Large, High-vacuum Annealing Furnace Temperature Control System

Vacuum anneal has already developed the main researching and developing aspect in metal heat treatment along with the advance of metal accessory performance and precision requirement in equipment recently. Accurate and steady control of temperature affects the quality and eligible rate of annealing work pieces directly in the course of vacuum anneal. The accurate control of the work pieces temperature in vacuum annealing furnace is a typical nonlinear large time delay and cross coupling complicated problem. In order to realize the accurate control of the work pieces temperature, this paper analyses the diathermanous characteristic, obtains two control models via the methods of the optimized the parameters of the dynamitic model via genetic algorithm and the neural network that weighs and bias were optimized by genetic algorithm and realizes the accurate control of the work pieces temperature via the method of variable argument PID controller that PID parameters were optimized by adaptive immune genetic algorithm, which combine with the strongpoint of the physical meaning clearly and strong complete ability to search for optimization of adaptive immune genetic algorithm. The hardware of controller is made up of the SCL500 PLC that made by Rockwell/Allen-Bradley, monitor software is implemented by configuration software Rsview32 that made by Rockwell, and the control algorithm was implemented by C++ program language in upper industry control computer. The practical results show that the control system in this paper has a good reliability, adaptability and robustness and can reach to the manufacture technics requirements of vacuum anneal.