Terex quartet lift drilling support module

The module, which was the platform's heaviest component at 1,126 tonnes, was first lifted to a height of 18 m and then moved a distance of 51 m, making it necessary for the four Terex cranes to operate at up to 95 percent of their lifting capacity. This posed a daunting challenge to both the machinery and the people involved in the operation, saysTerex.

Two of the four Terex CC 2800-1 units were delivered by DAS Otomotiv, which is an authorised distributor for Terex in Turkey and Azerbaijan, and is also in charge of training Hareket's team for assignments involving the CC 2800-1.

The team spent a total of eight days configuring the cranes so that they would be ready for use, preparing the ground accordingly, and carrying out the lift.

"In order to make paths that would be sufficiently strong for the cranes, we had to bring in large amounts of fill material on trucks and compact it with road rollers and vibratory plate compactors, which our team did for a full twelve hours each day," said Bob Parker, BP heavylift superintendent said.

The weather was just as unforgiving: The lift could not be performed safely unless the wind speeds in the area fell below eight metres per second, and the team had to wait two long days before meteorologists finally forecast a six-hour window during which this condition would be met.

The four CC 2800-1 cranes were set up identically (with an SSL configuration, a 60 m main boom, and a 400 tonne counterweight) with one exception: two of them had a Superlift counterweight of 300 tonnes, while the other two had a Superlift counterweight of 250 tonnes.

The reason for this arrangement was simple: The DSM's centre of gravity was not centred, as the module was heavier on one side than on the other. In order to effectively counter this imbalance, the two cranes on the lighter side worked with a smaller counterweight and a steeper boom angle, meaning that they also worked with a smaller radius. As an additional measure, the team adjusted the pad-eyes on the drill support module in order to prevent it from being "skewed." The last elements responsible for ensuring that everything would go according to plan were the cranes' load moment indicator (LMI), which would let each crane operator know the exact weight on the hook at all times during the lift.

The fact that the complex lift operation went smoothly did not surprise Parker one bit: "I've been in the business for 38 years, 28 of them as a manager, and I can tell you that when I look at all the experiences I've had with the CC 2800-1, I know one thing: this crane is not only an exceptional machine, but also one that I would trust with any lift, no matter how challenging."

www.terex.com