An accident during an overload test of a crane at a Liebherr yard in Rostock, Germany on May 2nd, which led to the crane’s collapse, was the result a broken crane hook provided by a third-party supplier, crane manufacturer Liebherr-MCCtec Rostock has said.
The crane collapse was on board Orion 1, a newbuild offshore wind installation vessel being built for DEME. Two people were seriously injured in the incident.
The accident happened during load testing of a 5,500-tonne capacity Liebherr-MCCtec Rostock HLC 295000 crane.
The Orion 1 is under construction by COSCO (QIDONG) Offshore. It arrived at the Liebherr construction yard last November for installation of the crane – which was the final phase in the construction process.
Liebherr-MCCtec Rostock GmbH managing director Leopold Berthold said that “we wish the injured persons all the best and hope for a full and speedy recovery. Considering the extent of the damages, we are above all thankful that it did not cause more personal injuries. Our priorities currently lie in fully supporting the investigating authorities in order to contribute to the quickest possible clarification of the accident”.
Liebherr said that the responsible authorities and experts unanimously agreed that a broken crane hook was the cause of the accident.
“The exact reasons as to why the hook did not withstand the load are unclear at this stage of investigations. The design and manufacture of the crane hook was purchased from an external supplier. A design or production error of the Liebherr crane can therefore be excluded,” the company said.
The overload test that led to the accident was planned for to reach 5,500 tonnes, the crane’s maximum capacity, however the failure of the crane hook took place at 2,600 tonnes, well below the maximum.
The Orion 1 was planned to install 103 jackets at the 950MW Moray East offshore wind farm in Scotland immediately upon delivery later this month.