开口式机架由机架底座和上横梁组成。
开口式机架是型钢车间常见的一种机架形式。这种机架的优点是制造简单，装卸、换辊方便。其缺点是强度和刚度较低，轧辊辊跳值较大，影响产品精度，故只适用于大型轧机。
The open frame is of the frame base and the upper cross beam.
The open frame is one of the most common forms in the steel workshop. The advantages of this frame are simple manufacturing, loading and unloading, and convenient for roll change. Its disadvantage is that its strength and stiffness are low, the roll roll value is larger and the precision of the product is affected, so it is only suitable for large rolling mill.
半闭口式机架是机架与机架盖之间采用斜楔连接的一种机架。这种机架兼有开口式机架和闭口式机架的优点，装卸、换辊方便，制造容易，并有较高的刚度，故一般大中型的型钢轧机都采用这种形式的机架。
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.
四棍轧机的工作辊直径较小，传递轧制力矩，轧延压力由直径较大的支承辊承受。这类设备的主要优点是相对刚度较大，压下量大、轧延力小，可轧制较薄的板材，也包括有可逆和连轧两种。
The working roll diameter of the four bar mill is ***all, 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.
还有三辊轧机，轧机***厂家介绍，这种轧机由于本身的优势并不突出，所以使用的比较少。那么，四辊轧机具有怎样的特点恩？这种类型的轧机的工作辊直径较小，传递轧制力矩，轧延压力由直径较大的支承辊承受。其的优点在于相对刚度高、压下量大、轧延力小，比较适合轧制较薄的板材。当厚度偏差增大（在板宽方向上厚度不同）导致在材料设计后产品损失中应考虑增加板厚边缘。
There are three-high mill, mill professional manufacturers , this kind of mill because of its advantages are not prominent, so the use of less. So, what are the characteristics of the four high rolling mill?驱动电机斜置在锯机底座上，通过伞齿轮及主传动轴带动锯片，锯片由液压装置锁紧在传动轴上。 The working roll diameter of this type of mill is ***aller, the rolling torque is tran***itted, and the rolling pressure is borne by the backup roll with larger diameter. Its advantages are high relative stiffness, large reduction and ***all rolling force, so it is suitable for rolling thin sheets.