Wolff launches low top tower crane
By Alex Dahm10 January 2022
Tower crane manufacturer and rental company Wolffkran has revealed its first 800 tonne-metre class saddle jib crane.
Increasing the use of prefabricated components means larger tower cranes are needed to lift them into place on construction projects. Wolffkran has responded with its largest saddle jib crane to date, the new Wolff 8076 Compact. Compact in the name refers to the tower head, or cat head, above the horizontal jib. It is around 10 metres lower or shorter than a conventional design, the company said.
Capacity is 40 tonnes and the maximum jib length is 80 metres, at the end of which the crane will lift 8.4 tonnes.
“We wanted to design a large yet economical crane and get the maximum capacity out of the steel structure. That’s why we opted for a low-top design, which we call Compact,” explained Wouter van Loon, Wolffkran product manager.
Another first is the use of four chords in the first three sections of the jib instead of the usual three-chord design. “This allowed us to optimise the transfer of forces along the jib and reduce individual component weights, resulting in around 40 per cent higher lifting capacity than with the three-chord design,” van Loon said.
The four chord jib and low top tower head allow the crane to be erected by a 350 tonne capacity wheeled mobile crane.
Using the 2.9 x 2.9 metre TV 29 tower on top of the TV 33 tower system, a maximum freestanding height of 100 metres can be achieved.
The 132 kW HW 40132 FU winch gives a maximum hoisting speed of 95 metres per minute to help minimise load cycle times. With the maximum load of 40 tonnes the hoisting speed is 17 m/min on two falls.
Depending on jib length it is possible to reduce the counter jib from 30.3 to 22.3 metres. As with the lower cat head this counter jib reduction helps where multiple cranes are working in close proximity. On a 55 metre jib with shortened counter jib the tip load capacity is 16.6 tonnes.
Further models along the same lines are in development, “We are evaluating a heavier lift version of this model, as well as one with a longer reach,” van Loon said. They will use the same basic components as the new 8076 Compact.