0510325026 AZPF-11-005RAB01MB German Rexroth manufactures gear pumps

Frequently Asked Questions (FAQ)

1. Basic Parameters & Selection

Q: What is the displacement and pressure rating of this pump?

A: The geometric displacement is 5.6 cm³/rev. It has a maximum continuous working pressure of 250 bar, an intermittent pressure of 280 bar, and a peak pressure of 300 bar.

Q: What type of shaft and port connection does this model have?

A: This model (RAB) features a straight cylindrical shaft (Ø18 mm) with a keyway. The port connection is Pipe Thread (ISO 228-1 / BSP), which is different from the metric threaded or flanged ports found in other AZPF models.

Q: What is the rotation direction?

A: Clockwise rotation when viewed from the shaft end.

2. Installation & Commissioning

Q: What are the critical installation requirements?

A:

• Shaft Alignment:​ Use a flexible coupling. Radial runout should be < 0.1 mm, angular error < 1 degree. Rigid connections cause bearing failure.

• Suction Conditions:​ Inlet absolute pressure must be ≥ 0.7 bar​ to prevent cavitation. For this small displacement pump, ensure the suction line is short and direct.

• Priming:​ Never run the pump dry.​ Fill the housing with clean oil before the first start.

Q: How should the case drain port be connected?

A: The drain line must connect directly to the tank​ (no valves/filters), below the fluid level but above the pump centerline. Backpressure must not exceed 1 bar.

3. Operation & Troubleshooting

Q: The pump is very noisy. What is the cause?

A: Noise is usually cavitation​ (whining) or aeration​ (crackling).

• Cavitation:​ Check for clogged inlet filters, high oil viscosity, or low oil level.

• Aeration:​ Check for air leaks in the suction line.

• Mechanical Noise:​ Check for shaft misalignment or worn bearings.

Q: How do I calculate the actual flow output?

A: Theoretical flow = 5.6 (cm³/rev) × Speed (rpm) / 1000. Actual flow will be 5-10% lower​ due to internal leakage. A drop of more than 15% indicates significant wear.

Q: The pressure does not reach the rated value. What is wrong?

A: Common causes include:

1. Internal Wear:​ Increased clearance between gears and side plates.

2. System Leakage:​ Check relief valves and actuators.

3. Low Motor Speed​ or incorrect system settings.

4. Maintenance

Q: What type of oil and cleanliness are required?

A: Use ISO VG 32/46/68 mineral-based oils (HL, HLP). The oil cleanliness must be NAS Class 9 or cleaner​ (ISO 4406 18/16/13) for long bearing life.

Q: Can I repair this pump myself?

A: Not recommended for critical applications.​ While seals can be replaced, rebuilding the precision sliding bearings and pressure-compensated side plates requires special tools and testing. An exchange unit is often safer.

Q: What is the expected service life?

A: Under correct conditions (clean oil, proper viscosity, rated load), the B10 life can reach several thousand hours. Oil contamination is the primary cause of premature failure.

Disclaimer:​ This data is based on standard Rexroth AZPF series documentation. Always refer to the official datasheet (RE 10 250) for your specific application and safety guidelines.