(de)孔型設(she)計主要還是(shi)依靠經驗的(de)積累，尚缺乏理(li)論(lun)解析方法。
