Research On The Design And Performance Test Of A New Type Of Fast Cooling Device

As an important part of China's national economy,the iron and steel industry has become one of the important symbols of China's economic strength and industrial civilization after decades of long development.The production of hot-rolled steel strip accounts for 30% of the steel production,which is an important source of steel production.The development of hot rolled strip mainly depends on TMCP,which can improve the quality,output and structure performance of products.It is known as “revolutionary technology of hot rolled steel production in the past century”.Among them,the controlled cooling technology is the controlled cooling technology system when the steel reaches the austenitic transformation temperature range,which makes the transformation structure refined and reasonable transformation,so as to obtain products with better structure and properties such as strength and toughness.The development of control cooling technology was transiting from the traditional laminar cooling to the new fast cooling.In recent years,the research of control cooling technology on the densification cooling device has made some achievements,and many new devices have been developed.Based on the investigation of the existing devices,according to the needs of small and medium-sized enterprises,a new type of fast cooling device with short start-up and stop response time,large adjustable cooling rate and high cooling capacity is designed in this paper.The structural parameters of the device are simulated,and the cooling condition test platform is built to test and evaluate its heat exchange performance and cooling capacity.This project is mainly from four aspects: the structural design of the new type of fast cooling device,the flow field simulation and structural optimization of the new type of fast cooling device,the construction and test of the test platform for the cooling conditions of the new type of fast cooling device and the analysis of the cooling capacity of the new type of fast cooling device.First of all,according to the cooling form,response characteristics and uniformity requirements of the new fast cooling device,the specific structure form of the new fast cooling device is designed from the outlet to the inlet,and through the flow field analysisand start stop response calculation,the preliminary assumption of the device is expected to be analyzed.Then,using the finite element software FLUENT to carry out the finite element simulation analysis of the important parameters of the new type of fast cooling device.The influence rules of the outlet layout,the inner header,the damping hole area,the side distance,the inlet diameter change and the inlet length are analyzed respectively,and the structural parameters are optimized according to the analysis conclusion.Secondly,self built cooling condition test platform is used to test the cooling and heat transfer temperature drop of the new type fast cooling device.The heat transfer coefficient is inversely calculated from the heat transfer temperature drop curve obtained from the test.The influence of steel plate material,water flow pressure,steel plate thickness and initial steel plate temperature on the heat transfer coefficient is selected and analyzed,and a comprehensive model of the heat transfer coefficient is constructed.Finally,the heat transfer performance of laminar flow device and laminar flow densification device is tested by using the cooling condition test platform,and the cooling temperature drop and cooling heat exchange rate of the new type of fast cooling device are analyzed,and different devices are simulated.The cooling capacity of the new type fast cooling device is analyzed.