Design By Analysis And Its Application In The Design Of Liquefied GAS Rail Tank Car

Conventional design standard , based on the theory of elastic invalidation rule , deducing calculating formula for engineering application, figuring out the maximum key stress, confining it to the approved value, setting limitations to the structure form on part of the container without calculating partial stress, is a standard derived on the basis of the maximum key stress theory in elastic invalidation rule and long-period experience in practice.Following the advancement and development of technology , the specification and other requirements for container are getting so crucial that conventional design standard taking GB150 steel pressure vessel as a representative no longer fits the role. Whereas analyzing designstandard JB4732 steel pressure vessel---analyzing design standardadopted higher stress limitation, made a precise calculation of stress on each part of the container, demanding more on material selection, improved the manufacturing standard and further insured safety and reliability of the container. Design by analysis has been broadly used in engineering practice in recent years.The strength calculation for the design of liquefied gas railway tank car has adopted GB150 as standard and long period experience in practice as basis for a long time. Whereas during the finite element calculation, there always shows that partial stress exceeds the approved stress even the yield stress. In static strength test according to TB/T1335 assessing regulation for railcar strength design and test, we also found excess in partial stress. But in practical running, the case that cars being destroyed for excess in partial stress is rare.Aiming at the problems discussed above, the article proposed to adopt design by analysis, to make a detail analyse and calculation of partial stress and to assess containers with different stress strength with accordance to different approved limitation in railway tank car design. The article made an analyse and calculation on actual structure withFinite Element Analysis Software with accordance to design by analysis method. The result shows that the stress strength meets the demand of analyzing design standard and calculated stress nearly equals to the stress obtained in the static strength tests which account for the feasibility of design by analysis. The article shows us that it is economical, reasonable, safe and reliable to adopt design by analysis method in liquefied gas railway tank car design through comparison between the two methods.