TEMPERATURE STRESSES AND OPTIMUM RATIO OF THE INNER AND OUTER RADII OF THE CYLINDRICAL PARTS OF PRESSURE VESSELS OF STEAM GENERATING SYSTEMS
DOI:
https://doi.org/10.20998/2078-774X.2016.09.16Анотація
The strength condition of the cylindrical parts of pressure vessels (water drums, collectors, heating surfaces, etc.) of steam-generating systems, which takes into account stresses due to the internal pressure and thermal stresses. Stresses due to internal pressure and temperature stresses are obtained using all-known results of the theory of elasticity for infinite cylinders. It is assumed that the strength of the cylindrical parts of pressure vessels of steam-generating systems is limited due to the formation of the plastic deformation in one point at least. The theory of maximum shear stress is used to formulate the strength condition. A geometric interpretation of the formulated strength condition is considered. The strength conditions for cylindrical parts of pressure vessels is reduced to the inequality that under given structural material properties restricts the possible values of the internal pressure and temperature drop across the wall thickness. The geometrical interpretation of the strength condition proposed for the cylindrical parts of pressure vessels in the base of the graphical representing of the solution of the inequality, corresponded to the strength condition. Graphical solution of the pressure vessels strength condition was presented on a coordinate plane the internal pressure - the temperature drop across the wall thickness. It is shown that the allowable by the strength condition the values of the internal pressure and temperature drop across the wall thickness in the coordinate plane occupies the limited area in the form of the right triangle. Proposed geometric interpretation allows us to determine the optimum value of the relationship between the inner and outer radii for the strength of cylindrical parts of pressure vessels of steam-generating systems.Посилання
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