Single suction pumps use which types of impellers?

Single suction pumps use which types of impellers?

• A. All of the above
• B. Open
• C. Semi-Open
• D. Closed

Answer: (A)

Single-suction pumps are defined by how the fluid enters the impeller, not by the impeller’s shape. In practice, the impeller can be open, semi-open, or closed in a single-suction pump. Open impellers have no back shroud, which makes them good for passing solids and easier maintenance in dirty liquids, though they tend to have lower efficiency. Closed impellers are fully enclosed by a back disc on both sides, giving higher hydraulic efficiency and better performance with clean liquids. Semi-open impellers sit between, offering a compromise of solid-handling capability and efficiency. Because service conditions—such as solids content, wear, and efficiency targets—drive the choice, a single-suction pump may use any of these impeller types. So, all three impeller designs are applicable to single-suction pumps.

Single-suction pumps are defined by how the fluid enters the impeller, not by the impeller’s shape. In practice, the impeller can be open, semi-open, or closed in a single-suction pump. Open impellers have no back shroud, which makes them good for passing solids and easier maintenance in dirty liquids, though they tend to have lower efficiency. Closed impellers are fully enclosed by a back disc on both sides, giving higher hydraulic efficiency and better performance with clean liquids. Semi-open impellers sit between, offering a compromise of solid-handling capability and efficiency. Because service conditions—such as solids content, wear, and efficiency targets—drive the choice, a single-suction pump may use any of these impeller types. So, all three impeller designs are applicable to single-suction pumps.