Horizontal trajectories of rotary-drilled holes

Details

• Personal Author:
  Goodman, Tobias W. ; Cervik, Joseph
• Corporate Authors:
  United States. Bureau of Mines
• Description:
  "This Bureau of Mines report investigates the horizontal trajectory of boreholes drilled in coalbeds using the rotary drilling technique. Test holes drilled in coalbeds showed that the path of a borehole in the horizontal plane depends on drilling assembly configuration, drill bit rotation, and coalbed geologic features. An assembly that contained an 18-ft (5.5-M) long drill collar and two centralizers had the best horizontal stability evidenced by trajectories that deviated less than 16 ft. (4.9 M) from a target at 1,000 ft (305 m). Removal of one of the centralizers resulted in a loss of control of hole trajectory in the horizontal plane. Generally, holes tended to turn to the right, presumably because of right-hand rotation of the bit. Deviations from the original bearing line were as much as 200 ft (61 m) or more at a depth of 1,000 ft (305 m)." - NIOSHTIC-2
  
  NIOSH no. 10006100
  
  
• Subjects:
  Occupational Health Safety
• Series:
  Mining Publications
• Subseries:
  Report of Investigations
• Document Type:
  Text
• Genre:
  Report
• CIO:
  National Institute for Occupational Safety and Health (NIOSH)
• Topic:
  Workplace Safety & Health
• Location:
  North America
• Pages in Document:
  11 numbered pages
• NIOSHTIC Number:
  nn:10006100
• Collection(s):
  National Institute for Occupational Safety and Health
• Main Document Checksum:
  urn:sha-512:5a9246243cff97f7f9104a0d9b0b87b1b6c779fb0458156e377d04212a0dcc7d751faa358ee702f6346c5bdc5beae11e3c6278b5347b9144c82aa625eeb7ba38
• Download URL:
  https://stacks.cdc.gov/view/cdc/9591/cdc_9591_DS1.pdf
• File Type:
  [PDF - 554.81 KB ]