Bespoke gantry performs ALE’s biggest Peruvian lift26 September 2011
UK firm ALE has successfully completed its heaviest Peruvian lift, a 463t de-ethaniser column being installed for the Malvinas Gas Plant expansion project.
Installation of the 51m-tall de-ethaniser column would have provided a difficult task for the lifting contractor if attempted by conventional means due to the plant’s location in the Peruvian jungle.
Crane access routes were limited, as was the supply of local cranes, so to avoid the cost of importing machinery, ALE used a two-tower gantry system stabilised by strand jacks.
ALE’s bespoke design for the 60m gantry consisted of two 500t lifting units along with a 500t hydraulic lifting unit fitted to a tailing gantry used for retaining.
Project manager Hernán Asensio explained: “We developed the self-erecting gantry so that it could be fully assembled on site to adapt to the limited river transportation — there were also no existing roads to the site”.
Another benefit to using this gantry system was that the amount of plant on site was reduced compared to use of a typical ‘A-frame’ system, providing less handling time and increasing leeway in the project schedule.
Setup of the main lift gantry of the system required a small local crane to lift one end 30° from the ground. At this point the uprighting gantry and strand jacks took over to lift the gantry the remaining 60°. After self-assembly of the gantry system, the uprighting gantry was then reconfigured to perform its role during the de-ethaniser column’s installation as a tailing gantry.
Using this system, the entire installation process was eventually completed in nine hours.