這種(zhong)軋機亦稱皮(pi)爾格(ge)軋管(guan)機,1891年(nian)由曼乃斯曼兄(xiong)弟發明(ming),1900年(nian)將(jiang)芯棒設計成移動式為止(zhi)才(cai)達到完全機械化,成為目前狀態,其(qi)操作過程如圖4-21所示。
此軋(ya)(ya)(ya)機(ji)操(cao)(cao)作(zuo)的(de)(de)(de)基本特點(dian)是鍛軋(ya)(ya)(ya),軋(ya)(ya)(ya)輥旋轉方(fang)向(xiang)與軋(ya)(ya)(ya)件送進(jin)方(fang)向(xiang)相反(fan),軋(ya)(ya)(ya)輥孔(kong)型沿圓周(zhou)為(wei)變(bian)斷面,軋(ya)(ya)(ya)制(zhi)時(shi)軋(ya)(ya)(ya)件反(fan)送進(jin)方(fang)向(xiang)運行。送料由做往(wang)(wang)復運動(dong)的(de)(de)(de)芯(xin)棒(bang)送進(jin)機(ji)構完成,這種軋(ya)(ya)(ya)制(zhi)形(xing)式的(de)(de)(de)延伸系數為(wei)7~15,可用(yong)鋼(gang)錠直接生(sheng)產(chan)(chan)。目前(qian)主(zhu)(zhu)要用(yong)于生(sheng)產(chan)(chan)大(da)直徑(jing)中、厚壁管、異形(xing)管,利用(yong)鍛軋(ya)(ya)(ya)的(de)(de)(de)特點(dian)還可生(sheng)產(chan)(chan)合金鋼(gang)管。生(sheng)產(chan)(chan)的(de)(de)(de)規(gui)格(ge)范(fan)圍(wei)外徑(jing)為(wei)114~665mm;壁厚2.5~100mm;軋(ya)(ya)(ya)后長度(du)可達40m.該(gai)軋(ya)(ya)(ya)機(ji)的(de)(de)(de)主(zhu)(zhu)要缺點(dian)是:效率低(di),輔助操(cao)(cao)作(zuo)時(shi)間占整個(ge)周(zhou)期的(de)(de)(de)25%;孔(kong)型不易加工;芯(xin)棒(bang)長,生(sheng)產(chan)(chan)規(gui)格(ge)范(fan)圍(wei)窄,壁厚精度(du)低(di)。為(wei)減少周(zhou)期,軋(ya)(ya)(ya)機(ji)皆采用(yong)線外插芯(xin)棒(bang)鍛頭(tou),再送往(wang)(wang)主(zhu)(zhu)機(ji)軋(ya)(ya)(ya)制(zhi),以(yi)減少輔助操(cao)(cao)作(zuo)時(shi)間。為(wei)改(gai)善周(zhou)期軋(ya)(ya)(ya)機(ji)加工的(de)(de)(de)規(gui)格(ge)尺寸窄的(de)(de)(de)問題,有的(de)(de)(de)配以(yi)張力減徑(jing)來(lai)擴大(da)機(ji)組生(sheng)產(chan)(chan)規(gui)格(ge)范(fan)圍(wei)。