| Supercritical, ultra supercritical steam turbine unit has a high thermal efficiency, low consumption, water consumption and low indicators. Compared with the sub-critical units, supercritical units to increase power generation efficiency of about 2-4%, ultra-supercritical power generation efficiency units can be increased by about 6%～7%.The development of ultra-supercritical units in the design and manufacture has many of the key technical issues to be resolved, the focus of future development of Ultra-supercritical emphasis in materials research and development and the temperature has increased. Supercritical units abroad early stages of development, high-temperature blade material is still used in traditional sub-critical unit leaf material. Benxi Steel starts researching from the fifties of the last century in China as early as the beginning of the turbine blade and bolt of steel production, the leaves gradually become China's steel production and development base, is a turbine blade of the traditional advantages of steel production enterprises. The market share of steel blades is always stable at 80%.Benxi Steel R & D Ultra-supercritical supercritical carbon steel blade equivalent Siemens, GE, Hitachi and Toshiba's advanced standards, design and control of the chemical constituents of a reasonable, uniform chemical composition, composition deviation small inclusions and the ferrite content is low, grain size small, low-quality good times, good mechanical properties, the indicators in line with technical standards, the level of overall quality of steel in the domestic leading level, reached the international advanced level, to replace imports to ensure that the "863" project, the state "use of the market for technology," a key construction project of the new export contracts of domestic leaf blade materials.In this paper, steel blades from the study of adverse environmental conditions start with the design of species composition of the various components of a comprehensive performance to consider the impact of performance requirements in accordance with smelting and reasonable control of Cr/C ratio, Nb/C ratio, the development of a reasonable scope of the standard components, combined with the variety of different technical quality, mechanical properties, the ferrite content of the request, work out the practical implementation of the control of the chemical composition to achieve the composition of the second design. By studying law with the return of Oxygen leaves ultra-low carbon steel smelting, and redissolving electroslag ingot production 3.0 tons, by the experiments of thermal processing technology to determine and optimize the design of the 800/650×4 mill pass system developed 3.0t large spindle-type electroslag ingot production supercritical, ultra supercritical new process steel blade; successful development of a mature and open fire blanks technology, the realization of a high alloy steel blade with rolled forging generation; study of a typical leaf of the internal quality of steel, Microstructure and mechanical properties of ferrite content and chemical composition and thermal history of the relationship; analysis of three typical steel blade defects, the process to develop the corresponding measures. |
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