The Investigation Of Large Counter-Gravity Casting Equipment And Control Technology

This paper investigates the large counter-gravity casting equipment which can be used to product large complex thin wall castings, the controlling technology and counter-gravity casting process is also studied. Firstly, we analyze the mechanical structure of large counter-gravity casting equipment briefly, and design all parts involved. Secondly, we put forward the design scheme of casting trolley used to transport casting mold. Thirdly, the paper provides lots of information on the pneumatic system of the equipment, puts emphasis on the design of gas-in part, adjustment part and gas-out part of different systems.The large counter-gravity casting equipment adopts advanced controlling schemes for hardware and software. This paper mainly investigates the design theory of process controlling parts, including signal acquisition and output. The software used for the system is written by orient-object Delphi and macro assembly language. Especially, the author works out a new design method of PID controller. The PID algorithm is improved through'fuzzy theory. By this way, the control precision and dependability of counter-gravity casting equipment can be improved obviously. Finally, this paper perceives the process controlling of counter-gravity casting and its influence on the quality of castings. The works of this paper is of special importance on the production of large-size thin-wall castings of high-quality.