US3743034A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Steerable drill string
Assignee: Shell USA Inc
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Filing: 1971-05-03
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Granted: 1973-07-03
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Expires: 1991-05-03
Abstract
Abstract Method and apparatus for maintaining the orientation of a laterally unsupported driven shaft constant with respect to a non-rotating coordinate system as the driven shaft is rotated by a non-coaxial rotating driving shaft. In a directional drilling method, the apparatus is disposed in a well drill string along with means for adjusting the orientation of the portion of the drill string below the apparatus to provide a steerable drill string. The apparatus for maintaining the orientation of the shafts comprises an axial-piston machine mounted on one of the shafts and operatively connected to a control flange affixed to the other of the shafts. A universal coupling connects the shaft in driving-driven relationship. The deflection of the shaft at the universal joint is maintained constant with respect to a nonrotating coordinate system by driving the pistons of the axial piston machine in timed relationship with the rotation of the shafts so that each piston completes one reciprocating cycle each time the shafts complete one rotation.
Inventors
- 👤 W Bradley
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 16:23
CPC Classifications
E; E21; E21B; E21B7/00; E21B7/04; E21B7/06
Claims Analysis
Total Claims: 23
Claim 1
Independent Claim
149 words
A method for maintaining the orientation constant with respect to a non-rotating coordinate system of a laterally unsupported driven shaft, connected in end to end relationship with a non-coaxial driving shaft as the driving shaft rotates to drive the driven shaft comprising the steps of interconnecting the shafts through a universal joint means; applying controlled amounts of force to at least one element which is anchored to one of the shafts and moveably coupled to the other of the shafts; and controlling the amount and direction of the applied force in coordination with the rotation of the shafts to dIsplace the element with respect to the shaft to which it is moveably connected in a direction and amount substantially equal to the direction and amount of displacement the element would undergo if the shafts were rotated with the driven shaft supported in the orientation desired to be maintained constant.
Claim 2
Independent Claim
149 words
A method for maintaining the orientation constant with respect to a non-rotating coordinate system of a laterally unsupported driven shaft, connected in end to end relationship with a non-coaxial driving shaft as the driving shaft rotates to drive the driven shaft comprising the steps of interconnecting the shafts through a universal joint means; applying controlled amounts of force to at least one element which is anchored to one of the shafts and moveably coupled to the other of the shafts; and controlling the amount and direction of the applied force in coordination with the rotation of the shafts to dIsplace the element with respect to the shaft to which it is moveably connected in a direction and amount substantially equal to the direction and amount of displacement the element would undergo if the shafts were rotated with the driven shaft supported in the orientation desired to be maintained constant.
Claim 3
Independent Claim
291 words
A method for directionally drilling a well into a subsurface earth formation comprising the steps of affixing a drilling bit to one end of a lower pipe segment; attaching to the opposite end of the lower pipe segment a means for maintaining a selected angle of axial intersection and direction of deflection of the lower pipe segment constant with respect to a reference non-rotating coordinate system as the lower pipe segment is rotated; attaching an upper pipe segment to the means for maintaining a selected angle of axial intersection and direction of deflection constant; extending the drilling bit, lower pipe segment, means for maintaining a selected angle of axial intersection and direction of deflection constant, and upper pipe segment into a well; rotating the upper pipe segment with a rotary drive means at the earth surface to rotate the bit and thereby advance the well into the earth; while rotating the upper pipe segment, applying controlled amounts of force to at least one element of the means for maintaining a selected angle of intersection and direction of deflection constant, the element being anchored to one of the pipe segments and slidably coupled to the other of the pipe segments; and controlling the amount and direction of the force applied to the element in coordination with the rotation of the upper pipe segment to displace the element with respect to the pipe segment to which it is moveably connected in a direction and amount substantially equal to the direction and amount of displacement the element would undergo if the pipe segment were rotated with the lower pipe segment supported at the angle of inclination and direction of deflection at which it is desired to advance the drilling bit into the earth formation.
Claim 4
Independent Claim
291 words
A method for directionally drilling a well into a subsurface earth formation comprising the steps of affixing a drilling bit to one end of a lower pipe segment; attaching to the opposite end of the lower pipe segment a means for maintaining a selected angle of axial intersection and direction of deflection of the lower pipe segment constant with respect to a reference non-rotating coordinate system as the lower pipe segment is rotated; attaching an upper pipe segment to the means for maintaining a selected angle of axial intersection and direction of deflection constant; extending the drilling bit, lower pipe segment, means for maintaining a selected angle of axial intersection and direction of deflection constant, and upper pipe segment into a well; rotating the upper pipe segment with a rotary drive means at the earth surface to rotate the bit and thereby advance the well into the earth; while rotating the upper pipe segment, applying controlled amounts of force to at least one element of the means for maintaining a selected angle of intersection and direction of deflection constant, the element being anchored to one of the pipe segments and slidably coupled to the other of the pipe segments; and controlling the amount and direction of the force applied to the element in coordination with the rotation of the upper pipe segment to displace the element with respect to the pipe segment to which it is moveably connected in a direction and amount substantially equal to the direction and amount of displacement the element would undergo if the pipe segment were rotated with the lower pipe segment supported at the angle of inclination and direction of deflection at which it is desired to advance the drilling bit into the earth formation.
Claim 5
Dependent Claim
56 words
The method of claim 2 including the step of adjusting the for maintaining a selected angle of inclination and direction of deflection by sending a signal via a telemetering drill string from the earth surface to a control means carried by the means for maintaining a selected angle of axial intersection and direction of deflection constant.
Claim 6
Dependent Claim
40 words
The method of claim 2 including the step of measuring the orientation of the lower pipe segment while the lower pipe segment is in the operative position to determine the direction in which the well is advancing into the earth.
Claim 7
Dependent Claim
27 words
The method of claim 4 including the step of signaling the measured orientation of the lower pipe segment to the earth surface via a telemetering drill string.
Claim 8
Dependent Claim
150 words
Apparatus for maintaining the orientation constant with respect to a non-rotating coordinate system of a laterally unsupported driven shaft connected in end to end relationship with a non-coaxial driving shaft as the driving shaft rotates to drive the driven shaft comprising: universal coupling means coupling the driving shaft to the driven shaft; a plurality of control elements each of which is anchored on a first of the shafts and moveably connected to the second of the shafts; and means for applying controlled amounts of force to the control elements in coordination with the rotation of the shafts to displace the control elements with respect to the shaft to which they are moveably connected in a direction and amount substantially equal to the direction and amount of displacement the control elements would undergo if the shafts were rotated with the driven shaft supported in an orientation desired to be maintained constant.
Claim 9
Dependent Claim
150 words
Apparatus for maintaining the orientation constant with respect to a non-rotating coordinate system of a laterally unsupported driven shaft connected in end to end relationship with a non-coaxial driving shaft as the driving shaft rotates to drive the driven shaft comprising: universal coupling means coupling the driving shaft to the driven shaft; a plurality of control elements each of which is anchored on a first of the shafts and moveably connected to the second of the shafts; and means for applying controlled amounts of force to the control elements in coordination with the rotation of the shafts to displace the control elements with respect to the shaft to which they are moveably connected in a direction and amount substantially equal to the direction and amount of displacement the control elements would undergo if the shafts were rotated with the driven shaft supported in an orientation desired to be maintained constant.
Claim 10
Dependent Claim
114 words
The apparatus of claim 6 including: a housing mounted on a first of the shafts; and a control flange affixed to the second shaft; and wherein the plurality of control elements comprise a plurality of pistons sLideably mounted within the housing for reciprocating movement in a direction coaxial with the first shaft; and a plurality of connecting rods, each connecting rod connected to one of the pistons at one end of the rod and pivotably mounted on the control flange at the other end of the rod for maintaining the point of mounting of the rod on the control flange a fixed distance from the piston as the piston moves reciprocally within the housing.
Claim 11
Dependent Claim
99 words
The apparatus of claim 7 wherein the means for applying controlled amounts of force to the control elements in coordination with the rotation of the shafts comprises: variable amplitude drive means for reciprocally driving the pistons within the housing; and timing means associated with the drive means for timing the motion of each piston to complete one full reciprocating cycle each time the driven shaft completes one revolution whereby the connecting rods maintain the orientation of the control flange substantially constant with respect to a non-rotating coordinate system as the driving shaft is rotated to drive the driven shaft.
Claim 12
Dependent Claim
14 words
The apparatus of claim 8 wherein the variable amplitude drive means comprises a pump.
Claim 13
Dependent Claim
14 words
The apparatus of claim 8 wherein the timing means comprises an inertial reference means.
Claim 14
Dependent Claim
200 words
A directionally controllable well drill string for connecting rotary drive means on the earth surface in driving relationship to a drilling bit in a well borehole comprising: an upper pipe segment adapted to be coupled to the rotary drive means for transmitting rotation from the rotary drive means; a lower pipe segment adapted to be coupled to the drilling bit for transmitting rotation to the bit; universal coupling means coupling the upper pipe segment in rotary driving relationship to the lower pipe segment; and means for maintaining a selected angle of axial intersection and direction of deflection of the lower pipe segment with respect to the upper pipe segment constant with respect to a non-rotating coordinate system as the drill string is rotated by the rotary drive means to drive the drilling bit, the means for maintaining a selected angle of axial intersection and direction of deflection constant comprising an axial piston machine carried by one of the pipe segments and a control flange affixed to the other of the pipe segments, the axial piston machine being operatively connected to the control flange to maintain the control flange in a substantially fixed plane with respect to a non-rotating coordinate system.
Claim 15
Dependent Claim
200 words
A directionally controllable well drill string for connecting rotary drive means on the earth surface in driving relationship to a drilling bit in a well borehole comprising: an upper pipe segment adapted to be coupled to the rotary drive means for transmitting rotation from the rotary drive means; a lower pipe segment adapted to be coupled to the drilling bit for transmitting rotation to the bit; universal coupling means coupling the upper pipe segment in rotary driving relationship to the lower pipe segment; and means for maintaining a selected angle of axial intersection and direction of deflection of the lower pipe segment with respect to the upper pipe segment constant with respect to a non-rotating coordinate system as the drill string is rotated by the rotary drive means to drive the drilling bit, the means for maintaining a selected angle of axial intersection and direction of deflection constant comprising an axial piston machine carried by one of the pipe segments and a control flange affixed to the other of the pipe segments, the axial piston machine being operatively connected to the control flange to maintain the control flange in a substantially fixed plane with respect to a non-rotating coordinate system.
Claim 16
Dependent Claim
41 words
The apparatus of claim 11 including: means for adjusting the selected angle of axial intersection of the upper pipe segment with the lower pipe segment from the earth surface while the drill string is operatively positioned in the well bore hole.
Claim 17
Dependent Claim
73 words
The apparatus of claim 12 including: means mounted on the lower pipe segment for measuring the angle of the axis of the lower pipe segment with respect to the vertical; means operatively connected to the angle measuring means for signaling to the surface the angle measured by the angle measuring means; and means at the earth surface operatively connected to the signaling means for displaying the angle measured by the angle measured means.
Claim 18
Dependent Claim
18 words
The apparatus of claim 13 wherein the signaling means comprises circuit means disposed in the upper pipe segment.
Claim 19
Dependent Claim
209 words
The apparatus of claim 11 wherein the axial-piston machine comprises: a housing; a plurality of pistons slideably mounted within the housing for reciprocating movement in a direction co-axial with the pipe segment upon which the housing is carried; variable amplitude drive means for reciprocally driving the pistons within the housing; a plurality of connecting rods, one connecting rod connected to each of the pistons at one end of the rod and pivotably mounted on the control flange at the other end of the rod for maintaining the point of mounting of the rod on the control flange a fixed distance from the piston as the piston moves reciprocally in the housing; and timing means associated with the drive means for timing the motion of each piston to complete one full reciprocating cycle each time the drilling bit completes one revolution whereby the connecting rods maintain the control flange in a substantially fixed plane with respect to a non-rotating coordinate system as the drill string is rotated to drive the drilling bit, the angle of intersection of the fixed plane with the axis of the pipe segment upon which the axial-piston machine is carried being a function of the amplitude of the reciprocal motion of the pistons in the housing.
Claim 20
Dependent Claim
14 words
The apparatus of claim 15 wherein the variable amplitude drive means comprises a pump.
Claim 21
Dependent Claim
14 words
The apparatus of claim 15 wherein the timing means comprises an inertial reference means.
Claim 22
Dependent Claim
46 words
The apparatus of claim 15 including means for controlling the amplitude of the variable amplitude drive means from the earth surface and thereby controlling the angle of intersection of said fixed plane with the axis of the pipe segment upon which the axial-piston machine is carried.
Claim 23
Dependent Claim
119 words
The apparatus of claim 15 wherein the timing means includes means for adjusting the phase of the reciprocating motion of the pistons with respect to the rotation of the drilling bit thereby rotating the plane of the control flange within the non-rotating coordinate system to change the direction of deflection of the lower pipe segment with respect to the upper pipe segment; and wherein the means for adjusting the phase of the reciprocating motion of the pistons is coupled to a phase control means at the earth surface for activating the means for adjusting the phase of the reciprocating motion of the pistons to change the deflection of the lower pipe segment with respect to the upper pipe segment.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-07-02 | 1977-01-01 | 1977-07-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-07-02 | 1981-01-01 | 1981-07-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-07-02 | 1985-01-01 | 1985-07-03 | $7700.00 | Window Closed / Lapsed |