Ladle brick leveling set

A ladle brick leveling set for high temperature molten metal ladles in which specially shaped refractory bricks are disposed in a slightly sloping geometrical configuration so as to compensate for a sloping bottom of a high temperature molten metal ladle. The bricks are disposed in two partial rings each of which is essentially a mirror image of the other so that the height of the leveling set varies substantially uniformly from a high point where the two mirror image portions join to a low point 180 degrees of arc displaced therefrom where the two portions again join. Each of the refractory bricks has a slight taper in height so that the ends of each brick are the same height as the juxtaposed ends of the adjoining bricks.

This invention relates to high temperature refractories and more 
particularly to courses of refractories providing for leveling of 
refractories in vessels with sloping bottoms. 
BACKGROUND OF THE INVENTION 
As will be recognized by those skilled in the art, in high temperature 
vessels such as molten steel ladles, one problem heretofore encountered 
relates to preventing slag from contaminating or otherwise being mixed 
with the relatively pure steel when it is being withdrawn from the vessel. 
Since slag is less dense than the molten steel, the slag tends to rise and 
accumulate on top of the underlying steel. If a pouring orifice is 
provided in the bottom of the vessel, relatively uncontaminated molten 
steel can be withdrawn simply by opening the orifice to permit the liquid 
steel to exit therethrough. However, when the liquid surface falls until 
it is near the bottom of the vessel, pouring must stop before slag exits 
along with the remaining steel; and thus a small quantity of steel remains 
in the vessel and is unusable. In order to keep this quantity as small as 
practicable, it has become customary to provide sloping bottoms with a low 
point at or near the edge of the vessel where a pouring orifice is 
positioned. However, this has brought about a relative inefficiency in 
refractory brick utilization. 
The harsh and erosive properties of slag are well known; and in order to 
protect walls of a vessel in the vicinity of slag locations a refractory 
brick that is more slag-resistant (and more expensive) than refractory 
bricks for contact with molten steel has been required. Thus, less 
expensive refractory bricks that are acceptable for use in contact with 
molten steel do not adequately withstand the rigors of on-going contact 
with slag. Accordingly, it has been customary to line the interior of a 
vessel designed for use with molten steel (e.g., a ladle) with lesser cost 
refractory bricks in regions encountering just liquid steel, while 
installing the more costly bricks only in regions expected to normally 
encounter slag. Since slag normally resides on the surface of the molten 
steel, such more costly bricks are used to line just the upper region of 
the interior which usually is adjacent the mouth of the vessel. 
For simplicity and cost effectiveness, it is customary to line the interior 
of a high temperature vessel with refractory bricks beginning at the 
bottom; and, after installing bricks overlying the bottom, to work upward 
to cover the interior walls with successive courses until the entire 
interior has been covered. It will thus be observed that if the bottom 
slopes, the successive rings of side wall bricks will also slope, forming 
rings that are tilted to follow the slope of the bottom. However, the 
surface of the liquid contents of the vessel will be horizontal, generally 
parallel to the plane containing the earth's natural surface at that 
location; and so the plane containing the liquid surface will lie at an 
angle to the planes of the successive rings of refractories. Accordingly, 
in order to ensure that normal contact between slag and refractories is in 
a region of the lining in which the more expensive bricks are installed, 
it has been necessary to provide several extra courses of such more 
expensive bricks. 
The use of refractory castables or ramming mixes to compensate for the 
slope is generally unsatisfactory. Monolithic materials, field applied, 
never develop the desirable combination of physical and chemical 
properties typical of a fired brick. Cast or rammed fillers or ramps 
require extended and, hence, costly installation time. 
BRIEF SUMMARY OF THE INVENTION 
The improvement according to the invention hereof includes the provision of 
one or more courses of bricks of coordinated and tapered heights to form 
correspondingly tapered compensating courses. In vessels of essentially 
circular or oval geometry, this results in the provision of an essentially 
circular ring which from a high point (where the bricks of the ring are 
the highest, tapers to a low point 180 degrees displaced therefrom where 
the bricks of the ring are the lowest. Thus, the taper of the ring or 
rings compensates for the sloping bottom so that additional courses of 
bricks that are installed above the compensating courses lie in planes 
generally parallel to the surfaces of both liquid metal and slag; and 
since the aforementioned relative angle therebetween is; eliminated, only 
one course (or minimum number of courses) of the more expensive 
slag-resistant bricks are required to encompass expected slag contact 
regions, thus saving cost. 
OBJECTS AND FEATURES OF THE INVENTION 
It is one general object of the invention to improve high temperature 
refractory linings in liquid steel handling vessels. 
It is another object of the invention to facilitate use of such vessels in 
which the bottoms are sloped. 
It is another object of the invention to reduce maintenance costs for high 
temperature linings for refractory-lined vessels with sloping bottoms. 
It is yet another object of the invention to reduce damage and down time 
for high temperature refractories resulting from slag attack. 
Accordingly, in accordance with one feature of the invention, pluralities 
of individual refractory bricks are assembled to form courses having 
heights that are tapered to compensate for the slope angles of sloping 
bottoms, thus providing support for succeeding courses of refractories 
that are generally parallel to expected layers of erosive materials such 
as slag. 
In accordance with another feature of the invention, the compensating 
course (or courses) may be positioned adjacent the sloping bottom of the 
vessel or part of the way up the sides, thus providing flexibility in 
installation. 
In accordance with another feature of the invention, the aforementioned 
course arrangements may be installed in annular rings each of which, for 
circular vessels, may be configured in two 180 degree semicircles which 
are mirror images of each other, thus enhancing simplicity of installation 
.

DESCRIPTION OF A PREFERRED EMBODIMENT 
Now turning to the drawing, and more particularly FIG. 1 thereof, it will 
be seen to depict a typical circular vessel or ladle 10 employed in the 
steel-making industry for handling molten steel. The vessel typically 
includes an outer steel shell 11, a first lining of refractory bricks 12, 
and an interior lining of refractory bricks 13. Included within the 
interior bottom are conventional tap hole 14, and injector locations 15 
and 16. Injectors are not necessarily employed in all ladles, and the tap 
hole is preferably located at the lowest point of the sloped bottom. The 
offset shown in FIG. 1 is to accommodate other equipment. 
To further illustrate the interior of FIG. 1 and to depict the leveling 
courses of refractories constructed according to the invention, sections 
2--2 and 3--3 are shown respectively in FIGS. 2 and 3. In FIG. 2, there 
are seen two layers 17 and 18 of refractories that typically line the 
bottoms of high temperature liquid steel handling vessels. It will be 
observed that these two layers are each generally of uniform thickness and 
are installed to present a sloping upper surface 19 which slopes down 
toward tap hole 14 so as to facilitate draining of molten steel from the 
vessel. As mentioned above, such sloping surface provides advantages. 
However, in order to provide the aforementioned levelling, a pair of 
tapered layers 20 and 21 are installed so that the upper surface 22 of 
layer 21 is essentially level (as shown). Accordingly, successive courses 
of bricks as represented by courses 23 and 24 are essentially parallel to 
the plane containing the mouth (not shown) of the vessel 10 so that the 
course of the more slag-resistant (and expensive) refractories described 
above need be of minimum height. If the dimensions of the ladle are such 
that the ends of the tapered layers 20 and 21 are not adjoining, they can 
be made to "communicate", i.e., form a ring with the use of transition 
refractories. At both ends of tapered layers 20 and 21 there are shown 
transition refractories 25a/25b and 26a/26b which connect with the layers 
and abut conventional side wall refractories 27 and 28. Refractories 
25a/25b and 26a/26b are splits or soaps which are not tapered and are of 
the same thickness (height) of the adjacent brick in the ring. 
FIG. 3 is seen to depict the geometrical relationship of the foregoing 
courses of refractories at an angle of 90 degrees to that of FIG. 2; and 
like parts are, of course, identified with like symbols. There, the 
levelling courses 20 and 21 are are shown, with surface 22 of layer 21 
being essentially level, and with the line 29 between layers 20 and 21 
reflecting the tapering and curved nature of the interior of the vessel. 
Now turning to FIGS. 4 and 5, a refractory brick according to the invention 
hereof is depicted. FIG. 4 is a top view of a particular semi-universal 
brick 30, that along with a universal brick is preferred for practicing 
the invention. Also suitable are key, circle, wedge brick, and the like. 
There, it will be observed that brick 30 includes a pair of substantially 
parallel surfaces 31 and 32, together with a pair of curved surfaces 33 
and 34 which are complementary and provide for form fitting of adjacent 
bricks as is shown in FIG. 6. 
As mentioned above, FIG. 5 is a side view of the special brick of FIG. 4 
and illustrates the gradual tapering feature that results in compensation 
as previously described. Thus, the height of the brick at end 33 as 
measured by dimension 35 is greater than the height of the brick at end 34 
as measured by dimension 36; and the difference, as represented by 
dimension 37, results in a controlled taper in brick height which is 
progressive as shown in FIG. 6. Thus, height of each brick in the 
representative half circle ring of FIG. 6 is different from each adjacent 
brick so as to result in a smooth taper from left end 40 to right end 41 
as shown. Also, it should be observed that at right end 41, the much less 
high (shorter) refractories are shown and their relevant surfaces are 
identified by numerals 32a and 34a. 
It will be evident that in order for compensation (as described above) to 
occur, the amount of taper is determined by the degree to which the bottom 
refractories 17 of the vessel 10 slope as evidenced by the slope of 
surface 19 (FIG. 2). Therefore, the amount of taper from left end 40 to 
right end 41 will vary depending upon the taper of the bottom slope of the 
vessel. 
As mentioned above, FIG. 6 is a perspective view illustrating one of two 
semicircular half rings of refractory bricks configured according to the 
invention, the complementary semicircular half ring being a mirror image 
of the half ring shown. In FIG. 6 it will be observed, there are two 
essentially identical courses of refractories, one overlying the other. To 
complete a full ring, the mirror image courses are adjoined at ends 40 and 
41 to complete a circular installation as depicted in FIGS. 1-3. 
To join two half rings, "left" and "right" hand tapered brick would be 
required. To avoid additional mold costs, a more practical approach is to 
cut the ends of both courses of both rings so that they mate at a plane 
vertical surface. 
FIG. 7 is a side view depicting a modification of FIG. 6 in which two 
courses of bricks overlie one another for the principal part of the 
semicircle, while the thinner end is comprised of a single layer only. 
Thus at left end 42 the overlying nature of the courses is represented by 
overlying refractories 30a and 30b which in one illustrative embodiment 
result in a total course height at end 42 of 8.5 inches as shown by 
dimension 43. In this embodiment, the dual geometry of the courses 
continues to point 44 at which the total height has declined such that the 
remainder includes just one brick 45. In the illustration hereof, the 
height at end 46 has decreased to 1.25 inches as shown by dimension 47. 
As mentioned above, the principles of the invention may have applicability 
to non-circular vessels; and to illustrate such, there is included the 
array shown in FIG. 8. There, in FIG. 8 is depicted a top view 
illustrating tapered refractories of the general type shown in FIG. 4. 
Beginning at the left end 49 of the array are courses 50-50d which 
continue to right end 51 which concludes with course 50cc. As with the 
configurations previously described, the degree of taper provided by 
refractories 50-50cc is complementary to the corresponding slope of the 
lower surface of the vessel in which they are to be installed so as to 
provide levelling compensation. Thus the principle can be applied to 
linings comprising both curved and plane surfaces. 
It will now be evident that there have been described herein improved 
leveling assemblies and refractory bricks for use therein. 
Although the inventions hereof have been described by way of a preferred 
embodiment, it will be evident that other adaptations and modifications 
may be employed without departing from the spirit and scope thereof. 
The terms and expressions employed herein have been used as terms of 
description and not of limitation; and thus, there is no intent of 
excluding equivalents, but on the contrary it is intended to cover any and 
all equivalents that may be employed without departing from the spirit and 
scope of the invention.