The hydraulic system is the heart of any excavator. It converts engine power into the digging force, speed, and precision that define machine performance. Understanding hydraulic systems helps you make smarter purchasing decisions.
Types of Hydraulic Systems
Open-Center Systems
Used in smaller excavators, open-center systems continuously circulate oil through the control valves. Simple and cost-effective, but less efficient at partial loads. Best for machines under 20 tons.
Negative Flow Systems
Popular in medium and large excavators, negative flow systems use a pressure differential signal to control pump output. Kawasaki negative flow systems, used in our MY220.8 and MY485.9, offer excellent fuel efficiency and smooth multi-function operation.
Load-Sensitive Systems
The most advanced conventional system. Load-sensitive hydraulics match pump output precisely to the operator’s demands, reducing fuel consumption significantly. Featured in our MY80.9 and across the medium range.
Electronically Controlled Systems
Our electric excavators (MY210EV through MY485EV) use electronically controlled hydraulic systems with precise proportional valves. These offer the finest control resolution and fastest response times.
Key Hydraulic Components
Main Pump
Variable displacement axial piston pumps are standard. Look for:
- Kawasaki K7V series — industry-leading reliability (used in MY750.10, MY1350.10)
- Kawasaki K5V series — excellent for medium-class machines
- Flow rate — higher flow means faster cylinder speeds and cycle times
Control Valves
Monoblock or sectional valves direct oil flow to cylinders and motors. Quality valves provide:
- Smooth, proportional control
- Low internal leakage for holding power
- Pressure compensation for consistent speed regardless of load
Hydraulic Cylinders
Double-acting cylinders for boom, arm, and bucket. Key specs include bore size, rod diameter, and stroke length — these determine force and speed.
What to Look For When Buying
- System pressure: Higher pressure = more force in a smaller package. Premium machines operate at 350+ bar.
- Pump flow: More flow = faster cycle times. Compare liters per minute at rated RPM.
- Filtration: High-quality filtration extends component life. Look for return-line and case-drain filters.
- Cooling: Adequate hydraulic oil cooling is essential for continuous heavy work.
MINGLIFT’s Hydraulic Advantage
Every MINGLIFT excavator features premium hydraulic components from world-leading suppliers. Our engineering team optimizes the complete hydraulic circuit — pump, valves, cylinders, and hoses — as an integrated system for maximum performance and efficiency.
Have questions about hydraulic specifications for a specific model? Get in touch with our technical team.