US3851865A

US3851865A - Bottom clamp for obm vessels

Info

Publication number: US3851865A
Authority: US
Inventors: H Fisher
Original assignee: Pennsylvania Engineering Corp
Current assignee: Pennsylvania Engineering Corp
Priority date: 1973-07-16
Filing date: 1973-07-16
Publication date: 1974-12-03
Anticipated expiration: 1991-12-03
Also published as: HU169907B; AR201779A1; DE2434235A1; GB1454688A; IN142261B; SU535036A3; BR7405884D0; DD115696A5; AU7128974A; CS198147B2; ZA744518B; CA1032749A

Abstract

A clamping device for attaching a replaceable bottom assembly to a refractory lined metallurgical converter vessel having a plurality of quick release clamps spaced circumferentially around the bottom assembly. Each clamp includes a pivotal clamp link of bracket supports and mounted on the vessel and having a roller intermediate its ends for engaging a clamp plate mounted on the bottom. The clamp links are secured in position by a swing bar and wedges or nuts.

Description

[ Dec. 3, 1974 United States Patent 1191 Fisher BOTTOM CLAMP FOR OB M VESSELS Inventor: Howard M. Fisher, New Castle, Pa.

Primary Examiner-Gerald A. Dost Attorney, Agent, or FirmFred Wiviott; Ralph G. Hohenfeldt [22] Filed:

[57] ABSTRACT A clamping device for attaching a replaceable bottom assembly to a refractory lined metallurgical converter vessel having a plurality of quick release clam 266/35, 292/257 C2lc 5/48 266/35, 36 P; 292/257 [52] US. [51] Int.

spaced circumferentially around the bottom assem bly held of Each clamp includes a pivotal clamp link of bracket supports and mounted on the vessel and having a rol- [561- References Cited UNITED STATES PATENTS ler intermediate its ends for engaging a clamp plate mounted on the bottom. The clamp links are secured 266/36 P 292/257 Cogelja et 266/35 PATENTEL BEE 3:914

FIG.4

BOTTOM CLAMP FOR OBM VESSELS BACKGROUND OF THE INVENTION This invention relates to removable bottom assemblies for metallurgical process vessels and more particularly to quick release attachment means for securing such bottoms into position.

In one type of converter vessel which is employed for converting molten ferrous metal to steel, process gases such as oxygen is blown through the molten metal by means of tuyeres extending through the refractory bottom of the vessel. Because the vessel bottoms tend to wear faster than the remaining vessel refractory, such vessels are often provided removable bottom inserts. These removable bottoms normally include tuyeres mounted on an insert bottom plate and extend upwardly through the refractory bottom structure. The tuyeres of bottom blown vessels may also comprise concentric pipes which permit the simultaneous injection of oxygen through the center pipe and a hydrocarbon containing shielding fluid such as propane light oil or natural gas through the space between the pipes.

In spite of the use of shielding fluids, such tuyeres and their surrounding refractory linings are generally burned away at a rate faster than the refractory lining of the vessel itself. It is therefore often necessary to replace the vessel bottom several times during the life of the refractory lining of the vessel. This bottom replacement procedure is a fairly lengthy process during which time the relatively expensive vessel and its associated apparatus are idle.

OBJECTS OF THE INVENTION A primary object of the-invention is to provide a new and improved clamping device for the bottoms of metallurgical vessels.

A further object of the invention is to provide a quick release clamp for attaching bottom assemblies to metallurgical converter vessels.

It is another object of the invention to provide a quick release clamp device for metallurgical vessels which are capable of supporting relatively heavy bottom assemblies.

It is yet another object of the invention to provide a clamp device for metallurgical vessel bottoms which will not interfere with the piping used to supply gases and particulate entrained material to the gas injection tuyeres.

How these and other more specific objects of the invention are achieved will appear from time to time through the more detailed description of a preferred embodiment of the invention taken in conjunction with the drawings. Generally, however, the invention comprises placing a plurality of clamp devices disposed around the bottom and including a first clamping member mounted on a metallurgical converter vessel. A first bracket of each device is attached to the bottom one of the vessel or bottom and a second quick release clamp is mounted on the other of the vessel and bottom, and is releasably engageable with the first clamping member. A third clamping member is mounted on the first clamping member for releasably securing the second member in position.

DESCRIPTION OF THE DRAWINGS FIG. 1 is a fragmentary view of the bottom portion of a metallurgical converter vessel which has been equipped with clamping devices in accordance with the present inventions;

FIG. 2 is an enlarged view of a clamping assembly according to one embodiment of the invention;

FIG. 3 is a view taken along lines 33 of FIG. 2;

FIG. 4 is a view taken along lines 44 of FIG. 3; and

FIG. 5 illustrates an alternate embodiment of the invention.

DESCRIPTION OF PREFERRED EMBODIMENTS FIG. 1 schematically illustrates the bottom portion of a refractory lined converter vessel 10 shown to include a removable bottom assembly 11 having one or more tuyeres 12 extending therethrough. A plurality of clamping assemblies 13 are distributed around the bottom of the vessel 10 for clamping the bottom 11 thereto. The furnace 10 may include a steel shell 14 and a refractory lining 15 for containing a quantity of molten metal 16. The bottom portion only of furnace 10 is illustrated since such converter vessels are known to the art. The bottom assembly may include a refractory plug 18 which is suitably mounted on a bottom metallic support plate 19. A suitable opening is provided in the bottom of metallic shell 14 and refractory lining 15 for receiving the plug 18. Plug 18 may be sealed within circular hole 17 by applying a quantity of refractory ramming mix or tar dolomite to the gap between plug 18 and opening 19. The particular shape of the vessel 10 and the bottom 11 are not critical, and they may have any convenient configuration. In addition, refractory plug 18 may be fabricated from a plurality of shaped refractories, or may be a cast or rammed member or any combination thereof.

While only a single tuyere is shown in FIG. 1 it will be appreciated that any suitable number may be employed, with the placement of the tuyeres in plug 18 being a matter of design choice. Tuyere 12 may be of any well known type and for example may consist of two concentrically arranged pipes with the inner' pipe 22 and the outer pipe 24 defining a fluid flow passageway 23 therebetween. In one exemplarymetallurgical refining operation, pipe 22 supplies oxygen or an oxygen containing gas to molten metal 16 and receives its supply of such gas from feed pipe 26. A hydrocarbon shielding fluid such as propane, natural gas, or light oil may be provided in a surrounding relation to the oxygen through the flow passage 23 which is coupled to feed pipe 27. In the event of a plurality of tuyeres, suitable manifolds and headers (not shown) are preferably provided for

coupling supply pipes

26 and 27 to the appropriate fluid passages of each tuyere. A cover 28 may be provided over the gas distribution system.

The reaction of the shielding fluid with the hot metal causes an endothermic cracking reaction which serves to protect and cool the tuyere and surrounding refractory from the heat resulting from the oxygen reactions in the melt. In addition, finely divided material, such as lime, may be entrained in the oxygen gas as dictated by process requirements. Also, argon, nitrogen, or other gases may be supplied through

pipes

26 and 27 during various portions of the processing cycle such as vessel turn-up or turn-down or during desulphurization or recarburization.

The clamping assemblies 13 may each be identical and accordingly only one such assembly will be discussed for the sake of brevity. According to one embodiment of the invention, the clamping assemblies 13 are shown in FIGS. 2-4 to include a first clamping link pivotally mounted on the metallic vessel shell 11 adjacent plate 19 and having a roller 36 for engaging a cam bracket 38 mounted on bottom plate 19. In addition, clamping assembly 13 includes a swing bar 40 pivotally mounted on plate 19 and about an axis generally parallel to the pivotal axis of clamp link 35 for swinging movement into parallelism with links 35 and adapted to receive a wedge member 41 which is engageable with member 35 to hold roller 36 in high pressure engagement with cam bracket 38.

Swing clamp 37 may include a pair of

parallel links

42 and 43 which are pivotally mounted on the opposite sides of a relatively flat bracket plate 45 which is suitably affixed in an edgewise manner to the lower end of the metallic vessel shell 11 and extending in a direction generally radial to the axis of the vessel 10. The ends of

links

42 and 43 embrace the opposite sides of bracket plate 45 and are pivotally mounted thereto by means of a bolt 47 extending through suitably aligned openings in

links

43 and 42 in bracket 45 and which is secured at its opposite end by a nut 49. The roller 36 is journaled for rotation intermediate the ends of

links

42 and 43 in about an axis parallel to the pivotal axis of said links by means of a bolt 50 extending through suitably aligned openings in

links

42 and 43 and roller 36 and which is secured by means of a nut 51.

Bracket 38 is suitably affixed to the metallic bottom plate 19 and is generally coplanar with bracket 45 upon which the clamp link assembly 35 pivots. As seen particularly in FIG. 2 a cam surface 52 is formed on the side of bracket plate 38 away from bracket plate 4i and at a distance from the pivotal axis of clamp links 35 which is lesser at its outer edge 53 and greater at its inner edge 54 than the distance from said pivotal axis to the periphery of roller 36. It will be appreciated, therefore, that as links 35 pivot counter clockwise as viewed in FIG. 2 the roller 36 will be moved into high pressure clamping engagement with the cam surface 52. Because of the

bracket members

45 and 38 are substantially coplanar and because of the location of cam surface 52 relative to roller 36, when the clamp link assembly 35 is pivoted counterclockwise as viewed in FIG. 2 the

links

38 and 43 will straddle cam bracket 42 and roller 36 will move into engagement with cam surface 52.

As seen particularly in FIGS. 2 and 4. the swing clamp 40 is pivotally mounted between a pair of spaced apart bracket plates 55 which are suitably affixed to the plate 19 in general parallelism with

brackets

38 and 45 by means of a bolt 56 which extends through suitable aligned openings in bracket plates 55 and one end of swing clamp 40. This positions swing clamp 40 generally is the plane of cam bracket 38. A longitudinal slot 58 is formed in the free end of swing member 40 and lies generally in the plane of cam bracket 38. When clamp links 35 are pivoted to engage roller 36 with cam surface 52, swing bar 40 extends through the gap between

links

42 and 43 with slot 58 on the side of said links opposite the pivot bolt 47. A tapered wedge 60 is adapted to be received within slot 58 for bearing against the edges of

links

42 and 43. It will be appreciated that the smaller dimensional end of wedge 60 will be less than the length of slot 58 so that movement of said wedge into the slot will urge the links 35 to pivotal movement in a counterclockwise direction to increase the clamping pressure between roller 36 and cam bracket 38.

When the bottom assembly 11 is to be mounted within the opening 17 in the refractory 15 of vessel 10, it will first be elevated into position by a suitable lifting mechanism (not shown 1. Each of the clamp links 35 of each clamping assembly 13 will be pivoted into engagement with its respective cam bracket 38 with the roller being forced as far as possible along surface 52. The individual wedges 41 will then be driven into their re spective slots 58 to increase the high pressure clamping engagement. When the bottom assembly 11 is to be removed from vessel 10, the procedure is reversed. More specifically, a bottom support assembly will be posi tioned in supporting engagement with the bottom I1 and the wedges 60 may then be driven out of the slots 58 and the links 35 pivoted away from cam bracket 38. The vessel bottom may then be removed although it will be appreciated that some force may be required to break the refractory which bonds the plug 18 to the refractory lining 15.

An alternate embodiment of the invention is shown in FIG. 5 wherein like portions of the apparatus are identified by the same reference numberal as in the embodiment of FIGS. l4. The embodiment of FIG. 5 differs from the previously discussed embodiment in that the swing bar is provided with threads 71 at its free end rather than a slot. A nut 74 is threadably received on threads 71 for forcing the clamp links 35 to pivot in the counterclockwise direction as shown in FIG. 5 to increase clamping pressure between roller 36 and cam plate 38. In order to provide a bearing face between nut 74 and

links

42 and 43 as clamp links 35 pivot, a washer 75 having a bearing face 76 which is in the form of a spherical section may be provided.

In the operation of the embodiment of FIG. 5 the furnace bottom replacement would be accomplished in a manner substantially identical to that discussed above with reference to the embodiment of FIGS. l-4 except that the nut 74 is loosened sufficiently to enable swing bar 70 and the swing clamp 35 to drop to vertical orientations and thereby allow the bottom to be separated from vessel 10.

The number and placement of clamping devices 13 around the vessel depends upon a number of factors such as size, shape, and weight of the vessel bottom. It should be obvious to one skilled in the art that the clamps should preferably be placed at equal intervals around the rim of bottom plate 19 so that the compres sive forces will be uniform and a tight seal can be accomplished. Maintaining uniform pressure around the periphery of bottom plate 19 may be extremely important as the vessel refining process proceeds and thermal stress developes in the bottom. It should also be evident that the clamping assemblies may be reversed, whereby clamp link 35 is mounted on the bottom plate 19 and swing bar 40 mounted on the vessel shell 11. While the invention has been described in connection with two preferred embodiments thereof. the invention may be variously embodied depending upon the particular converter, the size of the converter, the number and types of tuyeres etc. Accordingly, the invention then is not to be limited by the foregoing description but is to be limited solely by the claim which follow.

I claim:

1. In combination,

a refractory lined metallurgical refining vessel including an opening in the lower portion thereof for receiving a replaceable bottom assembly,

a replaceable bottom assembly for being inserted into said opening, tuyere means extending through said bottom for injecting process gases into molten metal to be contained in said vessel,

at least one clamping means including a first clamp means pivotally mounted on one of said vessel and bottom for movement into and out of a clamping position relative to the other of said bottom and vessel, a second clamp means mounted on the other of said vessel and bottom and engageable with said first clamp means when the latter is in its clamping position, said second clamp means including quick release locking means for securing said first clamp means in its clamped position to secure said bottom assembly to said vessel, and

engageable means mounted on the other of said vessel and bottom, said first clamp means being movable into engagement with said engageable means, said engageable means includes a surface having an end located a first radial distance from the pivot axis of said first clamp means and a second portion located a greater radial distance therefrom, said first clamp means including engagement means movable over said end and onto said surface as said first clamp means moves into its clamped position.

at least one clamping means including a first clamp means pivotally mounted on one of said vessel and bottom for movement into and out of a clamping position relative to the other of said bottom and vessel, a second clamp means mounted on the other of said vessel and bottom and engageable with said first clamp means when the latter is in its clamping position, said second clamp means including quick release locking means for securing said first clamp means in its clamped position to secure said bottom assembly to said vessel, engageable means mounted on the other of said vessel and bottom, said first clamp means being movable into engagement with said engageable means, said engageable means includes a cam surface generally normal to the pivotal axis of said first clamp rneans, s aid engageablemeans including a roller means rotatably mounted on said first clamp means about an axis generally parallel to that of said first clamp means.

3. The invention set forth in claim 1 wherein said second clamp means includes a longitudinal slot, said locking means including tapered wedge means receivable in said slot for engaging said first clamp means and for forcing said roller means into camming engagement with said cam surface.

4. The invention set forth in claim 1 wherein said clamp means has a threaded portion, said locking means including nut means receivable on saidthreaded portion for engaging said first clamp means and for forcing said roller means into camming engagement with said cam surface.

.5. The invention as claimed in claim 1 wherein:

one of said first and second clamp means includes parallel link means and the other of said clamp means comprising a single elongate member, said parallel link means straddling said single member when said first clamp means is in its clamping position.

6. The combination set forth in claim 1 wherein said bottom includes a refractory plug and a metallic bottom plate, a plurality of said clamping means disposed around the periphery of said opening with one of the clamp means of each clamping means being mounted on said vessel adjacent said opening and the other being mounted on said metallic bottom plate adjacent the periphery thereof.

7. In combination,

a replaceable bottom assembly for being inserted into said opening, tuyere means extending through said bottom for injecting process fluids into molten metal to be contained in said vessel,

at least one clamping means including a first clamp means pivotally mounted on one of said vessel and bottom,

cam means mounted on the other of said vessel and bottom, said first clamp means being pivotal in one direction for movement into clamping engagement with said cam means, further pivotal movement of said first means in said one direction acting to increase the clamping force between said vessel and bottom and pivotal movement in the opposite direction releasing said clamping force,

second clamp means releasably engageable with said first clamp means when the latter is in its clamping position, and means for securing said first clamp means in its clamping position.

8. The combination set forth in claim 7 wherein said bottom includes a refractory plug and a metallic support means, a plurality of said clamping means disposed around the periphery of said opening with one of the clamp means of each clamping means being mounted on said vessel adjacent said opening and the other being mounted on said metallic support means adjacent the periphery thereof.

9. The combination set forth in claim 8 wherein each of said first clamp means is generally elongate and has cam follower means mounted thereon and spaced from its pivotal axis for engaging said cam means.

10. The combination set forth in claim 9 wherein said cam means includes a cam surface extending in a direction generally normal to the pivotal axis of said first clamp means, said first clamp means including a pair of parallel link means and said second clamp means comprising a single elongate member, said parallel link means straddling said cam member and single member when said first clamp means is in its clamping position.

said cam surface.

Claims

1. In combination, a refractory lined metallurgical refining vessel including an opening in the lower portion thereof for receiving a replaceable bottom assembly, a replaceable bottom assembly for being inserted into said opening, tuyere means extending through said bottom for injecting process gases into molten metal to be contained in said vessel, at least one clamping means including a first clamp means pivotally mounted on one of said vessel and bottom for movement into and out of a clamping position relative to the other of said bottom and vessel, a second clamp means mounted on the other of said vessel and bottom and engageable with said first clamp means when the latter is in its clamping position, said second clamp means including quick release locking means for securing said first clamp means in its clamped position to secure said bottom assembly to said vessel, and engageable means mounted on the other of said vessel and bottom, said first clamp means being movable into engagement with said engageable means, said engageable means includes a surface having an end located a first radial distance from the pivot axis of said first clamp means and a second portion located a greater radial distance therefrom, said first clamp means including engagement means movable over said end and onto said surface as said first clamp means moves into its clamped position.

2. In combination, a refractory lined metallurgical refining vessel including an opening in the lower portion thereof for receiving a replaceable bottom assembly, a replaceable bottom assembly for being inserted into said opening, tuyere means extending through said bottOm for injecting process gases into molten metal to be contained in said vessel, at least one clamping means including a first clamp means pivotally mounted on one of said vessel and bottom for movement into and out of a clamping position relative to the other of said bottom and vessel, a second clamp means mounted on the other of said vessel and bottom and engageable with said first clamp means when the latter is in its clamping position, said second clamp means including quick release locking means for securing said first clamp means in its clamped position to secure said bottom assembly to said vessel, engageable means mounted on the other of said vessel and bottom, said first clamp means being movable into engagement with said engageable means, said engageable means includes a cam surface generally normal to the pivotal axis of said first clamp means, said engagement means including a roller means rotatably mounted on said first clamp means about an axis generally parallel to that of said first clamp means.

4. The invention set forth in claim 1 wherein said clamp means has a threaded portion, said locking means including nut means receivable on said threaded portion for engaging said first clamp means and for forcing said roller means into camming engagement with said cam surface.

5. The invention as claimed in claim 1 wherein: one of said first and second clamp means includes parallel link means and the other of said clamp means comprising a single elongate member, said parallel link means straddling said single member when said first clamp means is in its clamping position.

7. In combination, a refractory lined metallurgical refining vessel including an opening in the lower portion thereof for receiving a replaceable bottom assembly, a replaceable bottom assembly for being inserted into said opening, tuyere means extending through said bottom for injecting process fluids into molten metal to be contained in said vessel, at least one clamping means including a first clamp means pivotally mounted on one of said vessel and bottom, cam means mounted on the other of said vessel and bottom, said first clamp means being pivotal in one direction for movement into clamping engagement with said cam means, further pivotal movement of said first means in said one direction acting to increase the clamping force between said vessel and bottom and pivotal movement in the opposite direction releasing said clamping force, and second clamp means releasably engageable with said first clamp means when the latter is in its clamping position, means for securing said first clamp means in its clamping position.

11. The combination set forth in claim 10 wherein each of said second clamp means has a longitudinal slot formed therein, including tapered wedge means receivable in said slot for engaging said first clamp means and for forcing said cam follower means into camming engagement with said cam surface.

12. The combination set forth in claim 10 wherein each of said second clamp means has a threaded portion, nut means receivable on said threaded portion for engaging said first clamp means and for forcing said cam follower means into camming engagement with said cam surface.