US2948909A - Apparatus for cleaning soaking pit burner ports - Google Patents

Description

Aug. 16., 1960 E. w. HAECKLER l 2,948,909

APPARATUS FOR CLEANING soAKING PIT BURNER Poms Filed May 7, 1957 2 Sheets-Sheet 1 Aug. 16., 1960 E. w. HAECKLE'R 2,948,909

APARATUS FOR CLEANING SOAKING PIT BURNER PORTS' Filed May '7, 195'? 2 Sheets-Sheet 2 INVENTOR.

iltiite 1 APPARATUS FOR CLEANING SOAKING PIT Y BURNER PORTS Filed May 7, 19157, Ser. No. 657,575

2 Claims. (CLIS-104.1)

This invention relates toingot soaking pits and, as indicated, to an apparatus for cleaning burner ports in bottom center-fired soaking pits. More particularly, it relates to an apparatus which includes a tool in the nature of a drill and reamer for removing accumulations of slag and cinder from burner ports of the type arranged centrally and extending vertically through Vsoaking pit bottoms. The drilling and reaming tool, in a manner to be described, is adapted for operation in conjunction with and by a conventional ingot crane which thus forms an essential part of the apparatus.

Bottom center-fired soaking pits, sometimes referred to as vertically-tired soaking pits, are so designated by reason of their manner of firing through a refractory burner port located centrally with respect to and extending vertically through a furnace bottom. In burner ports of this character, air for combustion is supplied through an annular space about a fuel pipe extending centrally and axially of the burner port which usually has its upper end spaced axially varying distances from the upper end of the burner port. By reason of its location in the furnace bottom, burner ports of this character are subject to obstruction by accretions of cinder and scale or by slag overflowing from the pit door. During normal operation these materials accumulate on the facing surfaces of the fuelV pipe and the burner port to an extent such that they may bridge the space therebetween, Vand thereby reduce the air required for proper combustion. In addition to ineicient furnace operation from a decreased air supply in this manner, such accretions may divert the burner ilame to one side or the other of the pit thus causing unequal heating of ingots and in some cases burning ofthe burner port refractory. Such conditions of course require cleaning of the burner port to remove the accumulated slag and cinder therefrom.

According to conventional practice, removal of cinder and slag accretions from a burner port is effected in part by operating an ingot crane to lower a spade, a at paddle-like tool of conventional construction commonly used for cleaning out soaking pit bottoms, into the annular space about the burner pipe therein. In addition, such practice generally necessitates the use of crowbars and jackhammers operated by a labor crew working from the bottom side of the air chamber for removal of the remaining slag and cinder accumulations. These operations frequently result in damage to or breakage of States APatent O burner pipes, which are fabricated of relative fragile refractory materials such as pyrofax or Carborundum, with the result that the pit must be taken out of service for burner pipe repair or replacement.

One of the principal objects of this invention is to provide an apparatus which will facilitate and expedite the cleaning of bottom center-tired soaking pit burner ports and which will protect the burner pipe against damage during the cleaning operation. Another and related object is to provide a cleaning tool for this purpose in the form of a trepan and reamer which may be "ice lowered through a burner port with a rotary cutting action to effect removal of slag and cinder accretions from vthe annular space between the facing surfaces of the burner port and its burner pipe. A still further object is to provide an apparatus of this character in which the slag and cinder cutting tool is adapted for operation by the tongs of a conventional ingot crane which thereby forms an essential part of the cleaning apparatus.

- Other objects and advantages of the invention will become apparent from the following description.

In the drawings, there is shown a preferred embodiment of the invention. In this showing:

Figure 1 is an elevational view of a burner port cleaning apparatus constructed in accordance with the principles of this invention;

Figure 2 is a fragmentary view of a portion of the tool shown in Figure 1 looking from a side thereof;

Figures 3 and 4 are respectively topf and bottom plan views of the tool shown in Figure l; and

Figure 5 is a fragmentary vertical sectional view showing the relative position of the cleaning tool of this in.

vention with respect to a soaking pit burner port at the completion of a cleaning operation.

Figure 5 of the drawings shows somewhat diagrammatically a conventional arrangement of a burner port in a bottom center-fired soaking pit. As there shown it comprises the usual pit bottom 1 of coke-breeze on which ingots are supported during a heating operation, a refractory lined burner port 2 arranged centrally and extending vertically through the furnace bottom, and a burner pipe 3 arranged centrally and axially of the port 2 through which gaseous fuel is supplied to the furnace, the air required for combustion being supplied from an underlying air chamber through the annular space 4 between the external surface S of the pipe 3 and the internal surface 6 of the port 2. The refractory lining for the port 2 is provided by the usual bottom brickwork 7 and a monolithic body 8 which is contained in a steel form 9 supported on the brickwork 7. As indicated above, the soaking pit structure thus far described is a conventional arrangement and may be of the type, for example, shown in UnitedStates Patent Nos. 2,297,696 to H. G. Elder et al. and 2,734,734 to F. L. Knight, to which reference may be made for a more detailed showing and description thereof.

During normal operation accretions of slag and cinder form on the surfaces 5 and 6 and interfere with eicient soaking pit operation as explained above. Such accretions derive from molten slag overflowing from the furnace door into the burner port 2 and from hot particles of cinder from the coke-breeze bottom 1 or scale from ingots falling therein and collecting on the surfaces 5- and 6. They collect mainly on the upper end portions of the facing surfaces 5 and 6 and may at times form an obstructing bridge therebetween. An apparatus for effecting their removal is comprised, according to the principles of this invention, of a tool in the nature of a drill or trepan, designated as a whole by the numeral 11, and the tongs 12 of a conventional ingot crane.

The tongs 12 comprise a pair of tong arms 13 which respectively have pivotal connections 14 at their upper ends to a supporting housing 15 depending from and forming part of a conventional ingot crane, and tong bits 16 at their lower ends for biting engagement with an ingot to be handled thereby. The housing 15 is provided with the usual mechanism for pivoting the tong arms 13 toward and away from each other and further has a conventional mounting (not shown) for vertical and rotational movement relative to the ingot crane. The vertical and rotary movement of the housing `15 is effected by conventional drive mechanism on the crane and is essential to proper handling of ingots including their emplacement on a soaking pit bottom. It is utilized, in a manner to be described, as a part of the drilling apparatus of this invention for cleaning the burner port 2.

As best shown in Figures 1 and 2, the tool 11 has a cylindrical shank 20 and a mounting frame 21 secured to the upper end of the shank 20. The frame 21 is constructed for connection with the tongs 12 in such manner that the axis of the tool 11 extends vertically and concentrically with respect to the vertical axis of rotation of the tong housing 15. It comprises a mounting plate 22 having a lower end 23 of reduced size received in the upper end of the shank 20 and rigidly secured thereto by welding along its edges. A pair of filler plates 24 are welded to theY shank 20 and to opposite faces of the mounting plate end 23 to complete the connection of the frame 21 to the shank 20. The upper end of the plate 22 is provided with a recess 2S in which the lower end of the tong housing is received when connected theretoy as shown in Figure 1. Wing plates 26 welded to and projecting `from opposite faces of the mounting plate 22 have outwardly facing openings 27 for the reception of the tong bits 16 as shown in Figure l. The openings 27 are vertically located inV such manner that the tong arms 13 will pivot the bits 16 into an operative position therein as shown in Figure l when the housing 15 is bottomed in the recess 25.

The bit of the tool 11 comprises la trepan in the form of a circular saw 30 which has a welded connection to the lower end of the cylindrical shank 20. It comprises a cylindrical metal ring having radially extending grooves 31 `along its lower edge providing saw teeth 32. Axially extending cutting blades 33 are secured to the tubular shank in positions extending radially outwardly therefrom and above the saw or trepan 30. The mounting of the cutting blades 33 on the shank 20 is provided :in part -by bracing plates 34 of segmental shape which have welded connections at their ends with the blades 33 and along their inner edges with the tubular shank 20. The cutting edges 35 of the blades 33 diverge in an upper direction as viewed in Figure 1 so that they will provide a rearning action with respect to an opening drilled throughV cinder and slag accretions in the annular space 4 by the trepan or drill bit 30. The slope of the cutting edges 35 is of course determined in part by the axial slope of the surface 6 at the upper end of the port 2 as shown in Figure 5.

Assembly of the apparatus for a burner port cleaning operation is effected by lowering the crane tongs 12 to a position in which the tong housing 15 has bottomed e11- gagement in the frame recess 2S. The tong arms 13 are then pivoted to the position shown in Figure 1 with the tong bits 16 securely engaged in the frame openings 27. These operations assemble the apparatus for movement by the ingot `crane to a position over a burner port 2 to be cleaned. When the tool 11 is in a centered position above a burner port 2, the housing 15 is rotated and lowered slowly to move it downwardly into the burner port 2 with a rotary cutting action. As the trepan 30 moves downwardly in the port 2, an annular kerf or opening is cut through accretions adhering to the burner pipe surface 5 and burner port surface 6. Since the lower end 36 of each reamer blade cutting edge 35' (Figure l) has a radial dimension slightly less than the maximum diameter of the opening cut by the trepan 30, continued downward movement of the tool 11 renders the blades 33 effective to enlarge such opening with a reanring action. Figure 5 shows the tool 11 in its lowermost position after it has been operated to clean a burner port 2 of cinder and slag accumulations therein.

Attention is particularly directed to the fact that the cylindrical construction of the shank 20 provides an axially extending space 37 in which the upper end 3S of the burner pipe 3 (see Figure 5) is received during downward cleaning movement ofthe tool 11. In this manner, the upper end 38 of the burner pipe is protected against damage during the cleaning operation. The dimensions of the cylindrical shank 20, trepan 30, and reamer blades 33 are proportioned for maximum removal oi slag and cinder accumulations without damage to the refractory lining of the burner port 2 or to the burner pipe 3. The accretions removed by the tool gravitate into the air chamber at the lower end of the port 2 where they may be easily removed by the port cleaner crew.

While one embodiment of my invention has been shown and described it will be apparent that other adaptations and modifications may be made without departing from the scope of the following claims.

I claim:

1. A tool for operation by the tongs of a conventional ingot crane in the removal of cinder and slag accumulations from the annular space about a burner pipe in the burner port of a bottom center-tired soaking pit comprising, a supporting frame, means at the upper end of said frame for suspending it from said ingot tongs for rotational and vertical movement thereby, a hollow cylinder secured to and depending from said frame with its axis extending vertically and adapted for arrangement in an operating position with such axis aligned with the axis of said port, a trepan secured to the lower end of said cylinder in a concentric position with respect thereto for cutting movement downwardly through said annular space in response to rotary and vertical movement thereof Aby said frame and tongs, and a plurality of circumferentially spaced and axially extending cutting blades secured to and projecting radially outwardly from said cylinder in positions above said trepan, said blades respectively having axially tapered cutting edges along their radially outer surfaces that converge in an axially downward direction from points at their upper ends which are loc-ated radially outwardly with respect to the outer edge of said trepan, to points at their lower ends which are located radially inwardly with respect to the said outer edge of said trepan, said lower end points being spaced axially above said trepan so that vertical downward movement of said frame will cause said blade cutting edges to enter and impart an axially tapered enlargement to a cylindrical opening cutby said trepan.

2. A soaking pit burner port cleaning apparatus as defined in claim 1 characterized by there being a plurality of axially spaced and horizontally extending bracing plates arranged between each adjacent pair of said cutter blades and securing them against movement relative to said cylinder.

References Cited in the le of this patent UNITED STATES PATENTS 1,144,065 Roitzheim et al. June 22, 1915 1,387,414 La Voie Aug. 9, 1921 1,547,651 Hill July 28, 1925 1,937,742 Brink Dec. 5, 1933 2,096,056 Miller Oct. 19, 1937 2,577,605 Clayton Dec. 4, 1951 2,643,203 Drackley June 23, 1953

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