Advantages of External Gear Pumps:

1. Pressure & Flow: Commonly used in medium-pressure systems (approx. 100–200 bar) and suitable for high-flow applications.
2. Efficiency: Volumetric efficiency generally exceeds 90%.
3. Fluid Compatibility: Capable of handling highly viscous fluids.
4. Cost & Maintenance: Easy to maintain and highly cost-effective.

Points to Note:

1. Noise: Larger flow pulsation results in higher noise levels; long-term operation may require noise-control considerations.
2. Service Life: Prolonged high-speed or high-temperature operation increases wear and reduces lifespan.

Typical Applications

Widely used in agricultural machinery, industrial equipment, mobile machinery (such as forklifts and excavators), and lubrication systems.

Advantages of Internal Gear Pumps:

1. Pressure & Flow: Suitable for medium-high to high-pressure systems (200 bar or above) and high-flow requirements.
2. Efficiency:: Volumetric efficiency can reach above 93%. Equipped with radial and axial pressure compensation, slowing efficiency degradation over long-term operation.
3. Noise: Low flow pulsation (especially at high speeds), smooth output, and low noise—ideal for precision-control or noise-sensitive environments.
4. Durability: Radial and axial pressure compensation enhances adaptability to high pressure and high temperature, offering longer service life.
5. Multiple pumps can be assembled in series to meet flow rate requirements.

Points to Note

1. Cost & Maintenance:More complex structure requiring high-precision machining and assembly; therefore, cost is higher.

Typical Applications

Commonly used in manufacturing machinery, metal processing equipment, mobile machinery, hydraulic systems, servo systems, and electro-hydraulic integrated solutions. These applications usually require strict oil temperature control, high efficiency, and high precision—areas where internal gear pumps perform exceptionally well with their low noise and stable output.

CML – Professional Manufacturer of Internal & External Gear Pumps

CML has nearly 45 years of industry experience and a proven track record in developing and integrating both internal and external gear pump solutions. We are also the first manufacturer of internal gear pumps in Taiwan. Since 2001, CML has been the exclusive distributor for Eckerle in Asia, forming a long-term partnership that has strengthened our manufacturing capabilities and expanded our product portfolio.
For multi-stage pump configurations, CML professional team is authorized in assembly technology, enabling flexible combinations of imported Eckerle pumps and Taiwan-made pumps—balancing high efficiency, low noise, and cost-effectiveness.
CML offers a wide range of pressure and flow specifications, optimized based on different industries and equipment characteristics, supporting applications from high-pressure stable output to energy-efficient systems.