US4427080A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Apparatus for preventing differential sticking in wells
Assignee: ExxonMobil Upstream Research Co
•
Filing: 1980-12-11
•
Granted: 1984-01-24
•
Expires: 2000-12-11
Abstract
Abstract A porous layer is placed on the outside of various well implements. The layer allows movement of liquid toward sites of localized low pressure and therefore prevents differential pressure stickage of the well implements on the borehole wall.
Inventors
- 👤 Ronald P. Steiger
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 20:03
CPC Classifications
E; E21; E21B; E21B31/00; E21B31/035; E21B17/00; E21B17/10; E21B17/16
Claims Analysis
Total Claims: 36
Claim 1
Independent Claim
28 words
Apparatus suitable for use in a well comprising a substantially imperforate inner sector having an adherent outer porous coating with porosity sufficient to substantially prevent downhole differential sticking.
Claim 2
Dependent Claim
28 words
Apparatus suitable for use in a well comprising a substantially imperforate inner sector having an adherent outer porous coating with porosity sufficient to substantially prevent downhole differential sticking.
Claim 3
Dependent Claim
11 words
The apparatus of claim 1 wherein the outer coating is multi-layered.
Claim 4
Dependent Claim
18 words
The apparatus of claim 2 wherein the outermost layer is less permeable than at least one inner layer.
Claim 5
Dependent Claim
19 words
The apparatus of claim 1 wherein the outer coating is configured in the shape of bands around the apparatus.
Claim 6
Dependent Claim
13 words
The apparatus of claim 1 wherein the outer coating is in mottled configuration.
Claim 7
Dependent Claim
20 words
The apparatus of claim 1 wherein at least a portion of the outer coating is impregnated with a spotting agent.
Claim 8
Dependent Claim
27 words
The apparatus of claim 6 wherein the spotting agent is an oleophilic composition having a viscosity between about that of diesel oil and about that of grease.
Claim 9
Dependent Claim
12 words
The apparatus of claim 7 wherein the spotting agent is diesel oil.
Claim 10
Dependent Claim
21 words
The apparatus of claim 1, 2, 3, 4, 5, or 6 wherein the outer coating is comprised of an iron alloy.
Claim 11
Dependent Claim
15 words
The apparatus of claim 9 wherein the outer coating additionally contains a dispersed abrasive composition.
Claim 12
Dependent Claim
12 words
The apparatus of claim 10 wherein the abrasive composition is tungsten carbide.
Claim 13
Dependent Claim
19 words
A drill collar having an adherent outer porous coating with sufficient porosity to substantially prevent downhole differential pressure sticking.
Claim 14
Dependent Claim
19 words
A drill collar having an adherent outer porous coating with sufficient porosity to substantially prevent downhole differential pressure sticking.
Claim 15
Dependent Claim
11 words
The apparatus of claim 12 wherein the outer coating is multi-layered.
Claim 16
Dependent Claim
18 words
The apparatus of claim 13 wherein the outermost layer is less permeable than at least one inner layer.
Claim 17
Dependent Claim
20 words
The drill collar of claim 12 wherein the outer coating is configured in the shape of bands around the apparatus.
Claim 18
Dependent Claim
15 words
The drill collar of claim 12 wherein the outer coating is in a mottled configuration.
Claim 19
Dependent Claim
21 words
The drill collar of claim 12 wherein at least a portion of the outer coating is impregnated with a spotting agent.
Claim 20
Dependent Claim
28 words
The drill collar of claim 17 wherein the spotting agent is an oleophilic composition having a viscosity between about that of diesel oil and about that of grease.
Claim 21
Dependent Claim
13 words
The drill collar of claim 18 wherein the spotting agent is diesel oil.
Claim 22
Dependent Claim
22 words
The drill collar of claims 12, 13, 14, 15, 16 or 17 wherein the outer coating is comprised of an iron alloy.
Claim 23
Dependent Claim
16 words
The drill collar of claim 20 wherein the outer coating additionally contains a dispersed abrasive composition.
Claim 24
Dependent Claim
13 words
The drill collar of claim 21 wherein the abrasive composition is tungsten carbide.
Claim 25
Dependent Claim
29 words
Apparatus suitable for use in a well comprising a substantially imperforate logging tool having an adherent outer porous coating with sufficient porosity to substantially prevent downhole differential pressure sticking.
Claim 26
Dependent Claim
29 words
Apparatus suitable for use in a well comprising a substantially imperforate logging tool having an adherent outer porous coating with sufficient porosity to substantially prevent downhole differential pressure sticking.
Claim 27
Dependent Claim
11 words
The apparatus of claim 23 wherein the outer coating is multi-layered.
Claim 28
Dependent Claim
18 words
The apparatus of claim 24 wherein the outermost layer is less permeable than at least one inner layer.
Claim 29
Dependent Claim
19 words
The apparatus of claim 23 wherein the outer coating is configured in the shape of bands around the apparatus.
Claim 30
Dependent Claim
14 words
The apparatus of claim 23 wherein the outer coating is in a mottled configuration.
Claim 31
Dependent Claim
20 words
The apparatus of claim 23 wherein at least a portion of the outer coating is impregnated with a spotting agent.
Claim 32
Dependent Claim
27 words
The apparatus of claim 28 wherein the spotting agent is an oleophilic composition having a viscosity between about that of diesel oil and about that of grease.
Claim 33
Dependent Claim
12 words
The apparatus of claim 29 wherein the spotting agent is diesel oil.
Claim 34
Independent Claim
21 words
The apparatus of claims 23, 24, 25, 26, 27 or 28 wherein the outer coating is comprised of an iron alloy.
Claim 35
Dependent Claim
15 words
The apparatus of claim 31 wherein the outer coating additionally contains a dispersed abrasive composition.
Claim 36
Dependent Claim
12 words
The apparatus of claim 32 wherein the abrasive composition is tungsten carbide.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1987-01-23 | 1987-07-25 | 1988-01-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1991-01-23 | 1991-07-25 | 1992-01-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1995-01-23 | 1995-07-25 | 1996-01-24 | $7700.00 | Window Closed / Lapsed |