If the crescent seal in an internal gear pump becomes worn, what happens to the flow inside the pump?

When the crescent seal in an internal gear pump becomes worn, the flow dynamics within the pump are significantly affected. The crescent seal plays a crucial role in maintaining pressurization and directing fluid flow between the gears. A worn crescent seal can result in a loss of efficiency, causing some of the discharge flow to recirculate back to the inlet.

This recirculation occurs because the integrity of the seal is compromised, allowing the fluid that was meant to be pushed out through the discharge port to leak back into the pump's inlet. Consequently, this reduces the effective output flow from the pump, leading to a diminished performance overall. While some flow will still move through the pump, the presence of recirculation indicates that not all of the intended discharge flow is being delivered to the system as required.

Understanding this concept is essential for diagnosing issues in hydraulic systems and emphasizes the importance of maintaining pump components to ensure efficient operation.