Analysis On Mechanical Properties Of Support Structure Of Double-layer Net Rack Pillars Spherical Tank

A spherical tank is a chemical unit equipment, pressure vessel mainly used for storage of chemical supplies such as gas, liquid or solid. Because most supplies of spherical tank are flammable, explosive and toxic substances, once an accident happened, it often leads to disastrous consequences. In addition, because of the influence of alternating loads caused by earthquake, wind, pressure fluctuation, spherical tank always occurs tilt, collapse, cracking and other damage phenomenon, and as a result of this, direct and indirect losses usually are enormous.The overall structure of a large spherical tank is regular, but the local structure is not continuous, and the force situation is more complicated, meanwhile spherical tank withstands alternating loads caused by a variety of stresses. So we use analysis design method for analysis, design and verification, it is the only feasible method which is generally accepted. Such a design method is a huge workload, a long design cycle, demands on the quality of a designer. At present, mostly to use finite element method analyzes and designs spherical tank at home and abroad.The thesis analyzes and researches around a double-layer net rack pillars spherical tank developed by a pressure vessel corporation. Using three-dimensional design software creates this spherical tank solid model, and using finite element analysis program establishes finite element analysis model of the spherical tank. Because of particularity of shape of the spherical tank, we need researches appropriate finite element mesh methods to obtain high-quality hexahedral mesh model. We load self-gravity of the spherical tank, supplies pressure, wind, snow, earthquake and other loads respectively, using ANSYS static analysis and dynamic analysis to calculate the loads and get pillars, pull rods and shells of the spherical tank of stress distribution which is caused by deformation and displacement; and a single-layer pillars spherical tank of the same size loaded the same loads is calculated stress distribution and deformation of its structure. Comparing the two cases, we summary characteristics of stress distribution of double-layer net rack pillars spherical tank and differences with single-layer pillars spherical tank.The thesis involves a steel pressure spherical tank for petroleum chemical, energy, metallurgy and other industries has an important meaning and value. Analysis approach on mechanical properties of double-layer net rack pillar spherical tank is to explore the structure of new spherical tank. Currently the development of construction of spherical tank is toward upsizing and structural diversification. This study meets the development trend of today’s spherical tank, and has some guidance for the follow-up research and development of spherical tank. This study could help double-layer net rack pillar spherical tank to apply safely, and accumulates experience for the further development of larger, more diverse spherical tank.