3391751

Information

• Patent Grant
• 3391751

• References
• Source

• Patent Number

  3,391,751

• Date Filed

  Not available

• Date Issued

  Tuesday, July 9, 1968
  56 years ago

• CPC

  • E21B17/10 - Wear protectors Centralising devices
  • E02D17/13 - Foundation slots or slits Implements for making these slots or slits
  • E21B4/16 - Plural down-hole drives
  • E21B4/18 - Anchoring or feeding in the borehole
  • E21B10/06 - Roller core bits
  • E21B10/28 - with non-expansible roller cutters
  • E21B10/34 - of roller-cutter type
  • E21B11/06 - with driven cutting chains or similarly driven tools

• US Classifications

  • 175 - Boring or penetrating the earth