CBQL Series Double Gear Pump | CBQL-F540/532-CFH | High Pressure

Genlu Hydraulic is proud to offer the CBQL Series and its derivatives, heavy-duty high-pressure tandem (double) external gear pumps. These multi-circuit fluid power cores are meticulously engineered for complex mobile machinery—such as forklifts, wheel loaders, and agricultural tractors—that require independent hydraulic flow to simultaneous functions. This series accurately covers highly demanded large-displacement configurations like the CBQL-F540/532-CFH, CBQL-F540/F540, and CBQL-F532/F520, while smoothly facilitating system upgrades for standard CBF, CBG, and CBK installations. Serving as the dual-circuit powerhouse of your machinery, Genlu guarantees 100% Drop-in Interchangeability in mounting flanges, drive shafts, the shared suction port, and dual discharge ports to meet the highest industry standards. Supported by our rigorous 100% Simulation Load Testing, every single CBQL double gear pump passes extreme peak-pressure validations for volumetric efficiency and inter-stage cavity seal integrity. This ensures your multi-way directional valves and hydrostatic steering units receive relentless, interference-free power.

Technical Specifications 

• Product Series: CBQL-F5 Series High-Pressure Double External Gear Pump

• Representative Geometric Displacements:

  • CBQL-F540/532: Front pump 40.0 cc/rev, Rear pump 32.0 cc/rev

  • CBQL-F540/F540: Front pump 40.0 cc/rev, Rear pump 40.0 cc/rev (Equal displacement)

  • CBQL-F532/F520: Front pump 32.0 cc/rev, Rear pump 20.0 cc/rev

• Rated Operating Pressure: 20 MPa (200 bar / 2900 psi)

• Max Peak Pressure: 25 MPa (250 bar / 3625 psi)

• Rated Speed: 2000 rpm

• Max Operating Speed: 2500 rpm

• Structural Configuration: C (Standard keyed or splined shaft), F (Square/Rhombus flange), H (Flanged or threaded ports)

• Housing Material: High-tensile extruded aluminum alloy bodies mated with impact-resistant cast iron end covers and center intermediate plates

Key Technical Advantages:

• Compact Dual-Circuit Architecture: Utilizing a single drive shaft to power two independent pump cartridges in a tandem setup. The larger front pump typically drives primary working implements (e.g., lift cylinders), while the smaller rear pump supplies the hydrostatic steering. A shared ultra-large suction port dramatically simplifies machine plumbing and conserves installation space.

• High-Tensile Extruded Aluminum Housing: Both the front and rear pump bodies are crafted from specialized, high-density extruded aluminum profiles. This not only significantly reduces the tandem pump’s overall weight but also imparts exceptional thermal dissipation, preventing efficiency degradation during prolonged heavy-load operations.

• Intelligent Axial Clearance Compensation: Each pump cartridge is equipped with precision floating bushings. By routing high-pressure system fluid to the rear of these bushings, axial clearances are dynamically compensated in real-time according to load. This sustains volumetric efficiency above 92% across both stages, even under continuous 20 MPa pressures.

• Reinforced Tandem Coupling & Bearings: The connection between the front and rear cartridges features an induction-hardened, high-torsion rigid coupling, absorbing severe torque spikes during sudden load shifts. Internally, heavy-duty DU self-lubricating composite bearings are utilized, vastly improving resistance to radial wear.

Application Areas:

• Material Handling Equipment: Primary lift circuits and independent power steering circuits for IC (Internal Combustion) and large-tonnage electric forklifts.

• Earthmoving & Construction: Working implement hydraulics and pilot control supply for compact and medium wheel loaders.

• Agricultural Machinery: Multi-way valve power take-offs and hydraulic hitch mechanisms for high-horsepower tractors.

• Specialty Duty Vehicles: Coordinated multi-actuator systems for refuse compactors and street sweepers.

Expert Maintenance Tips:

• Shared Suction Port Sizing Limitations: The CBQL tandem pump relies on a single, oversized suction inlet to feed both the front and rear stages simultaneously. It is critical to ensure the suction line inner diameter is massive and unrestrictive. Suction vacuum must never exceed 0.08 bar; otherwise, “fluid starvation” will cause catastrophic cavitation and high-pitch whining, rapidly destroying the rear pump stage.

• Strict Coaxial Alignment: Due to the extended physical length and large rotor span of a tandem pump, the alignment (coaxiality) of the coupling to the engine PTO or electric motor must be maintained within 0.05 mm. Misalignment induces severe off-center loading, leading to rapid front bearing failure and shaft seal blowouts.

• Fluid Temperature Management: Keep the hydraulic system fluid operating between 35°C and 60°C. During cold winter starts, never throttle up the engine under load immediately. Jog the pump at idle with zero load for several minutes to allow the hydrodynamic lubricating film to properly establish within the composite bearings.