Field testing of a cornering water jet drill
Sandia National Laboratories is developing a drilling system which uses high velocity water jets to make horizontal holes in a coal seam accessed through a vertical borehole. For underground coal gasification (UCG), these horizontal holes can be drilled to create linking paths between vertical process wells. During shake-down tests in Albuquerque, five holes were drilled in a simulated coal seam. The eight to twelve inch diameter holes deviated from their intended trajectories by less than twelve inches in twenty feet. Similar results have been produced during more recent field tests in an open pit coal mine. An exposed coal seam with undisturbed overburden was penetrated to a depth of over seventy feet with maximum deviations of less than four inches vertically and six degrees horizontally. To date, all tests have utilized an elevated platform to permit observation of the cornering mechanism during drilling operations. For all tests to date, the on board logging instrumentation has provided accurate guidance and hole location data. Test results indicate that the drilling system is capable of producing horizontal holes for UCG applications. A proof of concept test is forthcoming that will require the drill to access a coal seam from an underreamed cavity located at the bottom of a vertical borehole. 13 figures.
- Research Organization:
- Sandia National Labs., Albuquerque, NM (USA)
- DOE Contract Number:
- AC04-76DP00789
- OSTI ID:
- 5952229
- Report Number(s):
- SAND-83-1615C; CONF-830827-4; ON: DE83016244
- Country of Publication:
- United States
- Language:
- English
Similar Records
Development testing of a cornering water-jet drill
Testing of a cornering water-jet-drilling system for drilling horizontal holes in coal
Related Subjects
010404* -- Coal
Lignite
& Peat-- Gasification
012000 -- Coal
Lignite
& Peat-- Mining
42 ENGINEERING
420206 -- Engineering-- Mining & Drilling Equipment & Facilities-- (1980-1989)
BOREHOLE LINKING
COAL DEPOSITS
COAL SEAMS
DATA
DIRECTIONAL DRILLING
DRILLING
DRILLING EQUIPMENT
DRILLS
EQUIPMENT
EXPERIMENTAL DATA
FIELD TESTS
GASIFICATION
GEOLOGIC DEPOSITS
HYDROGEN COMPOUNDS
IN-SITU GASIFICATION
IN-SITU PROCESSING
INFORMATION
JET DRILLS
MINERAL RESOURCES
NUMERICAL DATA
OXYGEN COMPOUNDS
PERFORMANCE TESTING
PROCESSING
RESOURCES
SIMULATION
TESTING
THERMOCHEMICAL PROCESSES
WATER