发明名称 |
LOW PRESSURE RESPONSIVE DOWNHOLE TOOL WITH FLOATING SHOE RETARDING MEANS |
摘要 |
<p>An annulus pressure responsive downhole tool includes a housing having a power piston slidably disposed therein. First and second pressure conducting passages communicate a well annulus with first and second sides of the power piston. A retarding device is disposed in the second pressure conducting passage for delaying communication of a sufficient portion of an increase in well annulus pressure to the second side of the power piston for a sufficient time to allow a pressure differential across the power piston to move the power piston from a first position to a second position relative to the housing. The retarding device is an annular floating shoe having a large number of O-rings frictionally engaging inner and outer tubular members of said housing. A pressure relief valve is communicated with the second pressure conducting passage between the power piston and the retarding device for relieving from the second pressure conducting passage a volume of fluid sufficient to permit the power piston to travel to its second position. A spring biased pin disposed in the housing engages an indentation in an actuating mandrel attached to said power piston to releasably hold the power piston in its second position.</p> |
申请公布号 |
CA1211035(A) |
申请公布日期 |
1986.09.09 |
申请号 |
CA19840460968 |
申请日期 |
1984.08.14 |
申请人 |
HALLIBURTON COMPANY |
发明人 |
BECK, HAROLD K. |
分类号 |
E21B34/00;E21B34/10;E21B49/00;(IPC1-7):E21B49/02 |
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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