In this system,owing to the fact that vertical pass has the character of big groove bottom,little angle of side and short groove life,it often occurs slanting and torsion in pre-splitting which easily brings about production accident.
在这一系统中,由于立箱孔槽底大,侧壁斜度小,所以轧槽寿命短,预切孔切分时常切偏和扭转,生产事故较多。