Hitachi-Sumitomo ST400M

The Hitachi-Sumitomo ST400M is a robust 40-ton lattice boom truck crane designed for medium to heavy lifting tasks in various industries such as construction, infrastructure, and industrial maintenance. With a maximum lifting capacity of 40 tons at a 3.6-meter load radius, the ST400M provides powerful lifting capability and stability for demanding job sites. The crane’s lattice boom design ensures both strength and lightweight performance, allowing for maximum lifting reach and reduced structural weight. The standard boom length is 9 meters, with optional extensions available up to 31 meters, providing versatile reach for various lifting needs.

The superstructure of the ST400M features a precision-machined upper revolving frame, ensuring smooth rotation and long-lasting durability. The turntable is equipped with an integral swing gear, bolted to the carrier deck, ensuring precise movement during slewing. The “Speed-O-Matic” hydraulic control system provides smooth and efficient crane operation. This system includes a gear pump that maintains constant oil pressure, ensuring reliable operation of the boom, winches, and swing system. The control valves allow for easy regulation of pressure to the clutches and brakes, providing responsive and safe crane movements.

The drum system includes both front and rear main drums, with an optional third drum for additional lifting or auxiliary functions. The drums are equipped with grooved drum lagging and hydraulic brakes to ensure controlled lifting and lowering of loads. The brakes are external contracting band types, automatically engaging when the control lever is in neutral, providing a secure hold for suspended loads.

The boom hoist mechanism utilizes a spur gear drive system with independent clutch controls for precision raising and lowering of the boom. The crane’s swing system is driven by a spur gear with two clutches that transmit power to the swing pinion, providing smooth slewing motion. The swing system is equipped with an external contracting band brake, hydraulically released for precise control, and a manual lock mechanism to secure the boom during stationary operations.

The ST400M is powered by a Mitsubishi 6D14T diesel engine, a 6-cylinder, water-cooled, 4-cycle engine with a turbocharger for increased power and fuel efficiency. The engine produces 88.3 kW (120 PS) at 1,850 rpm, with a maximum torque of 500 Nm at 1,400 rpm, ensuring sufficient power for both lifting operations and travel. The engine is paired with a 3-speed transmission, allowing for power-shift operation and smooth transitions between gears during crane operation.

The crane carrier is built on a Nissan KL6S32SN chassis with an 8×4 drive system, providing excellent traction and mobility on job sites. The rear axles feature full-hanging, in-line tandem suspensions with longitudinal springs, ensuring smooth travel and stability during lifting operations. The ST400M has a top travel speed of 65 km/h, making it suitable for transport between job sites, while its turning radius of 10.9 meters provides good maneuverability in tight spaces. The crane has a gradeability of 0.48, ensuring it can handle slopes and uneven terrain effectively.

The outriggers are hydraulically operated, extending up to 6,200 mm for maximum stability during lifting operations. These outriggers can be deployed simultaneously or individually, depending on the terrain, and are controlled from either side of the carrier with a level gauge for precise placement. For additional safety, the crane includes a retractable gantry for counterweight management, ensuring stable lifting even under full load conditions.

The operator’s cabin is designed for safety and comfort, featuring full safety glass panels for excellent visibility. The cabin is equipped with ergonomic controls, including joysticks and levers for easy management of all crane functions. The operator also benefits from a well-ventilated space with an insulated design, reducing noise and heat for improved comfort during long shifts.

Safety features on the ST400M include a load moment limiter (LML), boom over-hoist limiting devices, drum pawl locks, and automatic brakes, ensuring safe operation under all conditions. The pneumatic brake system provides strong and reliable stopping power, while the auxiliary exhaust and engine compression release brakes add additional control when driving or lifting.

In summary, the Hitachi-Sumitomo ST400M is a highly capable 40-ton lattice boom truck crane that combines advanced hydraulic controls, powerful engine performance, and comprehensive safety features. Its versatility and durability make it ideal for medium-to-heavy lifting tasks in construction, industrial, and infrastructure projects.