The Plate Mill at Bhilai Steel Plant (BSP) has two reversing stands, one functioning as the roughing mill, and the other as the finishing mill. The nominal thickness of the slab is 245mm, which is reduced to about 40mm as thick plates in the roughing mill and the thinner plates are processed further in the finishing mill. The Plate Mill is now undergoing a major revamp with the main component being the hydraulic automation gap control (HAGC) and the supporting automation systems. The HAGC is backed up by proper sensors, instrumentation, microprocessor-based control equipment working in real time. The installation of the HAGC provides for controlling thickness variations due to process variables like plate temperature, mill spring, and so on. Mathematical models for both off-line simulation and adaptive mill setup have been developed indigenously for automatic control of plate thickness in the revamped Plate Mill. The control of thickness of the plate from head to tail is envisaged as a two-step process, viz., (i) a Level II Adaptive Algorithm, where an optimum drafting schedule generated "on the fly" is downloaded as reference points for the Level 1 automation and (ii) a Level 1 Feedback Controller for applying the necessary correction in the roll gap, for process deviations during rolling. The off-line mathematical models have been validated with extensive data collected from the mill. Once they are implemented online, it is anticipated that continuous updating will improve its performance and will reach international levels of performance guarantee. © 2010 Taylor & Francis Group, LLC.