Hydraulic Piping and System Overview of the Hitachi EX60-2 Excavator

[MikePhua]

Introduction
The Hitachi EX60-2 is a compact hydraulic crawler excavator renowned for its versatility and efficiency in various construction and excavation tasks. Understanding its hydraulic piping system is crucial for maintenance, troubleshooting, and ensuring optimal performance.
Hydraulic System Components

1. Hydraulic Pumps: The EX60-2 is equipped with variable displacement axial piston pumps that provide the necessary hydraulic flow for various functions.
   
2. Control Valves: These valves direct the hydraulic fluid to different actuators, controlling the movement of the boom, arm, bucket, and swing functions.
   
3. Hydraulic Cylinders: Cylinders are responsible for the linear motion of the excavator's components, such as the boom and arm.
   
4. Hydraulic Hoses and Piping: These are the conduits through which hydraulic fluid flows, connecting the pumps, valves, and actuators.
   
5. Filters and Coolers: To maintain fluid cleanliness and temperature, the system includes filters and coolers that ensure longevity and performance.
   

Hydraulic Circuit Diagram
A comprehensive hydraulic circuit diagram is essential for understanding the flow paths and troubleshooting potential issues. While specific diagrams for the EX60-2 can be found in the service manual, a general overview includes:

• Pump to Valve Block: The hydraulic pump delivers fluid to the valve block, which distributes it to the appropriate actuators.
  
• Pressure Relief Valve: This component ensures the system pressure does not exceed safe limits, protecting components from damage.
  
• Hydraulic Cylinders: Fluid flow into and out of cylinders controls the movement of the excavator's parts.
  
• Return Lines: After performing work, the hydraulic fluid returns to the tank through return lines.
  

Troubleshooting Tips

1. Unusual Movements or No Response: Check for air in the hydraulic lines, low fluid levels, or clogged filters.
   
2. Overheating: Inspect the cooler for blockages and ensure proper fluid levels.
   
3. Leaks: Examine hoses and connections for wear or damage.
   

Maintenance Recommendations

• Regular Fluid Checks: Monitor hydraulic fluid levels and quality to ensure efficient operation.
  
• Filter Replacements: Replace filters at recommended intervals to maintain system cleanliness.
  
• Component Inspections: Regularly inspect hoses, cylinders, and valves for signs of wear or damage.
  

Conclusion
The hydraulic system of the Hitachi EX60-2 excavator is integral to its performance and longevity. Understanding its components and maintenance needs ensures the machine operates efficiently, minimizing downtime and repair costs.