A METHOD OF REDUCING THE THERMAL STRESSES
IN THE LINING OF THE TUYERE BELT
IN A NONFERROUS METALLURGY CONVERTER
V. V. Slovikovskii
Translated from Novye Ogneupory, No. 5, pp. 44 – 47, May, 2008.
Original article submitted April 2, 2007.
Research results are given on magnesian box-type components in the tuyere belt of horizontal converters at
Ufalei Nickel Corporation. The purpose has been to eliminate the zoning in them by impregnation with nickel
or copper mattes to relieve thermal stresses during use. Components impregnated with matte show improved
physicomechanical and thermophysical properties. A technology has been developed and tested for
impregnating standard components under conditions found at Ufalei Nickel Corporation.
The shortest working lives in nonferrous metallurgy
occur in the linings of copper-nickel converters, which is due
to the very severe working conditions in the refractory lining
there. The resistance of the converter lining is restricted by
the working life in the tuyere zone, which has three
subzones: the tuyere zone proper, the subzone above it
(7 – 12 rows) and the subzone below it (1 – 2 rows). All the
subzones are traditionally lined with periclase-chromide
refractories of the grades PKhS-5, PKhS-17, and PKhS-19.
This low stability is due to features of the matte conver
sion. The resistance is considerably influenced by liquid
impregnating the surface of the lining adjoining the working
space. The thickness of the impregnation sometimes attains
100 – 150 mm. The resulting liquid-refractory system be
comes more sensitive than the original refractory material
because of the matte. A factor influencing the resistance is
the cleavage of the refractory, which occurs when the
temperature fluctuates on handling the slag-matte liquid.
This handling gives rise to thermal stresses in the refractory.
The cracks occur mainly at the boundary of the impregnation
with slag-matte liquid in the least altered zone of the
refractory, which is parallel to the working surface.
To analyze the stresses and strains in the individual zones
during use and at the boundaries between them, we examine
the elastic modulus, thermal expansion coefficient (TEC)
and compressive strength of various types of refractory
component most widely used in converter tuyere zones .
Table 1 gives the elastic modulus at 20°C for standard
magnesian refractories, and also mattes in the refractory-
matte systems. Impregnating the refractories with mattes
increases the elastic modulus.
To determine the relative elongation å of standard
refractories of magnesian composition, grades M, MPM,
PKhS, KhM, KhPT, and PKhPPP we made three batches of
specimens of size 40´5 mm, one of which was impregnated
with nickel matte from Ufalei Nickel Corporation, the
second with copper matte from the Middle Ural copper-
melting plant, and the third for determination of the TEC of
the initial refractories (before impregnation). The composi
tion of the mattes used for impregnation in wt.% were as
follows: Ni matte 17.6 Ni, 53.0 Fe, and 28.5 S; Cu matte 34.6
Cu, 30.5 Fe, and 25.6 S. Table 2 gives the results, which
show that the TEC of the initial and impregnated refractories
differ considerably. These differences also occur in the
compressive strength (Table 3).
Refractories and Industrial Ceramics Vol. 49, No. 3, 2008
1083-4877/08/4903-0216 © 2008 Springer Science+Business Media, Inc.
OUVPO Urals State Technical University – Urals Polytechnical
TABLE 1. Magnesian Refractory Elastic Moduli E
MPa Material E,10
Matte: KhM–Cu matte 63.6
copper 32.0 KhM (initial) 45.3
nickel 15.2 KhPT (initial) 14.6
PMP (initial) 46.2 KhPT–Cu matte 49.4
PMP–Cu matte 86.0 KhPT–Ni matte 45.7
PMP–Ni matte 60.7 M (initial) 89.6
PKhS (initial) 12.5 PKhPPP (initial) 11.4
PKhS–Ni matte 62.4 PKhPPP–Cu matte 48.4
KhM (initial) 19.3 PKhPPP–Ni matte 53.3