To
further strengthen our basic industries that will take part
in building a stronger Saudi Arabia. Al-Tuwairqi Group (ATTC)
has launched a new project of steel melt shop by the name
of National Iron and Steel Factory (NSIF), which will prove
to be a new feather in the Hat of ATTC.
About
one-quarter of the world’s steel is produced by the electric-arc
method, which uses high-current electric arcs to melt
steel scrap and convert it into liquid steel of a specified
chemical composition and temperature. External arc heating
permits better thermal control than does the basic oxygen
process, in which heating is accomplished by the exothermic
oxidation of elements contained in the charge. This allows
larger alloy additions to be made than are possible in
basic oxygen steel making. However, electric arc steel making is not as oxidizing,
and slag-metal mixing is not as intense;
therefore, electric-arc
steels normally have carbon contents higher than 0.05
percent.
In
addition, they usually have a higher nitrogen content
of 40 to 120 parts per million, compared with 30 to 50
parts per million in basic-oxygen steels. Nitrogen, which
renders steel brittle, is absorbed by liquid steel from
air in the high-temperature zone of the arc. The nitrogen
content can be lowered by blowing other gases into the
furnace, by heating with a short arc, and by applying
a vigorous carbon monoxide boil or argon stir to the melt.
The
big venture will produce 300,000 ton billet per annum
in the first phase which will go up to 500,000 ton per
annum by the end of second phase. It will produce 120
x 120 mm; 130 x 130 mm and 150 x 150 mm billet size.
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