November will see completion of a tricky two year concept development and design programme to install a blast furnace in Taiwan for the China Steel Corporation.
The new plant has been designed by Paul Wurth of Luxembourg in close co-operation with turnkey contractor Dorman Long, which has had to address the challenge of installing the furnace into an existing housing.
All eight sections of the blast furnace have been fabricated on site by China Steel. The structure has an overall height of 40m, with the heaviest section weighing 477t. Total weight on completion will be 3,044t.
Sections have to be inserted into and stacked within the superstructure's existing steel cage.
The installation programme must last no longer than 20 days to avoid penalty clauses.
To achieve this, Dorman Long's team of nine UK engineers and 16 locally-sourced erectors will work around the clock in programmed two hour shifts.
There is no room in the furnace building for large cranes and each of the new components must be delivered to the furnace support frame from the access point 95m away. To add complexity, components have to be inserted into the support frame some 13m above ground level. Dorman Long has designed a 95m long skid track supported on six steel towers. A climbing jack tower system will lift components.
To minimise friction the skid track beams will be faced in stainless steel and coated with PTFE. Dorman Long plans to use four 1m stroke, 35t hydraulic rams to move the furnace units into their housing. Each unit will take six hours to move into position.
At the top of the furnace housing Dorman Long will install a ring of eight 418t strand jacks, while a further ring of eight 185t strand jacks will be set up just above mid-height. After the first two blast furnace components have been installed, welded and positioned at the base of the housing, the upper six sections will be skidded in. The topmost unit will be installed first, with other units stacked beneath it. All eight 418t jacks will be lowered and connected to the top section to raise it out of the way of the following section.
Once the sections have been welded together, the procedure will be repeated. Finally the combined upper sections will be lowered onto the base sections for welding.