Internal Eccentric Gear Pump

The simple “gear within gear” principle of Internal Eccentric Gear Pumps means that there are only 2 moving components within the process medium. The positive displacement is achieved by the filling of the cavities between the teeth of both the rotary and idler gears located in the pump head. With each revolution, a fixed volume of fluid enters the casing through the suction port, filling the space between the teeth of the gears. The crescent within the pump head then separates the fluid as the idler gear turns on the pump shaft.

Operating Principle of Yildiz Internal Eccentric Gear Pump

Image 1: Fluid entering the pump: The orange coloured section in the image represents the process medium as it is entering the pump suction port, pump casing & filling the cavities between the Idler Gear (Red) & Rotary Gear (Brown). The 3 arrows indicate the direction of fluid passage through the pump and rotational direction of the gears.

Image 2: Fluid filling the cavities & split of flow: As the fluid progresses through the pump head and fills the cavities between the gears it is also separated by the crescent shape in the pump head, which acts as a seal preventing backflow between the suction & discharge ports.

Image 3: Pump almost flooded: As the fluid fully fills the casing all cavities between the gears are completely filled in the form of locked pockets of fluid to guarantee absolute volume control and enable the pump to deliver a fixed volume per revolution.

Image 4: Pump is flooded & starts to discharge the process medium under pressure: Once the pump is fully flooded, the rotor and idler gears mesh together and form a liquid seal which is equidistant between the pump ports which then enables the fluid to exit the discharge of the pump under pressure. The delivery pressure is dependent on the installed power of the motor.