US2673533A - Replaceable support for refractory lining of furnace doors - Google Patents

Description

March 1954 e. L. ROBINSON 2573,5153

REPLACEABLE SUPPORT FOR REFRACTORY LINING OF FURNACE DOORS Filed Sept. 28. 1949 2 Sheets-Sheet 1 INVENTOR Geo/9e L. Robinson moons March 1954 G. L. ROBINSON REPLACEABLE SUPPORT FOR REFRACTORY LINING OF FURNACE 2 Sheets-Sheet 2 Filed Sept. 28. 1949 lNVENTOl? George Lfiobmson lwud Patented Mar. 30, 1954 UNITED STATES PATENT OFFICE Animation September 28, 1949, Serial No. 118,336

1 4 Claims.

This invention relates to replaceable supports, that is, anchor members for the refractory lining of furnace doors. More particularly, it pertains o a socket and replaceable anchor stud combination for plastic refractory lined furnace doors such as those used on open-hearth furnaces.

It is customary to line water cooled furnace doors with a plastic refractory cast in the hollow recess of the door, and to secure the lining to the door by means of metal studs projecting from the face of the door and embedded in the refractory, 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 iive 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 week intervals, it is evident that about nine or ten of these doors may have to be relined each week. It is 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 i 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 re- .placeable supports of this invention insofar as ease 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 clipp d 011 at the door face. Such preparation for the welding on of new studs, as well as the welding itself, is expensive. Other fastenings for studs, not requiring welding, have also been suggested. Some of these involve holding a rearward extension of the stud in the hollow watercooled body of the door, and are not only relatively high in cost but impose restrictions on the door construction to acccate the desired stud spacing. Others, such as nuts permanently welded to the face of the door into which studs with threaded ends are screwed, have proved impractical due to the difllculty of removing the stub-end of the burned-down stud from the nut. None or the prior devices has been wholly satisrectory and some better gsclution to the problem has 1}? both The instant invention overcomes these difiiculties in that the anchor members are readily replaceable despite any bending or 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 thereof is in order; and permit the same unskilled workmen who are to renew the plastic lining to replace the burned studs quickly and effectively before the new relining is cast.

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

Figure 2 is a vertical cross sectional view taken along line 11-11 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-J11 of Figure 1;

Figure 4 is a view in front elevation of a preferred embodiment of this invention;

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

Figure 6 is a plan view of the preferred em bodiment shown in Figure 4;

Figure 7 is a view in front elevation of a modifled embodiment of this invention;

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

Figure '9 is a plan view of the modified embodimont shown in Figure '7.

The preferred embodiment of this invention illustrated in enlarged view in Figures 4 to 6 inelusive is applied to the furnace door shown 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. 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 In has an inner wall II, the inner side I2 of which comprises theface oi the door againstwhich aplastlc "refractory lining i8 is periodically can as each relining is erformed. A hollow peripheral flange [4 extends around the outside of the door Ill. These flanges have inner sides l5 set at a slight angle to each other to form a dovetail fit with plastic lining l3. Wall II also has a rear or outer surface l6 against which water-cooling means are applied. These water-cooling means comprise a series of vertical channels I! which intercommunicate with each other and with vertical flanges Ila through the horizontal flanges Nb of the hollow peripheral flange. Pipe nipples l3 welded to the top of door l0 respectively form an inlet and an outlet to the cooling water passages through door I (I. A vent nipple I9 is also provided for door II) with access to the water cooling passages therein. Washout lugs 23 are threaded into tapped holes in blocks 2|, which tapped holes communicate with the cooling water passages in door in at the bottom of the vertical rails a 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 Hi.

Rings 24 and 25 are in registry and together form an observation port through door it including the central channel II. 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 a plurality of retaining members 33 is welded in a predetermined pattern to surface II. This pattern may be varied so long as it furnishes the required support for a plastic refractory lining to be cast against surface I2 and the respective inner sides I5. Each retaining member 30 is in the form of a socket of a material like sheet steel bent into the form of a longitudinal arch having a longitudinal central portion 3| spaced away from surface l2. This spacing is obtained by the divergence of two side portions 32 extending toward surface 12 so that the innermost side edges thereof may be welded to metal wall I l. 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 socket 30. Since central portion 3| and sides 32 are each relatively plane, the space between recess 33 and the lower part of portion 3| and surface I2 is relatively trapezoidal in configuration.

As a consequence, an anchoring member such as a stud 35 having an outwardly flared or countersunk base 36 of greater diameter than the width of recess 33, can be held tightly against surface i2 by sliding it with body 36a substantially between recess 33 and surface '2. The base 35 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 l3. In practice, stud 35 is a rivet with a countersunk head, which head acts as base 38. 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 between stud 35 and socket 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 r socket on the other side of wall ll.

and out of their respective sockets 30. Any other material between socket 30 and wall II can be dislodged by further blows or by poking the material out with a chisel. Thereafter, new studs 3'5 may be knocked into place by moving them downwardly in recess 33 generally parallel to wall ll. Although the rearmost portion of the sockets 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 1 I 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 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 I, 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 ofi pieces may readily be removed. In using a furnace door of the type illustrated in the aforesaid application Serial No. 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 Thus, as shown in Figure 3, sockets 30 may be directly in front of a channel II or directly in front of the space between adjacent such channels or directly in front of the flange of a channel aflixed to surface I6.

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 lining 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 time. 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 the door is to be relined. Such severe exposure is not usual because furnace doors 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 plastic or other material which may have collected around base 35 in socket 36. Such dislodgment is facilitated by the open bottom of socket 33 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 place with the aid of such hammer blows as may be required. A rigid pattern of new anchor members is thus quickly obtained for the new lining which can then be cast.

In Figures '1 to 9 inclusive, 9. modified mist 40 is shown substantially in the form of one-half of a conical washer. A recess 41 is provided by the opening in such washer which recess accom modates a stud 42 which is identical with stud 35. The rearwardly extending edge of socket 40 is welded to a wall surface such as wall II and functions substantially as socket 30 functions except that socket 40 has no bottom opening for the convenient dislodgment of caked or accumulated material. Moreover, socket 40 offers somewhat less support to the anchor members than does the preferred embodiment socket 30.

The particular shape and orientation of the retaining members and of the recesses therein and of the locking space defined thereby for a generally corresponding cross section of the cooperating anchor members are matters which may be widely varied and still be within the spirit of this invention as defined by the scope of the appended claims.

I claim:

1. In a plastic refractory lined furnace door, in combination, a wall having a face against which refractory is placed, a socket permanently fastened to said face, said socket having a portion close to but spaced from said face, said portion having a recess therein, a stud having a body and a base, said body having a width less than the width of said base, said recess having a width less than the width of said base but greater than the width of said body, said base having a length movable between said face and said portion to hold the remainder of said stud extending through said recess normal to said face to anchor said refractory.

2. In a plastic refractory lined furnace door, in combination, a wall having a face against which refractory is placed, a plurality of sockets permanently fastened to said face. each of said sockets having a central portion closely parallel to but spaced from said face and side portions extending between said central portion and said face, said central portion having a recess therein, a stud for each of said sockets, each stud having a body and a base, said body having a width less than the width of said base, said recess having a width less than the width of said base but greater than the width of said body, said base having a length approximating the distance between said central portion and said face, said stud being slidable parallel to said face with its axis perpendicular thereto and into said recess with said base between said central portion adjacent said recess and said face to hold the remainder of said stud extending through said recess and normal to said face to anchor said refractory.

3. In a plastic refractory lined furnace door. in combination, a wall having a surface against which refractory is placed, a retaining member having a central portion closely parallel to but spaced from said surface and side portions extending between the sides of said central portion and said surface, the edges of said side portions adjoining said surface being permanently aflixed to said wall at said surface, said central portion having an end spaced from said surface, said central portion further having a recess forming a slot extending to said end, a stud having a body and base, said base being wider than said body and said recess, said recess being wider than said body, said base removably fitting between said central portion, said side portions and said surface to hold the remainder of said stud extending through said recess normal to said surface to anchor said refractory.

4. In a plastic refractory lined furnace door, in combination, a wall having a surface against which refractory is placed, a plurality of sheet metal sockets and metal stud anchors for said refractory, each socket being welded to said wall at said surface, said socket having a central portion closely parallel to but spaced from said surface and side portions extending between said central portion and said surface, said central portion having upper and lower edges spaced from said surface and a recess forming a slot extending downwardly from said upper edge, a stud for each socket having a body and base, said base being wider than said body and said recess, said base further having a length generally equal to the distance between said central portion and said surface, said recess being wider than said body, said base being slidable parallel to said surface and between said central portion and said surface to hold the remainder of said stud extending through said recess normal to said surface to anchor said refractory.

GEORGE L. ROBINSON.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 282.846 Cole Aug. 7, 1863 488,851 Stock Dec. 27, 1892 614,177 McBride Nov. 15, 1898 739,326 Leonard Sept. 22, 1903 1,127,596 Crabiel Feb. 9, 1915 1,588,566 Wismer June 15, 1926 1,951,115 Wonsowicz Mar. 13, 1934 1,953,856 Heyman Apr. 3, 1934 2,037,018 Hall Apr. 14, 1936 2,063,261 Mees Dec. 8, 1936 2,103,106 Yurkovitch Dec. 21, 1937 2,124,425 McAfoos July 19, 1938 2,127,973 Isett Aug. 23, 1938 2,325,945 Fuchs Aug. 3, 1943 2,395,757 Peters Feb. 26, 1946 2,477,161 Ausland et al July 26, 1949 2,513,626 Corriston July 4, 1950

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