Measuring and testing – Borehole or drilling – During drilling
Reexamination Certificate
2000-09-12
2002-05-21
Williams, Hezron (Department: 2856)
Measuring and testing
Borehole or drilling
During drilling
C073S152460, C073S152270, C166S250070, C166S254200
Reexamination Certificate
active
06389890
ABSTRACT:
BACKGROUND OF THE INVENTION
1. Technical Field
The invention relates generally to electrical downhole tools which are employed for various downhole oil-field applications, e.g., firing shaped charges through a casing and setting a packer in a wellbore. More particularly, the invention relates to a pressure-actuated downhole tool and a method and an apparatus for generating pressure signals which may be interpreted as command signals for actuating the downhole tool.
2. Background Art
Electrical downhole tools which are used to perform one or more operations in a wellbore may receive power and command signals through conductive logging cables which run from the surface to the downhole tools. Alternatively, the downhole tool may be powered by batteries, and commands may be preprogrammed into the tool and executed in a predetermined order over a fixed time interval, or command signals may be sent to the tool by manipulating the pressure exerted on the tool. The downhole pressure exerted on the tool is recorded using a pressure gage, and downhole electronics and software interpret the pressure signals from the pressure gage as executable commands. Typically, the downhole pressure exerted on the tool is manipulated by surface wellhead controls or by moving the tool over set vertical distances and at specified speeds in a column of fluid. However, generating pressure signals using these typical approaches can be difficult, take excessively long periods of time to produce, or require too much or unavailable equipment. Thus, it would be desirable to have a means of quickly and efficiently generating pressure signals.
SUMMARY OF THE INVENTION
In general, in one aspect, a hydraulic strain sensor for use with a downhole tool comprises a housing having two chambers with a pressure differential between the two chambers. A mandrel disposed in the housing is adapted to be coupled to the tool such that the weight of the tool is supported by the pressure differential between the two chambers. A pressure-responsive member in communication with one of the chambers is arranged to sense pressure changes in the one of the chambers as the tool is accelerated or decelerated and to generate signals representative of the pressure changes.
Other aspects and advantages of the invention will be apparent from the following description and the appended claims.
REFERENCES:
patent: 2681567 (1954-06-01), Widess
patent: 3465582 (1969-09-01), Richter, Jr. et al.
patent: 3627065 (1971-12-01), Murphy
patent: 3855853 (1974-12-01), Claycomb
patent: 3991610 (1976-11-01), Rakar et al.
patent: 4157528 (1979-06-01), Shuck et al.
patent: 4266606 (1981-05-01), Stone
patent: 4294318 (1981-10-01), Desbrandes et al.
patent: 4359898 (1982-11-01), Tanguy et al.
patent: 4524324 (1985-06-01), Dickinson, III
patent: 4608861 (1986-09-01), Wachtler et al.
patent: 4676310 (1987-06-01), Scherbatskoy et al.
patent: 4693335 (1987-09-01), Almon
patent: 4760741 (1988-08-01), Koopmans et al.
patent: 4805449 (1989-02-01), Das
patent: 4860580 (1989-08-01), DuRocher
patent: 4896722 (1990-01-01), Upchurch
patent: 5048344 (1991-09-01), Herget et al.
patent: 5050690 (1991-09-01), Smith
patent: 5065619 (1991-11-01), Myska
patent: 5099700 (1992-03-01), Morin et al.
patent: 5184508 (1993-02-01), Desbrandes
patent: 5205164 (1993-04-01), Steiger et al.
patent: 5329811 (1994-07-01), Schultz et al.
patent: 5343963 (1994-09-01), Bouldin et al.
patent: 5517854 (1996-05-01), Plumb et al.
patent: 5623993 (1997-04-01), Van Buskirk et al.
patent: 5900545 (1999-05-01), Sacks et al.
patent: 6055213 (2000-04-01), Rubbo et al.
patent: 6209391 (2001-04-01), Dallas
Model Slickline Initiation Device; Petroleum Engineering Services Limited; Oct. 4, 1995; pp. 1-11.
Hansen Merlin D.
Sweetland Matthew
Schlumberger Technology Corporation
Trop Pruner & Hu P.C.
Wiggins David J.
Williams Hezron
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