US3275310A

US3275310A - Blast furnace bell

Info

Publication number: US3275310A
Application number: US327925A
Authority: US
Inventors: Ralph T Hanna
Original assignee: United States Steel Corp
Current assignee: United States Steel Corp
Priority date: 1963-12-04
Filing date: 1963-12-04
Publication date: 1966-09-27
Anticipated expiration: 1983-09-27

Description

Sept. 27, 1966 R. T. HANNA BLAST FURNACE BELL 2 Sheets-Sheet l Filed Dec.

l/VVENTOR. RALPH 7: HAN/VA Attorney Sept. 27, 1966 R. T. HANNA BLAST FURNACE BELL 2 Sheets-Sheet 2 Filed Dec.

INVENTOR. RALPH 7. HANNA W Arforney United States Patent 3,275,310 BLAST FURNACE BELL Ralph T. Hanna, Yardley, Pa., assignor to United States Steel Corporation, a corporation of Delaware Filed Dec. 4, 1963, Ser. No. 327,925 2 Claims. (Cl. 266-27) This invention relates to a blast furnace bell and more particularly to the small bell for an iron producing blast furnace. In order to charge the blast furnace, the .top of the furnace is provided with a double bell arrangement having an upper or small bell which provides a seal between .a revolving hopper and the lower ball hopper. In charging, the materials are dumped by a skip onto the small bell after which the small bell is moved downward- 1y to drop the material onto the large bell. Afiter a number of skip loads the large bell is opened and the small bell held closed and the material dropped into the furnace. When the large bell is in its lower or open position the small bell must provide a tight seal between the pressure of the furnace and the atmosphere. Since the materials of the charge are highly abrasive the small bell wears rapidly as the material slides over its outer surface. After a period of between 12 and 18 months the sealing surface of the small bell is worn to such an extent that the bell must be replaced. The rod sup porting the large bell passes through the hollow rod which supports the small bell so that the small bell is made in two pieces with the two halves split in a vertical plane. A wearing apron is generally provided around the top of the small bell and the bottom of its rod and wearing rings are provided above the wearing apron around the small bell rod. In order to replace the bell, the wearing rings and apron are raised to clear the bell and the bolts holding the two halves of the bell together are unbolted from beneath. The bell is then removed from the rod and dropped down into the space between the bells where they are removed from the furnace through a man hole. Because of the diflicult working conditions and because the wearing rings and apron tend to stick together so that they are difficult to raise, it is necessary to shut the furnace down for a period of between 16 to 24 hours each time the bell is replaced.

It is therefore an object of my invention to provide a small hell that is so constructed that only a portion thereof need be replaced.

Another object is to provide such a bell which is so constructed that the time necessary to renew it is greatly reduced.

These and other objects will be more apparent after referring to the following specification and attached drawings, in which:

FIGURE 1 is an elevation, partly in section, showing the small bell of my invention in place on a blast furnace;

FIGURE 2 is an elevation showing one half of the bell of my invention; and

FIGURE 3 is a view taken on the line IIIIII of FIG- URE 2.

Referring more particularly to the drawings, reference numeral 2 indicates a hopper having a peripheral conical seat 4 at the lower end thereof, A hollow rod 6 extends downwardly through the hopper 2 and has a small bell =8 attached thereto in the usual manner. The top of the rod 6 is supported by support assembly 10 which is attached to the usual lifting mechanism 11, only a part of which is shown. A large bell rod 12 extends downwardly through hollow rod 6 to the large bell, not shown. A wearing apron 14 surrounds the top of the bell 8 and the bott-omof the rod 6. Wearing rings 16 are provided around the rod 6 above the apron 14. The parts so far Patented Sept. 27, 1966 "ice described, except for the construction of bell 8, are conventional.

According to my invention the hell 8 is made up of four generally hollow

conical sections

18, 20, 22 and 24. The

upper sections

18 and 20 each has an inwardly extending generally vertical flange 26 on each end with matching aligned holes therein so that they can be fastened together by means of bolts 28. A vertical shoulder 30 is provided around the lower outside periphery of the

sections

18 and 20. The

lower sections

22 and 24 each has an inwardly extending horizontal flange 32 at the top thereof and the

upper sections

18 and 20 each has -a corresponding horizontal flange 34 at its lower end which abuts the flanges 32. Aligned holes are provided in the flanges '32 and 34 for receiving bolts 36. The

sections

22 and 24 each has an inwardly extending vertical flange 38 at each end having aligned holes 40 therein for receivin bolts 42.

A generally conical sealing surface 44 is provided around the periphery of the

sections

22 and 24 for engagement with the seat 4.

When the sealing surfaces 44 become worn to such an extent that excessive gas leakage occurs, the furnace is shut down with the large bell closing the top thereof below the small hell 8. The workmen enter the space between the bells through a man hole, not shown, and remove the

bolts

36 and 42 thus separating the

sections

22 and 24 from each other and from

sections

18 and 20. Since the

sections

22 and 24 are relatively small they need not be removed but can be placed on the large bell and later dumped into the blast furnace.

New sections

22 and 24 are then assembled together and to the

sections

18 and 20 by means of

bolts

36 and 42. I have found that this replacement can be accomplished much faster than the replacement of the bells previously used so that the down time of the furnace is about 6 hours. If desired the

upper sections

18 and 20 can be made thicker than usual without their weight being increased to such an extent that they cannot be readily handled. This permits elimination of the wearing apron. By providing the shoulder 30 less wear occurs on the sealing surfaces 44 since the material sliding down over the bell will tend to slide from the outer surfaces of the

sections

18 and 20 directly to the large bell hopper.

While one embodiment of my invention has been shown and described, it will be apparent that other adaptations and modifications may be made without departing from the scope of the following claims:

I claim:

1. In a blast furnace, the combination including a hopper having a peripheral conical seat at its lower end, a generally conical bell within said hopper and extending below the bottom thereof, and means for raising and lowering said bell; said bell comprising two upper sections having a generally conical outer surface, a generally vertical flange on each end of each upper section, the flanges on each section having holes therein aligned with the holes in the adjacent flange of the other section, means in said aligned holes detachably fastening the two sections together, two lower sections having a generally conical outer sealing surface adapted to engage said peripheral conical seat, a generally vertical flange on each end of each lower section, the flanges on each lower section having holes therein aligned with the holes in the adjacent flange of the other lower section, means in said last named aligned holes detachably fastening the lower sections together, each of said upper sections having an inwardly extending peripheral flange .at the bottom thereof, each of said lower sections having an inwardly extending peripheral flange at the top thereof, said horizontal flanges having holes therein, the holes in the horizontal flanges of the upper sections being aligned with 3 4 the holes in the horizontal flanges of the lower sections, References Cited by the Examiner glsdeggeanihin said listdnameed aligtngdsh tcglggt 1ileltaeh'a-bly UNITED STATES PATENTS ng-eupper n owrsecin 2. The combination of claim 1 in which [the outer sur- 2,429,481 10/1947 Mohr et 266-47 face of the bell includes .a uniform diameter portion ad- 5 jacent the junction between the upper and lower section-s JOHN CAMPBELL P'lmary Examiner with the maximum diameter of the joined upper sections M. L. FAIGUS, Assistanl Examiner.

and the minimum diameter of the joined lower sections being equal to said uniform diameter portion.

Claims

1. IN A BLAST FURNACE, THE COMBINATION INCLUDING A HOPPER HAVING A PERIPHERAL CONICAL SEAT AT ITS LOWER END, A GENERALLY CONICAL BELL WITHIN SAID HOPPER AND EXTENDING BELOW THE BOTTOM THEREOF, AND MEANS FOR RAISING AND LOWERING SAID BELL; SAID BELL COMPRISING TWO UPPER SECTIONS HAVING A GENERALLY CONICAL OUTER SURFACE, A GENERALLY VERTICAL FLANGE ON EACH END OF EACH UPPER SECTION, THE FLANGES ON EACH SECTION HAVING HOLES THEREIN ALIGNED WITH THE HOLES IN THE ADJACENT FLANGE OF THE OTHER SECTION, MEANS IN SAID ALIGNED HOLES DETACHABLY FASTENING THE TWO SECTIONS TOGETHER, TWO LOWER SECTIONS HAVING A GENERALLY CONICAL OUTER SEALING SURFACE ADAPTED TO ENGAGE SAID PERIPHERAL CONICAL SEAT, A GENERALLY VERTICAL FLANGE ON EACH END OF EACH LOWER SECTION, THE FLANGES ON EACH LOWER SECTION HAVING HOLES THEREIN ALIGNED WITH THE HOLES IN THE ADJACENT FLANGE OF THE OTHER LOWER SECTION, MEANS IN SAID LAST NAMED ALIGNED HOLES DETACHABLY FASTENING THE LOWER SECTIONS TOGETHER, EACH OF SAID UPPER SECTIONS HAVING AN INWARDLY EXTENDING PERIPHERAL FLANGE AT THE BOTTOM THEREOF, EACH OF SAID LOWER SECTIONS HAVING AN INWARDLY EXTENDING PERIPHERAL FLANGE AT THE TOP THEREOF, SAID HORIZONTAL FLANGES HAVING HOLES THEREIN, THE HOLES IN THE HORIZONTAL FLANGES OF THE UPPER SECTIONS BEING ALIGNED WITH THE HOLES IN THE HORIZONTAL FLANGES OF THE LOWER SECTIONS, AND MEANS IN SAID LAST NAMED ALIGNED HOLES DETACHABLY FASTENING THE UPPER AND LOWER SECTIONS TOGETHER.