Structural Design Of Ultra-fast Cooling System For Hot Rolled Strip 2150 Production Line

Strip steel after hot rolling temperature is higher,the cooling process after rolling directly affecting the mechanical properties of the steel product and organization,super fast cold as a new cooling technology,can realize accurate control of the temperature of the rolled strip.This paper carries out the work from the two aspects of ultra-fast cooling principle and equipment structure design,and gives a set of strip ultra-quick cold production technology and establishes the overall prototype scheme of the equipment.In this paper,the principles of heat transfer and superfast cooling are summarized and the common heat transfer modes are summarized.In this paper,the super-fast cooling process is compared,and the superfast cooling process is proposed.Then,CATIA software is used to establish the 3d model of super fast cooling system,and the location of each part is reasonably arranged.Using ABAQUS software to analyze the static force of the rolling shaft and bearing seat,the result shows that the part design meets the requirement of static strength.The modal analysis of the rolling shaft and the bearing block is carried out,and the results show that there is no resonance in the operation of the two parts.For the lateral baffle parts for structural topology optimization,the optimized parts on the premise of meet the strength and stiffness,as far as possible to reduce the part weight,improve the installation convenience,saving the use of materials.In this paper,the static analysis of the rolling parts and bearing housings of key parts is carried out.The strength and stiffness of the designed parts are judged to meet the requirements of the system.After the modal analysis of the two parts,the natural frequencies obtained are far away from their corresponding operating frequencies,and the system stability meets the requirements.Finally,topology optimization techniques are used on the baffle components to simplify the design structure and reduce the overall weight of the system.The strength and stiffness state of the rolling shaft and the bearing housing under thermal load are checked,and the results satisfy the requirements for strength and rigidity.Strip cooling process in this paper,the relationship between water jet velocity and the strip steel heat transfer were analyzed,and the analysis results show that high jet velocity is advantageous to the water flow in the strip surface,can improve the cooling effect of the strip surface.The thermal stress analysis of rolling shaft and bearing seat at high temperature shows that the thermal stress is less than that of material allowable stress,and the deformation is less satisfying.In this paper,through the post-application test data analysis of the ultra-fast cooling system,it is concluded that the ultra-rapid cooling system controls the temperature of the hot-rolled strip by switching the spray-cooling group without increasing the total amount of water used in the system.The lower limit of the temperature of the rolled strip is lower than the lower limit of the temperature after cooling with the conventional laminar flow,the final cooling temperature of the strip reaches the ideal requirement;for the Q235 B,the ultra-fast cooling can increase the yield of 40-50 Mpa and increase the tensile strength by about 30 Mpa,the performance indicators can meet the requirements of Q235 B and Q345 B products,but the strength index can only reach the lower limit of Q345 B standard.