Impeller closed type/shrouded

Both closed and open impellers have been widely used in centrifugal pumps handling slurries. Open impellers have some advantages when compared with closed ones. For instance, low manufacturing cost and low disc friction loss are considerable advantages of these impellers. Furthermore, they are suited for pumping suspensions. This types of impeller have only one shroud and are open on one side where a tip clearance takes place between open side of the impeller and the stationary casing as is seen in Fig. 1. 

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