Advanced lifting

The project involved a total of 143 lifts, 31 of which were carried out using the 1,600t capacity Terex CC 8800-1 crane.

For two lifts, installing two AGR (Advanced Gas Reactor) absorbers each weighing 1,300t, the crane worked in its Twin format.

The lifts were planned by Al Jaber site manager Sevi Phillip over a period of 18 months. The requirements of the two AGR lifts were critical to the company being awarded the contract. With the single boom 1,600t capacity CC 8800-1 crane already on site to carry out the smaller capacity lifts, the crane was then adapted to SSL Twin configuration by adding the second boom to lift the two AGRs.

With the CC 8800-1 fully rigged in Twin format, the self-propelled modular trailers used to move the huge columns into position were also assembled. Each absorber was raised from the horizontal to the vertical using the CC 8800-1 Twin as the main lift crane and using a tail frame to control the base of the AGR.

Once the CC 8800-1 Twin lifted the absorber clear of the SPMTs, the trailer was moved out of way and the lift continued until the column was vertical. At this point the tail frame was, removed leaving the crane to carry the whole weight of the AGR.

Next the crane slewed through 90° and placed the column into its final position on the specially prepared foundation. The Twin was then partially de-rigged so that it could track a short distance into the correct position to carry out the second lift and then be reassembled to carry out the identical lift sequence with the second AGR.

Mark Rowlands, project manager with Al Jaber Heavy Lift, said that the contract was further complicated because of the intense heat in the summer and wind variations. He said, "The Terex CC 8800-1 Twin was comfortable, easy to use, stable and flexible and the operators were very happy with its precise and user friendly controls."

"We were all very pleased with the crane and how it performed. Everything went according to plan," said Phillip. "We were all surprised how compact the CC 8800-1 Twin was given its huge lift capacity.

There were 27,000 people on site so space was at a premium. We worked with the client to minimise time and space requirements which really benefitted the whole project."

The AGR column is a critical part of the liquefied natural gas processing train helping remove hydrogen sulphide, carbon dioxide and organic sulphurs in the raw feed gas so it complies with LNG liquefaction process or sales gas production standards.

Alex Mullins, executive director of Al Jaber Heavy Lift Group responsible for all international activities, said that the project was an example of the excellent working relationship with Terex. "We strive to provide clients with safe, cost effective projects and use the right people and equipment to ensure the right outcome. We were involved at an early stage with the development of the Terex CC 8800-1 Twin and we are very pleased with the end result."