US1787464A - Furnace-wall construction - Google Patents

Description

Jem 6, 1931. J. E. ANDERsoN 15737334 rummcs WALL consl'xaucl'ron mea nov. 1s, 1926 25mn-sheet 14 @gaf Patented Jan. 6, 1931 UNITEDA STATES PATENT OFFICE JOHN E. ANDERSON, OF CHICAGO, ILLINOIS, ASSIGNOR TO PLIBRICO JOINTLESS FIRE- BRICK COMPANY, OIE` CHICAGO, ILLINOIS, A. GOREORATION F ILLINOIS rUnNAcn-wenr. cons'rnncron Application led November'l, 1926. Serial No. 149,072.

This invention relates to furnace construction, and more particularly to a hollow wall construction for furnaces. Y

.It has been recognized that greater efficiency in operation could be obtained by providing air spaces in the wall construction serving to insulate, to a certain extent, `the refractory lining of the furnace chamber from the outer retaining wall so as to prevent deterioration of the outer wall and also eliminate excessive heat losses byv convection and radiation. It has generally been considered, however, impossible, from a practical standpoint, to support the refractory lining of the furnace in spaced relation to the outer retaining wall of the furnace setting due to the fact that the rate of expansion and contraction of the lining is very different from the rate of expansion and contraction of the zo retaining wall. p In ordery that a hollow wall construction for furnaces should be practical, it is necessary toprov'ide means for properly supporting the refractory lining in such manner as to permit expansion and contraction thereof independently of the outer retaining wall of the setting. This has generally been considered impossible. I have found, however, that providing suitable anchoring members it is possible to construct 3u a hollow wall including arefractory lining or inner wall spaced away from the outer retaining wall and supported in such manner as to have independent expansionand contraction.` '1 v '35. One of the main objects of the invention the outer wall.v A further object is to pro` vide means for supporting the innerwall in such manner that the lower edge of this inner wall can be disposed in proper relation to the f re zone or the grate structure ofthefurnace.,

ing the inner or liningV wall of refractory.

Further objects will appear from the detailed description.

rIn the 4drawings Figure l is a fragmentary vertical sectional view through a furnace wall constructed in accordance with my invention;

Fig. 2 is a fragmentary detail perspective view partly broken away, showing the connection between one of the wall anchors and one of the inner wall or lining supporting and anchor members;

Fig. 3 is a perspective detail, partly broken away, of one of the outer or retaining wall anchors and the connection between the same and one of the inner wall or lining holding anchors;

' Fig. 4 is a section taken substantially on line lr-t of Fig. 1;

Fig. 5 is a vertical fragment-ary sectional View through a conventional form of furnace showing a wall construction in accordance with my invention, as applied; and

Fig. 6 is a view similar to Fig. 5 of a modified form.

The outer or retaining wall l of the furnace setting is formed of an outer thickness or layer 2 of unvitriied brick such as is commonly used for this purpose, and an inner layer or thickness 3 of fire-brick of known type. An inner or lining wall 4 of refractory material is disposed in spaced relation to the inner face of wall 1, leaving an air space 5 between the two walls. The wall 4 is formed fromrefractory material which, when applied, is in a stilf plastic condition, this material being applied in lumps or chunks which are beaten together by a suitable mallet to forni a monolithic structure completely free of all seams or joints. This material, as stated, is in a sti' plastic condition so that the wall can be erected without a retaining form other than a suitable backing 6 which defines the outer face of the wall and provides a support against which the wall is formed, as will be obvious. As the wall 4 is of monolithic construction, it can be supported by suitable members from the outer wall l in such manner as to be capable of independent expansion and contraction. This is an important feature of my invention,

as it is not possible, from a practical standpoint, to support an inner lining Wall from an outer retaining wall for independent expansion and contraction and in spaced relation thereto, unless the inner wall is of monolithic construction. In a wall formed of bricks or tiles of refractory material, itis necessary to employ a suitable bonding materiale-r mortar between` thejoints and this material quickly disintegrates under the inuence of thehightemperaturesdevelopedin the furnace with the result that openings are quickly formed through the refractorywall, thus destroyinggto a large extent, its usefulness and causing, within a comparatively short time, the collapse and consequent destruction of the wall. Thisis particularly true where the refractory or inner lining wall is supported from the outer retaining wall in spaced relation thereto, as in applicants construction. Infact, it has been considered impossible heretofore to so support an inner refractoryor liningwall. c

The `wall 4 is supported by supporting and i anchoring brackets 7 of substantially V-shape formed from a single strip of strap metal bent to -provide an upper horizontal arm8, alower'inclined arm 9 disposed at. an acute langle yto arnrS, anda short horizontal element 10 extending from the lower end of arm'9. At the apex of the vbracket 7, the

materiallis bent back upon itself to forman upwardly extending finger 1,1 disposed at right angles to arm 9. The arms V8 and 10 extendthrough Ysuitable openings 12 provided metal. l

rlheouter end of arm 10 is provided with a transverse slot 13 formed by slitting the metal and turning the same downwardly to form a depending flange14, the end portion of arm 1() being turned upwardly to form an upwardly extending flangel. Slot 13 rein the backing 6, which is vpreferably of sheet ceives the inner end arm 16A of a U-shape anchor 16 whichv is anchored in wall l, as illustrated. The outer vend of arm 8 is similarly secured to the outerwall. The brackety or member 7 isthus secured to the outerl wall` in such manner as'to be capable of supporting a great weight `while permitting independent expansion and contraction of the inner wall 4 Vdue to therelative vertical and transverse movement between the arm of member 7 and the anchor members 16,*slot 18V being of greater Ywidth than arm 16A, as illustra-ted in f Figure 2. The members l7, due to their truss construction, possess great Strength @millor this reason are employed aS vhangers or supporting members for `carrying' the weightof g ce . limited byy headers -17 in the form of bricks the wall 4 and supporting the same from Wall 1. Movement of wall 4 towards wall 1 is extending from the inner layeriB of wall 1, theseheaders contacting with the inner face ofthe sheet metal backing ,6 and kforming abutment elements for the outer face of wall 4. Holding anchor members 17a of elongated U-shape arel imbedded in wall 4 and extend through openings 18 in the backing 6. Themember 17a is provided, adjacent its outerend, with a transverse slot 18k and flanges 19 and 20. This slot receives arm 16A` of the outer wall anchor 16, member 17 a beingthus connected to anchor 16Y in the same ymanner as the arms. of` member 7 are Vconnected to their respective anchors. The

123,825; and the particular construction-of the member 7 and associated anchors 16 and the connections between the same are disclosed' in detail in my copending application for kiiexible anchor filed November 1,4 1926, Serial No. 145,466. x Y

In practice, the wall 4 is of proper height to suit the particular furnace and conditions ofk use thereof. f The positionof the bottom of lwall 4 will also bevaried to suit the circumstances.l In Figs. 5 and 6, I have illustrated a conventional form offurnace construction showing the wall 4 as extending ,below the grate 21. In F ig. 5, the air space v5 is open at its lower end thus permitting the relatively cool air which enters beneath the grate to flow upwardly through space 5, this :air being heated to a certain extent from the refractorylining wall 4 land* the'passage of 'the' air upwardly through the spacesl 5 eectually preventing heating of the retaining wall 1. In the-modified form illustrated in Fig. 6, the :lower ends of the air spaces 5A are closed by flanges 4A formed at the lower ends of the walls .4. This provides dead air spaces between the inner-and the outer walls which serve to eifectually insulate the same andprevent heating toY any appreciable extent ofthe outerY retaining walls'. In other types lof furnaces in which grate structures are not employed, as in furnaces using oil or gas for fuel, the yposition of the 'lo-wer ends ofthe Vlining `wa'lfls and the Vheight .of these walls will be varied to suit conditions, as Willbe readily understood by those experi-A enced inthe art. Y f In erecting the wall 4, suitable strips or' sheets of sheet metal are placed-in position against thev headers 17; which ser-veto effectually supporttheV backing 6 thus formed,

these headers doing away with any-necessity rfor employing studding or other means for supporting the. backv 6, :though studdings 'y i may be employed when desired or necessary,

these studdings being formed of wood and being burned out in the use of the furnace. After the walls 4 have been erected in the manner described, they are suitably dried and 'vitriiied and the furnace is then in condition vfor use. In use of the furnace, the sheet metal backing 6 will eventually become oxidized and will disintegrate, after which the outer face of wall 4 will be in direct contact 'with the headers 17 What I claim is :-V Y 1. In a furnace construction, an outer retaining wall, an inner refractory lining wall spaced from said outer wall, anchor members secured in the inner wall, and anchor members secured in the outer wall and having tongue and slot connections with the inner wall anchor members for supporting the inner wall in spaced relation to said outerwall while permitting expansion and contraction of said inner wall in every direction in its plane independently of the outer wall.

2. In a furnace construction, a vertical retaining wall, an inner vertical lining wall disposed in spacedy relation to the retaining wall, anchor members in the retaining wall, anchor members in the lining wall, means holding the lining against movement toward the retaining wall while permitting freedom of expansion and contraction ofthe lining, and connections between the retaining wall anchor members and the lining anchor members preventing movement of the lining away from the retaining wall while permitting eX- pansion and contraction of the lining in every direction in its plane.

3. In a furnace construction, an outer retaining wall, an inner refractory lining wall n spaced from the outer wall, anchor members p `1y of the outer wall.

embedded in the lining wall, and anchor members embedded in the outer wall and having universal connection with the lining wall' anchor members, whereby the lining wall is free to expand and contract in every direction in the plane thereof independent- 4. In a furnace construction, an outer wall,

'a monolithic inner lining wall spaced from the outer wall, anchor members embedded in the outer wall, anchor members embedded lin the inner wall, and tongue and slot connections between the anchor members per- Amitting expansion and contraction of the inner wall in every direction 1n the Plane thereof independently of the outer wall.

In witness whereof, I hereunto subscribe my name this 15th day of November, 1926.

Y JOHN E. ANDERSON.

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