US2419079A

US2419079A - Sealing device

Info

Publication number: US2419079A
Application number: US566446A
Authority: US
Inventors: Jaxtheimer Charles Henry
Original assignee: Carnegie Illinois Steel Corp
Current assignee: Carnegie Illinois Steel Corp
Priority date: 1944-12-04
Filing date: 1944-12-04
Publication date: 1947-04-15
Anticipated expiration: 1964-04-15

Description

April 1947- c. JAXTHEIMER 2,419,079

' SEALING DEVICE Filed Dec. 4, 1944 2 Sheets-Sheet; 2

Wfi w "w M M w m 7 A 1 Hm Patented'Apr. 15, 1947 SEALING DEVICE Charles HenryJaxthelmer, North Braddock, Pa assignor to Carnegie-Illinois Steel Corporation, a corporation of New Jersey Application December 4, 1944, Serial No. 566,446

7 Claims. 1

This invention relates to an improved fluid'sealing means, more particularly to a fluid sealing means between relatively moving or rotating parts. The sealing device of the present invention has particularutility where such relatively mov-- ing parts are exposed to an atmosphere which itself tends to attack the packing of the sealing means, or which carries a material such as particles which attack and wear such packing and the parts cooperating therewith.

The invention has among'its objects the provision of an improved fluid sealing means wherein wear of the packing and cooperating parts by the atmosphere which it seals, or by a material or particles in such atmosphere, is minimized.

Another object of the invention is the provision of such seal which has a longer life and requires fewer adjustments than prior art seals used under the same conditions.

These and further objects of the invention will appear in the following disclosure.

It is frequently necessary in closures comprising one or more relatively movable or rotatable members to employ sealing means therebetween to make the closure at least substantially gas or liquid tight. In applications where the gas or liquid, either in or outside the closure, itself attacks the packing means or the parts cooperating therewith or carries a material or particles which attack or abrade such sealing means, the life of the seal has been relatively short and much attention is required during its life to maintain it in effective sealing condition. The present invention provides a sealing means which,overcomes such difficulties by preventing the seal deteriorating atmosphere from coming in contact therewith.

Whereas the invention is illustrated in connection with its use in a metallurgical blast furnace, in which it displays particular advantages, it is useful in other applications where atmospheres detrimental to the packing and parts cooperating therewith are encountered.

The invention will be more readily understood by reference to the accompanying drawings, in

which: t

Figure 1 is a schematic view of a portion of a metallurgical blast furnace in which the sealing means of the present invention is employed;

Figure 2 is a view in vertical cross section through the rotating hopper and seal of such blast furnace; Y

Figure 3 is a view in cross section taken along the line of III--III in Figure 2;

Figure 4 is an enlarged view in crosssection taken through the line IVIV in Figure 3; and Figure 5 is an' enlarged view in cross section taken through the line VV in Figure 3.

A portion of a typical blast furnace, in which the sealing means of the present invention may be employed, is shown in Figure 1, the top of the blast furnace shaft or stack being designated by the reference character 2. As is conventional, such blast furnace is charged by a skip car 3 with the requisite amount of iron ore, coke, and limestone to form the furnace burden. Skip car 3- discharges the material into the stationary receiving hopper 4, whence it travels downwardly into the small bell hopper 6, which is intermittently rotated to insure uniformity of charge distribution on the small bell 8, which normally closes the bottom end of hopper 6. Bell 8 may be lowered when desired to discharge the material thereon onto the large bell in which is normally maintained in upward position against the bottomof large bell hopper l2. The bottom of the rotating hopper 6 projects through the top of the gas seal hood or chamber l4, and is sealed thereto by gas seal means indicated generally in Figure 1 by reference character It. Since either the small bell or the large bell is maintained in upward sealing position at all times, that is, the large bell is up when the small bell is lowered and the small bell is up 'when the large bell is lowered, the top of the blast furnace is kept sealed from the atmosphere.

The gas sealing means It is subjected to the gaseous atmosphere within the upper part ofthe blast furnace. Such atmosphere is laden with fine particles, such as coke breeze, fine ore, and limestone. furnace exceeds atmospheric pressure, being normally about 1 lb. per square inch above atmospheric pressure, and, in the case of a slip, that is, when the furnace burden hangs on the furnace walls and then falls downwardly into a void space, reaching a value of 4 to 5 lbs. above atmospheric pressure, there is a pronounced tendency for the particles in the furnace atmosphere to work into thepacking of the sealing means. Such particles Since the pressure within the blast are abrasive incharacter and wear the packing and the part of the rotating hopper against which the packing bears to such an extent as to require frequent adjustments and tightening of the packing. The wear on such parts is so severe as to require changing the hopper two or three times during the furnace campaign, and adjusting and replacing the packing innumerable times during such period. Change of the packing or the rotating hopper requires fanning the furnace to virtually temporarily shut it down. Such practice thus results in a marked decrease in production.

The sealing means of the present invention incorporates therein means between the packing and the furnace or closure atmosphere to create a current of fluid which is relatively particlefree in a direction away from the packing means, whereby the particle-carrying atmosphere which would otherwise attack the sealing means is repelled from the packing. Asa result, the wear on the packing means and cooperating parts such as the rotating hopper is very much reduced, fewer adjustments of the sealing means are necessary, and the life of the packing and that of the cooperating parts of the sealing means are very much increased.

The structure of the sealing means by which this is accomplished is shown in Figures 2 to 5.

. 4 i 39 of the rotating hopper and forms a gas tight seal therewith.

The'bottom innerportion 38 of spider 32 is formed, as shown more clearly in Figures 4 and 5, with a plurality of spaced annular lands. or rings 56 closely surrounding but very slightly spaced from cooperating outer surface 33 of the rotating hopper. Between glands 56 the lower inner portion 38 of the spider is provided with parallel grooves 58 of substantialdepth. It is to be understood that whereas in the embodiment shown, there'are employed a plurality of lands and grooves, part 38 of the spider may, if desired, be provided with only one annular surface surrounding and slightly spaced from cooperating surface of the hopper and with one groove between such surface of the spider and the packing.

Groove-s 58 are supplied with a fluid under a pressure exceeding that of the atmosphere within the gas 'seal chamber by means of one or more supplypipes-fill connected to vertical passages As shown in Figure 2, the rotating hopper 6 of the furnace in which the sealing means is used is carried upon rollers l8 through the medium of ring member 20 attached to flange '22 projecting from the periphery of the hopper. The hopper is further guided by upper rollers 24, and-is rotated by means of ring gear 26, attached to the outer edge of member 20, which meshes with the drive pinion on a driving mechanism indicated generally at 28. The lower end of the rotating hopper projects through the upper end of the gas seal chamber l4, said chamber having a vertical upper portion parallel to the hopper 6. The sealing means of the present invention consists of an annular spider 32 aflixed to the upper portion of the gas seal chamber H by meansof flange 34 projecting outwardly on the spider, said flange resting upon and being secured to flange 33 on part 36 of the gas seal chamber.

Spider 32 consists of a bottom inner portion 38, the inner surface of which surrounds and is very slightly spaced from the outer cylindrical surface 39 of the rotating hopper 6. An u per angular outwardly directed portion 40 of the spider forms a part of a packing receiving pocket and an annular vertical wall portion 42, con-'- nected to portion 40 and spaced a substantial distance from outer surface 33 of the hopper, forms another portion of the packing receiving pocket. On top of the vertical wall portion 42 there is an outwardly directed horizontal flange 44. Packing 46, which may be made of flax impregnated with graphite and castor oil, is located in the pocket formed by

portions

40 and 42 of the spider, and is held tightly in the pocket and against surface 39 of the hopper by means of gland", which has a vertical sleeve portion 50 with its bottom face bevelled in a direction opposite from the direction in which angular portion 40 of the spider is inclined, as shown. Gland 48 is provided with an outwardly directed horizontal flange portion 52; bolts 54 running through holes in

flanges

44 and 52 pull the gland down tightly against the packing. By reason of I the angularities of portion 40 andthe bottom face of the sleeve portion 50 of the gland the packing is thrust inwardly against outer surface ward explosion of such furnace gases.

62 in the spider in a position behind grooves 58, passages 62 communicating with the grooves 58 by means of holes 64, as shown in Figure 5. Passages 62 may be formedin portion 38 of the spider by means of a suitable core if the spider is cast, or alternatively, by a plurality of consupply grooves 58 with steam, since steam is ideal a in that it does. not possess any marked deteriorating effects upon the packing and rotating hopper, and because it possesses the further advantage of diluting the furnace gases in the gas seal chamber and the furnace top as it trickles into the chamber through the very small spaces between the lands 56 and the outer surface 39 of the hopper, and thence into the top of the blast furnace, thereby suppressing any tendencies to- It is to be understood, however, that any gas or fluid not adversely effecting the operation of the particular apparatus in which the seal is employed and not having undesirable deteriorating effects upon' the packing, the spider, or the parts cooperating therewith, such as the hopper, may be employed. The presence of such fluid in the grooves of the spider forms an efiective barrier against the travel of the atmosphere in the closure into contact with the packing. This is due to the fact, that, since the land or lands of the spider are spaced slightly from the inner movable element, there is provided a passage through from the packing, since the fluid pressure in the grooves exceeds that in the furnace or other closure. .Fluid travel between part 38 of the SP1- which the fluid may travel in a direction away means between the .two members, a sleeve-like member attached to the outer member and having at least one continuous land on its inner surface closely surrounding but slightly spaced from the-inner member and between the packing means and the particle carrying fluid, said sleevelike member having a continuous groove of substantial depth between the land and the packing means, and means to introduce into such groove at a pressure exceeding that oi the particle laden fluid a relatively particle free fluid, whereby a current of the latter fluid away from the packing means and through the space between the inner member and the land on the outer member is created torepel the particle laden fluid from the packing means.

2. In the combination comprising an inner cylindrical member, an outer member having an opening into which the inner member projects, the inner and outer members being rotatable relative to each other, said inner and. outer members constituting at least part of a closure and being exposed on one side to a particle carrying fluid, a fluid seal which comprises a packing particle free fluid, whereby a current of the latter fluid away from the packing means and into the gas seal chamber is created to repel the particle laden gas in the gas seal chamber from the packing means.

5. In a metallurgical blast furnace comprising a gas seal chamber, a rotating bell hopper, the bottom of the bell hopper projecting through an opening in the gas seal chamber, a gas seal which comprises a packing means between the hopper and the gas seal chamber, a sleeve-like member attached to the gas seal chamber and having a plurality of spaced annular lands closely surrounding but slightly spaced from the bell hopper at a location close to the packing means and between the packing means and the interior of the gas seal chamber, said sleeve-like member having continuous grooves of substantial depth between adjacent lands, and means communicating with the grooves to introduce into them at a pressure exceeding that of the gas in the gas seal chamber a relatively particle free fluid, whereby a current of the latter fluid away from the packing means and into the gas seal chamber is created to repel the particle laden gas in the gas seal chamberfrom the packing means.

6. In a metallurgical blast furnace comprising a gas seal chamber and a rotating bell hopper,

means between the two members, a sleeve-like member attached to the. outer member andhaving a plurality of continuous, annular, lands on its inner surface closely surrounding but slightly spaced from the inner member and between the packing means and the particle carrying fluid, said lands being separated by grooves of substantial depth, and means to introduce into the grooves at a pressure exceeding that of the par:

ticle laden fluid a relatively particle free fluid, whereby a current of the latter fluid away from the packing means and through the space between the inner member and the lands on the outer member is created to repel the particle laden fluid from the packing means.

3. In a metallurgical blast furnace comprising a gas seal chamber, a rotating bell hopper, the bottom of the bell hopper projecting through an opening in the gas seal chamber, a gas seal which comprises a, packing means between the hopper and the gas seal chamber, and a passage located adjacent the packing and between it and the inner space of the gas seal chamber to which. is supplied a current of a relatively particle free fluid along the bell hopper and away from the packing to repel the particle laden gas in the gas seal chamber from the packing.

4. In a metallurgical blast furnace comprising a gas seal chamber, a rotating bell hopper, the

bottom of the bell hopper projecting through an opening in the gas seal chamber, a gas seal which comprises a packing means between the hopper and the gas seal'chamber, a sleeve-like member attached to the gas seal chamber and having at least one annular land closely surrounding but slightly spaced from the bell hopper at a location close to the packing means and between the packing means and the interior of the gas seal chamber, said sleeve-like member having a continuous groove of-substantialdepth between the land and the packing means, and means to intro duce into said groove at a pressure exceeding that of the gas in the gas seal-chamber a relatively the bottom of the bell hopper projecting through an openingin the gas seal chamber, a gas seal which comprises an integral spider constituting the portion of the gas seal chamber which confronts the bell hopper, said spider cbmprising a sleeve-like portion surrounding and spaced radially from the bell hopper to form a packing receiving pocket therebetween, a packing in said -pocket, means to retain the packing against the bell hopper and the sleeve-like portion of the spider, said spider having a further portion adjacent the packing and between the packing and the interior of the gas seal chamber in the form of a sleeve having a plurality of spaced annular packing means, said sleeve having continuousgrooves of substantial depth between adjacent lands, and means communicating with the grooves to introduce into them steam at a pressure exceeding that of the gas in the gas seal chamber; whereby a current of steam away from the packing means and into the gas seal chamber is created to repel the particle laden gas in the gas seal chamber from the packing means.

'7. In the combination comprising an inner cylindrical member, an outer member having an opening into which the inner member projects, the inner and outer members being rotatable relative to each other, said inner and outer members constituting at least part of a closure which is exposed on one side to a particle carrying fluid,

a fluid seal which comprises an integral spider constituting the portion of the outer member which confronts the inner member, said spider comprising a sleeve-like portion surrounding and spaced radially from the inner member to form a packing receiving pocket therebetween, a, packing in said pocket and means to retain the packing against the inner member and the sleeve-like portion of the spider, said spider having a further portion adjacent .the packing and between the .packing and the particle laden atmosphere in the form of a wall surrounding the inner member, said wall having a plurality of continuous annular lands on its inner surface closely surrounding butslightly spaced from the inner 7 member, said lands being separated by grooves of substantial depth, and means to introduce into the grooves at a. pressure exceeding that 01' the particle laden fluid a relatively particlefree fluid,

whereby a current of the latter fluid away from- 5 the packing means and through the space between the inner member and the lands on the outer member is created .to repel the particleladen fluid from the packing means.

CHARLES HENRY J AXTHEIMER.

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

Number 910,233 1,865,476 1,056,282 2,319,543

Number