What does positive displacement mean in a hydraulic pump?

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Multiple Choice

What does positive displacement mean in a hydraulic pump?

Positive displacement means the pump moves a fixed amount of fluid with every cycle. In other words, the volume displaced per revolution is constant. Because of that, the output flow rate is simply that fixed displacement multiplied by how fast the pump runs. If you increase speed, more fluid is moved per unit time; if you slow down, less. The system pressure can rise or fall based on the load, but the volume moved per revolution stays the same up to the pump’s limits. This is why a positive-displacement pump delivers a predictable, fixed volume per cycle, unlike other pump types where the volume moved can change with loading.

Positive displacement means the pump moves a fixed amount of fluid with every cycle. In other words, the volume displaced per revolution is constant. Because of that, the output flow rate is simply that fixed displacement multiplied by how fast the pump runs. If you increase speed, more fluid is moved per unit time; if you slow down, less. The system pressure can rise or fall based on the load, but the volume moved per revolution stays the same up to the pump’s limits. This is why a positive-displacement pump delivers a predictable, fixed volume per cycle, unlike other pump types where the volume moved can change with loading.

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