Bosch Rexroth AA4VSO180 Open Circuit Hydraulic oil Pump

The AA4VSO series is Rexroth's answer to medium-to-large open circuit requirements. The “180” in the model name refers to its nominal displacement of 180 cm³/rev—a sweet spot for applications needing substantial flow without jumping to a massive frame size.

This pump operates on the swashplate principle: rotating pistons compress against an angled plate, converting mechanical torque into hydraulic flow. Designed primarily for industrial hydraulics and off-highway equipment, it handles pressures up to 350 bar (5,076 psi) continuously, with peak pressures hitting 400 bar.

Technical Specifications That Matter

Don't just scan the datasheet. Focus on these critical parameters:

Displacement: 180 cm³/rev (variable, typically 0–100%)

Operating Pressure: Rated 350 bar, max 400 bar

Speed range: 400 to 1800 rpm (depending on inlet condition)

Flow direction: Suction and pressure sides standard (bidirectional optional)

Mounting: SAE flanges (2-hole or 4-hole options)

Porting: Metric or inch thread, SAE split-flange compatible

Control Systems-Tailoring Flow to the Task

The pump's versatility comes from its modular control system. You choose the regulator, and the pump adapts. Here are the most common ones:

DR-Pressure Control

Maintains constant outlet pressure regardless of flow demand. Ideal for presses and injection molding machines.

DFR-Load Sensing (LS)

Adjusts displacement to maintain a fixed pressure differential (typically 14–20 bar) across a directional valve. This saves energy—only pumps the flow the actuator needs. Widely used in mobile excavators and drill rigs.

LR-Torque Control (Power Limiting)

Limits input torque to protect a diesel engine or electric motor from overloading. Two variants: constant power (LR) or electronic droop.

Common Failure Points

From field data, the AA4VSO180 is robust—but not invincible. Watch for these issues:

1.Inlet starvation-The 180 cm³/rev demands a well-sized intake line (min 2 meters head or 0.8 bar absolute pressure at port). Use a vacuum gauge.

2.Contamination sensitivity-Maintain ISO 4406 cleanliness class 18/15/12 (NAS 7). A failed servo piston filter often precedes pump failure.

3.Case drain backpressure-Keep below 2 bar absolute, or the shaft seal will weep.

Pro tip: If you see brass particles in the case drain filter, the slipper pads are lifting off the swashplate—usually from pressure spikes or low oil viscosity.

Application Examples

Hydraulic Press Brake (150-ton capacity): Two AA4VSO180 pumps in parallel, DFR load-sensing control, running at 180 bar. Result: fast approach, precise bending, and <5% energy waste compared to fixed gear pumps.

Ship Deck Crane (10-ton SWL): Single AA4VSO180 with EP electronic control, coupled to a 90 kW electric motor. Open circuit allows easy integration of a bypass filter and cooler.

Scrap Shear (500-ton force): The pump operates in torque-limiting mode (LR) during cutting peaks, preventing a 250 HP diesel engine from lugging.

Installation & Maintenance Best Practices

1.Mounting: SAE J744 flanges. Torque bolts to spec—uneven loading warps the housing.

2.Shaft coupling: Use a flexible coupling with 2–3° angular misalignment max. No axial load on the pump shaft.

3.Startup: Fill the case drain port before first rotation. Run at no load for 30 seconds.

4.Oil: HVLP 46 or 68 (ISO VG 46/68). Keep viscosity between 16–100 mm²/s at operating temp.

For more information on the AA4VSO180 hydraulic pump, please visit https://www.baolilaihydraulic.com/product/.

Specifications

Selection Table

Q1:What’s the difference between AA4VSO180 and A4VSO180?

A1:The second “A” indicates an industrial version with metric ports and ISO mounting. The single-A version typically has SAE ports. Internals are identical.

Q2: My pump is noisy at high rpm. Causes?

A2:Most likely inlet restriction. Check suction strainer, hose collapse, or oil viscosity. Also inspect the compensation control—hunting can create a “whining” resonance.

Q3:What is the price and delivery time of the AA4VSO180 hydraulic pump?

A3:The specific price and delivery time will be provided based on the specific model you provide.

Q4:How to purchase an AA4VSO180 hydraulic pump?

A4:You can visit https://www.baolilaihydraulic.com/contact/ to contact us and purchase our products through various methods.