US2321074A - Water cooled skewback casting - Google Patents

Description

June'8, 1943. c. R. FoN DERsMlTH -r-:TAL 2,321,074

WATER COOLED SKEW BACK CASTING Filed Jan. 2'?, 1941 dc RF IAb/ENIOR;

3,0' I2 Byg Mulan/K Eska/MNM ATTORNEYS.

Patented June 8, -1943 UNlTED STATES PATENT iOFFlCE WATER COGLED SKEWBAGK CASTING Charlesilt.` Fony IDersmith and -William 'Wn Bergmann, 'Middletowm Ohio, assignors .to The American-Rolling Mill Company, Middletown, '.0hio, a corporation of Ohio Application January 27, 1941, SerialNo. 376,662

Claims.

Our invention-relates to the provision of furnace elements in open hearth practice ofthe type known as skew backs, which-are generally prism-shaped supporting means used at the juncture of two walls which do not meet-each other at VrightA angles. Skew backs are used, for example,

v angular cross section with odd shaped refractory bricks. This procedure involves a number ofdisadvantages. The odd shaped refractory bricks are themselves expensive, andbecause vof their shape, somewhat fragile. AIt is laborious,Y and expensive to build up the skew back as such. When built, 4the skew back 4mayhave an insufficient strength'factor. The refractory 'parts are subject to the destructive influences ofhigh heats and relatively high furnace gas velocities, and it is necessary to replace the skew back structure substantially every time the furnace is taken down or repaired.

It is a fundamental object of our' invention to provide a skew back of substantially permanent character,` better able to withstand the strains of use; made of metal,'but protected'from' the high furnace heats by cooling (adequately localized and distributed), and of relatively inexpensive construction. YIt is a fundamental object of our invention also to'provide a solution for those vproblemsheretofore inherent in skew back constructions.

These'and other objects of'our invention which ywill l-be setV forth hereinafter or willbe apparent to one skilled in the art upon reading these speci- -fications, welaccomplish `|by that certainl constructionv and'arrangement of `parts of which we shall now describe an-exemplary embodiment. Reference ismade to the drawing, wherein:

Figure 1 is VYa sectional -view lacross a typical open-hearth furnace construction. Fig. 2 is an' elevational view-cfa typical skew back construction madeinfaccordance with our invention.

Fig. 3 is a sectional View thereof taken along the lines 3-3 of Fig. 2.

Figmifis Aa sectional-view of a skew-backconstruction showingv a modie'dformof water-cooling arrangement.

.We .havegfound'thative canmakea metalskewts back structure, eliminating all necessityfor the use of skew brick, providing the structure is first properly shaped for the service it is to perform, second, made adequately strong and resistant to the stresses encountered in service, and third, kept-cool in 'such a way as to counteract the destructive effect of high temperature and high gas velocity at those points at which the structure is most subject to them.

In'Fig. l we have illustrated a hearth portion of an open-hearth furnace in crosssection. The hearth proper is illustrated at l, and is provided with the usual chemically active hearth lining 2. Metal support or frame members, usually in the form of I-beams, are illustrated at 4 and 5. The top or roof of the furnace E, is in the form of an arch supported at its opposite ends on the skew backs which we will now describe.

Our skew backs are referred to herein as castings, and are most conveniently made in that form; but it will be understood that a metallic device of similar physical characteristics may be otherwise fabricated if desired .as by being made of heavy metal plates welded together. Our casting-,has a front or skew face 1, which in the furnace will be disposed at an angle to the vertical supports 4 and 5 so as to bear the end thrust loads of the arch 6. Above, the skew face preferably terminates in a vertically disposed portion 8 which may be perforated as at 9 for the reception .of bolts I0 or other fastening members whereby it may be affixed to the verticalk supports. It will be understood that the vertical supports 41and5 are frequently tied across above the roof of the furnace, by rods or otherwise, to withstand the end thrusts of the room. The vertical portion 8 may have at its top a horizontal stiffening rib ll.

At the bottom of the skew face we provide a horizontal rib l2`of such width as to bring its rear edge into substantial alignment with the portion 8. At the ends of the skew back, and on the rib I2 wemay provide ears I3 perforated as at I4 for additional fastening'means whereby to anchor the skew back to the supports. Intermediate the skew face l we prefer to provide another stiifening rib I5, again of such length as to bring its free edge into substantial alignment with the portion 8. l

The skew back castings `as shown may be made in units of such length as to extend between and preferred by ,us since iin-,eliminates:thehandling of excessively large castings and also permits the renewal of sections which become damaged.

The structure thus far described is a skew back having the proper conformation and the proper strength for handling the physical stresses to be imposed upon it but provision must be made for cooling it to enable it to withstand the excessive heats of the furnace. The necessity for cooling is greatest at the nose'of the skew back, i. e. at the juncture of the skew face 'I and the lowermost reiforcing rib I 2. It is necessary at this of this chamber will be closed as described above, and the plate 32 will be provided with conduit means 34. Additional cooling above the rib I may be provided where desired, by employing a plate 35 to form a cooling chamber 36, closed at its ends, and provided with conduits 3l after the manner which has been described in connection with cooling chambers 28 and 33.

line of juncture to have very efcient cooling and a uniform, controlled and confined application of the cooling fluid. It is well also, however, to have supplementary cooling elsewhere in that portion of the back covered by the refractory of the roof. As a consequence of this we prefer to provide at least one other cooling chamber in or in connection with the backs. Where the backs are castings, we prefer to form these chambers by the use of cores in the mold, giving'us chambers for cooling fluid which are closed except at the inlet and outlet portion. Our chambers are preferably formed in the casting itself by supplementary walls I6 and Il acting in conjunction both with the skew face I and with the ribs I2 and I5 respectively. We have shown the wall I6 as lying aslant both to the skew face l and the rib I2, and with these parts forming the cross sectional boundary of a cooling chamber I8. The

coring is done in the molds in such a way that the chamber I8 is closed at its ends as shown at I9 and 20. An upper cooling chamber 2| is formed in a similar manner, though here for ex ample, for the sake of sufficient internal volume, the wall I'I may be disposed substantially parallel to the portion 8. Again the coring in the molds is done in such a way that the chamber' 2I is closed at its ends as at 22 and 23. At either end of the chambers I3 and 2I we provide openings to which inlet or outlet tubes 24, 25, 26 may be threaded, welded, or otherwise attached. These will be connected by suitable conduits respectively to a source of cooling fluid and to a drain or reservoir for the overflow. The chamber I8 is so located that it efficiently cools the actual nose of the skew back while the chamber 2I located up the skew back face furnishes additional cooling.

The localization of cooling at the nose is vital in a construction of this character, we have found. In some cases no supplemental cooling will be necessary. In other cases additional supl plementary cooling maybe found advisable, and it may be found advisable to vary the position of such supplementary cooling. In Fig. 4 we have shown a skew back in which like parts have been given like index numerals, but in which the cooling chambers are not cast orotherwise formed integral with the back. In therconstruction of Fig. 4, we have shown a nose cooling chamber 2S formed by bridging across the faces I2 and 'I with a plate 29. This plate will be welded to the faces as at 30 to form the chamber, and the ends of the chamber will be closed by shaped metal portions welded both to the plate 29 and to the faces 'I and I2, about the periphery of the end piece. The plate 29 will be provided with inlet and outlet openings to which tubular members 3| may be attached. Where supplementary cooling is needed, adjacent the nose-coolingchamber 28, we make use of an angularly bent plate 32, the lower leg of which is welded to the skew face 1 and the upper leg of which is welded to theintermediate rib I 5. This provides a` cooling charnber 33 also located beneath the rib I5. The ends Additional attachment ears 38 may be provided on the upper rib. We prefer to make our skew backs of cast steel or cast iron; but the invention is not limited to this material, excepting where specifically claimed.

Modifications may be made in our invention Without departing from the spirit of it.

Having thus described our invention, what we claim as new and desire to secure by Letters Patent, is:

1. In a skew back construction an angularly disposed wall lproviding a skew face, a vertical wall joining the skew face at the top whereby the skew back may be attached to supports, a horizontal stiffening rib at the 4bottom of the skew face and of a width to give the skew back a substantially triangular formation, a slanting wall extending between the front wall and the stiiening rib and spaced both from the edges of said walls and from the juncture thereof to provide a chamber for cooling fluid located at and substantially confined to the nose of said skew back, and connections to said chamber for ingress and egress of cooling fiuid.

2. In a skew back construction an angularly disposed wall providing a skew face, a vertical wall joining the skew face at the top whereby the skew back may be attached to supports, a horizontal stiffening rib at` the bottom of the skew face and of a width to give the skew back a substantially triangular formation, a slanting wall extending between the front wall and the stiffening rib and spaced both from the edges of said walls and from the juncture thereof to provide a chamber for cooling fluid located at and substantially confined to the nose of said skew back, and connections to said chamber for ingress and egress of cooling fluid, said front wall having intermediate its edges a second substantially horizontal stiffening ri 3. In a skew back construction an angularly disposed wall providing a skew face, a vertical wall joining the skew face at the top whereby the skew back may be attached to supports, a horizontal stiifening rib at the bottom of the skew face and ofa width to give the skew back a substantiallyV triangular formation, a wall extending between the front wall and the' stifening rib and interspaced from the juncture thereof to provide a chamber for cooling :duid located at the nose of said skew back, and connections to said cham-ber for ingress and egress of cooling fluid, said front Wall having intermediate its edges a second substantially horizontal stiffening rib, and a wall joining said second rib and said front wall and interspaced from the juncture thereof so as toprovide a second cooling chamber, means closing the ends of said cooling chamber, and connections thereto for ingress and egress of said cooling fluid. Y

4. The structure claimed in claim 1 nwhich all of said wall portions are parts of an integral cast structure including the portions closing the ends of said cooling chamber, said cooling chamber having the characteristics of havingbeen formed in a cored mold.

5. In a skew back construction an .angularly disposed wall providing a skew face, a vertical wall joining the skew face at the top whereby the skew back may be attached to supports, a horizontal stiiening rib at the bottom of the skew face and of a width to give the skew back a substantially triangular formation, a wall extending between the front wall and the stiiening rib and interspaced from the juncture thereof to provide a chamber for cooling fluid located at the nose of said skew back, and connections to said chamber for ingress and egress of cooling iiuid, said front wall having intermediate its edges a second substantially horizontal stiffening rib, and a wall joining said second rib and said front wall and interspaced from the juncture thereof so as to provide a second cooling chamber, means closing the ends of said cooling chamber, and connections thereto for ingress and egress of said cooling fluid and in which the said wall portions including the ends of the said cooling chambers are all integral parts of a single metallic casting.

6. A cast iron or steel skew back comprising a front wall providing a skew face terminating upwardly in a substantially vertical wall, providing an attachment portion, the said front wall lbeing provided along its bottom edge and intermediate its length with stiffening ribs of such width respectively as to give to the entire skew back a substantially triangular cross section, and means for confining a cooling fluid within said back to an area adjacent the line of juncture between said front wall and the lowermost one of said ribs.

7. A cast iron or steel skew back comprising a front wall providing a skew face terminating upwardly in a substantially vertical wall, providing an attachment portion, the said front wall being provided along its bottom edge and intermediate its length with stiffening ribs of such width respectively as to give to the entire skew back a substantially triangular cross section, one of said ribs at least being provided at its ends with substantially vertical ears whereby said back may be further attached to a support, said vertical portion attached to said front wall terminating upwardly in a substantially horizontal, forwardly extending stiiening rib, and means for conning a cooling fluid within said back to an area adjacent the line of juncture of said skew face and the lowermost of said ribs.

8. A cast iron or steel skew back comprising a front wall providing a skew face terminating upwardly in a substantially vertical wall providing an attachment portion, the said front wall being provided along its bottom ledge and intermediate its length with stiilening ribs of such width respectively as to give to the entire skew back a substantially triangular cross section, and means for conning a cooling fluid within said back to an area adjacent the line of juncture between said front wall and the lowermost one of said ribs, said means comprising an angularly disposed plate having its edges welded both to the front wall and to the said rib so as to provide a cooling chamber, and means at the end of said plate for closing off the ends of said cooling chamber.

9. A cast iron or steel skew back comprising a front wall providing a skew face terminating upwardly in a substantially vertical wall providing an attachment portion, the said front wall being provided along its bottom edge and intermediate its length with stiffening ribs of such width respectively as to give to the entire skew back a substantially triangular cross section, and means for conning a cooling fluid within said back to an area adjacent the line of juncture between said front wall and the lowermost one of said ribs, said means comprisng an angularly disposed plate having its edges welded both to the front wall and to the said rib so as to provide a cooling chamber, means at the end j of said plate for closing off the ends of said cooling chamber, and additional cooling means comprising an angularly bent plate extending longitudinally of said back and having its edges welded respectively to said front wall and to the uppermost one of said ribs so as to provide a cooling chamber lying beneath said rib, and means for closing the ends of said cooling chamber.

10. A cast iron -or steel skew back comprising a front wall providing a skew face terminating upwardly in a substantially vertical wall providing an attachment portion, the said front wall being provided along its bottom edge and intermediate its length with stiffening ribs of such width respectively as to give to the entire skew back a substantially triangular cross section, and means for confining a cooling iluid within said back to an area adjacent the line of juncture between said front wall and the lowermost one of said ribs, said means comprising an angularly disposed plate having its edges welded both to the front wall and to the said rib so as to provide a cooling chamber, means at the end of said plate for closing oil the ends of said cooling chamber, and additional cooling means comprising an angularly bent plate extending longitudinally of said back and having its edges welded respectively to said front wall and to the uppermost one of said ribs so as to provide a cooling chamber lying beneath said rib, means for closing the ends of said cooling chamber, and means located above said uppermost rib for forming still another cooling chamber, said means comprising a metal plate welded along its edges respectively to said front wall and to said uppermost rib, and means for closing off the ends of said cooling chamber, said cooling chambers being provided with inlet and outlet means.

CHARLES R. FON DERSMITH. WILLIAM W. BERGMANN.

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