Rotary pump has two types of pumps: Rotary gear and which?

• A. Rotary vane
• B. Piston pump
• C. Gear pump
• D. Diaphragm pump

Answer: (A)

Rotary pumps move fluid by trapping it between rotating elements and the pump housing, creating sealed pockets that are carried from suction to discharge. The two main rotary families are gear pumps and vane pumps. In a gear pump, two intermeshing gears rotate to trap fluid between the gear teeth and the housing cavities, delivering it as the gears turn. In a vane pump, a rotor with sliding vanes creates moving chambers; as the rotor spins, the chambers expand and contract, drawing fluid in and pushing it out. Therefore, the other rotary pump type paired with gear pumps is the vane pump. Piston and diaphragm pumps use reciprocating motion rather than rotation, so they belong to different pump categories, and gear pump is already the other rotary type.