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A11VO for excavator

The A11VO is a high-pressure variable-displacement piston pump designed by Rexroth specifically for open-loop excavator systems. It features load-sensing, constant-power, and pressure-cut-off capabilities and is widely used in excavators ranging from 6 to 50 tons.

First, Models and Displacement (Mainstream Excavator Models)

1. A11VO: Base model (self-priming)

2. A11VLO: With built-in makeup pump (more stable at high displacement/high speed)

3. Common specifications (cm³/r):

95: 6–10-ton compact excavators

130/145: 12–20-ton medium excavators

190/260: 25–50-ton large excavators

Second, Core Parameters (Excavator Operating Conditions)

1. Rated Pressure: 350 bar; Peak: 400 bar

2. Maximum Speed:

95/130/145: 2500 rpm

190/260: 2300 rpm

3. Control Mode (Excavator Standard): LRDS (Load Sensing LS + Constant Power LR + Pressure Cut-off DR)

4. Drive: 100% through-shaft, compatible with series-connected pilot pumps/gear pumps

Third, How the A11VO Operates in Excavators

1. Core: Swashplate-type variable displacement; the swashplate angle determines displacement (0–100% stepless).

2. Three Major Control Systems Working in Concert (LRDS):

Load Sensing (LS): Pump pressure automatically matches load pressure, delivering oil on demand for energy efficiency.

Constant Power (LR): P × Q ≈ constant, preventing engine stalling and shutdown.

Pressure Cut-off (DR): Automatically reduces displacement at ultra-high pressures (e.g., 380 bar) to protect the system.

3. A11VLO Make-up Pump: Forced suction prevents cavitation and ensures stable suction at high speeds and high flow rates.

Fourth, Exclusive Advantages for A11VO Excavators

1. High-Pressure and High-Efficiency: Rated for 350 bar, with volumetric efficiency ≥94% for fuel savings.

2. Energy-Efficient and Fuel-Saving: LS+LR composite control reduces fuel consumption by 15–30% compared to older models.

3. Fast Response and Smooth Operation: Variable response <100 ms; coordinated composite movements (boom + swing + travel).

4. Through-Shaft Integration: Directly connects to the pilot pump in series, saving space and reducing costs.

5. High Reliability: Three major friction pairs (plunger/cylinder block, slipper/swash plate, distribution plate) feature high precision and wear-resistant coatings, suitable for harsh job site conditions.