1. Product Overview
Model: KFG80 / KFG63
Type: External Gear Hydraulic Pump
Manufacturer: Kawasaki Heavy Industries (or authorized suppliers)
Key Features:
• Compact Design: Lightweight and space-saving for constrained hydraulic systems.
• High Efficiency: Precision gear meshing achieves volumetric efficiency up to 85%-90%.
• Low Maintenance Cost: Simple structure with easy disassembly and universal spare parts.
• Versatile Adaptability: Compatible with mineral oils, synthetic hydraulic fluids, and resistant to contamination.
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2. Technical Specifications
【表格】
Parameter KFG80 KFG63 Notes
Displacement 80 mL/rev (per revolution) 63 mL/rev Theoretical flow = Displacement × Speed
Rated Pressure 21 MPa (continuous operation) 21 MPa Peak pressure up to 28 MPa (short-term)
Speed Range 600–3000 rpm 600–3000 rpm Optimal efficiency at 1800–2500 rpm
Volumetric Efficiency ≥88% (at 21 MPa) ≥88% Slight decline with pressure increase
Weight ~12 kg ~10 kg Includes shaft seal and standard flange
Port Sizes Inlet/Outlet: G1¼" (BSP) G1" (BSP) Customizable to NPT or SAE threads
Applicable Media Mineral-based hydraulic oil (VG32-68) Synthetic hydraulic oil (phosphate esters) Viscosity range: 10–400 cSt (40℃)
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3. Structure & Working Principle
• Components:
• Drive Gear: Connected to the input shaft, rotates the driven gear.
• Driven Gear: Meshes with the drive gear to form a sealed volume.
• Pump Body: Cast iron or aluminum alloy housing with gear chambers and oil passages.
• Shaft Seal: Double-lip or mechanical seal to prevent leakage.
• Side Plate: Adjusts gear end clearance to compensate for wear.
• Operation:
1. Suction Phase: Gears disengage, creating a vacuum to draw in hydraulic fluid.
2. Discharge Phase: Gears mesh, compressing fluid to the outlet under pressure.
3. Continuous Flow: Rotation of the input shaft ensures uninterrupted oil supply.
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4. Typical Applications
• Construction Machinery:
• Lubrication systems for excavators and loaders (e.g., slew bearing lubrication).
• Auxiliary hydraulic circuits for crane boom adjustment and outrigger extension.
• Industrial Equipment:
• Hydraulic clamping systems in injection molding and die-casting machines.
• Tool feed and coolant pump drives in machine tools.
• Agricultural Machinery:
• Hydraulic power take-off (PTO) units in tractors.
• Header lift control in combine harvesters.
• Special Environments:
• Hydraulic starting systems for mobile generators.
• Low-pressure oil supply for fire truck ladder extension.
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5. Selection & Matching Guide
• Flow Calculation:
• Required flow = System demand ÷ Pump efficiency (typically 0.85–0.9).
• Example: For a system requiring 40 L/min, select displacement ≥ (40÷0.9)÷motor speed (e.g., 1500 rpm) ≈ 29.6 mL/rev → KFG63 may require speed adjustment or parallel pumps.
• Pressure Matching:
• Ensure maximum system pressure ≤ 80% of pump rated pressure (i.e., ≤16.8 MPa for long-term operation).
• Motor Power:
• Drive power (kW) = Flow (L/min) × Pressure (MPa) ÷ 60 ÷ Efficiency
• Example: KFG80 at 21 MPa and 1500 rpm requires ≈ 80×21÷60÷0.85 ≈ 33.3 kW.
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6. Installation & Maintenance
• Installation Requirements:
• Align pump and motor shafts within 0.05 mm tolerance.
• Maintain suction port height ≤500 mm (avoid cavitation) and equip with a filter (≤100 μm).
• Install a relief valve (set pressure ≤25 MPa) in the outlet line.
• Routine Maintenance:
• Oil Inspection: Check cleanliness every 500 hours (NAS 6 or cleaner) and replace periodically.
• Leakage Check: Replace seals if leakage exceeds 5 drops/minute.
• Noise Monitoring: Investigate abnormal vibrations or noise (>85 dB) for gear wear.
• Critical Spare Parts:
• Shaft seal (Part No.: KFG-SEAL-80/63)
• Gear set (replace in pairs, Part No.: KFG-GEAR-SET)
• Side plate (Part No.: KFG-SIDE-PLATE)
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7. Troubleshooting
【表格】
Symptom Possible Causes Solutions
Insufficient flow Clogged suction filter, worn gears Clean filter or replace gear set
Pressure fluctuations Air ingress, excessive side clearance Check seals, adjust side plate preload
Overheating High oil viscosity, overspeed Use correct viscosity oil, reduce speed
Abnormal noise Bearing failure, gear pitting Replace bearings or gear set
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8. Precautions
1. Avoid Dry Running: Prime the pump with oil before startup to prevent gear wear.
2. Media Compatibility: Do not use water-based fluids or corrosive additives.
3. Cold Start: Preheat oil to ≥20℃ if ambient temperature < -10℃.
4. Long-Term Storage: Clean the pump, apply rust inhibitor, and rotate the shaft to prevent seizure.
