28.02.2009

Moving a 250 tonner

A 250 tonne Demag AC665 All Terrain crane tipped over at the Laverton Power station, on the outskirts of Melbourne, Victoria, last week while it was being moved with boom raised and full counterweight installed.
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The cranes counterweight came to rest in the sand

The crane, which is owned by Dandenong based Customlift Services, was travelling with the superstructure in its normal travel position. However with no mechanical house lock in place and the boom raised, when the crane chassis edged out of level, the large counterweight apparently pulled the superstructure around so that the counterweight was over the side, resulting in it tipping over backwards.
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The outriggers were only slightly extended

The counterweight came to rest in the sand, just as the slightly extended outrigger jacks came into contact with the ground.

On the surface it looks as though little damage was done, and a very steady and careful operator might even be able to right the crane without the need for an external recovery vehicle.
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A view from the front

Customlift Services is a division of OD heavy transport group of Dandenong, South East of Melbourne.

Vertikal Comment

The facts that we were sent did not go into a great deal of detail, but one has to ask the following questions.
- Why were the outriggers not extended a little more to act as stabilisers?
- Why was the boom not placed in the cradle for travel and not raised until the outriggers were fully set?
- Why did the slew brake not hold the superstructure?