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.