Rexroth A4VG Series 125cc Axial Piston Variable Hydraulic Pump for Closed Circuit Mobile Machinery

A4VG125EP4D1/32R-NZF02F011SP Rexroth A4VG125 Closed Circuit Hydraulic Axial Piston Pump

Key Features

1. High pressure rating: nominal pressure 400 bar, peak pressure up to 450 bar, stable under heavy load working condition

2. EP4 electronic control, fast response, stepless flow adjustment, easy remote control

3. Integrated charge pump & pressure protection valve, compact structure, less piping work

4. Smooth reversing flow when passing neutral position, low vibration & low noise

5. Hardened internal components, excellent wear resistance, long service life

6. Modular design, easy maintenance and spare parts replacement

Technical Parameters

Specifications:

Application Scenarios

· Asphalt paver

· Road roller

· Crawler carrier

· Mobile drilling rig

· Small & medium crawler excavator

· Other heavy mobile closed-loop hydrostatic drive equipment

Competitive Advantage:

1. Equipped with EP electric proportional variable mechanism, it accurately adjusts pump displacement through electric signals with sensitive flow response. It is easy to connect to the whole machine electronic control system, suitable for automatic operation of mobile drilling rigs. It can match output power in real time when load changes and delivers stable control performance.
2. This 125cc closed-circuit variable piston pump features compact structure and powerful power output under high pressure, with excellent resistance to alternating impact. It occupies little installation space and is suitable for mobile hydraulic systems with limited space such as mobile drilling rigs and small construction machinery.
3. English: The core friction pairs are made of high-strength wear-resistant materials, which can withstand harsh environments such as dust and temperature fluctuations at field construction sites and work stably continuously. Original and replacement spare parts are in sufficient supply, easy to disassemble and repair, shortening the downtime of drilling rigs.

The Analysis For Rexroth A4VG125 Piston Pump Common Breakdown:

1. Insufficient output flow and reduced drilling speed of the drilling rig. Wear between pistons and cylinder block or scratches on valve plate will increase internal leakage, making the pump fail to reach rated flow. It directly causes weak rotation and feed movement of mobile drilling rig and lower drilling efficiency. The lack of power is more obvious when working in hard rock strata.
2. Abnormal noise and excessive vibration of pump body. The main causes are contaminated hydraulic oil, air entering suction pipeline and bearing wear. Oil impurities and cavitation continuously erode precision internal parts. Vibration and noise gradually worsen. Long-time operation will damage internal pump components, and pump core seizure may shut down the drilling rig in severe cases.
3. EP electric proportional control failure and unadjustable displacement. Damaged proportional electromagnet, stuck control spool or poor circuit contact prevent the EP variable mechanism from receiving electronic control signals. Pump displacement is fixed and unadjustable. The drilling rig power cannot be adjusted according to formation conditions, resulting in unstable pressure and abnormal energy consumption and affecting drilling accuracy.