Research On Pressure Vessel Of Rectangular Autoclave

As one of the core components of autoclave, the properties of sterilizing vessel woulddirectly affect the product performance and working life. At present a cylinder was used in themost autoclave, while a rectangular vessel which manufactured by welding after sheet metalbending and had a low productivity was only used in some high capacity autoclave. Consequently,it does have a positive significance of intensifying market competition to design a new vessel ofautoclave which is easy-machining and reliable.This paper undertook a study and discussion of autoclave from three methods includingexperimental study, theoretical analysis and numerical simulation. At first, experimental researchon thin wall cylinder of original autoclave was executed, which based on electrometric method.When the test pressure was at0.35MPa, principal strain at test points can be gotten. According thegeneralized Hook Law, principal stress can be transformed from principal strain. Although therewas a difference between measured values and theoretical values, the difference was slight. Andthe two values both demonstrated the stress condition of cylinder. Further more, experimentalresult could be referred to revised structure design later. Then, force analysis for rectangle vesselwas carried out as a mechanical model of curved beam, which based on a shell model that ignoredthe influence of end closures. Introducing the concept of flowing radius, the minimum life sectionjust located the maximum flowing radius. After that, the computing formula and strength checkingof shell thickness was deduced. On the basic of former theoretical analysis and practical experience,this paper had design the shell, head, tubes and door in details. In the fresh design, vessel volumewas about10L; each joint between two side plate had an "R=30mm" fillet; both nominalthicknesses of shell and head were4mm. And they two are formed with an entirety drawing. Thenew rectangle vessel has many advantages like simple in structure, easy to machine, shape elegant,more effect space utilization, etc. Finally, structure static stress analysis on designed vessel haddone with the famous nonlinear FEM software ABAQUS. The model could be meshed withstructured meshing and swept meshing. And to apply boundary condition according to the realoperating condition. When the load was0.35MPa, the maximal equivalent stress came out in thefillet, which was just on the maximal fluent radius. Hereby, the result of numerical simulation wasaccordance with theoretical analysis.The result showed that in order to achieve the same strength with cylinder, the wall thick ofrectangular vessel should be thickened. However, the utilization of rectangular vessel was more than cylinder. As a result, for a same working volume, consumption of sheet material of rectanglevessel was litter than cylinder. In sum, when using rectangular vessel instead of cylinder, it wouldnot increase the material cost.