US2085925A

US2085925A - Tuyere

Info

Publication number: US2085925A
Application number: US749371A
Authority: US
Inventors: Owen R Rice
Original assignee: FREYN ENGINEERING CO
Current assignee: FREYN ENGINEERING Co
Priority date: 1934-10-22
Filing date: 1934-10-22
Publication date: 1937-07-06
Anticipated expiration: 1954-07-06

Description

0. R. RICE July 6, 193

TUYERE 2 Sheets-Sheet 1 Filed Co t. 22, 1954 July 6,1937. o, R, RICE 2,035,925

- TUYERE I Filed Oct. 22, 1934 ZSheets-Sheet 2 Patented July 6, 1937 UNETED STATES TUYERE Owen R. Rice, Chicago, llll., assignor to Freyn Engineering Company, Chicago, 111., a corporationof Maine Application October 22, 1934, Serial No. 749,371

- 4 Claims.

The present invention relates to improvements in tuyeres.

More particularly the present invention re-.

' naces. l

A further object is to provide a tuyere having a refractory nose composed of a material similar to that deposited within a blast furnace in service to accomplish the result that said nose will effectually resist both oxidizing and reduc ing conditions which may exist in the vicinity of the tuyre.

A further object is to simplify the manufacture of tuyeres having preformed refractory blocks in the noses thereof.

A further object is to provide an improved method of making a, tuyre embodying preformed refractory blocks in the nose thereof.

Further objects will appear as the description proceeds.

Referring to the drawings t Figure 1 is a view in end elevation showing the nose portion of a tuyere embodying the principles of the present invention, illustrating particularly the disposition of refractory blocks within the nose portion of the tuyere;

Figure 2 is a fragmentary sectional view taken along the plane indicated by the arrows 22 of Figure 1;

Figure 3 is a view similar to Figure 2 but showing an alternative construction for holding the refractory blocks in place;

Figures 4 and 5 are Views in end elevation and side elevation, respectively, of the block appeare ing in Figure 2;

Figure 6 is a view in end elevation of the block appearing in Figure 3;

Figure '7 is a fragmentary View similar to Figure 1 but showing the arrangement of preformed refractory blocks for a different diameter of tuyere;

Figure 8 shows the arrangement of blocks for another diameter of tuyere;

Figure 9 shows the arrangement of blocks for another diameter of tuyere;

Figure 10 shows the arrangement of blocks for still another diameter of tuyere;

Figure 11 illustrates the method of spacing the refractory blocks preparatory to the operation of casting the tuyere;

Figure 12 is a fragmentary elevational view.

of the structure shown in Fig. 11;

Figure 13 is a View illustrating how a portion of a shim may remain after the casting operation; and

Figure 14 is a fragmentary elevational view of the structure shown in Figure 13. v

The present invention has been illustrated in connection with a tuyere of the type generally known as water-cooled. By reference to Figure 2 it will be noted that the tuyere comprises the inner cone wall I0, the outer cone wall H, and the front wall [2. Said Walls, together with a back wall (not illustrated), form a jacket for cooling medium, usually water, through which the cooling medium may flow in a continuous stream to carry away heat from; the metal of the tuyere. v i

Extending forwardly from the front, wall i 2 are the inner annular rib or fin l3 and the outer annular rib or fin M, which ribs or fins I3 and I4 are disposed coaxially of the tuyere. In the outwardly opening recess between the front wall- IE and the annular ribs l3 and M are a plurality of preformed segmentalblock's l5l5, which blocks, in order that they may fit approximately around the circumference of a circle, have side faces tapering toward one another.

In the manufacture of a tuyereembodying the principles of the present invention, the copper of the tuyere is cast around the preformed refractory blocks [5-45. struction illustrated in Figure 2, a dove-tailed tenon I6 is provided,"which tenon extends circumferentially of the tuyere in the space provided by the wall'lZand the annular ribs or fins l3 and I4. Y

' In the construction illustrated in Figure 3, the faces of the refractory blocks l5'l5, which face the base of the tuyere, are provided with a pair of holes l'l-ll. These holes are disposed at an angle one to the other so that when theyare filled up with copper in the casting operation to form lugs, indicated by the numerals lla-l'la, the blocks are held firmly in a manner comparable to the toe-nailing of a board. In either of the constructions illustrated in Figures 2 and 3, the copper side walls or ribs l3 and I4 may burn away in service, but the blocks are securely held either by the tenon 16 or the lugs Ila-41a within the holes ll-ll, which tenons or lugs are themselves an intimate part of the cool water wall of the tuyere body. In the construction illustrated in Figure 3, a vent I8 is provided com- According to the conrnunicating with each pair of holes l'I-ll, whereby to facilitate the casting operation.

In the zone of the tuyres in a blast furnace there is present a highly scorifying fluid slag which will fiux with substances which are metallurgically either acid, such as silica, or basic, such as lime, or even neutral, such as alumina. Even the brickwork, which consists chiefly of some of these materials, is not resistant to this slag. The atmosphere in this zone of the furnace is prevailingly reducing, so that certain so-called refractories consisting of metallic oxides, such as chromic oxide, cannot endurein this atmosphere. There are times also when, locally, the atmosphere is highly oxidizing. Ordinary'carbon, sometimes regarded as a refractory, is far from proof against this condition.

According to the present invention, it is contemplated to use a substance such as is formed in the operation of a blast furnace. The furnaceborn substance referred to is graphite. Early in the operation of the furnace, graphite deposits naturally. upon the brick walls of the hearth and the lower. bosh, thisdeposit .being in the form of a heavy coating of laminated crystalline graphite. This graphite is produced by precipitation from the molten pig iron-which is really a super saturated solution of carbon in iron. It protects the brick against the fluxing action of the slag and the high temperature. It is itself unaffected by a reducing atmosphere. It is only very difiicultly oxidizable. It is impervious to the molten pig iron, of which it is really a product. It is the natural protective material in the furnace. It appears to be-the only universal refractory in the blast furnace sense. 'Without its protection the brick-structure would not survive.

The present invention therefore contemplates the use of crystalline graphite in the tuyere nose as a protective agent. In casting copper about a preformed rigid core of graphite, difficulty will be encountered due to the tendency of the copper to split upon cooling. This is because the coefficient of expansion of copper is higher than that of crystalline graphite. Moreover, since tuyeres are made in many sizes, it would be necessary to have on hand many sizes of crystalline graphite cores. In order to simplify the matter of stocking cores, and for the further purpose of overcoming the difficulty of splitting of the copper upon cooling, the present invention contemplates the use of a plurality of segmental preformed blocks which can be disposed circularly to form a core of any preferred diameter, within limits. Figure 1 shows a core made up of nine full blocks l5 and one out block, the cut block being indicated by the numeral [9. In the operation of casting the tuyere, shims .2B (Fig. 11) of volatile substance, such as wood or paper, may be Alla-20a in Figure 13.

Figures 1, 8, 9 and 10 indicate relative positions of blocks such as shown in Figure 1, but for tuyres of different diameters.

The present invention has the advantage that the nose of the tuyere is protected by a refractory suchas is a result of the furnace operation and therefore is immune to the destructive forces within the furnace. By reason of the fact that the refractory is cast within the tuyere in the form of a plurality of preformed blocks, it is a simple matter to provide for the casting of different sizes of tuyeres as required, and, further, it is a simple matter to provide for the differences in the co-efficient of expansion of the copper and the blocks, whereby the blocks may-move in the cooling operation to allow contraction of the copper-while cooling, whereby to avoid splitting of the copper.

The present disclosure is of course subject to modification. It is intended to cover all such modifications that fall within the scope of the appended claims. 7

What is claimed isv1. A blast furnace tuyre having an annular water jacket in the body portion thereof and a nose portion of crystalline graphite:

2. A blast furnace tuyere comprising a metallic body having a cooling chamber formed therein and having a nose portion including a plurality of irnperforatev annular fins with an open space.

between them extending beyond the end of said cooling chamber, anda set of preformed circularly disposed graphite blocks disposed between said fins and keyed to said body portion.

3. A blast furnace tuyere comprising a metallic body having a cooling chamber formed therein and having a nose portion including a plurality of imperforatenannular fins with an open space between them'extending beyond the end of said cooling chamber, and a set of preformed circularly disposed refractory blocks'disposed between said fins and keyed to said body portion.

4. An assembly of elements for the manufacture of a tuyere comprising a plurality of circularly disposed refractory blocks and members of volatile material for spacing said blocks apart circumferentia'lly."

' OWEN R. RICE;