Testing and Modification of an Axial Flow Irrigation Pump manufactured in Vietnam

The performance of a commonly used, inclined shaft, axial flow pump manufactured in Vietnam was evaluated . The pump tested had a 37 cm diameter thrust impeller and 40 cm outlet diameter. This pump was initially evaluated to establish the base performance curves for three total static heads of 1.45 m, 1.75m and 2.15 m at a constant recommended speed of 980 rpm. In the field survey, brass sleeve , impeller and lubricating system. These parts of the pump were modified and then it was tested again at the same test conditions used for the original one. Maximum efficiency of the original pump varied from 56.11% to 53.15% , and that of the modified pump from 57.63% to 54.52% when the total static head varied from 1.45 m to 2.15m . At these total static heads, the discharge, the total head and the power input varied from 387 to 347l/s, 4.25 to 4.60m and 28.72 to 29.38kW, respectively, for the original pump and from 388 to 346l/s , 4.29 to 4.63 m and 28.23 to 28.91 kw, respectivel , for the modified pump. The efficiency of the pump after modification increased by more than 1.5% and the power input decreased by 1.7%.