Development And Applocation Of Automatic Control System Of The Steel Elongation

With the economic and social development，the status of cold-rolled strip steel in theproduction of iron and steel industry continue to improve, and flatness is an important indicatorof the measure of cold-rolled strip steel products’ quality. In a continuous production process ofcold-rolled strip steel, there will be a variety of board-shaped defects, in order to get a goodplate-shaped, to meet the users’ requirements of strip flatness, in continuous production lineoften use temper mill and stretching-bending straightener. Temper mill mainly through rollingforce and tension control to eliminate the strip yield platform， and stretching-bendingstraightener through tensile bending the strip to produce the plastic deformation，eliminate theshape defects. Elongation is an important deformation standard in flattening and stretch bendingprocess, therefore, how accurately controls the elongation of the strip in order to achieve thepurpose of improving the plate-shaped is a very critical issue.This subject is based on the project “300,000tons continuous annealing production line ofShandong Yuanda” from NEW BRP Electrical Equipments Co., Ltd, tension leveling technologyis elaborated, steel plate elongation control system is designed and put into use in practice, goodresults is achieved.From the following aspects of this subject has been studied:1. The development and current status of steel elongation is described and this researchsignificance is introduced;2. Tension leveling technical principles is elaborated, the equipment composition and thebasic parameters of stretching-bending straightening in the continuous annealing line isintroduced and the continuous annealing production processes is studied;3. The definition of steel plate’s elongation is analyzed to determine the measurementmethod of the steel sheet elongation; the tension control method of the tension roller is studied;steel elongation controller is designed;4.This control system’s electrical components is introduced, automatic control system of thesteel elongation is designed, including writing PLC program, debug transmission parameters,and the2-level computer control system is designed, its application in steel elongation control isstudied;5. According to production practice to summarize the effect of the control system,elaborated the problems encountered and proposed the improvement program.