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Method and System For Minimizing Circulating Fluid Loss During Drilling Of A Well Bore By Using a Heated Circulating Fluid

IP.com Disclosure Number: IPCOM000008108D
Publication Date: 2002-May-17
Document File: 21 page(s) / 2M

Publishing Venue

The IP.com Prior Art Database

Related People

Joe Schmidt: AUTHOR [+4]

Abstract

A method and system for minimizing circulating fluid loss during drilling of a well bore and other well service operations is disclosed.  A circulating fluid, ie. mud, is heated prior to being used to flush cuttings from a well bore which is being drilled into a subterranean formation.  Consequently, the region of the formation in contact with heated circulating fluid is maintained at a relatively higher temperature than if a non-heated circulating fluid were used.  This region is constrained or bound by the surrounding formation such that region is maintained  in a relatively greater state of compressive stress than it would be at a lower temperature.  The enhanced compressive state of this region of the formation inhibits the growth and/or opening of fractures.  Consequently, loss of circulating fluid through these fractures during drilling is limited as compared to what losses would be using a lower temperature circulating fluid.

This text was extracted from a Microsoft PowerPoint presentation.
This is the abbreviated version, containing approximately 33% of the total text.

Slide 1 of 21

Mud Temperature Effects on Drilling Lost Returns

For Deepwater Wells

Joe Schmidt, Manny Gonzalez, Ben Bloys, Greg Pepin


Slide 2 of 21

Summary of Invention

A method and system for minimizing circulating fluid loss during drilling of a well bore is disclosed.  A circulating fluid, ie. mud, is heated prior to being used to flush cuttings from a well bore which is being drilled into a subterranean formation.  Consequently, the region of the formation in contact with heated circulating fluid is maintained at a relatively higher temperature than if a non-heated circulating fluid were used.  This region is constrained or bound by the surrounding formation such that region is maintained  in a relatively greater state of compressive stress than it would be at a lower temperature.  The enhanced compressive state of this region of the formation inhibits the growth and/or opening of fractures.  Consequently, loss of circulating fluid through these fractures during drilling is limited as compared to what losses would be using a lower temperature circulating fluid.


Slide 3 of 21

Summary of Invention (Cont.)

A drilling system includes a drill string and drill bit used to drill a well bore in a subterranean formation.  The system further includes casing to line the well bore.  Circulating fluid is used to cool and lubricate the drill bit during drilling.  Also, the circulating fluid is used to flush cuttings drilled from the subterranean formation.  A heating system is used to increase the temperature of the circulating fluids during the drilling operation.  Accordingly, the region of the subterranean formation surrounding the well bore which is in contact with the heated circulating fluid is held at a higher temperature than it would be if contacted with a lower temperature circulating fluid.  This region, bound by the surrounding formation, is therefore also held in a relatively higher state of compressive stress than it would be at a lower temperature.  Consequently, the growth of fractures in the region is inhibited and loss of circulating fluids reduced as compared to using lower temperature circulating fluids.


Slide 4 of 21

Summary of Invention (Cont.)

The heated circulating fluid may be at a higher or lower temperature than the region of the adjacent formation in contact with the circulation fluid.  However, by heating the circulating fluid to a higher temperature, the adjacent formation is still kept at a higher temperature and compressive stress state than if non-heated circulating fluids were used.

The heating system may be a heat exchanger.  Another alternative is to use chemicals which will induce exothermic reactions to increase the temperature of the circulating fluids.  Another option is to increase the friction between the circulating fluids and its surrounding passages to create heat and increase the temperature of the circulating fluid.


Slide 5 of 21

Summary of Invention (Cont.)

The drilling system may be used in conjunction with drilling dee...