EXPERIENCE OF THE MANUFACTURE AND OPERATION
BLOWING PLUGS (LANCES) PRODUCED BY OOO KERALIT
I. V. Egorov
and A. S. Matvienko
Translated from Novye Ogneupory, No. 11 pp. 23 – 26, November 2009.
Original article submitted September 21, 2009.
One way of improving metal quality is bottom blowing with inert gas in a steel-pouring ladle through a blow-
ing plug with treatment in a furnace-ladle unit and in an evacuator. Information is provided about experience
of producing and operating OOO Keralit blowing plugs (lances).
Keywords: blowing plug (lance), OOO Keralit, nesting block, safety indicator, extra-furnace steel treatment.
Development of contemporary steel smelting production
requires improvement of methods for smelting and extra-fur-
nace steel treatment technology in order to prepare high
quality steels. Extra-furnace steel treatment is an important
link in the production chain for preparing steel in the section
between the steel smelting unit and steel pouring. Currently
ladle metallurgy makes it possible:
– to increase the productivity of a steel smelting unit as
a result of increasing the rate of chemical processes during
extra-furnace steel treatment;
– to accomplish fine steel finishing with respect to
– to improve steel cleanliness with respect to non-metal-
– to accomplish metal degassing;
– to prepare a melt for subsequent pouring by regulation
of the casting temperature and casting properties;
– to coordinate with respect to time the work of steel
smelting units and the pouring section.
Most widespread is the process of blowing metal in a la-
dle with inert gas with correction of steel composition and its
temperature. The requirement for this process from the time
of its appearance in the 1950 – 60s is explained mainly by
the fact that the continuous steel casting method developed at
that time required clear regulation of metal temperature in
the ladle and uniformity of its chemical composition .
An inert gas, passing in stirred metal, may be introduced
into the metal through a plug installed in the bottom of the la-
dle, or introduced into the metal from above . According
to representatives of one metallurgical plant, as a result of us
ing bottom blowing plugs assimilation of manganese by the
metal increased compared with the technology without bot-
tom blowing by 19%, silicon by 12%, and aluminum by
9.5%. In order to achieve 95% metal homogenization
6 – 8 min of bottom blowing is sufficient. In melts with up-
per blowing this time varies from 12 to 14 min .
Thus, the most effective technology for resolving the
task of ladle metallurgy is bottom blowing of the metal with
an inert gas through blowing plugs, that operate under severe
conditions of abrasive action of heated molten metal, chemi-
cal erosion of slag of variable composition, and thermal
shock that arises during metal pouring . In order to pro-
vide high stability during operation blowing plugs should ex-
hibit low open porosity, high mechanical strength and ther-
mal shock resistance, be stable towards the chemical action
of molten metal and slag. Plug construction should provide
constant gas flow rate at a prescribed pressure, controlled
plug wear during operation, and the possibility of normal ser-
vice and as necessary its replacement.
Since 2005 OOO Keralit has been concerned with devel-
oping the construction of blowing plugs, and production
technology of refractory material for their manufacture. At
the start of assimilation into production in the Keralit com-
pany plant the construction and manufacturing technology of
blowing plugs has steadily improved. Particular attention is
devoted to reliable blowing plug operation. Taking account
of experience of operating domestic and imported analogs
rational structural solutions for blowing devices have been
The operating features in each metallurgical enterprise
are taken into account in planning blowing plugs. In prepar
ing plugs it is correct to use expensive low-cement and
Refractories and Industrial Ceramics Vol. 50, No. 6, 2009
1083-4877/09/5006-0415 © 2009 Springer Science+Business Media, Inc.
OOO Keralit, Moscow, Russia.