這(zhe)種(zhong)軋機(ji)亦稱皮爾格軋管機(ji),1891年由曼(man)乃斯曼(man)兄弟(di)發明,1900年將芯棒(bang)設計(ji)成移動(dong)式(shi)為(wei)止才達到完(wan)全機(ji)械化,成為(wei)目前狀態,其操作過程如(ru)圖4-21所示。


圖 21.jpg



  此軋(ya)機(ji)操(cao)作(zuo)的基本(ben)特(te)點(dian)是鍛軋(ya),軋(ya)輥旋轉方向與(yu)軋(ya)件送(song)(song)進(jin)方向相反(fan),軋(ya)輥孔(kong)(kong)型(xing)沿圓周(zhou)為(wei)變(bian)斷(duan)面,軋(ya)制時軋(ya)件反(fan)送(song)(song)進(jin)方向運(yun)(yun)行。送(song)(song)料(liao)由做(zuo)往(wang)復運(yun)(yun)動的芯(xin)棒送(song)(song)進(jin)機(ji)構完成,這種軋(ya)制形式的延(yan)伸系數為(wei)7~15,可用鋼錠直接生(sheng)(sheng)(sheng)產(chan)(chan)。目(mu)前主(zhu)要用于生(sheng)(sheng)(sheng)產(chan)(chan)大直徑(jing)中、厚壁管(guan)、異形管(guan),利(li)用鍛軋(ya)的特(te)點(dian)還可生(sheng)(sheng)(sheng)產(chan)(chan)合金(jin)鋼管(guan)。生(sheng)(sheng)(sheng)產(chan)(chan)的規(gui)(gui)格(ge)范圍外徑(jing)為(wei)114~665mm;壁厚2.5~100mm;軋(ya)后長度可達(da)40m.該軋(ya)機(ji)的主(zhu)要缺點(dian)是:效率低(di),輔助(zhu)操(cao)作(zuo)時間(jian)占整個周(zhou)期的25%;孔(kong)(kong)型(xing)不易加工;芯(xin)棒長,生(sheng)(sheng)(sheng)產(chan)(chan)規(gui)(gui)格(ge)范圍窄,壁厚精度低(di)。為(wei)減少(shao)周(zhou)期,軋(ya)機(ji)皆(jie)采用線外插芯(xin)棒鍛頭,再送(song)(song)往(wang)主(zhu)機(ji)軋(ya)制,以減少(shao)輔助(zhu)操(cao)作(zuo)時間(jian)。為(wei)改善周(zhou)期軋(ya)機(ji)加工的規(gui)(gui)格(ge)尺寸窄的問題,有的配以張(zhang)力減徑(jing)來擴大機(ji)組生(sheng)(sheng)(sheng)產(chan)(chan)規(gui)(gui)格(ge)范圍。