3850194

Information

• Patent Grant
• 3850194

• References
• Source

• Patent Number

  3,850,194

• Date Filed

  Not available

• Date Issued

  Tuesday, November 26, 1974
  50 years ago

• CPC

  • E21B34/12 - operated by movement of casings or tubings
  • E21B21/10 - Valve arrangements in drilling fluid circulation systems
  • F16K15/181 - for check valves with a hinged closure member
  • F16K15/183 - for ball check valves
  • E21B2034/005 - Flapper valves
  • Y10T137/7783 - Valve closes in responses to reverse flow
  • Y10T137/7855 - Valve seat threaded into a coupling element
  • Y10T137/7856 - Valve seat formed on or carried by a coupling element

• US Classifications

  • 137 - Fluid handling
  • 166 - Wells