Controlled Cooling in Continuous Casting

Controlled Cooling in Continuous Casting

Článek recenzovaný mimo WoS a Scopus

Cooling is an essential part of the continuous casting technology. The new generation of mist nozzles allows controlling the cooling intensity in wide range by setting a combination of water and air pressures. The paper presents experimental method for measurement of heat transfer parameters of typically used water and water-air (mist) nozzles. The experimental apparatus uses the identical spray conditions to the conditions in plant. The nozzles are tested for pressure setting, for influence of casting speed, for behaviour in the overlapping areas. The tests provide the description of heat transfer coefficient and heat flux distribution on the cooled steel surface. The knowledge of these parameters is necessary for any advanced control system. Another area where the knowledge of cooling parameters is necessary is design of cooling sections for casting machine and preparation of cooling model for steel groups. The paper presents new experimental findings in specification of the Leidenfrost temperature that is sharp surface temperature border between high and low temperature regions where great difference in cooling intensity is observed. The paper also deals with the problems of homogeneity of cooling along the nozzle spray angle and in the overlapping area where thermal strips occur. Sensitivity of this problem to the pressure of coolant is discussed.

Cooling is an essential part of the continuous casting technology. The new generation of mist nozzles allows controlling the cooling intensity in wide range by setting a combination of water and air pressures. The paper presents experimental method for measurement of heat transfer parameters of typically used water and water-air (mist) nozzles. The experimental apparatus uses the identical spray conditions to the conditions in plant. The nozzles are tested for pressure setting, for influence of casting speed, for behaviour in the overlapping areas. The tests provide the description of heat transfer coefficient and heat flux distribution on the cooled steel surface. The knowledge of these parameters is necessary for any advanced control system. Another area where the knowledge of cooling parameters is necessary is design of cooling sections for casting machine and preparation of cooling model for steel groups. The paper presents new experimental findings in specification of the Leidenfrost temperature that is sharp surface temperature border between high and low temperature regions where great difference in cooling intensity is observed. The paper also deals with the problems of homogeneity of cooling along the nozzle spray angle and in the overlapping area where thermal strips occur. Sensitivity of this problem to the pressure of coolant is discussed.

Continuous casting Cooling…..Heat transfer…..Experimental method

Continuous casting Cooling…..Heat transfer…..Experimental method

HORSKÝ, J., KOTRBÁČEK, P.

14.09.2004

Chinese Society for Metals

Peking

The Chinese Society for Metals

Supplement 2004

0449-749X

Chinese Society for Metals

39

2004

Čínská lidová republika

342

346

5

http://hdl.handle.net/