An internal gear pump uses two gears of different sizes rotating inside a common casing: a larger outer ring gear with internal teeth and a smaller inner gear with external teeth that meshes inside it. As the gears rotate, the unmeshed side creates an expanding cavity that draws liquid in, carries it around the casing between the gear teeth and casing wall, then pushes it out as the gears mesh again on the discharge side.
This positive displacement action delivers a steady, metered flow at a rate directly proportional to shaft speed. That makes IGX suitable for controlled oil transfer, oil burner service, force-feed lubrication, and hydraulic oil pressure duty where delivery must remain stable as pressure changes.
Centrifugal pumps lose flow as system back pressure increases. The IGX positive displacement action maintains a consistent delivery rate regardless of pressure, which is essential for oil burner service and force-feed lubrication systems where metered oil delivery is critical.
The internal gear principle is well suited for viscous oils because the gear and casing clearances seal effectively with higher viscosity liquids. Capacity is specified at 1440 RPM, so viscosity and temperature must be confirmed for accurate duty sizing.
The IGX includes a built-in pressure relief valve that limits system pressure and protects the pump, pipework, and connected equipment from over-pressure. External bypass arrangement is also available for relevant system configurations.