現(xian)代的立(li)式穿(chuan)(chuan)孔(kong)機上一般都配備完成以下(xia)動作(zuo)的輔助機械:(1)在加熱好坯(pi)(pi)料(liao)的內(nei)(nei)外(wai)表面上涂敷玻(bo)璃潤滑劑(ji);(2)將內(nei)(nei)外(wai)表面經(jing)潤滑的坯(pi)(pi)料(liao)從(cong)潤滑臺送至(zhi)穿(chuan)(chuan)孔(kong)筒上方的位置;(3)將坯(pi)(pi)料(liao)及(ji)剪切(qie)環(huan)送入穿(chuan)(chuan)孔(kong)筒并(bing)封閉穿(chuan)(chuan)孔(kong)筒的下(xia)方;(4)將玻(bo)璃潤滑劑(ji)施加到(dao)穿(chuan)(chuan)孔(kong)筒中坯(pi)(pi)料(liao)的上端(duan)面和中心孔(kong)內(nei)(nei);(5)冷(leng)卻鐓(dui)粗(cu)桿、鐓(dui)粗(cu)頭(tou);(6)清(qing)理、更(geng)換穿(chuan)(chuan)(擴)孔(kong)頭(tou);(7)從(cong)穿(chuan)(chuan)(擴)孔(kong)筒中頂(ding)出空心坯(pi)(pi)和剪切(qie)環(huan);(8)冷(leng)卻、清(qing)理、更(geng)換剪切(qie)環(huan);(9)冷(leng)卻、清(qing)理穿(chuan)(chuan)(擴)孔(kong)筒內(nei)(nei)襯;(10)接受空心坯(pi)(pi)料(liao),并(bing)將其傳送到(dao)輸出輥道(dao)上。
以上列舉的機械(xie)和裝置按照自動化程序依次工(gong)(gong)作,其(qi)結構和布置取決(擴)孔坯料(liao)的質量(liang)和尺寸、穿孔機的結構形式、穿孔筒的工(gong)(gong)位設(she)置及其(qi)工(gong)(gong)位數量(liang)。
德國制造的(de)10MN(1000t)立式穿孔(kong)機的(de)有關(guan)參數(shu)如下:

穿孔余料應留的高度由可能得到的穿孔力(li)的大小而定。
在穿(chuan)(chuan)(chuan)孔(kong)(kong)(kong)(kong)余料高(gao)度等于穿(chuan)(chuan)(chuan)孔(kong)(kong)(kong)(kong)頭(tou)直徑(jing)的一半(ban)以前(qian),穿(chuan)(chuan)(chuan)孔(kong)(kong)(kong)(kong)過程為(wei)等穿(chuan)(chuan)(chuan)孔(kong)(kong)(kong)(kong)力(li)進行。當確定了穿(chuan)(chuan)(chuan)孔(kong)(kong)(kong)(kong)機在使用(yong)最(zui)大(da)穿(chuan)(chuan)(chuan)孔(kong)(kong)(kong)(kong)頭(tou)時的穿(chuan)(chuan)(chuan)孔(kong)(kong)(kong)(kong)力(li)而(er)不(bu)考慮其(qi)增(zeng)長,則在使用(yong)最(zui)大(da)穿(chuan)(chuan)(chuan)孔(kong)(kong)(kong)(kong)頭(tou)時的穿(chuan)(chuan)(chuan)孔(kong)(kong)(kong)(kong)余料高(gao)度為(wei)穿(chuan)(chuan)(chuan)孔(kong)(kong)(kong)(kong)頭(tou)直徑(jing)之半(ban)。
實際上,穿孔(kong)余(yu)料高度的確定尚須考慮到穿孔(kong)頭邊角(jiao)半徑的大小,以及其材料流(liu)動錐體的影響。
4. 穿孔(kong)余料的(de)剪(jian)切力與支承缸(gang)的(de)封(feng)底(di)推力
按照剪(jian)應力理論:σ1-σ3 = 2Tmax,則(ze)穿孔余料(liao)剪(jian)切力為: Tmax=(σ1-σ3)/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。

5. 支承缸(gang)的封底推(tui)力
穿孔(kong)(kong)筒的(de)封(feng)底(di)(di)荷載,即單位壓力(li),相當于分布在底(di)(di)部面積(ji)上的(de)穿孔(kong)(kong)力(li),封(feng)底(di)(di)支(zhi)承桿(gan)的(de)直(zhi)徑(jing)和穿孔(kong)(kong)頭直(zhi)徑(jing)相等(deng)。封(feng)底(di)(di)支(zhi)承桿(gan)的(de)面積(ji)(或穿孔(kong)(kong)頭的(de)面積(ji)),占穿孔(kong)(kong)筒面積(ji)的(de)比值(zhi)見(jian)表(biao)8-27.

可見,當穿(chuan)(chuan)孔余(yu)(yu)料(liao)的(de)高度不低(di)于(yu)(yu)穿(chuan)(chuan)孔頭直徑之半時(shi),封底(di)推力(li)(li)(li)能達到穿(chuan)(chuan)孔力(li)(li)(li)的(de)50%就足(zu)夠了(le)。為了(le)充分利用(yong)穿(chuan)(chuan)孔力(li)(li)(li),并盡(jin)量減小(xiao)穿(chuan)(chuan)孔余(yu)(yu)料(liao)的(de)厚度,則作用(yong)于(yu)(yu)封底(di)支承桿(gan)上的(de)穿(chuan)(chuan)孔力(li)(li)(li)的(de)分量要增(zeng)加(jia),最大可以增(zeng)加(jia)到等于(yu)(yu)穿(chuan)(chuan)孔力(li)(li)(li)。
6. 31.5MN(3150t)擠壓車間10MN(1000t)立(li)式(shi)穿(chuan)孔機設備性能:



