Research & Development Information
Activities of R&D Center
Power System Maintenance
Hydropower Plants, Transmission lines and Substations
We focus on advanced technologies for preventing accidents of equipment, prolonging the life, and remaining life assessment on hydropower, transmission and substation equipment in particular. For example, we have been developing the following technologies;
- Frictional wear estimation of the runner blades of hydroelectric turbines
- Reduction of accidents by lightning, snow accretion or bird-related problem on overhead transmission lines
- Estimation of remaining service life by imposed electrical tests on underground power cables
Test facility of overhead line
Snow accretion on overhead ground wire
400kV AC test facility for power cable
Thermal Power Plants
We are conducting R&D on the following themes;
- Analysis of high temperature corrosion and wear damage on furnace water walls in pulverized coal firing boilers
- Creep and fatigue damage evaluation of steam turbine castings
- Life assessment of gas turbine hot parts
- c-1. Analysis of high temperature degradation of gas turbine hot parts
- c-2. Analysis of fatigue crack propagation in advanced gas turbine blades and nozzles
We are focusing on the theme c-2 in particular.
Blades and nozzles of gas turbine power plants are exposed to high temperature combustion gas during operation. In order to decrease temperature of a substrate, they are air-cooled internally. Thermal barrier and corrosion-resistant coatings are often sprayed on the outer surface. Though these treatments decrease substrate temperature and reduce damage efficiently, low ductility of coatings at relatively low temperature and thermal stress due to internal air-cooling sometimes causes coating cracks.
Directionally solidified Ni-based superalloys are used for blade applications at new 1500°C class gas turbine power plants. Crystal orientation may affect crack propagation behavior in this type of superalloy. If we can evaluate the effect, we can make an adequate run-repair-replace criterion and reduce maintenance costs of these expensive components.
Simulated temperature distribution and thermal deformation of a gas turbine nozzle
Scanning electron microscopy (SEM) and microstructure of Ni-based superalloy