Rotary Gear pumps are commonly used as priming pumps. (True or False)

• A. A True
• B. B False
• C. C Not used
• D. D Sometimes in some cases

Answer: (A)

Rotary gear pumps lend themselves well to priming because they are positive-displacement devices that can pull water through the suction line and establish a prime with a steady, controllable flow. Their design traps a fixed volume of water between the gears and the casing, so as the gears rotate, water is drawn in and then pushed toward the main pump. This creates a strong vacuum on the suction side, which helps expel air and fill the pump with water. The arrangement is compact, rugged, and can operate effectively at the low speeds typical of priming operations, making it a dependable choice for getting the main pump ready to generate discharge pressure. In practice, many fire apparatus use a gear-type primer specifically for this priming task, which is why the statement is considered true.