A4VG Series Piston Pump
The A4VG series piston pump is a swashplate-type axial piston variable displacement pump, primarily designed for closed-loop hydrostatic transmission systems. Below is a detailed introduction:
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I. Working Principle and Structural Features
• Swashplate Design: Achieves stepless flow adjustment by varying the swashplate angle, with flow proportional to drive speed and displacement.
• Modular Construction: Utilizes standardized components for easy maintenance and functional expansion, supporting multiple control modes (e.g., constant pressure, constant power, pressure cut-off).
• Bidirectional Hydraulic Transmission: Enables smooth reversal of fluid flow when the swashplate swings past the neutral position, suitable for forward/reverse operations.
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II. Core Performance Parameters
【表格】
Parameter Category Technical Specifications
Displacement Range Covers 28 cm³/rev to 1000 cm³/rev. Common models include A4VG28, A4VG56, A4VG125, A4VG250, etc.
Rated Pressure Continuous operating pressure up to 280 bar; peak pressure up to 350 bar (transient).
Speed Range Rated speed: 950–5,600 rpm; maximum speed limited to 8,000 rpm.
Control Modes Supports mechanical/hydraulic/electro-hydraulic proportional control with fast response and high precision.
Weight Range Varies by displacement: from 29 kg (A4VG28) to 156 kg (A4VG250).
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III. Functional Configurations
• Dual Protection Mechanism: Equipped with two relief valves on the high-pressure side for overload protection and charge pump functionality, preventing excessive system pressure.
• Integrated Auxiliary Systems: Built-in charge pump and control pump ensure fluid circulation and rapid system response in closed-loop systems.
• Pressure Cut-Off Function: Standard pressure cut-off valve reduces displacement automatically when system pressure reaches the set value, protecting components.
• Multi-Port Design: Includes test ports, charge ports, and other interfaces for real-time monitoring of pressure, flow, and temperature.
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IV. Typical Applications
• Construction Machinery: Driving systems for concrete pump trucks, excavators, loaders, and road rollers.
• Industrial Vehicles: Transmission systems for heavy-duty hydraulic platform trucks and mining dump trucks.
• Marine Equipment: Hydraulic power units for deck machinery, steering gears, and anchor winches on ships.
• Energy Sector: Yaw/pitch systems for wind turbines and hydraulic power stations for oil drilling rigs.
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V. Technical Advantages
• Energy Efficiency: Variable displacement ensures precise matching of pump output power with load demands, reducing energy waste.
• Long Service Life: Key components made of high-strength cast iron, coupled with optimized lubrication systems, extend operational lifespan.
• Environmental Adaptability: Optional low-temperature startup kits and high-temperature protection modules for operation in -40°C to +60°C environments.
• Maintenance Convenience: Modular design allows quick replacement of faulty components, minimizing downtime.
