Yogesh R Dave

US Patent:

51955881, Mar 23, 1993

Filed:

Jan 2, 1992

Appl. No.:

7/815982

Inventors:

Yogesh S. Dave - Stamford CT

Assignee:

Schlumberger Technology Corporation - New York NY

International Classification:

E21B 3313
E21B 4311
E21B 4908

US Classification:

166255

Abstract:

An apparatus is disclosed for perforating, testing, and repairing casing in an earth borehole. A device is moveable through the casing. The device can be mounted on a wireline, on tubing, or on both. A perforator is mounted in the device for producing a perforation in the casing. The device will also generally include components for hydraulic testing/sampling from the formations behind the casing. A plugger is mounted in the device for plugging the perforation with a solid plug or a non-solid sealant.

US Patent:

52691802, Dec 14, 1993

Filed:

Sep 17, 1991

Appl. No.:

7/761213

Inventors:

Yogesh S. Dave - Stamford CT
T. S. Ramakrishnan - Bethel CT

Assignee:

Schlumberger Technology Corp. - New York NY

International Classification:

E21B 4900
G01N 1508

US Classification:

73152

Abstract:

A borehole tool has a source probe in fluid contact with the borehole wall, a fluid flow line for bringing fluids to and from the source probe, two injection fluid chambers containing clean oil and clean water and in fluid contact with the fluid flow line, at least one sample chamber for receiving fluid from the formation, valves for selectively routing the formation fluids and the clean oil and water through the fluid flow line, at least one pressure controller for controlling whether fluid is to be injected or withdrawn from the formation via the source probe, and a pressure gauge for measuring the pressure seen at the source probe. Permeability measurements are made by sequentially injecting one clean fluid into the formation, followed by a cleaning of the line with the other fluid which was not injected, followed by the injection of the other fluid into the formation. The order in which the oil and water are injected is based on the type of mud used for drilling. Using the sequential injection preceded and separated by cleaning, end point effective and relative permeability determinations are made by measuring the pressure seen at the probe during steady-state injection conditions of known flow rate in order to calculate mobility of the fluid phase being injected; the mobility being related to the end point effective permeability via the viscosity of the liquid being injected.

US Patent:

55178545, May 21, 1996

Filed:

Apr 29, 1994

Appl. No.:

8/236356

Inventors:

Richard A. Plumb - North Tarrytown NY
Yogesh S. Dave - Stamford CT

Assignee:

Schlumberger Technology Corporation - New York NY

International Classification:

E21B 4900
E21B 4910

US Classification:

73151

Abstract:

A modular sonde may be configured in various ways for measurements in open or cased boreholes. The sonde is conveyed on an electric wireline with or without a coiled tubing for conveying hydraulic energy from the surface. Modules common to the configurations include telemetry electronics, orientation, hydraulic energy accumulator, fluid chambers, hydraulic power, pumpout, and flow control. Each configuration has a stress/rheology module suited to the borehole situation. An open-hole sonde configuration has a stress/rheology module with an instrumented, inflatable packer module, an orienting module, and a probe module. A second open-hole sonde configuration has a stress/rheology module with an instrumented straddle-packer assembly. A cased-hole sonde configuration has a gunblock assembly, a gunblock orienting module hydraulics for formation pretest and hydraulics for stressing the formation to obtain data related to formation stress characteristics. A second cased-hole sonde configuration has a straddle-packer assembly, a casing perforation device in the straddle interval, and hydraulics for stressing the formation to obtain data related to formation stress characteristics.

US Patent:

53536371, Oct 11, 1994

Filed:

Jun 9, 1992

Appl. No.:

7/896116

Inventors:

Richard A. Plumb - North Tarrytown NY
Yogesh S. Dave - Stamford CT

International Classification:

E21B 4700

US Classification:

73151

Abstract:

A modular sonde may be configured in various ways for measurements in open or cased boreholes. The sonde is conveyed on an electric wireline with or without a coiled tubing for conveying hydraulic energy from the surface. Modules common to the configurations include telemetry electronics, orientation, hydraulic energy accumulator, fluid chambers, hydraulic power, pumpout, and flow control. Each configuration has a stress/rheology module suited to the borehole situation. An open-hole sonde configuration has a stress/rheology module with an instrumented, inflatable packer module, an orienting module, and a probe module. A second open-hole sonde configuration has a stress/rheology module with an instrumented straddlepacker assembly. A cased-hole sonde configuration has a gunblock assembly, a gunblock orienting module hydraulics for formation pre-test and hydraulics for stressing the formation to obtain data related to formation stress characteristics. A second cased-hole sonde configuration has a straddle-packer assembly, a casing perforation device in the straddle interval, and hydraulics for stressing the formation to obtain data related to formation stress characteristics.