Bosch Rexroth A10VO88 A10VSO88 swashplate variable hydraulic pump

The A10VO88 and A10VSO88 are variable-displacement axial piston pumps built on a swashplate design, manufactured by Bosch Rexroth for open-circuit hydraulic systems. The "88" refers to the geometric displacement size (NG 88) — roughly 88 cm³ per revolution at maximum swashplate angle.

How a Swashplate Variable Pump Works

The Basic Piston-and-Swashplate Principle

Inside the housing, a cylinder block containing several pistons rotates around a central shaft. Each piston's shoe rides against a swashplate set at an angle relative to the rotating axis. As the block spins, that angle forces each piston in and out of its bore — pulling fluid in on one half of the rotation, pushing it out under pressure on the other.

Why "Variable" Matters

Unlike fixed-displacement pumps, the A10VO88/A10VSO88 can change the swashplate angle while running. Tilt the plate further and stroke length — and flow — increases. Bring it toward perpendicular and flow drops toward zero. One pump can then serve multiple duty cycles instead of running at full output constantly, which is why these pumps show up so often in energy-conscious hydraulic circuits.

Control Options That Shape Real-World Performance

The swashplate angle is managed by a control device mounted on the pump — this is where the family gets genuinely flexible:

DR (pressure control) – holds system pressure constant, reducing flow as pressure nears the set point.

DFR (pressure and flow control) – combines pressure cutoff with a secondary flow limiter.

DFLR / LR3 (load-sensing control) – matches output to actual downstream demand for better efficiency.

EO / EP (electric proportional control) – lets a controller vary displacement electronically.

Choosing the right control type is arguably the single most consequential spec decision, since it determines behavior under load, not just maximum output.

Real-World Applications

Mobile Equipment

On excavators, wheel loaders, and telehandlers, the A10VO88 typically drives boom, arm, and bucket circuits where load demand swings constantly. Load-sensing variants let the engine avoid wasting horsepower on fluid that isn't needed at a given moment — a direct fuel-economy win.

Stationary Industrial Machinery

The A10VSO88 is a familiar sight in hydraulic power units for injection molding machines, presses, and machine tools, where precise pressure control matters more than mobility.

Combination and Tandem Pump Setups

Both variants support tandem configurations — a second pump mounted on the first's through-drive — common where a machine needs two independent circuits (e.g., a high-pressure work circuit and a lower-pressure steering circuit) without a separate gearbox.

Installation and Maintenance Considerations

Mounting Orientation and Fluid Level

These pumps are typically designed to run fully submerged in the reservoir. If the pump sits above the minimum fluid level in the installation drawing, a case-drain priming or check-valve arrangement becomes necessary to prevent dry-running on startup — a leading cause of early bearing and shoe-plate wear.

Fluid Selection

Standard versions run on HLP mineral oil per DIN 51524. Fire-resistant fluid versions require different seals and, in some cases, derated pressure limits — don't assume a standard-fluid pump can be switched to fire-resistant fluid without checking the ordering code.

Common Wear Points

Swashplate bearing and control piston seals – sluggish or erratic displacement response

Piston shoes and slipper pads – scoring, usually traced to contamination or cavitation

Shaft seal – frequent source of external leaks after thermal cycling

Control valve spool (DR/DFR variants) – sticking causes pressure control to hunt or overshoot

Torque and Alignment

Shaft misalignment is one of the fastest ways to shorten bearing life. Following Bosch Rexroth's specified coupling tolerances and mounting-bolt torque values matters for rated service life.

For more information on the A10VO88/A10VSO88 hydraulic pump, please visit https://www.baolilaihydraulic.com/.

Specifications

Selection Table

Q1: What causes a variable pump to lose pressure control?

A1: Most commonly: a worn or contaminated control valve spool, a failing pressure-control cartridge, suction-side air ingress, or worn swashplate bearings — contamination is the most frequent root cause.

Q2: How do I identify the exact specs of a pump I already have?

A2: The type-code nameplate on the housing decodes size, control type, shaft type, rotation, and seal material — cross-reference it against the relevant RE data sheet (e.g., RE 92701 for A10VO Series 31, RE 92711 for A10VSO Series 31).

Q3: How to purchase an A10VO88/A10VSO88 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 A10VO88/A10VSO88 hydraulic pump?

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