US2725855A - Doorframe for open-hearth furnaces or the like - Google Patents

Description

Sheets-Sheet l Dec. 6, 1955 E. w. POTTMEYER DOORFRAME FOR OPEN-HEARTH FURNACES OR THE LIKE Filed Oct. 13, 1950 Q N J P mm E W MZ/ w a M a JWW Jww f Dec. 6, 1955 E. w. POTTMEYER DOORFRAME. FOR OPEN-HEARTH FURNACES OR THE LIKE 2 Sheets-Sheet 2 Filed Oct. 13, 1950 WWW ZW M i M United States Patent DOORFRAME FOR OFEN-HEARTI-I FURNACES OR THE LHCE Edward W. Pottmeyer, Pittsburgh, Pa., assignor, by mesne assignments, to Blaw-Knox Company, Pittsburgh, Pa., a corporation of Delaware Application October 13, 1950, Serial No. 189,953 7 Claims. (Cl. 122-499) This invention relates to water-cooled doorframes for open-hearth furnaces or the like. More particularly, it relates to novel means for stiifening the legs of such frames to prevent the deformation or deflection thereof in the course of the use of such frames.

Doorframes provided for open-hearth furnaces, for example, receive severe use in the course of their lives. As a consequence, it is a common occurrence to have to remove and repair such doorframes one or more times during the life of the particular furnace structure with which they may be used. Because of the high temperatures to which such frames are exposed, at least in part,

the leg sections thereof are hollow for the circulation of cooling water to minimize the deterioration that would otherwise occur. An observed phenomenon during the course of the use of conventional doorframes has been that the leg sections forming the jambs thereof tend to curl inwardly toward each other more or less in the plane of the frame. Doorframes when newly installed have straight leg sections and are relatively loosely connected to the furnace framework for ready repair or replacement as required. At the same time, a reasonably close fit with the associated parts of the furnace structure is required in order to maintain economy and precision of operation. Hence, the aforesaid phenomenon of curling in which the jambs tends to deform or deflect into a somewhat bow-legged arrangement is detrimental. For example, such deflection can adversely affect. the closure between the doorframe and the furnace structure on one side or the door itself on the other. Further, such deformation may pinch the foreplate of the furnace structure so that the doorframe cannot readily be removed. If the clearance between the foreplate is less than the clearance between the door guides on a conventional doorframe and the door, such deformation may instead pinch the door at the bottom so that it cannot be operated.

In the past, a number of attempts to cure the problem of the deformation of the doorframe jambs has been made without any material success. Thus, various of the respective walls of the doorframe in the leg sections have been made heavier. In other cases, internal ribshave been applied along the outer walls of the leg sections of the doorframes. In all such cases, the phenomenon of curling appears to have continued.

By means of the novel provision of this invention, the foregoing curling and deformation difficulty has been overcome. Thus, doorframes employing the teachings of this invention can be installed and will'remain in service without objectionable curling or deformation of the leg sections common to prior doorframe structures. At the same time, the means of this invention retain efiicient heat conducting thin shell construction and provide increased metal surface cooling areas for improved operation. Moreover, the device of this invention is easily applied and relatively inexpensive. Other objects and advantages of this invention may be obtained from the following description and drawings, which are illustrative only, in which ICC Figure 1 is a view of a charging door assembly in an open-hearth furnace in which the new doorframe of this invention is employed;

Figure 2 is a view of the assembly shown in Figure 1 taken along line II II thereof; V

Figure 3 is a view or the assembly shown in Figure 1 taken along line III'III thereof;

Figure 4 is a view of a furnace charging door assembly using a modified doorframe made in accordance with the teachings ofthis invention;

Figure 5 is a view of the assembly shown in Figure 4 taken along line VV thereof;

Figure 6 is a view of the assembly shown in Figure 4 taken along line VIVI thereof;

Figure 7 is a horizontal cross section through a jamb of a doorframe of this invention showing a further assembly arrangement.

In an open-hearth furnace, for example, the assembly thereof comprising a charging door section may comprise a breastplate 10 extending between buckstays 11 on each side of the door opening 12. A skewback channel 13 is fastened to the framework of the furnace structure such as the buckstays 11 and supports a skewback refractory shape 14 which in turn assists in supporting the thrust and weight of an arched refractory roof 15. As shown in Figures 1 to 3, a doorframe 16 made in accordance with this invention is provided. This doorframe rests against the smooth front of the web of channel 13 and the front edges of the refractory walls 17 to either side of the opening 12.

Doorframe 16 may be relatively loosely held in place against the web of the buckstays as by resting on wedges placed on breastplate 10 on either side of the reduced central section of a foreplate 20, and by being attached by suitable means to the skewback channel or to buckstays 11. The eye members 18 welded to the top 19 of frame 16 are used when the frame is being placed in or removed from its operating position.' I

The doorframe16 is provided with generally vertical door guide flanges 21 at the sides thereof between which a furnace door 22, shown in dot-and-dash outline, may be slidably and vertically operated. Brackets 23' welded to the top of the door 22 enable suitable cable connections to be made for such operation of the door.

Doorframe 16 may beprovided with an integral cooling ledge 24 to protect skewback channel 13. The interior of the ledge 24 is in communication with the interior of top 19 through the openings 24a. In addition, generally rectangular integral leg sections 25 are provided in doorframe 16. These leg sections are hollow and form'the vertical jambs of the doorframe. In the embodiment shown in Figures 1 to 3, the guide flanges 2.1 are formed integrally with the walls of the jambs 25 and the interior thereof is in open communication with the interior of the jambs 25 and the interior of the top 19. Openings 26are drainage openings which are normally closed by pipe plugs. The top nipple connections 27 provide inlet and outlet openings respectively for pipe or hose connections whereby cooling water may be circulated through the interior of frame 16 and all parts thereof including the leg sections 25 and the ledge 24. Y

. Each leg section or jamb 25 has a hollow shell construction including a back wall 28 and a front wall 29, which is formed integrally with the inside and front wall of guide 21. In addition, each of such leg sections 25 is provided with an outer sidewall 30 and an inner side wall 31. The front wall of the respective guide flanges 21 merges at 32 with the main front wall of the jambs 25 above the foreplate 20.

The inner walls 31 of the jambs 25 define the width of the opening 12 through the frame 16. These inner walls 31 are bent flatwise or curve at 33 at their tops and extend inwardly toward each other to form the lintel 34 or bottom portion of the top 19 of the frame 16, completing the definition of the opening through the doorframe 16 with the reduced portion of the foreplate 20 between the bottom edges .of the jarnbs 25. It will be evident in view of the relatively close assembly required for best operation that any inward bowing of the bottom of the jambs 25 would if continued either pinch the foreplate 20 or the door 22. Howeven'in the frame 16 such inward curling is preventedin accordance with the teachings of this invention.

Thus, a solid elongated stiffener 35 is provided which is rectangular in section, the oppositesides of which are of unequal length or dimension. Each stiffener 35 is welded along one of its narrower sides or edges to the inside of the respective inner wall 31. Each stiffener 35 extends upwardly while so rigidly connected to the walls 31, from a point above the closed bottom of the leg sections 25 to the top 36 of the'stiffeners which are welded to the curves 33 along the same edge. The stiffener 35 is thus integrated with the leg at the point most remote from its neutral axis, substantially increasing itssection modulus while at the same time preserving the thin shell wall construction for effective thermal conductivity. The leg 'is not only much stronger but, by its relatively great thermal conductivity and increased area of contact with cooling water, it is readily kept at relatively low outside surface temperature in spite of the high furnace temperature to which the wall 31, in particular, is exposed.

As a consequence, theleg sections 25 of doorframe 16 will not become bow-legged or deflect or deform in the plane of the frame 16 and thereby develop the deficiency which exists in prior doorframes. By extending the stiffeners beyond the point of tangency of the narrow leg and the curve 33, into the upper body of the frame, the general rigidity of the structure is further increased. Moreover, such stiifeners 35 extend generally parallel to the back and front walls 28 and 29 respectively intermediate them where it can also in addition to its stiffening purpose provide additional effective cooling surface for contact with water being circulated through the leg sections 25. Thereby, the unimpaired operation and life of doorframes made in accordance with this invention may be vastly prolonged.

In the modification shown in Figures 4 to 16 inclusive, those parts thereof generally similar in .construction and purpose to corresponding Parts in the embodiment shown in Figures 1 to 3, are given the same reference numerals with the addition thereto of a prime. In doorframe 16 the hollow jambs 25' are provided with a stiffener 35' of a rectangular cross section having its opposite sides of unequal length. These stiffeners are respectively rigidly attached or welded along one of the narrower edges or sides to the inside of the inner walls 31 respectively. The stiffeners 35, extend from a point above the closure at the bottom of the leg sections 25' to a position above the beginning of the flatwise curve 33 at the top of each side 31'. The top end 36 of the .stiffeners 35' is bent fiatwise into substantially abutting relation with the front wall of top '19, said front wall being .a continuation and substantially in the plane of front side 29' of the legs 25'. The tops 36 are welded at .37 to said front wall to integrally attach the stilfeners 35' to the doorframe 16. Such connection at 37 assists the fastening between the adjoining narrow edge of stiffener 35 and the straight side of inner wall 31 to prevent deflection or curling of the legsections 25'. Instead of being fastened to the front wall of door frame 16', the top 36 of the stilfeners 35 may also be bent in the other direction and fastened to the back wall of the doorframe 16.

As shown in the embodiments -in Figures 1 to '6, the respective walls of the jamb sections 25 and 25 at least are made of angles for the generally vertical members. Thus, each jamb 25 has the walls 28 and 30 comprising one angle; the remaining exterior walls 'of guide flange 21 comprising another angle; and the walls 29 and 31 comprising a third angle in welded relation to each other as shown more particularly in Figure 3. A similar construction is provided for the exterior of the leg sections 25'.

However, in the assembly shown in Figure 7, a different arrangement is provided for the exterior of the vertical members of a leg section of a doorframe made in accordance with the teaching of this invention. In the Figure 7 assembly the inward portion of inner side wall 31" together with back wall 28" and outer side wall 30" are made of a single plate or strip bent in the manner shown. Similarly, the remaining exterior walls of guiding flange 21", the front wall 29" and the outward portion of inner side wall 31" are also formed from a single plate or strip shaped in the manner shown in Figure 7. A stiffener 35 is placed at the joint between the two exterior wall portions of the leg section 25" so that a single vertical weld 38 may be made joining the two exterior wall portions and the narrow adjoining edge of stiffener 35" at that location. The remaining adjoining edges of the exterior wall portions just described may be welded at 39 to complete the vertical structural portion of the hollow leg sections 25". In this Figure 7 modification, reference numerals therein bearing the double primes generally correspond to like numbered parts in the embodiments in the other figures.

Various modifications in the details of this invention will be apparent without departing from the spirit of the invention or the scope of the appended claims.

I claim:

1. In a doorframe for open-hearth furnaces or the like, walled hollow leg sections forming the jambs of said frame, an elongated stiffener integrally attached along one edge thereof to the inside of the inner side wall of each of said jarnbs, said stiffener extending longitudinally along said leg section and laterally into said section parallel to the plane of said frame for a distance less than the inside lateral dimension of said section, said stiffener having a greater resistance to deflection in said plane than transverse to said plane.

2. In a doorframe for open-hearth furnaces or the like, walled hollow leg sections forming the jambs of said frame, an elongated stiffener integrally attached along one edge to the inside of the inner side wall of each of said jambs, said stiffener extending longitudinally along said leg section and laterally into said section for a distance less than the width of each of said jambs respectively and parallel to the plane of said frame, said stiffener further having its greatest resistance to deflection in said plane.

3. In a doorframe for open-hearth furnaces or the like, hollow leg sections having walls forming the jambs of said frame, said jambs having their inner side walls generally normal to the plane of said frame and defining the width of the opening therethrough, and an elongated solid stiffener attached along one edge in generally vertical position to the inside of each of said inner side walls of said jambs respectively and intermediate the front and back of said jambs, said stilfeners having a greater resistance to deflection in said plane than transverse to said plane and extending laterally into said sections for a distance less than the width of said jambs respectively and generally parallel to said plane.

4. In a doorframe for open-hearth furnaces or the like. hollow leg sections forming the jarnbs of said frame, each of saidjambs having an inner side wall generally defining a portion of the opening through said frame, a solid elongated stiffener of rectangular section welded along one narroweredge to the inside of said respective inner side walls in vertical position intermediate the front and back of said jambs, said stiffeners extending around at least a portionof the curve at the top of said respective inner side walls, said stiffeners further having their respective upper ends separated substantially by the Width of said opening.

5. In a doorframe for open-hearth furnaces or the like, hollow leg sections forming the jambs of said frame, the inner side wall in each jamb defining a portion of the opening therethrough, said side walls being bent inwardly toward each other at the tops thereof to form the lintel of said frame, and a solid elongated stiffener of rectangular section Welded to the inside of each of said inner side walls generally parallel to the front and back of said frame and intermediate the same, said stiffeners extending laterally for a distance less than the inside lateral dimension of said leg sections, one of the narrower of the sides of said stilfeners being welded to said respective side walls and oriented as above described, said stifieners further extending around and attached to at least a portion of the curve in said respective side walls at the top thereof.

6. In a doorframe for open-hearth furnaces or the like, hollow leg sections forming the jambs of said frame, said jambs having front and back walls respectively connected by an inner side wall, said inner side walls defining a portion of the opening through said frame, and a plurality of elongated solid stilieners having unequal dimensions in section, one of said stiffeners being integrally fastened along the narrower of said dimensions to the inside of each of said respective side Walls between said front and back walls, said stiffener-s extending upwardly for at least a major portion of the length of said jambs and terminating below the top of said frame.

7. In a doorframe for open-hearth furnaces or the like, hollow leg sections forming the jarnbs of said frame, said jambs having front and back walls respectively connected by an inner side wall, said inner side walls curving toward each other at the tops thereof to form the lintel of said frame and define the opening therethrough, and an elongated solid stiffener of rectangular section having opposite sides of unequal dimension, said stiffener being welded along one of said narrower sides to the inside of each of said respective inner side walls between said front and back walls, the upper ends of said stiifeners being welded to one of the aforesaid walls parallel to the plane of said frame.

References Cited in the file of this patent UNITED STATES PATENTS 125,777 Wood Apr. 16, 1872 495,428 McDaniel Apr. 11, 1893 918,356 McKennon et a1 Apr. 13, 1909 1,117,649 Edgerton Nov. 17, 1914 1,282,864 Knox Oct. 29, 1918 1,391,196 Law Sept. 20, 1921 1,792,947 Watson Feb. 17, 1931 1,836,784 Williams Dec. 15, 1931 1,868,329 Lulofs July 19, 1932 2,100,628 Chandler Nov. 30, 1937 2,233,650 Swartz Mar. 4, 1941 FOREIGN PATENTS 86,360 Australia Nov. 25, 1921

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