Drilling Tool Steering Device

• US 20090166089A1
• Filed: 03/26/2007
• Published: 07/02/2009
• Est. Priority Date: 03/27/2006
• Status: Active Grant

• Current Assignee: Millet Francois
• Original Assignee: Millet Francois
• Inventors: Millet, Francois
• Granted Patent: US 8,887,834 B2
• Time in Patent Office: Days
• US Class Current: 175/61
• CPC Class Codes: E21B 7/067 with means for locking sections of a pipe or of a guide for a shaft in angular relation, e.g. adjustable bent sub

Abstract

The invention concerns a drilling tool steering device, characterized in that it contains, consecutively from upstream to downstream, a main body (1) and a steerable housing (2), joined respectively by at least one connection of pivot, sliding pivot, ball joint or annular linear type forming a first bearing (4), and at least one pivot connection forming a second bearing (5), to a bendable or flexible transmission shaft (3) which crosses them longitudinally, while a connection of pivot, sliding pivot, annular linear or ball joint type forming a third bearing (6) between said transmission shaft and the main body (1) is arranged in proximity to the end of said main body situated in the direction of the steerable case, and while steering is carried out thanks to means acting as a deflection system (7) for the essentially radial relative displacement of the main body (1) in relation to the steerable housing (2) in proximity to their interface, the said main body being optionally equipped on its periphery with bearing pads (9) of diameter less than or equal to the diameter of the drilling tool/bit (16), and the said steerable case being optionally equipped on its periphery with bearing pads (10a) of diameter less than or equal to the diameter of the drilling tool/bit (16) toward its end situated in the direction of the drilling tool/bit, and with fixed or expandable pads or clamps toward its end situated in the direction of the main body (1). Application to boreholes necessitating trajectory control.

Claims

1. Drilling tool steering device comprising, consecutively from upstream to downstream, a main body (1) and a steerable housing (2), joined respectively by at least one connection of pivot, sliding pivot, ball joint or annular linear type forming a first bearing (4), and at least one pivot connection forming a second bearing (5), to a bendable or flexible transmission shaft (3) which crosses them longitudinally, whereas a connection of pivot, sliding pivot, annular linear or ball joint type forming a third bearing (6) between said transmission shaft and the main body (1) is arranged in proximity to the end of said main body situated in the direction of the steerable housing, and whereas steering is carried out thanks to means acting as a deflection system (7) for the essentially radial relative displacement of the main body (1) in relation to the steerable housing (2) in proximity to their interface,

said main body being optionally equipped on its periphery with bearing pads (9) of diameter less than or equal to the diameter of the drilling tool/bit (16), and

said steerable housing being optionally equipped on its periphery with bearing pads (10a) of diameter less than or equal to the diameter of the drilling tool/bit (16) toward its end situated in the direction of the drilling tool/bit, and with fixed or expandable pads or clamps toward its end situated in the direction of the main body (1).

2. Device according to claim 1, wherein the pivot connection between the main body (1) and the shaft (3) is made by means (A) of an upper bearing (4) of pivot, sliding pivot, ball joint or annular linear type, and (B) of a center bearing (6) of pivot, sliding pivot, annular linear or ball joint type, those two bearings being situated in proximity to both the respective ends of the main body (1), whereas the center bearing (6) is in the direction of the steerable housing (2), and

wherein the pivot connection between the steerable housing and the shaft (3) is made by means of a lower bearing (5), situated in proximity to the end of the steerable housing (2) located in the direction of the drilling tool/bit (16).

3. Device according to claim 1, wherein the deflection system (7) is designed to make bending possible by essentially radial displacement of the upper end of the steerable housing (2) in relation to the lower end of the main body (1), by bearing either on the transmission shaft (3) or main body (1) or on the wall of the well drilled.

4. Device according to claim 1, wherein said bearings (4, 5, 6) consist of roller bearings selected from the group consisting of, ball bearings, tapered roller bearings, cylindrical roller bearings or needle bearings, advantageously prestressed, or of hydrodynamic bearings, notably oil or drilling mud bearings, or of any combination of same.

5. Device according to claim 1, wherein the device is designed to constitute a dynamic connection and is equipped, at the end of the steerable housing (2) situated in the direction of the deflection system (7), with clamps or blades intended to permit, on deflection of the shaft (3), locking or braking of the device on rotation by grooving of the wall of the borehole.

6. Device according to claim 1, wherein the shaft (3) is a monobloc tubular transmission shaft made of composite materials or alloys having a high ratio between the fatigue limit under reversed bending stress and the Young'"'"'s modulus, and said shaft does not contain sudden section changes, while just the ends of the shaft can optionally be threaded and can present joint grooves, and while the components such as roller bearings, annular gear and others are fitted on the shaft by thermal or mechanical hooping.

7. Device according to claim 1, wherein the respectively low and high connections are joined with the shaft (3) by threading combined with a hydraulically controlled hoop, ensuring the transmission of tensile and compressive axial stresses and torque to the drilling tool, respectively.

8. Device according to claim 1, further comprising a front scraper joint and gasket assembly or a metal, plastic and/or laminated elastomer bellow that ensures tightness at the interface between the main body (1) and the steerable housing (2).

9. Device according to claim 1, wherein the deflection system (7) is formed, in the case of a static connection device, by two radially eccentric rings, a ball joint and a sliding pivot connection, as well as by a prestressed spring, deflection then being obtained by differential rotation of the two rings.

10. Device according to claim 1, wherein the main body (1) integrates a detector of rotation of the boring rods. that is advantageously entirely mechanical or in “

rotary mode with straight shaft”

for an autonomous activation of the case, without resorting to a surface/bottom transmission.

11. Device according to claim 1, further comprising one or more generators (19a) in a barrel arrangement around the shaft (3) and driven by the latter by means of a pinion-step-up gear assembly (18), the said generators being preferably coupled to one or more rectifiers that can be coupled in series or in parallel for a wide speed range, and a plurality of high-capacity capacitors, in order to serve as battery during rotation-free operation of the shaft (3).

12. Device according to claim 1, further comprising one or more hydraulic pumps (19b) in a barrel arrangement around the shaft (3) and driven by the latter by means of a pinion-step-up gear assembly (18).

13. Device according to claim 11, characterized in that it contains a rearranged assembly of pumps, generators, solenoid valves, jacks and overpressure valves, set up to activate the deflection system (7), said pumps and said generators being coaxial and sharing the same driving pinion.

14. Device according to claim 1, further comprising means for real time measurement of the torsional angle of the shaft (3) between the bearings (4) and (6), as measurement of the torque at the drilling tool/bit (16).

15. Method for making boreholes necessitating precise control of trajectory, comprising the steps of supplying at least one device according to claim 1 and putting the at least one device into operation to make a borehole.

16. Method according to claim 15, wherein the shaft (3) is bent by means of the deflection system (7) by essentially radial displacement of the steerable case (2) in relation to the main body (1) and/or in relation to the traversing transmission shaft (3).

17. Method according to claim 15, wherein the device further comprises one or more generators (19a) in a barrel arrangement around the shaft (3) and driven by the latter by means of a pinion-step-up gear assembly (18), the said generators being preferably coupled to one or more rectifiers that can be coupled in series or in parallel for a wide speed range, and a plurality of high-capacity capacitors, in order to serve as battery during rotation-free operation of the shaft (3), further comprising the step of analyzing the variations of signals from the generator or generators, with a view to the detection of a malfunction, such as excess speed or chatter.

18. Device according to claim 12, characterized in that it contains a rearranged assembly of pumps, generators, solenoid valves, jacks and overpressure valves, set up to activate the deflection system (7), said pumps and said generators being coaxial and sharing the same driving pinion.