A three-legged ejector sleeve is adopted in the die casting mould to take cast stripping mould, the problem that the cast difficultly demould is solved. 采用三脚推管推出铸件，解决了轴套铸件脱模难的问题。
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。