GPA Series Internal Gear Pump | GPA1 GPA2 GPA3 | High Pressure Low Noise

The GPA Series internal gear pumps by Chengyuan Hydraulic are high-precision power units designed for high-performance industrial hydraulic systems. Covering sizes GPA1, GPA2, and GPA3 (including specific models like GPA1-4, GPA2-10, and GPA2-16), these pumps are fully compatible with global standards. Utilizing radial and axial pressure compensation, the GPA series maintains exceptional volumetric efficiency even at 25 MPa. Its core advantage lies in extremely smooth flow output and ultra-low noise levels (typically below 65dB), making it the ideal choice for hydraulic equipment requiring high precision and a quiet working environment. As a premium replacement, every pump undergoes 100% simulated condition testing to ensure performance matches original specifications.

Technical Specifications :

• Model Range: GPA1-1.2, GPA1-4, GPA2-10, GPA2-16, GPA3-25, GPA3-63

• Displacement Range: $1.2\text{ to } 63\text{ cm}^3\text{/rev}$

• Rated Pressure: $25\text{ MPa (250 bar / 3625 psi)}$

• Peak Pressure: $31.5\text{ MPa (315 bar)}$

• Speed Range: $500\text{–}3000\text{ rpm}$

• Volumetric Efficiency: $\ge 95\%$

• Noise Level: $55\text{–}68\text{ dB(A)}$

• Shaft Options: Straight, Splined, or Tapered (e.g., EK1/2 configurations)

• Mounting Standard: Standard SAE 2-bolt flange

Key Technical Advantages:

• Dual-Direction Pressure Compensation: Advanced radial and axial compensation structures automatically adjust clearances between side plates and gear faces. This minimizes internal leakage during oil viscosity fluctuations or continuous high-pressure operation, ensuring stable output.

• Straight Conjugate Tooth Profile: The gears feature high-precision straight conjugate curves, ensuring exceptionally smooth engagement. This geometry eliminates trapped oil pockets and significantly reduces pressure ripple, leading to quieter and more stable system operation.

• High-Strength Nodular Cast Iron Housing: The pump body is manufactured from specialized high-hardness nodular cast iron, providing excellent mechanical strength and fatigue resistance. Under 25MPa cycling loads, housing deformation is negligible, maintaining internal alignment.

• Heavy-Duty Plain Bearing System: Equipped with high-load sliding bearings treated with specialized anti-wear coatings. These bearings offer a larger load-bearing surface than rolling elements, effectively absorbing shocks and extending the overall service life of the pump.

Application Areas:

• Precision Machine Tools: Primary power source for grinders, press brakes, and shearing machines.

• Plastic Machinery: Servo-hydraulic systems for injection molding and blow molding machines.

• Material Handling: Smooth lifting mechanisms for forklifts and scissor lifts.

Expert Maintenance Tips:

• Initial Priming: Never run the pump dry. Before startup, fill the pump with clean hydraulic oil and rotate the shaft manually to ensure all internal components are lubricated.

• Inlet Vacuum: Ensure the suction line is perfectly sealed. The suction height should not exceed $0.5\text{m}$ to prevent cavitation and noise caused by air intake.

• Fluid Cleanliness: Internal gear pumps are sensitive to contaminants. Maintain a fluid cleanliness of NAS Class 9 or better, and use return filters with a rating of $20\mu\text{m}$ or finer.