BlueScope Steel approached SOTO Consulting Engineers in early 2018 to provide structural and mechanical engineering design services for a new slab pre-heat oven. The two firms went on to form a collaborative BSL-SOTO project team to deliver a pre-heat oven design that was thorough in its engineering and robust in its function in the steel plate-making process.
BlueScope Steel (BSL) produces high quality rolled steel plates at its Port Kembla Steelworks Plate Mill. Approaching half-a-century since the first plates rolled out, this facility remains the sole wide plate mill in Australia.
BlueScope steel slabs are reheated at the Plate Mill in a 1,200 degrees Celsius pre-heat furnace using heat recuperated from other steelmaking processes for improved energy efficiency. From this pre-heat oven, each slab goes through a sophisticated plate rolling process that includes removal of scale from the surface of the slab and obtaining the required width and thickness of the slab ahead of plate-making.
With specific requirements, the pre-heat is to do with the Australian Defence Submarine project and the production of specialised steel plate for the proposed new fleet of submarines. The preheating process will ensure that the quality of the finished rolled plate meets the strict quality and metallurgical composition for the intended submarine construction.
As part of the initial scope, the BSL-SOTO team was required to come up with concepts for a retractable roof for the pre-heat oven. The roof design needed to accommodate overhead cranes equipped with tongs to move the steel slabs in and out of the oven. Roof concepts that had demonstrably succeeded elsewhere were an integral part of this design process. The thermal, structural integrity of the roof, as well as its ability to be operated remotely and its overall reliability, were critical to the project.
Because of the size of the crane tongs and the slab itself, the concept engineering needed to thoroughly review how the roof tongs would operate within the confines of the oven while minimising/obviating the risk of any damaging impact on the structure. A similar assessment was also needed to make the structure resilient against slab impact. The team would also closely look at minimising the temperature of all sides of the oven structure by optimising its thermal insulation.
As the roof was to be retractable, the team was also required to review various options for systems to open and close the roof as needed.
Like every step in the concept engineering process, the team needed to operate under the overarching criterion of risk minimisation.
The conceptual project design enabled an effective structural and mechanical solution to evolve, while the hazards of operating the slab lifting tongs efficiently are addressed in a separate study.
SOTO Consulting Engineers are proud to be associated closely with a project of such standout importance in Australian steelmaking and its connection with the Australian Defence Submarine project.
With specific requirements, the pre-heat is to do with the Australian Defence Submarine project and the production of specialised steel plate for the proposed new fleet of submarines.