Evaluation of corrosion fatigue crack propagation life at low-pressure steam turbine rotor groove |
| |
Authors: | Akira Morita Hiroyuki Kagawa |
| |
Affiliation: | a Power Engineering R&D Center, The Kansai Electric Power Co. Inc., 11-20, Nakoji 3-chome, Amagasaki, Hyogo 661-0974, Japan b Design Engineering Group, Engineering Center, Fossil Power Division, The Kansai Electric Power Co. Inc., Dai Building, Room 470, 6-32, Nakanoshima 3-chome, Kita-ku, Osaka 530-6591, Japan c Graduate School of Engineering, Kyushu University 6-10-1, Hakozaki, Higashi-ku, Fukuoka 812-8581, Japan d Graduate School of Engineering, Osaka University 2-1, Yamadaoka, Suita, Osaka 565-0871, Japan |
| |
Abstract: | The corrosion fatigue crack propagation life of Christmas-tree type rotor groove with three hooks is studied. Each corner of the hook can be a candidate for crack initiation site therefore the condition where cracks initiate and propagate simultaneously at several hook corners must be considered. When a blade is inserted in the rotor groove, narrow gap is introduced unavoidably between the rotor groove and the blade root. The effect of this narrow gap on the crack behavior must also be considered. A procedure was presented to assess the crack initiation and propagation behavior under such a condition. Using the procedure, crack initiation and propagation behavior was evaluated for several gap conditions. It was revealed that the gap condition had little effect on the relation between crack depth at the third hook corner and life consumption ratio (ratio of loading cycle to final failure life). A corrosion fatigue test was performed using a rotor groove model specimen, and the results were compared with the evaluation results. |
| |
Keywords: | Life prediction Finite element method Crack propagation Corrosion fatigue Turbine rotor Rotor groove Hot water Life consumption rate |
本文献已被 ScienceDirect 等数据库收录! |
|