波紋管輥壓成形技術

  波紋(wen)管由(you)波紋(wen)板(ban)分片彎曲(qu)(qu)連接(jie)成形,波紋(wen)板(ban)制造一般采用(yong)(yong)板(ban)料卷輥壓(ya)成形,輥壓(ya)孔(kong)型系(xi)統(tong)(tong)有(you)連續(xu)成形系(xi)統(tong)(tong)和(he)(he)專(zhuan)用(yong)(yong)孔(kong)型系(xi)統(tong)(tong)。目前生產波紋(wen)板(ban)應用(yong)(yong)最廣(guang)泛的(de)是連續(xu)成形系(xi)統(tong)(tong),即首先彎中心波,然(ran)后彎相(xiang)鄰波,最后彎邊波,該(gai)孔(kong)型系(xi)統(tong)(tong)的(de)優點(dian)為(wei)輥耗最低,其(qi)缺點(dian)為(wei)工件易出現(xian)橫(heng)向(xiang)彎曲(qu)(qu)和(he)(he)扭曲(qu)(qu)。專(zhuan)用(yong)(yong)孔(kong)型系(xi)統(tong)(tong)主要(yao)用(yong)(yong)于生產波紋(wen)板(ban),在開(kai)始階段(duan)先預(yu)彎出弧形波,再將其(qi)鐓壓(ya)成形,該(gai)方法保證各(ge)彎角處金(jin)屬減薄最輕。其(qi)缺點(dian)為(wei)輥耗高,對成形設備和(he)(he)材料要(yao)求高。

  根據多年的研(yan)究和產(chan)品開發經驗,將上述兩(liang)種孔型系統進行了(le)整合(he),充(chong)分吸(xi)取了(le)兩(liang)種成(cheng)形方(fang)法的優點,克(ke)服了(le)成(cheng)形過程中經常出現(xian)的橫(heng)向彎曲、扭曲和邊波(bo)等缺(que)陷(xian),經試驗驗證,該成(cheng)形系統能很好地(di)實(shi)現(xian)寬幅(fu)板類產(chan)品輥壓成(cheng)形。

  在輥彎過程中常(chang)常(chang)遇到一些問題,如袋形波、邊波、劃痕、翹(qiao)曲、裂紋、回(hui)彈、斷面形狀畸變(bian)等。針對(dui)上述缺(que)陷(xian)的產生(sheng),利用有限元模(mo)擬研究了(le)(le)波紋板類產品輥壓變(bian)形過程,計算了(le)(le)角部節點輥壓應變(bian)分布,分析(xi)了(le)(le)缺(que)陷(xian)產生(sheng)的原因和(he)解決(jue)辦法。

  板(ban)材(cai)橫向即(ji)寬度方向在(zai)(zai)(zai)彎(wan)曲角部位附近(jin),應(ying)變(bian)(bian)(bian)變(bian)(bian)(bian)化大,并有(you)明顯的峰(feng)值,而(er)在(zai)(zai)(zai)底部部位應(ying)力(li)均(jun)勻(yun)分(fen)布,因此應(ying)變(bian)(bian)(bian)主要集中在(zai)(zai)(zai)彎(wan)曲角附近(jin)的變(bian)(bian)(bian)形(xing)(xing)(xing)(xing)區域。板(ban)材(cai)的縱(zong)向變(bian)(bian)(bian)形(xing)(xing)(xing)(xing)主要集中在(zai)(zai)(zai)變(bian)(bian)(bian)形(xing)(xing)(xing)(xing)區和變(bian)(bian)(bian)形(xing)(xing)(xing)(xing)過(guo)渡區,反映在(zai)(zai)(zai)彎(wan)曲部位,變(bian)(bian)(bian)形(xing)(xing)(xing)(xing)量(liang)較大,但處于彈性變(bian)(bian)(bian)形(xing)(xing)(xing)(xing)范圍,即(ji)板(ban)材(cai)在(zai)(zai)(zai)縱(zong)向上存(cun)(cun)在(zai)(zai)(zai)彈性拉伸變(bian)(bian)(bian)形(xing)(xing)(xing)(xing),該應(ying)變(bian)(bian)(bian)的存(cun)(cun)在(zai)(zai)(zai),將引起型材(cai)縱(zong)向彎(wan)曲和斷(duan)面形(xing)(xing)(xing)(xing)狀畸變(bian)(bian)(bian)。

  總的(de)來說,橫向(xiang)應變(bian)要(yao)(yao)大于縱向(xiang)應變(bian),說明(ming)變(bian)形(xing)主(zhu)要(yao)(yao)發生在橫向(xiang)即板(ban)材(cai)的(de)寬(kuan)度方向(xiang),在冷(leng)彎(wan)成形(xing)中(zhong),摩擦(ca)是重要(yao)(yao)的(de)影(ying)響因素(su),利用(yong)有限元模擬(ni)了(le)摩擦(ca)系數(shu)對(dui)冷(leng)彎(wan)成形(xing)的(de)影(ying)響。如當(dang)摩擦(ca)系數(shu)為0.2時(shi),在冷(leng)彎(wan)過程(cheng)中(zhong)出(chu)現(xian)粘輥的(de)現(xian)象,把摩擦(ca)系數(shu)調整為0.1后,板(ban)材(cai)被冷(leng)彎(wan)后就沒有異常的(de)粘輥和網格畸變(bian)的(de)現(xian)象。從上述分析可以看出(chu),輥型表面(mian)狀態對(dui)工件的(de)扭(niu)曲具有較大的(de)影(ying)響。