Kobelco 7250S

The Kobelco 7250S crawler crane is a powerful 250-ton class model developed for robust heavy-lift applications in construction, industrial, and infrastructure projects. Designed to meet modern demands, this crane combines long boom reach, superior control systems, and ease of transport with high safety standards.

At its core, the Kobelco 7250S is powered by a HINO P11C-VH, a 4-cycle, water-cooled, 6-cylinder turbocharged diesel engine delivering 271 kW at 1,850 rpm. This engine is supported by a 400-liter fuel tank and a water-cooled system, ensuring consistent performance across extended operations. The hydraulic system is driven by four variable displacement piston pumps, with a maximum pressure of 31.9 MPa, and a large 650-liter hydraulic tank ensures smooth operations across all functions including boom hoisting, swing, and propel.

In terms of structural capabilities, the main lattice boom can extend from a minimum length of 15.2 meters up to 76.2 meters. It features tubular high-tensile steel chord construction with pin connections, ensuring strength and flexibility across its operating range. For extended lifting applications, the 7250S offers a fixed jib up to 30.5 meters and a tower jib configuration with a total length of 51.8 meters, providing a maximum lifting height combination of 91.4 meters. The long boom configuration further extends reach with a 37.5-ton rated capacity at 14.4 meters boom length.

The crane’s hoisting system includes a dual drum setup with grooved drums for 28 mm wire ropes, capable of handling up to 390 meters on the main drum and 220 meters on the auxiliary. Hoisting and lowering speeds range from 26 to 2 m/min, with a rated single-line pull of 132 kN and a maximum pull of 251 kN. A spring-set, hydraulically released multiple disc brake system ensures safe braking across all hoisting operations, supported by external ratchet drum locks for enhanced safety.

On the lower structure, the 7250S features a steel-welded carbody with independent crawler drive for each side, delivering reliable traction and maneuverability. The crawlers come with 1,070 mm wide flat shoes and a maximum gradeability of 30%, making the crane suitable for uneven and rugged terrain. The design also includes quick-disconnect axles for simplified transport and mobilization.

The swing system provides full 360° rotation with hydraulic motors and planetary gear reducers, offering a swing speed of 2.2 min⁻¹. A hydraulically released spring-set brake ensures secure positioning during lifting operations.

The operator’s cab is fully enclosed with safety glass and fitted with a high-back adjustable seat, air conditioning, footrests, windshield wipers, and other ergonomic fittings, ensuring a comfortable and safe working environment. The redesigned torsion-free upper structure supports low-noise operation and easy servicing of engine components.

In terms of weight, the total operating mass of the 7250S is 212 tonnes, including 97.1 tonnes of counterweight and 23.1 tonnes of carbody weight. The transport weight of the base machine, with boom base and winches, is approximately 45.2 tonnes, and the ground pressure is rated at 123 kPa.

Altogether, the Kobelco 7250S represents a highly capable and transport-efficient 250-ton crawler crane. It brings together strong lifting performance, extensive reach, and advanced mechanical systems, positioning it as a reliable machine for global heavy lift applications outside of Japan, Europe, and North America.