Marzocchi pumps GHP2A-D-22-FG,GHP3A-D-55-FG

General Introduction

1. Model Nomenclature Explanation

1.1 GHP2A-D-22-FG Model Nomenclature

• GHP: High-pressure external gear pump series, designed for continuous high-pressure operation (up to 250 bar), with superior pressure resistance and long service life compared to standard-pressure series.
• 2A: Size group (GHP2), displacement range 11–40 cm³/rev, optimized gear tooth profile to reduce pulsation and noise, suitable for medium-flow high-pressure systems.
• D: Flange mounting, rigid installation with minimal vibration, adopting European standard 4-hole interface for strong compatibility.
• 22: Displacement code (theoretical displacement = 21.8 cm³/rev).
• FG: Special options –F = integrated pressure relief valve (overload protection, preventing system damage caused by excessive pressure); G = mechanical seal (high-pressure, leak-proof, temperature resistance up to 120℃, service life over 5000 hours).

1.2 GHP3A-D-55-FG Model Nomenclature

• GHP: High-pressure external gear pump series, dedicated to high-pressure industrial scenarios, with axial compensation technology to reduce internal leakage under high pressure.
• 3A: Size group (GHP3), displacement range 41–70 cm³/rev, large flow output, strong load-bearing capacity, suitable for large-flow high-pressure hydraulic systems.
• D: Flange mounting, stable installation structure, able to withstand high torque and vibration during high-speed operation.
• 55: Displacement code (theoretical displacement = 54.7 cm³/rev).
• FG: Special options – F = pressure relief valve (automatic pressure adjustment, ensuring stable system pressure); G = mechanical seal (high-temperature and high-pressure resistance, reliable sealing performance across the entire operating temperature range).

2. Basic Information

3. Key Technical Specifications

4. Material & Construction

GHP2A-D-22-FG

• Body/Covers: High-strength aluminum alloy, die-cast, reinforced flanges for high-pressure rigidity, good thermal dissipation performance, suitable for long-term high-load operation.
• Gears: Case-hardened alloy steel, precision-ground, optimized tooth profile to reduce pulsation and noise, minimal backlash, low internal leakage, ensuring high volumetric efficiency.
• Bearings: Bronze bushings with pressure-compensation, high load capacity, strong wear resistance, adapting to high-pressure working conditions.
• Seals: Mechanical seal (G) + FKM washers, leak-proof under 250 bar continuous pressure, reliable sealing performance across -10°C to +100°C temperature range.

GHP3A-D-55-FG

• Body/Covers: High-strength aluminum alloy, thickened structure, reinforced flanges, strong pressure resistance, effectively reducing deformation under high pressure, ensuring stable operation.
• Gears: High-hardness alloy steel, precision hobbing and grinding, large tooth width, strong load-bearing capacity, low noise, suitable for large-flow high-pressure transmission.
• Bearings: High-load roller bearings with pressure-compensation, strong impact resistance, long service life, adapting to high-speed and high-load working conditions.
• Seals: High-pressure mechanical seal (G) + FKM gaskets, excellent sealing performance, able to withstand peak pressure of 300 bar, preventing oil leakage in harsh working environments.

5. Shaft & Mounting Dimensions

GHP2A-D-22-FG

• Shaft: Taper 1:8, key 6×6 mm, thread M16×1.5, high-strength alloy steel, heat-treated, strong torque-bearing capacity.
• Shaft Ø: 22 mm; shaft length: 45 mm; pilot Ø: 55 mm.
• Mounting: 4-hole flange, bolt circle Ø110 mm, M8 bolts, compatible with standard European flange interfaces.
• Max torque: 420 Nm; tightening torque: 80±5 Nm.

GHP3A-D-55-FG

• Shaft: Taper 1:8, key 8×8 mm, thread M20×1.5, high-strength alloy steel, surface hardening treatment, wear-resistant and corrosion-resistant.
• Shaft Ø: 28 mm; shaft length: 50 mm; pilot Ø: 65 mm.
• Mounting: 4-hole flange, bolt circle Ø130 mm, M10 bolts, stable mounting, able to withstand high vibration during operation.
• Max torque: 850 Nm; tightening torque: 100±5 Nm.

6. Port Specifications

7. Product Features

Common Features

• High Efficiency: Precision gear sets, low internal leakage, axial gap compensation technology, consistent output flow and pressure, high volumetric efficiency.
• Low Noise: Optimized gear meshing, rigid body structure, reduced pulsation and vibration, low noise during operation, suitable for noise-sensitive environments.
• Overload Protection: Integrated pressure relief valve (F) automatically releases pressure when system pressure exceeds the rated value, preventing pump and system damage.
• Long Life: High-quality materials, robust bearings and mechanical seals, strict precision processing, long service life, reducing maintenance costs.
• Easy Maintenance: Standardized parts, simple structural design, easy disassembly and assembly, convenient daily inspection and maintenance.

GHP2A-D-22-FG Unique

• Balanced Flow-Pressure: 250 bar continuous pressure + 32 L/min flow, ideal for medium-flow high-pressure hydraulic circuits, balancing performance and energy consumption.
• Low Noise Design: Optimized gear tooth profile and body structure, noise ≤70 dB(A), suitable for industrial environments with strict noise requirements.
• Compact Structure: Medium size, small footprint, easy to install in limited space, strong compatibility with various hydraulic systems.

GHP3A-D-55-FG Unique

• Large Flow Output: 81 L/min flow @1500 rpm, suitable for large-flow high-pressure hydraulic systems, meeting the needs of heavy-duty equipment.
• High Load Capacity: Thickened body, high-load bearings and gears, able to withstand long-term high-pressure and high-load operation, strong reliability.
• Wide Adaptability: High-temperature and high-pressure resistance, compatible with various industrial hydraulic oils, suitable for harsh working environments such as construction and heavy industry.

8. Application Fields

GHP2A-D-22-FG

• Industrial hydraulic systems (injection molding machines, hydraulic presses, clamping units)
• Mobile equipment (medium-sized lifts, agricultural machinery, engineering vehicle attachments)
• Test benches and precision hydraulic control systems
• High-pressure auxiliary circuits and medium-flow hydraulic power units

GHP3A-D-55-FG

• Large-scale industrial hydraulic power units
• Heavy construction machinery (excavators, loaders, cranes)
• Heavy-duty machine tools (large presses, forging machines)
• Mining machinery and material handling equipment
• Large-scale factory automation and high-flow hydraulic systems

9. Installation Instructions

General Requirements

• Mount on a rigid base; align motor-pump shaft (coaxiality ≤0.1 mm) to avoid vibration and reduce wear, it is recommended to use flexible coupling if there is misalignment.
• Suction line: tight seals, no air leakage (to prevent cavitation), diameter ≥ pump inlet, length ≤1.5 m, suction height ≤500 mm, oil suction resistance should not be too high.
• Use clean, filtered hydraulic oil (ISO 4406 cleanliness class 18/15 or better, oil cleanliness ≤NAS 1638-9), viscosity 15–100 cSt (ISO VG), avoid using contaminated or old oil.
• Prime pump before first start: fill inlet chamber and suction line with oil to prevent dry running, which may damage gears and seals.
• The fuel tank should be equipped with a partition to separate bubbles and dirt brought by the return oil; the return oil pipe should extend below the oil level (not directly connected to the pump inlet) to prevent bubbles caused by return oil splashing.

GHP2A-D-22-FG (Flange Mounting)

• Secure flange with 4×M8 bolts, torque 80±5 Nm, ensure firm mounting without looseness.
• Connect suction/pressure lines; use bonded seals to prevent leaks, ensure pipeline connection is smooth without stress.
• Rotate shaft manually for 2–3 turns to confirm smooth rotation, no jamming or abnormal noise.

GHP3A-D-55-FG (Flange Mounting)

• Secure flange with 4×M10 bolts, torque 100±5 Nm, check bolt tightness after initial operation.
• Ensure proper alignment between motor and pump, use flexible coupling to absorb vibration and compensate for slight misalignment.
• Check all connections (flange, pipeline, valve port) for tightness before startup, especially the suction line to prevent air ingestion.

10. Operation Instructions

• Before startup: check oil level (ensure it is within the standard range), vent air from the hydraulic system, open all valves to avoid pressure buildup.
• Idle run: operate at low pressure (<50 bar) for 2–3 minutes; check for abnormal noise, oil leaks, and housing temperature (should not rise rapidly).
• Gradually increase pressure to the working level; confirm that the relief valve functions correctly (automatically releases pressure when exceeding the rated value).
• Operating limits: do not exceed the maximum pressure (300 bar peak) and maximum speed (3600 rpm for GHP2A-D-22-FG, 3000 rpm for GHP3A-D-55-FG); monitor housing temperature (≤100°C).
• Shutdown: reduce the system load to zero, stop the motor, close the isolation valves, and release residual pressure in the pipeline.

11. Maintenance & Troubleshooting

Routine Maintenance

• Oil change: Every 2000 operating hours; replace the filter element at the same time, check the oil quality regularly (if it turns black or has impurities, replace it immediately).
• Seal check: Every 1000 operating hours; check the mechanical seal and gaskets for leaks, replace them if worn or damaged (mechanical seal service life is over 5000 hours under normal use).
• Bolt torque: Re-tighten mounting and port bolts every 500 hours to prevent looseness caused by vibration.
• Inspection: Check gear and bearing wear every 3000 hours; check the relief valve for blockage or failure, and clean or repair it in time.
• Oil contamination check: Check the oil contamination degree every 500 hours to ensure it meets the standard requirements.

Common Faults & Solutions

12. Notes

• Parameters apply to standard configurations; custom specs (such as rotation direction, seal type) may vary, please refer to the order confirmation document.
• Do not operate outside the rated pressure and speed limits, otherwise it will cause serious damage to the pump and shorten its service life.
• Use the recommended hydraulic oil; avoid using contaminated, water-containing or expired oil to prevent corrosion of seals and wear of gears.
• Disconnect the power supply and relieve all system pressure before maintenance to avoid safety accidents.
• Store the pump in a dry, cool and ventilated place; seal the inlet and outlet ports to prevent dust and impurities from entering.
• For unresolved faults or maintenance needs, contact Marzocchi official service or authorized agents, and provide the pump model and serial number.
• The pump can be installed in any direction (horizontal placement), and the shaft end should be installed horizontally with an inclination angle ≤5°.

13. Warranty Information