METHOD OF CONTROLLING PRESSURE OF A WIDTH-VARIABLE AIR KNIFE IN A CONTINUOUS GALVANIZED LINE, CAPABLE OF APPLYING OPTIMAL CONTROL GAIN

摘要

PURPOSE: A method of controlling pressure of a width-variable air knife in a continuous galvanized line is provided to reduce plating deviation by applying optimal control gain according to pressure setting value of a secondary pressure control valve and edge mask variation of a width-variable air knife. ;CONSTITUTION: A proportional/integral parameter is input to a pressure control parameter input unit(2) according to the variation setting value according to the width variation of a steel sheet and pressure setting value of a second pressure control valves(7,8) on a gas pipe. The proportional/integral parameter is stored in a unit(1) for calculating control valve of a pressure control valve. The calculating unit proportionally/integrally calculates error between pressure setting value and current pressure and produces input value for first and second pressure control valve positioners(3-5).;COPYRIGHT KIPO 2011