发明名称 |
SIKKERHETSVENTIL FOR UNDERGRUNNS-ROERLEDNING |
摘要 |
<p>There is disclosed a subsurface tubing safety valve of the type having a flapper swingable between an open position to one side of its bore and a closed position over a seat about its bore. A seal ring retained in a groove about the seat has a protruding lip which is initially engaged by the flapper as it is swung toward the seating surface of the seat.</p> |
申请公布号 |
NO931558(A) |
申请公布日期 |
1993.11.02 |
申请号 |
NO19930001558 |
申请日期 |
1993.04.29 |
申请人 |
AVA INTERNATIONAL CORPORATION |
发明人 |
AKKERMAN, NEIL HOOVER;BUCKNER, THOMAS ROBERT |
分类号 |
E21B34/00;E21B34/06;E21B34/10;(IPC1-7):E21B34/06 |
主分类号 |
E21B34/00 |
代理机构 |
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代理人 |
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主权项 |
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地址 |
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