HPLPA/HPLPB Series High Pressure Gear Pump | HPLPA226 Replacement

Genlu Hydraulic proudly presents the HPLPA and HPLPB Series high-pressure external gear pumps, meticulously engineered as efficient power units for mobile construction machinery and demanding industrial hydraulic circuits. This series serves as a precise match for high-pressure standards, covering core models such as the HPLPA226, and specific engineering configurations like HPLPA226SMNG7G6BHY and HPLPB226SMNG6G6BAD. Acting as the heart of fluid transmission systems, Genlu guarantees 100% Drop-in Interchangeability in mounting flanges, SAE port specifications, drive shaft extensions, and geometric displacements. Backed by our uncompromising 100% Simulation Load Testing, every HPLPA/HPLPB gear pump is verified for volumetric efficiency and fatigue endurance under extreme pressure before dispatch, ensuring relentless and stable hydraulic power for your agricultural and construction equipment.

Technical Specifications 

• Product Series: HPLPA (Standard High-Pressure) / HPLPB (High-Pressure Heavy-Duty Variant)

• Representative Displacement: 22.6 cc/rev (HPLPA226 / HPLPB226)

• Rated Continuous Pressure: 250 bar (3625 psi)

• Max Intermittent Peak Pressure: 300 bar (4350 psi)

• Max Speed: 3000 rpm

• Min Operating Speed: 500 rpm

• Structural Configuration:

  • S (Shaft: Involute splined shaft)

  • M (Flange: SAE 2-bolt or 4-bolt)

  • NG7/G6 (Ports: Side-in/Rear-out or Side-in/Side-out)

• Housing Structure: High-tensile extruded aluminum alloy body with heavy-duty cast iron front/rear covers

• Rotation: Configurable as Clockwise (CW) or Counter-clockwise (CCW)

Key Technical Advantages:

• Enhanced Anti-Pressure Housing: Fabricated with high-tensile extruded aluminum bodies reinforced by heavy-duty cast iron covers, these pumps maintain geometric stability of gear mesh clearances even under extreme pressure loads, fundamentally minimizing volumetric efficiency decay caused by housing deformation.

• Full-Balance Floating Bushing Design: Internally fitted with precision pressure-balanced floating side plates. High-pressure system fluid is routed to the back of these bushings, dynamically compensating for axial clearances and maintaining volumetric efficiency above 94% under 250 bar+ continuous loads.

• High-Wear-Resistance Composite Bearings: Equipped with premium DU self-lubricating composite bearings, these provide exceptional radial load-bearing capacity and shock resistance. They ensure a stable oil film on bearing surfaces even during frequent startups and abrupt load fluctuations, preventing metallic scoring.

• Low-Pulsation Gear Machining: Gears are produced using precision CNC grinding processes. The high-overlap tooth profile design effectively dampens fluid discharge pulsations and hydraulic shocks, resulting in operational noise levels 3-5 dB lower than standard gear pumps, significantly improving operator environments.

Application Areas:

• Mobile Machinery: Multi-circuit hydraulic systems for agricultural tractors and combine harvesters.

• Construction Equipment: Primary implement pumps and steering assist systems for mini-excavators and skid steer loaders.

• Material Handling: Lifting systems for Aerial Work Platforms (AWP) and forklifts.

• Specialty Duty Vehicles: Rotary brush drive motors for refuse compactors and street sweepers.

Expert Maintenance Tips:

• Suction Vacuum Verification: High-pressure gear pumps are sensitive to suction restrictions. Ensure the suction line is unobstructed, and absolute vacuum does not exceed 0.8 bar. Fluid starvation causes severe cavitation, rapidly eroding gear end-faces and destroying internal bushings.

• Initial Startup Protocol: Pre-fill the pump casing with hydraulic oil before installation. Never operate at full speed under load during initial startup; jog the motor to bleed trapped air from the system before gradually engaging operational loads to ensure the hydrodynamic lubrication film is fully established.

• Fluid Cleanliness Management: Install return-line filtration with an absolute rating of at least 10μm. Maintaining fluid cleanliness at ISO 4406 19/17/14 significantly extends the operational life of precision internal components.