Rank the following types of pumps from lowest to highest pressure:

To rank the types of pumps from lowest to highest pressure, it's essential to understand the operating principles and capabilities of each pump type.

Centrifugal pumps operate by converting rotational energy into fluid movement. They are designed primarily for high flow rates rather than high pressure, making them effective for applications that do not require significant pressure elevation. Hence, they typically yield lower pressure than the other types of pumps listed.

Roller pumps, which are positive displacement pumps, use rollers to compress the fluid and push it through the system. They are more effective at producing moderate pressures compared to centrifugal pumps but are still generally limited compared to piston pumps.

Piston pumps utilize a reciprocating piston mechanism to generate high pressures. They excel in applications where significant pressure is required to move the fluid. Piston pumps can deliver much higher pressure outputs compared to both centrifugal and roller pumps.

Considering these characteristics, it is clear that the correct order from lowest to highest pressure is indeed centrifugal pumps, followed by roller pumps, and finally piston pumps. This classification reflects their capabilities in terms of pressure generation effectively.