REFRACTORIES IN HEATING UNITS
REFRACTORIES FOR METAL BLOWING WITH ARGON
IN OAO MMK STEEL-POURING LADLES
E. V. Burmistrova
and R. I. Abdrakhmanov
Translated from Novye Ogneupory,No.7,pp.5–9,July 2014.
Original article submitted April 9, 2014.
Information is provided about forms of refractory objects used for metal blowing in steel-pouring ladles, their
operating principles, and results obtained. On the basis of comparative analysis the most effective technology
is recognized for blowing steel with argon in the bottom of a steel-pouring ladle through a bottom plug. Corre
sponding to this, bottom blowing under OAO MMK conditions uses objects highly recommended for testing
with formation of radially arranged working channels.
Keywords: blowing with argon, steel-pouring ladle, slotted channels, blowing blocks.
Production of high quality steel requires assimilation of
new technology and improvement of equipment construction
used for all stages of a production process. An important fac-
tor is choice of materials capable of withstanding action of
metal and slag for a long time at high temperature, and also
objects made from them providing reliability during opera-
In the last decade in ferrous metallurgy there has been a
steady trend to ladle treatment of steel.
Blowing metal with argon is an important link in tech
nology for preparing high quality steel. The main purpose of
blowing with inert gas is optimizing metal temperature and
chemical composition, and removal of dissolved gases and
nonmetallic inclusions. The main stage in using bottom
blowing is extra-furnace steel refining carried out in steel ex
tra-furnace treatment units. The main proportion of metal
finishing under conditions of the oxygen converter workshop
(OCW) of OAO MMK is in fact performed in steel extra-fur
nace treatment (SET) units such as FFU, MFU, SEPU, and
SBU. The semifinished product obtained after delivery from
a converter requires quite prolonged and labor-consuming
processes, and mainly it is converted into steel suitable for fi
nal pouring. The main production processes facilitating
achievement of the required cleanliness and conformity of
metal quality are the possibility of additional electric heating
in a ladle furnace unit (LFU), and also blowing molten steel
in a steel-pouring ladle with inert gas.
Before 2000 metal finishing was carried out in the OCW
in steel finishing units (SFU) and a steel equalizing prepara
tion units (SEPU). Additional metal heating was accom
plished by chemical heating and induced metal mixing and
cleaning from nonmetallic inclusions by means of blowing
argon through top lances. The proportion of degassed metal
in the period indicated did not exceed 5% of the overall out
put volume. However, with further development of produc
tion these finishing methods could not provide the metal
quality required. The problem consisted of a lack of the pos
sibility of fine control of the volume of inert gas supplied
since gas bubbles forming with top blowing had too large a
size (according to the diameter of the lance working nozzles)
and could not clean metal effectively from nonmetallic and
gas inclusions. Metal top blowing technology with argon was
initially considered to be use of a lance with a refractory
layer, made from individual aluminosilicate components.
The efficiency of these lances was low both with respect to
operating and the degree of metal equalizing and cleanliness.
Due to development and introduction of poured concrete
lances it appeared possible to improve steel finishing effi
ciency due to a structural solution for the technology of ar
gon supply to a melt.
Refractories and Industrial Ceramics Vol. 55, No. 4, November, 2014
1083-4877/14/05504-0267 © 2014 Springer Science+Business Media New York
From proceedings of the International Conference of Refractory
Workers and Metallurgists (4 – 5 April 2014, Moscow).
OAO Magnitogorsk Metallurgical Combine (MMK), Magnito