Patent US3908759A successfully refreshed from Google Patents.
US3908759A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Sidetracking tool
Assignee: Standard Oil Co
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Filing: 1974-05-22
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Granted: 1975-09-30
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Expires: 1994-05-22
Abstract
Abstract A new apparatus and method are described for side-tracking a hole drilled in the earth and lined with casing. A modified bridge plug having a latch-up device on top is set using an electric cable in the casing at a point just below where it is desired to drill through the casing wall. A casing whipstock with a latch-up device to match that on the bridge plug is then run to latch up with the latch-up on the bridge plug. The whipstock is sheared and a window is started with a starting mill of the whipstock. A specially modified diamond side-track bit is then used to finish cutting the casing window and milling the window and starting a side-tracked hole in the formation.
Inventors
- 👤 William S Cagle
- 👤 Fred H Dillard
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 14:36
CPC Classifications
E; E21; E21B; E21B7/00; E21B7/04; E21B7/06; E21B7/061; E21B29/00; E21B29/06
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
161 words
A downhole device for setting in a cased wellbore, from which it is desired to drill a side-tracked well, which comprises: an anchor means for anchoring in said cased borehole; an anchor means extension extending upwardly from said anchor means, and including latching means having: a hollow cylindrical member having an internal latching groove near its upper end; internal spline means on the internal surface of the said cylindrical member; a cup-like member set in said cylindrical member; a first shear pin holding said cup-like member to said cylindrical member; a whipstock; a whipstock extension including a lower cylindrical member for fitting into said cup-like member and an intermediate cylindrical portion above said lower portion and having external splines thereon, said external splines matching the internal splines of said cylindrical member of said anchor means extension when inserted therein; latching dogs on said intermediate member of said whipstock extension for latching into said latching grooves of said anchor means'' cylindrical member.
Claim 2
Dependent Claim
161 words
A downhole device for setting in a cased wellbore, from which it is desired to drill a side-tracked well, which comprises: an anchor means for anchoring in said cased borehole; an anchor means extension extending upwardly from said anchor means, and including latching means having: a hollow cylindrical member having an internal latching groove near its upper end; internal spline means on the internal surface of the said cylindrical member; a cup-like member set in said cylindrical member; a first shear pin holding said cup-like member to said cylindrical member; a whipstock; a whipstock extension including a lower cylindrical member for fitting into said cup-like member and an intermediate cylindrical portion above said lower portion and having external splines thereon, said external splines matching the internal splines of said cylindrical member of said anchor means extension when inserted therein; latching dogs on said intermediate member of said whipstock extension for latching into said latching grooves of said anchor means'' cylindrical member.
Claim 3
Dependent Claim
41 words
Apparatus, as defined in claim 1, including a second shear pin in the upper portion of said whipstock and extending horizontally beyond the face of said whipstock, said second shear pin having a higher shear strength than said first shear pin.
Claim 4
Dependent Claim
42 words
Apparatus, as defined in claim 2, including a drill string suspended in said cased borehole, a starting mill with pilot connected to the lower end of said drill string, the lower end of said pilot being connected to said second shear pin.
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) | 1978-09-29 | 1979-03-31 | 1979-09-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-09-29 | 1983-03-31 | 1983-09-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-09-29 | 1987-03-31 | 1987-09-30 | $7700.00 | Window Closed / Lapsed |