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and an exit section. The entry section consists of an unwind stand, a tension leveller, and an entry accumulator. Operations such as wash, coat, and quench on the web are performed in the process section in the case of aluminum and steel webs, and printing, perforating, and laminating in the case of other consumer prod-ucts. The exit section consists of an exit accumulator and a rewind stand. A typical process line layout of an aluminum strip process-ing line is shown in Fig. 1. Accumulators are primarily used to allow for rewind or unwind core change while the process contin-ues at a constant velocity; they are also known by the name ‘‘fes-toons’ ’ in the non-metals industry. Dynamics of the accumulator directly affects the behavior of web tension in the entire process line. Tension disturbance propagation both upstream and down-stream of the accumulator has been noticed due to motion of the accumulator carriage. Although sufficient amount of work has been done in Refs. cumulator carriage, web spans, and the current methods used in controlling the carriage were discussed. A dynamic model for ac-cumulator spans that consider the time-varying nature of the span length was developed in Ref