Spotlight on safe loads and working near water

In our March issue we explored executing crane lifts safely on and around water, and this issue we’re talking about secure transportation of loads. Smithbridge Group’s project to relocate three fuel tanks from Bell Bay to Newcastle safely and effectively tackled both these challenges. Smithbridge was contracted to move three large fuel tanks each weighing 420 tonnes from the decommissioned Hydro Tasmania Bell Bay Power Station to Mayfield Terminal in Newcastle. The project provides a practical example of good practice when transporting complex loads, as well as planning and executing crane lifts nearby to water.

Smithbridge worked closely with two specialist consultants to ensure there was appropriate planning for this highly complex relocation. Melbourne-based Constructioneering was engaged for structural engineering to ensure the load was safe to lift. As we discussed in the March edition of Lifting Matters, an all-important naval architect and marine engineer was also engaged, International Maritime Consultants, for the marine engineering and tow plans.

Before the tanks could be relocated, assessments had to be conducted to ensure the tanks could structurally withstand being moved. Constructioneering conducted this assessment, and the resulting methodology involved cutting into the tank to remove existing pipework and oil waste, then reinforcing the tanks with support beams and vertical tensioned steel tendons.

Transportation

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After they were prepped for transport, the tanks were individually jacked high enough for a customised transport frame and self-propelled trailer system to be placed beneath them. The transport frame was designed in‐house by Smithbridge engineers using Bailey bridge trusses running between fabricated headstocks, supported laterally across the tanks. The frame was placed on four trailers, one on each corner of the frame, with a jacking height of 3.5m to allow the tank shell to maintain clearance from sea swell during travel and clear any safety rails.

Loading onto barges

A custom-built jetty was required that could sustain the load of the self-propelled trailers and tanks, to enable the tanks to be loaded onto the barge. Smithbridge mobilised a 150t Kobelco crawler crane and a 50t Grove rough terrain crane to assemble two parallel 48 m jetties at Bell Bay for this purpose.

The tanks were supported on braced support stools during jacking. They were jacked 150mm at a time using an airbag system until they were approximately 3.5m off the ground. 

The chosen vessel was a 76 metre by 24 metre dumb barge. The barge design included pedestals welded to the deck, which the shell of each tank rested on. To allow for the flexing of the barge on the ocean, the tank was not fixed onto the pedestals but was secured using support bollards and engineered stops.

The ocean journey

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The size of the tanks meant that individual journeys had to be made for each one.
After the 579 nautical mile journey, the tanks were unloaded directly onto the wharf in Newcastle with water ballast used to tilt the deck of the barge to align it with the wharf. Once the self-propelled trailers were safely back on dry land, they transported the tanks over 1.5km to the destination at the Mayfield Terminal.

Safely delivered through extensive planning

Smithbridge worked with qualified and certified specialists on the structural and maritime aspects of this project. Lifting and moving anything near or on the water is high risk, particularly unusually large or heavy items. The combined planning effort on this project meant the team achieved turnaround times of 50 to 58 hours in Newcastle and Bell Bay.

Sally Austin