14 NEW DRILL CONCEPTS

APPLICATIONS OF A LASER ACTIVATED DRILL TO ROCK DRILLING ARE DISCUSSED. SOME OF THESE APPLICATIONS ARE: (1) BLAST- HOLE DRILLING, (2) BIG-HOLE DRILLING, (3) BUILDING STONE MINING, (4) PRE-SHEARING, AND (5) KERF CUTTING. METHODS USING ELECTRICAL ENERGY FOR BORE-HOLE DRILLING DISCUSSED ARE: (1) CARBON-ARC, (2) COVERED METAL (ELECTRODE) -ARC, (3) OXYGEN OR AIR CARBON-ARC, (4) GAS SHIELDED METAL OR TUNGSTEN-ARC AND (5) PLASMA ARC. THE TERRA-JETTER DRILL UTILIZES SUPERHEATED STEAM AND LIQUID NITROGEN TO RIP AND TEAR ITS WAY THROUGH ROCK. OTHER SUGGESTED APPLICATIONS ARE: DRILLING FOR FOUNDATIONS, WATER WELLS AND TUNNELS. THE RUSSIANS USE A SHOCK-WAVE DRILL TO DELIVER CRUSHING LOADS TO ROCK BY SHOCK-WAVES WHICH TRAVEL THROUGH LIQUID. THE PRINCIPAL OF THE VIBRATORY DRILL IS TO DELIVER MORE BLOWS PER UNIT OF TIME FOR PENETRATION OF ROCK. A DRILL CAPABLE OF FREQUENCIES UP TO 1,400 PER SECOND HAS BEEN REPORTED IN ONE CASE. THE FORCE MAY BE USED DIRECTLY TO FRACTURE THE ROCK OR IT MAY VIBRATE A RESONANT LENGTH OF DRILL STEEL ATTACHED TO THE BIT. PLASMA IS SUGGESTED AS A POTENTIAL ENERGY SOURCE FOR DRILLING. ADVANTAGES OF THE HYDROGEN-PLASMA TORCH FOR THERMAL ROCK REMOVAL LISTED ARE: (1) THE TEMPERATURE AND HEAT TRANSFER COULD BE OBTAINED TO SPALL OR MELT ROCKS OR POSSIBLY VAPORIZE THEM, (2) ELECTRICAL REQUIREMENTS WOULD NOT CREATE A SAFETY HAZARD, AND (3) GASES PRODUCED, MOSTLY WATER VAPOR, PROBABLY WOULD PRESENT NO UNUSUAL VENT PROBLEMS. THERMAL DRILLING IS DISCUSSED FOR APPLICATIONS IN OIL WELL DRILLING. THE THERMAL BIT CONSISTS ESSENTIALLY OF A TUNGSTEN OR MOLYBDENUM FACE, AN INNER BASE OF A BORON- NITRIDE ELECTRICAL INSULATOR AND HEAT CONDUCTOR, A TUNGSTEN HEATING ELEMENT, AND A BORON-NITRIDE BACKING PLATE. PERCUSSION DRILLING IS DISCUSSED WITH THE PREDICTION THAT THE USE OF MORE AIR PRESSURE AVAILABLE FROM NEW COMPRESSORS, WILL INCREASE PENETRATION OF PERCUSSION DRILLS.

• Supplemental Notes:
  • Vol 167, No 6, PP 239-258, 8 FIG, 6 PHOT
• Publication Date: 1966-6

Media Info

• Serial:
  • Engineering and Mining Journal
  • Publisher: McGraw-Hill, Incorporated

Subject/Index Terms

• TRT Terms: Air; Air compressors; Boreholes; Carbon; Drilling; Electric arcs; Electrodes; Hydrogen; Lasers; Liquid nitrogen; Metals; Oil wells; Oxygen; Rock drilling; Shock waves; Steam; Thermal power generation; Tungsten; Vibration devices
• Old TRIS Terms: Carbon arcs; Percussion drilling; Plasma arc; Rock drills; Superheat; Thermal power; Vibrators
• Subject Areas: Highways; Vehicles and Equipment;

Filing Info

• Accession Number: 00219286
• Record Type: Publication
• Files: TRIS
• Created Date: May 6 1994 12:00AM