Second-to-last stage moving blades for half-speed large-capacity nuclear power steam turbines

Abstract

The invention provides a secondary-secondary last-stage moving blade for a half-speed high-capacity nuclear turbine. The secondary-secondary last-stage moving blade comprises shroud rings, a blade work portion, a middle body and a blade root. The height of the blade work portion is 905 mm, the molded line is a variable-section twisted blade, the area of the section of the blade is gradually reduced along with increase of the height of the section of the blade, and relative twisting exists between two adjacent sections. The shroud rings are located at the top of the blade work portion. The blade root is located at the bottom of the blade work portion, and is a laterally-mounted, large-circular-bead and low-stress-concentration longitudinal tree-shaped blade root. The middle body is located between the blade work portion and the blade root, and the width of the middle body is identical to the axial width of the blade root. The shroud rings, the blade work portion, the middle body and the blade root are integrally formed. In a static state, a clearance between the work faces of two adjacent shroud rings is zero. The adjacent shroud rings at work rotating speed are coupled to enable the whole ring of the secondary-secondary last-stage moving blade to be connected into a set. The secondary-secondary last-stage moving blade can be suitable for an AP1000 and future CAP1400 / CAP1700 nuclear power steam turbine generator unit, and the requirement of the half-speed high-capacity nuclear turbine for aerodynamic performance and strength can be met well.

Description

technical field [0001] The invention relates to a second-to-last stage moving blade for a half-speed large-capacity nuclear power steam turbine. Background technique [0002] With the development of society and the expansion of the scope of human activities, human demands for energy are not limited to expanding the scale, but more consideration is given to environmental protection. Nuclear power has won the favor of all countries because of its high power, high efficiency, controllable environmental pollution, and extremely low carbon emissions. It can be predicted that nuclear power has a huge market in China and is closely watched by domestic and foreign power plant manufacturers. As a key component of large-capacity nuclear power steam turbines, the performance of low-pressure long blades determines the power level and efficiency of nuclear power steam turbines to a large extent. Usually, the long blades of the steam turbine refer to the last three-stage blades of low p...

AI Technical Summary

Problems solved by technology

Since the capacity of the third-generation reactor unit has increased by 20%-80% compared with the current 1000MW level unit capacity, coupled with the requirements of low cooling water temperature in the coastal and central and northern regions, the original 600mm and 700mm height levels of the sub-terminal length The exhaust area of ​​the blade is too small, which can no longer meet the existing demand

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