The Development Of 80MN Electric Screw Presser Control System

With the development of national defence industrial, 80MN electric screw presser mentioned in this thesis, which is the unique equipment in china, plays a significant role in aerospace field. The heat-forging technology of new high- temperature alloy sets a higher target to control performance of electric screw presser. Electric screw presser is needed to perform high hitting force and precise forging process to improve the properties of metals. Based on the application of electric screw presser, the thesis applies the advanced control structures to develop the electric screw presser control system.First, the developments of the screw presser and screw presser control system are introduced and the key technical problems and main research content of the electric screw presser are put forward. According to the analysis of "force--energy" relationship of electric screw presser and the solution of die-forging deformation force and deformation work with principal stress theory, the thesis advances a method to set forging energy. Meanwhile, according to the analysis of vibration model of electric screw presser and hitting force dynamics model, a structure is presented which measures the hitting force by means of strain electrical measuring methods with acceleration compensation. And more detailed performance and process is required on the strain gauges which is the core components of strain electrical measuring methods.By analyzing the structure and operation principles of electrical mechanical screw presser, electrical control theory and structure of electric screw presser are given out. Based on the control system hardware platforms of the industrial control computers and PLC and connection with Profibus-DP field bus, this thesis constitutes hardware of the electric screw presser control system.In this thesis, the entire operating process of electric screw presser is separated into seven steps and the concept of step chains is raised from the characteristics and judgment method of each step. According to the operation principle of electric screw presser and the requirement of forging process, program structure of eight main functional units is worded out with the core of step chains. PLC slave computer operating program and industrial PC host computer monitoring program constitutes software control system of the electric screw presser.The good performance and reliability of the control system has been proved in practical application. The forging products from it can meet all technical requests and the quality of products reaches aerospace level.