US2673534A - Support for refractory lined furnace doors or the like - Google Patents

Description

March 30, 1 G. L. ROBINSON 3,

SUPPORT FOR REFRACTORY LINED FURNACE DOORS OR THE LIKE Filed Jan. 18, 1951 2' Sheets-Sheet 1 INVENTOR GEORGE L. ROBINSON March 30, 1954 G 1 RQBlNSON 2,673,534

SUPPORT FOR REFRACTORY LINED FURNACE DOORS OR THE LIKE Filed Jan. 18 1951 2 Sheets-Sheet 2 INVENTOR GEORGE L. ROBINSON gy IWQFW Patented Mar. 30, 1954 SUPPORT FOR REFRACTORY LINED FUR- NACE DOORS OR THE LIKE George L. Robinson,

Pittsburgh, Pa., assignor to Blaw-Knox Company, Pittsburgh, Pa., a corporation of Delaware Application January 18, 1951,

Serial No. 206,630

6 Claims. (Cl. 110173) This invention relates to replaceable and dethat is, anchor members for refractory lined furnace doors or the like. More particularly, it pertains to a retaining member and replaceable or detachable anchor stud combination for the plastic refractory lining and peephole ring respectively of furnace doors such as those used on open-hearth furnaces. Reference is hereby made to my copending United States patent application Serial No. 118,336 filed September 28, 1949.

It is customary to line water-cooled furnace doors with a plastic refractory cast in the hollow fractory, the studs being secured to the face of the door by some means. The refractory lining and the studs are consumed or eroded away by action of the hot furnace gases, and require replacement after about one to three months of service. The furnace door itself may last about four to five years before it must be replaced. A typical steel mill may have about ten to twelve furnaces, each with five doors. If these doors require relining at about six weeks intervals, it is evident that about nine or ten of these doors may have to be relined each week. It is apparent, therefore, that a new construction and manner of fastening anchor studs which increases the ease and economy of re-studding and re-lining a furnace door is important.

Various means for securing such studs to the door have been suggested and used. Assuming such studs have the same material and spacing, they are believed to give comparable performance during the time the door is on the furnace. However, they are not as satisfactory as the replaceable supports of this invention insofar as case and cost of "replacement are concerned. Thus, the most common practice is to weld one end of the stud to the face of the recess in the door. When such a door is to be relined the residual ends of the consumed studs must be burned or clipped off at the door face. Such preparation for the welding on of new studs, as well as the welding itself, is expensive. Qther fastenings for studs, not 'requiring welding, have also been suggested. Some of these involveholding a rearward extension of the stud in the hollow water-cooled body of the door, and are not only relatively high in cost but impose restrictions on the door construction to accommodate the dee siredv stud: spacing. -Others,, such as. nuts nently welded to the face of the door into which permastuds with threaded ends are screwed, have proved impractical due to the difficulty of removing the stub-end of the burned-down stud from the nut. None of the prior devices has been wholly satisfactory and some better solution to the problem has long been desired.

Similarly, a problem has arisen relative to the fastening of the peephole extensions within the refractory lining spaceof furnace doors such as those for open-hearth furnaces. These peephole extensions are frequently'in the form of pipe sections arranged in coaxial registry with the peephole ring through the hollow water-cooled body of the door. They thereby protect the edge of the refractory around the peephole itself particularly when taking samples through the peephole and, with plastic refractory linings, serve as a casting form during the casting of the lining. A common method of fastening the peephole extension has been to'weld it to the furnace door at the back of the lining recess thereby making it a part of the structure of the door. In service the peephole extension will burn away in part at least. Hence, when the door is relined, replacement of the peephole extension is usual.

chipping out the weld thereof to the door and then the door is sent to the welding department where a new peephole extension is welded in place. As a consequence, the water-tight integrity of the body of the door may be impaired and, in any event, the door remains out of service for a relatively considerable period of time and involves the expense of handling and treatment which has been outlined by skilled workmen.

The instant invention overcomes the foregoing difiiculties in that the retaining members are permanent and trouble-free and the anchor members are readily detachable and replaceable movement in the structure of the door which may occur in operation. Further, the retaining and anchoring members which are made in accordance with this invention are readily applied to a wide variety of furnace doors; involve no larger repair problem when the relining orpeephole replacement thereof is in order; and-permit the same unskilled workmen,'who are to'renew the lining, to replace the burned studs and such peephole extension quickly and effectively before the new lining iscast.-.. t x

Other objects and advantages; of, this invention will he apparentv from the following description and the drawings, which are illustrative only, in which Figure 1 is a view in elevation of a furnace door employing the combination of this invention;

Figure 2 is a vertical cross sectional view taken along line 1I--II of Figure 1 and showing a portion of a plastic refractory lining in place;

Figure 3 is a horizontal cross sectional view taken along line III-III of Figure 1;

Figure 4 is a view in front elevation of an embodiment of this invention applied to the supports for a plastic refractory lining;

Figure 5 is a view in side elevation of the embodiment of Figure 4 taken along line V-V of Figure 4 through the retaining member;

Figure 6 is a plan view of the embodiment shown in Figure 4;

Figure 7 is a view in front elevation of a modifled embodiment of this invention applied to the supports for a plastic refractory lining;

Figure 8 is a view in elevation of the modified embodiment shown in Figure 7 taken along the line VIII-VIII of Figure 7 through the retaining member;

Figure 9 is a plan view of the modified embodiment shown in Figure 7;

Figure 10 is a view in front elevation of an embodiment of this invention applied in providing for a detachable and replaceable peephole extension for the furnace door shown in Figures 1 to 3;

Figure 11 is a view in elevation of the embodiment shown in Figure 10 taken along line XI--XI of Figure 10;

Figure 12 is a view in front elevation of a modified embodiment of this invention applied in providing for a detachable and replaceable peephole extension for the furnace door shown in Figures 1 to 3;

Figure 13 is a view in elevation of the modified embodiment shown in Figure 12 taken along line XIIIXIII of Figure 12;

Figure 14 is a view in front elevation of a further modified embodiment of this invention applied in providing for a detachable and replacement peephole extension; and

Figure 15 is a view in elevation of the modified embodiment shown in Figure 14 taken along the line XV-XV of Figure 14.

The preferred embodiment of this invention applied to the supports for a plastic refractory lining and illustrated in enlarged view in Figures 4 to 6 inclusive is shown on the furnace door in Figures 1 to 3 inclusive. This furnace door is the subject of United States patent application Serial No. 613,073 filed August 28, 1945 in the name of Edward W. Pottmeyer, now Patent No. 2,547,229 dated April 3, 1951. Although the door of the said application Serial No. 613,073 is particularly useful in the practice of the instant invention, the instant invention may also readily be used with both solid and full panel type furnace doors.

In Figures 1 to 3, such a furnace door 10 has an inner wall I I, the inner side 12 of which comprises the face of the door against which a refractory lining I3 is periodically cast as each relining is performed. A hollow peripheral flange l4 extends around the outside of the door l0. These flanges have inner sides i 5 set at a slight angle to each other to form a dovetail fit with plastic lining 13. Wall H also has 'a rear or outer surface [6 against which water-coolin means are applied. These water-cooling means comprise a series of vertical channels 1? 71 .1%

intercommunicate with each other and with vertical flanges Ma through the horizontal flanges Nb of the hollow peripheral flange. Pipe nipples l8 welded to the top of door (0 respectively form an inlet and an outlet to the cooling water passages through door lll. Washout plugs 20 are threaded into tapped holes in blocks 2|, which tapped holes communicate with the cooling water passages in door H! at the bottom of the vertical rails Ha of flange M. A lifting yoke 22 and lugs 23 for conventional counterbalance cables afford a conventional arrangement for the raising and lowering of door It).

Peephole 24 and peephole extension 25 are metal ring sections in registry and together form an observation port through door In including the central channel H. A wearing plate 24a may be welded around the inside lower portion of peephole ring 24. A cover 26 normally rests against ring 24 and closes the port. Cover 26 is operated by means of a chain 21 in a conventional manner.

In the preferred embodiment of a plurality of retaining members or clips 30 is welded in a predetermined pattern to surface 12. This pattern may be varied so long as it furnishes the required support for a plastic refractory lining to be cast against surface l2 and the respective inner sides l5. Each retaining member 30 is in the form of a retaining member or socket of a material like sheet steel bent into the form of a longitudinal arch having a longitudinal central portion 31 spaced away from surface l2. This spacing is obtained by the divergence of two side portions 32 extending toward surface I2 so that the innermost side edges thereof may be welded to metal wall II. A U-shaped recess 33 is cut or punched through central portion 3| for a substantial portion of the length thereof downwardly from the top edge 34 of retaining member 30. Since central portion 3| and sides 32 are each relatively plane, the space between recess 33 and the lower part of portion 3i and surface 12 is relatively trapezoidal in configuration.

As a consequence, an anchoring member such as a stud 35 of steel, copper or other suitable metal having an outwardly flared or countersunk base 36 of greater diameter than the width of recess 33, can be held tightly against surface l2 by sliding it with body 36a substantially between recess 33 and surface I2. The base 36 of stud 35 is of a diameter which readily passes through recess 33 between the sides thereof so that it extends normal to wall ll into the space to be occupied by a lining 13. In practice, stud 35 is a rivet with a countersunk head, which head acts as base 36. In the formation as by bending of socket 30, the slope of sides 32 is generally similar to the flaring of the sides of base 36. Thus, as shown in Figure 6, the inner edge 31 normally bears against base 36 to insure a proper fit be tween stud 35 and socket clip 30.

Because of the arch shape of retaining member 30, it is open at the top and at the bottom as shown in Figure 5. Any refractory or other material which may accumulate around base 36 within socket 30 during use is readily removable either when the stub end of stud 35 is removed or thereafter. Such stub ends can readily be removed by knocking them up by hammer blows and out of their respective sockets 30. Any other material between sockets 30 and wall H can be dislodged by further blows or by poking the materialout with a chise'l. Thereafter, new studs;

35 may be'knocked into place bymo'ving them downwardly in recess 33 generally parallel to wall -I I. Although the rearmost portion ofthe-socket's 30 is illustrated as surface l2, such'sockets may, if desired, be provided with back plates of their own which back plates can then be welded to wall -II to form the combination of this invention. Further, although the recesses 33 are illustrated as being U-shaped in vertical position, various departures from such shape and orientation may be made in particular cases.

It is evident that socket blanks which may be steel or other suitable metal can be stamped out or otherwise cut and recessed and bent very quickly and inexpensively. Such sockets would then be welded in a predetermined pattern to the particular furnace door to be used. In the case of full panel type doors using box-type panels with vertical spaces between or in the event there are observation openings for the refractory lining through the back of the door and through a wall portion corresponding to wall I l, suitable blanking off pieces can be used to fill such spaces during the casting operation while the refractory lining is still plastic. Subsequently, such blanking olf pieces may readily be removed. In using a furnace door of the type illustrated in the afore said application Serial N 0. 613,073, the pattern for the sockets 30 need not make any allowance for the immediate presence of water cooling means directly in back of the respective socket on the other side of wall I 1. Thus, as shown in Figure sockets 30 may be directly in front of a channel I! or directly in front of the space between adjacent such channels or directly in front of the flange of a channel affixed to surface 16. w

As the lining I3 is consumed or eroded away, the studs 35 also progressively burn away. However, the studs are not completely consumed since a short stub end will remain even though the linin around it is completely consumed. It has been found in tests of the improved stud and fastening of this invention that no fusing of such stub end to its anchor socket, such as socket 30, occurs on such exposure although the exposure may be prolonged for a substantial period of And despite such exposure, the stub end is still easily removable and the socket remains in good condition indefinitely for the reception of new studs when are usually relined before metal plate II is exposed, but it occasionally occurs. Thus, it is a further important advantage of this invention that the time of relining is not critical in relation to the functioning of the device of this invention.

When such a door is to be relined, an unskilled workman can readily hammer the old studs 35 out of the sockets 30 and similarly dislodge any hardened refractory or other material which may have collected around base 36 in socket 30. Such dislodgment is facilitated by the open bottom of socket 311 permitting the material to fall free where it can be swept away. The insertion of new studs 35 is then readily accomplished by sliding them into placewith the aid ofsuch hammer blows as may be required. A rigid pattenfiof new anchor members is thus quickly obtained for the new lining which can then be cast.

In Figures '7 to 9 inclusive, a modified retaining member 49 is shown, which is adapted tobe welded to the face of the door along each side and its bottom edge as form. A recess 4| .is provided between the slopwell, which is conical in outer edge of peephole ing sides and conical'bottoni 'of the retaining member 40, which recess accommodates a stud 42 which is identical with stud 35. The rearwardly extending edge of retaining member 40 is welded to a wall surface such as wall H and functions substantially as the previously described retaining member 30 functions except that socket 40 has no bottom opening for the convenient dislodgment of caked or accumulated material. However, it has the added advantage of better distribution of the welded connection for conduction of heat to the wall I i.

In like manner to the provision of retaining and supporting members for anchoring and cooling the plastic refractory lining of furnace door l0, anchor members or studs 43 like studs 35 and 42 may be provided for the peephole extension 25. These studs 43 may be in the form of rivets having countersunk bases 44 welded around the outer periphery of peephole extension 25 with the shank or body 45 of the said studs 43 extendin axially relative thereto. By these means the countersunk bases 44 face surface 12 with the relatively flat ends of bases 44 substantially in a plane parallel to said surface l2 when ring 25 is in position for attachment to or detachment from inner wall ll. When so attached the fiat end of studs 43 will normally be against surface l2 placing studs 43 and ring 25 in heat-conducting relation to wall II for the cooling of said studs 43 and ring 25. If three studs 43 are provided, spaced equidistant around the outer periphery of peephole extension 25, three correspondingly spaced retaining members 46 are then also provided. These retaining members 46 may be substantially identical in character and functioning to retaining members 30 and are similarly welded to surface l2 as shown in Figure 11. Hence, if a bar 41 is inserted through the openings 43 provided therefor on opposite sides of rin 25 as shown in Figure 10, the peephole extension 25 may be attached to the furnace door by rotating it clockwise as shown in said Figure 10, from the dash and double-dot position of bar 41 to the dash and single-dot position thereof. Conversely, rotation in a counterclockwise direction as viewed in Figure 10 will detach the studs 43 from their respective retaining members 45. The bar 41 is removed after each new peephole extension is connected to door I 0. As in the case of the anchor members 35 and their respective retaining sockets 30, it is desirable to have a reasonably good fit between the studs 43 and the sockets 46. In such a fit, the flared end of the heads 44 will preferably bear against the surface l2 and either the flaring sides of the heads 44 or the body 45 of the studs 43 will be engaged by the edges 49 defining the recess in the respective sockets 45. In general, it is only necessary to move the studs 43 sufficiently far into said recesses to obtain the fastening engagement that is desired.

It will be noted that peephole 24 may be provided with an inner edge 241) which overlaps the extension 25 without being in any frictional contact therewith. Thereby, the attachment, detachment and replacement of peephole extensionssuh as extension 25, are facilitated while at the same time serving as lining forms around the peephole extending through rings 24 and 25 for the plastic refractory during the casting thereof in the initial lining or relining of the door I 0. V The modification illustrated iii-Figures 1-2 and I3 is similar in character and functioning to the embodiment own-,r ne tively n Fisu estlfl and 11 except thata flared or conical peephole extension 25 is employed.- The samerefersnce-numerals are applied to thecorresponding; parts of the modification-in Figures 12. and 13'with1the addition, however, of primes as are applied to the embodiment shown in Figures and-l1. It will be evident that as in the case of the studs 35 and 42, different forms of enlargedbases and different forms of bodies may be employed for anchor members 43, and similarly for retaining meme bers 46. For example, an equivalent retaining member might-be made in, two parts inspaced relation to achieve a socketof :the character disr closed herein. A peephole extensionmay also be provided in the support combination of-this invention, as shown in Figures 14 and 15, whereby instead of being rotated-into attached or de tached position, it may be translated or moved in a linear direction into attached or detached position. In such a case, all of the recesses, for example, in the retaining members 46-might ex: tend parallel to each other and with theiropen ends all facing in the same direction, sothat-a rectilinear movement of the stud bases, such as bases 44, would fasten such peephole, extension to the furnace door. In this last-mentioned arrangement, the ring corresponding to. '24- would not be provided with any overlapping edgeMb but would terminate substantially in the plane of inner wall II. Parts in Figures 14 and 15 simi: lar in character and functioning to the other embodiments are provided with the same reference numerals with a double prime factor added there to. i Various other modifications may be made which are within the spirit of this invention and the scope of the appended claims.

Iclaim:- L In a furnace door, in; combination,'a wall having a surface against which refractory is placed and a peepholethroug-h. said wall, aretaining member fastened to-said-surface of said wall adjacent the edge of-said peephole, said retaining member having a recess and a space between said recess and said surface, said recess and space having an entry end and extending generally parallel to said surface, said recess and space further being in communication with one another, an anchor member havin an enlarged portion generally of greater dimension than said recess and generally of lesser dimension than said space, said anchor member further having a portion of lesser dimension than said recess, and a peephole extension tubular member connected to said last-mentioned portion of said anchor member, said anchor member having its portion of lesser dimension extending in a direction axially of said tubular member and being adapted to have its portion generally other than said enlarged portion movedinto said recessed portion through said entry end to fasten said enlarged portion substantially in the space between said retaining member adjacent its said recessed portion and said wall, whereby said anchor member and peepholeextension tubular member are fastenedto saiddoor 2. In a furnace door; adapted to-be linedperiodically with a refractory, in combination, an in nor metal wall having a surface against which refractory is placed and a peephole extending through said wall, a plurality ofretaining members attached to said surface of saidwalkaround the d e. o said:pcenholazeach; of: said-retainin memb rsharmsarecesscxtendingeenerally pare allel-to said wall and a spacebetween saidrecess and said surface, said recess: and space having an open end and said recess be ng spaced from but generally close to-said surface of said wall, said recess and space further being in communication with one another, a plurality of anchor members each having an enlarged portion generally of greater dimensionthan said recess and generally of lesser dimension than said space, each of said anchor members further having a body of lesser dimension than said recess, each of said anchor members being adapted. to have its portion generally other than said enlarged portion moved into said respective recess and space portions through said open end in a direction generally parallel-to said wall, said enlarged portion being fastened substantially in the spacebetween its respective retaining members adjacent its said recess and saidwall, and a peephole extension tubular member connected to said body of said anchor members, said body between said peephole extension tubular member and said enlarged portion of saidanchor members extending in a direction axially of said tubular member, whereby-said anchor members and peephole extension tubular member are detachably fastened by said retaining membersto said door. Y I

3. In a furnace door tobe refractory lined having a peephole, in combination, a wall having a metal surface against which-said refractory is placed and through which said peephole extends, a plurality of sockets each welded to said wall at said surface and around the edge of said peephole, said sockets each having a central portion spaced from said surface, said central portion having a narrower recess extending inwardly from a corresponding edge of said sockets and substantially parallel to said surface, said sockets each defining a space between said recess and said surface with said recess in communication with said space, a plurality of studs each having an enlarged base and a portion connected thereto which is narrower than said recess, said enlarged basebeing of greater dimension than said recess but of similar lesser dimension than the space between said central portion and said wall when the portion of said stud generally other than said enlarged base is slid into its respective recess with: the axis of said stud substantially normal to said surface, and a peephole extension tubular member connected to said last-mentioned portion of said studs. I

4. In a furnace door adapted to be lined periodically with a refractory, in combination, a

wall having a, substantially continuous metal surface against which said refractory is placed and a peephole through-said wall, a plurality of sockets attached to said wall in a predetermined pattern around the edge of said peephole, said sockets having generally U-shaped recesses therein extending generally parallel to said wall, said recesses being smaller than the area co ered by the perimeter of said sockets at said surface to provide a space between said recesses and said wall widening toward said wal1,..each of said recessesand-its respective. space "being in communication with one another, said recesses generally facing in the same direction on'a circle circumscribed about the center of said peephole, a plurality of studs each having a flared base larger than said recesses, said flared base being generally similar in cross section to but somewhat smaller-than therspac'e between" said-recesses and said. well. said studs further having shanks of a size which will extend through said recesses, and a peephole extension tubular member connected said shanks of said studs,

5. In a furnace door to be refractory lined, in combination, an inner wall through which a peephole extends, said wall having a surface against which refractory is placed, a plurality of openended recessed sockets permanently fastened to said surface of said inner wall in similar spaced relation around the edge of said peephole, said sockets having their respective recesses parallel to and spaced from said inner wall and extending studs each body, said flared base having a dimension greater than said recess but less than the space between said recess and said surface so as to fit and be retained by its respective said socket with the body of said stud extending through said recess in said socket generally normal to said inner Wall, the aforesaid edges of said sockets facing in a direction such that one continued movement will engage said flared bases generally between said sockets adjacent said recesses and said wall, said body having a size which will pass through its respective recess, and a removable peephole extension tubular member coaxial with said peephole and rigidly connected to the respective bodies of said studs in an axial direction around the periphery of said peephole extension tubular member, the peripheral spacing of said studs being substantially equal to the respective spacing of said sockets.

6. In a furnace door to be refractory lined, in combination, an inner wall having a peephole 10 therethrough, said wall having a surface against which refractory is placed, a removable peephole extension tubular member having a diameter at least as large as the diameter of said peephole, axially extending anchor members each having a body welded to the outer periphery of said peephole extension tubular member, said anchor members being angularly spaced from each other and having an enlarged base extending beyond said peephole extension tubular member toward said inner wall, said enlarged bases respectively having flat ends generally lying within a single plane, retaining members equal in number to said anchor members connected to said surface of said inner wall and spaced around said peephole corresponding to the spacing of said anchor members, said retaining members having recesses spaced from said inner wall and extending inwardly from one edge of said respective retaining members in a direction parallel to said wall, each of said retaining members defining a space in communication with said recess, said space being between said recess and said surface, said recesses lying on a circle circumscribed about the axis of said peephole extension tubular memdetached from said furnace door with said fiat ends substantially against said inner wall.

GEORGE L. ROBINSON.

References Cited in the file of this patent UNITED STATES PATENTS

Images