描述

A4V40 A4VG71 A4VG28DA A4VG90 A4VG180 A4VG125 A4VG250 Axial Piston Pump Variable Pump for Bosch Rexroth

Displacement, Pressure, and Performance Range

The Rexroth A4V and A4VG platform covers seven distinct displacements: A4V40, A4VG28DA, A4VG71, A4VG90, A4VG125, A4VG180, and A4VG250. Each model is tailored for a specific power band – from the compact 40 cc/rev unit up to the high‑output 250 cc/rev version – yet all share the same rugged design philosophy. These pumps are built to handle continuous working pressures up to 350 bar (≈5,075 psi) and can endure higher transient spikes without compromising integrity. This pressure headroom provides a vital safety buffer during shock‑loaded cycles, directly enhancing machine uptime and lowering long‑term maintenance costs across the entire range.

Swashplate Principle: The Heart of a Variable Displacement Pump

The exceptional performance of every pump in this series – whether the A4V40, the A4VG28DA, or the large‑capacity A4VG250 – stems from the same axial‑piston, variable‑angle swashplate concept that defines Rexroth’s hydraulic expertise.

• Fundamental Mechanical Action – Several pistons are mounted in a circular array around a rotating cylinder block. These pistons bear against an angled swashplate. As the drive shaft turns, the inclined surface forces each piston to move in and out of its bore, generating the pumping stroke.

• Key to Efficiency – The swashplate angle is not fixed; it can be altered on the fly. Changing this tilt modifies the piston stroke length, which directly varies the pump’s displacement and flow output – from zero to maximum – while the input speed stays constant. This on‑demand flow control is the core technology that eliminates wasteful throttling, cuts heat generation, and delivers substantial energy savings in real‑world operation.

Intelligent Control: Pump Perfectly Matched to Application

The true flexibility of the A4V and A4VG family comes from its versatile control options. The pump provides the muscle, while the chosen control system acts as the brain, fine‑tuning performance to match specific job requirements – a feature available on every model, from the A4VG71 to the A4VG180.

• HD (Hydrostatic) Control – A pressure‑compensated hydraulic control that automatically reduces displacement when system pressure nears a preset limit, effectively acting as an integrated pressure‑relief function. This robust, simple solution is ideal for drive systems where durability and overload protection are paramount.

• EP (Electro‑Proportional) Control – This system translates electrical commands (e.g., 0‑10 V or 4‑20 mA signals) into proportional swashplate movement via a solenoid valve. It enables smooth, stepless flow regulation through a joystick or PLC, offering intuitive and precise machine control.

• EW (Electro‑Proportional Load Sensing) Control – Combining proportional flow control with load‑sensing (LS) logic, this option delivers the highest efficiency. The pump supplies exactly the flow the actuator demands, maintaining a fixed pressure margin above the load. This on‑demand matching drastically reduces energy waste, cooling needs, and operating costs – especially on complex, multi‑function machines.

All these control strategies are fully compatible with the entire model lineup – from the A4V40 up to the A4VG250 – ensuring that you get the right combination of power, precision, and economy for your application.

FAQ 

Q1: What is the primary application difference between the A4VG28 and a fixed-displacement pump?

A1:The A4VG28 is a variable-displacementpump. It is the core component for closed-loop, hydrostatic drive systems (e.g., for travel drives) or sophisticated open-loop work hydraulics requiring variable flow. A fixed-displacement pump provides constant flow, which must then be throttled or bypassed, often wasting energy. The A4VG28 adjusts its output to match demand, saving energy and reducing heat.

Q2:What is the most critical maintenance aspect for ensuring long service life?

A2: Beyond adhering to recommended oil change intervals, filtration is paramount.​ Maintaining fluid cleanliness to ISO 4406 19/17/14 or better (NAS 1638 Class 8) is non-negotiable. The pump’s high-precision components, with tight tolerances, are highly susceptible to wear from particulate contamination. Investing in a high-quality filtration system protects your investment in the pump.

Q3:How to purchase an A4VG28 hydraulic pump?

A3:You can click on the right sidebar or the contact information in the top bar to contact us to purchase. You can do so via email, form, WeChat, WhatsApp, or other methods.

Q4:What is the price and delivery time of the A4VG28 hydraulic pump?

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