Spierings SK 598-AT5

The Spierings SK 598-AT5 was developed to address projects that sit between compact city cranes and the heavier multi-axle classes, where higher load moments and reach are required without the complexity of six- or seven-axle transport. Built by Spierings, the SK 598-AT5 follows the company’s core design philosophy of delivering true tower crane working characteristics on a fully road-going chassis, optimized for flexibility and rapid deployment.

The crane is mounted on a five-axle carrier, which provides a well-balanced compromise between mobility and stability. Compared with four-axle machines, the additional axle allows higher permissible operating and transport weights, while still keeping overall length and maneuverability within practical limits for urban environments. Multiple steerable axles give the SK 598-AT5 good agility when negotiating narrow access roads and confined construction sites, with road travel speeds typically up to around 80 km/h.

The superstructure is equipped with a lattice jib designed for trolley operation, offering a working radius generally in the region of approximately 50 metres, depending on configuration. At short radii, the SK 598-AT5 delivers a maximum lifting capacity of around 8 tonnes, making it suitable for handling heavy formwork, concrete elements, and prefabricated components. At larger radii, the crane maintains practical capacities for everyday material handling on medium- to large-scale projects. By setting the jib at steeper angles, the crane achieves increased hook heights, enabling efficient work on multi-storey residential and commercial buildings.

A defining feature of the SK 598-AT5 is its fully automatic, one-man erection system. The crane can be erected at the push of a button, following a controlled and compact assembly curve that minimizes the space required around the machine during setup. This allows erection close to existing structures or within tight site boundaries where conventional tower crane assembly would be difficult. Once erected, the crane can remain standing between work phases without dismantling, improving productivity on projects with intermittent lifting requirements.

All crane working motions—including hoisting, slewing, trolley travel, and erection—are electrically driven. Electrical power is supplied either by an onboard diesel generator or via an external site power connection. When external power is used, the SK 598-AT5 operates with very low noise and zero local emissions, which is particularly advantageous in city-center locations and noise-sensitive environments. The electric drive system provides smooth, stepless control, delivering precise load handling comparable to that of a traditional top-slewing tower crane.

The crane is supported by a four-point hydraulic outrigger system with automatic leveling and electronic inclination monitoring. Several outrigger base widths can be selected to suit site conditions, balancing available space with required lifting performance. The five-axle carrier and well-distributed mass contribute to stable and predictable handling across the crane’s working range.

The operator’s cab is designed to tower crane standards, offering good all-round visibility, ergonomic controls, and a comfortable working environment for long shifts. Integrated monitoring and safety systems provide continuous feedback on crane configuration, load status, and wind conditions, supporting safe and efficient operation.

Overall, the Spierings SK 598-AT5 can be described as a versatile and capable mobile tower crane that bridges the gap between compact urban machines and heavier large-axle models. Its combination of five-axle mobility, fast self-erection, electrically driven crane functions, and solid lifting performance makes it well suited for demanding urban construction projects where reach, capacity, and flexibility are all critical.