GPA1-1-E-20R6.3 GPA1-2-E-20R6.3 GPA1-4-E-20R6.3 Parker Gear Pump 260 bar

Product Overview

The GPA1-1-E-20R6.3, GPA1-2-E-20R6.3, GPA1-4-E-20R6.3, GPA2-6-E-20R6.3, and GPA2-10-E-20R6.3 are high-performance aluminum-body internal gear pumps from Parker Hannifin’s renowned GPA Series Low-Noise Internal Gear Pump platform. The GPA Series is manufactured using advanced design and manufacturing technology originally developed by Vickers (USA), and is widely recognized for its low noise, long service life, high reliability, and low contamination sensitivity.

This series features internal gear pump construction, available in both single pump and tandem pump configurations. Single pump displacement covers 1.76 – 63.6 mL/r across nine size options, which can be combined to form multiple tandem pump configurations. Rated pressure is available in 6.3 MPa and 10 MPa options.

Key Interchangeability Advantage: Our GPA series gear pumps are manufactured to strict Parker/Vickers original design specifications, ensuring 100% direct interchangeability with original units. All mounting interfaces, flange dimensions, shaft configurations, and port positions are identical to the original product—no modifications required. Every pump undergoes 100% factory performance testing under simulated operating conditions (covering rated pressure, peak pressure, and full speed range performance curves), guaranteeing plug-and-play reliability with zero performance deviation.

Model Code Breakdown:

• Series: GPA = Low-Noise Internal Gear Pump

• Size Code: 1 = GPA1 Series (1–7.5 cm³/rev) / 2 = GPA2 Series (4.5–31.7 cm³/rev)

• Displacement Code: 1 / 2 / 4 / 6 / 10 = Corresponding displacement size

• Mounting Type: E = European standard mounting

• Port/Flange: 20 = Specific port and flange configuration

• Rotation: R = Clockwise (viewed from shaft end)

• Rated Pressure: 6.3 = 6.3 MPa

Technical Specifications 

GPA1 Series (Group 1)

• Product Series: GPA1 Series Aluminum Internal Gear Pump

• Displacement Range: 1.0 – 7.5 cm³/rev

• GPA1-1 Displacement: Approx. 1.76 – 2.6 cm³/rev (configuration-dependent)

• GPA1-2 Displacement: Approx. 4.1 – 4.2 cm³/rev

• GPA1-4 Displacement: Approx. 6.8 cm³/rev

• Rated Continuous Operating Pressure: 6.3 MPa (standard) / 10 MPa (optional)

• Series Maximum Continuous Pressure: Up to 260 bar

• Maximum Speed: 600 – 4000 rpm

• Gear Type: Internal gear with axial clearance compensation

• Body Material: Aluminum alloy

• Direction of Rotation: R = Clockwise (standard) / L = Counter-clockwise

• Mounting: 4-bolt flange – European flange / SAE flange

• Hydraulic Connections: BSPP threaded (European flange)

• Mass: 1.3 – 1.9 kg

• Operating Temperature Range: -20°C to +80°C

• Recommended Fluid Viscosity: 10 – 750 cSt

GPA2 Series (Group 2)

• Product Series: GPA2 Series Aluminum Internal Gear Pump

• Displacement Range: 4.5 – 31.7 cm³/rev

• GPA2-6 Displacement: Approx. 10.3 cm³/rev

• GPA2-10 Displacement: Approx. 16.6 cm³/rev

• Rated Continuous Operating Pressure: 6.3 MPa (standard) / 10 MPa (optional)

• Series Maximum Continuous Pressure: Up to 260 bar

• Maximum Speed: 600 – 4000 rpm

• Gear Type: Internal gear with axial clearance compensation

• Body Material: Aluminum alloy

• Direction of Rotation: R = Clockwise (standard) / L = Counter-clockwise

• Mounting: 4-bolt flange – European flange / SAE flange

• Hydraulic Connections: BSPP threaded (European flange)

• Mass: 3.3 – 4.6 kg

• Operating Temperature Range: -20°C to +80°C

• Recommended Fluid Viscosity: 10 – 750 cSt

Key Technical Advantages

1. Aluminum Body with Axial Clearance Compensation for High Efficiency

The GPA Series features a high-strength aluminum housing with axial clearance compensation, ensuring automatic hydraulic clearance adjustment between gears and housing under all operating conditions. This design significantly improves volumetric efficiency, delivering stable flow output even under high-pressure conditions.

2. Internal Gear Construction for Ultra-Low Noise Operation

The GPA Series employs internal gear design, which delivers significantly lower pressure pulsation and noise levels compared to conventional external gear pumps. The low-noise characteristic substantially improves operator working conditions and is particularly suitable for noise-sensitive precision machine tools and indoor equipment.

3. High Reliability and Long Service Life

Optimized bearing load balancing system effectively reduces wear on critical components. The product features simple construction, smooth operation, high reliability, and convenient maintenance. Low contamination sensitivity provides relative tolerance to hydraulic system filtration requirements.

4. Flexible Configurations and Tandem Pump Combination Capability

The GPA Series offers nine displacement options with single pump displacement covering 1.76 – 63.6 mL/r. Different displacements can be freely combined to form multiple tandem pump configurations. Supports both European flange and SAE flange mounting standards.

5. Wide Operating Range

Rated pressure available in 6.3 MPa and 10 MPa options, with speed range covering 600 – 4000 rpm. The broad operating range ensures optimal matching under all operating conditions.

Application Areas

• Precision Machine Tools: Grinding machines, lathes, milling machines, machining center hydraulic systems

• General Machinery: Hydraulic transmission and control systems for various general-purpose machine tools

• Injection Molding Machinery: Injection molding machines, rubber vulcanizing press hydraulic systems

• Construction & Engineering Machinery: Mining machinery, die-casting machines, pipe benders

• Material Handling Equipment: Electric forklifts, lifting equipment

• Packaging Machinery: Food packaging machinery hydraulic drives

• Petrochemical Machinery: Hydraulic systems in petrochemical applications

• Wood Processing and Food Processing Machinery

Expert Maintenance Tips

1. Pre-Installation Checks

• GPA Series pumps are rotation-sensitive—verify pump rotation direction (R=Clockwise / L=Counter-clockwise) matches system requirements before installation. Reverse rotation will prevent proper pump operation.

• Check mounting flange type (European 4-bolt flange or SAE flange) to ensure compatibility with system interface.

• Confirm port connections are BSPP threaded and precisely match hydraulic fittings.

2. First Start-Up & Oil Priming

• Prime the pump housing with clean hydraulic oil before first start-up; ensure the suction line is fully filled—never run dry.

• Recommended hydraulic fluid: anti-wear hydraulic oil per DIN 51524, viscosity range 10 – 750 cSt.

• Maintain operating oil temperature within -20°C to +80°C.

3. Filtration & Fluid Cleanliness

• Although the GPA Series has low contamination sensitivity—if abnormal noise or pressure fluctuation occurs, first check for air ingestion in the system.

• Regularly check torque on pump and piping connection bolts to prevent loosening from vibration.

• Internal gear pumps are sensitive to fluid viscosity changes—regularly monitor fluid viscosity.

5. Tandem Pump Special Considerations

• For tandem pump configurations, ensure each pump stage suction port maintains adequate inlet pressure.

• Total drive torque of tandem pumps is the sum of all pump stage torques—ensure prime mover output torque meets system requirements.