Rotary Gear Pumps

External Gear Pump have evolved into the simplest and most widely used type of rotary positive displacement pump. They generally feature two gears on separate shafts, with one shaft driven by a motor. The types of drive, sizes, and construction materials can vary significantly depending on the industry and specific application. External Gear Pumps offer flow rates ranging from 20 ml/min to over 50 L/min, and can handle pressures up to 500 bar.

Gear pumps are compact and straightforward, with few moving parts. Smaller external gear pumps can operate at speeds of up to 4000 rpm, enabling high flow rates within a compact design. They are also fully reversible, which supports complex hydraulic operations. Unlike centrifugal pumps, gear pumps are self-priming and capable of dry-lifting to considerable heights.

Because the output of external gear pumps is directly proportional to speed and provides a smooth, pulse-free flow, they are often used for metering, blending, and straightforward control feedback tasks. They can manage fluids with a wide range of viscosities, but it is important to consult pump engineers to ensure optimal pump performance. Gear pumps are also among the quietest types of positive displacement pumps, making them well-suited for applications where noise reduction is a priority.

Capacity: Up to 30 M3/HR

Size: 1/4″ X 1/4″ to 3″ X 3″ (6.35 mm to 75 mm)

Speed: Up to 4000 RPM

M.O.C: IS.210 FG 220 C.I. Grade

• Simple and Efficient Design
• Single Helical Gear Design
• Low Noise
• Easy to Maintain
• Optionally Available in Double Helical Gear Design

When the gears unmesh, the volume at the pump’s inlet increases. This expanded volume generates a vacuum, enabling external pressure to force fluid into the pump.

As the gears turn, fluid becomes trapped between the gear teeth and the casing’s cavity wall. This mechanism transfers the fluid from the pump’s inlet side to the outlet side. Tight clearances and high rotational speed help reduce internal fluid leakage in the reverse direction.

The extra fluid pushed to the outlet side, combined with the decreasing volume formed as the gears mesh, forces the fluid out through the outlet.