P30 P31 Parker Gear Pump Dump Truck 207bar 16-64cc

Product Overview

The P30/P31、P50/P51、P75/P76 series cast iron gear pumps are core products of the Parker Hannifin Commercial product line, specifically engineered for dump truck hoist systems and other heavy-duty applications. This series is the former Commercial Intertech product line, holding over 70% market share in the North American dump truck market.

P30/P31 series displacements range from 16.1 – 64.6 cm³/rev; P50/P51 series from 20.9 – 104.5 cm³/rev; P75/P76 series from 33 – 199 cm³/rev. All series are rated at 172 – 207 bar (2,500 – 3,000 psi) .

Engineered with high-strength cast iron housing and pressure-balanced thrust plates, the pumps deliver high volumetric efficiency (≥95%), excellent contamination resistance, and extended service life. Widely used in dump trucks, tipper trucks, and roll-off trucks hydraulic hoist systems.

Every unit is manufactured to original equipment specifications, ensuring 100% drop-in interchangeability with genuine Parker Commercial P series pumps without any system modifications. Each pump undergoes rigorous 100% simulated duty-cycle testing to validate pressure-flow-efficiency performance curves.

Brand Disclaimer: This product is a high-quality compatible replacement engineered for full interchangeability with Parker Hannifin Commercial original equipment. All Parker brand names and model codes are referenced solely to indicate compatibility and interchangeability. This product is manufactured by an independent producer and is not an original Parker product.

Technical Specifications 

P30/P31 Series

• Product Series: Parker Commercial P30/P31

• Product Type: Fixed Displacement External Gear Pump

• Displacement Range: 16.1 – 64.6 cm³/rev (0.985 – 3.94 in³/rev)

• Rated Pressure: 207 bar (3,000 psi) 

• Maximum Pressure (Intermittent) : 248 bar (3,600 psi) 

• Maximum Speed: 2,400 rpm

• Maximum Flow Rate: 38.4 GPM (145.4 L/min) 

• Housing Material: High-strength cast iron

• Bearings: Roller bearings / Bushing bearings

• Thrust Plates: Pressure Balanced Thrust Plates

• Mounting: SAE standard flange mounting

• Rotation: Clockwise / Counterclockwise available

• Hydraulic Fluid: Mineral oil

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

• Multi-Pump: Single, tandem, triple combinations available

P50/P51 Series

• Product Series: Parker Commercial P50/P51

• Product Type: Fixed Displacement External Gear Pump

• Displacement Range: 20.9 – 104.5 cm³/rev (1.28 – 6.38 in³/rev)

• Rated Pressure: 207 bar (3,000 psi) 

• Maximum Pressure (Intermittent) : 248 bar (3,600 psi) 

• Maximum Speed: 2,400 rpm

• Maximum Flow Rate: 66 GPM (250 L/min) 

• Housing Material: High-strength cast iron

• Bearings: Roller bearings / Bushing bearings

• Thrust Plates: Pressure Balanced Thrust Plates

• Mounting: SAE standard flange mounting

• Rotation: Clockwise / Counterclockwise available

• Hydraulic Fluid: Mineral oil

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

• Multi-Pump: Single, tandem, triple combinations available

P75/P76 Series

• Product Series: Parker Commercial P75/P76

• Product Type: Fixed Displacement External Gear Pump

• Displacement Range: 33 – 199 cm³/rev (2.0 – 12.14 in³/rev)

• Rated Pressure: 207 bar (3,000 psi) 

• Maximum Pressure: 250 bar (selected models)

• Maximum Speed: 2,000 rpm

• Minimum Speed: 400 rpm

• Maximum Flow Rate: 128 GPM (484 L/min) 

• Housing Material: High-strength cast iron

• Bearings: Roller bearings

• Thrust Plates: Pressure Balanced Thrust Plates

• Volumetric Efficiency: ≥95%

• Mounting: SAE standard flange mounting

• Rotation: Clockwise / Counterclockwise available

• Hydraulic Fluid: Mineral oil

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

• Multi-Pump: Single, tandem, triple, and multiple combinations available

Key Technical Advantages

1. High-Strength Cast Iron Construction – Extreme Durability

The high-strength cast iron housing delivers superior structural rigidity and pressure containment compared to aluminum alternatives. Particularly suited for dump truck hoist systems operating under high vibration, high shock, and high contamination conditions.

2. Pressure-Balanced Thrust Plates – High Volumetric Efficiency

Integrated pressure-balanced thrust plates automatically compensate for gear end clearance under high pressure, significantly reducing internal leakage. Volumetric efficiency reaches 95% or higher, maintaining stable flow output across the full pressure range.

3. Excellent Contamination Resistance

The cast iron housing with precision-machined internal components delivers excellent contamination resistance. Effectively withstands fluid contamination in harsh off-highway equipment environments such as dump trucks, extending service life.

4. Modular Design – Flexible Multi-Section Expansion

P30/P31, P50/P51, and P75/P76 series support single, tandem, triple, and multiple pump configurations. Flexible combinations adapt to different tonnage dump truck hoist system flow requirements.

5. Extensive Integrated Valve Options

Supports integration of multiple control valve functions including: Priority Valves, Two-speed Valves, and Unloading Valves. Significantly reduces external valve groups and piping, improving system integration and reliability.

6. North American Standard Interface – 100% Drop-In Interchangeability

Strictly complies with SAE standard flanges, shafts, and port configurations. Delivers 100% drop-in interchangeability with Parker Commercial, Muncie, Permco, Metaris, and other brand equivalents.

7. 100% Simulated Duty-Cycle Testing

Every pump is 100% tested on dedicated hydraulic test benches under simulated real-world operating conditions—validating pressure-flow characteristics and efficiency curves at rated pressure and full speed range—ensuring zero-defect, plug-and-play performance upon installation.

Application Areas

• Dump Trucks: Body hoist and lower hydraulic systems

• Tipper Trucks: Hydraulic hoist systems

• Roll-off Trucks: Container loading/unloading hydraulic systems

• Trailers: Hydraulic suspension and hoist systems

• Construction Equipment: Loader, excavator auxiliary hydraulic systems

• Material Handling Equipment: Forklifts, stacker hydraulic systems

Expert Maintenance Tips

1. Fluid Cleanliness Control

Maintain system fluid cleanliness to ISO 4406 19/17/14 or better. Install a 10–25 μm absolute filtration filter upstream of the inlet port to prevent particle contamination from damaging precision gear pairs and thrust plates.

2. Inlet Line Requirements

Keep suction lines short and straight with adequate diameter—not less than the port size. Recommended suction line flow velocity: ≤1.5 m/s to prevent cavitation from excessive inlet resistance. Inlet pressure must be maintained between 0.8–2.0 bar (absolute) .

3. Coupling Alignment Precision

Ensure pump shaft-to-drive shaft coaxiality deviation ≤0.05 mm and angular deviation ≤0.5° during installation. Flexible couplings are strongly recommended. For PTO-driven applications, ensure driveline alignment meets specifications.

4. First-Start Priming Procedure

Before initial startup, prime the pump by bleeding air through the drain port or a loosened outlet fitting. Perform 2–3 jog starts with the outlet open (no load) until oil fills the pump cavity without air bubbles, then connect the load circuit for full operation.

5. Hoist System Pressure Setting

The dump truck hoist system relief valve pressure should be set within the pump’s rated pressure range (207 bar). Never exceed rated pressure to avoid pump and system damage.

6. Viscosity & Temperature Monitoring

Recommended operating viscosity: 12–100 cSt. Operating temperature range: -20°C to +80°C. During cold starts when viscosity exceeds the recommended range, ensure adequate suction conditions or preheat the fluid.