US2632658A - Sealing ring for rotary kilns - Google Patents

Description

March 24, 1953 F; A. MERTZ 2,632,658

SEALING RING FOR ROTARY KILNS Filed Dec. 50, 1948 2 SHEETS-QSHEET 1 awe/Mom li'eclA.Meriz March 24, 1953 v A. MER 2,632,658

SEALING RING FOR ROTARY KILNS Filed Dec. 30, 1948 2 SHEETS-SHEET 2 mum a;

Patented Mar. 24, 1953 UNITED STATES PATENT OFFICE Fred A. Mertz,Allentown, Pa., a'ssignor to Traylor Engineering & Manufacturing Company, Ailentown, Pa., a corporation of Delaware Application December 30,.1948,:SerialN1o. 68,320

Claims. 1 The invention of the present application is a modification of and improvement upon the seal ing means shown, described, and claimed in my copending application Serial No. 706,439, filed October 29, 1946, entitled Sealing Ring for Rotary Kilnnow Patent No. 2,461,754, February 15, 1949. Y

As was the, case with the invention of that application, the present invention relates to rotary kilns of the type used in the manufacture of Portland cement and the like. More particularly, the invention is concerned with improvements in the sealing means between the end of a rotary kiln and the normally stationary firing hood, positioned adjacent thereto.

In the past, various types of seals have been provided between the ends of rotary kilns and the adjacent firing hoods, but numerous difiiculties and disadvantages have been encountered in their use. One of the most generally used constructions consists of a pair of flanged rings carried by the kilnand hood respectively, making a substantially running contact or spaced apart a predetermined "distance, for theadmission of currents of atmospheric air, tending to maintain the end of the kiln shell at reasonably cool temperatures, to prevent overheating and burning out of the same. In such constructions however, it has been necessary to advance --andretra ct the firing hood with respect to'the rotary kiln, to compensate for axial expansion and contraction of the latter under the .infiuence of temperature changes. Even though the firing hood be mounted on track supported wheels, the adjustment of the hood and its associated parts is a laborious and troublesomeoperation. Moreover, d-ifiiculty is encountered in maintaining the space between the fixed and vrotatable rings constant during the operation of the apparatus, and nicety of adjustment in this connection has been difiicult or impossible to accomplish.

One of the primary objects of the present invention is to overcome the difiiculties encountered in the use of prior art seals between the ends of rotary-kilns and the adjacent stationary firing .hood.

a seal for the end of :a rotarykiln and associated 2 firing hood. A further object is to provide a construction in which the space between thest-ationary and rotatable parts will not vary during the operation of the apparatus, in the event of expansion or contraction of the kiln, resulting from temperature changes.

Another object of the invention is to provide a seal of the type described in which the parts are constantly maintained in -the desired, closely fitting relation by the influence of gravity, working on one part and tending to move the same toward the other.

A further object is to provide long lasting, efiieient, anti-friction connections between the fixed and movable parts, thereby reducing wear and other adverse factors.

Another object of the invention .is to provide an improved seal, in which one sealing ring is non-rotatably supported by an enclosure, such as a firing hood or stack .base, with capability of limited axial movement relative thereto, and in which a second, rotatable ring, encircling the end of the kiln and rigidly secured in gas-tight relation thereto, is disposed in sealing relation thereto.

Another object of the invention to provide a seal comprising a radially projecting ring secured to the kiln for axial movement therewith, upon expansion and contraction of the kiln, and an axially movable, non-rotatable ring, disposed in sealing relation with respect to the first ring and having a gas-tight connection withtheadjacent firing hood or other enclosure.

Another object of the invention is .to provide a .seal comprising a pair of sealing rings, one of which is rotatable and the other of which is stationary, in which anti-friction rollers are carried by the non-rotatable ring, and in which conduits for lubricating material deliver lubricant thereto from an external,fixed source.

Other and further objects and advantages of the invention will be apparent from the following description of a preferred embodiment, shown in the accompanying drawings, in which:

Figure 1 is aside elevation, with certain parts in section, of the lower endtof ,a rotary j'kiln and an associatedfiring hood, having the improved seal incorporated therein;

Figure 2 is a section on line .2--2 of Figure 1;

Figure 3 is an enlarged section, taken on line 3--3 of Figurez, and

Figure 4 is an enlarged elevation taken substantially-on line 4-4 of Figure 2.

A rotary kiln having a metallicshell it may be supported for rotation about its longitudinal 3 axis, in inclined relation to th horizontal axis, by suitable means, well understood in the ar and therefore not shown in the accompanying drawings. A kiln of this type is conventionally lined with refractory brick work, not shown, and has its lower ends ll projected into the open forward end [2 of a firing hood IS. The latter may be mounted upon wheels, for longitudinal movement toward and away from the kiln, as explained in the above mentioned application. Secured to the forward end of the shell of the firing hood, surrounding the circular openin therein, is a collar M, having an inwardly extending flange l5 and a cylindrical flange ll, of downwardly increasing length, as indicated at l8, so that its forward edge is disposed on a plane perpendicular to the axis of the kiln ill.

The firing hood shell I3 carried a pair of brackets 59 and 20, having forwardly projecting arms 2| and 22, the upper surfaces of which are parallel to the axis of the rotary kiln and carry tracks 23, 24. A ring casting having a cylindrical flange 2t and a radial flan 2! has formed integrally therewith a pair of diametrically projecting, hollow bosses 2e and 29, in which stub shafts are disposed, supporting wheels 35 and 3E, riding on tracks 23 and 25, so that the ring casting as a whole is capable of limited longitudinal movement relative to the Collar 14.

Encircling the flange ll of the 11ar M is a rod 32, welded in place, and a similar rod 33 is similarly secured to the rear portion of the cylindrical flange 26 of ring casting 25. An annular strip 34 of flexible heat resisting material has its inner edge portion seated against the rod 32 and clamped upon the periphery of the flange ll by a clamping wire 35. The outer edge of the flexible strip 34 is secured in gastight relation to the outer edge of a similar, inwardly projecting, annular strip 35 of flexible, heat-resisting material. The inner edge of the latter strip, likewise, is seated against the rod 33 and is clamped upon the periphery of the flange 26 of ring casting 25 by a clamping wire Thus, the strips 34 and 36 constitute a gastight seal between the collar I 4 and the ring casting 25, but permit axial movement of the ring casting relative to the hood. The strips may be made of thin flexible metal, but preferably are of asbestos cloth having a wire mesh inner layer.

A sectional ring casting 5i], encircling the lower end of the kiln shell I0, having a plurality of terminal webs ll, by which the sections are interconnected, is welded to the shell, as indicated "at 32 and 63 in Figure 3. The ring casting 49 carries a circumferentially continuous, forwardly facing, sealing rin A l, for rotation with the kiln, while the flange 2'! of the non-rotatable ring casting 25 carries a rearwardly facing sealing ring 53 in juxtaposed relation thereto.

The outer or forward face of the radial flange 2'! of the non-rotatable ring casting 25 is provided with a plurality of pairs of forwardly projecting blocks 45, 46, having arcuate seats therein for the reception of the reduced ends 4'! of stub shafts, having eccentric body portions 48, upon which rollers 49 are journalled. The shafts may be secured in angularly adjusted relation by caps 50 and 5|, as explained in the above mentioned application, to adjust the degree of projection of rollers 49 through the ad jacent slots 52 and 55 in the flange 27 and ring 4 53, to control the spacing between the rings 4 and 53, and the amount of atmospheric air permitted to flow into the lower end of th kiln, for cooling purposes, as described above.

The shell E3 of the firing hood carries a plurality of forwardly projecting brackets 60, GI, 62, and 83, each of which comprises a pair of inwardly projecting, spaced apart legs 6e and 65 and a forwardly projecting arm 66, to the ward end of which is pivoted a, bell crank lever 61, by a fulcrum pin 68. The two upper bell crank levers each comprise a forwardly projecting horizontal arm 69, having a weight 19 mounted upon its free end, and a downwardly projecting, substantially vertical arm H, having a rounded head 12 disposed Within a socketed seat 13, formed integrally upon the forward face of the flange 21 of ring casting 25. The two lower bell crank levers (Figure 1), each comprises a rearwardly projecting horizontal arm 15, having a weight it on its rear end and an upwardly projecting, substantially vertical arm Tl, having its upper end similarly disposed in one of the seats 13. Thus, the bell cranks tend to urge the rin casting 25 and the parts carried thereby, rearwardly, toward the firing hood it, this movement being permitted by the rin supporting wheels 35 and 3| riding upon the tracks 23 and 24. Rearward movement of the non-rotatable ring is restrained by the engagement of the rollers 59 with the forward face of the rotatable ring 45, carried by the kiln shell. As the kiln expands and contracts, axially, the ring casting 25 follows the movements thereof, thereby maintaining the desired seal at all times.

The weights 1!] and 16, carried by the arms 69 and 15 of the upper and lower bell cranks are mounted thereon for longitudinal adjustment along the arms, to vary the effective force applied by the levers to the nonrotatable ring 53. Under certain conditions, it is desirable to have the rollers 49 so adjusted that the nonrotatable ring 53 and the rotatable ring 44 make sliding, face to face contact, to eliminate the introduction of air into the lower end of the kiln and, in such cases the friction between the rings may be reduced by moving the weights nearer to the fulcrums of the levers and thereby reducing the applied pressure. It will be understood therefore that the introduction of air may be varied from substantially none to the maximum permitted by the eccentricity of the bodies '48 of shafts 41, with the rollers 49 projected the maximum amount, through the slots in the non-rotatable ring 53.

Each of the eccentric shafts 48 carries on its radially outer end 41 a lubricant fitting 80, by which lubricant may be delivered, through internal passages, not shown, to the bearing for the roller 49. Each fitting is in communication with one of the conduits Ill-89, leading to a bracket 95, carried by the flange 2'! of the ring casting 25. The several conduits 8l89 are connected at this point to flexible hoses 9|99, connected at their other ends to a header block I00 and by suitable means to a source of lubricant. Thus, lubricant may be delivered from time to time, or continuously, to the several rollers 49, while the apparatus is in operation, yet the ring casting 25 is free to move axially upon expansion and contraction of the kiln.

It should be understood that the above described lubricating system'is not an essential of the invention, as sealed bearings for the rollers a esaess maybe employed :and the conduits and fittings eliminated.

Although the invention has'been described with considerable particularity "in the foregoing specification, itmust be understood that the invention isnot limitedto the details of construction shown in the accompanying drawings and described above;but includesallmodifications coming'within the scope "of the appended claims and their equivalents.

l. A-sea-ling connection for the end-of a rotary cylindrical kiln and anadjacent, stationary =casing having a circular collar mounted thereon in gas-tight relation and into which said end projectsjsaid connection comprising a non-rotatable ring relatively closely encircling said endof the kiln in spaced relation to said collar and said end and having asubstantially radially disposed sealing surface, means supporting the ring from the casing for limited axial movement with respect to the collar, but restraining thering against rotation, a flexible gas-tight seal between said ring and said collar, a second ring having a substantially radially disposed sealing surface facing said surface of the first ring and disposed in substantially gas-tight sealing relation with respect thereto, said second ring encircling said --end of the kilnandsecured in'gas-tight relation thereto for'rotation therewith, means for urging the first ring 'axiallytoward-the second, to maintain the substantially gas-tight sealing relation between 'the'two, and a plurality of radially disposed rollers'carried by the first ring making rolling contact with the adjacent surfaceof the second ring.

2. A sealing connection for the discharge end of a rotary, cylindrical kiln and an adjacent, normally stationar firing hood having an opening bounded by a circular collar into which said end of the kiln projects, comprising a non-rotatable ring encircling said end of the kiln and supported by the hood in forwardly spaced relation to said collar for limited axial movement with respect thereto and having a substantially radially disposed sealing surface, a flexible gas-tight seal between said ring and said collar, a second ring having a substantially radially disposed sealing surface facing said surface of the first ring and disposed in substantially gas-tight sealing relation with respect thereto, said second ring encircling said end of the kiln and rigidly secured in gas-tight relation thereto in the space between the collar and the first mentioned ring for rotation with the kiln, means for urging the first ring toward the second, and a plurality of circumferentially spaced, radially journalled rollers carried by the first ring, making rolling contact with the adjacent surface of the second ring.

3. An apparatus in accordance with claim 2 in which the means for urging the first ring toward the second comprises a plurality of brackets carried by the hood, projecting forwardly beyond the first ring, a bell crank pivoted to the forward end of each bracket having a substantially vertical arm bearing against the forward face of the first ring and a horizontally extending, weighted arm urging the first mentioned arm in a direction to urge the ring against the second ring.

4. An apparatus in accordance with claim 2 in which the sealing means between the first mentioned ring and the hood comprise an outwardly projecting, flexible annular strip havin its inner margin operatively secured to the hood in gas-tight relation, an inwardly projecting flexible annular strip having its outer margin secured 6 to the outer margin of the first mentioned strip and its-inner marginsecured to said non-rotatable ring, whereby the ring may .move axially relative to the hood by flexing .of said annular strips.

5. A sealing connection forthe discharge end of a rotary cylindrical kiln and an adjacent normally stationary firing :hood of the type having a stationary circular opening into whichlsaid .end of the kiln project's, said connection comprising a collar surrounding said hood openingand proj ecting forwardly therefrom, a non-rotatable ring member supported by the hood for limited axial movement withrespect thereto, said ringmember having a radial flange encircling the :lower end of the kiln with its inner margin in spacedrelation thereto and a cylindrical, rearwardly'projecting flange disposed in concentric spaced:r.elation to said collar, a flexible seal between the collar and said cylindrical flange, a second gring encircling saidend of thekiln and rigidlysecured thereto in gas-tight relation for rotation there-- with, said ring being disposed between the radial flange of the first mentioned ring member and the collar, a plurality of radially journalled rollerscarried by'the radial flange of said ring :member, making rolling contact with the second ring, and means for urgingthe ring member rearwardly toward the second-ring.

6. A sealing connection for the discharge-end of "a rotary cylindrical kiln and an adjacent normally stationary firing hood of the type having a stationary circular opening into which said end of the kiln projects, said connection comprising a collar surrounding said hood opening and projecting forwardly therefrom, a non-rotatable ring member supported by the hood for limited axial movement with respect thereto, said ring member having a radial flange encircling the lower end of the kiln with its inner margin in spaced relation thereto and a cylindrical, rearwardly projecting flange disposed in concentric spaced relation to said collar, a flexible seal between the collar and said cylindrical flange, comprising a pair of annular strips of gas impervious, flexible material secured together at their outer margins in angular relation and secured at their inner margins, respectively, to said collar and to the cylindrical flange of said ring member, a second ring encircling said end of the kiln and rigidly secured thereto in gas-tight relation for rotation therewith, said second ring being disposed between the radial flange of the first mentioned ring member and the collar, a plurality of radially journalled rollers carried by the radial flange of said ring member, making rolling contact with the second ring, and means for urging the ring member rearwardly toward the second ring.

7. A sealing connection for the discharge end of a rotary cylindrical kiln and an adjacent normally stationary firing hood of the type having a circular opening into which the end of the kiln projects, said connection comprising a collar surrounding the hood opening and having a forwardly projecting cylindrical flange, a ring member supported by the hood forwardly of the collar for limited axial movement with respect thereto but restrained against rotation, said member comprising a cylindrical flange encircling the fiange of the collar in concentric, spaced relation thereto, and a radially inwardly projecting flange at the forward end thereof, a flexible gas-tight seal between said cylindrical flanges, a radially outwardly projecting ring encircling said kiln and rigidly secured in gas-tight relation thereto for rotation therewith, said ring being positioned between the collar and the radial flange of said ring member and facing the latter, means urging the ring member toward the rotatable ring, and. a plurality of axially adjustable radially journalled rollers carried by the radial flange of the ring member, making rolling contact with the rotatable ring, whereby the space between the rotatable and non-rotatable elements may be varied by axial adjustment of said rollers.

8. A construction in accordance with claim 7 in which the radial flange of the ring member is slotted at circumferentially spaced points, in which the journals for the roller are carried by the forward face of the flange and in which the rollers project through said slots for engagement with the rotatable ring.

9. A sealing connection for the end of a rotary cylindrical kiln and an adjacent normally stationary easing into which the kiln projects, comprising a non-rotatable ring encircling said end of the kiln, supported by the hood in spaced relation thereto for limited axial movement with respect thereto, a gas-tight seal between the ring and the casing, a second rotatable ring projecting outwardly from the kiln in gas-tight relation thereto and disposed between the first ring and the casing, means for urging the first ring toward the second ring, a plurality of circumferentially spaced, radially journalled rollers, carried by the first ring making rolling contact with the second ring, and conduit means including flexible sections for delivering lubricant from a fixed, external source to each of said rollers.

10. A sealing connection for the discharg end of a rotary cylindrical kiln and an adjacent normally stationary firing hood, comprising a nonrotatable ring encircling said end of the kiln,

6 supported by the hood in forwardly spaced relation thereto for limited axial movement with respect thereto, said ring having a plurality of circumferentially spaced slots therein, a gastight seal between the ring and the hood, a second ring fixed to the kiln, projecting radially outwardly therefrom in gas-tight relation thereto and disposed between the first mentioned ring and the hood, means for urging the first mentioned ring rearwardly toward the second, a plurality of circumferentially spaced, radially journaller rollers carried by the forward face of the first ring, extending through the slots therein and making rolling contact with the second ring, and conduit means including flexible sections for delivering lubricant from a fixed external source to each of said rollers.

FRED A. MERTZ.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 692,371 Shaw Feb. 4, 1902 1,500,589 Lundberg July 8, 1924 1,795,297 Dirkes Mar. 10, 1931 2,063,368 La Rosa Dec. 8, 1936 2,113,047 French Apr. 5, 1938 2,148,501 Rasor Feb. 28, 1939 2,285,007 Brennan et al June 2, 1942 2,461,754 Mertz Feb. 5, 1949 2,469,078 Robison May 3, 1949 FOREIGN PATENTS Number Country Date 469,624 Great Britain July 29, 1937

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