Structure Design And Performance Study Of A New Two Cooled Atomizing Nozzle For External Mixing Continuous Casting

China is one of the countries in the world that developed and applied the continuous casting technology earlier.The research on this technology began in the mid-1950s.At present,the iron and steel industry has developed rapidly in recent years,and its production has taken on a new look,which has resulted in a rapid increase in steel output.While improving the quality and production efficiency,the iron and steel industry has also significantly reduced production cost and effectively controlled environmental pollution.To investigate its essential factors,the core driving force comes from the technological progress of the iron and steel industry.Continuous casting technology is one of the important technologies in steel-making industry has obvious economic advantages and plays an important role in structural optimization for steel production.In order to improve the production efficiency,avoid the nozzle blockage and make the atomization effect uniform,this thesisanalyzed the contents and causes of nozzle blockage aiming at the problem that the secondary cooling nozzle of continuous casting in domestic iron and steel enterprises is prone to scaling and blockage.And the corresponding treatment plan was worked out,but it was found that the problem of nozzle blockage could not be solved fundamentally.Then,it was decided to change the structure of the nozzle and then change the working mode of the nozzle so as to avoid the blocking phenomenon.Through four improvements to the nozzle structure and the addition and improvement of water volume,water pressure and filtration device,this new type of atomizationnozzle characterized with air cooling,tangential atomization,reverse swirl and double-filtration external mixing water has finally been developed.The key development technologies includes external mixing atomization of water and air,cooling of the nozzle body by air in the nozzle,formation of reverse swirling flow of water and air in the nozzle to improve the atomization effect of water,tangential collision and mixing of water and air,and filtration of water and air before entering the nozzle.Aiming at the newly developed nozzle,the structure and function of the nozzle was analyzed,in order to find the relationship between the performance and various parameters of the nozzle through experiments.It was hoped that by looking for this relationship,a better working state of the nozzle could be achieved.This thesis analyzed the influence of water flow,pressure and other factors on the work of the nozzle,carried out the analysis of the thermal performance of the nozzle,and finished offline experiments.Based on a large number of experimental data and offline experimental results,this thesis was analyzed under which working parameters the nozzle can reach the best state.After a long period of work,this new nozzle worked perfectly normal and achieved the expected results,comparing withother nozzles under same condition that were completely blocked,did not spray water directly,the water flow was irregular in shape,the injection angle changed,and the water flow formed a thin line.