Abstract: The steel pipe support of the chamfering machine of Julong Steel Pipe Co.,Ltd. a subsidiary of CNPC Bohai Equipment Manufacturing Co.,Ltd. frequently encountered with such a problem,i. e.,during the lifting operation,the pipe's upward movement was unleveled,and thus the final up-positions of pipes with different sizes were hard to be precisely controlled,and consequentially the machining efficiency of the chamfering machine was tremendously reduced. Addressing this problem,the electrical control system for the pipe support of the chamfering machine is modified by means of a number of advanced control techniques,including replacing the original solenoid valves with proportional valves,adding 2 hi-speed counting modules (FM) and 1 analog quantity output module (AO) to the PLC substation,and using the (Siemens MP377) touch screen,etc. As a result,the said problem is successfully fixed.