Which of the following is a common type of hydraulic pump?

The gear pump is indeed a common type of hydraulic pump, widely used in various hydraulic systems due to its straightforward design and functionality. Gear pumps operate by using two gears that mesh together, effectively drawing fluid into the pump and pushing it out under pressure as the gears turn. This makes them particularly suitable for applications requiring a consistent and reliable flow of hydraulic fluid, as they can generate high pressures and maintain good efficiency.

Gear pumps are favored in hydraulic systems because they can handle a wide variety of fluids, including those with varying viscosities. Their ability to provide a smooth and continuous flow makes them ideal for applications in machinery, manufacturing, automotive, and more. The design simplicity also contributes to their durability and low maintenance requirements, which are critical factors in hydraulic system performance.

In contrast, the other pump types listed serve different functions or are oriented towards different applications. Vortex pumps and diaphragm pumps are typically not used as hydraulic pumps but are instead more common in fluid transfer situations or in applications where the handling of solids or varying fluid characteristics may be required. Pneumatic pumps operate on air pressure rather than hydraulic fluid, making them unsuitable for hydraulic power applications.