1·The mill comprises roll changing hydrocylinder (1), with rolling mill group (3), roll changer (2), post (4), worm wheel lifting gear (5), U-shaped frame (7), rotation ear (8) and bolt (9).
其特征在于本轧机包括换辊液 压缸（1）、换辊小车（2）、轧钢机辊组（3）、立柱（4）、蜗轮升降机构（5）、U型 架（7）、转动转耳（8）、连接螺栓（9）；
2·The familiar structures of loose core and ejector of hydrocylinder in injection mold were introduced. The calculating method of selecting hydrocylinder and the key points in using it were discussed.
介绍了液压油缸在注塑模具中常见的抽芯及顶出结构，并对选取油缸的计算方法和使用要点进行阐述。