Abstract: This paper introduces the main configuration form and basic parameters of the main air blower set and the actual operating parameters of the flue gas turbine in a Qingdao refinery adopting MIP-CGP process in catalytic cracking unit.It makes an in-depth analysis on the steam overrun of flue gas turbine disc cooling.The paper discovered the root causes for the change of steam parameters.During the device operation,the influencing factors for disc cooling steam are verified by way of setting modification methods such as changing the steam temperature under the premise of ensuring the safety.Then,the final technological revamp scheme is presented.