US1769495A - Furnace - Google Patents

Description

Patented July 1, 193()` UNITED STATES GEORGE I. DANFORTH, JR., OF CHICAGO,

r-ATENT OFFICE:

ILLINOIS, ASSIGNOR, BY IIESNE ASSIGN- MENTS, TO OPE!l HEARTH COMBUSTION COMPANY, OF CHICAGO, ILLINOIS, A

' conronArIoN or DELAWARE FTTRNACE Original application led September 26, 1921, Serial No. 503,241. Divided and this application fled .April 4, 1930. Serial No. 441,543.

This invention relates to a new and improved openhearth furnace, and more particularly to a construction adapted to so direct the entering Y'gases and air in an open l hearth furnace as to produce a quick burning and intensely hot flame adapted to provide working heat adjacent the fullsurface of the metal in .the furnace, and further adapted to provide a large port area through which to I0 exhaust the products of combustion.-

This application is a division of my copending application Serial No. 503,241 filed September 26, 1921.

My invention comprises an improvement in that portion of an open hearth furnace between the ports and the bath or melting chamber, and the remainder of the furnace and its appurtenances may be of any usual construction. As is well known in open hearth practice, the furnace is double-ended and reversible, and is provided -at each end with gas or air ports which serve upon the outgoing end to carry off the products of combustion. In certain types of these fui` naces burning producer orlike gases, these incoming gases are passed through regenerative chambers and are thus preheated. The incoming air is preheated in a similar manner and the heat of the furnace flame is correspondingly increased. It is highly desirable in such furnaces to provide a short,

quick ame which is directed toward the metal in the bath and which does not extend to the outgoing end of the furnace. Howserve both to introduce'thel air and as and to carry off the products of combustlon, the latter function has been -largely the determining factor as regards the size of ports. This isgor the reason that the products of combustion are of considerably greater volume than the incoming air and gas.

To secure a short, uick Haine, it is essentialthat there be a quick and thorough mixture of the incoming air and gas. It is impractical to secure such a mixture and flame when the air and gas ports are of the usual comparatively large area.' Endeavors are made to secure this quick mixture with such 5 ports by surrounding the gas stream upon its ever, in actual practice, since the same ports due modification of the sides and top with the air stream. However,- the intermixture in general occurs gradually as the gas is passed across the furnace, the lighter gas gradually rising and intermingling with the heavy air, combustion thus gradually taking place.

Endeavors have been made to secure a quick mixturev and short flame by means of uslng comparatively small air and gas ports and providing auxiliar ports for carrying olf the products of com ustion, for example, as shown in the patent to Frank B. McKune, No. 1,339,855, issued May 11, 1920. In such constructionsdampers are providedto close the auxiliary passages upon the incoming end of the furnace. The addition of auxiliary ports' and uptakes unduly complicates the structure and this is particularly true in the usual type of furnace burning producer or similar gases. In such furnaces, as generally constructed, a single gas uptake and port is flanked by an air uptake and port upon each side thereof. All these ports are essential to the operation of a furnace upon the incom-v ing end, although ashas been stated, the port area is increased over that necessary for the incoming air and gas in order to be of a size adequate to take care of the products of combustion.

It is an object of the present invention to provide means located intermediate the ports and the furnace chamber which meansv are adapted to vary the effective passage area between the ports and chamber. l

It is a further ob'ect to rovidemeans of 85 this character whic are a justable to provide the full port area for handling the products of combustion.

It isian additional object to provide means whichmay be readily installed without un-- existing furnace structure. Y Y

' It is also an object to provide a device which is relatively simple in design, construction and'operation.

Other and further objects will appear as Y the description proceeds. Broadly my invention comprises the interposition of dampers between the ports and furnace chamber, these dampers being ad'- IUI justable to vary the effective passage area. I

v have illustrated a preferred embodiment of my invention in the accompanying drawing, in which- Figure 1 is a fragmentary, longitudinal section of an open hearth furnace having my invention applied thereto; and

Figure 2 is a horizontal section of the form of construction shown iii Figure 1.

The form of construction shown in the drawing comprises the gas uptake 81 terminating in the gas port 82. The air uptakes 83 are located upon either side of the lgas uptake and meet at 84 above that uptake. Otfsets are formed in the lateral walls of the furnace adjacent the air uptakes and watercooled hinge plates 85 are located in these offsets. The Water-cooled dampers 86 are swung upon these hinges and are adapted to be swung to a position such as that shown in Figure 2 to direct the incoming air inwardly against the incoming gas. Upon the outgoing end of the furnace, the dampers are swung outwardly parallel with the furnace wall and they thus permit the full area of the ports to be effective in carrying ofi' the product-s of combustion.

The form of construction which I have shown serves to restrict the effective passage area between the ports and the furnace upon the incoming end of the furnace. It thus causes a quick mingling of air` and gas and a` short flame upon the incoming end and fur-y ther permits the ready discharge of' tlieproducts of combustion through the full port area. Modifications of my construction may be made and it is my intention to cover all variations coming within the spirit and scope ofthe appended claims.

I claim:

1. In an open hearth furnace, the comthe cross sectional areas of the passages and means for introducing gas into the, passages at points anterior tothe gates or valves.

2. An end .construction for regenerative open hearth furnaces having a throat for the passage of fuel to the hearth or for the escape of products of combustion, and means for varying the effective area of the throat including a damper movable into the throat from the side. y

ZipAnV end construction for regenerative open hearth furnaces having a throat for the passage of fuel to the hearth o r for the escape of 4products of combustion, and means for varying the leffective area of the throat April, 1930.

open hearth furnaces having a throat at the end of the hearth, means for delivering gas centrally to the throat, means for delivering air to the throat to each side of the gas supplied, and daiiipers horizontally movable into and out of the throat for varying its effective area, the damper converging toward the hearth to direct the incoming air toward `the stream of incoming gas.

6. In a regenerative reversing furnace, a-

combustion aiid an exhaust port, a damper pivotal] y mounted at one end in the port, and means for nioving"tlie damper to vary the area of the port.

Signed at Chicago, Illinois, this 1st day of GEORGE L. DANFORTH, JR..

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