Wolffkran is promoting its new technically modified Wolff 6020 clear crane, which is claimed to offer customers the highest degree of flexibility and safety in the 140 metre-tonne range. The new model replaces the Wolff 6015 clear that was introduced in 2008.

Major improvements in the Wolff 6020 clear include an increased tip load capacity and the integration of numerous design details of the latest Wolff clear models.

Wolffkran decided to completely overhaul the successful Wolff 6015 clear due to the continuously growing demands on tower cranes and the increasingly complex challenges faced on construction sites.

The new flat-top saddle jib is offered as the six-tonne version Wolff 6020.6 clear and the eight-tonne version Wolff 6020.8 clear, with three different tower connections per version.

Gerd Tiedtke, product manager at Wolffkran says: “Compared to its predecessor, the six-tonne version can lift two tonnes instead of 1.5 tonnes at the tip at a 60-m jib radius, while the tip load capacity of the eight-tonne version has been increased from 1.5 tonnes to 1.8 tonnes.”

The Wolff 6020 ... a new guide roller on the jib optimises the run of the trolley.

Like the Wolff 6015 clear, both versions are designed for a pure two-fall operation.

“A feature that is particularly worth mentioning is the new 28 kW hoist winch Hw 628.1 FU installed in the Wolff 6020.6 clear, allowing for even faster working times with partial load speeds of up to 108 m per minute. The eight-tonne version relies on the tried-and-tested 45 kW hoist winch Hw 845 FU,” he says.

In line with the company’s design principle of keeping things simple, Wolff engineers redesigned the trolley by replacing the rollers with wheel flanges used to date by rollers without wheel flanges and a new guide roller on the jib, thus optimising the run of the trolley. The connection of the lower belt of the jib has also been redesigned to optimise the transfer of forces on the jib. This allows for the use of smaller, more practical bolts, which makes the assembly easier, Tiedtke explains.

The new Wolff 6020 clear also offers customers more flexibility. Since the counterweights are no longer included as standard in the basic crane package or the jib extensions, the customer can use counterweight blocks from his existing Wolff fleet, or buy these separately as required, which is a decisive advantage.

In terms of variability, the 6020 clear does not break with the tradition of its predecessor, and will be available with three different tower connections. It can, therefore, be connected to the narrow UV 15 tower system (external dimension of 1.5 m by 1.5 m) as well as to the wider towers TFS 20 and UV 20 (both 2 m by 2 m).

The counter jib has support beams for the easy positioning of the bracing rods.

“Inspired by customer feedback, we have fitted the counter jib with transport aids in the form of a special support structure to securely hold up to three jib sections on the counter jib during transport,” says Tiedtke.

Furthermore, the counter jib has been fitted with new railings that are suitable for attaching safety harnesses thus improving the safety for technicians working on the counter jib. The Wolff 6020 clear now also features the support beams for easy positioning of the bracing rods that were introduced to the clear models several years ago and considerably facilitate assembly of the counter jib. A maintenance crane with a lifting capacity of up to one tonne is optionally available to support maintenance work on the hoisting drive unit.

In comparison to the Wolff 6015, the Wolff 6020 clear features even more galvanised parts, such as railings, platforms and covers, as well as specially coated bolts to prevent corrosion. The modern slip ring system at the transition point between the tower and the jib permits trouble-free transmission of electrical signals.

“The electronic overload protection with Wolff Boost, the latest generation of frequency inverters in the hoist drive, the anti-collision interface, the hoisting gear with automatic power reduction as well as the telecommunication system Wolff Link are technical features that can only be sourced together from Wolffkran,” concludes Tiedtke.