May 11 - Jumbo's heavy lift vessel Jumbo Javelin has shipped two huge accommodation modules from Trogir in Croatia to Limbe, Cameroon for oil and gas company Perenco.

Before the shipment began, a 3D study was conducted by Jumbo engineers to ensure that the accommodation modules, each of which were four storeys high and measured 30 m x 20 m, would fit on the vessel's deck using three lifting beams.

In Trogir the two modules, together weighing over 750 tonnes, were lifted onboard Jumbo Javelin using its two 800-tonne capacity cranes.

Jumbo explained that it encountered several challenges during the project, including draft restrictions in Trogir and extremely small lifting clearance of less than 0.5 m during both the loading and unloading operations.

At the port of Limbe, the modules had to be placed directly onto a jacked up oil rig in Cameroon, said Jumbo. Due to limited lifting height and tidal restrictions, the rig was ballasted at a draft of 2.5 m in the water.

The distance between the jacked up rig and Jumbo Javelin had to be very precise in order to position the accommodation modules onboard, explained the heavy lift shipping company. A bespoke bumper system installed on the rig's deck ensured that the accommodation blocks were safely placed on their supports.

The heaviest module weighed in at 414.8 tonnes, but had a total weight of 511 tonnes with its 96 tonnes of rigging; while the slightly smaller module weighed 355.7 tonnes, with a total weight of 451 tonnes including 95 tonnes of rigging.