US3159290A - Continuous feed cupola - Google Patents

Description

Dec. 1, 1964 w. K. HEssE CONTINUOUS FEED CUPOLA 2 Sheets-Sheet 1 Filed May 3l 1961 INVENTOR WAN-5,47 K. /ES'S BY ATTORNEY Dec. 1, 1964 w` K. HESSE 3,159,290

CONTINUOUS FEED CUPOLA Filed May 51, 1961 2 Sheets-Sheet 2 INVENTOR. MUER K. Hess:

3,159,299 INTENUGUS FEED CUPQLA Walter K. Hesse, Martinsvilie, NJ., assigner to Eohns- Mam/ide Corporation, New York, NX., a corporation of New York Fitted May 31, 1%1, Ser. No. 113,696

3 Claims. 21e-18.2)

This invention relates to a continuousfeed mechanism for cupolas of the type used for melting the materials, such as rock, glass and slag to be converted into fiber using a combustion agent such as coke or other carbonaceous material.

In this type cupola, as particularly used over the past many years in the production of mineral wool, it has been customary to provide batch feeding of slag and coke into the cupola with only moderate and sporadic attempts to place these materials in their most favorable positions in the cupola. The result has been that unnecessary variations in the feed rates, the slag-coke ratio and in the conditions of the issuing molten slag stream have been accepted as unavoidable.

In accordance with the present invention it has been found possible to introduce slag or rock mixtures and coke into typical upright mineral wool cupolas, fed from above as is customary, and to feed these materials on a continuous basis with only small and inconsequential variations in the feed rate or in the positioning of the materials in the cupola. Y

Tests have shown that by use of the present invention the materials can be uniformly placed in the cupola hour after hour in the most desirable conditions required for economy of operation, producing a slag stream of substantially uniform volume, temperature, and viscosity definitely superior to those heretofore produced for berization into light weight mineral Wool products.

It is thus a primary object of the invention to provide a new and improved feeding mechanism for introducing the charge for the cupola, comprising the material to be melted and the required amount of combustion agent, at a substantially uniform rate, with the charge introduced into the upper portion of the cupola, over the burden previously placed in the cupola.

It is a further object to provide a feeding apparatus of this type in which the nes and coarser particles are suitably placed in the cupola for maximum economy and efficiency and in which the rate of feed varies only slightly and for short periods of time from the normal feeding rate established for the particular cupola and charge being utilized.

The above and other objects will be clear from the following description when considered in connection with the drawings wherein:

FIG. 1 is a vertical sectional view of the cupola and feed mechanism, parts being in elevation;

FIG. 2 is a horizontal sectional view thereof, taken on the line 2--2 of FIG. 1, parts being in elevation;

FIG. 3 is an elevational view of the cupola and feed mechanism, taken on the line 3 3 of FIG. 1, parts being broken away;

FIG. 4 is a diagrammatic view illustrating the relation of the various control and operating elements of the equipment.

Referring to the details of the drawings the cupola 2 is of any preferred design of upright cupola, that shown having a water jacketed cylindrical body, preferably of 3 to 5 feet in diameter. The lower portion, where the molten material is withdrawn and formed into mineral wool fibers is omitted, as it is a standard construction.

The devices for providing a continuous supply of slag and coke include two or more hoppers or bins 4, each containing a substantial quantity of materials, one pref- Y United States atent Patented Dec. l, 1964 erably containing coke and the other a mixture of materials to be melted. It is possible to pre-mix the coke with the materials to be melted and to use one bin for the supply. It is also possible to provide several bins for the coke and for each of the materials to be melted. However it has been found that best results are obtained by supplying one bin for coke and another for the pre-mixed materials to be melted.

The charge of materials to be melted for forming mineral wool varies considerably, depending on what materials are readily available, the type product desired, etc.`

Formulae for this purpose are well known, mixtures composed mainly of iron slag with minor proportions of modifying mineral materials, including some fines of these materials, being customarily used. The charge is referred to herein as slag charge, it being understood that by this term is meant any meltable slag or stone-like material or mixture available for the production of mineral Wool.

The hoppers or bins 4, preferably of reduced Width at their lower ends as shown at 5, may be provided with any type of removal equipment which can be operated on a continuous basis and which will discharge a uniform quantity of the stored materials. There is illustrated a preferred mechanism for this purpose, comprising reciprocating floor panels 6, supported on rollers 3 and movable back and forth under the stored materials. The panels 6 t snugly against the bottom walls of the bins on the side and back walls thereof but the front wall is cut away as shown at 1t). The oor panels extend outwardly beyond the front wall to provide a lip 12 on which the removed materials rest until the panel is withdrawn and the materials thereon are forced off of the panel by pressure of the materials in the bin. Adjustable hinged or sliding panels may be employed to provide exact control of the height and width of the openings 10.

Materials discharged from the bins by floor panels 6 fall upon a conveyor, shown as a conveyor belt 7, positioned beneath and in front of the leading edges of the ioor panels 6. The belt carries the mixed discharged materials to an inclined chute 7a. This chute guides the materials into the upper open end of a rotary distributor chute 9 in the cupola, the chute 9 being formed with a side opening 9a for discharging the materials outwardly in a circular pattern or ring near the outer walls of the cupola. The rotary chute is carried by a supporting shaft 11 mounted on suitable bearings in a supporting bracket 11a in the upper portion of the cupola and is caused to rotate by means of gears 13 and motor-driven shaft 19 projecting through the cupola wall. The shaft 11 is positioned centrally of the cupola, the rotary chute 9 being positioned at a height such that its bottom edge is spaced a short distance above the normal upper surface of the burden in the cupola. The rotary distributingV chute is of particular importance in the present invention since the usual burden contains many fines which should be carefully distributed and placed principally away from the center of the cupola, as provided by the outwardly directed spout 9a.

In order to regulate the relative quantity of each material discharged and to provide for adjustment from time to time of the relative quantities of each, the actuating mechanism illustrated in the'drawings has been found to be particularly satisfactory. There is provided an actuating beam 14, pivoted at 15, near the 'center thereof,

to an adjustable supporting bar 16. The supporting bar is adjustable in slots 17 on the base 18. The connection at the pivot 15 permits adjustment of the pivot with respect to the length of the beam, to correspond to the length-wise adjustment of the supporting bar. The beam is connected to the oor panels of the bins by means of links 2? pivotally connected to the beam on opposite sides ofthe hinge point 15 and to the oor panels. The beam is caused to oscillate, to move the floor panels bach and forth, by means of motor 21 and associated speedreducing .gear 22 mounted on bracket 23 which may be supported on the adjacent supply bin. The reducing gear box includes a slow moving power shaft at its lower end,

v formed witha crank arm 24, the crank pin of which is ,levery isshown in normal position.V Movementr ahead or tothe vright,`as viewed in FIGy/l, produces V low speed aand to the left produces higlzierV than normalY speed. VYStops (FIG. 2) may be provided to prevent excessive movement of the arm 23 which might damage the controLThe control arm is biased toward the higherY speed positionby tension spring 31. v f It will be understoodthat more adjustment positions could be provided and that normal feed could be set, for example, somewhat higher than desired to maintain'a constant level inthe cupola, in which case a lower speed would be the only lvariation required. This applies equally where-the feed vis set lower thany desired, adjustment for higher speed only being required. The presentinvention' provides for maintaining a stantially uniform depth of burden'by providing a shoe, maintained in contact with theA upper surface Vof the burden in the cupola for all normal operating conditions; Thus sub- A there is provided a contact shoe 32 rigidly connected' to a y mounting shaft 34, loosely mounted in guidebrackets secured to the'fwall of the cupola. The shaft 34 may have an adjustable ring 36 secured to its upper end toV prevent the bar and shoe from dropping down below the control area. Y v v For translating movements of the control shoe to the feed mechanismV and for periodically elevating the shoe to prevent itvfrom becoming buried in the chargedV materials, there is providedV a rigid lever bar 38 pivotally connected to a supporting Vbracket 39 mounted on the furnace wall. The'bar carries a yoke 42`at its inner end,

the yoke extending beneathk and engaging a ring 40',"

'adiustab'ly mountedon the Vshaft 34.` The outer end 43 of bar 3S carries a right-angled pin 47, slidably mounted in. slot '44 in a pitman or connecting rod 45, the lower endof which `is attached to the actuating pin of crank 46 rotated by motor y48 and reduction vgear49. YAn exact adjustment ofthe height ofthe burden in the cupola can b e made by simple adjustment of the rings 36 and 4d, n

Y such shown at 51, to provide a direct pull upon the arm 2,8, in opposition to the Atension provided by spring 31.

vThe parts are so weighted Yandbalanced that the shoe Y 32 normally rests upon or near the 'upper surface of the burden, 'theyoke 42 kof bar 3S bearing'against the yringV Y the pivot?. As the burden in the cupola is consumed theY shoe dropscorrespondingly, tilting the outer end ofV l bar 38 upwardly and if this movement is suicient the feed :any overlying burden, causing temporary shifting of control arm to slow position. When the slot 44 releases the outer end of bar 38 shoe 32 drops again by Vgravity to the upper surface of the burden in the cupola,

producing thefsetting for the feed mechanism correspond` ing to the new position of the shoe. Since the position of the shoe 32 corresponds generally with the radial position where the charge is deposited in the cupola, the burden presents a relatively flat surface to be contacted by the shoe, resulting in uniformity of operation.

Y The vspeed of movement of most elements of the ap#V paratus is not critical and in general the movements are slow. Thus the speed of the conveyor belt is not critical,

yits speed being regulated'to conveniently carry. the dis.

charged slag fand cokeimixture Vto the cupola. .The chargeovithdrawing operation is set to provide ysubstantially the required amount of slagfand'colce to replace that Vremoved. in the melting operation of the furnace.

f The slow speed and high speed may be set at ten percent totwenty percent below and above, respectively, the normal operating speed. The rotary chute 9 may be ful.

strokes perminute, that is, one or two r.p.m. of the crank arm do. l

It will be noted there is no synchronism between the various feeding, distributing and Vcontrol devices herein, but that instead there is a random supply of slag and coke to the sucessive areas in the cupola. It has been found that Vthe height of burdenV cangbe controlled within plus or minus about one inch, this-being well within the limits required to accomplish the benefits of a continuous cupola feeding operation as herein described. A v It has beenfound there'jare many beneiits, some unanticipated, in maintaining a substantially constant height -of burden in upright cupolas of the type herein described and in placingV the charge in a ring near the outer wall or at least removed from the center ofthe cupola. Depositing the charge inV a circular vpath results in a dis.

proportionate amount of the smaller particles and finesV remaining near the outer walls with the larger particles concentrated near the cente'rof the cupola. This division between small and large particles is shown 'in exaggerated form in the drawings to illustrate the effect. There are actually small andlarge particles scattered across' the burden, but with a greater concentration of lines nearer the walls and, of coarser particles near the center of the cupola; The draft through the center of the Ycupola i is thereby increased and the combustion area reaches well up into the center of the burden. The edge portions of the burden thus serve to insulate the. side walls alonga` substantialportionof the combustion zone, resulting in less heat loss, the smaller particles being gradually melted or consumed as they collapse into the lower portion of the combustion zone where this Zone spreads across the cupola. 'y v The result is Vthat there is a more uniformv discharge of molten slagfrom the cupola, the discharged 'stream -being of more uniform temperatureV and viscosity,' This has proventoV be of unexpected benefit in that the Vcolteslag-ratiocan be reduced and there is better density control of the berized product and avoidance of the well recognized wide range in weightrof iibe'rized product pro-V duced per unit VVoftirne, where the cupola isl fed in the y usual batch or intermittent manner. VIt is thus easier to motorcontrolv is'move'd to highV position, under the iniiu-l ence of spring 31. This condition isinterrupted periodically, desirably onceeve'ry Yminute or two, as the crank arm ILttimoves downwardly, causing a brief vengagement of the upper endof slot 44 with ipin 47 on the outer free V'end 'of'bar 38. The downward movement of the outer end ofvbar 3S elevates the shoeY upwardly through in part to the insulating etfect of the outer layer of lines meet manufacturing tolerances, with' actual savings due to the greater amountof liberized materials collected, due

` surrounding a portion of the combustion zone.

vmies, dependent on the spacing of the chute 9 above the burden in the cupola, the greater the spacing the nearer the discharged materials fall with respect to the Walls. The materials may also be discharged nearer the Walls by increasing the speed of rotation of the chute. Either of these methods affords a ready adjustment of the placement of the charge in the cupola as required for the particular charge materials being used and the operating conditions of the cupola.

The operation of the apparatus Will be clear from the above description. The initial charge is introduced and the charge ignited in any preferred manner. Thereafter the controls operate to maintain a substantially uniform depth of burden in the cupola due to the controls under the intluence of the shoe 32. The materials are deposited in a ring near the outer Walls so that the finer materials tend to accumulate near the walls and the coarser particles tend to fall toward the center. These particularly favorable operating conditions are continued indefinitely and without further attention except for maintaining a supply of slag and colre in the hoppers.

While the invention has been described in rather full detail, it will be understood that these details need not be strictly adhered to and that various changes and modications may suggest themselves to one skilled in the art, all falling Within the scope of the invention as defined by the subjoined claims.

What l claim is:

l. Apparatus for continuously introducing a charge of material to be melted and combustion agent into a cupola above the burden in said cupola comprising a plurality of bins containing either the material to be melted or the combustion agent, means responsive to a control device for removing varying amounts of said material to be melted and said combustion agent from said bins, means for commingling said removed material to be melted and said combustion agent, charging said cupola by introducing the commingled material to be melted and combustion agent into said cupola, a distributor in said cupola for receiving said commingled material to be melted and said combustion agent, means mounting said distributor for rotation about an axis substantially parallel tothe longitudinal axis of said cupola, means rotating said distributor to distribute said commingled material to be melted and said combustion agent in said cupola in a circular pattern spaced outwardly from the center of said cupola, said control device comprising a constant level contact member in said cupola, and means for periodically moving said contact member generally in a direction parallel to the longitudinal axis of said cupola from a position beneath the exposed surface of the burden of charged materials in said cupola to a position in contact With the free exposed surface of said burden.

2. Apparatus as dened in claim 1 wherein said distributor is positioned above the normal level ofthe burden in said cupola to cause said charging material to be dropped a predetermined distance onto the free surface of said burden so that a disproportionate share of larger particles fall inwardly toward the center of said cupola and smaller particles tend to remain in the position in which they are dropped, and means for maintaining a substantially uniform pile of burden in said cupola.

3. Apparatus as defined in claim 2 and further comprising means for varying the circular pattern of said charge comprising said commingled material to be melted and said combustion agent, to cause said charge to be supplied nearer the Walls or nearer the center of said cupola.

References Cited in the tile of this patent UNITED STATES PATENTS 955,615 Stone et al. Apr. 19, 1910 2,114,545 Slayter Apr. 19, 1938 2,408,221 Michel Sept. 24, 1946 2,654,594 Somogyi Get. 6, 1953 2,891,686 Roberson et al. June 23, 1959

Claims (1)

1. APPARATUS FOR CONTINUOUSLY INTRODUCING A CHARGE OF MATERIAL TO BE MELTED AND COMBUSTION AGENT INTO A CUPOLA ABOVE THE BURDEN IN SAID CUPOLA COMPRISING A PLURALITY OF BINS CONTAINING EITHER THE MATERIAL TO BE MELTED OR THE COMBUSTION AGENT, MEANS RESPONSIVE TO A CONTROL DEVICE FOR REMOVING VARYING AMOUNTS OF SAID MATERIAL TO BE MELTED AND SAID CONBUSTION AGENT FROM SAID BINS, MEANS FOR COMMINGLING SAID REMOVED MATERIAL TO BE MELTED AND SAID COMBUSTION AGENT, CHARGING SAID CUPOLA BY INTRODUCING THE COMMINGLED MATERIAL TO BE MELTED AND COMBUSTION AGENT INTO SAID CUPOLA, A DISTRIBUTOR IN SAID CUPOLA FOR RECEIVING SAID COMMINGLED MATERIAL TO BE MELTED AND SAID COMBUSTION AGENT, MEANS MOUNTING SAID DISTRIBUTOR FOR ROTATION ABOUT AN AXIS SUBSTANTIALLY PARALLEL TO THE LONGITUDINAL AXIS OF SAID CUPOLA, MEANS ROTATING SAID DISTRIBUTOR TO DISTRIBUTE SAID COMMINGLED MATERIAL TO BE MELTED AND SAID COMBUSTION AGENT IN SAID CUPOLA IN A CIRCULAR PATTERN SPACED OUTWARDLY FROM THE CENTER OF SAID CUPOLA, SAID CONTROL DEVICE COMPRISING A CONSTANT LEVEL CONTACT MEMBER IN SAID CUPOLA, AND MEANS FOR PERIODICALLY MOVING SAID CONTACT MEMBER GENERALLY IN A DIRECTION PARALLEL TO THE LONGITUDINAL AXIS OF SAID CUPOLA FROM A POSITION BENEATH THE EXPOSED THE SURFACE OF THE BURDEN OF CHARGED MATERIALS IN SAID CUPOLA TO A POSITION IN CONTACT WITH THE FREE EXPOSED SURFACE OF SAID BURDEN.

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