保持工作輥的上輥和下輥相對于軋機中心線對稱且在軸線方向上移動。這種的工作輥移動的設計，是用來改變工作輥和支撐輥的偏移需要大的移動量。這種大移動量的采用需要大量的改裝費用，并且需要解決很多問題.

The upper and lower rolls of the work roll are symmetrical and move in the direction of the axis of the rolling mill. The movement of this work roll is designed to change the shift of work rolls and support rolls to require large amounts of movement. The use of this large shift of momentum requires a lot of modification costs, and many problems need to be solved.

半閉口式機架是機架與機架蓋之間采用斜楔連接的一種機架。這種機架兼有開口式機架和閉口式機架的優(yōu)點，裝卸、換輥方便，制造容易，并有較高的剛度，故一般大中型的型鋼軋機都采用這種形式的機架。

A semi closed frame is a frame with a wedge between the frame and the frame cover. The rack has the advantages of open frame and closed frame. It has the advantages of loading and unloading, easy roll changing, easy manufacture and high rigidity. Therefore, a large and medium-sized steel mill is adopted in this form.

四棍軋機的工作輥直徑較小，傳遞軋制力矩，軋延壓力由直徑較大的支承輥承受。這類設備的主要優(yōu)點是相對剛度較大，壓下量大、軋延力小，可軋制較薄的板材，也包括有可逆和連軋兩種。

The working roll diameter of the four bar mill is small, and the rolling torque is transferred. The rolling pressure is borne by the backup roller with larger diameter. The main advantages of this type of equipment are relatively large stiffness, large reduction, low rolling force, thin rolled sheets, and reversible and continuous rolling two.