Under the condition of water with high sand content in pump station of ningxia-sea pumping project, the pump seal-ring is easily worn out. The oxy-acetylene flame spraying process was used to spray Ni-based self-fluxing alloy powder on the base of cast steel seal-ring for wear resistance experiment. The results show that, new seal-ring takes great advantages over the cast steel seal-ring in both resisting wear and cavitation and its life is over 2.75 times longer than that of the cast steel seal-ring.