國外穿孔機的發展概況
1.二輥穿(chuan)(chuan)孔(kong)(kong)機(ji)的發展 熱軋無縫鋼(gang)管生產中管坯的穿(chuan)(chuan)孔(kong)(kong)主要是在(zai)斜軋穿(chuan)(chuan)孔(kong)(kong)機(ji)上(shang)進行的,直至1970年,在(zai)斜軋穿(chuan)(chuan)孔(kong)(kong)機(ji)中設(she)有(you)導板的Stiefel穿(chuan)(chuan)孔(kong)(kong)機(ji)最為普遍,見(jian)圖(tu)6-31所示。它(ta)也被(bei)稱作具有(you)桶形軋輥的穿(chuan)(chuan)孔(kong)(kong)機(ji)。由于它(ta)的性(xing)能好,延伸率可達4、穿(chuan)(chuan)孔(kong)(kong)后(hou)空心坯長度可長達8m,所以,它(ta)被(bei)...