Aiming at the problems of high consumption, low exit velocity and low sweeping efficiency of the spray nozzle for cleaning excess zinc particles in galvanized steel pipe in workshop, a new type of inner blowing ring structure was designed. The structure consisted of four nozzles, each of which had a B-spline curve and the outlet of the spray nozzle had an elliptical structure. The flow field simulation of the original inner blowing ring and the new inner blowing ring shows that the sweeping effect of the new inner blowing ring is higher than that of the original inner blowing ring. The influence of the distance between the outlet of the inner blowing ring and the nozzle orifice, the pressure of the nozzle and the diameter of the nozzle outlet on the flow field was also studied. The results show that the sweeping effect of 40 mm target distance is better than that of 20 mm and 30 mm; when the pressure of inner blowing ring is 0.6 MPa, the jet velocity is greater than that of 0.3 and 0.15 MPa; the smaller the exit cross-section area, the higher the sweeping efficiency.