Detailed Parameter Description of ALP1A-D-2-FG Gear Pump

1. Model Nomenclature Explanation

• ALP: Identifies the product series, representing the standard pressure hydraulic gear pump series of Marzocchi, which is distinguished from the high-pressure GHP series and low-noise ELIKA series.
• 1A: Indicates the size group, belonging to Group 1 of the ALP series. This group determines the basic installation dimensions, structural size, and maximum displacement range of the pump, making it suitable for compact hydraulic systems.
• D: Specifies the installation method, referring to flange mounting. This installation mode ensures stable connection with the hydraulic system, reduces vibration during operation, and facilitates disassembly and maintenance.
• 2: Represents the displacement parameter, with a nominal displacement of 1.4 cm³/rev (cubic centimeters per revolution), which directly determines the flow output capacity of the pump under a certain rotational speed.
• FG: Denotes special configuration options, where “F” stands for a built-in pressure relief valve to protect the pump and the entire hydraulic system from overpressure damage, and “G” indicates a standard mechanical seal for reliable sealing performance.

2. Core Technical Parameters

2.1 Displacement and Flow Rate

• Nominal Displacement: 1.4 cm³/rev (1.4 cc/rev)
• Flow Rate at 1500 rpm: 2.0 L/min (liters per minute). The flow rate is proportional to the rotational speed within the rated range, and the actual flow output may vary slightly with changes in system pressure and oil viscosity.

2.2 Pressure Ratings

• Maximum Continuous Operating Pressure: 250 bar (25 MPa). This is the maximum pressure that the pump can withstand during long-term continuous operation without damage.
• Maximum Intermittent Pressure: 270 bar (27 MPa). This refers to the maximum pressure that the pump can bear for short periods (intermittent operation) during peak working conditions.
• Peak Pressure: 290 bar (29 MPa). This is the maximum instantaneous pressure that the pump can withstand in emergency or short-term extreme working conditions, and long-term operation at this pressure is not recommended to avoid shortening the service life.
• Inlet Pressure: 0.7 – 3 bar, ensuring stable oil suction and preventing cavitation damage to the pump core components.

2.3 Rotational Speed

• Minimum Operating Speed: 800 rpm, ensuring sufficient oil suction and stable hydraulic output at low speeds.
• Maximum Operating Speed: 6000 rpm, which is the upper limit of rotational speed that the pump can bear, beyond which the pump may experience excessive wear and reduced service life.
• Recommended Operating Speed Range: 1000 – 2000 rpm. Within this range, the pump achieves the optimal balance of efficiency, noise, and service life, with a volumetric efficiency of up to 93%.

2.4 Working Medium and Environmental Conditions

• Recommended Working Medium: Hydraulic oil with a viscosity range of 6 – 500 cst; the optimal viscosity for startup and stable operation is 10 – 100 cst, which ensures good lubrication and fluidity.
• Operating Temperature Range: -10°C to +80°C. The pump can maintain stable performance within this temperature range, adapting to most industrial and outdoor working environments without additional heating or cooling equipment under normal conditions.
• Sealing Material: NBR (nitrile butadiene rubber) seals, which provide excellent oil resistance and sealing performance, effectively preventing oil leakage and ensuring the integrity of the hydraulic system.

3. Structural and Material Parameters

• Pump Body and Covers: Made of high-strength pressure-resistant aluminum alloy through die-casting. This material not only ensures excellent structural rigidity and corrosion resistance but also reduces the overall weight of the pump, making it suitable for installation in compact and lightweight equipment.
• Gear Pair: Crafted from special hardened steel,经过 precision grinding and heat treatment. This ensures high wear resistance, stable tooth meshing, low mechanical noise, and effectively reduces energy loss during operation, while extending the service life of the gear pair.
• Shaft Type: Conical shaft with a 1:8 taper and a 3 mm key (Type T0), with a shaft diameter of 12 mm, a shaft length (including fitting edge) of 35 mm, and a fitting edge diameter of 30 mm. The conical design ensures a tight connection with the drive device, preventing slippage during high-speed operation.
• Flange and Ports: Equipped with a European standard 4-hole mounting flange, complying with SAE J 744 C standards, ensuring compatibility with various hydraulic system installations. The inlet and outlet ports adopt BSPP threaded ports (1/2″ BSP thread), complying with SAE J 1926/1 (ISO 11926-1) standards, facilitating connection with hydraulic pipelines and reducing leakage risks.
• Shaft Load and Tightening Torque: Maximum shaft torque is 100 Nm, and the recommended shaft tightening torque is 50 ± 4 Nm, ensuring stable connection and avoiding damage to the shaft due to excessive torque.

4. Performance Characteristics and Advantages

• High Efficiency: With a volumetric efficiency of up to 93% within the recommended rotational speed range, the pump effectively reduces energy consumption and heat generation, lowering the operating cost of the hydraulic system over the long term.
• Low Noise: The optimized gear tooth profile and precision manufacturing tolerances minimize fluid pulsation and mechanical vibration, resulting in lower noise emission compared to ordinary gear pumps, improving operator comfort and reducing environmental noise pollution.
• Reliable Sealing: The standard mechanical seal (marked by “G” in the model) and NBR sealing materials ensure zero or minimal leakage, even under high-pressure conditions, maintaining the stability of the hydraulic system pressure.
• Built-in Protection: The integrated pressure relief valve (marked by “F” in the model) automatically releases pressure when the system pressure exceeds the rated value, effectively protecting the pump, pipelines, and other hydraulic components from overpressure damage, enhancing the safety and service life of the entire system.
• Easy Installation and Maintenance: The flange mounting design, standard ports, and compact structure facilitate quick integration into various hydraulic systems, while the simple internal structure makes daily inspection and maintenance convenient, reducing downtime.

5. Application Scope

• Industrial Equipment: Small machine tools, hydraulic shearing machines, shoe-making machinery, plastic injection molding auxiliary equipment, and material handling systems, where it provides stable hydraulic power for precise movements and operations.
• Mobile Equipment: Compact agricultural machinery (such as small tractors and sprayers), small construction machinery (such as mini excavators and loaders), and specialized mobile hydraulic equipment, adapting to the harsh working conditions of outdoor operations.
• Other Fields: Precision hydraulic test equipment, small automation equipment, and light industrial hydraulic systems, where its high efficiency and reliability meet the requirements of long-term stable operation.

6. Quality Assurance and Notes

• The pump should be operated within the rated pressure and rotational speed range to avoid overloading.
• Use hydraulic oil that meets the viscosity requirements, and regularly replace the oil and clean the oil filter to prevent impurities from damaging the gear pair and seals.
• Check the sealing performance regularly. If oil leakage is found, replace the seals in a timely manner.
• During installation, ensure the flange connection is tight and the shaft alignment is accurate to avoid vibration and wear caused by misalignment.