US3744778A - Sintering machine - Google Patents

Abstract

In a sintering machine a travelling grate has a lower run and an upper run which is adapted to carry a bed of sinter mix which is in part combustible and discharged from the grate in the region of a downstream end of the upper run. Wind boxes are arranged below the lower run for drawing air through the bed and withdrawing combustion gases from the same. One or two conduits are arranged beneath the lower run communicating with the wind boxes. The conduits are so arranged as to intercept residual quantities of sinter mix which adhere to the grate and drop off the same as it moves in the lower run.

Description

United States Patent 1191 Biihner 1451 July 10, 1973 SINTERING MACHINE 2,987,307 6/1961 Homan .1 266/21 t li B"h [75] [men or Wu u Essen' Germany Primary Examiner.lohn J. Cumby [73] Assignee: Heinrich Koppers GmbH, Essen, AnomeyMichael S. Striker Germany [22] Filed: July 12, 1971 RACT In a sinterin machine a travellin rate has lower run A 1 g g g a [21] pp! No 61,792 and an upper run which is adapted to carry a bed of sinter mix which is in part combustible and discharged [30] Foreign Application Priority Data from the grate in the region of a downstream end of the July 18, 1970 Germany P 20 35 782.8 pp run. Wind boxes are arranged below the lower run for drawing air through the bed and withdrawing [52] U.S. Cl. 266/21 mb i n gases from the same. One or two conduits [51] Int. Cl. F27b 9/00 r r nge eneath the lower run communicating [58] Field of Search 263/28; 266/21 wi h h wind oxes- The conduits are so arranged as to intercept residual quantities of sinter mix which ad- [56] References Cited here to the grate and drop off the same as it moves in UNITED STATES PATENTS the lower 3,635,003 II 1972 Schindling 263/28 7 Claims, 2 Drawing Figures PAIENIEUJI'MOW 3.744.778

farm 1 {If 2 INVENTQR WILL) E UHNER .BY: ism

4770K N5 y SINTERING MACHINE BACKGROUND OF THE INVENTION The present invention relates generally to the sintering of metals, and more particularly to a machine for carrying out such sintering. Still more particularly the invention relates to a continuous sintering machine.

Continuous sintering machines are already known. Generally speaking, they are used for the sintering of ore fines or other finely divided iron-bearing material, which is intimately mixed with an appropriate quantity of finely divided fuel. These machines utilize a travelling grate for pallets on which a bed of the sinter mix is deposited. Near the head or feed end of the grate, the bed is ignited on the surface in suitable manner and, as the mixture moves along on the travelling grate, air is pulled through the mixture in downward direction in order to burn the fuel component of the mixture by downdraft combustion. The movement of the air is effected by the arrangement of wind boxes beneath the upper run of the continuous grate, and as the grates or pallets move continuously over the wind boxes towards the discharge end of the upper run, the combustion front in the bed moves progressively downward whereby the sinterable particles of this sinter mix become sintered.

A more detailed discussion of the sintering process and of continuous sintering machines is not believed to be necessary because those skilled in the art will be conversant with these factors. However, if a more detailed discussion is desired, reference may be had to The Making, Shaping and Treating of Steel, Eighth Edition, published by the United States Steel Corporation, where such a discussion may be found on pages 189 ff.

The known continuous sintering machines are provided at opposite sides of the machine, located approximately at the level of the lower run of the continuous travelling grate, with two conduits which communicate with the wind boxes and in which combustion gases drawn by the wind boxes from the travelling bed of sin.- ter material are collected. Located between these conduits beneath the lower run of the continuous travelling grate is a collecting trough whose purpose is to intercept and collect such residual quantities of the sinter mix which adhere to the grate as the majority of the mix is discharged at the lower end of the upper run. This residual adhering material falls off those portions of the grate which travel along the lower run and, as pointed out above, is to be intercepted and collected. Both the trough and the conduits extend in longitudinal direction of the lower run, but the conduits are located laterally outwardly of the grate.

The problem with these prior-art machines is that the overall width of the machine and of the building which houses the machine must be rather large, in any case significantly larger than would be required due to the width of the travelling grate itself. This is occasioned not only by the location of the conduits laterally of the grate per se, but by the fact that the conduits are of relatively large cross-sectional configuration due to the need for conveying large quantities of air and gas.

SUMMARY OF THE INVENTION It is, accordingly, an object of the present invention to overcome the disadvantages of the prior art.

More particularly it is an object of the present invention to provide an improved continuous sintering machine of the type under discussion which is not possessed of these disadvantages.

A concomitant object is to provide such an improved sintering machine which makes it possible to have lesser space requirements for its installation, and which concomitantly requires a smaller surrounding structure such as a building housing the machine, whereby the costs of building and installing such a machine are reduced.

In pursuance of the above objects, and of others which will become apparent hereafter, one feature of the invention resides in a sintering machine which, briefly stated, comprises travelling grate means having a lower run, and an upper run adapted to carry a bed of sinter mix which is in part combustible and which is discharged from the grate means in the region of a downstream end of the upper run. Wind box means is located beneath the upper run for drawing air through the bed and withdrawing combustion gases from the same. Conduit means communicates with the wind box means and extends longitudinally of the lower run beneath the same, this conduit means is arranged for intercepting residual quantities of sinter mix which descend from the grate means during travel thereof in the lower run.

Inthis manner the conduit means is now no longer located laterally outwardly of the travelling grate, thereby reducing the lateral dimensions of the machine, and at the same time it performs the additional function of intercepting the residual quantities of sinter mix which fall off the travelling grate as the latter moves through the lower run.

According to one embodiment of the invention the conduit means may be in form of two parallel conduits between which a gap is defined extending longitudinally of the lower run, and in which gap a plurality of longitudinally arrayed funnels is mounted into which the intercepted sinter mix falls and which communicate via tubes, conduits or the like with a transporting device located downwardly and onto or into which the intercepted material is discharged. Such a transporting device may for instance be a conveyor belt or the like.

It is also possible, however, to arrange the two parallel conduits directly adjacent one another without the aforementioned gap, so that together they define a closed intercepting trough. The removal of the intercepted material from this trough can then be effected by another suitable device, for instance by an essentially horizontally acting transporting device such as a chain conveyor or scraper, a scraper shovel or the like which may be mounted in and movable in this trough.

Still a further possibility is to provide a single conduit, that is in effect to locate the two parallel conduits directly adjacent one another and to remove the separating wall so that they constitute a single conduit. In this case the upper wall thereof is configurated in trough-shaped manner to intercept descending residual sinter mix. The interior of this single conduit may advantageously be configurated in the region of the bottom wall to produce another trough-shaped receptacle into which particulate matter, such as'dust and the like which is entrained in the incoming gas stream, is allowed to settle and from which a suitable removal or transporting device, again such as chain scraper, a

scraper shovel or the like, can remove the accumulated particulate matter.

As a terminal element of a transporting plow or similar removal device it is possible to provide a vessel which is mounted on pressure-measuring units, suchv as a bunker or the like, whose removing conduit is controlled by the pressure-measuring devices, with a residual quantity of particulate matter remaining in the vessel and serving to provide a seal with respect to the underpressure which prevails in the conduit.

In order to simplify the expenses necessary involved in constructing a building for the machine, it is further possible to replace the crane which is customarily mounted above the sintering machine with a portal crane.

In this case it is possible to construct the portal crane to permit a lateral movement of the carriage thereof in the region of the feed end or of the ignition furnace at which the sinter mix is ignited, and also in the region of the discharge or downstream end of the upper run. Such an arrangement makes it possible to more rapidly gain access to the crane in order to permit removal and replacement of components.

Because it is not necessary that the crane be capable of moving along the entire length of the building with its maximum load, an interlock may be provided which permits operation of the crane with maximum load only in the region of the hot pre-breaker and the hot screens, whereas in the remaining part of the building the crane can operate only with a partial load. In such a case the construction of the building surrounding the machine, and in particular above the machine itself, can be relatively light, for instance on a tubular frame which is less expensive than would otherwise be the case.

The novel features which are considered as characteristic for the invention are set forth in particular in the appended claims. The invention itself, however, both as to its construction and its method of operation, together with additional objects and advantages thereof, will be best understood from the following description of specific embodiments when read in connection with the accompanying drawing.

BRIEF DESCRIPTION OF THE DRAWING FIG. 1 is a somewhat diagrammatic side elevation illustrating a continuous sintering machine of the type in question; and

FIG. 2 is a section taken on line II-Il of FIG. 1.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Discussing now the drawing in detail it will be seen that in the sintering machine, which in its essential noninventive aspects may be the same or analogous to those known from the prior art, reference numeral 1 identifies the diagrammatically illustrated pallets a chain of which makes up a continuous travelling grate. They are guided for movement on wheels 2 on endless guide rails 3 and are pressed onto the upper run by a drive wheel 4. On the upper run they advance in the direction of the arrow A in FIG. 1, and are then reversed in direction to enter into the lower run, by means of a curved track portion 5.

In known manner, the supply of sinter mix to form a bed on the individual grate pallets l, the ignition and the sintering of the mix takes place while the pallets 1 move along the upper run in the direction of the arrow A; devices for this purpose are well known and require no discussion, particularly because they do not in them selves form a part of the invention. The sintering is completed when the pallets I reach the left-hand or downstream end of the upper run and the sinter is discharged from the pallets as they are reversed in the curved guide track portion 5. It is then supplied to nonillustrated breaking and screening devices.

In known manner, air is drawn downwardly through the bed of sinter mix on the pallets] as the latter move in the direction of the arrow A in the upper run. For this purpose a plurality of wind boxes 6 of known construction and operation is located or arranged between the upper run of the travelling grate, and are connected via pipes or the like 7 which extend at opposite lateral sides of the machine, with two combustion gas conducting conduits 8 (see in particular FIG. 2) located beneath the lower run and extending in longitudinal direction of the latter.

FIG. 2 shows clearly that in the illustrated embodiment the conduits 8 extend in parallelism with one another, being arranged so closely in side-by-side relationship that only a relatively narrow upright gap 9 remains between them. The upper inclined surface portions 10 of the conduits 8, which are here of hexagonal cross-section, together define an intercepting hopper for that residual quantity of mix which adheres to the pallets as they discharge the sinter, and which drops off as the pallets move along the lower run. As such material drops off it falls onto the surfaces 10 and slides into the upper end of the gap 9 in which in the illustrated embodiment a plurality of funnel-shaped hoppers 11 are located, being arrayed in longitudinal direction of the gap 9. From these hoppers 11 the material moves via tubes 12 onto a transporting device, here illustrated as a belt conveyor 13, and by' this it is carried away and may be supplied to additional transporting devices to be advanced to a location where it can be subjected to further use. In many instances it will be possible to use the transporting device 13 at the same time also for transporting away particulate matter, such as dust, which has been entrained by the air and gas moving through the conduits 8 and which is removed from such air and gas by suitable dust separators.

Located beneath the conduits 8, which extend to non-illustrated blowers with whose suction side they are connected, are chain scrapers or conveyors 14 which convey the dust and other particulate material which enters the conduits 8 because it is entrained in the incoming air and gas, into a receptacle 15 which is supported on pressure-measuring units or devices 16. The latter so control the removal of the dust from the receptacle or vessel I5 onto a plate conveyor 17 or different transporting devices, that a residual quantity of dust remains in the vessel 15 and effects a seal of the latter with reference to the under-pressure prevailing in the conduits 8.

As is particularly clearly shown in FIG. 2, the arrangement of the conduits 8 in the exemplary embodiment eliminates the need for a separate intercepting trough for the residual sinter mix. Furthermore, the width of the building 18 surrounding the machine can of course be reduced to a minimum with this arrangement, and better space distribution than heretofore is obtained for arranging workshops, storage areas, control rooms and the like within the housing 18. The

space between the conduits 8 permits the arrangement of center supports 19 which in turn also permits a more advantageous dimensioning of the supporting elements of the building 18.

It is emphasized again that the space or gap 9 could be omitted and that the conduits could be located directly adjacent one another'as pointed out earlier, or that they could be combined to form a single unitary conduit.

It will be understood that each of the elements described above, or two or more together, may also find a useful application in other types of constructions differing from the types described above.

While the invention has been illustrated and described as embodied in a continuous sintering machine, it is not intended to be limited to the details shown, since various modifications and structural changes may be made without departing in any way from the spirit of the present invention.

Without further analysis, the foregoing will so fully reveal the gist of the present invention that others can by applying current knowledge readily adapt it for various applications without omitting features that, from the standpoint of prior art, fairly constitute essential characteristics of the generic or specific aspects of this invention and, therefore, such adaptations should and are intended to be comprehended within the meaning and range of equivalence of the following claims.

What is claimed as new and described to be protected by Letters Patent is:

1. In a sintering machine, in combination, travelling grate means having a lower run, and an upper run adapted to carry a bed of sinter mix which is in part combustible and is discharged from said grate means in the region of the downstream end of said upper run; wind box means beneath said upper run for drawing air through said bed and withdrawing combustion gases from the same; and conduit means communicating with said wind box means and extending longitudinally of said lower run beneath the same, said conduit means being arranged to define with one another intercepting means for intercepting residual quantities of sinter mix descending from said grate means during travel thereof in said lower run.

2. In a sintering machine as defined in claim 1, wherein said conduit means comprises a pair of conduits arranged in side-by-side relationship and defining with one another an upright gap extending longitudinally of said lower run and constituting said intercepting means adapted to receive the intercepted residual quantities of sinter mix.

3. In a sintering machine as defined in claim 2; further comprising a plurality of funnel-shaped guide elements located in said gap and arranged longitudinally thereof; a transporting device for said intercepted residual quantities of sinter mix downwardly spaced from said gap; and guide means extending from said guide elements to said transporting device for guiding intercepted mix to the latter.

4. In a sintering machine as defined in claim 1, said conduit means comprising a pair of conduits arranged in side-by-side relationship and defining with one another an upright gap extending longitudinally of said lower run, and having upwardly directed surface portions facing said lower run and defining a downwardly convergent chute communicating with said gap.

5. In a sintering machine as defined in claim 4; and further comprising transport means for transporting intercepted residual mix from said gap in a substantially horizontal direction.

6. In a sintering machine as defined in claim 1, said conduit means comprising a conduit having an upper wall portion configurated for intercepting said residual mix, and a lower wall portion configurated interiorly of said conduit as a troughshaped receptacle for particulate matter entrained in air and combustion gases admitted into said conduit from said wind box means; and further comprising removing means in said conduit for removing the particulate matter from said receptacle.

7. In a sintering machine as defined in claim 6, said removing means comprising a vessel accommodating a residual quantity of particulate matter for sealing said vessel with reference to said conduit, and pressuremeasuring units supporting said vessel.

Claims (7)

1. In a sintering machine, in combination, travelling grate meAns having a lower run, and an upper run adapted to carry a bed of sinter mix which is in part combustible and is discharged from said grate means in the region of the downstream end of said upper run; wind box means beneath said upper run for drawing air through said bed and withdrawing combustion gases from the same; and conduit means communicating with said wind box means and extending longitudinally of said lower run beneath the same, said conduit means being arranged to define with one another intercepting means for intercepting residual quantities of sinter mix descending from said grate means during travel thereof in said lower run.

2. In a sintering machine as defined in claim 1, wherein said conduit means comprises a pair of conduits arranged in side-by-side relationship and defining with one another an upright gap extending longitudinally of said lower run and constituting said intercepting means adapted to receive the intercepted residual quantities of sinter mix.

3. In a sintering machine as defined in claim 2; further comprising a plurality of funnel-shaped guide elements located in said gap and arranged longitudinally thereof; a transporting device for said intercepted residual quantities of sinter mix downwardly spaced from said gap; and guide means extending from said guide elements to said transporting device for guiding intercepted mix to the latter.

4. In a sintering machine as defined in claim 1, said conduit means comprising a pair of conduits arranged in side-by-side relationship and defining with one another an upright gap extending longitudinally of said lower run, and having upwardly directed surface portions facing said lower run and defining a downwardly convergent chute communicating with said gap.

5. In a sintering machine as defined in claim 4; and further comprising transport means for transporting intercepted residual mix from said gap in a substantially horizontal direction.

6. In a sintering machine as defined in claim 1, said conduit means comprising a conduit having an upper wall portion configurated for intercepting said residual mix, and a lower wall portion configurated interiorly of said conduit as a troughshaped receptacle for particulate matter entrained in air and combustion gases admitted into said conduit from said wind box means; and further comprising removing means in said conduit for removing the particulate matter from said receptacle.

7. In a sintering machine as defined in claim 6, said removing means comprising a vessel accommodating a residual quantity of particulate matter for sealing said vessel with reference to said conduit, and pressure-measuring units supporting said vessel.

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