TOP-204HB TOP-206HB TOP-212HB TOP-220HB Lubricating Gear Pump | NOP Replacement

Genlu Hydraulic proudly introduces our TOP-2HB Series high-performance industrial-grade internal gerotor lubricating gear oil pumps. Specifically engineered to sustain stable fluid transfer and continuous high-pressure flow rates across critical machine tool spindles, heavy industrial gearboxes, turbine aggregates, and centralized lubrication systems, this line serves as a precision-manufactured, drop-in replacement for the classic NOP (Nippon Oil Pump) TOP-2HB product architecture. We specialize in cross-referencing and supplying the complete configuration spectrum, including TOP-204HB, TOP-206HB, TOP-208HB, TOP-210HB, TOP-212HB, and high-volume variants TOP-216HB and TOP-220HB.

Serving as the fluid circulation core for critical mechanical components, the TOP-2HB series capitalizes on an optimized internal Trochoid Gear design. Genlu’s replacement gear pumps conform strictly to global dimensional templates and fluid-dynamic metrics. We guarantee 100% Drop-in Interchangeability across standard mounting pilot diameters, input shaft geometries, threaded oil ports, and internal pressure safety relief valve (VB types) adjustment tracking curves. Every single production unit is subjected to 100% high-temperature pressure running-in, vacuum intake validation, and cross-port micro-leakage analysis, ensuring zero mechanical deadheads and long-term deployment integrity under severe continuous duties.

Technical Specifications 

• Product Line: TOP-2HB Series High-Pressure Internal Trochoid Gear Lubrication Pump

• Core Covered Model Configurations: TOP-204HB, TOP-206HB, TOP-208HB, TOP-210HB, TOP-212HB, TOP-216HB, TOP-220HB

• Theoretical Displacement Values:

  • TOP-204HB Variant: 4.0 $cc/rev$

  • TOP-206HB Variant: 6.0 $cc/rev$

  • TOP-208HB Variant: 8.0 $cc/rev$

  • TOP-210HB Variant: 10.0 $cc/rev$

  • TOP-212HB Variant: 11.6 $cc/rev$

  • TOP-216HB Variant: 15.6 $cc/rev$

  • TOP-220HB Variant: 19.6 $cc/rev$

• Maximum Rated Working Pressure: 2.5 MPa (25 bar)

• Maximum Permissible Shaft Speed: 2500 rpm (Optimized for standard 1500 rpm / 1800 rpm industrial motor direct coupling)

• Theoretical Flow Output (@ 1500 rpm Base):

  • TOP-204HB Configuration: 6.0 L/min

  • TOP-206HB Configuration: 9.0 L/min

  • TOP-212HB Configuration: 17.4 L/min

  • TOP-220HB Configuration: 29.4 L/min

• Overload Protection Configuration: Fixed displacement pump; available with an optional integrated safety relief valve module (VB type) to manage dynamic circuit over-pressurization

• Allowable Fluid Viscosity Spectrum: 10 – 500 $mm^2/s$ (Fully compatible with light lubricating oils, turbine fluids, and heavy motor oils)

• Target Volumetric Efficiency Boundary: $\ge 92\%$ under full rated pressure and speed conditions

Key Technical Advantages:

• Trochoid Profile Design with Ultra-Low Flow Ripples: The internal gerotor configuration features co-axial internal-meshing rotors. Because the dynamic sealing line remains perfectly continuous and smooth, chamber volume scaling is exceptionally uniform. This translates to a 70% reduction in discharge flow ripples compared to external gear configurations, eliminating spindle vibration caused by fluid spikes.

• Anti-Friction Alloy Cast Iron Matrix with Lapped End Faces: The main casing and rotor set are molded from premium wear-resistant cast iron subjected to extensive stabilization tempering. End faces are finished using advanced double-disc lapping machinery to micron tolerances. This provides high volumetric output and robust resistance to high-viscosity fluid shearing during cold machinery restarts.

• Cavitation-Suppressed Low-Noise Internal Fluid Routing: The internal suction ports are geometrically maximized via CFD analysis to minimize inlet vacuum restrictions. This feature prevents fluid cracking and aeration bubbles when pulling high-viscosity gear lubricants, maintaining aggregate acoustic emissions at a quiet $\le 55$ dB(A).

• Upgraded Journal Bearing Support & Premium Shaft Seals: Equipped with reinforced dual-metal hydrodynamic sleeve bearings paired with a high-durability Viton double-lip shaft seal. This arrangement withstands continuous thermal loads up to 130°C while damping high-frequency micro-vibrations from the prime mover, ensuring dry shaft extensions over extensive operations.

Application Areas:

• Precision CNC Machine Tools: Forced lubrication, gear cooling, and headstock conditioning for CNC machining centers, high-speed lathes, and large gantry milling assemblies.

• Heavy Industrial Gearboxes: High-volume lubrication systems for wind turbine gearboxes, primary metallurgical rolling mill reducers, and cement kiln hydrodynamic bearing stations.

• Primary Power Equipment: Pre-lubrication booster pumps for large marine diesel engines, steam turbine lube manifolds, and heavy-duty process compressor crankshaft loops.

Expert Maintenance Tips:

• Mandatory Pre-Commissioning Fluid Cavity Priming: Internal gerotor architectures utilize the working fluid itself to lubricate their internal sliding bearing boundaries. Prior to initially engaging the electric drive motor, YOU MUST pre-fill the pump interior with clean oil through the ports. Never crank the pump dry; dry running will score rotor faces and seize the components within seconds.

• Strictly Verify Motor Rotational Alignment: The standard single TOP-2HB element possesses a fixed rotational constraint (typically Clockwise / Right-Hand viewed from the shaft end unless specified). Incorrect motor wiring will reverse the intake and discharge ports, starving the machine of oil pressure and risking pump body rupture due to safety valve bypass blockages.

• Implement Proper Intake Strainer Discipline: Recirculated lubrication oil often transports fine abrasive metallic fines. The suction plumbing line must be equipped with a mesh strainer rated at 150 mesh or coarser to prevent larger debris aggregates from scoring the trocho-转子 profiles. If pressure gauges oscillate erratically, halt operation immediately to flush the strainer basket and prevent cavitation.