Mike Edgar, Greg Horton: Reverse cementing float shoe. Schlumberger Technology Corporation, Stephen Schlather, Robin Nava, October 12, 2004: US06802374 (71 worldwide citation)

A float shoe comprising an upper section having a casing connection at an upper end thereof, and a lower section slidably coupled to the upper section, the lower section comprising a closed lower end and having at least one port disposed therein.

Hubertus V Thomeer, James Michael Costley, Randolph J Sheffield, David M Eslinger, Marc Allcorn, Mark C Oettli: Downhole machining of well completion equipment. Schlumberger Technology Corporation, Stephen Schlather, Brigitte L Jeffery, John J Ryberg, August 27, 2002: US06439313 (56 worldwide citation)

A method of machining a workpiece in a subterranean wellbore comprises the steps of: (a) providing a workpiece that comprises (1) a first section that comprises a first material, and (2) a second section that comprises a second material, the second section forming at least one surface of the workpie ...

Joseph A Ayoub, John P Crawshaw, Paul W Way: Self-diverting resin systems for sand consolidation. Schlumberger Technology Corporation, Stephen Schlather, Catherine Menes, Brigitte Jeffery, October 14, 2003: US06632778 (49 worldwide citation)

Herein is described a fluid that is useful in consolidating a formation without the use of a gravel pack and screen. In particular, the fluid is useful in consolidating heterogeneous formations where the permeability is not uniform over-the total formation thickness, e.g. a formation having at least ...

Bobby D Poe: Method and apparatus for effective well and reservoir evaluation without the need for well pressure history. Schlumberger Technology Corporation, Stephen Schlather, Robin Nava, January 11, 2005: US06842700 (38 worldwide citation)

A method for evaluating well performance includes deriving a reservoir effective permeability estimate from data points in a production history, wherein the data points include dimensional flow rates and dimensional cumulative production, at least one of the data points has no sand face flowing pres ...

Timothy G J Jones, Gary J Tustin: Hydrophobically modified polymers for water control. Schlumberger Technology Corporation, Stephen Schlather, Robin Nava, October 12, 2004: US06803348 (37 worldwide citation)

The use of a hydrophobically modified water soluble polymer is described capable of being chemically cross-linked so as to produce a stable gel for blocking a water-bearing formation from a hydrocarbon-producing well. The polymer is essentially linear having hydrophilic side groups located at random ...

Demosthenis Georgeou Pafitis, Stephen Nigel Davies, Geoffrey Colin Maitland: Thixotropic materials. Schlumberger Technology Corporation, Robin C Nava, Stephen Schlather, Thomas O Mitchell, August 28, 2001: US06279655 (35 worldwide citation)

A settable thixotropic material comprises a thixotrope and a settable substance, the material being capable of gelling reversibly in a gelling time of less than 60 seconds. The thixotrope conveniently comprises a fine grained clay, especially smectite clays, e.g. hectorites. It is preferred to use s ...


Harjit S Kohli, Elizabeth A Mackenzie, Gary L Rogers, Jean Louis Pessin, Erik Rhein Knudsen: Mixing and pumping vehicle. Schlumberger Technology Corporation, Stephen Schlather, Catherine Menes, December 3, 2002: US06488088 (33 worldwide citation)

A vehicle, such as a truck, includes mixing and pumping equipment for mixing a liquid and a particulate material (e.g., cement) and for pumping the mixture. One application is to pump the mixture into a wellbore for cementing a casing or liner to the wellbore inner wall. The vehicle includes a cab, ...

Yarom Polsky, Rod Shampine, Terry McCafferty: Modular coiled tubing system for drilling and production platforms. Schlumberger Technology Corporation, Stephen Schlather, Robin Nava, July 20, 2004: US06763890 (29 worldwide citation)

A modular work system permits Rig Up time to be substantially reduced by reducing the number of crane lifts required to offload equipment for a transport boat or vehicle. This is achieved by developing transport skids capable of holding multiple system components. The number of equipment components ...

Sylvaine Le Roy Delage, Marc Thiercelin: Cementing compositions and applications of such compositions for cementing oil wells or the like. Schlumberger Technology Corporation, Stephen Schlather, Thomas O Mitchell, Robin Nava, June 1, 2004: US06742592 (26 worldwide citation)

The present invention provides cementing compositions for an oil well or the like, comprising an hydraulic binder, dense particles with a density higher than the density of the hydraulic binder, and reinforcing particles with a density of less than 1.5 g/cm