Kobelco RK120-2 / RK120M-2

The Kobelco RK120-2 and RK120M-2 represent Kobelco’s versatile entry in the lightweight rough terrain crane market, engineered for both reliability and flexibility. The RK120-2 is rated at 12,000 kg at 2.0 m with an 8-part line, whereas the RK120M-2, with a more compact configuration, handles 4,900 kg at 4.0 m with a 4-part line. The main boom on both machines spans from 5.3 m to 23.8 m, composed of six box-type sections with synchronized hydraulic extension using wire rope assistance.

For extended reach, a 3.6 m or 5.5 m jib can be deployed, featuring a hydraulic tilt function between 5° and 45°. With the jib in use, the maximum hook height is 30.0 m, and the operating radius extends up to 23.2 m. The cranes boast excellent lifting speeds—main winch operations range from 110 m/min standard to 185 m/min in high-speed mode, with the auxiliary winch reaching up to 160 m/min.

Slewing operations are precise and smooth, driven by a hydraulic motor and planetary reduction system, offering a rotation speed of 2.4 rpm. Outriggers are adjustable in either H-type or X-type formats with five different extension widths for optimal stability, including a maximum span of 4.7 m. These configurations allow the crane to operate with full rated capacity even on varied surfaces.

Powering the carrier is the Mitsubishi 4M50-TLE2A, a 4.899-liter, 4-cylinder, turbocharged diesel engine producing 125 kW (170 PS) at 2,800 rpm and 451 Nm of torque. The drivetrain is selectable between 4×2 and 4×4 with a power-shift automatic transmission offering 3 forward and 1 reverse speeds with High/Low ranges. Suspension is composed of longitudinal leaf springs, with a maximum traveling speed of 49 km/h and a tight minimum turning radius of 6.5 m.

The crane is equipped with a full suite of safety systems, including overload shutoff, anti-two block, slewing interlock, work area limiter, and outrigger width sensors. Optional extras include work lighting, auxiliary warning lights, and a power tilt jib, enhancing safety and operator awareness. Operator comfort is also emphasized with features like a fully adjustable seat, power windows, air conditioning, and user-friendly pedal and lever layout.

Together, the RK120-2 and RK120M-2 are ideally suited for urban construction, utility works, and plant operations where access is limited, yet lifting demands remain substantial. The two models provide a flexible solution that balances power, precision, and portability in rough terrain environments.