Rexroth H1125W01480 Vane Pump GXM0-A0C25CF-21

Rexroth H1125W01480 (GXM0-A0C25CF-21) Hydraulic Vane Pump

The Bosch Rexroth H1125W01480 (Type Code: GXM0-A0C25CF-21) is a heavy-duty, fixed-displacement intra-vane hydraulic pump engineered specifically for medium-to-high pressure industrial power units and rigorous marine deck applications. Utilizing a balanced-vane cartridge configuration, this unit neutralizes internal radial hydraulic bearing loads, significantly reducing shaft fatigue and extending continuous-duty operational life under cyclic loading conditions.

Its design delivers a geometric displacement of 25.0 cm³/rev (1.53 in³/rev) with peak operating pressures up to 210 bar (3050 psi). The precision-ground rotor and hardened intra-vane geometry ensure high volumetric and mechanical efficiency across a standard speed range of 600 to 1800 RPM. Designed to meet demanding offshore, propulsion-adjacent, and factory-automation hydraulic demands, the GXM0-A0C25CF-21 maintains ultra-low airborne and fluid-borne noise signatures—a critical attribute for closed shipboard spaces such as steering gear compartments and auxiliary machinery rooms.

Model Details

• Manufacturer: Bosch Rexroth AG
• Manufacturer Part Number (MPN): H1125W01480
• Rexroth Model Code / Type Code: GXM0-A0C25CF-21
• Displacement Group: Size 0 / 25 cm³/rev
• Series / Revision: 21 Design Series
• Mounting Standard: SAE-B 2-Bolt Flange (ISO 3019-1 / 101-2)
• Shaft Configuration: Cylindrical Keyed Shaft (Standard ISO/SAE keyed, metric/inch standard profile)
• Rotation Direction: Clockwise (Right-Hand / CW viewed from shaft drive end)

Features

1. Hydraulically Balanced Cam-Ring & Rotor Design: Opposed suction and pressure ports eliminate net radial hydraulic forces on internal bearings, drastically curbing wear and heat generation under high-pressure duty.
2. Low Noise Acoustic Profile: Precision contour vane tracks deliver a dampened pressure transition, restricting airborne noise emissions below 68 dB(A) at full continuous load.
3. Modular Cartridge Architecture: Core working components (rotor, vanes, cam ring, port plates) are fully contained in a serviceable sub-assembly, enabling rapid dockside or shipboard maintenance without removing the pump casing from the system piping.
4. Wide Thermal and Fluid Compatibility: Operational with standard mineral-based hydraulic oils (HLP/HVLP per DIN 51524), phosphate ester, synthetic esters, and water-glycol fire-resistant hydraulic fluids (HFC) with correct seal compound matching.
5. Dual-Bolt SAE-B Robust Mounting: Standardized flange geometry ensures seamless drop-in mechanical interchangeability with standard marine bellhousings, PTO drives, and IEC/NEMA electric motor adaptors.

Applications

• Marine Steering Gear Power Units (HPU): Serving as primary or emergency auxiliary displacement pumps driving ram-type or rotary-vane rudder actuators.
• Deck Machinery & Mooring Winches: Hydraulic feed systems for cargo cranes, windlasses, capstans, mooring winches, and hydraulic hatch cover actuators.
• Bow Thruster Pitch & Auxiliary Controls: Supplying hydraulic pressure for variable-pitch propeller control hubs and thruster deployment mechanisms.
• Offshore Rig Skidding & Ballast Control: Applied in modular hydraulic packs operating offshore jacking stations, ballast manifold valves, and drill floor handling equipment.
• Industrial Molding & Metalworking Presses: Stationary hydraulic power packs where low pulsations, steady volumetric output, and quiet running are mission-critical.

Compatible Equipment

• Marine Power Packs: Brattvaag, MacGregor, Rolls-Royce/Kongsberg Marine Deck HPUs, Hatlapa, and Ulstein hydraulic steering skids.
• Electric Motor Frames: Directly mounts to IEC 100/112/132 or NEMA 182TC/184TC frames using standard SAE-B bellhousing kits.
• Direct Casing Interchanges: Vickers/Eaton 25V series (cartridge and footprint interchangeability subject to shaft/port flange verification), Denison/Parker T6C series (footprint comparable).

Part Number Cross-References

• Bosch Rexroth: H1125W01480
• Rexroth Type Code: GXM0-A0C25CF-21
• Alternative Marine Spare Code: R900XXXXXX / R902XXXXXX series equivalent (cross-reference verified via physical pump casting stamp)

Frequently Asked Questions

Can the rotation direction of the Rexroth H1125W01480 be converted in the field?

Yes. The GXM0 design enables rotation conversion (from right-hand clockwise to left-hand counter-clockwise) without requiring new external casings. You must disassemble the housing, remove the cartridge kit, flip the cam ring relative to the port plates in accordance with the service manual diagrams, re-index the internal alignment pins, and re-torque the housing bolts to exact OEM torque limits.

What is the exact difference between continuous pressure and peak pressure on this pump?

Continuous pressure (175 bar) designates the maximum continuous working pressure your relief valve should allow during routine duty cycles. Intermittent peak pressure (210 bar) is reserved for momentary dynamic shock loads and transient surges lasting no more than 10% of any given duty cycle, with a maximum transient duration of 1 to 2 seconds.

Which hydraulic fluid viscosity index is best suited for marine steering gear installations?

For vessels operating across variable sea-surface water temperatures, use a high-viscosity-index mineral oil conforming to DIN 51524 Part 3 (HVLP 46 or HVLP 68). Ensure the operational viscosity remains within the ideal 20 to 54 mm²/s band at running oil temperatures (typically 45°C to 55°C).

How often should the internal vane cartridge kit be replaced?

Under disciplined marine operating conditions with clean oil (ISO 4406 Class 18/16/13) and sustained temperatures under 60°C, the GXM0 cartridge carries an expected operational lifespan between 8,000 and 12,000 running hours. Immediate replacement or refurbishment is indicated if case drain/bypass leakage drops pump volumetric efficiency below 80% at rated pressure.