CBK-F8 Hydraulic Gear Pump 8.08 ml/r 20MPa Miniature Oil Pump

Product Overview

The CBK-F8 is a classic model from the CBK-F series of high-pressure, small-displacement gear pumps, specifically engineered for various small hydraulic power units and medium-to-small hydraulic systems. The pump consists of a pair of high-strength gears, bearing bushings, housing, front cover, and rear cover. The axial clearance is automatically compensated by high-precision floating bushings, ensuring excellent mechanical and volumetric efficiency.

The F-grade pressure rating delivers a rated pressure of 20 MPa and a peak pressure of 28 MPa, with a nominal displacement of 8.08 ml/r. The pump features low noise operation and an excellent power-to-weight ratio, addressing the pressure limitations found in previous CBN series pumps.

The series supports both clockwise and counter-clockwise rotation directions, as well as five inlet/outlet port configurations (rear in/front out, side in/rear out, rear in/side out, side in/side out, rear in/rear out), providing flexible adaptability to various hydraulic system piping layouts.

As a domestic standard model, the CBK-F8 offers direct interchangeability with equivalent CBK-F8 gear pumps from other manufacturers, with fully compatible mounting dimensions — making it the ideal choice for small hydraulic system maintenance, replacement, and OEM integration.

Technical Specifications 

• Model: CBK-F8

• Series: CBK-F Series High-Pressure Gear Pump

• Nominal Displacement: 8.08 ml/r (0.493 in³/r)

• Rated Pressure (P1) : 10 MPa

• Second Stage Pressure (P2) : 14 MPa

• Maximum Pressure (P3) : 18 MPa

• Rated Speed: 2000 RPM

• Maximum Speed: 3000 RPM

• Volumetric Efficiency: ≥90%

• Overall Length (L) : 113.5 mm

• Rotation Direction: Clockwise / Counter-clockwise (optional)

• Body Material: High-strength aluminum alloy (extruded profile)

• Bearing Type: High-precision floating bushings (automatic axial clearance compensation)

• Seal Material: NBR (standard)

• Mounting Type: Flange mounting

• Port Configurations: 5 options available (rear in/front out, side in/rear out, rear in/side out, side in/side out, rear in/rear out)

• Compatible Fluids: Mineral hydraulic oil and anti-wear hydraulic fluids

• Recommended Oil: ISO VG 46 anti-wear hydraulic oil

• Operating Oil Temperature Range: 10°C – 60°C

Key Technical Advantages

1. High-Pressure, Small-Displacement Design — Efficient Power in a Compact Package

The F-grade pressure rating delivers 20 MPa rated and 28 MPa peak pressure capability at a small displacement of 8.08 ml/r. This design overcomes the pressure limitations of previous CBN series pumps, making it ideal for applications with limited installation space that still require high system pressure.

2. Automatic Axial Clearance Compensation — Sustained High Efficiency

High-precision floating bushings automatically adjust axial clearance in response to operating pressure. This technology ensures consistently high mechanical and volumetric efficiency (≥90%) throughout the pump’s service life, significantly outperforming fixed-clearance designs.

3. Compact & Lightweight Design — Excellent Power-to-Weight Ratio

High-strength aluminum alloy extruded housing delivers structural integrity while achieving lightweight construction. The pump features low noise and an excellent power-to-weight ratio, making it particularly suitable for space-constrained and weight-sensitive applications.

4. Five Flexible Port Configurations — Adaptable to Any System Layout

Support for five inlet/outlet configurations: rear in/front out, side in/rear out, rear in/side out, side in/side out, and rear in/rear out. This high level of flexibility enables OEM customers to select the optimal configuration for their specific hydraulic system piping layout without requiring additional adapter blocks.

5. Low-Noise Operation — Ideal for Indoor & Noise-Sensitive Environments

Precision gear manufacturing and optimized flow path design result in extremely low operating noise, contributing to quieter hydraulic system working environments. This characteristic makes the pump particularly suitable for indoor equipment, laboratory settings, and medical facilities where noise is a concern.

Application Areas

• Small Hydraulic Power Units — AC/DC hydraulic power stations

• Lift Platforms — Scissor lifts, vehicle-mounted lifting equipment

• Vehicle Lifts — Automotive hoists, service platforms

• Small Construction Equipment — Compact loaders, excavator auxiliary systems

• Agricultural Machinery — Small tractors, implement hydraulic systems

• Industrial Equipment — Machine tool hydraulics, light industrial machinery

• Material Handling Equipment — Manual hydraulic pallet trucks, lift carts

• Medical Equipment — Operating tables, hospital bed hydraulic adjustment systems

Expert Maintenance Tips

1. Selection & Ordering

• Confirm rotation direction (clockwise or counter-clockwise) when ordering

• Confirm inlet/outlet port configuration (5 options available) based on system piping layout

• Verify mounting flange and port specifications match the system requirements

2. Installation Requirements

• Shaft concentricity with the drive unit must be controlled within 0.1 mm

• Flexible coupling is recommended to avoid additional loads from rigid connections

• Flange bolts must be evenly tightened in a diagonal pattern to prevent housing distortion or seal failure

3. Piping & Filtration

• Inlet pipe diameter must not be smaller than the pump inlet port; piping should be as short as possible with minimal bends

• A filter must be installed on the inlet line with filtration rating ≥25 μm

• Thoroughly flush all piping with high-pressure oil before installation to prevent hard particle contamination

4. Pre-Start Checks

• Prime the pump by filling the housing with hydraulic oil before initial start-up

• Jog the motor to verify rotation direction matches pump marking; reverse rotation is strictly prohibited

• Recommended fluid: ISO VG 46 anti-wear hydraulic oil; use ISO VG 32 when ambient temperature is below 0°C

5. Operation & Maintenance

• Normal operating oil temperature should be maintained between 10°C and 60°C

• Replace hydraulic oil and filter after the first 500 hours of operation, then every 2,000 hours thereafter

• Periodically inspect pump housing connections for leaks; if abnormal noise or pressure instability occurs, shut down immediately for inspection