By changing the shape of blade suction port, although the efficiency of large flow is reduced, the anti cavitation performance of dredging pump is significantly improved.

impeller outlet widths (such as are selected for sewage or dredge pumps) o drops as. Small NPSH is as important as stable operation at the critical cavitation point. This value depends on the impeller geometry or the specific speed. The phenomenon of sudden drop of head in cavitation test is analyzed, and the harm of this phenomenon to the slurry transported in the process of dredging is pointed out. The invention provides a casting process of a large dredge pump impeller, belonging to the technical field of casting metallurgy, and comprising the following steps: establishing casting process parameters and pouring parameters, CAE simulation, manufacturing a model and a sand mold, pouring, pressing a box, boxing, cleaning, heat treatment and vibration aging. The difference of NPSHr is up to 0.8m near the design flow rate. For the cavitation performance, the shape of the suction port of the blade has a great influence on the NPSHr of the pump. As producer of slurry pumps with casting foundry shop, Muyuan can offer many kinds of pump impellers, such as the colsed type or the open type slurry pump. When the flow rate is less than the design flow rate, the shape of the inlet edge of the three blades has little influence on the external characteristics when the flow rate is greater than the design flow rate, the shape of the suction port of the blade has a significant influence on the pump head and efficiency. The external characteristics and cavitation performance tests were carried out on a high-precision open test bench, and the effects of three kinds of blade inlet edge shape on the performance of the model pump were compared and analyzed. The model pump was made according to the proportion of 1:2. MG dredge pumps are constructed of a single casing connected by means of clamps and a widened suction port.Aiming at the impeller of trailing suction dredger, on the premise of the same impeller dimensions, three kinds of twisted blades with inlet edge shape were designed. MG Gravel pumps are designed for the continuous handling of the most difficult higher abrasive slurries, containing solids too large to be pumped by a standard slurry pump. MG Dredge pump are designed to handle very large particles for gravel and dredging operations. An analytic method for designing blades of the impeller of an axial dredge pump is developed.

Dredge pump impeller