Smithbridge Group transports tanks to Newcastle
By Laura Hatton05 April 2013
Three large fuel tanks measuring 36 metres in diameter, with a height of 20 metres and weighing 420 tonnes have been transported from Bell Bay in Northern Tasmania to Newcastle on the east coast of mainland Australia.
Principal contractor was lift and shift company Smithbridge Group Pty Ltd. The cargo was moved for client Stolthaven Australia Pty Ltd.
Before the move began the tanks were located at the site of the decommissioned Hydro Tasmania Bell Bay Power Station. To be able to relocate the three large tanks structural work had to be carried out on them to ensure they had sufficient strength and rigidity to be moved. This process involved removing all existing pipe work and oil waste by cutting into the tanks. Support beams were added inside the tank floor and a series of vertical tensioned steel tendons were added so the tanks could safely be moved. Melbourne-based Constructioneering was engaged as proof engineer for structural issues.
The tanks were then individually jacked up in the air to allow a customised transport frame and trailer system to be placed beneath them. Holmatro air bags were used for the lifting procedure. A jacking height of 3.5 m was required to provide enough clearance for the transport frame and trailers. The tanks were supported on braced support stools during lifting. A 3.5 m travel height would allow the tank shell to maintain clearance from sea swell during travel.
The custom transport frame was assembled from Bailey trusses running between fabricated headstocks supporting laterally across the tank. The frame was supported by two side‐by‐side trailer sets, with each set comprising a five axle self‐propelled trailer built by Smithbridge and a six axle Nicolas steerable trailer. The transport frame was designed in‐house by Smithbridge engineers. A jacking height of 3.5 m was required to provide sufficient clearance for the transport frame and trailers.
A customised temporary jetty with the capacity to support the self‐propelled trailer systems and the tank weight was required at Bell Bay to facilitate loading the tanks onto a barge for transport. Separate, parallel 48 m jetties were also built for each trailer. The height of the load on transporters meant that the tanks cleared the safety rails on the bridges and could manoeuvre without impact to the structure. Smithbridge used a 150 tonne capacity Kobelco crawler crane and a 50 tonne capacity Grove rough terrain crane for the jetty construction, along with a launching frame system, which acted as pile leader at each location.
The 579 nautical mile ocean journey from Bell Bay to Newcastle was undertaken using a 76 x 24 m dumb barge, towed by a 40 m tug with a 51 tonne bollard pull. Separate journeys were made for each tank, and local tugs were used for positioning the barge for loading and unloading.
During transportation, the shell of each tank was rested on pedestals welded to the deck. They were not fixed to the pedestals to allow the tanks to adapt to the flexing of the sea journey. This was achieved using support bollards that were installed once the tank was in place.
Once on the pedestals the suspension of the trailers was lowered to remove the load from the transport frame and trailers.
Engineered stops were put in place on the deck of the dumb barge to ensure that the trailers did not move during the sea journey.
All marine engineering work and tow plans were undertaken by International Maritime Consultants Pty Ltd (IMC), Perth. An independent surveyor reviewed the vessel prior to each journey.
Once at Newcastle the barge was positioned end‐on to a container wharf. Unloading could only take place at high tide and water ballasts were used to tilt the deck of the barge to align it with the wharf. In addition, kerbs were removed from the existing wharf to facilitate a smooth transition area for roll-on, roll-off unloading.
Four six‐inch (150 mm) pumps were used to provide a sufficient flow of water between the ballast tanks as the unloading proceeded. The pumps also safely maintained the alignment with the wharf as the weight on the barge shifted and then reduced.
Once the trailers were safely on the wharf apron area, the self‐propelled trailer system carried the tanks over a 1,500 m journey to the final location at the Mayfield Terminal. The trailer systems were then reloaded on the barge for the return journey back to Northern Tasmania on the next high tide.
A combination of reduced preparation work and IMC’s lashing methods meant that barge achieved turnaround times of 50 to 58 hours in both Newcastle and Bell Bay.