TREA

David P. Herd

Follow

Person

  • Kingwood, TX, US
People

Patents Grantslast 30 patents

  • Information Patent Grant

    Pressure-balanced gate for split-gate valve
    • Patent number 4,685,655
    • Issue date Aug 11, 1987
    • Smith International, Inc.
    • David P. Herd
    • F16 - ENGINEERING ELEMENTS AND UNITS GENERAL MEASURES FOR PRODUCING AND MAINT...
  • Information Patent Grant

    Seal
    • Patent number 4,451,047
    • Issue date May 29, 1984
    • Smith International, Inc.
    • David P. Herd
    • F16 - ENGINEERING ELEMENTS AND UNITS GENERAL MEASURES FOR PRODUCING AND MAINT...
  • Information Patent Grant

    High pressure gate valve with preloaded, stacked, solid lubricated...
    • Patent number 4,340,204
    • Issue date Jul 20, 1982
    • Smith International, Inc.
    • David P. Herd
    • F16 - ENGINEERING ELEMENTS AND UNITS GENERAL MEASURES FOR PRODUCING AND MAINT...
  • Information Patent Grant

    Fail-safe, non-pressure locking gate valve
    • Patent number 4,294,284
    • Issue date Oct 13, 1981
    • Smith International, Inc.
    • David P. Herd
    • E21 - EARTH DRILLING MINING
  • Information Patent Grant

    Single double backseat
    • Patent number 4,272,055
    • Issue date Jun 9, 1981
    • McEvoy Oilfield Equipment Company
    • David P. Herd
    • F16 - ENGINEERING ELEMENTS AND UNITS GENERAL MEASURES FOR PRODUCING AND MAINT...
  • Information Patent Grant

    Balanced stem fail-safe valve system
    • Patent number RE30115
    • Issue date Oct 16, 1979
    • Exxon Production Research Company
    • David P. Herd
    • 251 - Valves and valve actuation
  • Information Patent Grant

    High pressure valve
    • Patent number 4,029,294
    • Issue date Jun 14, 1977
    • McEvoy Oilfield Equipment Co.
    • John Walton McCaskill
    • F16 - ENGINEERING ELEMENTS AND UNITS GENERAL MEASURES FOR PRODUCING AND MAINT...
  • Information Patent Grant

    Balanced stem fail-safe valve system
    • Patent number 3,933,338
    • Issue date Jan 20, 1976
    • Exxon Production Research Company
    • David P. Herd
    • F16 - ENGINEERING ELEMENTS AND UNITS GENERAL MEASURES FOR PRODUCING AND MAINT...