In order to solve the problems of blockage pump and harrow,which seriously affect the construction and production in Blank Project in Russia,we study the passage capacity of the dredge pump and the grating of the rake head.Based on the similarity principle of mud pump,we analyze the aspects such as the size increase of spherical channel of mud pump,the influence of impeller cutting on the performance of mud pump,blade cutting length calculation,impeller cutting operation,and adjust impeller diameter of mud pump to suit complex working conditions of multi-rock sediment.Through the methods,the low construction efficiency of the small flow impeller under the multi-rock sediment is solved,the volume of passing pump of single ship increases 44% averagely,the loading productivity increases 17% averagely,and the cycle productivity increases 11.5%.