9101530 Hitachi EX120-2 Excavator Hydraulic Pump Assembly

This product is an original axial piston variable displacement pump, which uses a cast iron pump body and an internal core of a slant disc variable displacement mechanism. Typical technical parameters: displacement of approximately 91 cm ³/r, rated pressure of 34.3 MPa, maximum pressure of 39.2 MPa, rated speed of 2000 r/min. The pump body integrates a pressure compensator and a flow control valve, which can automatically adjust the output flow according to the load, achieving energy-saving and efficient operation. This pump complies with standards such as ISO 3019 and GB/T 2346, and adopts wear-resistant designs such as bimetallic distribution plates and hard alloy plungers. It can operate stably in oil temperature environments ranging from -25 ℃ to+90 ℃, with a volumetric efficiency of ≥ 92%.

This product is the HPV091DS axial piston variable displacement pump, which is the power core of the excavator hydraulic system. The pump body is made of sturdy cast iron material with a nominal flow rate of approximately 100 L/min. It can provide a stable high-pressure oil source for all movements of the entire machine, including the boom, arm, bucket, walking, and rotation. As a variable displacement pump, its core lies in the built-in inclined plate variable adjustment mechanism, which can automatically change the inclination angle of the inclined plate according to the driver's control instructions and real-time load pressure of the system, thereby infinitely adjusting the output flow rate and pressure, achieving the best match between engine power and hydraulic demand, and achieving efficient and energy-saving operation. The assembly includes the pump body, variable regulator (servo piston and feedback mechanism), drive shaft, and key seals, with precise structure and high reliability.

Daily inspection: Check the pump body for leakage and abnormal noise every 250 working hours, and monitor the system pressure and flow rate; Check the cleanliness of hydraulic oil every 500 working hours (recommended NAS level 8 or below), and replace the oil suction and return filter elements in a timely manner. Regular maintenance: Replace hydraulic oil (recommended ISO VG46 anti-wear hydraulic oil) every 2000 working hours and clean the oil tank; Check the clearance between the plunger and cylinder body every 4000 working hours (standard 0.01-0.03mm), and if it exceeds the standard, grind or replace the components. Troubleshooting: If there is insufficient output flow, pressure fluctuations, or abnormal noise, it is necessary to investigate whether the oil suction filter is blocked, the oil is contaminated, the variable mechanism is stuck, or the bearings are worn; It is strictly prohibited to operate under oil shortage or overpressure (>10% of rated pressure).