GB2048443A

GB2048443A - Refractory brick for lining a metallurgical container

Info

Publication number: GB2048443A
Application number: GB8013436A
Authority: GB
Original assignee: Cockerill SA
Current assignee: Cockerill SA
Priority date: 1979-04-24
Filing date: 1980-04-23
Publication date: 1980-12-10
Also published as: BR8002485A; ES259704U; IT8021609A0; ES259704Y; AT380565B; DE3015331C2; SE8003074L; JPS55146383A; SU1056882A3; NL8002361A; IT1141317B; FR2455259B1; GB2048443B; ATA217480A; DE3015331A1; SE440143B; CH644658A5; LU82395A1; FR2455259A1

Abstract

The brick has a plane upper surface (2) and a plane lower face (3) parallel and identical to the upper face. The inner face (4) is square or rectangular and the outer face (5) is also square or rectangular and has a width greater than that of the inner face (4). Two non- parallel lateral faces (6, 7) join the inner and outer faces. The inner face is offset with respect to the straight line passing through the centre (9) of the outer face and extending perpendicular to the outer face. In other embodiments the lateral faces may be curved. <IMAGE>

Description

SPECIFICATION Refractory brick for lining a metallurgical container The present invention relates to a refracting brick having a shape which is specially designed for the construction of refractory linings of metallurgical containers.

Such a brick is constituted substantially by a block of refractory material. This block is defined by an upper face, a lower face, an inner face, an outer face, and two opposite lateral faces. The upper and lower faces are plane, parallel, and identical. The inner and outer faces are square or rectangular, but differ in that the outer face has a greater width than that of the inner face, although it is of the same height. The lateral faces are not parallel to one another.

During laying of the refractory lining, the inner face of a brick is positioned to face towards the axis of the container, whereas the outer face is towards the shell of the container.

Known bricks of this type used at present for the above-mentioned laying of the lining are refractory blocks in the shape of right prisms having isosceles trapezium shaped bases. In other words, the upper and lower faces have the shape of identical isosceles trapeziums, disposed plumb with one another and both centered on a same straight line which is perpendicular to them. The inner face is therefore positioned symmetrically when respect to the outer face.

The laying of the refractory lining may be carried out in accordance with the technique of successive superposed rows which are independent of one another and disposed respectively along peripheries centered on the axis of the metal shell, or in accordance with the technique of rows disposed along a helix whose axis is coincident with that of the metal shell. The helical arrangement of the rows of bricks is often preferred as, in contrast with the first technique, it enables the avoidance of the need to use closure bricks which are cut to size and which are used to end the various rows and the avoidance of the use of bricks having varying taper in order to compensate for the variations in the dimensions of the metal shell and the variations in the dimensions of the bricks resulting from pressing during their manufacture.

By way of example, Tables I and II give a summary of the number and diversity of format of known bricks having a thickness of 100 mm and designed for use in the lining of metal shells in accordance with the first technique described above (superposed, successive, independent rows).

In the case of the second technique mentioned above (rows which are superposed but arranged helically), the bricks generally used have both lateral faces curved in the same direction. In this way, it is possible, in accordance with the laying requirements, to juxtapose the bricks relative to one another in order to come closer to or move away from the metal shell without requiring systematic changes of brick to take into account variations of the key of the bricks, i.e. the differences between the widths of the outer and inner faces of the bricks. Despite this advantage presented by the second technique, the known juxtaposed bricks have a considerable disadvantage in particular when the laying of refractory linings in mechanised.In effect, as soon as the bricklaying rate is increased, the operator is no longer able to react quickly enough to make an accurate correction at the required time of the variations of key appearing relative to the ideal plan of bricklaying. Consequently the bricklaying work is slowed down and causes, in the case of the operator on the work-table, such an accumulation of bricks that the progesss of bricklaying is completely disorganized. Therefore, the saving of time during bricklaying desired as a result of accelerating the rate of laying of the bricks is then almost completely lost.

The invention relates to a refractory brick enabling the above-mentioned drawback of the technique of bricklaying with juxtaposed bricks to be remedied. The brick enables any inadvertent variations in curvature appearing in the row being laid to be very rapidly compensated. It is important to note that the brick may be advantageously applied to the abovementioned bricklaying techniques, whether conventional manual brick-laying (first technique) or accelerated mechanised bricklaying (second technique).

For this purpose, according to the invention, the centre of the inner face of the brick is offset, parallel to the upper and lower surfaces, with respect to the straight line passing through the centre of the outer face and extending perpendicular to the latter.

As a result of the features of the shape of the brick it is possible, by placing one of the bricks in an inverted position in the row, to correct any abnormal curvature appearing in this row very rapidly, without the inverted brick falling from the row under its own weight into the container during tilting of the container.

In addition, the features of the shape of the brick provide a considerable reduction in number and diversity of format both in the first bricklaying technique having rows aligned along the peripheries and in the second technique having rows aligned helically in which the tendency towards simplification has already been started.

Furthermore, there are already is existence certain bricks whose small lateral faces are curved along suitable lines of curvature (but whose inner and outer faces are not offset with respect to one another). In certain cases, these minor lateral faces are even ribbed or toothed in such a way that the bricks retain each other and do not slip with respect to one another during tilting of the metallurgical container. However, the ribs and teeth of the minor faces in question makes their dry juxtaposition very difficult, which is not acceptable in the case of mechanised bricklaying.

In order to ensure the mutual maintenance of the bricks, the above-mentioned notion of the curvature of the lateral faces may again be used in bricks according to the present invention.

The lateral faces of the brick may thus be curved in the same direction and with the same- radius of curvature.

In addition, in order to prevent chipping of the edges of the brick at acute angles between its lateral surfaces and its inner and outer surfaces, these edges are advantageously bevelled over their entire height, and the acute angles may become substantially right-angled.

In order to avoid sharp edges subject to chipping and also in order ta facilitate the mutual juxtaposition of the bricks, their lateral faces may be doubly curved in the shape of an S which is symmetrical with respect to its centre. The curvature of these lateral faces is in the same direction and with the same radii of curvature.

It should be noted that the inventive concept may be advantageously applied to bricks whose lateral faces are right-angled, plane, and non-articulated. In addition, this inventive concept also enables penetration of the liquid metal and the slag into the joints between the bricks in the rows to be prevented, as these joints are not aligned in radial directions of the metal shell but are inclined in a rectilinear or curvilinear manner.

The invention also relates to a refractory lining for a metallurgical container. The refractory lining is constituted by rows of superposed bricks, about the axis of the metal shell of the metallurgical container. In each row of the new refractory lining, the bricks are inclined about their geometric centre with respect to the radial direction of the metal shell passing through this centre. In addition, the relative position of the bricks in the row may be corrected by sliding along their lateral surfaces in such way that their outer surfaces follow the metal shell without gaps, whilst their internal surfaces form the inner profile of the lining without gaps. In this way, the lining, as it progresses, acquires a given curvature which follows that of the ideal bricklaying plan accurately.

The invention will be described further, by way of example, with reference to the accompanying drawings, in which: Figure 1 is a perspective view of a first embodiment of a refractory brick; Figure 2 is a plan view of the first embodiment; Figure 3 is a perspective view of a second embodiment; Figure 4 is a plan view of the second embodiment; Figure 5 is a perspective view of a third embodiment; Figure 6 is a plan view of the third embodiment; Figure 7 is a perspective view of a fourth embodiment, having bevelled acute edges; Figure 8 is a plan view of the fourth embodiment; Figure 9 is a perspective view of a fifth embodiment; Figure 10 is a plan view of the fifth embodiment; Figure 11 is a perspective view of several superposed rows of bricks of the fifth embodiment, forming part of the refractory lining of a metallurgical container; and Figure 12 is a perspective view of three adjacent bricks in a row, illustrating the compensation of taper by inversion of the position of the middle brick.

Each 1 brick illustrated is of refractory material and is defined by an upper face 2, a lower face 3, an inner face 4, an outer face 5, and two opposite lateral faces 6 and 7. The upper face 2 and the lower face 3 are plane, parallel, and identical. The inner face 4 and the outer face 5 are plane, square or rectangular, and (for example) parallel. The faces 4 and 5 have the same height, but the inner face 4 is not as wide as the outer face 5. The lateral faces 6 and 7 are not parallel to one another.

The inventive concept applied to the refractory bricks consists of offsetting the inner face 4 with respect to the outer face 5, parallel to the upper and lower faces 2 and 3. In other words, the centre 8 of the inner face 4 is offset (strongly or not) from the perpendicular line from the centre 9 of the outer face 5. Thus, a straight line 10 passing through the centres 8 and 9 is oblique with respect to the planes of the inner and outer faces 4 and 5, instead of being perpendicular to these planes.

In the first embodiment (Figs. 1 and 2), the upper face 2 and the lower face 3 are identical scalene trapeziums; the sides joining their parallel bases are straight edges. In addition, the lateral faces 6 and 7 are rectangles of the same height but the face 6 is longer than the face 7.

The inner face 4 is offset towards the left with respect to the outer face 5 parallel to the upper and lower faces 2 and 3. In other words, the centre 8 is on the left of the perpendicular to the centre 9 of the outer face 5 and the straight line 10 is slightly inclined with respect to the perpendicular to the inner and outer faces. 4 and 5. As regards this inclination, it should be noted that the orthogonal projection of the sharp edge of the left of the inner face 4 on the plane of the outer face 5 (as indicated by the broken line in Fig. - 2) is located in this face 5 and at a small distance from its left-hand edge.

In the second embodiment (Figs. 3 and 4), the upper and lower faces 2 and 3 remain plane but are geometric figures each defined by two straight, parallel, unequal segments and two unequal curved segments having, however, the same radius of curvature. Thus, the lateral faces 6 and 7 are curved rectangular figures having different lengths but equal curvatures. The straight line 10 passing through the centres 8 and 9 is again inclined slightly with respect to the perpendicular to the faces 4 and 5, the orthogonal projection of the left-hand edge of the iner face 4 on the plane of the outer face 5 (as indicated by the broken line in Fig. 4) lying outside this face 5 but close to its left-hand edge.

The third embodiment (Figs. 5 and 6) is similar to the first and is only differentiated from it in that the straight line 10 has a greater inclination with respect to the perpendicular to the planes of the faces 4 and 5. The inner face 4 is strongly offset towards the left with respect to the outer face 5. The orthogonal projection of the left-hand edge of the inner face 4 on the plane of the outer face 5 (as indicated by the broken lines in Fig. 6) lies clearly beyond the face 5 and at a large distance from its left-hand edge, this distance being almost equal to its width.

The fourth embodiment (Figs. 7 and 8) is similar to the fourth and is differentiated from it in that the sharp corners of the brick 1 are cut off. In this case, the edge 11 of intersection of the inner face 4 and the lateral face 7 has a bevel 1 2 cutting off its sharp corner, and in the same way the edge 1 3 of intersection of the outer face 5 and the lateral face 6 has a similar bevel 1 4.

Thus, the acute-angled edge 11 between the faces 4 and 7 and the acute-angled edge 1 3 between the faces 5 and 6 are bevelled over their entire height. The bevelling of the edges 11 and 1 3 avoids acute angles, these being very difficult to obtain during pressing of the brick 1.

In the fifth embodiment (Figs. 9 and 10) the upper face 2 and the lower face 3 are again plane but are identical geometric figures each defined by two parallel unequal straight segments and two unequal curved segments each extending in the form of an S symmetrical with respect to its median point, these S-shapes having corresponding curvatures in the same direction and having the same radii of curvature. Each lateral face 6 or 7 is thus a curved rectangular figure which is curved in different directions on either side of the median line parallel to its small sides.

The inclination of the straight line 10 is substantially equal to that in the fourth embodiment.

It should be noted that in each case, the selection of the angle of inclination of the straight line 10 with respect to the planes of the faces 4 and 5 depends in particular on the distance between these faces 4 and 5, on the width of these faces 4 and 5, and on the local curvature of the metal shell against which the brick is to be laid.

During pressing, the brick may be provided with cardboard (not shown) on one lateral face 6 or 7 and/or on its lower face 3. The cardboard is placed on the base and/or on one lateral wall of the mould for producing the bricks before the refractory material is poured in. The cardboard enables the brick to expand without the risk of its spalling during the temperature increase of the refractory lining.

With respect to the refractory lining obtained by means of the bricks, Fig. 11 illustrates the mutual arrangement of bricks in accordance with the fifth embodiment, the bricks being mutually juxtaposed in several successive superposed rows. In this case, the straight line 10 (Fig. 10) is intentionally strongly inclined with respect to the radial direction of the metal shell (not shown) which direction passes, through the geometric centre of the brick 1.

Fig. 1 2 shows a detail of the lining on an enlarged scale, illustrating the compensation of taper by the inverted position of one brick in the row.

TABLE I Reference Type a b h I di dm3 25/60 06385 180 120 250 100 1000 3.75 25/30 06386 165 135 250 100 2250 3.75 25/16 06387 158 142 250 100 4438 3.75 25/8 06388 154 146 250 100 9125 3.75 25/0 06387 150 150 250 100 - 3.75 30/70 06389 185 115 300 100 986 4.50 30/40 06390 170 130 300 100 1950 4.50 30/20 06391 160 140 300 100 4200 4.50 30/8 06392 154 146 300 100 10950 4.50 30/0 06393 150 150 300 100 - 4.50 35/80 06394 190 110 350 100 963 5.25 35/40 06395 170 130 350 100 2275 5.25 35/20 06396 160 140 350 100 4900 5.25 35/8 06397 154 146 350 100 12775 5.25 35/0 00383 150 150 350 100 - 5.25 40/80 06398 190 110 400 100 1100 6.00 40/40 06399 170 130 400 100 2600 6.00 40/20 06400 160 140 400 100 5600 6.00 40/8 06401 154 146 400 100 14600 6.00 40/0 06402 150 150 400 100 - 6.00 TABLE II Reference Type a b h I di dm3 45/90 06403 195 105 450 100 1050 6.75 45/40 06404 170 130 450 100 2925 6.75 45/20 06405 160 140 450 100 6300 6.75 45/8 06406 154 146 450 100 16425 6.75 45/0 06407 150 150 450 100 - 6.75 50/100 06408 200 100 500 100 1000 7.50 50/60 06409 180 120 500 100 2000 7.50 50/36 06410 168 132 500 100 3667 7.50 50/20 06411 160 140 500 100 7000 7.50 50/8 06412 154 146 500 100 18250 7.50 50/0 01835 150 150 500 100 - 7.50 55/110 06413 205 95 550 100 950 8.25 55/60 06414 180 120 550 100 2200 8.25 55/36 06415 168 132 550 100 4033 8.25 55/20 06416 160 140 550 100 7700 8.25 55/8 06417 154 146 550 100 20075 8.25 55/0 06418 150 150 550 100 - 8.25 60/120 06419 210 90 600 100 900 9.00 60/60 06420 180 120 600 100 2400 9.00 60/36 06421 168 132 600 100 4400 9.00 60/20 06422 160 140 600 100 8400 9.00 60/8 06423 154 146 600 100 21900 9.00 60/0 06424 150 150 600 100 - 9.00 65/120 06425 210 90 650 100 975 9.75 65/60 06426 180 120 650 100 2600 9.75 65/36 06427 168 132 650 100 4767 9.75 65/20 06428 160 140 650 100 9100 9.75 65/8 06429 154 146 650 100 23725 9.75 65/0 06430 150 150 650 100 - 9.75

Claims

1. A refractory brick for lining a metallurgical container, the brick being defined by a plane upper face, a plane lower face, parallel and identical to the upper face, a square or rectangular inner face, a square or rectangular outer face, having a width greater than that of the inner face, and two non-parallel opposite lateral faces, in which the centre of the inner face is offset, parallel to the upper and lower faces, with respect to the straight line passing through the centre of the outer face and extending perpendicular to the outer face.

2. A brick as claimed in claim 1, in which the lateral faces are curved in the same direction and with the same curvature.

3. A brick as claimed in claim 1 or 2, in which an acute-angled edge formed by the inner face and one lateral face and an acute-angled edge formed by the outer face and the other lateral faces are bevelled over their entire height.

4. A brick as claimed in claim 1, in which the lateral faces each extend along an S-shaped curve which is symmetrical with respect to its centre, the curves curving in the same sense and having the same curvatures.

5. A metallurgical container having a metal shell and a lining comprising bricks according to any preceding claim.

6. A metallurgical container as claimed in claim 9 in which the lining comprises superposed rows of bricks about the axis of the metal shell and in each row, the bricks are inclined about their geometric centre with respect to the shell's radius passing through this centre, such that the lining acquires a given curvature.