Abstract:The air purification system is the main component of the air source system of GKD2 diesel locomotive, which provides clean and efficient air source for the locomotive. However, there are defects in the structural design of the diesel locomotive air purification system, which lead to frequent failures of the locomotive brake system and running circuit, and seriously affect the safety of railway operation. According to the composition and working principle of the air purification system, combining with the practical application, this paper analyzes the causes of the failure, and takes relevant improvement measures to reduce the failure rate of the air purification system, which provides a reliable guarantee for the safe operation of locomotives.