1. 桶形輥穿(chuan)孔(kong)機

  桶(tong)形(xing)二(er)輥(gun)穿(chuan)(chuan)(chuan)孔(kong)機是(shi)根據孔(kong)腔形(xing)成(cheng)(cheng)原理，利用旋(xuan)(xuan)轉(zhuan)橫(heng)鍛(duan)效應(ying)穿(chuan)(chuan)(chuan)孔(kong)。正是(shi)這(zhe)種孔(kong)腔現象造成(cheng)(cheng)了鋼管內表面(mian)的缺(que)陷，旋(xuan)(xuan)轉(zhuan)橫(heng)鍛(duan)效應(ying)又使(shi)毛管有較大(da)的周向切應(ying)力和(he)表面(mian)扭轉(zhuan)變(bian)形(xing)，因此，桶(tong)式穿(chuan)(chuan)(chuan)孔(kong)機很難滿足穿(chuan)(chuan)(chuan)軋高合金鋼的要求。

2. 錐形(xing)輥穿(chuan)孔機

  錐(zhui)形(xing)(xing)輥(gun)穿(chuan)(chuan)孔(kong)機(ji)采(cai)用較(jiao)大(da)(da)的(de)輾(zhan)軋(ya)(ya)(ya)角(jiao)(jiao)(jiao)(jiao)(jiao)和送(song)進(jin)(jin)(jin)(jin)角(jiao)(jiao)(jiao)(jiao)(jiao)進(jin)(jin)(jin)(jin)行斜軋(ya)(ya)(ya)穿(chuan)(chuan)孔(kong)，同時又極力(li)控制旋轉橫鍛(duan)效應的(de)產生(sheng)及(ji)控制毛管的(de)周(zhou)向(xiang)切應力(li)與表(biao)面(mian)扭轉變(bian)形(xing)(xing)。因此，錐(zhui)形(xing)(xing)輥(gun)穿(chuan)(chuan)孔(kong)機(ji)可(ke)以實現與擠壓機(ji)相(xiang)近的(de)金屬流(liu)動。從(cong)工藝(yi)參數(shu)方面(mian)講，錐(zhui)形(xing)(xing)輥(gun)穿(chuan)(chuan)孔(kong)機(ji)基(ji)本(ben)要點是(shi)兩個(ge)角(jiao)(jiao)(jiao)(jiao)(jiao)度(du)值(zhi)的(de)問題即輾(zhan)軋(ya)(ya)(ya)角(jiao)(jiao)(jiao)(jiao)(jiao)和送(song)進(jin)(jin)(jin)(jin)角(jiao)(jiao)(jiao)(jiao)(jiao)。前者對一(yi)個(ge)機(ji)組來講是(shi)定值(zhi)，后(hou)者根據設計可(ke)調(diao)整，若(ruo)(ruo)錐(zhui)形(xing)(xing)輥(gun)穿(chuan)(chuan)孔(kong)機(ji)采(cai)取軋(ya)(ya)(ya)輥(gun)水平布置方式，故(gu)可(ke)采(cai)用更大(da)(da)的(de)輾(zhan)軋(ya)(ya)(ya)角(jiao)(jiao)(jiao)(jiao)(jiao)β（27.6°）和相(xiang)對較(jiao)小(xiao)的(de)送(song)進(jin)(jin)(jin)(jin)角(jiao)(jiao)(jiao)(jiao)(jiao)α(6°~12°)，若(ruo)(ruo)這種軋(ya)(ya)(ya)機(ji)發(fa)(fa)展為(wei)軋(ya)(ya)(ya)輥(gun)上(shang)(shang)下布置時，這樣大(da)(da)的(de)輾(zhan)軋(ya)(ya)(ya)角(jiao)(jiao)(jiao)(jiao)(jiao)顯(xian)然(ran)不行，而且從(cong)工藝(yi)上(shang)(shang)講，一(yi)般以β+α=25°~30°作為(wei)一(yi)判定值(zhi)，故(gu)曼(man)內斯曼(man)鋼(gang)管公司在后(hou)來的(de)設計中，隨著軋(ya)(ya)(ya)輥(gun)上(shang)(shang)下布置形(xing)(xing)式的(de)進(jin)(jin)(jin)(jin)一(yi)步(bu)發(fa)(fa)展，將(jiang)β角(jiao)(jiao)(jiao)(jiao)(jiao)降為(wei)10°~15°。輾(zhan)軋(ya)(ya)(ya)角(jiao)(jiao)(jiao)(jiao)(jiao)和可(ke)調(diao)的(de)送(song)進(jin)(jin)(jin)(jin)角(jiao)(jiao)(jiao)(jiao)(jiao)的(de)各種配合，對穿(chuan)(chuan)孔(kong)過程(cheng)中所(suo)發(fa)(fa)生(sheng)的(de)切向(xiang)變(bian)形(xing)(xing)確(que)實產生(sheng)相(xiang)當大(da)(da)的(de)影(ying)響。