What type of pump uses a reciprocating mechanism to move fluid?

The type of pump that uses a reciprocating mechanism to move fluid is a piston pump. Piston pumps operate by utilizing a piston within a cylinder, which moves back and forth to create a vacuum that draws fluid in and then pushes it out during its stroke. This positive displacement action is fundamental to the operation of piston pumps, making them effective in handling various fluids, including those with higher viscosities or those requiring specific precision in flow.

In contrast, gear pumps employ interlocking gears to create fluid movement through mechanical action, not a reciprocating mechanism. Centrifugal pumps use rotating impellers to generate flow, relying on centrifugal force rather than reciprocation. Roller pumps utilize rollers that rotate around a fixed axis, compressing a flexible tube to create suction and push fluid forward, again not embodying a reciprocating mechanism. Thus, the correct identification of piston pumps lies in their unique movement characteristics that distinguish them from other pump types.