Parker PD Series Axial Piston Pump | PD045 PD028 | Variable Displacement Pump

The PD Series axial variable displacement piston pumps by Chengyuan Hydraulic are high-pressure units engineered to be fully compatible with Parker industrial standards. Covering mainstream displacements such as PD045 (45cc) and PD028 (28cc), including specific codes like PD045PS02SRS5AC10R…, these pumps are tailored for industrial environments requiring compact footprints and minimal pressure ripple. We utilize high-strength ductile iron housings and precision-lapped valve plates to ensure exceptional volumetric efficiency at continuous pressures of 28 MPa. As a premier replacement solution, every unit undergoes 100% simulated condition testing to ensure that control responsiveness—especially for pressure compensation—matches original factory performance.

Technical Specifications :

• Model Range: PD018, PD028, PD045, PD060, PD075, PD100, PD140

• Displacement: $18\text{ to } 140\text{ cm}^3\text{/rev}$ (PD045 = $45\text{ cc}$)

• Rated Pressure: $28\text{ MPa (280 bar / 4000 psi)}$

• Peak Pressure: $31\text{ MPa (310 bar / 4500 psi)}$

• Max Speed: Up to $3000\text{ rpm}$ (Approx. $2600\text{ rpm}$ self-priming for PD045)

• Control Types: PS (Pressure Compensator), RS (Remote Control), LS (Load Sensing), etc.

• Shaft Ends: SAE Splined or Straight Keyed (e.g., Code SRS5)

• Mounting Flange: SAE Standard (e.g., SAE B 2-bolt)

• Weight: Approx. $22\text{–}25\text{ kg}$ (PD045 size)

Key Technical Advantages:

• Compact High-Power Design: The PD series utilizes an optimized swashplate geometry, resulting in an axial length approximately $15\%$ shorter than traditional piston pumps. This compact design is ideal for tight industrial manifold layouts and improves the power-to-weight ratio.

• Low Noise & Extended Bearing Life: Equipped with large tapered roller bearings designed to withstand high radial and axial loads. Combined with an optimized valve plate featuring noise-reduction silencing grooves, the fluid noise during high-pressure switching is significantly dampened.

• Responsive Control Compensators: The control valve blocks are precision-calibrated. Whether using PS or LS controls, the on/off-stroke response times are measured in milliseconds, minimizing energy loss through bypass flow and reducing system heat generation.

• Superior High-Speed Self-Priming: Inlet flow paths are optimized via CFD simulation, maintaining stable charging efficiency even with lower inlet pressures or higher viscosity fluids. This drastically reduces the risk of cavitation during high-speed operation.

Application Areas:

• Industrial Presses: Primary variable pump for forming machines, stamping presses, and brick-making machines.

• Machine Tool Power: Load-sensing systems for CNC machining center hydraulic stations and clamping mechanisms.

• Injection Molding: Energy-saving pressure regulation for servo or conventional injection molding machines.

Expert Maintenance Tips:

• Case Priming: Before the initial startup, the pump housing must be filled with clean hydraulic oil through the top case port. Never run the pump dry, as this will cause catastrophic galling of the swashplate and slippers within seconds.

• Case Pressure Limit: Ensure the case drain line is connected directly to the tank and ends below the oil level. Case pressure must not exceed $0.2\text{ MPa (2 bar)}$; excessive backpressure will cause early shaft seal failure and sluggish variable response.

• Filtration Standards: To ensure the precision of the variable control mechanism, system return filtration should be no less than $10\mu\text{m}$. Maintain fluid cleanliness levels at or above ISO 18/16/13.