Abstract: Piercer is an integral equipment to seamless steel tube rolling, to which the problem that a pause is necessary when readjusting rolling parameter is unsolvable for long, thus reducing the productivity greatly. Nowadays the BaoSteel has implemented the on-line readjustment of an important rolling parameter, i.e., the guide disc revs, by rebuilding the Diescher guide disc on SWW skew rolling piercer. Describes the way to rebuild the Diescher guide disc and, based on ICA, the ICR is introduced in solving the optimal revs of the disc. A model is developed for the optimal revs of the disc. Test results show that the optimal revs given by the model can improve both product quality and productivity effectively with energy saving realized.