US2967316A - Apparatus for removing burden from a blast furnace - Google Patents

Apparatus for removing burden from a blast furnace Download PDF

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US2967316A
US2967316A US664248A US66424857A US2967316A US 2967316 A US2967316 A US 2967316A US 664248 A US664248 A US 664248A US 66424857 A US66424857 A US 66424857A US 2967316 A US2967316 A US 2967316A
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drill
furnace
burden
frame
members
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Charles W Kandle
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    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F27FURNACES; KILNS; OVENS; RETORTS
    • F27DDETAILS OR ACCESSORIES OF FURNACES, KILNS, OVENS, OR RETORTS, IN SO FAR AS THEY ARE OF KINDS OCCURRING IN MORE THAN ONE KIND OF FURNACE
    • F27D25/00Devices or methods for removing incrustations, e.g. slag, metal deposits, dust; Devices or methods for preventing the adherence of slag
    • F27D25/001Devices or methods for removing incrustations, e.g. slag, metal deposits, dust; Devices or methods for preventing the adherence of slag comprising breaking tools, e.g. hammers, drills, scrapers

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  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Blast Furnaces (AREA)

Description

Jan. 10, 1961 C, w, KANDLE 2,967,316
APPARATUS FOR REMOVING BURDEN FROM A BLAST FURNACE Filed June 7. 1957 2 Sheets-Sheet 1 INVENTOR.
Charles Wlcmd le ATTORNEYS.
Jan. 10, 1961 c. w. KANDLE APPARATUS FOR REMOVING BURDEN FROM A BLAST FURNACE Filed June 7. 1957 2 Sheets-Sheet 2 INVENTOR. Charles WKcmdZe AT TORN E YS.
nited States Patent() APPARATUS FOR REMOVING BURDEN FROM A BLAST FURNACE Charles W. Kandle, 1420 Robinhood Lane, La Grange Park, Ill.
Filed June 7, 1957, Ser. No. 664,248
1 Claim. (Cl. 15-104.1)
This invention relates to an apparatus for removing burden from a blast furnace.
Periodically it becomes necessary to remove the burden from a blast furnace. Because frequently more than one thousand tons of burden are involved, it takes a number of men days to effect removal. It is hazardous work since some workmen must climb inside where loosened burden may slide or lining bricks ymay fall from considerable heights. And since temperatures within the furnace range above 3200 F., it takes days to cool down such a furnace before workmen may enter to effect removal. Generally, the removal of burden requires up to two weeks of expensive down-time before the furnace can be placed in operation again.
According to the present invention, the burden of a blast furnace is removed by a single drill unit or by a plurality of circumferentially spaced drilling units which are adapted to cut and remove the burden from the furnace. The drill carried by the unit enters the furnace through the tuyeres and the vibrations emanating from the unit causes the burden to move downwardly within the furnace to the removal zone.
The apparatus by which removal of burden from a blast furnace is effected in accordance with this invention, includes a frame which is adjustable with respect to the tuyere level of the furnace and is provided with means for securement to the outer wall of the furnace. The frame includes ways upon which a carriage is adapted to slide. Means are provided for reciprocating the carriage upon the frame in a radial direction With respect to the furnace. Upon the carriage is mounted a drill having a cutting head and ights to remove the loosened material and drive means for the drills. Stabilizing and centralizing means for the drill are carried forwardly on the frame. The frame further includes conveyor means for receiving the loosened burden from the drill flights for delivery to a vehicle or an out-of-way location.
The drawings furnished herewith illustrate the best mode of carrying out the invention as presently contemplated and set forth hereinafter.
In the drawings:
Figure 1 is a side elevation with portions broken away v showing the drilling apparatus of this invention;
Fig. 2 is a sectional view taken generally on line 2-2 of Figure 1; and
Fig. 3 is a sectional view through a blast furnace showing a plurality of drilling apparatus disposed circum- V ferentially around the furnace to remove the burden therefrom.
Referring to the drawings, the drilling apparatus is Y provided with a frame 1 comprising a pair of transversely ICC 7. Longitudinal bracing members 8 connect members 6 adjacent the upper ends thereof. Each tubular member 5 is provided with a plurality of vertically spaced diametrically aligned openings 9 which are adapted to be aligned with diametral openings 10 provided in the upper end of each tubular member 6. After the frame 1 is adjusted tov a predetermined height, a pin 11 is disposed in aligned openings 9 and 10 to secure the frame with respect to the skids.
The upper surface 12 of the structural frame members 2 and 3 provide a slide upon which the drill carriage 13 is actuated longitudinally of the frame. A pair of rollers 13a are mounted on brackets 13b which are secured on opposite side of the lower surface of carriage 13. These rollers are adapted to bear against the lower side of the upper flanges of frame members 2 and 3 and serve to securely hold the carriage on the latter. The drive for carriage 13 includes a pair of transversely spaced flexible members in the form of continuous roller chains 14 to which the carriage is secured by the bolts 14a extending through the chains and carriage 13. Each exible member 14 extends over a rotary member such as an idler sprocket 15 mounted on shaft 16 carried between frame members 2 and 3 at the forward end of the drilling apparatus and over the rotary drive member or sprocket 17 mounted on shaft 18 between the frame members at the rearward end of the apparatus. The flexible members 14 are driven by a motor 19 through the chain drive 20 connecting shaft 18 and the motor drive. A suitable transmission, not shown, is provided between motor 19 and the chain drive 20 so that the carriage 13 may be reciprocated with respect' to the frame 1.
Carriage drive members 14 are further provided with tensioning means whereby the chains may be maintained taut. The shaft 16 carrying idler sprockets 15 extends through longitudinal slots 22 provided in structural members 2 and 3 and are journaled in movable bearing members 23 which are guided between the flanges of the structural members. Each bearing member 23 is provided with a longitudinal extending threaded member 24 which extends through an opening in a transverse projection 25 extending outwardly from members 2 and 3. Each bearing 23 is secured with respect to the frame by a pair of nuts 26 and 27 threaded on member 24 on opposite sides of projection 25. To tension chains 14, nut 27 is loosened from its position abutting on projection 25 and the nut 26 is rotated to move the bearing 23 and shaft 16 forwardly within the slot 22. After the desired tensioning has been accomplished, the nut 27 is again threaded against projection 25 to lock the bearing 23 with respect to the frame.
The drill carriage 13 carries the drill unit 28 including a pair of air motors 29 and 30 for operating the drill 31. The drill 31 includes the shaft 32 journaled in bearing 33, and rotated by the chain drives 34 and 35 connecting the shaft 32 and the respective motors 29 and 30. Forwardly of bearing 33 the drill shaft 32 is provided with a water survel 36 provided with suitable water connections, not shown, for circulating cooling water through the shaft 32 to kcool -the auger or drill ghts 37 and drill head 38 carried by the shaft 32.
To further supportand centralize the drill 31, a directional sleeve in the form of a semi-cylindrical member 39 opening upwardly and having a radius corresponding substantially to that of the drill is mounted at the forward end of frame 1 to receive the lower portion of the drill.
With the construction above described there has been provided an integral and compact drill unit and drive means therefor. The arrangement is free of complex drive mechanisms yet it provides for various speeds of the drill. A single slide supports the drill and power source therefor for reciprocation on the rigid frame. In operation the drill and auger bounce whip around to a certain extent as they are forcibly driven in the material. This movement causes considerable vibration in the burden to cause loosening thereof. The flexible drive for the slide is contained between the frame members where it utilizes otherwise unused space and yet provides for maximum travel of the carriage.
Conveyor means 40 are provided beneath the structural members 2 and 3 and between the transversely spaced tubular members 6 of the frame. The endiess belt-type conveyor means extends beyond the longitudinal extremities of frame members 2 and 3 and comprises transversely spaced side walls 41 which are ad. justably supported from the frame by means of the threaded members 42, as will be explained hereinafter. The spaced side walls 41 are provided with transversely aligned bearings 43 adjacent the forward end of the walls for journally receiving the transverse shaft 44 carrying spaced idler sprockets 45. Adjacent the rearward end, the side walls 41 of conveyor 40 are provided with transversely aligned slots 46 for receiving the shaft 47 carry ing drive sprockets 48 in longitudinal alignment with idler sprockets 45. The shaft 47 extends through the aligned slots 46 and is journally received by adjustable bearing members 49. Roller chains 50 are disposed around sprockets 45 and 48 and carry a plurality of closely spaced transverse metal slats 51 adapted to receive the loose burden as delivered by the drill ights. With this structure, the entire conveyor, although of the exible endless belt type, is of fireproof construction. Shaft 47 carrying drive sprockets 4S is driven by the air motor 52 which is secured relative to bearing 49. The conveyor 40 is further provided with longitudinal guide means 53 comprising longitudinal plates extending up- Wardly and angular from the path of slats 51 and supported by side walls 41 for directing the loose burden onto the central portion of slats 51.
The conveyor chains may be tensioned in a manner Vsimilar' to the carriage drive chains 14 with threaded members 54 being connected to the bearing members 49 and extending through openings in the transverse projections 55 provided on the side walls 41. Nuts 56 and 57 are provided on opposite sides of projection 55 and may be manipulated similarly to nuts 26 andl 27 to take up slack in chains 50 by moving the bearings 49 together with the motor 52 relative to the aligned slots 46. A
The conveyor means 4t) are adjustably suspended from the frame by means of longitudinally spaced pairs of threaded members 42. The individual members 42 of each pair are spaced to each side of the conveyor means 40 and are pivotally secured to projections 58 provided on bracing members 8. A pair of transversely aligned bearings 59 are secured to the underside of the conveyor means 40 substantially in vertical alignment with the projections 58 and a transversely extending supporting shaft 60 is rotatably disposed therein and extends outwardly beyond side walls 41 of the conveyor means. The ends of shaft 60 are provided with at portions 61 having a hole therein for loosely receiving the threaded members 42. The shaft 60 may be positioned, as desired, with respect to the length of each pair of members 42 and secured in place by nuts 62 and 63 disposed respectively to each side of end portions 61. As shown in Figure l', the supporting shafts 60 are secured with respect to the longitudinally spaced pairs of threaded members 42 to provide a rearwardly'upward slope for the conveyor means 40.
To secure the drilling apparatus against the thrusty imposed by the drill 31, a pair of extensible tie rods 64 connect the frame 1 to the metal sheathing 65 surrounding the frebrick Wall 66 of the blast furnace. The tie rods 64 are pivotally connected to the foremost skids of the frame 7 at 67, which is substantially below the level of drill 31, and extend upwardly at an angle to engage the metal sheathing 6 5 above the tuyere level of the furnace and substantially above `the level of drill 31 where the rods are pivotally connected at 68. The rods 64 are made extensible, as shown in Figure l, so that the distance between the surface on which the drilling apparatus rests and the furnace wall connection may vary. An extensible chute 69 is pivotally mounted between side walls` 41 of conveyor 40 and extends upwardly and forwardly between the tie rods 64 to engage the wall of the furnace beneath the drill 31 and is adapted to receive the loose burden carried out of the furnace by the drill ights 37.
In preparation for removing the burden from a blast furnace, the drilling apparatus of this invention is placed adjacent to the furnace and the tie-rods 64 are secured to the metal sheathing of the furnace wall. Prior to such placement or thereafter the frame height is adjusted so that the drill 31 will enter the furnace at the tuyere level through the tuyere openings 76 in the metal sheathing 65. The chute 69 is adjusted in position to receive the loose burden delivered by the helical drill flights 37 and the conveyor means 40 are positioned to deliver the burden at the height desired to a waiting vehicle, not shown, or the like. The burden, as it leaves the furnace, is often red hot, and the conveyor 40 travels about 250 feet per minute to quickly convey it away. There is no danger from gas to the operator on the frame 1 as there would otherwise be within the furnace.
After the drilling apparatus has been positioned for operation and the various elements thereof properly adjusted, the drill 31 is actuated by the motors 29 and 30. The drill carriage 13 is then advanced by the drive chain 20 driven by air motor 19 to pass the drill head through the tuyere opening 70 of the metal sheathing 65 encasing the brick wall 66 of the furnace. Within the tuyere a skinf 66a has formed during operation of the furnace, through which the drill must rst penetrate. This skinl may comprise slagy and cope of varying proportions and is of considerable hardness. After drilling through this skin and removing it, the drill is forcibly inserted into the burden within the furnace, being rotatably driven all the time to bore its way in. Upon reaching the interior of the furnace, longitudinal movement of the drill is stopped or the drill may be adjustably positioned at various degrees of penetration into the furnace as the cleaning process is carried out.
Byl means of this particular support structure, the drill and its integral power source may be vertically adjust able relative to the oor to accommodate tuyere openings of various heights. The conveyor may also be adjusted in a vertical direction, not only relative to the floor but also to the drill, so that the adjustable chute can be placed in proximity to the material being discharged from the tuyere opening. The ends of the conveyor are also adjustable in a vertical direction relative to one another.
In the course of operation of the drilling apparatus, a considerable vibration is set up in the mass of burden contained in the furnace above the drill 31. This vibration serves to loosen the burden from the wall of the furnace and causes the burden to move downwardly within the furnace to the drill 31 for removal to the outside. Varying and intermittent back thrust of drill 31 tends to vibrate frame 1 vertically and cause whipping of the drill, in view of the positioning of tie rods 64.
For removal of burden from a blast furnace, it is gen erally more desirable to employ a number of the drilling apparatus of this invention. As shown in Fig. 3, the
dr-ills 31 of the drilling apparatus are disposed to enter the furnace in circumferentially spaced relation. Employed in this manner, the vibrations set up by each apparatus tend to complement each other to provide a more effective means for loosening the mass of burden in the furnace and causing the same to move downwardly toward the drill ights for removal.
Not only has the apparatus of this invention relieved the large crew of workmen ordinarily needed for removing burden from a blast furnace, but removal is accomplished in a fraction of the time it took such a crew. Furthermore, the apparatus has a great safety factor to the men as well. Down-time to permit cooling of the furnace from temperatures normally employed is also -greatly reduced since the apparatus of this invention can enter the furnace long before workmen can enter the furnace to effect removal of the burden. This reduction in cooling time and the reduction of removal time effected by the apparatus of this invention has greatly reduced the down-time before the blast furnace can be placed in operation once again.
Various modes of carrying out the invention are contemplated as being within the scope of the following claim particularly pointing out and distinctly claiming the subject matter which is regarded as the invention.
I claim:
In apparatus of the class described for loosening and removing burden from blast furnaces and the like, a frame adapted to be operationally disposed in front of a furnace tuyere, a carriage mounted on said frame for reciprocation toward and away from the furnace, a rotary drill unit on said carriage and adpted to enter through the tuyere into the burden in the furnace as said carriage moves toward the furnace, said drill unit including conveying means for removing loosened burden out through the tuyere, and a tie secured to the end of the frame near the furnace by a pivot having a horizontal transverse axis disposed substantially below the level of said drill, said tie operationally extending upwardly at an angle toward the furnace and being adapted to be secured to the furnace by a pivot having a horizontal transverse axis disposed substantially above the level of said drill, whereby varying and intermittent back thrust of the drill tends to vibrate the frame vertically and cause whipping of the drill.
References Cited in the tile of this patent UNITED STATES PATENTS 529,996 Baker Nov. 27, 1894 747,868 Drake Dec. 22, 1903 1,014,258 Ross Jan. 9, 1912 1,100,476 Gill June 16, 1914 1,557,953 Witkowski Oct. 20, 1925 1,580,001 Bicknell Apr. 6, 1926 1,639,731 Humiston Aug. 23, 1927 1,676,389 Fletcher July 10, 1928 1,827,085 Hui Oct. 13, 1931 1,872,016 Sherwood et al. Aug. 16, 1932 1,916,261 Giese July 4, 1933 1,932,068 Englebright et al. Oct. 24, 1933 2,205,757 Wheat June 25, 1940 2,550,684 Fouguet May 1, 1951 2,659,916 Lewis Nov. 24, 1953 2,764,397 Compton Sept. 25, 1956
US664248A 1957-06-07 1957-06-07 Apparatus for removing burden from a blast furnace Expired - Lifetime US2967316A (en)

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Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3090983A (en) * 1961-02-06 1963-05-28 Modrak Frank Carrier and manipulator for pneumatic tools
US3400419A (en) * 1966-03-21 1968-09-10 Joseph C. Fuller Tube-cleaning device
US3990836A (en) * 1975-05-05 1976-11-09 Bricmont & Associates, Inc. Hearth cleaning apparatus
US4087083A (en) * 1975-06-10 1978-05-02 A. Daidoseiko K.K. Manipulator
US5474097A (en) * 1993-11-10 1995-12-12 Atlantic Richfield Company Scale removal and disposal system and method
US6499173B2 (en) * 2000-12-07 2002-12-31 Leslie Van Ornum Culvert cleaning apparatus
US9597717B1 (en) 2012-02-27 2017-03-21 Daniel Wayne Snow Pipe cleaning apparatus

Citations (16)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US529996A (en) * 1894-11-27 Drill
US747868A (en) * 1903-04-17 1903-12-22 Chester T Drake Excavating-machine.
US1014258A (en) * 1911-03-13 1912-01-09 Northern Iron Company Kiln-cleaner.
US1100476A (en) * 1913-02-24 1914-06-16 Geoffrey Murton Gill Clinker-breaking machine.
US1557953A (en) * 1925-03-17 1925-10-20 Walter B Witkowski Tapping machine for stationary open-hearth furnaces
US1580001A (en) * 1925-07-28 1926-04-06 Bicknell Robert Henry Excavating apparatus
US1639731A (en) * 1927-08-23 Means fob installing geotjnd pipes
US1676389A (en) * 1925-11-09 1928-07-10 Fletcher Harold Wheelock Method of cleaning soaking drums
US1827085A (en) * 1923-08-30 1931-10-13 Universal Oil Prod Co Method for cleaning stills
US1872016A (en) * 1930-07-28 1932-08-16 Allendale Mfg Company Inc Surface mining
US1916261A (en) * 1933-07-04 giese
US1932068A (en) * 1930-07-22 1933-10-24 Hydrauger Corp Ltd Earth boring apparatus
US2205757A (en) * 1937-09-18 1940-06-25 Standard Oil Dev Co Coke cleaning apparatus
US2550684A (en) * 1948-03-01 1951-05-01 Fouquet Robert Apparatus for production of volatilizable metals
US2659916A (en) * 1948-10-07 1953-11-24 C A Lewis Inc Coke remover for tar and petroleum stills and the like
US2764397A (en) * 1956-06-01 1956-09-25 Charles E Compton Auger mining apparatus having rigidly attached transverse conveyor

Patent Citations (16)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US529996A (en) * 1894-11-27 Drill
US1916261A (en) * 1933-07-04 giese
US1639731A (en) * 1927-08-23 Means fob installing geotjnd pipes
US747868A (en) * 1903-04-17 1903-12-22 Chester T Drake Excavating-machine.
US1014258A (en) * 1911-03-13 1912-01-09 Northern Iron Company Kiln-cleaner.
US1100476A (en) * 1913-02-24 1914-06-16 Geoffrey Murton Gill Clinker-breaking machine.
US1827085A (en) * 1923-08-30 1931-10-13 Universal Oil Prod Co Method for cleaning stills
US1557953A (en) * 1925-03-17 1925-10-20 Walter B Witkowski Tapping machine for stationary open-hearth furnaces
US1580001A (en) * 1925-07-28 1926-04-06 Bicknell Robert Henry Excavating apparatus
US1676389A (en) * 1925-11-09 1928-07-10 Fletcher Harold Wheelock Method of cleaning soaking drums
US1932068A (en) * 1930-07-22 1933-10-24 Hydrauger Corp Ltd Earth boring apparatus
US1872016A (en) * 1930-07-28 1932-08-16 Allendale Mfg Company Inc Surface mining
US2205757A (en) * 1937-09-18 1940-06-25 Standard Oil Dev Co Coke cleaning apparatus
US2550684A (en) * 1948-03-01 1951-05-01 Fouquet Robert Apparatus for production of volatilizable metals
US2659916A (en) * 1948-10-07 1953-11-24 C A Lewis Inc Coke remover for tar and petroleum stills and the like
US2764397A (en) * 1956-06-01 1956-09-25 Charles E Compton Auger mining apparatus having rigidly attached transverse conveyor

Cited By (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3090983A (en) * 1961-02-06 1963-05-28 Modrak Frank Carrier and manipulator for pneumatic tools
US3400419A (en) * 1966-03-21 1968-09-10 Joseph C. Fuller Tube-cleaning device
US3990836A (en) * 1975-05-05 1976-11-09 Bricmont & Associates, Inc. Hearth cleaning apparatus
US4087083A (en) * 1975-06-10 1978-05-02 A. Daidoseiko K.K. Manipulator
US5474097A (en) * 1993-11-10 1995-12-12 Atlantic Richfield Company Scale removal and disposal system and method
US6499173B2 (en) * 2000-12-07 2002-12-31 Leslie Van Ornum Culvert cleaning apparatus
US9597717B1 (en) 2012-02-27 2017-03-21 Daniel Wayne Snow Pipe cleaning apparatus
US9770741B1 (en) 2012-02-27 2017-09-26 Daniel Wayne Snow Pipe cleaning apparatus
US9862010B2 (en) 2012-02-27 2018-01-09 Daniel Wayne Snow Pipe cleaning apparatus

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