There are advantages and disadvantages of Open Impeller & Closed Impeller :- CLOSED OPEN IMPELLER IMPELLER The impeller Can to volute or compensate back for shaft clearance thermal must be growth, but if adjusted there is too when the much axial pump is at growth the operating vanes may temperature not line up and all axial exactly with thermal the discharge growth has nozzle. occurred
There are advantages and disadvantages of Open Impeller & Closed Impeller :- CLOSED IMPELLER OPEN IMPELLER Can compensate for shaft thermal growth, but if there is too much axial growth the vanes may not line up exactly with the discharge nozzle. The impeller to volute or back clearance must be adjusted when the pump is at operating temperature and all axial thermal growth has occurred