Axial Flow Check Valve Flow-Field Simulation and Failure Analysis at the Compressor Outlet of a Gas Compressor Station

In long-distance natural gas transmission, installing an axial flow check valve at the compressor outlet of a compressor station helps prevent backflow. Failure of this valve can cause compressor reverse rotation, which disrupts gas delivery. This study models and simulates the steady-state flow field at 100% valve opening and the transient flow features during valve opening and closing. In addition, a failed axial-flow check valve from a natural gas compressor station was disassembled, and initial observations of wear and deformation were used to verify the model. The results show that the maximum fluid velocity reaches 18.9 m/s at 100% valve opening, with a distinct vortex region forming in the throttling passage between the valve seat and disk. During valve opening, the inlet–outlet pressure difference decreases from 0.35 MPa at 0.001 s to 0.20 MPa at 0.080 s. At 60% relative opening, the maximum amplitude of the transient hydrodynamic force fluctuation reaches 662 N. During closure under a pressure difference of 300 kPa, the maximum disk velocity reaches 12.9 m/s. These transient flow and force characteristics, considered together with the wear observed on the guide sleeve and disk, provide insight into the delayed reseating of the valve.