HGP-2A Series Hydraulic Gear Pump HGP-2A-F12R HGP-2A-F2R HGP-2A-F25R

The industrial-grade HGP-2A Series High-Pressure External Gear Hydraulic Oil Pumps, engineered by Chengyuan Hydraulic, are fixed-displacement fluid power components developed for industrial mini hydraulic power packs, generalized lifting systems, machine tool auxiliaries, and mobile agricultural vocational equipment. Operating as an industry standard for compact fluid power generation, this series features an extruded high-strength aluminum alloy casing paired with an axial pressure-compensated floating thrust plate design. This structural layout enables the pump to maintain a stable volumetric efficiency curve at working pressures up to 250 bar while keeping mechanical noise to a minimum.

This professional B2B technical copywriting profiles and replaces the core models and displacements within this specific frame size: HGP-2A-F12R, HGP-2A-F2R (corresponding to the reference designation HGP-2A-2), and HGP-2A-F25R (corresponding to the reference designation HGP-2A-25). Decoded through global gear pump nomenclature, the model designation identifies: HGP (High-Pressure Gear Pump Platform), 2A (Standard 2A framework utilizing a 4-bolt rectangular positioning mounting flange and standard geometric layout), F12 / F2 / F25 (representing nominal displacements of 12 cc/rev, 2 cc/rev, and 25 cc/rev, respectively), and R (Clockwise rotation, with L/Counter-Clockwise variants available for custom orders). These pumps are widely integrated into car lifts, motorized tailgates, waste balers, injection molding mold-adjustment systems, and medium-to-small hydraulic stations.

Chengyuan’s alternative gear pumps perfectly realign with original technical standards regarding mounting flange configurations (pilot diameter and 4-bolt layout dimensions), input drive shafts (straight keyed, Woodruff keyed, or 9-tooth splined options), and fluid port threads (side or rear configuration options). This precision engineering delivers 100% direct drop-in interchangeability for international B2B purchasers, commercial fluid power distributors, and OEM assembly lines. Maintenance teams can replace an existing unit without modifying the bell housing, motor couplings, suction hoses, or high-pressure piping, saving assembly time and reduction of field service expenses.

Because of their compact design, external gear pumps operating under prolonged high-pressure loads expose their internal thrust plates, gear faces, and journal bearings to significant mechanical stress and fluid shear. Lower-grade alternatives often suffer from rapid volumetric efficiency drops due to scuffed thrust plates, or experience excessive heat and loud whining caused by premature bearing wear. To ensure dependable performance, 100% of Chengyuan’s HGP-2A series replacement pumps undergo 100% strict dynamic load testing on digitized simulation benches. Each pump is evaluated for flow rates, temperature rise curves, breakaway pressure thresholds, and seal integrity before delivery.

Technical Specifications

• Product Classification: Fixed Displacement External Hydraulic Gear Pump

• Standard Mounting Frame Platform: Size 2A Framework (Standard 4-Bolt square positioning flange, pilot diameter of $36.5\text{ mm}$)

• Exact Model Designation & Performance Parameters Matrix:

  • Replacement Reference: HGP-2A-F2R: Nominal geometric displacement of 2 cc/rev. Maximum continuous pressure rated up to 250 bar, with a maximum rotational speed threshold of 4000 rpm (recommended continuous at 3000 rpm).

  • Replacement Reference: HGP-2A-F12R: Nominal geometric displacement of 12 cc/rev. Maximum continuous pressure rated up to 250 bar, maximum rotational speed of 3000 rpm, delivering a nominal flow rate of approximately 17.4 L/min when paired with a standard 1450 rpm 4-pole electric motor.

  • Replacement Reference: HGP-2A-F25R: Nominal geometric displacement of 25 cc/rev. Maximum continuous pressure rated up to 210 bar, intermittent peak pressure handling up to 250 bar, with a maximum rotational speed threshold of 2500 rpm.

• Rated Maximum Continuous Pressure Spectrum: 210 bar to 250 bar (subject to specific model displacement size)

• Maximum Permissible Intermittent Peak Pressure Threshold: Up to 280 bar (4060 psi)

• Input Drive Shaft Options: Standard straight keyed shaft or Woodruff keyed configurations; optional short involute splines available

• Fluid Inlet & Outlet Connections: Standard parallel internal pipe threads or split-flange porting configured as Side Ports (Inlet/Outlet on sides) or Rear Ports (Inlet/Outlet on rear cover)

• Permissible Continuous Operating Medium Oil Temperature: -20°C to +80°C

• Target Medium Filtration Cleanliness Level: Maintained to ISO 4406 19/17/14 or higher

Key Technical Advantages

• Axial Pressure-Compensated Floating Thrust Plates: The pump features high-precision aluminum alloy thrust plates on both sides of the gear assembly, backed by special pressure-energized “3-shape” or “DU-shape” elastomer seal configurations. During operation, high-pressure fluid targets the back of the plates to press them against the gear faces, maintaining a micron-scale operating clearance. This dynamic compensation ensures a volumetric efficiency $\ge 93\%$ at 250 bar by limiting internal cross-port leakage.

• High-Tensile Extruded Aluminum Alloy Body Modules: The main pump housing is manufactured from high-grade extruded aluminum alloy with high elongation properties, while the front and rear covers are made from heavy-wall cast iron or thick-section alloy. The entire assembly is secured with high-tensile tie-bolts under precise torque specs. This rigidity minimizes housing expansion during pressure spikes to protect the tight gear-to-body clearance and prevent interior scoring.

• High-Load DU Self-Lubricating Journal Bushings: The gear shafts are supported by advanced steel-backed, bronze-sintered PTFE (DU) composite journal bearings. These bushings provide high load capacity and wear resistance against radial hydraulic forces. They utilize a micro-flow lubrication line from the pressure zone to maintain a continuous hydrodynamic oil film across the shaft journals, reducing friction and dampening mechanical noise.

• Precision-Ground Modified Involute Gear Profiles: The primary and driven gears are forged from premium chrome-molybdenum alloy steel (such as 20CrMnTi), case-hardened, and finished on CNC grinding machinery. The modified involute profiles ensure smooth tooth contact and eliminate trapped oil volume between teeth. This removes the main cause of fluid trapping, reducing fluid-borne vibration and pressure spikes for quieter operation.

Application Areas

Chengyuan’s high-performance replacement HGP-2A series gear pumps deliver reliable fixed-displacement fluid power across various space-restricted and high-pressure system loops:

• Miniature Hydraulic Power Units & Power Packs: Scissor lift tables, automotive workshop vehicle lifts, dock levelers, commercial vehicle motorized tailgates, and small dump truck lift assemblies.

• Material Handling & Light Vocational Machinery: Low-profile industrial waste balers, refuse compaction stations, electric walkie stackers, and auxiliary lift blocks for electric forklifts.

• Industrial Machine Tools & Factory Automation Lines: Auxiliary workholding clamp systems for CNC centers, fluid cooling and lubrication circulation loops, automated tool changer stations, and ejector cylinder loops on automated assembly lines.

Expert Maintenance Tips

• Prior to Initial Startup, the Pump Casing Must Be Pre-Primed with Clean, Filtered Hydraulic Oil via the Suction Port, and the Input Shaft Rotated Several Turns by Hand: The internal clearances are very tight, and the journal bearings and thrust plates rely entirely on the system fluid for immediate lubrication. Running the pump dry—especially at motor speeds of 1450 rpm or higher—can cause rapid frictional heating within seconds, scoring the thrust plates and damaging the shaft seal.

• Do Not Install Excessively Fine Filters (e.g., Smaller Than 100 Microns) Directly on the Pump’s Fluid Suction Port, and Ensure the Intake Plumbing is Completely Sealed Against Air Leaks: High flow restriction on the suction side can cause the intake pressure to drop below the fluid’s vapor pressure, leading to cavitation. This causes loud metallic noise and can erode honeycomb pits into the gear chambers and gear teeth, reducing volumetric efficiency.

• When Replacing High-Displacement Configurations Like the HGP-2A-F25R, Check the Alignment and Axial Clearance of the Shaft Coupling: External gear pumps are not designed to handle external axial loads or radial misalignment. Misalignment between the pump and motor shaft (recommended within $\le 0.05\text{ mm}$), or hard bottoming of the shafts without axial clearance, will exert side forces on the internal DU bushings. This can cause early shaft seal leaks or shaft fatigue failure over time.