ArcelorMittal South Africa New Castle Works

Design, Supply and Installation of a waste gas flue for Blast Furnace N5.

Because of the bad condition of the existing underground waste gas flue AMSA decided to install a new waste gas flue. Repairing of the existing flue would take approximately 2 months during which period the furnace had to be shut down. This was unacceptable. AMSA therefore issued an enquiry to design, supply and installation of a new above ground flue to be installed over the existing one wiht the furnace in operation.
An order was issued to HeatTeQ in April 2011. A site visit was made in May 2011 to inspect the site and to make a survey of the existing system after which design started. HeatTeQ developed a concept whereby the new flue was supported on trestles straddling the existing underground flue. The trestles were supported on one side on piles driven in beside the old flue and on the other side on the stove foundation.

Facts and Figures

Site: AMSA Newcastle South Africa
Duration: 5 months
Plant: BF N5 Waste Gas Flue
Manhours: 40.000
Design: HeatTeQ
Tonnage: Steel 150 ton, Refractories 450 ton
Execution: July-December 2011
Scope: Design, supply and install new waste gas main


Scope of work

Design was completed by the end of July after which procurement started. Sub-contracts were placed for supply and installation of civil, mechanical and refractories. HeatTeQ South Africa performed overall project management with specialized assistance from HeatTeQ Netherlands.

Civil work on site started in the middle of August in parallel with mechical fabrication. Mechanical installation started by the end of September.

The contract called for completion of the project by the end of March 2012. Due to a calamity the furnace was shut down in the middle of August for a repair scheduled for a duration of 3 months. AMSA requested HeatTeQ to shorten the duration of the flue project so the new flue could be taken in operation together with the repaired furnace. Thanks to a concerted effort by HeatTeQ and all sub-contractors this request could be met.

The new flue had to be tied in with the existing waste gas chimney above ground. For this purpose an opening had to be cut in the chimney. This opening had to be properly reinforced. The design of the reinforcement was sub-contracted to Ferbeck, a company within the Lizmontagens group specialized in chimney design. Ferbeck designed the reinforcement with the help of a finite element program.