Strength Assessment of Equipments and Piping of WWER Nuclear Power Plants

Abstract

The Standard Technical Documentation (STD) of The Association of Mechanical Engineers (A.M.E.), Section III “Strength Assessment of Equipment and Piping of Nuclear Power Plant of VVER type” provides guides and requirements for elaboration of: - conclusive documentation for equipment, piping and their supports, manufactured and supplied or manufactured for replacement, for nuclear power plants of VVER type, 440 MW and 1000 MW; - conclusive documentation for repaired, replaced and innovated components of equipment, piping and their supports for nuclear power plants of VVER type, 440 MW and 1000 MW; - conclusive documentation on continuous lifetime usage of equipment, piping and their supports during the operation of nuclear power plants of VVER type, 440 MW and 1000 MW and determination of their residual lifetime; - documentation on degree of compatibility of equipment, piping and their supports for nuclear power plants of VVER type, 440 MW and 1000 MW with the ASME Code Section III, Division 1. The following principles of the Section III are discussed in the presentation: general structure of the Section III; design specifications and operational conditions; calculation of allowed stresses; stress categories groups (σ)1, (σ)2, (σ)R, and (σaF); limit criteria for stress categories groups; loading blocs; assessment on fatigue; assessment of two-frequency cyclic loading on fatigue; fatigue correction factors for multiaxial stress states and gradient of stresses, corrosion, welding and radiation; limits; determination of load at collapse; use of elastic and elastic-plastic analyses; elastic-plastic carrying capacity of components; stiffness of the nozzle opening.