3616650

Information

• Patent Grant
• 3616650

• References
• Source

• Patent Number

  3,616,650

• Date Filed

  Not available

• Date Issued

  Tuesday, November 2, 1971
  53 years ago

• CPC

  • E21D9/1053 - for making a slit along the perimeter of the tunnel profile, the remaining core being removed subsequently
  • E21D9/10 - Making by using boring or cutting machines

• US Classifications

  • 405 - Hydraulic and earth engineering