US2599832A

US2599832A - Stopper head for ladles

Info

Publication number: US2599832A
Application number: US117131A
Authority: US
Inventors: Abram L Hodge
Original assignee: United States Steel Corp
Current assignee: United States Steel Corp
Priority date: 1949-09-22
Filing date: 1949-09-22
Publication date: 1952-06-10
Anticipated expiration: 1969-06-10

Description

June 10, 1952 A, HODGE 2,599,832

STOPPER HEAD FOR LADLES Filed Sept. 22. 1949 Whg - I4/venian @BBQ/V #05655,

i5 gib/6g Patented June 10, 1952 2,599,832 A STOPPER HEAD FOR LADJES Abram L. Hodge, Buffalo, N. Y., assignor to United States Steel Company, a corporation of New Jersey Application September 22, 1949, Serial No. 117,131

2 Claims. (Cl. 22e-85) This invention relates to improvements in stopper heads for ladles of the bottom pour type used'for transferring molten metals.

These ladles have linings of refractory brick- Work `which withstand the temperature of the molten metal, which in the case of iron and steel is 2350D F. and higher. The ladles have a pouring nozzle through their bottom walls. A stopper, which extends from the top of the ladle and is operated by external mechanism, controls ow of molten metal through said nozzle. The parts of the nozzle and stopper head which are exposed to the molten metal commonly are of graphite composition, Which furnishes better resistance to erosion than the brickwork, although it is less refractory. A low carbon steel head pin fixes the graphite parts to the stopper rod and this head pin is the part which often fails. In ladles which are used for teeming molten steel into ingot molds the life of a stopper head is brief, being approximately suilicient only to teem one ladle. Serious damage can result when a stopper head fails before the .ladle is empty.

An object of the present invention is to provide improved stopper heads which have a longer life than usual stopper heads With which I am familiar, and therefore are less likely to fail prematurely. f

A further object of the invention is to provide improved stopper heads in which the head pin is insulated from the parts which contain graphite, an arrangement which reduces both conduction of heat to the pin and carburization of the pin.

In accomplishing these and other objects of the invention, I have provided improved details of structure, a preferred form of which is shown in the accompanying drawing, in which:

Figure l is a vertical sectional view of a portion of a ladle showing a typical arrangement of pouring nozzle, stopper and operating mechanism: and

Figure 2 is a vertical sectional view on an enlarged scale of a stopper head which embodies features of the present invention.

Figure 1 shows a portion of a typical ladle which comprises an outer shell I and a lining I2 of refractory brickwork. The ladle has a pouring nozzle I3 and a stopper for said nozzle which includes a head I4, a rod I5, refractory sleeves I6 and operating mechanism I1. In accordance with usual practice, the exposed parts of the nozzle and stopper head are of a graphite composition.

. Inasmuch as the foregoing parts, aside from the stopper head, can be of any standard construction, lno more detailed description is deemed necessary.

Figure 2 shows the details of stopper head I4. The head comprises a low carbon steel head pin I8, a key I9 which removably fixes said pin to the lower end of rod I5, and a graphite composition plug 20 carried by said pin. The lower end of head pin I8 has a ilange 2| which is received in a counter-bore 22 in the lower end of plug 20. Bore 22 is of appreciably greater depth than the thickness of ilange 2l. and contains a filling 23 of graphite composition. A layer 24 of similar composition separates plug 20 and the lowermosty v sleeve I6.

A stopper head constructed as just described commonly fails through melting of the flange on the head pin. This pin is of a low carbon steel in order that it has the highest melting temperature possible. Nevertheless, in usual constructions contact between the graphite plug and the flange of the head pin both conducts heat to this flange and carburizes it so that its melting temperature is lowered. Graphite has relatively high heat conductivity compared with other refractories.

In accordance with the present invention, a refractory disc 25 separates filling 23 from the bottom face of flange 2I of the head pin. Likewise a washer 26 separates plug 20 from the top face of said ange. The washer and disc commonly are 1A; to 1A inch thick and their outside diameters are slightly larger than the diameter of the flange. An air gap 21 separates plug 20 from the circumference of said flange.

Disc 25 and washer 26 are of a material that is substantially carbon-free and capable of withstanding temperatures up to about 2600 F. I have found that unburned diatomaceous earth is especially good, but that these parts conveniently can be cut from bricks of burned diatomaceous earth. Such bricks are available commercially as Johns- Manville C-22 Silocel Brick. Other Suitable materials are alumina, sillimante and mullite.

From the foregoing description it is seen that the present invention provides means for maintaining the flange of the head pin out of contact with partswhich contain graphite. Therefore the present invention prolongs the life of modifications may arise. Therefore, I do not wish to be limited to the disclosure set forth but only by the scope of the appended claims.

I claim:

1. In a stopper head for ladles which includes a head pin of low carbon steel adapted to be fixed to a stopper rod and having a ange at its lower end, a plug of graphite composition carried by said head pin and having a counter-bore at its lower end 'of appreciably greater depth than the thickness of said flange receiving said flange, and a filling of graphite composition said counter-bore, means insulating said flange from the adjacent parts that contain graphite and thereby minimizing heat conduction to said ange and carburization of said ange comprising a disc of substantially carbon-free refractory insulating material separating the lower face of said ange from said filling and a washer of substantially carbon-free refractory insulating material separating'the upper face of said flange from said plug, there being an Aair gap between the circumference of said ange and said plug, said insulating material being capable of withstand-y ing temperatures up to about 2600" F. y Y

2. In a'stopper head for ladles which includes a head pin of low carbon steel adapted to be xed to a stopper rod and having a flange at its lower end, a plug of graphite composition carried by said head pin and having aV counter-bore at its lower end of appreciably greater depth than the thickness of said flange receiving said flange,

and a'. iilling o'f graphite composition in said counter-bore, means insulating said ange from the adjacent parts that contain graphite and thereby minimizing heat conduction to said flange and carburization of said ange comprising a disc of diatomaceous earth separating the lower face of said flange from said illling'and a washer of diatomaceous earth separating the upper face of said flange from said plug, said disc and said Washer having a thickness approximately between 1/8 and 1A; inches and an outside diameter slightly greater than said flange, there being an air gap between the circumference of said flange and said plug.

ABRAM L. HODGE.

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

UNITED STATES PATENTS tion, by Gregory. Published 1942 by Reinhold Publishing Corp., New York, N. Y., pages 232, 233.