Yuan Hydraulic CB-KP63/20 Double Gear Pump

Yuan Hydraulic CB-KP63/20 Hydraulic Double Gear Pump (20 MPa / 200 Bar) – High-Pressure Tandem Unit

The Yuan Hydraulic CB-KP63/20 is a dual-stage, external tandem gear pump built for dual-circuit, medium-to-high pressure industrial, offshore, and marine hydraulic applications. Manufactured with high-tensile nodular cast iron end-covers and a rigid, extruded high-integrity pump body, the unit integrates two independent pumping sections driven by a continuous high-torque common drive shaft.

The primary stage delivers a nominal displacement of 63 cc/rev, while the secondary auxiliary stage delivers 20 cc/rev. Both sections are engineered for a nominal continuous operating pressure of 20 MPa (200 bar / ~2,900 psi) with peak dynamic surge ratings up to 25 MPa (250 bar / ~3,625 psi). Internal hydraulic efficiency is maintained by dynamic axial pressure-compensation thrust plates, low-friction bronze journal bushings, and anti-extrusion back-up seals that minimize volumetric blow-by during heavy thermal and mechanical cycles.

Model Details:

• Manufacturer / Brand: Yuan Hydraulic
• Model Identifier: CB-KP63/20 (Variants include: CB-KP63/20-B5F4P3, CB-KP63/20-F)
• Manufacturer Part Number (MPN): YHN-CBKP63-20-200B
• Condition: New Unused Surplus

Pump Features

1. Dual-Stage Independent Flow Isolation: Configured with a 63 cc/rev front element for main actuators and a 20 cc/rev rear element for pilot controls, steering, or auxiliary cooling, operating on a unified input shaft without inter-stage fluid cross-contamination.
2. Dynamic Axial Clearance Compensation: Floating wear plates utilize internal discharge pressure balance to self-adjust axial running clearances, maintaining volumetric efficiency above 93% even at maximum working pressure.
3. High Dynamic Fatigue Resistance: Liquid extrusion alloy/ductile casing dampens pressure ripples and withstands sustained structural vibrations encountered in marine power packs, winches, and mobile machinery.
4. Heavy-Duty Hydrodynamic Journal Bearings: High-load needle/roller bearing arrangements resist radial and axial side loads typically transmitted through direct PTO spline or bell-housing drives.
5. Standardized High-Pressure Porting: Split-flange SAE / metric 4-bolt connection ports eliminate thread shearing and fluid bypass under continuous 200 bar cyclical loads.

Technical Details:

Part Number Cross-References

• Direct Match: Yuan Hydraulic CB-KP63/20, CBKP63/20-B5F4P3
• Equivalent Tandem Families: CBHC-2063/20, CBZTG, G20/G10 Double Units, Casappa Kappa 30/20 Dual-Series equivalent displacements

Frequently Asked Questions

What does the CB-KP63/20 designation indicate?

CB” designates an external hydraulic gear pump series, “KP” refers to the high-pressure structural rating, “63” represents a primary pump displacement of 63 cm³/revolution, and “20” represents the secondary pump displacement of 20 cm³/revolution.

Can the front and rear pump sections operate at different working pressures?

Yes. The 63 cc/rev and 20 cc/rev stages feature isolated discharge paths. While both sections are rated to 20 MPa continuous pressure, they can feed two completely independent hydraulic circuits with differing working loads without interfering with each other’s pressure stability.

What is the maximum continuous working pressure for this unit?

The standard continuous rated pressure is 20 MPa (200 bar / 2,900 psi), with peak instantaneous relief spikes accommodated up to 25 MPa (250 bar / 3,625 psi).

How do I verify the correct direction of rotation before installation?

Rotation is defined looking directly at the pump drive shaft face: Clockwise (Right / R) or Counter-Clockwise (Left / L). Connecting reverse rotational drive to a uni-directional gear pump will over-pressurize the shaft seal and immediately rupture the internal low-pressure containment barriers. Confirm your prime mover rotation before fitting.

What hydraulic fluid viscosity should be used with the CB-KP63/20?

The optimal viscosity range during continuous operation is 20 to 100 cSt (mm²/s), typical of ISO VG 46 or ISO VG 68 mineral anti-wear hydraulic oils. Cold starts should not exceed 1,000 cSt, and fluid cleanliness should be maintained at or above ISO 4406 Class 19/17/14.