First showcased at bauma 2022, the AC 5.250-2 has since undergone further development to enhance its features, particularly in the area of safety. The crane’s impressive lifting capacities, ease of transportation and innovative technology make it a compelling choice for a wide range of applications, says Tadano, its manufacturer.

Ease of transportation combined with excellent lifting capacities were the primary development goals when designing the new AC 5.250-2 – which were already achieved in the prototype that was unveiled at the leading construction machinery fair in 2022 in Munich, Germany, it adds.

The AC 5.250-2 is claimed to sets standards in its class with the best lifting capacity of 250-tonner all-terrain cranes at 70 m main boom length. Its maximum system length of 112 m is best-in-class. All main boom extensions from 5.8 to 36 m are self-rigging. Its complete counterweight of 80 tonnes is mounted in only three lifts.  Also, thanks to IC-1 Plus, it can always use the maximum available lifting capacity and it stays within the 12-tonne axle load limit even with a 80-tonne hook block, says the company.

AC 5.250-2 leads the pack with a lifting capacity of 14.5 tonnes with a 70-m boom length at a radius of 12 to 24 m or 11 tonnes at a radius of 42 m with a boom length of 47 m at the very top. The 70-m main boom can be extended by 42 m with a HAV main boom extension, making it possible to reach a system length of 112 m, according to Tadano.

Sophisticated counterweight concept

The crane can pick up its total counterweight of 80 tonnes in three lifts: 49.6 tonnes with a full 360-degree radius of up to 6.2 m followed by two lifts of 15.2 tonnes, with each split into 10 and 5.2 tonnes for mounting on the right and left of the base package. If necessary, the counterweight can be split into smaller pieces as well, making it possible, for example, to pick up the 5.5-tonne base plate from a distance of up to 20.1 m across the full radius.

The AC 5.250-2 is powered by a state-of-the-art Mercedes-Benz engine with an output of 522 hp and a maximum torque of 2,600 Nm.

“Thanks to the IC-1 Plus crane control system, which comes as standard, the available radius can even be significantly increased at certain slewing angles,” Peter Kleinhans, Project Manager, underscores. “In addition, the fact that the counterweight can be split into a large number of elements with none weighing more than 10 tonnes ensures maximum flexibility for transportation logistics. This means that relatively small trucks can be used for transportation when required by space conditions at a work site.”

Taxi crane with 12-tonne axle load

The AC 5.250-2 offers outstanding transportation configuration options. For instance, it can carry a three-sheave hook block for lifting loads of up to 67.3 tonnes or a 5.8-m heavy-lift runner on board while remaining within a 12-tonne axle load configuration; the transportation mounts for the HAV extension are included by default in the 12-tonne axle load.

Moreover, a payload of several hundred kilogrammes at the rear end is possible. Hence, the crane can be used as a taxi crane without a support vehicle while remaining within the legal axle load limit of 12 tonnes. And if the axle load is increased to 16.5 tonnes, it can also carry up to 20 tonnes of its maximum counterweight, Tadano adds.

Latest Tadano technological features

The crane manufacturer designed the AC 5.250-2 to come with comprehensive equipment as standard, including the innovative IC 1 Plus crane control system. This system determines the crane’s maximum lifting capacity for every boom position as a function of the superstructure’s slewing angle, and in real time. As a result, the crane is able to take advantage of the maximum lifting capacity available to it – especially during lifts over the outriggers. In other words, the feature provides the greatest support when it comes to lifts in which the outriggers are not fully extended, and the counterweight is reduced. All in all, the AC 5.250-2 benefits from this tremendously, as its outriggers can be extended asymmetrically to 0, 25, 50, 75, and 100 per cent positions, Tadano points out.

In addition, the one-of-a-kind Surround View camera system, which makes it easier for crane operators to optimally position the crane at work sites, is also optionally available for the Tadano AC 5.250-2.

“With Tadano Surround View, crane operators can take a look at a display in the cab to know exactly how they need to position the crane at their work site in order to extend all outriggers sufficiently and ensure that they are using the required counterweight tailswing radius. This eliminates tedious and time-consuming measurements and testing when looking for a location from which to operate the crane, making the latter ready for use faster,” explains Kleinhans.

The system also provides assistance on the way to the work site by making it easier for crane operators to notice pedestrians and cyclists when turning.

Lift Adjuster – improved safety during operation

Next year, the AC 5.250-2 will additionally come with The Lift Adjuster, which is said to be one of a kind worldwide. The system consists of a technical control system that can be activated with the press of a button and that measures the boom’s deflection and independently adjusts the lift cylinder in order to compensate for the change in radius caused by the deflection and to eliminate the risk of swinging – thus significantly improving safety in the work environment.

Comfortable and safe workstation

To ensure the comfort of crane operators, all hydraulic components that emit noise are located away from the superstructure cab. Moreover, the spacious design behind both cabs ensures maximum operating comfort and a pleasant work environment. Intelligently positioned access points, attachment points for operators’ personal safety equipment, and a step that can be extended from the carrier to make it safe and comfortable to enter and exit the superstructure cab all contribute to the operator’s safety. Moreover, the hill start assist system, which comes as standard, ensures stress-free travel operation when driving up and manoeuvring on uphill slopes.

Environmentally friendly operation

The AC 5.250-2 is powered by a state-of-the-art Mercedes-Benz engine with an output of 522 hp and a maximum torque of 2,600 Nm that meets the latest EU Stage V emissions standards. Its Eco Mode ensures that the engine outputs the exact amount of power that the crane actually needs at any one time, with the IC-1 crane control system taking care of the corresponding calculations. In addition, the crane also has a fuel-saving start-stop feature on board, with the system turning off the engine at the press of a button but without deactivating the control software.

The state-of-the-art five-axle crane raises the bar in a large number of areas, providing it with tremendous versatility which, combined with an enormous reach and large lifting capacities, makes it ideal for erecting tower cranes and for construction projects of all types.