NBZ5 NBZ4 Internal Gear Pump | NBZ5-G125F NBZ4-C100F | Low Noise High Pressure

The NBZ Series Internal Gear Pump (specifically NBZ4 and NBZ5) from LIC Hydraulic is the premier solution for applications requiring high pressure and whisper-quiet operation. Utilizing advanced internal gearing and a compensated “crescent” design, these pumps eliminate the pulsation and noise associated with traditional external gear technology. Models like the NBZ5-G125F and NBZ4-C100F are widely used in high-end servo-driven hydraulic systems. We provide 100% drop-in replacements that match original OEM specifications for mounting, shafts, and performance curves.

Technical Highlights

• Frame Sizes: NBZ4, NBZ5.

• Displacement Range: $80\text{ cc/rev}$, $100\text{ cc/rev}$, $125\text{ cc/rev}$.

• Max Pressure: Continuous duty up to $250\text{ bar}$ ($3625\text{ psi}$); Peak up to $315\text{ bar}$.

• Speed Range: $400\text{ to }3000\text{ rpm}$ (optimized for servo motor cycles).

Core Advantages

• Ultra-Low Noise Profile: The internal gearing design dampens fluid vibration. In a standard factory environment, the NBZ series is significantly quieter than piston or external gear pumps, improving the workplace environment.

• High Efficiency at Low Speeds: Thanks to the dual axial and radial gap compensation, the NBZ5 series maintains high volumetric efficiency even during long-duration pressure-holding cycles at low RPMs, saving significant energy.

• Rugged Reliability: Built with hardened internal components and low-friction bearings, these pumps are engineered to withstand millions of cycles in high-pressure pressing and injection molding applications.

• Minimal Flow Pulsation: The smooth engagement of the internal teeth reduces pressure spikes, extending the life of your hydraulic hoses, fittings, and sensitive control valves.

Expert Maintenance Tips

• Oil Cleanliness: To protect the precision-lapped crescent plate, maintain oil cleanliness at ISO 18/16/13. Particle contamination is the primary cause of internal leakage in gear pumps.

• Inlet Sizing: Given the high displacement of the NBZ5-G125F, ensure the suction line is correctly sized. A restricted inlet will cause cavitation and rapid wear of the internal gears.

• Cold Starts: In cold climates, allow a brief warm-up period at low RPM to ensure the internal compensation plates are fully lubricated before applying maximum system pressure.