Final-stage long blade of steam turbine

Abstract

The invention provides a final-stage long blade of a steam turbine. The final-stage long blade comprises a blade root, a middle body, a blade body and a cover band which are connected in sequence, wherein the height C of the blade body is 1905mm; the relative value of the section area of the blade body is gradually reduced to 1.0 from 7.33 in the height direction of the blade body; the relative value of the molded line axial width W of the blade body is gradually reduced to 1.0 from 5.61; the relative value of the molded line circumferential width H of the blade body is gradually increased to 1.67 from 1.0; the relative value of the molded line chord length L of the blade body is gradually reduced to 1.0 from 1.40; the relative value of the maximum thickness TMAX of the blade body is gradually reduced to 1.0 from 5.89; a mounting angle alpha is gradually increased to 76 degrees from 12 degrees. The steam exhaust area of the final-stage blade is increased by increasing the length (namely the height) of a blade, and the steam exhaust area reaches 30m2 and can meet application requirements of nuclear turbines with different back pressures and unit levels, such as CAP1400 / CAP1700, and the like.

Description

technical field [0001] The invention relates to a moving blade installed on a steam turbine rotor, in particular to a last-stage long blade of a steam turbine. Background technique [0002] With the vigorous development of my country's nuclear power industry, the single-unit capacity of nuclear power units is also gradually increasing, with corresponding units ranging from 1000MW to 1700MW under construction or planning. The larger the unit capacity, the larger the number of low-pressure cylinders and the overall length of the steam turbine, which will greatly affect the overall efficiency of the steam turbine. Currently, the number of low-pressure cylinders and the overall length of the turbine can be reduced by increasing the length of the turbine's last-stage blades. [0003] The last-stage blade of a steam turbine is the core component of a steam turbine, especially for a large-capacity nuclear power steam turbine, which represents the technical level of a nuclear power...

AI Technical Summary

Problems solved by technology

[0004] In view of the shortcomings of the prior art described above, the purpose of the present invention is to provide a long blade at the end stage of a steam turbine to overcome the different back pressure and unit pressure requirements of CAP1400 / CAP1700 in the prior art due to the small exhaust area of ​​the blade at the end stage. Deficiencies in Class Nuclear Steam Turbine Application Requirements

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