3620024

Information

• Patent Grant
• 3620024

• References
• Source

• Patent Number

  3,620,024

• Date Filed

  Not available

• Date Issued

  Tuesday, November 16, 1971
  53 years ago

• CPC

  • E21F16/00 - Drainage
  • E02B11/00 - Drainage of soil
  • E21F16/02 - of tunnels

• US Classifications

  • 405 - Hydraulic and earth engineering
  • 052 - Static structures
  • 138 - Pipes and tubular conduits