2780067

Information

• Patent Grant
• 2780067

• References
• Source

• Patent Number

  2,780,067

• Date Filed

  Not available

• Date Issued

  Tuesday, February 5, 1957
  67 years ago

• CPC

  • E21D17/086 - or articulated type
  • E21D17/01 - characterised by the shape of the cap
  • Y10T292/1022 - Rigid

• US Classifications

  • 405 - Hydraulic and earth engineering
  • 248 - Supports
  • 292 - Closure fasteners
  • 299 - Mining or in situ disintegration of hard material