增压锅炉汽包低周疲劳寿命计算方法研究

Study of the Methods for Calculating the Low-cycle Fatigue Life of a Supercharged Boiler Drum

在分析、比较和论证美英德和我国同类标准计算方法的基础上,确定了计算载荷的种类、考核点的位置,选取了应力集中系数和低周疲劳设计曲线,确定了主应力差计算的强度准则和疲劳损伤安全准则的计算方法,建立了径向温差及其热应力的计算方法、内压应力和径向温差热应力的合成方法,并形成了满足蒸汽动力装置机动性要求的增压锅炉汽包低周疲劳寿命计算方法。方法的建立,不仅对增压锅炉汽包的设计工作具有指导作用,而且为最终确立增压锅炉汽包低周疲劳寿命计算方法及其相关问题的拓展性研究奠定了基础。

On the basis of an analysis, comparison and argumentation of USA, Great Britain and German standard calculation methods as well as our country's same calculation ones, determined was the variety of calculation loads and the location of the examination and check points, and chosen were a stress concentration coefficient and the low-cycle fatigue design curve. In addition, the strength criterion for calculating the main stress difference and the method for calculating the fatigue and damage safety criterion were determined. The method for calculating the radial temperature difference and its thermal stress as well as the method for synthesizing the inner pressure stress and radial temperature difference-caused thermal stress were established. On this basis, the method for calculating the low-cycle fatigue life of a supercharged boiler drum was determined to meet the maneuverability requirements for steam power plants. The establishment of the method in question can not only offer guidance for the design of supercharged boiler drums, but also lay a foundation for the exploratory study concerning the final determination of the method for calculating the low-cycle fatigue life of supercharged boiler drums and other relevant problems.