US2705000A - Tuyere - Google Patents

Description

March 29, 1955 5 P, KINNEY 2,705,000

TUYERE Filed March 2l, 1950 Gttornegs United States Patent O 2,105,000 TUYRE Selwyne P. Kinney, Crafton, Pa., assignor to S. P. Kinney Engineers, Inc., Carnegie, Pa., a corporation of Pennsylvania Application March 21, 1950, Serial No. 150,946

2 Claims. (Cl. 1226.6)

This invention relates to tuyres such as those used to introduce the air blast into a blast furnace, and has for its object to provide a tuyre which will give a longer life in service.

The conventional tuyre used in blast furnaces is usually formed of copper or bronze because of the high thermal conductivity of these metals. These tuyres are large nozzle-shaped bodies slightly tapered with a central air passage therethrough and with an annular water space throughout substantially the full length thereof. At the inner end tuyres covered by the Butler and Henry patents, Nos. 1,969,294, dated August 7, 1934, and 1,962,593, dated June 12, 1934, respectively, usually have a thickened section, and often the metal in the inner end or nose of the tuyre is thickened to resist erosion and burning. Notwithstanding this thickening of the nose, the metal under the nose will cut or burn away, so that the tuyre will leak and require replacement. In blast furnace practice, it is often found that the tuyres are attacked by hot metal that is held up under the tuyre in coke and slag. If the slag in the furnace becomes partially viscous, its free flow may be retarded and a mass of fine coke and slag may form under the nose of all or part of the tuyres. Under these conditions the copper of the tuyre may be quickly attacked and the lower part of the tuyre may be attacked and ultimately punctured.

With the present invention, a substantially longer life is assured without change in the overall dimensions or outside shape of the tuyre, and with very little added cost.

According to the present invention, the outer wall is circular in section, but the inner surface of this wall defines in the lower half of the tuyre, an arc which is eccentric to the outside, whereby the wall under the nose is thicker than the top wall. Toward the back end of the tuyre, the two circles become fully concentric, whereby this thicker portion tapers gradually to the normal wall thickness.

This not only provides protection back of the nose against undercutting, but it also gives a water-circulating space where the water has a non-uniform velocity with the greatest velocity over this thickened part giving an especially eective scouring action to this very vulnerable point to carry away the heat and also retard sedimentation which otherwise tends to occur to a considerable extent at this point.

Blast furnace practice has shown that under certain conditions of operation that a building of deposits occur on the bosh of the furnace. These deposits hold up or retard the free ow of molten iron in its travel to the hearth. This condition results in attack of the top of the tuyre and in such case the thicker portion of the tuyre is turned upward, thus retarding the attack on the tuyre shell.

Where furnace operations are smooth and there is no tendency to attack the top or bottom of tuyres as described above, the main cause of wear on the tuyre is due to the passage of stock over the surface of the copper. In this case, the thicker portion of the body is turned upward and life of the tuyre is materially lengthened because of the thickened sections.

My invention may be more fully understood by reference to the accompanying drawing, in which:

Fig. 1 is a longitudinal section through a tuyre embodying my invention;

Fig. 2 is a transverse section in the plane of line II--II of Fig. 1;

ICC

Fig. 3 is a view similar to Fig. 1 of a slightly modified tuyre;

Fig. 4 is a transverse section in the plane of line IV-IV of Fig. 3; and

Fig. 5 is an elevation looking toward the rear end of the tuyre shown in Fig. 3.

Referring first to Figs. 1 and 2, the tuyre shown is of generally conventional contour having an end wall 2 with openings 3 and 4 therein at the top and bottom respectively, into which water connections may be screwed. Extending forwardly from the end wall, the tuyre has an outer shell 5, the exterior of which is cylindrical and concentric with the longitudinal axis of tuyre opening 6. There is an inner shell 7 forming the central passageway 6, and it is concentric with the exterior of the shell 5. The two shells come together at the nose 8 ofl the tuyre, and this nose 8 is of thickened section, being thicker than 7 or the upper part of the shell 5. At the rear end of the tuyre there is an annularly-thickened part 9. Between the inner and outer shells 5 and 7 is a water-circulating space 10.

According to the present invention, the inner wall of the shell 10 is also substantially circular, but its center is located above the longitudinal axis A-A of the tuyre. Actually the upper part of the inner wall is concentric with the outer surface, while only the lower part is eccentric as is best seen in Fig. 2. This results in a thickening of the outer shell of the tuyre in the bottom half of the tuyre. The thickening begins, as shown in Fig. 2, at about positions B and B', sometimes designated the three and nine oclock positions, while the maximum thickness is reached from these positions, or at the six oclock position at the very bottom of the tuyre.

Adjacent the base portion 9 of the tuyre the inner walls and outer walls of the outer shell are substantially concentric. This results in a gradual diminishing of the thickness of the wall in the lower part of the shell of the tuyre from the nose toward the base.

`By reason of the construction herein described, the under side of the tuyre at the point where cutting most frequently occurs, the tuyre is thickened to more effectively resist cutting, while very little Weight is added to the overall weight of the tuyre and the outside contour and dimensions of the tuyre are not altered. The water passage, however, inside the tuyre, is altered in a desirable manner. By reason of the thickening of the lower part of the wall internally, the water-circulating passage at the nose of the tuyre in the lower part is restricted more than at any other point in the chamber 10. This results in a higher velocity of circulation at this point where the water normally tends to be the most stagnant, and where sedimentation occurs. By reason of this increased velocity, lthe water scours the surface of the metal with higher velocity, and therefore sweeps the heat away and retards sedimentation. Also because of the taper in a longitudinal direction along the bottom wall of the tuyre, gravitation favors the movement of sediment toward the base of the tuyre.

The water inlet .pipe is preferably connected to the tuyre at the opening 4 and water is removed through the opening 3 and there may be one or more internal bales as indicated at 11 to prevent a direct circulation of water around the tuyre at the base with relatively low circulation at the forward end.

The arrangement shown in Figs. 3, 4 and 5 is substantially the same as that previously described, and similar reference numerals have been used to indicate the corresponding parts. However in this tuyre I have shown concentric fins 12 on the upper half of the nose of the tuyre in the water-circulating chamber providing an extended surface for conducting heat from the thickened nose of the tuyre back into the water. Such tins are provided only in the upper half, because of the restriction of the water space by the thickening of the lower wall. I have also shown in this modiiication holes 3 and 4 in addition to the holes 3 and 4, so that the water circulation can be changed. For example, 3 and 4 may be inlet passages, and 3' and 4 may be outlet passages, or other connection arrangements can be used.

While I have shown and described certain specific embodiments of my invention, it will be understood that the invention is not restricted to the specific forms of tuyres illustrated, but is adapted to heavy-nosed tuyres of various shapes.

I claim:

1. A water cooled tuyre subject to unequal temperatures about its upper and lower faces comprising inner and outer hollow spaced shell portions providing between them a water chamber, the shell portions being joined at their forward ends by an integral nose portion and at their rear ends by an end wall, spaced water inlet and outlet connections extending through the end wall into communication with the water chamber providing water circulation through said chamber and between the said shell portions, the inner face of the wall of the bottom longitudinal half of the outer shell portion being eccentrically disposed to the outer face of the adjacent inner shell portion and having an axis of eccentricity angularly disposed to the axis of the tuyre providing a tapering cross section in the adjacent outer shell wall portion reducing in thickness from adjacent the tuyre nose portion to adjacent the tuyre end wall and of increasing cross section from adjacent the longitudinal center line of the tuyre to the outermost peripheral portion of the inner face of the wall of the outer shell, whereby water ow through the chamber in the area of the varying outer wall thickness has its highest velocity adjacent the nose of the tuyre and decreases in velocity towards the tuyre end wall.

2. The water cooled tuyre defined in claim 1 wherein a baffle plate is disposed in the water chamber adjacent the Water outlet impeding direct ow of water about the water chamber adjacent the tuyre end wall and insuring flow of water into the tuyre nose.

References Cited in the tile of this patent UNITED STATES PATENTS Re. 19,980 Fox May 26, 1936 1,161,206 Fraser Nov. 23, 1915 1,775,608 vVan Devanter Sept. 9, 1930 1,868,306 Boland July 19, 1932 1,962,593 Henry June 12, 1934 1,969,294 Butler Aug. 7, 1934 2,056,264 Fox Oct. 6, 1936 2,200,497 Fox May 14, 1940 2,398,098 Kinney Apr. 9, 1946

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