The Application Research On Position Servo Control Of Eccentric Flying Shear

Cut to length (CTL) line is the finished product line which can cut the steel coil to customer required length steel board. The fixed ruler flying shear is applied abroad in CTLs, because using it can make the line produce steel board in high speed and continually. A CTL line in baosteel use an bridge structured fly shear, which is the third generation imported flying shear. The tolerance of fixed ruler is lower than ± 0.5mm. Our understanding about the motion control principle of this shear can be improved by the research of it, then our maintenance ability will be improved to avoid going wrong in fault recover process. It provides a guide to the machine importing and self-developing in future.We start the research with the mechanical structure and control system configuration of GEORG flying shear. We get the function and control theory of every axis in fixed ruler motion control through the requirement of this flying shear cutting process. From the only one speed reference curve of this flying shear, we get the position serve control model of upper blade, refer to the literature of smoothing algorithm of other flying shears and NC machines serve control. The application of this model in middle and long material cutting is given as an example. Base on this model, we derivate the trajectory planning algorithm of this shear at the determinate ruler length. The interrelated interpolation methods are also given in the every phase of this flying shear. Thus the almost entire motion control rule is taken.From the safety of man and machine, the GEORG flying shear control system has been provide some self diagnostic function. It gives some alarm message to us when a accident happens to the flying shear. The ameliorate requirements and schemes are given out in this paper, base on the insufficiency found in using this flying shear. We hope these measure will be taken in the design and making the new flying shears, to improve the system reliability and to reduce the difficulties what exist in fault recover.