41
Crary Steven F, Heidler Ralf, Poitzsch Martin E, Esmersoy Cengiz: Apparatus and method for determining a drilling mode to optimize formation evaluation measurements. Schlumberger A Netherl, Schlumberger Services Petrol, Schlumberger Technology, September 1, 1999: EP0939195-A2 (16 worldwide citation)

There are many natural pauses during rotary drilling operations where a portion of the drill string remains stationary. Pauses include drill pipe connections, circulating time, and fishing operations. These pauses are used to obtain formation evaluation measurements that take a long time or that ben ...


42
Le Roy Delage Sylvaine, Bulte Helene, Bellabarba Mario: Self-repairing isolation systems. Schlumberger Services Petrol, Schlumberger Technology, Schlumberger Holdings, Prad Res & Dev, February 18, 2009: EP2025732-A1 (15 worldwide citation)

The present invention discloses a composition for completing a well comprising a pumpable fluid made of a settable material and a reactive material able to swell in contact with liquid and/or gaseous hydrocarbon and/or water and/or carbon dioxide, said reactive material added in a quantity such that ...


43
Shenoy Ramachandra, Chang Shu Kong: Downhole processing of sonic waveform information.. Schlumberger, Schlumberger Services Petrol, Schlumberger Technology, Schlumberger Holdings, June 28, 1995: EP0660136-A2 (14 worldwide citation)

Methods for processing sonic logging data obtained by a sonic imaging tool or an MWD tool are provided. The sonic logging data are bandpass filtered and sampled according to techniques such as integer band decimation, quadrature modulation, and single side band modulation to provide compressed signa ...


44
Bagersh Abdullah A, Bonner Stephen D, Clark Brian, Jundt Jacques, Luling Martin, Rosthal Richard A: Method and apparatus for investigating earth formations.. Schlumberger Holdings, Schlumberger Services Petrol, Schlumberger Technology, Schlumberger, May 5, 1993: EP0540425-A2 (14 worldwide citation)

Apparatus and method are disclosed for determining the resistivity of formations surrounding an earth borehole. An electrically conductive metal body (202), such an a drill collar on a drill string, is movable through the borehole. A transmitting toroidal coil antenna (205) is disposed on the body ( ...


45
Chan Keng Seng, Elmarsafawi Youssef: Cementing compositions and application thereof to cementing oil wells or the like. Schlumberger Services Petrol, Schlumberger Technology, Schlumberger Holdings, Prad Res & Dev, Schlumberger Oilfield Assist, August 2, 2006: EP1686234-A1 (14 worldwide citation)

The invention relates to composition particularly suitable for squeeze cementing operations at temperature above 160 DEG C. This composition comprises an aqueous base, a liquid set-retarder and a solid phase including a blend of micro fine alumina, micro fine silica and a micro fine cementitious mat ...


46
Jelley David John, Jarvis Brian Peter: Drill bit design using neural networks. Schlumberger Holdings, Schlumberger Services Petrol, October 17, 2001: EP1146200-A1 (13 worldwide citation)

The present invention is a method and apparatus which accurately predicts one or more operating characteristics of an earth boring drill bit operated under a set of known operating conditions. A range of operating conditions may be input so that the operating characteristic(s) of the drill bit may b ...


47
Wijnberg Willem: Cable for data transmission and method for manufacturing the same.. Schlumberger, Schlumberger Services Petrol, Schlumberger Technology, Schlumberger Holdings, February 19, 1992: EP0471600-A1 (13 worldwide citation)

A cable for data transmission comprising a core comprising at least one energy transmission line; a jacket enclosing the core; armor strands wound around the jacket; and an embedding elastic structure, surrounding the jacket and designed to receive the armor strands. The cable may be manufactured as ...


48
Guillot Dominique, Maitland Geoffrey, Cooper Iain: Method and apparatus for well construction. Schlumberger Services Petrol, Schlumberger Technology, Schlumberger Holdings, Prad Res & Dev, June 6, 2007: EP1793078-A1 (13 worldwide citation)

A method of constructing a well comprising a borehole drilled through underground formations, comprises: positioning at least one device on the outside of the tubular string (e.g. a drill string or casing string), the device being operable to move between first and second configurations; positioning ...


49
Askew Warren, Eddison Alan: Downhole adjustable stabilizer.. Anadrill Int, Schlumberger Services Petrol, August 5, 1992: EP0497422-A1 (13 worldwide citation)

In accordance with illustrative embodiments of this invention, a downhole adjustable stabilizer includes a sleeve having outwardly extending blades and mounted for limited rotation on a mandrel, vertically aligned sets of radially movable buttons mounted in bores in the blades, and longitudinal flat ...


50
Codazzi Daniel: Method of and apparatus for detecting an influx into a well while drilling.. Anadrill Int, Schlumberger Services Petrol, January 15, 1992: EP0466229-A1 (13 worldwide citation)

Gas influx into a wellbore, which is commonly referred to as a "kick", is detected during active drilling of the borehole. One embodiment of the present invention is based upon the existence of standing wave patterns generated by pressure oscillations of the drilling rig mud pumps. The standing wave ...