Kobelco 1350 Crawler Crane Performance and Maintenance Overview

[MikePhua]

Kobelco’s Engineering Legacy and the 1350 Series
Kobelco Construction Machinery, a division of Kobe Steel Ltd., has been a pioneer in crawler crane development since the 1930s. Known for their precision engineering and robust steel fabrication, Kobelco cranes have earned global respect in infrastructure, petrochemical, and marine construction. The 1350 series crawler crane represents a high-capacity lifting solution designed for demanding environments where stability, reach, and reliability are paramount.
The Kobelco 1350 typically refers to a crane in the 135-ton class, often configured with a long boom, optional luffing jib, and advanced load moment control systems. These machines are used in bridge erection, wind turbine installation, refinery expansion, and port operations. By the mid-2010s, Kobelco had delivered hundreds of units worldwide, with strong adoption in Southeast Asia, the Middle East, and North America.
Core Specifications and Capabilities
Standard configuration of the Kobelco 1350 crawler crane includes:

• Maximum lifting capacity: 135 metric tons
  
• Main boom length: up to 76 meters
  
• Luffing jib option: up to 61 meters
  
• Engine: Turbocharged diesel, typically 6-cylinder, ~300 horsepower
  
• Operating weight: ~140,000 kg (varies by counterweight setup)
  
• Travel speed: ~1.2 km/h
  
• Swing speed: ~2 rpm
  

Terminology notes:

• Luffing jib: An angled extension of the boom that allows high-reach lifting with reduced tail swing.
  
• Load moment indicator (LMI): A system that calculates the crane’s lifting capacity based on boom angle, radius, and counterweight configuration.
  
• Counterweight: Removable ballast used to balance the crane during lifting operations.
  

Hydraulic System and Control Architecture
The 1350 series uses a closed-loop hydraulic system with multiple pumps dedicated to swing, hoist, travel, and boom functions. The system is governed by proportional control valves and electronic feedback sensors.
Key components include:

• Variable displacement piston pumps
  
• Pilot control valves
  
• Hydraulic oil cooler and filtration system
  
• Swing motor with planetary reduction
  
• Winch drums with multi-layer spooling
  

Common issues in aging units:

• Hydraulic drift in boom or jib
  
• Slow swing response due to pilot pressure loss
  
• Winch brake slippage under load
  
• Contaminated fluid causing valve sticking
  

In one case from a refinery expansion in Texas, a Kobelco 1350 experienced erratic boom movement. The pilot pressure was found to be 30% below spec due to a clogged filter in the pilot line. After replacement and fluid flush, control precision was restored.
Electrical System and Monitoring Reliability
The crane’s electrical system integrates analog gauges with digital fault monitoring. While robust, it can suffer from environmental wear, especially in coastal or high-humidity regions.
Typical faults include:

• Corroded connectors in the LMI harness
  
• Faulty swing limit switches
  
• Display flicker due to voltage instability
  
• Relay failure in the travel control circuit
  

Preventive measures:

• Use dielectric grease on all connectors
  
• Replace relays every 2,000 hours
  
• Install surge protectors on sensitive circuits
  
• Shield wiring harnesses from UV and abrasion
  

In Indonesia, a port operator added a secondary voltage regulator to stabilize the LMI display during monsoon season. This reduced false overload warnings and improved operator confidence.
Undercarriage and Track System Maintenance
The undercarriage of the 1350 includes heavy-duty track frames, rollers, idlers, and drive motors. Given the crane’s weight, undercarriage wear is a critical concern.
Maintenance checklist:

• Check track tension monthly (ideal sag: 40–50 mm)
  
• Grease rollers every 100 hours
  
• Inspect drive sprockets for tooth wear
  
• Replace track pads if cracked or bent
  
• Monitor travel motor temperature during long moves
  

Terminology notes:

• Track sag: The vertical drop between the top of the track and the carrier roller, indicating tension.
  
• Carrier roller: A roller that supports the top of the track chain, reducing wear and friction.
  

In Chile, a mining contractor extended undercarriage life by rotating track pads every 1,500 hours and using graphite-based grease on rollers.
Boom and Structural Integrity Checks
The boom and jib sections are fabricated from high-tensile steel and require regular inspection for fatigue and weld integrity.
Inspection points:

• Check chord members for cracks or deformation
  
• Inspect pin connections for wear or elongation
  
• Verify boom angle sensor calibration
  
• Grease all boom pivot points
  
• Conduct ultrasonic testing every 5,000 hours
  

In Poland, a bridge contractor discovered a hairline crack in a boom weld during routine inspection. Early detection allowed reinforcement before failure, avoiding costly downtime.
Parts Availability and Sourcing Strategies
While Kobelco maintains global support, parts for older 1350 units may require creative sourcing:

• Use serial number to match hydraulic and electrical components
  
• Cross-reference seals and filters with Parker, NOK, or Baldwin equivalents
  
• Seek remanufactured winch motors from crane rebuilders
  
• Join regional crane owner networks for surplus exchanges
  

In South Africa, a contractor rebuilt a swing motor using parts from a retired Kobelco 7150. The retrofit required minor machining but restored full rotation capability.
Operator Stories and Field Wisdom
In New Zealand, a wind farm crew used a Kobelco 1350 to install turbine nacelles in high wind conditions. The crane’s stability and smooth control allowed precise placement despite gusts exceeding 30 km/h.
In Florida, a marine contractor deployed a refurbished 1350 for dock piling. After upgrading the hydraulic seals and installing LED floodlights, the crane operated safely for 1,800 hours without incident.
Conclusion
The Kobelco 1350 crawler crane remains a formidable lifting machine with a legacy of performance in complex environments. With disciplined maintenance, targeted upgrades, and a deep understanding of its systems, operators can extend its service life and maintain safe, efficient operations. Whether lifting bridge segments or turbine blades, the 1350 continues to prove that precision and power can coexist in a single steel frame.