A4VSO180DR/30R-FPB13N00 A4VSO A4VSO125 A4VSO180 A4VSO250 Hydraulic Piston Variable Displacement Oil Pump

I. Technical Parameters
Core performance parameters
– Pump type: Swash plate axial piston variable pump, electro-hydraulic proportional variable structure, suitable for high-pressure and heavy-load hydraulic systems, supporting independent operation of a single pump or parallel expansion of two pumps.
– Pressure rating: Rated working pressure 31.5 MPa, continuous operating pressure ≤31.5 MPa; The instantaneous peak pressure is 35 MPa (lasting for ≤3 seconds). The back pressure at the return oil port is allowed to be ≤2.5 MPa. In case of overpressure, a relief valve should be configured for protection.
– Displacement and rotational speed: Rated displacement 180 mL/r (corresponding to the “180” mark on the model); Rated speed: 1500 r/min, maximum speed: 2000 r/min (short-term continuous ≤1 minute); The speed adaptation range is 800-1800 r/min, and the flow rate is linearly matched with the speed (the rated flow rate is approximately 270 L/min at 1500 r/min).
– Efficiency and power: Under rated working conditions, the volumetric efficiency is ≥93%, and the total efficiency is ≥88%. When the speed is 1500 r/min, the input shaft power should be ≤140 kW. It is recommended to choose a motor power of 160-185 kW for the matching.
2. Structure and connection parameters
– Structural type: Horizontal installation, swashplate drive plunger layout, integrated electro-hydraulic proportional variable mechanism, pressure shut-off valve and constant power regulation device, adopting a combined pressure lubrication and splash lubrication method.
– Core material: The plunger is made of 42CrMo alloy steel (nitrided, surface hardness HV900-1100); The swash plate is made of QT600-3 ductile iron (surface quenched + precision ground). The cylinder block is made of 35CrMo forged steel (quenched and tempered). The seal is made of high-pressure resistant polytetrafluoroethylene composite material (with a temperature resistance range of -30℃ to 130℃).
– Connection specifications: The diameter of the oil suction port (S port) is Φ 70mm, and the diameter of the oil pressure port (P port) is Φ 60mm. Both are metric threads (M80×2/M72×2). The flange installation is compatible with the ISO 7005-1 standard, and the input shaft is splined (splined specification 32×6).
3. Medium and Environmental requirements
– Medium requirements: It is recommended to use L-HM 46 anti-wear hydraulic oil. For low-temperature environments (below -30℃), L-HV 46 anti-wear hydraulic oil should be selected. The kinematic viscosity of the oil is 20-500 mm²/s, and the moisture content is no more than 0.05%.
– Cleanliness standard: The oil cleanliness must reach ISO 4406 16/13 grade. The system must be equipped with a 5 μm fine filter and a 100 μm coarse filter in front of the oil suction port.
– Environmental parameters: Operating environment temperature -30℃ to 85℃, relative humidity ≤98% (short-term condensation is allowed); With a protection grade of IP67, it is suitable for dust, mud water and high-vibration working conditions of construction machinery and mining equipment.Ii. Working Principle
This pump is a swashplate axial piston variable pump. Its core converts mechanical energy into hydraulic energy through the mechanism of “swashplate driving the piston to reciprocate → volume change for oil suction and discharge → variable mechanism for flow regulation”. The specific process is as follows:
1. Basic oil suction and discharge process
The motor drives the input shaft to rotate the cylinder block. Inside the cylinder block, 10 plungers are tightly attached to the surface of the swash plate through the sliding shoes under the action of the return spring. When the plunger rotates with the cylinder body to the “suction zone”, the inclined surface of the swash plate causes the plunger to extend outward, expanding the volume of the plunger cavity to form a vacuum, and the hydraulic oil is sucked in through the suction port. When rotating to the “oil pressure zone”, the swash plate squeeges the sliding shoe to push the plunger to retract inward, reducing the volume of the plunger cavity. The oil is then pressurized to the rated pressure and discharged from the oil pressure port, achieving a continuous oil suction and discharge cycle.
2. Variable adjustment and safety protection
– Variable adjustment: By inputting a 4-20 mA control signal through the electro-hydraulic proportional valve, the control pressure of the variable mechanism (1.0-4.5 MPa) is adjusted to change the tilt Angle of the swash plate. When the tilt Angle increases, the plunger stroke increases, and the pump displacement increases accordingly (up to 180 mL/r). When the tilt Angle is reduced, the displacement decreases (minimum 18 mL/r), achieving stepless adjustment of flow rate from 0 to 100%.
– Safety protection: Built-in pressure shut-off valve and constant power regulation device. When the system pressure exceeds 31.5 MPa, the shut-off valve automatically reduces the inclination Angle of the swash plate to limit the flow rate. When the input power approaches the rated value, the constant power device limits power overload by reducing the displacement, providing dual protection to ensure system safety.

Iii. Product Features and Advantages
– Strong adaptability to high pressure and heavy load: With a rated pressure of 31.5MPa, it can be adapted to various heavy-duty hydraulic systems. With a rated flow rate of 270L /min (1500r /min), it can drive multiple actuators to perform compound actions, such as the synchronous operation of excavators for digging, rotating, and walking, meeting the requirements of high-intensity operations.
– Wear-resistant, fatigue-resistant and long service life: After nitriding treatment, the surface hardness of the plunger is high, which is wear-resistant and anti-seizing. The swash plate adopts precision grinding technology, with a surface roughness Ra≤0.2 μm. The sliding shoe is equipped with an internal self-lubricating structure. Under rated working conditions, the fault-free operation life can reach 15,000 hours, which is more than 20% longer than that of ordinary plunger pumps.
– High variable energy-saving efficiency: Supports 10-100% stepless flow adjustment, can match the output flow in real time according to the load, operates at a small flow rate under light load to reduce energy consumption, and saves 30-40% energy compared with fixed displacement pumps. Constant power regulation further optimizes power distribution and is suitable for intermittent or continuous heavy-load operations.
– Good adaptability to extreme working conditions: The IP67 protection grade can effectively prevent mud, water and dust from entering. It starts smoothly in a low-temperature environment of -30℃ and maintains stable sealing performance at a high temperature of 85℃, making it suitable for extreme operation scenarios such as high-cold mines and high-temperature metallurgy.
– Stable, reliable and easy to maintain: Equipped with dual protection of pressure cut-off and constant power to prevent damage from overpressure or power overload. The modular cylinder block design allows for the replacement of vulnerable parts such as the plunger and sliding shoe by removing the front end cover. The maintenance time is no more than 2 hours, and the parts have strong universality.

Iv. Usage Functions and Purposes
1. Core usage functions
– High-pressure and high-flow oil supply: It provides a stable oil source for high-pressure hydraulic systems. With a pressure of 31.5 MPa and a flow rate of 270 L/min, it can meet the power requirements of multiple actuators in heavy equipment, ensuring the stable execution of heavy-load actions.
– Precise flow regulation: The flow is steplessly controlled through a 4-20mA signal. When the load is light (such as when the equipment is running empty), the flow is reduced to save energy. When the load is heavy (such as in hard rock excavation), the full flow is used for power transmission, making it suitable for scenarios with large load fluctuations.
– Multiple safety protections: The pressure shut-off valve prevents overpressure, the constant power device prevents overload, and it integrates an oil temperature alarm interface for excessive heat, providing all-round protection for the pump body and pipelines and reducing the risk of failure.
– Parallel expansion adaptation: Supports two pumps operating in parallel, achieving an ultra-high flow output of 540 L/min. Through synchronous control, it ensures uniform flow distribution, making it suitable for large-scale hydraulic system upgrade scenarios.
2. Main application fields
– Construction machinery: Main hydraulic system for 30-40 ton excavators, lifting and drive system for 20-25 ton loaders, lifting and luffing system for 15-20 ton crawler cranes.
– Mining and metallurgical equipment: Propulsion systems for medium-sized mine roadheaders, downward systems for small-scale metallurgical rolling mills, and hydraulic drive systems for large-scale mine crushing stations.
– Industrial and special equipment: Clamping and injection systems for 1000-1500 ton injection molding machines, hydraulic systems for heavy forging equipment, main drive systems for shield machines with a diameter of ≥3 meters.

V. Applicable Machines and Scenarios
1. Adapt to the core machine
– Construction machinery: 30-40 ton crawler excavators, 20-25 ton wheel loaders, 15-20 ton crawler cranes.
– Mining and metallurgical equipment: Medium-sized mining tunnel boring machines, small metallurgical rolling mills, large-scale mining crushing stations.
– Industrial equipment: 1000-1500 ton injection molding machines, heavy-duty forging presses, shield machines with a diameter of ≥3 meters.
2. Typical application scenarios
– Application of the main pump for excavators: As the main hydraulic pump for 35-ton excavators, it outputs 31.5 MPa pressure oil to drive the three major actions of excavation, rotation and walking. With a flow rate of 270 L/min at 1500 r/min, it ensures the synchronous and smooth operation of the compound actions. When driving without load, the flow rate drops to 60 L/min, significantly reducing fuel consumption and making it suitable for scenarios such as hard rock excavation in mines and earthwork excavation in infrastructure.
Injection drive for injection molding machine: It supplies fuel to the injection system of a 1200-ton injection molding machine. During the injection stage, the flow rate is fully opened (270 L/min) to achieve rapid advancement (speed ≥0.6 m/s). During the pressure-holding stage, the flow rate is reduced to 25 L/min to stabilize the pressure, improving the forming accuracy of large plastic parts (error ≤0.5%), and is suitable for batch forming scenarios of automotive bumpers and home appliance shells.
– Roadheader drive scenario: It supplies fuel to the propulsion and cutting system of medium-sized mine roadheaders. With a pressure of 30 MPa and a flow rate of 250 L/min, it drives the cutting head to rotate and break rocks. The propulsion speed can be steplessly switched from 0.1 to 0.5 m/min through flow rate adjustment, making it suitable for tunneling and underground engineering excavation scenarios in mines.

Six. Similar models
1. Alternative models of the same series
-A4VSO140DR /30R-FPB13N00: This small-displacement model of the same structure has a rated displacement of 140 mL/r (with a flow rate of approximately 210 L/min at 1500 r/min), a rated pressure of 31.5 MPa, and the installation dimensions are the same as the original model. It is suitable for excavators of 25-30 tons and the cost is 20% lower than that of the original model.
-A4VSO250DR /30R-FPB13N00: The large-displacement model of the same series has a rated displacement of 250 mL/r (with a flow rate of approximately 375 L/min at 1500 r/min), a rated pressure of 31.5 MPa, and the structural material is the same as the original model. It is suitable for excavators of 40-50 tons, but the cost is 25% higher than that of the original model.
2. Cross-series alternative models
-A4VSO180EP /30R-FPB13N00: A high-pressure upgraded model with a rated pressure of 40 MPa and a displacement of 180 mL/r. The surface of the plunger and swash plate is coated with ceramic, enhancing wear resistance by 50%. It is suitable for heavy-duty mining hammer systems and has a 45% higher cost than the original model.
-A4VSO180EO /30R-FPB13N00: A simplified model with a fixed displacement, a displacement of 180 mL/r, a rated pressure of 31.5 MPa, no variable adjustment mechanism, a more compact structure, suitable for scenarios with stable loads (such as fixed-speed heavy-duty conveyors), and a cost 35% lower than the original model.
-A4VSO180DR /30R-FPB13N01: Dual-pump model with a total displacement of 360 mL/r (180+180 mL/r), rated pressure of 31.5 MPa, suitable for dual-circuit independent oil supply systems (such as the main system of the excavator + the linkage of the breaker), and the cost is 65% higher than that of the original model.

Vii. Precautions for Use
1. Oil management
– Only L-HM 46 or L-HV 46 anti-wear hydraulic oil must be selected. It is strictly prohibited to mix different grades and types of oil. The oil of the new pump must be changed after its first 500 hours of operation. Subsequently, the oil should be changed every 1,500 hours. Before changing the oil, the oil tank, pipelines and two-stage filters must be thoroughly cleaned.
Check the oil level and cleanliness every week. Replace the filter element immediately when the pressure difference of the fine filter exceeds 0.5 MPa and that of the coarse filter exceeds 0.3 MPa. When the oil is found to be emulsified, discolored (brown or black), or containing metal debris, the system should be thoroughly disassembled and cleaned, and the oil changed to prevent abnormal wear of the plunger and swash plate.
2. Installation and commissioning
When installing, the coaxiality error between the pump shaft and the motor shaft should be no more than 0.1mm (for rigid connection) or no more than 0.2mm (for elastic connection), the flatness of the flange surface should be no more than 0.03mm /m, and the connecting bolts should be evenly tightened with a torque of 800 N·m to prevent eccentric installation from causing the bearing to overheat.
Before the first start-up, fill the pump body with hydraulic oil through the oil filling hole at the top. Manually turn the pump by hand for 8 to 10 turns to ensure smooth rotation. After starting, run it unloaded for 20 minutes (at a speed of 1000 r/min). When the oil temperature rises above 40℃, gradually load it. The pressure increase rate should be no more than 0.5 MPa/ minute to avoid cold start shock.
When debugging the variable mechanism, test the flow linearity within the 4-20 mA control signal range to ensure that the flow deviation is ≤±2%. Calibrate the pressure shut-off valve and the constant power device to ensure that the protection is precisely triggered when the pressure reaches 31.5 MPa and the power approaches the rated value.
3. Operation and Maintenance
During operation, real-time monitoring of the pump body temperature (normal ≤80℃, maximum ≤85℃), inlet and outlet pressures, and vibration values (≤ 5.0mm /s) is conducted. If a sudden temperature rise of ≥10℃, pressure fluctuation > 1MPa, or abnormal noise is detected, the machine should be immediately shut down to check for oil cleanliness, plunger wear, or jamming of the variable mechanism.
– Regular maintenance every 3,000 hours: Replace seals, plunger sliders and two-stage filter elements; Check the surface wear of the swash plate (wear > 0.05mm requires grinding and repair) and the wear of the splined shaft (wear > 0.08mm requires replacement). Disassemble and inspect the cylinder block every 10,000 hours. Replace the cylinder block or variable mechanism components if necessary.
Before starting after long-term parking, disassemble the variable mechanism to check if the valve core is stuck, and apply special grease to the gap between the plunger and the cylinder block. Heat the oil to above 10℃ before starting at low temperatures (< -10℃) to avoid cold start wear.
4. Storage protection
When stored for a long time, seal the oil suction port and the oil pressure port with metal plugs, inject anti-rust oil into the pump body (90% of the shell volume), apply anti-rust grease to the splines of the output shaft, and wrap the entire pump with a waterproof and dustproof cover. Store in a dry and well-ventilated place (0-40℃, humidity ≤60%). Manually turn the machine 3 times a month to prevent adhesion and rust.
Before the pump is put into use after being idle for more than 12 months, thoroughly clean the interior of the pump body and replace all the seals. Test the flexibility of the variable mechanism with low-pressure oil (2-3 MPa). After installation, load it in stages to 50%, 75%, and 100% of the rated pressure respectively. Run each stage for 30 minutes to confirm normal operation before putting it into use.