Application And Improvement Research Of Mechanical Seal Of Molecular Still

Molecular distillation technology is widely used in the food industry,fine chemical industry and pharmaceutical industry,and Molecular still is one of the important and necessary equipment of the process.Molecular distillation process must operate under the condition of close to absolute vacuum,so molecular still must be required to achieve near zero leakage.But still the stirring shaft mechanical seal is prone to leakage location,impact on the whole still greatly,therefore,the best sealing effect is to ensure the work stability is the key factor of distillation kettle,so the distillation kettle mechanical seal application is especially important.In order to improve the reliability and prolong the service life of the mechanical seal,and obtain the stable production condition,this paper takes the company's existing mechanical seal as the research object,and carries out the application research in various aspects.First,the paper describe the mechanical seal failure phenomena in the daily production of the company of four molecular stills,and statistic the numbers,and analyze the reasons in the past ten years.Using the Weibull distribution function for the reliability analysis and evaluation of mechanical seal of company,it is necessary to study this subject.Then,the failure mechanism of the distillation kettle seal is studied in depth,and the relationship between the mechanical seal failure and the swing of the spindle,the cooling method and the sealing material is found out,provides the direction for the transformation of distillation kettle sealing machine.In order to solve the problem of molecular still mechanical seal selection,through a comparative study of different selection method,that method uses the general selection and level selection combination selection method is effective for the molecular still mechanical seal,and the pressure end and the end temperature is calculated and verified,forming a reliable selection method the system can be used as references for design.Finally,based on the failure mechanism and selection method,analyzes the existing 207-200 type mechanical seal is the use of problems and shortcomings,put forward the improvement methods and measures,and verified by the mechanical seal of the actual use of the test results of the mechanical seal performance before and after improvement were compared and the results show that the improved mechanical seal reliability stability has been significantly improved.At the same time,on this basis,the paper puts forward a set of mechanical seal daily operation,maintenance,maintenance measures and procedures,in order to further reduce the mechanical seal failure rate,extend the operation cycle.Through the research of mechanical seal,a set of effective,operable and convenient type selection method and maintenance management method is obtained,and the mechanical seal with good performance and longer service life is obtained,which creates a good condition for stable production.At the same time,it also puts forward the mechanical seal leakage and the sealing surface of the effective height of the on-line monitoring device and convenient installation of the broken mechanical seal has a lot of research space.