GPY-8R SHIMADZU Hydraulic Gear Pump 8.01 cm³/rev 20.6 MPa

Product Overview

The GPY series is a highly representative external high-pressure gear pump product line from SHIMADZU, renowned for its high efficiency, light weight, and low noise. This series includes standard models GPY-3R, GPY-4R, GPY-5.8R, GPY-7R, GPY-8R, GPY-9R, GPY-10R, and GPY-11.5R, as well as derivative models with three-digit suffixes such as GPY-3R870, GPY-4R872, and GPY-7R887. These pumps are widely used in hydraulic power units, forklifts, construction machinery, and various industrial applications.

As a professional hydraulic component manufacturer, we provide 100% interchangeable replacement solutions for the SHIMADZU GPY series. Every GPY series gear pump undergoes 100% performance testing under simulated actual operating conditions—from displacement accuracy and pressure stability to volumetric efficiency—fully benchmarked against SHIMADZU original equipment standards. The pump body is manufactured from high-strength cast aluminum alloy, featuring high-strength explosion-proof anti-crack characteristics, with gear units precision-machined and hardened to ensure exceptional durability and reliability.

Model Code Explanation:

• GPY: SHIMADZU gear pump series code

• Number (3/4/5.8/7/8/9/10/11.5): Theoretical output flow in cm³/rev

• R: Rotation direction — R = Clockwise (viewed from shaft end); L = Counter-clockwise

• Three-digit suffix (e.g., 870, 872, 887, 877): Derivative model codes representing different mounting flange types, shaft configurations, or seal specifications

Technical Specifications 

GPY-3R

• Theoretical Displacement: 2.98 cm³/rev

• Rated Pressure: 20.6 MPa (210 kgf/cm²)

• Peak Pressure: 22.6 MPa (230 kgf/cm²)

• Minimum Speed: 700 min⁻¹

• Maximum Speed: 3,000 min⁻¹

• Control Type: External gear pump, fixed displacement

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

• Mounting Type: Flange mounting (JIS 4-bolt)

• Fluid Compatibility: Petroleum-based hydraulic fluid

• Weight: Approx. 1.2 kg

GPY-4R

• Theoretical Displacement: 4.09 cm³/rev

• Rated Pressure: 20.6 MPa (210 kgf/cm²)

• Peak Pressure: 22.6 MPa (230 kgf/cm²)

• Minimum Speed: 500 min⁻¹

• Maximum Speed: 3,000 min⁻¹

• Control Type: External gear pump, fixed displacement

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

• Mounting Type: Flange mounting (JIS 4-bolt)

• Fluid Compatibility: Petroleum-based hydraulic fluid

• Weight: Approx. 1.2 kg

GPY-5.8R

• Theoretical Displacement: 5.77 cm³/rev

• Rated Pressure: 20.6 MPa (210 kgf/cm²)

• Peak Pressure: 22.6 MPa (230 kgf/cm²)

• Minimum Speed: 500 min⁻¹

• Maximum Speed: 3,000 min⁻¹

• Control Type: External gear pump, fixed displacement

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

• Mounting Type: Flange mounting (JIS 4-bolt)

• Fluid Compatibility: Petroleum-based hydraulic fluid

• Weight: Approx. 1.2 kg

GPY-7R / GPY-7R887

• Theoretical Displacement: 7.07 cm³/rev

• Rated Pressure: 20.6 MPa (210 kgf/cm²)

• Peak Pressure: 22.6 MPa (230 kgf/cm²)

• Minimum Speed: 500 min⁻¹

• Maximum Speed: 3,000 min⁻¹

• Control Type: External gear pump, fixed displacement

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

• Mounting Type: Flange mounting (JIS 4-bolt)

• Fluid Compatibility: Petroleum-based hydraulic fluid

• Weight: Approx. 1.2 kg

• Note: GPY-7R887 is a derivative model with 887 suffix

GPY-8R

• Theoretical Displacement: 8.01 cm³/rev

• Rated Pressure: 20.6 MPa (210 kgf/cm²)

• Peak Pressure: 22.6 MPa (230 kgf/cm²)

• Minimum Speed: 500 min⁻¹

• Maximum Speed: 3,000 min⁻¹

• Control Type: External gear pump, fixed displacement

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

• Mounting Type: Flange mounting (JIS 4-bolt)

• Fluid Compatibility: Petroleum-based hydraulic fluid

• Weight: Approx. 1.2 kg

GPY-9R

• Theoretical Displacement: 8.94 cm³/rev

• Rated Pressure: 20.6 MPa (210 kgf/cm²)

• Peak Pressure: 22.6 MPa (230 kgf/cm²)

• Minimum Speed: 500 min⁻¹

• Maximum Speed: 3,000 min⁻¹

• Control Type: External gear pump, fixed displacement

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

• Mounting Type: Flange mounting (JIS 4-bolt)

• Fluid Compatibility: Petroleum-based hydraulic fluid

• Weight: Approx. 1.4 kg

GPY-10R

• Theoretical Displacement: 10.06 cm³/rev

• Rated Pressure: 20.6 MPa (210 kgf/cm²)

• Peak Pressure: 22.6 MPa (230 kgf/cm²)

• Minimum Speed: 500 min⁻¹

• Maximum Speed: 3,000 min⁻¹

• Control Type: External gear pump, fixed displacement

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

• Mounting Type: Flange mounting (JIS 4-bolt)

• Fluid Compatibility: Petroleum-based hydraulic fluid

• Weight: Approx. 1.4 kg

GPY-11.5R

• Theoretical Displacement: 11.55 cm³/rev

• Rated Pressure: 20.6 MPa (210 kgf/cm²)

• Peak Pressure: 22.6 MPa (230 kgf/cm²)

• Minimum Speed: 500 min⁻¹

• Maximum Speed: 2,500 min⁻¹

• Control Type: External gear pump, fixed displacement

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

• Mounting Type: Flange mounting (JIS 4-bolt)

• Fluid Compatibility: Petroleum-based hydraulic fluid

• Weight: Approx. 1.4 kg

GPY-3R870 / GPY-4R872 (Derivative Models)

• Series: GPY-3 / GPY-4 series derivative configurations

• Rated Pressure: Approx. 20.6 MPa

• Maximum Speed: Approx. 2,800 min⁻¹

• Control Type: External gear pump, fixed displacement

• Rotation Direction: R (Clockwise)

• Mounting Type: Flange mounting

• Fluid Compatibility: Petroleum-based hydraulic fluid

Important Note: The above specifications are compiled from SHIMADZU official technical documentation. Three-digit suffixes (870/872/887/877, etc.) represent different mounting flange types, shaft configurations, or seal specifications. Please refer to the product nameplate or technical agreement for exact specifications.

Key Technical Advantages

1. High-Strength Cast Aluminum Alloy Body — Lightweight with High Strength

The GPY series pump body is manufactured from high-strength cast aluminum alloy, offering both high-strength explosion-proof anti-crack characteristics and significant weight reduction. Compared to traditional cast iron pump bodies, cast aluminum alloy dramatically reduces pump weight while maintaining excellent rigidity and impact resistance. The body features high-precision molding to ensure dimensional accuracy and performance stability.

2. Precision Structure Design — High Volumetric and Mechanical Efficiency

The GPY series features a precise and detailed structural design, delivering both high volumetric efficiency and high mechanical efficiency. Precise gear meshing clearance control and optimized oil passage design minimize internal leakage and pressure loss, ensuring every drop of flow is effectively utilized.

3. High-Strength Fastening Bolts with Superior Sealing — High-Pressure Resistant and Leak-Proof

The pump body is secured with multiple high-strength fastening bolts, providing excellent sealing performance, leak resistance, and high-pressure tolerance. Even under the demanding conditions of 20.6 MPa rated pressure and 22.6 MPa peak pressure, sealing integrity remains outstanding.

4. High-Performance Bearings with Wear-Resistant Design — Extended Service Life

The GPY series utilizes high-performance, high-wear-resistance bearings that operate stably under high-pressure, high-speed conditions without burning out. Gears and bearings undergo special hardening treatments, significantly extending pump service life. The GPY series is supported by dedicated service kits and seals for easy maintenance.

5. Compact Structure — Minimal Installation Space Requirements

The GPY series features a compact structural design with small overall dimensions and light weight (maximum only 1.4 kg). This characteristic makes it particularly suitable for applications with limited installation space, reducing the complexity of system integration.

Application Areas

• Forklift Hydraulic Systems: Power supply for fork lifting, tilting, and other hydraulic actions

• Hydraulic Power Units: Power elements for various industrial hydraulic stations

• Construction Machinery: Hydraulic systems for mini excavators, loaders, and related equipment

• Agricultural Machinery: Hydraulic suspension systems for tractors

• Machine Tool Hydraulic Systems: Hydraulic clamping and feed systems

• Marine Equipment: Auxiliary hydraulic systems for small vessels

• Injection Molding Machines: Hydraulic systems for molding equipment

• Petroleum, Chemical, Power, Metallurgy: General industrial hydraulic and lubrication systems

Expert Maintenance Tips

1. Verify Rotation Direction

GPY series pumps must only be operated in the specified rotation direction. Always verify that the rotation direction marked on the nameplate — R = Clockwise (viewed from shaft end), L = Counter-clockwise — matches the drive motor’s rotation. Reverse operation will prevent proper suction and damage the shaft seal.

2. Never Run Dry

Avoid dry running under all circumstances. Ensure the pump cavity is filled with the medium before startup; otherwise, severe wear or seizure of gears and bearings may occur.

3. Fluid Cleanliness Requirements

Gear pumps are sensitive to fluid cleanliness. Use hydraulic fluid meeting NAS Class 7 or higher cleanliness standards. Install appropriately rated filters on the pump suction side. Recommended maximum solid particle size is 30 µm.

4. Speed Range Control

Different GPY models have specific minimum and maximum speed limits. GPY-3R has a minimum speed of 700 min⁻¹, while other models have a minimum speed of 500 min⁻¹. GPY-11.5R has a maximum speed of 2,500 min⁻¹, while other models have a maximum speed of 3,000 min⁻¹. Never operate outside the specified speed range.

5. Pressure Limits

Rated pressure is 20.6 MPa, with peak pressure 22.6 MPa. Peak pressure is permitted for short-term transient conditions only — never exceed rated pressure during continuous operation to avoid damage to the pump body or seals.

6. Regular Inspection and Maintenance

Regularly inspect the system filter element condition. If abnormal noise or system pressure drop is detected, shut down immediately for inspection. The GPY series is supported by dedicated service kits and seals for convenient on-site maintenance.