Rexroth A11VO260 open-circuit variable hydraulic pump

The A11VO260 is a swashplate-type variable-displacement axial piston pump built by Bosch Rexroth for open-circuit hydrostatic drive systems. The "260" in the name refers to its geometric displacement — 260 cm³ per revolution — placing it at the large-displacement end of the A11VO family, which spans from 40 cc/rev up to 260 cc/rev.

How the A11VO260 Works

The Swashplate Principle

Inside the pump housing sits a cylinder block with a set of pistons arranged in a circular pattern around the drive shaft. As the shaft rotates, each piston rides against an angled swashplate. That angle forces the pistons to stroke in and out of their bores — pulling fluid in on the intake stroke and pushing it out on the discharge stroke.

The genius of this design is simple: change the angle of the swashplate, and you change how far each piston strokes. Steeper angle, more displacement per revolution, more flow. Flatten the swashplate toward zero degrees, and displacement drops toward zero — even with the shaft still turning at full speed. That's how the pump achieves infinitely variable flow between qV max and qV min = 0 without ever stopping the prime mover.

Open-Circuit Operation

In an open-circuit configuration, the pump draws fluid from a vented reservoir and sends it out to actuators (cylinders, motors), with return flow going back to the same tank. This is different from closed-circuit pumps (like the Rexroth A4VG or A11VLO variants used in hydrostatic transmissions), where fluid recirculates directly between pump and motor.

Open-circuit design makes the A11VO260 well suited to systems with multiple, independently switched actuators — think boom functions on a crane, or the various circuits on a concrete pump truck — where flow needs to be routed and interrupted by directional valves rather than continuously cycled between a single pump-motor pair.

Self-Priming and Charge Options

The pump is self-priming under normal conditions and can also run with tank pressurization or an optional built-in charge pump (impeller-type, found on the A11VLO variant) for applications needing more reliable inlet conditions at high speed or with long suction lines.

Control Options: Matching Flow to the Job

This is where the A11VO260 earns its reputation. Bosch Rexroth offers a genuinely broad menu of displacement controls, and picking the right one is arguably more important than the pump's raw specs.

Power Control (LR)

Power control (often designated LR) regulates displacement so that a set drive power is never exceeded at a constant input speed, following a hyperbolic pB × Vg = constant characteristic. As operating pressure climbs, the pump automatically swivels back toward minimum displacement to protect the prime mover from being overloaded. It's the classic choice for diesel-driven mobile equipment where you can't afford to stall the engine under load.

Load-Sensing Control (LS)

Load-sensing control adjusts displacement to match the actual flow demand of the connected valve/actuator, holding a fixed pressure margin (typically a differential setting between 14 and 25 bar, with 18 bar as a common standard) above the highest load pressure in the system. This minimizes throttling losses and heat generation — a big deal in duty cycles with fluctuating loads, like excavator or crane work.

Electric and Hydraulic Stroke Limiters (LRU, LRH)

Stroke limiters cap the maximum swivel angle either electrically (proportional solenoid current) or hydraulically (pilot pressure), letting an operator or a machine controller set a hard ceiling on flow output. A minimum control pressure — around 30 bar — is generally required to move the pump off its Vg max starting position.

Combination and Remote Controls

Many real-world installations stack controls together — for example, load-sensing with a power-limiting override, or electric proportional control layered with a pressure cutoff. Rexroth's catalog literature documents these combinations extensively because large mobile machines (cranes, drill rigs, concrete pumps) often need several protective and performance behaviors running simultaneously.

Maintenance and Troubleshooting Notes

Field technicians dealing with an A11VO260 typically focus on a few recurring wear points:

Piston and cylinder block wear — the most common source of gradually declining volumetric efficiency and internal leakage.

Valve plate condition — scoring or wear here directly affects pump efficiency and can produce audible noise changes.

Servo/control piston and regulator function — since the entire variable-displacement behavior depends on the control valve regulator responding correctly, a sluggish or drifting swashplate response is often a regulator issue rather than a pump-body issue.

Seal and port integrity — checked under actual operating pressure, not just static inspection, since dynamic seal leakage often only shows up under load.

Bias spring and cradle bearing condition — these return the servo piston and support the swashplate's rocking motion; wear here shows up as inconsistent displacement control.

For more information on the A11VO260 hydraulic pump, please visit https://www.baolilaihydraulic.com/.

Specifications

Selection Table

Q1: What control types are available for this pump?

A1: Common options include power control (LR), load-sensing control (LS), electric proportional stroke limiters (LRU), hydraulic stroke limiters (LRH), and various combination controls. The right choice depends on whether the priority is protecting the prime mover, minimizing energy loss, or giving precise operator/electronic command over flow.

Q2: What industries commonly use this pump?

A2: Concrete pumping equipment, cranes, drilling rigs, large excavators and loaders, and heavy stationary hydraulic power units are the most common applications given the pump's displacement class and pressure rating.

Q3: How to purchase an A11VO260 hydraulic pump?

A3: You can visit https://www.baolilaihydraulic.com/contact/ to contact us and purchase our products through various methods.

Q4: What is the price and delivery time of the A11VO260 hydraulic pump?

A4: The specific price and delivery time will be provided based on the specific model you provide.