CONCLUSIONS 



1. Both the stacked-ring and the segmented-wall cylindrical pressure vessel 

 concepts are technologically and operationally feasible for construction of 

 large-diameter, high-pressure cylinders without recourse to welding. The 

 stacked ring is more economical and structurally sound than the segmented 

 wall, in which stress concentrations dictate the use of thicker walls and also 

 serve as potential sources of fracture. However, when interior size and pressure 

 capabilities are the only considerations, the segmented-wall concept permits 

 construction of considerably larger cylindrical pressure vessels than the stacked- 

 ring concept. 



2. The tie-rod end-closure restraint system is technologically and operationally 

 feasible and can be used with stacked-ring or segmented-wall pressure vessels, 

 but it is structurally less sound than the continuous laminated-yoke system 

 because of the many stress concentrations inherent in this concept. 



3. When a laminated-yoke end-closure restraint system is mated with a stacked- 

 ring cylinder, it results in an economical and structurally sound pressure vessel 

 for diameters and pressures in excess of 10 feet and 10,000 psi, respectively. 



ACKNOWLEDGMENT 



The pressure vessel models tested in this study were designed by 

 Mr. R. 0. Doty and Mr. B. M. Merrill of NCEL's Design Division, and the 

 photoelastic analysis of structural components was performed by Mr. J. R. Keeton 

 of the Material Sciences Division. 



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