Análise de tensões em tubulação de aço para adução de água

Abstract

This paper presents a methodology for the evaluation of the acting stresses on pipes of penstock type, used to furnish water to the hydraulic turbines of hydroelectric power plants. The analysis considers the load cases in accordance with the Brazilian standard NBR 10132:1987 – Calculations of penstocks. It presents a method for determining the maximum normal working pressure, due to the water-hammer effect, based on the preliminary layout of the piping system and the hydraulic characteristics of a ploy. Based on the literature and the applicable standards, the thickness of the conduit, of the supports and of the manhole are estimated, thus defining the other loads acting in the system. Based on the pipeline structure, the stress state at critical points is determined by calculating the principal stresses and the structure is checked in accordance with the Henck-Mises theory. Finally, the methodology is evaluated by comparing the results to a computacional model of the pipe, developed in the commercial software of stress analysis ANSYS 13.0.