The motor vessel Industrial Achiever, a specialized Roll on - Roll off semi-submersible vessel, recently loaded two massive Cold Boxes for an LNG plant under construction in West Africa. Built at a fabrication plant in New Iberia, Louisiana, the 700-ton boxes were transported to Houston by barge where they were trans-loaded to the Industrial Achiever for the subsequent ocean journey to West Africa.
The Cold Boxes loaded onto the Industrial Achiever on a roll on basis from barge to ship utilizing the vessel’s Ro-Ro ramp capable of handling pieces up to 1,200 metric tons. This operation was performed by self-propelled multi axle heavy lift trailers (SPMTs). As the trailers slowly moved across the ramp and onto the ship, the computer controlled resting pads automatically adjusted up and down to keep the pressure of load equalized across the length of the cold box.
“The pace of the loading operation is extremely slow as not only are the pressure pads on the SPMTs constantly adjusting to maintain equalized pressure, but the vessel is constantly transferring water between its ballast tanks. This ballast transfer counteracts the ever increasing weight that is rolling across the stern to keep pitch of the vessel constant” commented Captain Bert van der Laan, Intermarine’s port captain.
“Once in position, the boxes were lowered onto specially fabricated stands that hold the box such that the trailers may be removed. These stands are specifically positioned to transfer the weight of the boxes into the structural ribs of the vessel. The box is then heavily secured in place to eliminate any shifting while at sea” continued Captain van der Laan.
Although appearing rather simple, this operation required hundreds of hours of detailed engineering work to determine all the potential forces involved, the strength and placement of the stands and securing materials, and the overall stability of the vessel. Once completed, this plan was thoroughly reviewed and accepted by the vessel master, the cargo owners, warranty surveyors and the stevedores to insure all aspects were covered.
This type of heavy lift transport is a hallmark of Intermarine capability. Operations such as this have been performed by Intermarine throughout the world and with pieces weighing more than 1000 tons.
Intermarine offers regular services in the Americas, intra-Asia and Europe as well as constructs customized project voyages worldwide.