Abstract:Coolant piping is the key component of pressure reactor in the nuclear power plant. Its processing quality directly affects the safe operation of nuclear power plant. According to the coolant piping technology bottleneck in the tube blank lathe machining process, the traditional machining process defects were analyzed; combining with the characteristics of DL250 CNC lathe, a set of practical and effective optimization processing scheme was put forward. So low efficiency, high cost, big labor intensity in turning of the coolant pipe are solved. It accumulates experience for turning overweight, oversized shaped workpieces.It has actual popularizing significance for enterprise.