Rexroth HG Series Internal Gear Pump Replacement | HG2-80-01R-VPC

Genlu Hydraulic excels as a world-class engineered fluid power component manufacturer, precision internal gear profile casting specialist, and strategic B2B global supplier of high-pressure, ultra-low-noise hydraulic pumps and modular electro-hydraulic servo power sources. The HG Series High-Pressure Fixed Displacement Internal Gear Pump Platform (encompassing definitive modular frame sizes HG0, HG1, and HG2, and emphasizing primary field replacement code HG2-80-01R-VPC) is custom-engineered and manufactured as a premium, structurally reinforced, and 100% drop-in interchangeable high-tier alternative to the definitive global industry standard—the Bosch Rexroth HG series internal gear pumps. We manage modern multi-axis CNC production cells and retain complete quick-ship warehouse inventory for high-frequency replacement specifications, including smaller frames like HG1-25, HG1-32, HG1-40, HG1-50, HG1-63 as well as large-capacity modules like HG2-80, HG2-100, HG2-125, and HG2-160, ensuring global industrial machinery fleets achieve plug-and-play retrofitting without any hard-piping modifications.

Operating as the primary pressure-generating core for high-precision CNC machine tool drives, variable-speed plastic injection molding machines, and heavy metal-forming presses, an internal gear pump must withstand continuous high-pressure loading (nominal 210 bar to 250 bar, with transient peaks up to 315 bar) and rapid acceleration/deceleration cycles under servo motor control without suffering from volumetric efficiency drop or external seal blowouts. Genlu’s Rexroth-style HG series gear pumps conform directly to the precise geometric and material tolerances specified in original factory technical manuals. We guarantee perfect drop-in compatibility across standard SAE mounting pilots, cylindrical straight keyed drive shafts, split-flange fluid working port patterns, and the internal hydrostatic radial and axial pressure-balanced gap compensation assembly. Prior to final warehouse dispatch release, every single pump assembly undergoes 100% Full-Simulation Condition Testing on digitized diagnostic stands to verify that volumetric efficiency remains above 95% under maximum pressure and thermal loading while keeping airborne acoustic noise within strict environmental limits.

Technical Specifications

• Product Line: HG Series (HG0 / HG1 / HG2) High-Pressure Fixed Displacement Internal Hydraulic Gear Oil Pump (100% cross-compatible with Bosch Rexroth HG criteria)

• Core Covered Specific Configurations & Coding Mapping:

  • HG1 Volume Segment: HG1-25 / HG1-32 / HG1-40 / HG1-50 / HG1-63

  • HG2 Volume Segment: HG2-80 / HG2-100 / HG2-125 / HG2-160

  • Detailed Summary Configuration (e.g., HG2-80-01R-VPC: HG2 designates the heavy-duty medium-to-large capacity internal gear frame; 80 signifies an 80.0 cc/rev nominal geometric displacement; 01 denotes standard cylindrical straight keyed drive shaft integrated with a standard SAE 2-bolt mounting flange; R indicates Clockwise/Right-hand rotation; V represents premium Fluororesin (FKM) seals, suitable for phosphate esters and mineral oils; PC represents factory-defined heavy-duty high-pressure fluid port threading layout)

• Geometric Displacement Matrix Range:

  • HG1 Frame Matrix: From 25.0 $cc/rev$ up to 63.0 $cc/rev$

  • HG2 Frame Matrix: From 80.0 $cc/rev$ up to 160.0 $cc/rev$ (This model offers precisely 80.0 $cc/rev$)

• Continuous Rated Operating Pressure Boundaries: 210 bar to 250 bar (21 MPa – 25 MPa) continuous duty loading envelope

• Maximum Intermittent Intermittent Peak Pressure Bound: Rated up to 315 bar (31.5 MPa / 4560 psi) resisting abrupt fluid relief overshoots

• Permissible Operational Rotational Speed Velocity Range: From 600 rpm up to 3000 rpm (Engineered to support low-speed, high-torque holding cycles in energy-saving servo systems)

• Rotational Direction Dynamic Profile: R-code designating standard Clockwise single-direction rotation when looking at the shaft journal face

• Primary Structural Metallurgy: Integrated monolithic forged alloy steel drive gear shaft matched with a high-tensile ductile iron housing and specialized bimetal composite internal components

• Total Pump Assembly Dry Mass: Approximately 24.5 kg (For the HG2-80 specification, utilizing a rigid compact casing design)

Key Technical Advantages:

• Hydrostatic Two-Way Radial and Axial Clearance Compensation: The HG2 pump incorporates advanced axial thrust plates combined with a radial floating sealing shoe mechanism within the crescent zone, actively powered by internal high-pressure fluid micro-channels. This hydrostatic sealing system dynamically tightens internal micro-gaps as the system ramps up to 250 bar. This configuration minimizes internal fluid bypass and maintains a volumetric efficiency above 95% across its entire service life.

• Straight-Line Conjugate Tooth Profile for Ultra-Low Airborne Noise: The internal pinion and ring gear group feature a straight-line conjugate profile. During high-speed tooth engagement, fluid contact lines transition smoothly, avoiding the fluid trapping and localized pressure spikes typical of external gear designs. This smooth operation eliminates fluid-borne whistling and keeps full-load operating noise around 65 dB, making it suitable for noise-sensitive factory environments.

• High Tooth Contact Ratio to Minimize Output Pressure Pulsations: Due to the concentric geometry of the internal gear setup, multiple teeth engage simultaneously, lowering output flow pulsations below 1%. This consistent flow delivery prevents downstream hydraulic line resonance, supporting control stability and response stiffness in precision CNC machinery and servo-driven stamping presses.

• Heavy-Duty Hydrostatic Journal Bearings for High Overload Resistance: The drive shaft is supported by large-scale, low-maintenance journal bearings featuring a specialized alloy overlay. These bearings rely on system fluid to create a non-contacting hydrostatic film that minimizes friction. This structural layout provides reliable shaft support, preventing uneven wear, scoring, or shaft fatigue even during high-frequency pressure spikes up to 315 bar under servo control.

Application Areas:

• Precision CNC Machine Tools & Advanced Plastic Processing Machinery: High-precision CNC press brakes, variable-speed energy-saving servo injection molding platforms, and heavy-duty rubber vulcanizing presses.

• Heavy Hydraulic Iron Presses & Metal Cutting/Forming Equipment: Main pressure holding pumps for large four-column stamping presses, heavy industrial scrap metal balers, and auxiliary power units for high-frequency sheet metal stamping lines.

• Industrial Automation Workstations & Centralized Fluid Lubrication Skids: Primary power source for automated manufacturing lift tables and electro-hydraulic servo proportional valve control blocks in heavy metallurgical mills.

Expert Maintenance Tips:

• Mandatory Pre-Lubrication and Shaft Rotation Prior to Initial Commissioning: Internal gear pumps utilize tight internal clearances that are highly sensitive to dry running at startup. Before initial commissioning or after extended storage, fill the pump housing with clean hydraulic fluid through the intake port and manually rotate the input shaft several turns to establish a protective oil film on the gear faces and thrust plates. Avoiding dry running prevents localized scoring of the internal wear components.

• Verify Vacuum Tightness of the Intake Line to Prevent Cavitation Pitting: Because HG series pumps frequently run at high speeds under servo motor control, any minor leakage or loose hose clamps along the intake line can introduce air into the negative-pressure intake loop. This air ingestion causes cavitation pitting and localized overheating, characterized by a metallic “clicking” noise and output pressure fluctuation. Maintain a suction vacuum within -0.3 bar and inspect all intake seals regularly.

• Adhere to Stringent Fluid Filtration and Hydraulic Oil Cleanliness Standards: The internal pressure-balanced compensation mechanisms require clean oil to prevent particle scoring. When replacing a worn original pump (such as an old HG2-80-01R-VPC), fine debris from the failure remains trapped in the system. Before starting the new pump, drain and flush the reservoir, replace the return elements, and install high-pressure filtration rated at $\le$ 10 $\mu m$, maintaining a fluid cleanliness standard of ISO 4406 18/15 or NAS 7.