Simulation and Experiment of Electro-hydraulic Servo System and Its Application in Step Controlled Hot Coiler

Hot coiler is a key equipment in the production line of hot strip mill. As the traditional coiler cannot timely avoid the difference between layers during coiling process, which results in strong impact and vibration to cause harm to the equipment. The method to solve this problem is using step controlled coiling roll technology. The electro-hydraulic servo system used for the first step controlled coiler is designed. To meet the requirement of dynamic response of step control, understand and master the know how of this technique, to provide the technical basis for designing and manufacturing the real coiler, and to accumulate the experience in on-site debugging, a analog test system is built by reference to the real coiler. In the light of this test platform, the nonlinear mathematical model of electro-hydraulic servo system including pipes and the coiling roll is established. Then simulation and test are carried out. The result verifies the correctness of the model. The type and size of the used components, the structure and parameters of controller are determined by digital simulations. Finally the designed electro-hydraulic servo system is successfully applied in the real step controlled coiler first domestically. The practical operation results of step control confirm the correctness of research work. The research results have theoretical and practical significance for promoting wide application of the step controlled hot coiler technology in China. copyright 2011 Journal of Mechanical Engineering.