Оценка остаточного ресурса конструкций проточной части агрегатов ГЭС и ГАЭС с учетом трещиностойкости

Abstract

Предлагаются методики и пакеты прикладных программ для исследования статического и динамического НДС, оценки ресурса и долговечности крышек, рабочих колес, камер рабочих колес агрегатов ГЭС и ГАЭС. Получены численные результаты, позволяющие оценить ресурс элементов гидротурбин с учетом реальных условий эксплуатации. Проведено сопоставление расчетных и фактических данных по состоянию исследуемых объектов. Эти результаты дадут возможность конструктору обосновать необходимость модернизации существующего оборудования ГЭС.The regulatory document "Calculation of residual operation life of HPP and PSP turbine water passage elements. Instructional guidelines" СОУ–Н МЕВ 40.1–21677681–51 is developed, in this document the following is proposed: methods for the static and dynamic strain-stress state inspection, estimation of life and longevity of head covers, runners, runner chambers of HPP and PSP units. The existing defects’ influence on the structure longevity is taking into consideration. The potential theory taken with the finite elements method and boundary element method is applied. The methods developed in the regulatory document are used for numerical analysis of the strain-stress state and estimation of the residual operation life of the most metal-intensive structures of the hydraulic turbine water passage, the replacement of these elements presents severe difficulties. These elements are: covers and linings of runner chambers made of steel grade St3 of hydraulic turbines PL20/661-В-930 of Dniprodzerzhynsk HPP operated under the conditions of multicycle dynamic stress, the total service life of which after the units’ modernization will constitute not less than 40 years. The numerical results are obtained, they allow to estimate the hydraulic turbine elements’ life considering actual operating conditions. Design and actual data on the state of the objects under investigation are compared. The scope of modernization for efficiency guarantees fulfilment and the guaranteed power generation of modernized hydraulic turbines is proposed.