Rexroth A11VO95 open-circuit axial piston hydraulic pump

The A11VO95 is a swashplate-type axial piston pump designed for open-circuit hydraulic systems. Unlike closed-circuit pumps (like the A4VG or A6VM series, which recirculate fluid directly between pump and motor), open-circuit pumps draw fluid from a reservoir/tank and return it to that same tank after the actuator has done its work. This makes the A11VO95 a natural fit for:

Construction and earthmoving equipment (excavators, wheel loaders, cranes)

Industrial power units and machine tools

Injection molding and plastics processing machinery

Marine and offshore hydraulic systems

Agricultural machinery

How the A11VO95 Works

Understanding the operating principle helps when troubleshooting or specifying a replacement unit.

The Displacement Mechanism

As the cylinder block rotates (driven by an engine or electric motor via the input shaft), each piston is forced in and out of its bore by the angled swashplate. On the intake stroke, the piston bore's volume increases, pulling fluid in from the suction port. On the discharge stroke, the piston pushes fluid out through the discharge port at system pressure. Because all nine (typically) pistons fire in sequence, the pump produces a continuous, if slightly pulsed, flow output.

Changing the swashplate angle — from near-zero to maximum — changes how far each piston travels, which changes displacement per revolution and therefore output flow, independent of pump shaft speed.

Control Options in Practice

This is where the A11VO95 gets interesting for system designers, because Rexroth offers it with several distinct control types:

DR (pressure control) — the pump automatically reduces displacement as system pressure approaches a set maximum, protecting the system and controlling power without a separate relief valve doing all the work

LR (load-sensing control) — the pump matches output flow to actual load demand, sensing pressure drop across a downstream valve; this is the standard for excavators and other multi-function machines because it minimizes wasted energy and heat

DRE / EP (electric proportional control) — flow is commanded electronically, which suits machines with electrohydraulic control architectures

NR (constant power / horsecontrol) — limits displacement based on pressure to keep input power within the prime mover's capacity, protecting the diesel engine or electric motor from stalling under high load

Technical Specifications Overview

While exact values depend on the specific ordering code (control type, shaft configuration, rotation direction, etc.), the A11VO95's typical envelope includes:

Installation and Application Best Practices

Sizing for the System

Undersizing the A11VO95 relative to actual flow demand causes cavitation and premature wear; oversizing wastes input power and increases heat load. Engineers typically size the pump against the largest simultaneous flow demand in the duty cycle, then rely on the control type (especially load-sensing) to handle the rest of the operating envelope efficiently.

Fluid Cleanliness and Filtration

Axial piston pumps run tight tolerances between pistons and bores. Contaminated fluid is the single biggest driver of premature failure in this pump family. A target cleanliness of ISO 4406 18/16/13 or better is standard practice for A11VO-series pumps, and return-line and suction filtration should be sized and maintained accordingly.

Common Failure Modes

Swashplate bearing wear from prolonged operation at high angle under high pressure without adequate lubrication

Piston shoe scoring typically traced back to fluid contamination or cavitation

Control valve drift in DR/LR controls, often from clogged orifices in the control pilot circuit rather than the main pump itself

Shaft seal leakage after extended service life, especially in units exposed to thermal cycling

Maintenance Notes

Routine maintenance for the A11VO95 centers on fluid analysis, case drain flow monitoring (a rising case drain flow rate is often the earliest sign of internal wear), and periodic inspection of the control valve assembly. Because the pump is modular, control units and some wear components can often be serviced without a full pump teardown, which is a genuine advantage over older, less modular pump designs.

For more information on the A11VO95 hydraulic pump, please visit https://www.baolilaihydraulic.com/.

Specifications

Selection Table

Q1: Is the A11VO95 a fixed or variable displacement pump?

A1: Variable. Displacement changes via the swashplate angle, controlled by whichever control option (DR, LR, EP, etc.) is specified in the ordering code.

Q2: How do I know which control type I need?

A2: Load-sensing (LR) control suits multi-function mobile machines like excavators where flow demand varies rapidly. Pressure control (DR) suits applications like injection molding or presses where high force at low flow is common. Electric proportional (EP/DRE) suits machines with electrohydraulic control systems needing programmable flow response.

Q3: How to purchase an A11VO95 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 A11VO95 hydraulic pump?

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