Abstract: The electrical control of the thrust block is regarded as so critical for ensuring normal and highefficiency operation of the vertical cone type piercer(CTP)proper.Described here are the main aspects of the said thrust block electric control system,including the hardware configuration,the DC drive unit,and the PLC communication and related software programming,etc.The application of the S7-300 PLC plays a satisfactory role in precision-control of both positioning and process speed of the thrust block.