The Rexroth A8V55 is a axial piston pump renowned for its reliability and efficiency in various industrial applications. Manufactured by Bosch Rexroth, this pump is designed to meet the demanding requirements of modern hydraulic systems.
Technical Specifications:
Type: Axial piston variable double pump with a bent-axis design.
Displacement: 55 cm³/rev per pump; total displacement of 110 cm³/rev.
Pressure:
- Rated Pressure: 315 bar
- Peak Pressure: 400 bar
Speed Range: 500 to 3000 RPM.
Control Mechanism: Typically features a combined HP total power constant control; can also have separate constant power control for each pump.
Flow Characteristics: Flow is proportional to speed and displacement, with infinitely variable adjustment between 25° and 7° tilt angles.
Structural Features: Spherical distribution between the rotor and distribution plate allows for automatic alignment during operation, resulting in lower circumferential speed and higher efficiency.
Applications: Suitable for various industrial environments, including oil fields, construction sites, and manufacturing facilities.
Brand and Quality: As a Bosch Rexroth product, the A8V55 is trusted for its high pressure tolerance, efficiency, high power transmission, wide speed range, and long service life.
Common Issues and Maintenance:
Regular maintenance is crucial to ensure the optimal performance and longevity of the A8V55 pump. Common issues include:
Inability to Prime or Lack of Pressure:
- Mismatch between the drive motor and pump rotation direction.
- Dislodged pump transmission key.
- Reversed inlet and outlet connections.
- Low oil levels in the reservoir.
- Insufficient drive motor speed.
- High oil viscosity.
- Low oil temperature leading to high viscosity.
- Blocked suction lines or filters.
- High filtration precision of suction filters causing flow restrictions.
- Air leaks in the suction line.
Insufficient Flow:
- Inadequate speed.
- Hydraulic system leaks.
- Loose pump cover bolts.
- Leaks in the suction line.
- Insufficient suction.
Pressure Issues:
- Unprimed pump or insufficient flow.
- Low or failed pressure setting of the relief valve.
- System leaks.
- Loose pump cover bolts.
- Air leaks in the suction line.
- Insufficient suction.
Excessive Noise:
- Air leaks in the suction line.
- Insufficient suction.
- Misalignment between pump shaft and drive motor.
- Presence of air bubbles in the oil.
- Excessive pump speed.
- High pump pressure.
- Air leaks in shaft seals.
Overheating:
- High oil temperature.
- Low oil viscosity leading to excessive leakage.
- Operating at high pressures.
- Direct connection of return line to pump inlet.
Pump Overheating:
- Mechanical or fluid friction generating heat.
Oil Leaks:
- Damaged shaft seals or defects on the shaft.
- Excessive internal leakage increasing pressure at the seal.
- Overly narrow or long drain lines.
- Loose external oil lines or damaged fittings.
- Loose bolts on the variable adjustment mechanism, leading to seal damage.
- Casting defects or poor welding in the pump housing.
To address these issues, it's essential to:
- Shut Down Power and Relieve Pressure: Before maintenance, disconnect the power supply and relieve hydraulic pressure.
- Disassemble and Clean: Use appropriate tools to separate the pump from the inlet and outlet lines. Clean all components thoroughly with suitable cleaning agents.
- Inspect and Replace Seals: Check all seals for wear or damage and replace as necessary.
- Examine Components: Look for cracks, deformation, or excessive wear on other parts. Replace any faulty components.
- Use Appropriate Hydraulic Fluid: Select the correct hydraulic fluid and change it regularly to maintain cleanliness and system efficiency.
- Prevent Contamination: Ensure cleanliness during maintenance to prevent foreign particles from entering the system.
- Clean Hydraulic Reservoir: Periodically clean the reservoir to prevent oil degradation.
- Avoid Air and Water Contamination: Prevent air and water from entering the pump to avoid corrosion and oil degradation.
- Maintain Optimal Oil Temperature: Ensure the oil temperature remains within the recommended range for optimal pump operation.
- Regular Maintenance: Perform routine inspections and maintenance to ensure all components function correctly.
- Safety and Cleanliness: Maintain safety and cleanliness during diagnostics and repairs.
By adhering to these maintenance practices, you can ensure the reliable operation and extended service life of the Rexroth A8V55 pump.
