Abstract
In the process of running of the blast furnace top gas pressure recovery turbine, abnormal noise and vibration from the gas turbine engine were noticed. One blade was found fractured from the middle during the overhaul inspection of this machine after running. In order to avoid the similar accident from happening again, comprehensive inspections on the failed blade have been carried out with the mechanical property testing, metallographic structure observation, chemical composition analysis, macro-fracture and micro-fracture analysis, and energy spectrum analysis. The analytical results show that many spherical particles are noticed in the area of crack initiation, and these spherical particles are similar to the blade material in chemical composition. After a series of tests, it was thought that these spherical particles are the remnant of molten metal that was firstly cooled in the process of blade casting, and they became the vulnerable part in the blade. When the blade rotates at relatively high speed, the synthesis of centrifugal and aerodynamic stresses may cause the occurrence of stress concentration in the vulnerable part inside of blade, causing the initiation and propagation of crack and subsequently resulting in the blade fracture.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callMore From: DEStech Transactions on Materials Science and Engineering
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
