by means expanded or contracted by pressure applied through the medium of a fluid or quasi- fluid

Industry

  • CPC
  • E21D15/30
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Patents Grantslast 30 patents

  • Information Patent Grant

    Mine roof support, pre-installation assembly for same, and method o...

    • Patent number 11,136,887
    • Issue date Oct 5, 2021
    • Burrell Mining Products, Inc.
    • Don C. Abel
    • E21 - EARTH DRILLING MINING
  • Information Patent Grant

    Mine roof support, pre-installation assembly for same, and method o...

    • Patent number 10,822,948
    • Issue date Nov 3, 2020
    • Burrell Mining Products, Inc.
    • Don C. Abel
    • E21 - EARTH DRILLING MINING
  • Information Patent Grant

    Load support drum with resilient core member

    • Patent number 10,774,641
    • Issue date Sep 15, 2020
    • Micon
    • David A. Hussey
    • E21 - EARTH DRILLING MINING
  • Information Patent Grant

    Prestressing of mine props

    • Patent number 5,669,739
    • Issue date Sep 23, 1997
    • HL&H Timber Products (Proprietary) Limited
    • Graham Heath Clarke
    • E21 - EARTH DRILLING MINING
  • Information Patent Grant

    3220686

    • Patent number 3,220,686
    • Issue date Nov 30, 1965
    • E21 - EARTH DRILLING MINING
  • Information Patent Grant

    2938699

    • Patent number 2,938,699
    • Issue date May 31, 1960
    • E21 - EARTH DRILLING MINING
  • Information Patent Grant

    2928643

    • Patent number 2,928,643
    • Issue date Mar 15, 1960
    • E21 - EARTH DRILLING MINING
  • Information Patent Grant

    2895454

    • Patent number 2,895,454
    • Issue date Jul 21, 1959
    • E21 - EARTH DRILLING MINING
  • Information Patent Grant

    2864148

    • Patent number 2,864,148
    • Issue date Dec 16, 1958
    • E21 - EARTH DRILLING MINING
  • Information Patent Grant

    2369823

    • Patent number 2,369,823
    • Issue date Feb 20, 1945
    • E21 - EARTH DRILLING MINING
  • Information Patent Grant

    2351887

    • Patent number 2,351,887
    • Issue date Jun 20, 1944
    • E21 - EARTH DRILLING MINING

Patents Applicationslast 30 patents