EP0287155A2
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Assembly for directional drilling of boreholes
Assignee: Shell Internationale Research Maatschappij BV
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Filing: 1988-04-06
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Granted: —
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Expires: 2008-04-06
Abstract
Abstract A directional drilling assembly comprises a downhole drilling motor and stabilizing means which stabilize the assembly in such a manner in the borehole that the bit driven by the output shaft of the motor has a tilted orientation in the hole. The stabilizing means comprise a lowermost stabilizer which is connected to the output shaft of the motor so as to suppress any sticking tendency of said stabilizer to the boreholewall.
Inventors
- 👤 Abe Steiginga
- 👤 Robert Nicholas Worrall
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-04 10:20
CPC Classifications
E; E21; E21B; E21B7/00; E21B7/04; E21B7/06; E21B7/068; E21B17/00; E21B17/10; E21B4/00; E21B4/02
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
92 words
A drilling assembly for directional drilling of boreholes in subsurface formations, the assembly comprising a downhole drilling motor, said motor having an output shaft which is suitable to drive a rotary drill bit and a motor housing which is suitable to be arranged at the lower end of a drill string, and stabilizing means for stabilizing the assembly in a borehole such that in use the output shaft has a tilted orientation in the borehole, characterized in that said stabilizing means include a lowermost stabilizer which is secured to said output shaft.
Claim 2
Dependent Claim
92 words
A drilling assembly for directional drilling of boreholes in subsurface formations, the assembly comprising a downhole drilling motor, said motor having an output shaft which is suitable to drive a rotary drill bit and a motor housing which is suitable to be arranged at the lower end of a drill string, and stabilizing means for stabilizing the assembly in a borehole such that in use the output shaft has a tilted orientation in the borehole, characterized in that said stabilizing means include a lowermost stabilizer which is secured to said output shaft.
Claim 3
Dependent Claim
16 words
The assembly of claim 1, wherein said lowermost stabilizer is mounted concentrically on said output shaft.
Claim 4
Dependent Claim
25 words
The assembly of claim 1, wherein said lowermost stabilizer is mounted on a tubular element which is connected to the lower end of said shaft.
Claim 5
Dependent Claim
23 words
The assembly of claim 1, wherein said lowermost stabilizer is mounted on the shank of a rotary drill bit carried by said shaft.
Claim 6
Dependent Claim
21 words
The assembly of claim 1, wherein said stabilizing means further comprise a second stabilizer which is mounted on the motor housing.
Claim 7
Dependent Claim
16 words
The assembly of claim 5, wherein said second stabilizer is mounted eccentrically on said motor housing.
Claim 8
Dependent Claim
16 words
The assembly of claim 5, wherein said second stabilizer is mounted concentrically on said motor housing.
Claim 9
Dependent Claim
22 words
The assembly of claim 7, wherein said motor housing has a tilted shape in an area between said lowermost and second stabilizer.
Claim 10
Dependent Claim
25 words
The assembly of claim 1, wherein the stabilizing means comprise a second stabilizer which is mounted on a drill string section above the motor housing.
Claim 11
Dependent Claim
47 words
The assembly of claim 9, wherein between said drill string section and motor housing a second downhole motor is arranged, said second motor having a housing which is connected to the housing of said other motor and a shaft which is connected to said drill string section.
Claim 12
Dependent Claim
30 words
The assembly of claim 1, wherein said motor comprises a rotor which is connected to the output shaft and via a second shaft to the drill string above the motor.
Claim 13
Dependent Claim
21 words
The assembly of any one of claims 1-11, wherein each downhole motor is a hydraulically driven motor of the Moineau type.
References Cited (Backward Citations)
No citation records indexed.
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