3491843

Information

• Patent Grant
• 3491843

• References
• Source

• Patent Number

  3,491,843

• Date Filed

  Not available

• Date Issued

  Tuesday, January 27, 1970
  54 years ago

• CPC

  • E21B4/16 - Plural down-hole drives
  • E21B7/005 - with helical conveying means
  • E21B7/28 - Enlarging drilled holes
  • E21B17/22 - Rods or pipes with helical structure
  • E21D9/124 - Helical conveying means therefor

• US Classifications

  • 175 - Boring or penetrating the earth