US3182734A - Fusion piercing or drilling machine - Google Patents

Fusion piercing or drilling machine Download PDF

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US3182734A
US3182734A US250810A US25081063A US3182734A US 3182734 A US3182734 A US 3182734A US 250810 A US250810 A US 250810A US 25081063 A US25081063 A US 25081063A US 3182734 A US3182734 A US 3182734A
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combustion head
coolant
reamers
conduit means
lugs
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US250810A
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Russell W Scott
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    • E—FIXED CONSTRUCTIONS
    • E21—EARTH OR ROCK DRILLING; MINING
    • E21B—EARTH OR ROCK DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS
    • E21B7/00—Special methods or apparatus for drilling
    • E21B7/14—Drilling by use of heat, e.g. flame drilling

Definitions

  • Fusion piercing machines employ a set of rota-ting reamers and high-temperature, high-velocity llames to break down .and penetrate ores that are economically unworkable with conventional drilling equipment.
  • this type of equipment consists of a long, rotatably mounted kelly, Ior pipe, at one end of which is mounted a combustion head adapted to produce generally axially extending high-velocity flames at its bottom face.
  • the combustion head is enclosed in a cylindrical reamer shell which has a plurality of hard surfaced reamer lugs secured to its periphery and extending slightly further than the shell and the combustion head.
  • the drilling head is cooled by cooling water which is passed through the kelly and around the combustion chamber and is permit-ted to escape axially through a plurality of ports in the bottom face of the combustion head.
  • cooling water As the cooling water leaves the combustion head, it encounters the extremely high operating temperatures and almost instantaneously bursts into high pressure steam which blows the cut m-aterial from underneath the blow pipe and up through the hole produced thereby.
  • the reamer lugs Although being hard surtaced, wearV down to an unusable size Within approximately thirty .feet of drilling (in Taeonite ores), where the drill has to be withdrawn and replaced.
  • the worn Ihead may be salvaged by removal and replacement ofthe worn lugs but the shell must also be replaced about every third time the lugs 4are replaced. This necessary periodic stoppage of the equipment ifo-r repair or replacement constitutes a very significant maintenance and down time expense.
  • the principal object of this invention is to increase the eiciency of the fusion piercing drilling machines by pro- Viding better and longer lasting reamer lugs.
  • This object is attained by passing a portion of the cooling water through substantially the entire length of each reamer lug and discharging i-t through upwardly angled ports located on the trailing side of the lug.
  • This type of water cooling substantially reduces the operating temperature of the reamer lugs and drills embodying this invention are able to drill about twice as far as those used heretofore, rand even after such operation only the leading corner of each lug has to be resurfaced as compared to the replacement of the entire lug as required With known equipment.
  • the high pressure steam produced at the side of each lug helps move the cut material upwardly.
  • Another advantage of this invention is that due to the decreased and more confined wear of the reamer lugs, the entire blow pipe is considerably bet-ter guided in the drilled hole, with resulting reduced wear of the reamer shell, the kelly and its bearing support structure. Generally, the new lugs can be reworked live times (compared to three) before the shell needs replacement.
  • FIG. 1 represents the fragmentary side View of the fusion piercing machine and a schematic view of its driving means
  • FIG. 2 represents a cross-:sectional fragmentary view of the fusion piercing machine .and a cross-sectional View of the combustion chamber;
  • FIG. 3 represents a bottom View of the fusion piercing machine; and l FIG. 4 represents a cross-sectional view of the reamer
  • FIG. 1 shows the fusion piercing machine assembly which is rotatably mounted in suitable support structure 10.
  • Oil and oxygen are conveyed through kelly 12 by conduits 14 and 16 respectively to combustion head 18 where they are mixed in cham-ber 20 t-o produce high-temperature and high-velocity flames at orifices 22, 22 in the bottom face of the combustion head.
  • the dutiess are so spaced as to produce fairly uniform coverage and heating of the area below the drill head when it is rotated during operation.
  • Reamer shell 24, having reamer lugs 26, 26 uniformly spaced on its outer periphery is removably attached to the kelly and encloses the combustion he-ad.
  • the lugs have their longitudinal face portion 28 parallel to the axis of theV kelly and have their tips 30 extending slightly past the bottom face of combusti-on head 18 and reamer shell 24 to space the head from the bott-om of the hole. Since ⁇ the severest heat and wear is experienced by the lug tips, they are somewhat thicker than the main 'body of the lug, and are bevelled longitudinally and transversely to form an angular cutting surface 32 and a heavy leading tip corner 34.
  • Cooling water is pressure fed to the combustion head by means of passage 36 in the kelly. A portion of the cooling water flows through passages 38 next to the combustion chamber to escape through ports 40, 40 for conversion to high pressure steam. Another portion of the cooling water flows through inlet ports 42, 42 into longitudinal cavities 44, 44 within lugs 26, from which it escapes through upwardly angled ports 46 on trailing side 48 of the lugs. The ports are located above the lower extremity 49 of cavity 44 to provide for discharge above the debris to reduce likelihood of fouling the ports.
  • the cooling of the lugs proves quite signicant. With the old construction the hard surfaced lugs showed evidence of having reached the plastic state where material was actually wiped off. With the cooling of the lugs the wear is conned to the tips of the lugs with no evidence of having reached the plastic state.
  • Lugs 26 are welded to the reamer shell and are hard surfaced with a layer 50 of suitable hard surfacing material (an alloy of cobalt, chromium and tungsten), as Stellite 6.
  • the drilling head may easily be reconditioned merely by rebuilding such corners with the hard surfacing material which may be applied to the lugs by arc Welding. While the lugs are repaired easily (compared with replacement in the past) it is also important to note the lugs can be reworked five times before the shell needs replacement (three times with the old construction). This indicates the improved guiding afforded by the present rig. On top of all this the drill will pierce about twice as much rock before requiring resurfacing. All told, it appears maintenance costs are reduced by about twenty percent and this is significant since these rigs now run many thousands of dollars per month for maintenance.
  • Fusion piercing apparatus comprising:
  • a combustion head secured to said kelly and having a mixing chamber and axially outwardly facing' orifices in communication with said lirst conduit means, and coolant passages in communication with said second conduit means and surrounding said mixing chamber, said coolant passages being in communication with axially extending ports for conveying a part of the liquid coolant to the atmosphere;
  • each of said reamers having an inlet port in communication with at least one of said coolant passages of said combustion head and having an outlet port to the atmosphere to thereby convey a part of the liquid coolant directly to the atmosphere through the reamer.
  • Apparatus according lto kclaim 1 wherein said kelly is adapted to operably rotate in one direction, and said exit ports are located in the trailing side of said reamers and are angled away from the flames to discharge the coolant in an upward direction during operation of the fusion piercing apparatus.

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  • Life Sciences & Earth Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Geology (AREA)
  • Mining & Mineral Resources (AREA)
  • Physics & Mathematics (AREA)
  • Environmental & Geological Engineering (AREA)
  • Fluid Mechanics (AREA)
  • General Life Sciences & Earth Sciences (AREA)
  • Geochemistry & Mineralogy (AREA)
  • Earth Drilling (AREA)

Description

May 11, 1965 R. w. SCOTT FUSION PIERCING OR DRILLING MACHINE Filed Jan. 1l, 1963 om gv v 3 QN il i IV MMM .mx W N @a W, l 0. MM W 7/ /rf//Ai4 d M Toi ATTORNEY i I. -Q1. .J
United States Patent 3,182,734 FUSION PIERCING 0R DRILLING MACHINE Russell W. Scott, 1000 Detroit Ave., Iron Mountain, Mich. Filed Jan. 11, 1963, Ser. No. 250,810 Claims. (Cl. 17S-14) This invention relates to fusion piercing (drilling) machines which are employed to penetrate extremely hard ores. Y
Fusion piercing machines employ a set of rota-ting reamers and high-temperature, high-velocity llames to break down .and penetrate ores that are economically unworkable with conventional drilling equipment. Basically, this type of equipment consists of a long, rotatably mounted kelly, Ior pipe, at one end of which is mounted a combustion head adapted to produce generally axially extending high-velocity flames at its bottom face. The combustion head is enclosed in a cylindrical reamer shell which has a plurality of hard surfaced reamer lugs secured to its periphery and extending slightly further than the shell and the combustion head.
The drilling head is cooled by cooling water which is passed through the kelly and around the combustion chamber and is permit-ted to escape axially through a plurality of ports in the bottom face of the combustion head. As the cooling water leaves the combustion head, it encounters the extremely high operating temperatures and almost instantaneously bursts into high pressure steam which blows the cut m-aterial from underneath the blow pipe and up through the hole produced thereby.
Due to the extremely high operating temperatures of this equipment, the reamer lugs, although being hard surtaced, wearV down to an unusable size Within approximately thirty .feet of drilling (in Taeonite ores), where the drill has to be withdrawn and replaced. The worn Ihead may be salvaged by removal and replacement ofthe worn lugs but the shell must also be replaced about every third time the lugs 4are replaced. This necessary periodic stoppage of the equipment ifo-r repair or replacement constitutes a very significant maintenance and down time expense.
The principal object of this invention is to increase the eiciency of the fusion piercing drilling machines by pro- Viding better and longer lasting reamer lugs.
This object is attained by passing a portion of the cooling water through substantially the entire length of each reamer lug and discharging i-t through upwardly angled ports located on the trailing side of the lug.
This type of water cooling substantially reduces the operating temperature of the reamer lugs and drills embodying this invention are able to drill about twice as far as those used heretofore, rand even after such operation only the leading corner of each lug has to be resurfaced as compared to the replacement of the entire lug as required With known equipment. The high pressure steam produced at the side of each lug helps move the cut material upwardly.
Another advantage of this invention is that due to the decreased and more confined wear of the reamer lugs, the entire blow pipe is considerably bet-ter guided in the drilled hole, with resulting reduced wear of the reamer shell, the kelly and its bearing support structure. Generally, the new lugs can be reworked live times (compared to three) before the shell needs replacement.
Other objects and advantages will be pointed out in,
or be apparent from, the specification and claims, as will obvious modifications of the single embodiment shown in the drawings in which:
FIG. 1 represents the fragmentary side View of the fusion piercing machine and a schematic view of its driving means;
ICC
FIG. 2 represents a cross-:sectional fragmentary view of the fusion piercing machine .and a cross-sectional View of the combustion chamber;
FIG. 3 represents a bottom View of the fusion piercing machine; and l FIG. 4 represents a cross-sectional view of the reamer Referring to the drawings in detail, FIG. 1 shows the fusion piercing machine assembly which is rotatably mounted in suitable support structure 10.
Oil and oxygen are conveyed through kelly 12 by conduits 14 and 16 respectively to combustion head 18 where they are mixed in cham-ber 20 t-o produce high-temperature and high-velocity flames at orifices 22, 22 in the bottom face of the combustion head. The orices are so spaced as to produce fairly uniform coverage and heating of the area below the drill head when it is rotated during operation. Reamer shell 24, having reamer lugs 26, 26 uniformly spaced on its outer periphery is removably attached to the kelly and encloses the combustion he-ad. The lugs have their longitudinal face portion 28 parallel to the axis of theV kelly and have their tips 30 extending slightly past the bottom face of combusti-on head 18 and reamer shell 24 to space the head from the bott-om of the hole. Since `the severest heat and wear is experienced by the lug tips, they are somewhat thicker than the main 'body of the lug, and are bevelled longitudinally and transversely to form an angular cutting surface 32 and a heavy leading tip corner 34.
Cooling water is pressure fed to the combustion head by means of passage 36 in the kelly. A portion of the cooling water flows through passages 38 next to the combustion chamber to escape through ports 40, 40 for conversion to high pressure steam. Another portion of the cooling water flows through inlet ports 42, 42 into longitudinal cavities 44, 44 within lugs 26, from which it escapes through upwardly angled ports 46 on trailing side 48 of the lugs. The ports are located above the lower extremity 49 of cavity 44 to provide for discharge above the debris to reduce likelihood of fouling the ports. The cooling of the lugs proves quite signicant. With the old construction the hard surfaced lugs showed evidence of having reached the plastic state where material was actually wiped off. With the cooling of the lugs the wear is conned to the tips of the lugs with no evidence of having reached the plastic state.
Lugs 26 are welded to the reamer shell and are hard surfaced with a layer 50 of suitable hard surfacing material (an alloy of cobalt, chromium and tungsten), as Stellite 6. The drilling head may easily be reconditioned merely by rebuilding such corners with the hard surfacing material which may be applied to the lugs by arc Welding. While the lugs are repaired easily (compared with replacement in the past) it is also important to note the lugs can be reworked five times before the shell needs replacement (three times with the old construction). This indicates the improved guiding afforded by the present rig. On top of all this the drill will pierce about twice as much rock before requiring resurfacing. All told, it appears maintenance costs are reduced by about twenty percent and this is significant since these rigs now run many thousands of dollars per month for maintenance.
Although only a single embodiment of the present invention has been illustrated and described, it will be apparent to those skilled in the art that various changes and modifications may be made therein without departing from the spirit of the invention or from the scope of the appended claims.
I claim:
1. Fusion piercing apparatus comprising:
a kelly rotatably mounted in a support structure and containing tirst conduit means for conveying com- 3 bustible material and second conduit means for conveying a liquid coolant;
a combustion head secured to said kelly and having a mixing chamber and axially outwardly facing' orifices in communication with said lirst conduit means, and coolant passages in communication with said second conduit means and surrounding said mixing chamber, said coolant passages being in communication with axially extending ports for conveying a part of the liquid coolant to the atmosphere;
a plurality of reamers surrounding said combustion head, said combustion head being adapted to produce high temperature flames at said orifices which ames in combination with said reamers are adapted to penetrate hard ores; and
a coolant passage provided within each of said reamers having an inlet port in communication with at least one of said coolant passages of said combustion head and having an outlet port to the atmosphere to thereby convey a part of the liquid coolant directly to the atmosphere through the reamer.
2. Apparatus according lto kclaim 1 wherein said kelly is adapted to operably rotate in one direction, and said exit ports are located in the trailing side of said reamers and are angled away from the flames to discharge the coolant in an upward direction during operation of the fusion piercing apparatus.
3. Apparatus according to claim 2 wherein said reamers extend longitudinally with respect to said kelly and have tips extending beyond said combustion head, each of said tips being heavier on its leading side than on its trailing side.
4. Apparatus according to claim 2 wherein said reamers extend longitudinally withV respect Vto said kelly, each coolant passage extending through substantially the entire length of the reamer, and each exit port being positioned between the longitudinal extremities of said coolant passage.
5. An aperture according to claim 1 wherein said outlet ports of the reamers are located on one side of each reamer.
References Cited by the Examiner Y UNITED STATES PATENTS 2,327,499 8/43 Burch 175-15 2,327,508 8/43 Craig 175-15 2,675,994 4/54 Smith et al." n 175-15 XR 3,093,197 6/63 Freeman etal l75-14 CHARLES E. OCONNELL, Primary Examiner.

Claims (1)

14. FUSING PIERCING APPARATUS COMPRISING: A KELLEY ROTATABLY MOUNTED IN A SUPPORT STRUCTURE AND CONTAINING FIRST CONDUIT MEANS FOR CONVEYING COMBUSTIBLE MATERIAL AND SECOND CONDUIT MEANS FOR CONVEYING A LIQUID COOLANT; A COMBUSTION HEAD SECURED TO SAID KELLY AND HAVING A MIXING CHAMBER AND AXIALLY OUTWARDLY FACING ORIFICES IN COMMUNICATION WITH SAID FIRST CONDUIT MEANS, AND COOLANT PASSAGES IN COMMUNICATION WITH SAID SECOND CONDUIT MEANS AND SURROUNDING SAID MIXING CHAMBER, SAID COOLANT PASSAGES BEING IN COMMUNICATION WITH AXIALLY EXTENDING PORTS FOR CONVEYING A PART OF THE LIQUID COOLANT TO THE ATMOSPHERE; A PLURALITY OF REAMERS SURROUNDING SAID COMBUSTION HEAD, SAID COMBUSTION HEAD BEING ADAPTED TO PRODUCE HIGH TEMPERATURE FLAMES AT SAID ORIFICES WHICH FLAMES IN COMBINATION WITH SAID REAMERS ARE ADAPTED TO PENETRATE HARD ORES; AND A COOLANT PASSAGE PROVIDED WITHIN EACH OF SAID REAMERS HAVING AN INLET PORT INCOMMUNICATION WITH AT LEAST ONE OF SAID COOLANT PASSAGES OF SAID COMBUSTION HEAD AND HAVING AN OUTLET PORT TO THE ATMOSPHERE TO THEREBY CONVEY A PART OF THE LIQUID COOLANT DIRECTLY TO THE ATMOSPHERE THROUGH THE REAMER.
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Cited By (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3322213A (en) * 1964-03-31 1967-05-30 Union Carbide Corp Thermal mechanical mineral piercing
US3344870A (en) * 1965-03-19 1967-10-03 Hughes Tool Co Reamer for jet piercer
US4073351A (en) * 1976-06-10 1978-02-14 Pei, Inc. Burners for flame jet drill
US4076082A (en) * 1976-02-20 1978-02-28 Messerschmitt-Bolkow-Blohm Gmbh Thermal drilling device
US4190121A (en) * 1976-02-20 1980-02-26 Messerschmitt-Bolkow-Blohm Gmbh Thermal drilling device
US5771984A (en) * 1995-05-19 1998-06-30 Massachusetts Institute Of Technology Continuous drilling of vertical boreholes by thermal processes: including rock spallation and fusion
US20040091830A1 (en) * 2002-04-19 2004-05-13 Ws Warmeprozesstechnik Gmbh Flameless oxidation burner
WO2007112387A2 (en) 2006-03-27 2007-10-04 Potter Drilling, Inc. Method and system for forming a non-circular borehole
US20090031873A1 (en) * 2007-07-20 2009-02-05 Gieseke Thomas J Explosive Water Jet with Precursor Bubble
US20100089576A1 (en) * 2008-10-08 2010-04-15 Potter Drilling, Inc. Methods and Apparatus for Thermal Drilling

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2327499A (en) * 1941-04-18 1943-08-24 Linde Air Prod Co Process of and apparatus for working mineral materials and the like
US2327508A (en) * 1942-01-07 1943-08-24 Linde Air Prod Co Blowtorch
US2675994A (en) * 1948-03-25 1954-04-20 Union Carbide & Carbon Corp Thermal mineral piercing method and apparatus
US3093197A (en) * 1958-12-09 1963-06-11 Union Carbide Corp Method and apparatus for thermally working minerals and mineral-like materials

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2327499A (en) * 1941-04-18 1943-08-24 Linde Air Prod Co Process of and apparatus for working mineral materials and the like
US2327508A (en) * 1942-01-07 1943-08-24 Linde Air Prod Co Blowtorch
US2675994A (en) * 1948-03-25 1954-04-20 Union Carbide & Carbon Corp Thermal mineral piercing method and apparatus
US3093197A (en) * 1958-12-09 1963-06-11 Union Carbide Corp Method and apparatus for thermally working minerals and mineral-like materials

Cited By (18)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3322213A (en) * 1964-03-31 1967-05-30 Union Carbide Corp Thermal mechanical mineral piercing
US3344870A (en) * 1965-03-19 1967-10-03 Hughes Tool Co Reamer for jet piercer
US4076082A (en) * 1976-02-20 1978-02-28 Messerschmitt-Bolkow-Blohm Gmbh Thermal drilling device
US4190121A (en) * 1976-02-20 1980-02-26 Messerschmitt-Bolkow-Blohm Gmbh Thermal drilling device
US4073351A (en) * 1976-06-10 1978-02-14 Pei, Inc. Burners for flame jet drill
US5771984A (en) * 1995-05-19 1998-06-30 Massachusetts Institute Of Technology Continuous drilling of vertical boreholes by thermal processes: including rock spallation and fusion
US20040091830A1 (en) * 2002-04-19 2004-05-13 Ws Warmeprozesstechnik Gmbh Flameless oxidation burner
US7029271B2 (en) * 2002-04-19 2006-04-18 Ws Warmeprozesstechnik Gmbh Flameless oxidation burner
WO2007112387A2 (en) 2006-03-27 2007-10-04 Potter Drilling, Inc. Method and system for forming a non-circular borehole
US20080093125A1 (en) * 2006-03-27 2008-04-24 Potter Drilling, Llc Method and System for Forming a Non-Circular Borehole
US20110174537A1 (en) * 2006-03-27 2011-07-21 Potter Drilling, Llc Method and System for Forming a Non-Circular Borehole
US20090031873A1 (en) * 2007-07-20 2009-02-05 Gieseke Thomas J Explosive Water Jet with Precursor Bubble
US7926587B2 (en) * 2007-07-20 2011-04-19 The United States Of America As Represented By The Secretary Of The Navy Explosive water jet with precursor bubble
US20100089576A1 (en) * 2008-10-08 2010-04-15 Potter Drilling, Inc. Methods and Apparatus for Thermal Drilling
US20100089574A1 (en) * 2008-10-08 2010-04-15 Potter Drilling, Inc. Methods and Apparatus for Wellbore Enhancement
US20100089577A1 (en) * 2008-10-08 2010-04-15 Potter Drilling, Inc. Methods and Apparatus for Thermal Drilling
US20100218993A1 (en) * 2008-10-08 2010-09-02 Wideman Thomas W Methods and Apparatus for Mechanical and Thermal Drilling
US8235140B2 (en) 2008-10-08 2012-08-07 Potter Drilling, Inc. Methods and apparatus for thermal drilling

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