The main hydraulic pump used in the Hitachi EX120-1 excavator is typically a variable displacement axial piston pump.
This type of pump is chosen for its ability to vary the output flow rate and pressure according to the load and demand, making it highly efficient in various operating conditions.
Flow Rate:
The flow rate of the main hydraulic pump is a crucial specification. It determines the amount of hydraulic fluid that the pump can deliver per unit of time. In the case of the EX120-1, the flow rate typically falls in the range of 150 to 180 liters per minute (LPM). This flow rate is essential to ensure that the excavator can perform its various functions smoothly and efficiently.
Pressure Rating:
The hydraulic pump must generate sufficient pressure to operate the hydraulic cylinders and motors effectively. The main hydraulic pump for the Hitachi EX120-1 usually operates at a pressure rating of around 3000 to 3500 pounds per square inch (psi), or approximately 210 to 240 bar. This high-pressure output is necessary to power the excavator's heavy-duty hydraulic systems.
Mounting Type:
The main hydraulic pump is typically mounted directly to the engine of the excavator. This ensures a direct mechanical connection and efficient power transfer from the engine to the pump, minimizing energy losses.
Control Mechanism:
Many modern excavators, including the Hitachi EX120-1, feature a load-sensing hydraulic system. This system adjusts the pump's output based on the load and demand, optimizing fuel efficiency and reducing wear and tear on the hydraulic components. The control mechanism of the main hydraulic pump may include a pressure compensator and a flow control valve.
Efficiency:
Efficiency is a critical factor in the design of the main hydraulic pump.
High efficiency not only reduces fuel consumption but also minimizes heat generation within the hydraulic system. Most hydraulic pumps for excavators are designed to operate with high overall efficiency, often exceeding 90%.
Maintenance Requirements:
Proper maintenance of the main hydraulic pump is essential to ensure its longevity and reliability. Regular inspection and maintenance may include checking for leaks, monitoring fluid levels and quality, and replacing filters as needed.
Compatibility:
The main hydraulic pump for the Hitachi EX120-1 must be compatible with other hydraulic components and systems in the excavator. This includes compatibility with hydraulic hoses, valves, cylinders, and the excavator's control system.
Durability and Reliability:
Durability is a crucial factor for any hydraulic pump in heavy machinery like excavators. These pumps are subjected to high loads, vibrations, and challenging working conditions. The main hydraulic pump for the Hitachi EX120-1 is designed to be robust and reliable to ensure long-lasting performance in demanding construction and excavation applications.
