Mesh Belt Furnace Control System

The web-strip hot furnace is a normal appliance of work pieces heat treatment in manufacture, which commonly used in marching and the heatment of the metal materials. It is also a vital appliance in the heat treatment of chain, which is the last working procedure in chain made. The strength and toughness of chain can be influenced by this procedure directly.In this thesis, the heating process of the web-stripe hot furnace is studied deeply; the main factors of affecting control accuracy production quality are analyzed too. There are several temperature sections in a web-strip hot furnace, each section is different from the other on technics. They are coupled and influenced each other. It is very difficult to set up an accurate math-model of a web-strip hot furnace. The normal PID control system cannot improve the product quality.In the early of 1980s, automation instruments controlled the web-strip hot furnace popularly, whose controller is analogy PID adjuster. In the later of 1980s, control based computer is applied in web-strip hot furnace, its digital controller is the PID too. The quality has advanced but it cannot reach our target. The essential reason is just because of the complexity of the control object itself. As time goes on, fussy control becomes an effective tenique, which widely used in process control industry. Against at web-strip hot furnace characters such as nonlinear, tune-varying, large time delaying, bad vironment, etc, the fuzzy-PID control has been taken in the system, meanwhile, outline compensation has also been taken for the temperature of contiguous sections.This system based on AT89c51, it contains I/O, interface between computer and human, system software. It has been used in ZuZhou Cham Manufacture. They show us that the control quality reached the technics, production quality and the rate of qualified product advanced, energy and consumption lowered.In conclusion, this system has improved their benefit.