A new type of self centring-hydraulic-expanding grinder mandre is degined.It has high centering accuracy,radial play eccentricity of locating surface can be controlled within 0.002 mm,and it is easy to assemble or disassemble,reliable clamp and good stability.Design points of crucial element are analysed,and technique as well as operating requirements is presented to guarantee accuracy of manufacturing and assembling.By means of actual production,it can satisfy ...