A11VO260LG2DU2/11L-NZD12N00VH-S Rexroth Variable Pump 350Bar

Product Overview

The A11VO260LG2DU2/11L-NZD12N00VH-S is a Bosch Rexroth A11VO series 11 swashplate-type axial piston variable displacement pump, nominal size 260, with a geometric displacement of 260 cm³/rev, purpose-designed for hydrostatic drives in open-circuit hydraulic systems. The pump operates on the swashplate principle, with flow proportional to drive speed and displacement, infinitely variable through swashplate angle adjustment, at a nominal pressure of 350 bar and maximum pressure of 400 bar.

The full order code A11VO260LG2DU2/11L-NZD12N00VH-S decodes as follows: A11VO indicates the open-circuit swashplate variable pump series; 260 is the nominal displacement of 260 cm³/rev; LG2 specifies pilot-pressure-related power control (Positive Power Override) — an external pilot pressure signal overrides the power controller setting, enabling dynamic adjustment of pump output power based on auxiliary control signals; DU2 is the control variant code; 11 is the series designation; L indicates left-hand rotation (counterclockwise, viewed from shaft end); N specifies NBR nitrile rubber seals; Z specifies splined shaft; D12 specifies SAE 2-bolt mounting flange; N00 indicates no through-drive and standard port configuration; VH-S specifies special configuration codes.

Manufactured to exact Rexroth A11VO260 platform specifications, this pump delivers true drop-in interchangeability — identical mounting flange, shaft specification, port positions, and displacement rating. Every unit undergoes 100% simulated operating condition testing before shipment.

Technical Specifications

The following specifications are based on Bosch Rexroth A11VO series 11 official technical data (RE 92500) and publicly available product data:

• Model: A11VO260LG2DU2/11L-NZD12N00VH-S

• Manufacturer: Bosch Rexroth

• Series: A11VO series 11

• Design: Swashplate-type axial piston variable displacement pump, open-circuit

• Nominal Size: 260

• Geometric Displacement: 260 cm³/rev (15.87 in³/rev)

• Nominal Working Pressure: 350 bar (5100 psi)

• Peak Pressure: 400 bar (5800 psi)

• Maximum Speed (Vg max): 1800 rpm

• Maximum Speed (Vg ≤ Vg max): 2100 rpm (series reference)

• Theoretical Flow at 1800 rpm (Vg max): 468 L/min

• Maximum Power (Δp = 350 bar): Approx. 273 kW

• Maximum Torque (Vg max and Δp = 350 bar): Approx. 1449 N·m

• Rotation Direction: Left hand (counterclockwise, viewed from shaft end)

• Control Type: LG2 — Pilot-pressure-related power control (positive override), external pilot pressure signal overrides the power controller setting

• Mounting Flange: SAE 2-bolt flange (SAE J744)

• Shaft Specification: Splined shaft

• Seal Material: NBR nitrile rubber

• Through-Drive: No (N00)

• Weight (Reference): Approx. 125 kg

• Housing Material: Cast iron

• Operating Fluid: Mineral hydraulic oil (DIN 51524 HLP)

• System Type: Open-circuit hydraulic system

Key Technical Advantages

1. Precise Dynamic Adjustment via LG2 Pilot-Pressure-Related Power Control

The LG2 control is a positive power override variant of power control, adjusting the power controller through an external pilot pressure signal. Under pilot pressure, the control force assists the power controller’s adjustment spring, enabling dynamic adjustment of pump output power based on external control signals for real-time modification of the power setting. This control method is particularly suited to mobile machinery applications requiring dynamic matching of engine power under varying operating conditions, such as excavators and loaders with frequent load changes.

2. High Power Density and Efficiency from Swashplate Design

The A11VO260 employs a swashplate design in which pistons act on the swashplate through slippers, delivering approximately 273 kW output power at 260 cm³/rev displacement and 350 bar nominal pressure — a high power density. The cast iron housing provides excellent rigidity and damping characteristics, maintaining stable volumetric efficiency and low-noise operation across the full pressure range.

3. 100% Through-Drive Capability for Multi-Pump Systems

The A11VO series supports 100% through-drive capability, allowing same-size or smaller gear pumps and axial piston pumps to be connected in series at the rear of the pump for multi-pump common-shaft output. This extends hydraulic system flow output without increasing installation envelope, simplifying complex hydraulic system layout.

4. Compact Installation Envelope with Standardized Interfaces

The A11VO260 weighs approximately 125 kg, offering a compact installation envelope within the 260 cm³/rev displacement class. The SAE 2-bolt flange and splined shaft conform to SAE J744 standards, with mounting surface flatness requirements that are easily achievable and bolt tightening torques per the product manual ensuring sealing reliability.

5. 100% Simulated Operating Condition Testing

Every pump undergoes a comprehensive factory test protocol: continuous operation at 350 bar nominal pressure to verify volumetric and total efficiency, 400 bar peak pressure cycling to validate housing and seal integrity, and full-speed-range verification of displacement control linearity and LG2 control response. Test documentation is supplied with each unit.

Application Areas

• Large Excavators: Crawler excavator travel and swing hydraulic systems — LG2 control suits dynamic engine power matching requirements

• Wheel Loaders: Large loader implement and travel hydraulic drive systems

• Concrete Pump Trucks: Boom hydraulic systems and pumping circuit hydraulic drives

• Mining Equipment: Mine transport vehicles and underground LHD loader hydraulic drive systems

• Cranes: Large truck crane main hydraulic pumps and auxiliary hydraulic circuits

• Industrial Hydraulic Power Units: Large presses and forging equipment hydraulic power systems

Expert Maintenance Tips

1. LG2 Control Pilot Pressure Calibration and Verification

LG2 pilot-pressure-related power control relies on precise matching of the external pilot pressure signal. After pump or control module replacement, verify the pilot pressure-to-power setting relationship at rated speed and 50% displacement, confirming it falls within the factory calibration curve. Pilot signal line cleanliness should be maintained at NAS 8 or better — particulate contamination can cause control piston sticking or sluggish response. When adjusting power settings, first confirm that the system maximum pressure limit is already set to avoid incorrect adjustment sequence causing system overload.

2. Mandatory Case Pre-Fill and Air Purging

After installation, fill through the highest case port with clean hydraulic fluid filtered to ≤10 μm until oil overflows. Open the bleed plug and run the pump at idle until bubble-free oil flows continuously. Do not apply load until the system is confirmed air-free. Dry starting will cause catastrophic wear to the slipper and swashplate friction pair within seconds — and with larger displacement pumps, the larger slipper area accelerates dry-start damage.

3. Mounting Surface Flatness and Bolt Torque

The mounting surface must be flat and clean to prevent pump body deformation from uneven mounting surfaces, which can affect valve plate sealing. Bolt tightening torque for large-size pumps should follow Rexroth official technical manual specifications. Use a torque wrench with staged tightening and periodically verify fastener tightness.

4. Fluid Cleanliness and Viscosity Control

Maintain system cleanliness at NAS 9 or ISO 18/16/13 or better. Recommended operating viscosity is ISO VG 46 or VG 68, with an optimum range of 14–50 cSt. Install a 10 μm nominal filtration element in the suction line; replace after the first 200 hours, then inspect or replace every 500 hours. With the A11VO260’s large displacement and high system flow, filter clogging occurs relatively faster — strengthen filter differential pressure monitoring.

5. Precision Control for Through-Drive Series Applications

When using through-drive to connect a rear pump, strictly control rear pump weight and coaxial precision, and verify total torque and speed matching. Concentricity deviation should be within 0.05 mm, with angular deviation not exceeding 0.5°. Excessive rear pump weight can cause bearing load imbalance — add support beneath the pump body if necessary.