Rexroth hydraulic pump A4VSO series manual
Instruction Manual for Rexroth A4VSO Series Axial Piston Variable Pump
1. Product Description
The Rexroth A4VSO series is an axial piston variable pump with a swashplate design, specifically designed for hydrostatic drives in open-circuit hydraulic systems. The pump’s flow rate is proportional to the drive speed and displacement, and the flow can be infinitely varied by adjusting the swashplate angle, making it suitable for a wide range of industrial and mobile hydraulic applications.
Key Features:
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Excellent suction characteristics for stable operation
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Low noise level, ensuring a comfortable working environment
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Good power-to-weight ratio, saving installation space
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Modular layout, facilitating maintenance and combination with other components
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Short control response times, ensuring precise flow regulation
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Axial and radial load capacity of the drive shaft, enhancing durability
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Possible through drive and pump combinations for flexible system configuration
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Swivel angle indicator for easy monitoring of displacement
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Any installation position possible, adapting to different system layouts
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Suitable for operation with HFC hydraulic fluids (with specific requirements) and mineral oil (without restrictions)
2. Type Code Explanation
The type code of the A4VSO series pump contains key information about its configuration. The following is a detailed explanation of the standard type code structure (specific configurations may vary by series):
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Position
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Code
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Description
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|---|---|---|
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01
|
A4VS
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Axial piston unit, swashplate design, variable displacement, nominal pressure 350 bar, maximum pressure 400 bar
|
|
02
|
O
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Operating mode: Pump, open circuit
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|
03
|
Size (NG)
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Geometric displacement, including 40, 71, 125, 180, 250, 355, 500, 750, 1000 (see technical data for details)
|
|
04
|
Control Device
|
Various options available, e.g., OV (without variable control), DR (pressure controller), FR (flow controller), MA (manual control), EM (electric motor control) (see separate data sheets for details)
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|
05
|
Series
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Series 1 (index 0 or 1) and Series 3 (index 0), with specific applicability to different control devices
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|
06
|
Hydraulic Fluid Version
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No code for mineral oil; E for HFA, HFB, HFC hydraulic fluids; H for high-speed version
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3. Technical Data
The following technical data are general specifications for the A4VSO series. For detailed data of specific models, refer to the order confirmation and technical data sheet RE 92050.
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Parameter
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Specification
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|---|---|
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Nominal Pressure
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350 bar
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Maximum Pressure
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400 bar
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|
Size Range (NG)
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40 to 1000
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|
Operating Viscosity Range
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Refer to technical data sheet RE 92050 for detailed selection diagram and information
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|
Permissible Hydraulic Fluids
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1. Mineral oil (without restrictions); 2. HFC hydraulic fluids (water content approx. 35-55 weight percent, complying with ISO 12922), e.g., Fuchs Hydrotherm 46M, Petrofer Ultrasafe 620, Houghton Houghto Safe 620, Union Carbide HP 5046; 3. Other fluids (contact Bosch Rexroth for confirmation)
|
|
Installation Position
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Any position
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4. Installation Instructions
4.1 Installation Preparation
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Before installation, ensure that the pump is free from damage during transportation. Check the packaging and the pump body for any signs of collision or leakage.
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Prepare the necessary tools and accessories, including mounting bolts, seals, and hydraulic hoses that meet the pressure requirements (minimum pressure rating of 400 bar).
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Ensure the installation surface is clean, flat, and free from burrs. The mounting base should have sufficient rigidity to avoid vibration during pump operation.
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Have the relevant documents on hand, including the order confirmation, installation drawing, and technical data sheet RE 92050.
4.2 Mounting Steps
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Place the pump on the mounting base, align the mounting holes of the pump with those of the base, and ensure the drive shaft is coaxial with the motor shaft (coaxiality error ≤ 0.1 mm/m).
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Fasten the mounting bolts evenly with the specified torque to avoid uneven stress on the pump body.
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Connect the hydraulic hoses to the suction port (S), pressure port (A/B), and leakage oil port (R/L). Ensure the connections are tight and free from leakage; use appropriate seals to prevent oil seepage.
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If the pump is equipped with a through drive, ensure the connection is firm and the coaxiality is maintained.
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Fill the pump and the hydraulic system with the recommended hydraulic fluid to the specified level. Bleed the air from the system to avoid cavitation during operation.
5. Commissioning
Before formal operation, conduct a commissioning test to ensure the pump operates normally. Follow the steps below:
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Check the power supply and motor rotation direction to ensure it matches the pump’s required rotation direction (viewed from the drive shaft, clockwise or counterclockwise as specified by the type code).
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Start the motor at low speed (100-200 rpm) and run it for 2-3 minutes. Observe for any abnormal noise, vibration, or oil leakage.
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Gradually increase the motor speed to the rated speed, and adjust the swashplate angle to check the flow regulation performance. Ensure the flow rate changes smoothly with the swashplate angle.
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Monitor the operating pressure, temperature, and oil level of the system. The normal operating temperature of the hydraulic fluid should be 30-60℃; if the temperature exceeds 70℃, stop the pump and check the system for faults.
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Run the pump continuously for 30-60 minutes under rated conditions. If no abnormalities are found, the commissioning is completed, and the pump can be put into formal operation.
6. Maintenance and Servicing
6.1 Routine Maintenance
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Daily Check: Inspect the pump for oil leakage, abnormal noise, and vibration; check the oil level and temperature of the hydraulic system.
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Weekly Check: Clean the oil filter and check for clogging; inspect the condition of hydraulic hoses and seals.
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Monthly Check: Check the tightness of mounting bolts and connections; inspect the swivel angle indicator for accuracy; sample and test the hydraulic fluid to ensure it meets the required specifications.
6.2 Periodic Servicing
The service cycle depends on the operating conditions and hydraulic fluid quality. Generally, the following servicing work should be performed every 2000-5000 operating hours:
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Replace the hydraulic fluid and clean the oil tank.
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Replace the oil filter element and seals.
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Disassemble the pump and inspect the internal components (pistons, cylinder block, swashplate, bearings) for wear or damage. Replace any worn or damaged parts with original Rexroth spare parts.
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Reassemble the pump according to the installation instructions, ensuring the assembly accuracy and tightness.
6.3 Notes for Maintenance
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Before maintenance, stop the pump and cut off the power supply. Release the pressure in the hydraulic system to avoid oil spraying and personal injury.
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Use only original Rexroth spare parts and recommended hydraulic fluids to ensure the pump’s performance and service life.
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After maintenance, conduct a commissioning test again before putting the pump into operation.
7. Troubleshooting
The following table lists common faults, possible causes, and corresponding solutions. If the fault cannot be resolved, contact Bosch Rexroth technical support for assistance.
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Fault Phenomenon
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Possible Causes
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Solutions
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|---|---|---|
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No flow or insufficient flow
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1. Low oil level or air in the system; 2. Clogged suction filter or suction hose; 3. Swashplate angle is zero or too small; 4. Worn or damaged internal components; 5. Incorrect motor rotation direction
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1. Add hydraulic fluid and bleed air; 2. Clean or replace the suction filter and hose; 3. Adjust the swashplate angle; 4. Inspect and replace worn parts; 5. Correct the motor rotation direction
|
|
Abnormal noise
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1. Air in the system; 2. Insufficient oil supply; 3. Worn bearings or internal components; 4. Misalignment of drive shaft; 5. Clogged oil filter
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1. Bleed air; 2. Check oil level and suction system; 3. Replace worn bearings or components; 4. Adjust coaxiality; 5. Clean or replace the oil filter
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|
Oil leakage
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1. Damaged or aged seals; 2. Loose connections; 3. Excessive system pressure; 4. Cracked pump body
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1. Replace seals; 2. Tighten connections; 3. Check and adjust system pressure; 4. Replace the pump body
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|
Overheating of the pump
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1. Insufficient oil level or poor oil quality; 2. Clogged oil cooler; 3. Excessive system pressure; 4. Friction between internal components
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1. Add or replace hydraulic fluid; 2. Clean the oil cooler; 3. Adjust system pressure; 4. Inspect and repair internal components
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8. Related Documents
For more detailed information about the A4VSO series pump, refer to the following Rexroth documents:
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Technical Data Sheet RE 92050: Permissible technical data for A4VSO series 1, 2, and 3 axial piston variable pumps
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Technical Data Sheet RE 92053: Technical data for A4VSO pumps operating with HFC hydraulic fluids
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Technical Data Sheet RE 90220: Requirements for mineral oil-based hydraulic fluids for Rexroth axial piston units
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Data Sheets for Control Devices: RE 92060 (DR, DP, FR, DFR), RE 92064 (LR2, LR3), RE 92072 (MA, EM), RE 92076 (HM, HS, EO), RE 92080 (HD), RE 92088 (DFE1)
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Order Confirmation: Contains preset technical data of the purchased pump
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Installation Drawing: Contains outer dimensions, all connections, and hydraulic schematic of the pump
9. Contact Information
For technical support, spare parts purchase, or other inquiries, please contact Bosch Rexroth customer service or your local Rexroth distributor. You can also visit the official Bosch Rexroth website for more information.
