現代(dai)的立式(shi)穿孔(kong)(kong)機上一般都配備完成以下動作的輔(fu)助(zhu)機械:(1)在(zai)加(jia)熱好坯(pi)料(liao)的內外(wai)表(biao)面(mian)上涂敷(fu)玻璃潤(run)滑(hua)劑;(2)將(jiang)內外(wai)表(biao)面(mian)經潤(run)滑(hua)的坯(pi)料(liao)從潤(run)滑(hua)臺送(song)(song)至(zhi)穿孔(kong)(kong)筒(tong)(tong)(tong)(tong)上方的位(wei)置;(3)將(jiang)坯(pi)料(liao)及剪切環(huan)(huan)送(song)(song)入穿孔(kong)(kong)筒(tong)(tong)(tong)(tong)并封閉穿孔(kong)(kong)筒(tong)(tong)(tong)(tong)的下方;(4)將(jiang)玻璃潤(run)滑(hua)劑施(shi)加(jia)到穿孔(kong)(kong)筒(tong)(tong)(tong)(tong)中(zhong)坯(pi)料(liao)的上端面(mian)和中(zhong)心孔(kong)(kong)內;(5)冷(leng)(leng)卻鐓粗桿、鐓粗頭;(6)清理、更(geng)換穿(擴)孔(kong)(kong)頭;(7)從穿(擴)孔(kong)(kong)筒(tong)(tong)(tong)(tong)中(zhong)頂出空(kong)心坯(pi)和剪切環(huan)(huan);(8)冷(leng)(leng)卻、清理、更(geng)換剪切環(huan)(huan);(9)冷(leng)(leng)卻、清理穿(擴)孔(kong)(kong)筒(tong)(tong)(tong)(tong)內襯;(10)接受空(kong)心坯(pi)料(liao),并將(jiang)其傳送(song)(song)到輸出輥道上。


 以上列舉的(de)機械和(he)(he)裝置(zhi)按(an)照(zhao)自動化(hua)程序依次工(gong)作,其結(jie)構和(he)(he)布置(zhi)取決(jue)(擴)孔坯(pi)料的(de)質量和(he)(he)尺寸、穿孔機的(de)結(jie)構形式(shi)、穿孔筒(tong)的(de)工(gong)位設置(zhi)及其工(gong)位數量。


德(de)國(guo)制造的(de)10MN(1000t)立式(shi)穿孔機的(de)有關參數如下:


表 25.jpg

 穿(chuan)孔(kong)余料應留的高度由可(ke)能得到的穿(chuan)孔(kong)力(li)的大小而定。


 在穿(chuan)(chuan)(chuan)孔(kong)(kong)余(yu)料高(gao)度等(deng)于穿(chuan)(chuan)(chuan)孔(kong)(kong)頭(tou)直徑(jing)的(de)一半(ban)以前,穿(chuan)(chuan)(chuan)孔(kong)(kong)過程為(wei)等(deng)穿(chuan)(chuan)(chuan)孔(kong)(kong)力進(jin)行(xing)。當確定了穿(chuan)(chuan)(chuan)孔(kong)(kong)機在使(shi)用最大(da)穿(chuan)(chuan)(chuan)孔(kong)(kong)頭(tou)時(shi)的(de)穿(chuan)(chuan)(chuan)孔(kong)(kong)力而不考慮其增(zeng)長(chang),則(ze)在使(shi)用最大(da)穿(chuan)(chuan)(chuan)孔(kong)(kong)頭(tou)時(shi)的(de)穿(chuan)(chuan)(chuan)孔(kong)(kong)余(yu)料高(gao)度為(wei)穿(chuan)(chuan)(chuan)孔(kong)(kong)頭(tou)直徑(jing)之半(ban)。


 實際上,穿孔余料(liao)高度的確(que)定尚須考慮到穿孔頭(tou)邊角半徑的大小,以(yi)及其材(cai)料(liao)流動錐(zhui)體的影響(xiang)。


4. 穿孔余料的剪切(qie)力與支承(cheng)缸的封(feng)底(di)推力


  按照剪應力理(li)論(lun):σ1-σ3 = 2Tmax,則穿(chuan)孔(kong)余料剪切力為:  Tmax=(σ13)/2      τ=0.5Kf


所采用的Kf相當于無損失鐓壓過程時的數值,但鋼坯下部和穿孔筒底部接觸,約有50~80℃的溫度損失,對于不同的材料在不同溫度下的Kf值見表8-26。


表 26.jpg



 5. 支承(cheng)缸的封底推力


  穿(chuan)孔(kong)筒的封底荷載(zai),即單位壓力(li),相當于分布在底部面(mian)積(ji)上的穿(chuan)孔(kong)力(li),封底支承桿的直徑和穿(chuan)孔(kong)頭(tou)直徑相等。封底支承桿的面(mian)積(ji)(或穿(chuan)孔(kong)頭(tou)的面(mian)積(ji)),占穿(chuan)孔(kong)筒面(mian)積(ji)的比(bi)值見表8-27.


表 27.jpg


  可見(jian),當(dang)穿(chuan)孔(kong)余料(liao)的(de)高(gao)度不低于穿(chuan)孔(kong)頭直徑之半時,封底推力(li)(li)能達(da)到穿(chuan)孔(kong)力(li)(li)的(de)50%就足夠了(le)。為了(le)充分利用穿(chuan)孔(kong)力(li)(li),并(bing)盡量(liang)減小(xiao)穿(chuan)孔(kong)余料(liao)的(de)厚度,則作(zuo)用于封底支(zhi)承桿(gan)上的(de)穿(chuan)孔(kong)力(li)(li)的(de)分量(liang)要增(zeng)加,最大(da)可以增(zeng)加到等(deng)于穿(chuan)孔(kong)力(li)(li)。


 6. 31.5MN(3150t)擠壓(ya)車(che)間10MN(1000t)立式穿孔機設(she)備(bei)性能: