某型燃气轮机封严盘的结构优化

为了分析研究某型燃气轮机封严盘均压孔裂纹故障，达到提高疲劳寿命的目的，进行了封严盘故障机理和局部结构修改分析.建立封严盘有限元分析模型，分析了封严盘振动应力分布特点和共振特性，结果表明:均压孔孔边应力水平高是疲劳裂纹的主要原因，针对该原因提出了改进方向.在装配状态下，针对原结构以及均压孔部位进行局部修改的几种情况进行了结构强度对比分析，最终提出了某型燃气轮机封严盘局部结构修改方案，修改后均压孔孔边的应力水平降低16%，屈服强度储备系数由0.891提高到1.069. 

Structure optimization of a certain type of gas turbine sealing disk

To systematically study the crack failure of the pressure-balanced holes on sealing disk,and increase the fatigue life of a certain type of gas turbine, failure phenomenon and local structural modification of sealing disk were analyzed. Finite element analysis model was established and the vibration stress distribution features and resonance characteristics were analyzed.From the analysis,it showed that the high static stress on edges of the pressure-balanced holes was the main cause of the fatigue crack and improvement measures were put forward.Structure strength comparison analysis were done based on the original structure and several local modifications to the pressure-balanced holes under assembly conditions,and finally the local structure modification scheme for sealing disk of a certain type of gas turbine was put forward. And then the stress on edges of the pressure-balanced holes reduced by 16%, the yield strength reserve coefficient increased from 0.891 to 1.069.