MICHAEL B PITTS
Electrician at County Rd 1129, Midland, TX

4791992, Dec 20, 1988

Aug 18, 1987

7/086569

Donald R. Greenlee - Cedar Hill TX
Michael W. Pitts - Midland TX

Dresser Industries, Inc. - Dallas TX

E21B 33128, E21B 3313

166387

Disclosed is a packer (32) responsive to a first hydraulic pressure for setting the packer (32) within a casing (16), and responsive to a second higher pressure for releasing the packer (32) from the casing (16). The first pressure moves an inner piston (94) which shears a screw (96) to thereby apply a compressive force to elastomeric bands (66, 68). The elastomeric bands (66, 68) bow outwardly and seal the packer (32) to the casing (16). A toothed ratchet ring (135) engages with respective teeth (114,122) of the inner piston (94) and an outer cylinder piston (90) to permit one-way movement of the inner piston (94). The packer (32) is thereby set and the hydraulic pressure can be reduced. The packer (32) is released from its sealing engagement with the casing (16) by applying a second greater hydraulic pressure which shears a screw (92), thereby allowing the outer cylindrical piston (90) to move downwardly. The inner piston (94) also moves downwardly, thereby removing the compressive force applied to the elastomeric bands (66, 68) and thus releasing the packer (32) from the casing (16).

4718496, Jan 12, 1988

Jan 5, 1987

7/000602

Charles R. Tompkins - Midland TX
Michael Pitts - Midland TX

Dresser Industries, Inc. - Dallas TX

E21B 33124, E21B 33129

166387

Apparatus for isolating a formation, isolating a damaged section of casing, and for pressure testing the apparatus when located in a cased well bore. The apparatus includes a first packer that is in sealing engagement with the casing for isolating the formation, second and third packers that are spaced to span the damage to the casing, a first valve for closing the passageway through the packers, and a second valve for applying pressure between the first and second packers to test the seals formed thereby. Also provided is an improved method for isolating a damaged section of casing, isolating a formation, and pressure testing the apparatus when located in a cased well bore. The method includes extending the aforementioned apparatus into the well bore, closing the first valve to close the flow through the packers, opening a second valve, and applying pressure to test the seals of the first and second packers. The method also includes the step of applying pressure down an annulus formed between a conduit upon which the apparatus is suspended and the casing to test the seal of the upper packer.