Tube-lathe is mainly used as processing the petroleum pipeline screw thread andrehabing the original pipeline screw thread.Because the design of its control system is quitedraggled,its work efficiency is low.To solve this problem and at the same time to improve theautomatic degree,we put forward numerical control reformation of the tube-lathe.This paper introduces altering design of the tube-lather using FANUC numericalcontrol system.The point problems are expadated, electric design and PLC program anddebugging and implement of resumption of thread cutting, and assistant transmission systemdesign & reformation.After make use of the FANUC number control system to take care of the thread lather areformation to the CA6140, that tool, lowers labor strength, raise rate of production.Throughtest various technique index signs to arrive industry all and already standard,and the systemcirculate is steady.