IPH Series Internal Gear Pump | Nachi IPH-22B IPH-45B IPH-66A Double Pump

The IPH Series high-pressure internal gear pumps (including single and double pump configurations like IPH-22B, IPH-45B, and IPH-66A) by Chengyuan Hydraulic are precision fluid power components fully compatible with Nachi (Fujikoshi) industrial standards. Featuring a unique radial and axial pressure compensation design, these pumps maintain exceptional volumetric efficiency even at pressures up to $30 \text{ MPa}$. The IPH series is the preferred choice for injection molding machines, precision presses, and industrial hydraulic stations due to its near-silent operation and long service life. Every IPH gear pump undergoes 100% simulated load testing at full pressure before shipment to ensure performance parity with the original, delivering guaranteed 100% original-place interchangeability.

Technical Specifications :

• Product Series: IPH High-Pressure Internal Gear Pump (Single/Double)

• Model Code Examples: IPH-22B-3.5-5-11 / IPH-45B-25-50-11 / IPH-66A-100-125-11

• Rated Operating Pressure: $25 \text{ MPa} (250 \text{ bar})$

• Peak Operating Pressure: Up to $30 \text{ MPa} (300 \text{ bar})$

• Displacement Range: $3.6 \text{ cm}^3/\text{rev}$ to $125.9 \text{ cm}^3/\text{rev}$

• Rated Speed Range: $600 \text{ – } 2000 \text{ rpm}$

• Volumetric Efficiency: $\ge 90\%$ (at $21 \text{ MPa}$)

• Noise Level: $60 \text{ – } 75 \text{ dB(A)}$ (dependent on size and pressure)

• Drive Shaft Options: Standard SAE splined or keyed shafts

• Configuration: Supports Double Pump or multiple combinations for multi-circuit flow output

Key Technical Advantages:

• Dual Radial & Axial Pressure Compensation: Utilizing specialized side-plate axial clearance and tip-seal radial compensation. As system pressure increases, the sealing plates automatically adjust, minimizing internal leakage and maintaining high volumetric efficiency during high-pressure cycles.

• Superior Ultra-Low Noise Profile: The internal gears feature a special involute short-tooth profile with high overlap coefficients and minimal pulsation. Compared to external gear or vane pumps of similar displacement, operational noise is reduced by $10 \text{ – } 15 \text{ dB}$, significantly improving the working environment.

• Extended Service Life via Internal Gearing: The inner and outer gears rotate in the same direction with very low relative sliding velocity. This structure dramatically reduces tooth wear and heat generation, which, combined with high-performance bushings, provides a service life far exceeding standard gear pumps.

• Modular Double-Pump Capability: Models like IPH-45B allow for the integration of different pump sizes through direct coupling. This modular design saves space and allows a single motor to drive multiple independent circuits, reducing overall system costs for the OEM.

Application Areas:

• Precision Machinery: Servo-controlled injection molding machines, CNC machine tools, and hydraulic presses.

• Heavy-Duty Systems: Rubber processing machinery, metal shears, and waste balers.

• Testing Rigs: Laboratory hydraulic power units and fatigue test benches.

Expert Maintenance Tips:

• Strict Fluid Cleanliness Control: Internal gear pumps are sensitive to hard particles. Maintain a system filtration rating of $10 \mu\text{m}$ or better (ISO 4406 18/16/13) to protect precision compensation components.

• Prevent Aeration/Cavitation: Ensure the pump housing is filled with oil before startup and that the inlet line is perfectly sealed. Aeration-induced cavitation will damage gear teeth and cause a sharp increase in noise.

• Housing Air Bleeding: After the initial installation, use the bleed plug on top of the pump housing to exhaust air, ensuring the bearings and seals are immediately and fully lubricated.