US3679195A

US3679195A - Nose ring for metallurgical processing vessels

Info

Publication number: US3679195A
Application number: US65934A
Authority: US
Inventors: Stanley M Coulter; Ernst A Mevissen
Original assignee: Dravo Corp
Current assignee: Dravo Corp
Priority date: 1970-08-21
Filing date: 1970-08-21
Publication date: 1972-07-25
Anticipated expiration: 1989-07-25
Also published as: CA960457A

Abstract

A ring structure for cooling the nose or mouth portion of a metallurgical processing vessel, such as a basic oxygen furnace. The ring is formed of radially outwardly extending upper and lower plate members secured to the shell of the vessel at the mouth or nose portion thereof. An outer face plate is fixed at its axial ends to the upper and lower plates and is spaced from the vessel whereby a continuous coolant receiving cavity is defined. Coolant inlet and outlet openings communicating with the cavity are provided. Baffle plates are disposed throughout the coolant cavity for assuring turbulent flow of coolant through the ring to thereby improve heat transfer between the shell and the coolant. An outlet chamber is arranged in communication with the coolant outlet with a portion of the chamber being above the plane of the cavity for assuring complete filling of the cavity with coolant and thereby eliminating the possibility of formation of gas pockets in the ring.

Description

United States Patent Coulter et a].

[54] NOSE RING FOR METALLURGICAL PROCESSING VESSELS [72] inventors: Stanley M. Coulter, Wexford; Ernst A. Mevissen, Robinson Township, Allegheny County, both of Pa.

[73] Assignee: Dravo Corporation, Pittsburgh, Pa.

[22] Filed: Aug. 21, 1970 [21] Appl. No.: 65,934

[52] U.S. Cl...

Matsumoto et a1 ..266/36 P [451 July 25, 1972 Primary Examiner-Gerald A. Dost Attamey--Parmelee, Utzler & Welsh 57 ABSTRACT A ring structure for cooling the nose or mouth portion of a metallurgical processing vessel, such as a basic oxygen furnace. The ring is formed of radially outwardly extending upper and lower plate members secured to the shell of the vessel at the mouth or nose portion thereof. An outer face plate is fixed at its axial ends to the upper and lower plates and is spaced from the vessel whereby a continuous coolant receiving cavity is defined. Coolant inlet and outlet openings communicating with the cavity are provided. Baffle plates are disposed throughout the coolant cavity for assuring turbulent flow of coolant through the ring to thereby improve heat transfer between the shell and the coolant. An outlet chamber is arranged in communication with the coolant outlet with a portion of the chamber being above the plane of the cavity for assuring complete filling of the cavity with coolant and thereby eliminating the possibility of formation of gas pockets in the ring.

7 Claims, 7 Drawing Figures PAFENFEBJM 25 m2 SHEEF 1 BF 2 IN VENTORS STANLEY M. COULTER and ERNST A. MEV/SSEN lf/walla g/Qt Meir Arlorneys NLE Y M. COUL 75/? and .97 A. MEV/SSEN $431,424,- Mair Attorneys EP AITENFEDJMS m2 SHEET 2 BF 2 STA [RN NOSE RING FOR METALLURGICAL PROCESSING VESSELS This invention relates to apparatus for use in cooling the nose or mouth portion of metallurgical vessels, such as basic oxygen furnace, for example, and more particularly to a nose ring structure constructed to provide such cooling.

This invention will be described for use with a basic oxygen furnace, but it should be understood that it may be used with any metallurgical processing vessel.

Basic oxygen furnaces which are top blown have the familiar cylindrical or pear shape. The furnaces are usually supported for rotation by a trunnion ring having trunnions secured thereto. The furnaces can be thus tilted from the upright position to a completely inverted position for slag-ofi and to intermediate positions therebetween for metal tap-off through the nose or tapping mouth. The basic oxygen process generates tremendous amounts of heat subjecting the furnace to considerable thermal stress. The mouth or nose portion of the furnace is subjected to even greater stress than the rest of the furnace since it is exposed to the flame bursting out of the mouth from inside the furnace, radiation from the molten metal as its being poured into a ladle, and direct contact with spattering metal and slag. If preventive measures were not taken, the mouth portion of the furnace would tend to become distorted into an elliptical shape which would eventually cause loosening of the refractory around the mouth, thereby necessitating rebuilding of the mouth. One way of preventing distortion of the mouth portion is to fix a nose shield on the outside of the furnace surrounding the mouth of the furnace. The nose shield commonly used is merely a ring of solid metal and has not successfully eliminated the distortion of the mouth portion of the furnace. In addition, slag tends to build up on the solid nose shield. A liquid cooled nose ring has been designed for use with an open mouth furnace and is disclosed in US. Pat. No. 3,304,075. The nose ring of the patent will do a considerably better job of cooling the mouth portion of the furnace as compared with a solid shield. However, the nose ring of the patent is somewhat complicated in structure being spaced from the shell of the vessel, thereby necessitating appropriate support structure. The nose ring is spaced from the vessel in order to avoid thermal deformations between the hot shell of the vessel and the cooled parts of the ring. We consider that it is not necessary to space the cooled nose ring from the vessel if the nose ring is formed in accordance with our invention since the thermal deformation between the heated and cooled parts would be insignificant. We provide a nose ring for cooling the mouth portion of the vessel which is simple in construction and therefore relatively inexpensive to fabricate, while preventing distortion and refractory loosening. More particularly we provide apparatus for cooling the nose portion of a metallurgical processing vessel comprising preferably, ring means arranged on the outer shell of the vessel to surround at least part of the nose portion of the vessel and having top and bottom portions and an outer wall spaced outwardly from the vessel, the outer wall together with the op posing shell portion of the vessel and the top and bottom portions defining a coolant receiving cavity; and the ring means having a coolant inlet and outlet communicating with the cavity. Thus, we use the shell of the vessel as one wall of our cooling ring which we feel will provide a suflicient rate of heat transfer between the shell and the coolant to avoid any serious thermal stresses between the hot shell and the cool ring. Also, our ring results in a considerable cost saving in fabricating the ring as compared with a ring that is spaced from the shell of the vessel. As additional features to our invention, we provide baffle plates spaced throughout the coolant cavity in such manner to cause turbulent flow of coolant through the ring to thereby enhance the rate of heat transfer between the shell of the furnace and the coolant. Also, we assure that the entire cavity will be filled at all times with coolantby placing an out-' Other details and advantages of this invention will become apparent as the following description of a present preferred embodiment thereof proceeds.

In the accompanying drawings we have shown a present preferred embodiment of this invention in which:

FIG. 1 is an elevation view of a metal refining furnace which is top blown, and shown supported by a trunnion ring for tilting about a transverse axis, and also showing a nose ring constructed in accordance with the present invention for cooling the nose or mouth portion of the furnace;

FIG. 2 is a top plan view of the furnace of FIG. 1;

FIG. 3 is a section view looking along the line III-III of FIG. 1;

FIG. 4 is a section view looking along the line IV-IV of FIG. 1;

FIG. 5 is a section view looking along the line V-V of FIG. 1;

FIG. 6 is an enlarged fragmentary elevation view showing parts of the coolant inlet and outlet plumbing secured to the nose ring, and with parts cut away to show details of construction of the outlet chamber within the ring; and

FIG. 7 is a view looking along the line VII-VII of FIG. 6.

Referring now to the drawings, there is shown in FIGS. 1 and 2 an open mouth, generally cylindrical or pear shaped metal converting vessel or furnace 10 such as would be used in the basic oxygen refining of steel. Furnace 10 is illustrated as being supported for tilting about a transverse axis thereof by a hollow water cooled trunnion ring 12 to which is fixed diametrically opposed trunnions 14. Both trunnions are arranged in ground supported bearings, one trunnion being driven and the other, in this case trunnion 14, serving as an idler trunnion.

Furnace 10 has a steel outer shell 16 and a refractory lining 18. A nose ring, generally designated 20, is secured to the outer shell 16 adjacent the mouth 22 of the furnace. The nose ring 20 extends completely around the mouth portion of the furnace, and includes an annular top plate 24 secured to the shell 16 as by welding for example, and extending radially outwardly from the furnace, lying generally in a horizontal plane when the furnace is in the upright position. An annular bottom plate 26, axially spaced and generally parallel to top plate 24, is secured to shell 16 as by welding, for example. A generally cylindrically shaped outer face plate 28 is radially spaced from shell 16 and is fixed at its upper and lower ends to the top and bottom plates, respectively. Thus, outer face plate 28 and the opposing portion of shell 16 together with top and

bottom plates

24 and 26 define an annular cavity 30 around the nose or mouth portion of furnace 10. An annular lip ring 32, formed of arcuate segments, is removably secured to the top surface of top plate 24, as by nuts and bolts. The lip ring 32 surrounds mouth 22 of furnace 10.

The nose ring 20 is provided with a coolant inlet 36 in the form of an opening through a lower section of face plate 28 and a coolant outlet 38 in the form of an opening through an upper section of face plate 28 the centerline of which opening lies in a vertical plane closely spaced to the vertical plane including the center line of the opening of inlet 36. An axially extending partition plate 40 is disposed about midway between inlet 36 and outlet 38 and extends from an inner surface portion of outer face plate 28 to an opposing portion of shell 16. Partition plate 40 thus interrupts cavity 30 to create a counterclockwise flow path, as viewed in FIG. 2, between inlet 36 and outlet 38. As shown in FIG. 1, plumbing and suitable valving are arranged with inlet 36 and outlet 38 for directing a coolant, such as water for example, into and out of ring 20. The coolant will flow in and out of concentric plumbing arranged through trunnion 14. As illustrated, inlet coolant will flow directly into nose ring 20 through inlet 36 and will discharge through outlet 38 into the hollow trunnion ring 12 and then out through the trunnion 14.

A series of arcuately spaced baffle plates are arranged in cavity 30 for disrupting the flow of coolant through ring 20 which will result in a more or less turbulent flow of coolant, thereby enhancing the heat transfer characteristics of the coolant. Four such bafile plates are illustrated, two of which plates 42 abut bottom plate 26 and are secured to the shell 16 and extend radially outwardly to adjacent the face plate 28 and axially upwardly to an intermediate point of cavity 30. Two plates 44 abut top plate 24 and are secured to shell 16 and extend radially outwardly to adjacent face plate 28 and axially downwardly to a point below the upper end of plates 42. The

plates

42 and 44 are staggered so that an upwardly extending plate 42 follows a downwardly extending plate 44. Both

plates

42 and 44 are spaced from face plate 28 to allow coolant to flow between the radial edges of the plates and the face plate 28.

An outlet chamber 50 is disposed in cavity 30 in communication with outlet 38. Outlet chamber 50 includes a plate member 52 having a centrally disposed pocket 54 with an open top formed in one face thereof. Plate member 52 is secured to an inner surface portion of face plate 28 such that the pocket 54 completely surrounds outlet 38. The plate member 52 is of such thickness that the rear face thereof is spaced from the shell 16 to permit coolant to flow between the rear face and the shell. A slot 60 is provided in upper plate 24 above plate member 52 and communicates with the pocket 54. Slot 60 extends beyond both sides of plate member 52 as shown in FIG. 6. Thus, coolant flowing from inlet 36 to outlet 38 would have to enter outlet chamber 50 before entering outlet 38. The flow of coolant will be into the ends of slot 60 and in the space between the back of plate member 52 and shell 16 in to slot 60 through the back portion thereof. By having to flow to a point above the top of cavity 30 (i.e. into slot 60) the coolant will always fill the cavity 30 and thereby eliminate formation of air pockets along the upper portion of cavity 30. Air pockets in cavity 30 would decrease the rate of heat transfer between the shell comprising the mouth portion of the furnace and the coolant in ring 20.

By using the shell of furnace as one wall of our nose ring, we are able to cool the mouth portion of the furnace without any damaging thermal stresses being built up between the shell and the other plates forming the nose ring. Thus, our nose ring effectively cools the mouth portion of the furnace and in addition is simple in structure and relatively inexpensive to fabricate as compared to a nose ring supported in spaced relation to the mouth of the furnace. Also, our nose ring will add support to the mouth portion of the furnace which is normally the weakest part of the furnace. Cooling the nose ring will increase the support given to the mouth portion by the nose ring.

While we have shown and described a present preferred embodiment of this invention, it is to be distinctly understood that the invention is not limited thereto but may be otherwise variously embodied within the scope of the following claims.

We claim:

1. Apparatus for cooling the nose portion of a metallurgical processing vessel, comprising:

ring means arranged on the outer shell of the vessel to surround at least part of the nose portion of the vessel and having top and bottom portions and an outer wall spaced outwardly from the vessel, said outer wall together with the opposing shell portion of the vessel and said top and bottom portions defining a coolant receiving cavity; said ring means having a coolant inlet and outlet communicating with the cavity; a plate member having one face thereof fixed to the inside of said outer wall with the other face spaced from the shell of the vessel and having a pocket therein communicating with said outlet; and said top portion of the ring means having a slot therein communicating with said pocket and extending circumferentially beyond the sides of said plate member.

2. The apparatus as set forth in claim 1 including a plurality of baffle plates arcuately spaced in the cavity and extending to an intermediate position in the cavity.

3. Apparatus for cooling the nose portion of a top blown metallurgical vessel comprising:

ring means arranged on the outer shell of the vessel to surround at least part of the nose portion of the vessel and having axially spaced, radially outwardly extending top and bottom plates secured to the outer shell and an outer face plate fixed at the axial ends thereof to the top and bottom plates and radially spaced from the outer shell of the vessel, the outer face plate together with the opposing shell portion of the vessel and the top and bottom plates defining a coolant receiving cavity;

said ring means having a coolant inlet and outlet commu nicating with the cavity; and

means defining an outlet chamber in the cavity communicating with the coolant outlet and having an upper portion spaced above said cavity whereby coolant must flow into the upper portion before being discharged from said outlet.

4. The apparatus as set forth in claim 3 including arcuately spaced baffle plate members disposed in said cavity for directing the flow of coolant in a staggered path to provide a turbulent flow of the coolant within the ring means.

5. The apparatus as set forth in claim 3 wherein said coolant inlet is disposed below said coolant outlet with the vessel in the upright position, and said coolant inlet further having the vertical centerline thereof in a vertical plane adjacent to the vertical plane including the vertical centerline of said coolant outlet.

6. The apparatus as set forth in claim 3 including a partition member in said coolant receiving cavity intermediate said coolant inlet and said coolant outlet for interrupting the cavity and such that coolant will flow through said cavity from said coolant inlet to said coolant outlet.

7. The apparatus as set forth in claim 3 including first plumbing means coupled to said coolant inlet for directing coolant into said ring means, and second plumbing means coupled to said coolant outlet for receiving coolant from said ring means and directing same into a hollow trunnion ring surrounding the vessel.

Claims

1. Apparatus for cooling the nose portion of a metallurgical processing vessel, comprising: ring means arranged on the outer shell of the vessel to surround at least part of the nose portion of the vessel and having top and bottom portions and an outer wall spaced outwardly from the vessel, said outer wall together with the opposing shell portion of the vessel and said top and bottom portions defining a coolant receiving cavity; said ring means having a coolant inlet and outlet communicating with the cavity; a plate member having one face thereof fixed to the inside of said outer wall with the other face spaced from the shell of the vessel and having a pocket therein communicating with said outlet; and said top portion of the ring means having a slot therein communicating with said pocket and extending circumferentially beyond the sides of said plate member.

3. Apparatus for cooling the nose portion of a top blown metallurgical vessel comprising: ring means arranged on the outer shell of the vessel to surround at least part of the nose portion of the vessel and having axially spaced, radially outwardly extending top and bottom plates secured to the outer shell and an outer face plate fixed at the axial ends thereof to the top and bottom plates and radially spaced from the outer shell of the vessel, the outer face plate together with the opposing shell portion of the vessel and the top and bottom plates defining a coolant receiving cavity; said ring means having a coolant inlet and outlet communicating with the cavity; and means defining an outlet chamber in the cavity communicating with the coolant outlet and having an upper portion spaced above said cavity whereby coolant must flow into the upper portion before being discharged from said outlet.