| With the development and advancement of science and technologies, the requirement progressively increases for higher qualities and better processing of cold strip. A continue heat treatment production line is a new type of heat treatment equipment developed for increasing speed and improving the quality of the strip, which combining cleaning function, annealing heat treatment, and skin pass for strip into a associated production line. Vertical Continue Annealing Furnace (VCAF) is the key process equipment in the line.The key technology is for controlling temperature of strip in heat treatment process if better mechanical characters of strip are obtained. There are many affecting parameters in VCAF. These parameters include in equipment configurations (the distance between jet pipes and strip, the arranging method for jet pipes, the diameter of jet holes, the diameter and arranging method of radiation tubes, the distance between radiation tubes and strip, etc), the strip parameters (thickness and width), and process parameters (the speed of strip, the temperature and speed of gas, the opening number of radiation tubes, etc). The parameters are affected each other, and they affect temperature of strip all together. The model of temperature of strip for production control from foreign company only consists of the strip parameters, strip speed and opening number of radiation tubes, not equipments parameters, temperature and speed of gas. Therefore, there are two problems for analyzing annealing furnace: the model from foreign company is difficult to be understood principle but used; the model of strip temperature for theory research is deficient. We must found the theory research models for attaining ability self-determination theory analyzing and a production control model from the theory research model. The theory research model should include in all equipments configuration parameters, strip parameters, and process parameters. The theory research model is not found in reference papers. The thesis perfectly analyses the characters of heat transfer system in VCAF and brings forward in innovation a set of new theory research model including in equipment, strip and process parameters. The control models for strip temperature for production are obtained from the theory research models.The main contents of the thesis consist of 5 contents: analysis on conduction heat transfer of strip, analysis on normal forced convection heat transfer, proposing the calculating temperature models of strip on jet impinging convection heat transfer in Jet Preheat Furnace (JPF) and Rapid Cooling Section (RCS), and building calculating temperature models of strip on radiation heat transfer in Radiation Tube Furnace (RTF). Main contents of the study are summarized as follows:①Analysis on conduction heat transfer of stripThe relation is founded on strip instantaneous temperature, boundary temperature of strip, inner temperature in furnace, heat transfer coefficient and the Newton's cooling law according to equipment configuration, conduction characters of strip, and characteristics of transfer system of JPF, RTF and RCS,②Study for calculating temperature models of the strip on normal forced convection heat transferThe characteristics of the moving strip are analyzed according to the basic principle on a fluid flowing over a stationary surface. The boundary layer on the strip surface can be considered as turbulent flow according to the relation between the strip and the rollers in furnace. The calculating models are built by using the differential coefficient method for instantaneous heat transfer coefficient and instantaneous temperature of the strip. Then, they can be integrated to gain models for calculating the average heat transfer coefficient and strip temperature. The data errors are less than 5% by comparisons between the calculation data and production data.③Proposing calculating temperature models of the strip on jet impinging convection heat transfer in JPFThe convection heat transfer between strip and heat transfer system is analyzed in JPF using the jet impinging heat transfer principles according to equipment configuration parameters (the distance between jet pipes and strip, the arranging method for jet pipes, the diameter of jet holes, etc), the strip parameters (thickness and width), and process parameters (the speed of strip, the temperature and speed of gas, etc). The jet impinging convection heat transfer is analyzed between strip and heat transfer system. The relation model among Nusselt number, Prandt number and Reynolds number is proposed with coefficients and powers. The theory research models of instantaneous and average strip temperature are proposed. The model for production controlling temperature of strip is proposed from theory research model. The calculating data are basically accordance with production data.④Proposing calculating temperature models of the strip on jet impinging convection heat transfer in RCS The convection heat transfer between strip and heat transfer system is analyzed in RCS using the jet impinging heat transfer principles according to equipment configuration, the strip parameters, and process parameters. The jet impinging convection heat transfer is analyzed between strip and heat transfer system. Using the numerical value simulation method, the relation model among Nusselt number, Prandt number and Reynolds number is proposed with coefficients and powers. The theory models of instantaneous and average strip temperature are proposed. The model for production controlling strip temperature is proposed from theory model. The calculating data are basically accordance with production data.⑤Proposing calculating temperature models of the strip on radiation heat transfer in RTFBased on the fundamental radiation heat transfer principles, the models of radiating heat transfer rate are proposed for description of the relation between strip and system by analyzing relation among equipment configuration parameters (the diameter and arranging method of radiation tubes, the distance between radiation and strip, etc), strip (thickness and width) and process parameters (the speed of strip, the diameter, arranging method and the opening number of radiation tubes, etc). The calculating models are proposed for instantaneous radiation heat transfer rate, radiation heat transfer coefficient, and boundary temperature of strip applyed the Newton's cooling law, heat transfer between strip and system, and conduction heat transfer. The theory research models of instantaneous and average strip temperature are proposed. The production controlling model of strip temperature is proposed from theory model. The calculating data are basically accordance with production data.The theory research model and production control models, research methods and results in the thesis can be used in theory analyzing the annealing furnace and production controlling for strip temperature. The models can offer important reference and theory foundation for researching heat treatment process. It is a new exploration on theoretical innovation on calculating strip temperature for 3 furnace sections of JPF, RTF and RCS in VCAF. The models and theories can become important action for theory analyzing continue annealing furnace and production control.
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