Patent US5085783A successfully refreshed from Google Patents.
Patent US5134285A successfully refreshed from Google Patents.
US5134285A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Formation density logging mwd apparatus
Assignee: Baker Hughes Oilfield Operations LLC
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Filing: 1991-01-15
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Granted: 1992-07-28
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Expires: 2011-01-15
Abstract
Abstract A measurement-while-drilling (MWD) density tool is provided which incorporates a single gamma ray source and a pair of longitudinally displaced and mutually aligned detector assemblies (i.e., dual scintillation counters). A nuclear source is mounted in a pocket in the sub wall and partially surrounded by gamma ray shielding. The subwall section adjacent the source is expanded radially so as to define a lobe which displaces mud thus reducing borehole and mudcake effects. The two detector assemblies are mounted within a cavity or hatch formed in the subwall and enclosed by a detector hatch cover under ambient pressure. The detector assemblies are fixedly spaced from the source and are also partially surrounded by gamma ray shielding to provide good formation response. The hatch cover is secured to the sub by bolts and contains radiation transparent windows therethrough in alignment with the detector assemblies. A threaded-on fluid displacement sleeve is positioned on the sub and over the detector hatch cover. This sleeve has several important functions including the displacement of borehole fluids, reducing mudcaking which might have an adverse effect on the measurement and maintaining a relatively constant formatio to detector distance. The sleeve is full gage (with respect to the borehole diameter) and includes radiation transparent windows that are positioned over the hatch cover windows in a manner which optimizes the response of the tool. The sleeve includes blades which are configured such as to provide adequate flow area in the annulus between the density sub and formation wall.
Inventors
- 👤 Carl A. Perry
- 👤 Guy A. Daigle
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 03:27
CPC Classifications
E; E21; E21B; E21B47/00; E21B47/01; E21B47/017; G; G01; G01V; G01V5/00; G01V5/04; G01V5/08; G01V5/12
Claims Analysis
Total Claims: 65
Claim 1
Independent Claim
200 words
A formation density logging apparatus comprising: a drill collar sub having a sub wall and having opposed ends; a radioactive source in said sub; at least one detector assembly in said sub, said detector assembly being spaced from said radioactive source and said detector assembly being positioned to detect radiation resulting from gamma rays emitted by said source; at least one chamber in said sub wall for housing said detector assembly; at least one chamber cover, said chamber cover including attachment means for forming fluid tight and removable attachment to said at least one chamber, said chamber cover including at least one first radiation transparent window in alignment with said detector assembly for directing gamma rays to said detector assembly; and fluid displacement sleeve means mounted over said drill collar sub and covering at least a portion of said chamber cover, said sleeve means comprising a permanently rigid body which completely surrounds said drill collar sub, said sleeve means including at least one second radiation transparent window, said second window being aligned with said first window and said detector assembly for directing gamma rays to said detector assembly, said sleeve means displacing fluid from the vicinity of said second window.
Claim 2
Dependent Claim
200 words
A formation density logging apparatus comprising: a drill collar sub having a sub wall and having opposed ends; a radioactive source in said sub; at least one detector assembly in said sub, said detector assembly being spaced from said radioactive source and said detector assembly being positioned to detect radiation resulting from gamma rays emitted by said source; at least one chamber in said sub wall for housing said detector assembly; at least one chamber cover, said chamber cover including attachment means for forming fluid tight and removable attachment to said at least one chamber, said chamber cover including at least one first radiation transparent window in alignment with said detector assembly for directing gamma rays to said detector assembly; and fluid displacement sleeve means mounted over said drill collar sub and covering at least a portion of said chamber cover, said sleeve means comprising a permanently rigid body which completely surrounds said drill collar sub, said sleeve means including at least one second radiation transparent window, said second window being aligned with said first window and said detector assembly for directing gamma rays to said detector assembly, said sleeve means displacing fluid from the vicinity of said second window.
Claim 3
Dependent Claim
41 words
The apparatus of claim 1 wherein said sub has an interior flow passage for the flow of drilling fluid therethrough and wherein: a substantial portion of said interior flow passage is axial offset from a central longitudinal axis of said sub.
Claim 4
Dependent Claim
26 words
The apparatus of claim 1 including: source gamma shielding substantially surrounding said radioactive source with the exception of a gamma ray exit surface on said source.
Claim 5
Dependent Claim
21 words
The apparatus of claim 3 including: a source pocket in said sub wall for housing said source shielding and said source.
Claim 6
Dependent Claim
49 words
The apparatus of claim 4 wherein: said source shielding is split defining a first rear shield and a second front shield with said front shield having an opening therethrough for housing a third radiation transparent window, said opening being aligned with said gamma ray exit surface of said source.
Claim 7
Dependent Claim
37 words
The apparatus of claim 5 including: a source pocket cover removably attached to said source pocket for retaining said source gamma shielding therein, said cover including an opening with said third window being exposed by said opening.
Claim 8
Dependent Claim
14 words
The apparatus of claim 5 wherein said third window has a generally conical configuration.
Claim 9
Dependent Claim
16 words
The apparatus of claim 7 including: a groove positioned laterally through said conically configured third window.
Claim 10
Dependent Claim
22 words
The apparatus of claim 8 wherein: said groove is aligned eccentrically with respect to a centerline of said conically configured third window.
Claim 11
Dependent Claim
20 words
The apparatus of claim 1 wherein: said source is adapted to be exposed to drilling fluids through said first opening.
Claim 12
Dependent Claim
26 words
The apparatus of claim 1 wherein said sub has a longitudinal axis and wherein: said source is mounted orthogonal to said longitudinal axis of said sub.
Claim 13
Dependent Claim
21 words
The apparatus of claim 1 wherein: said sub wall surrounding said radioactive source radiates outwardly to define a fluid displacing lobe.
Claim 14
Dependent Claim
23 words
The apparatus of claim 1 wherein: said fluid displacement sleeve means includes a plurality of spaced blades and fluid channels between said blades.
Claim 15
Dependent Claim
43 words
The apparatus of claim 12 wherein: said fluid displacement sleeve means includes a plurality of spaced blades and fluid channels between said blades, a first of said blades housing said second radiation transparent window, and said first blade being aligned with said lobe.
Claim 16
Dependent Claim
18 words
The apparatus of claim 14 wherein: said first blade diverges outwardly at a lower portion nearest said lobe.
Claim 17
Dependent Claim
36 words
The apparatus of claim 1 wherein said fluid displacement sleeve means extends to and covers said radioactive source, and including: a third radiation transparent window in said sleeve means and in alignment with said radioactive source.
Claim 18
Dependent Claim
30 words
The apparatus of claim 1 wherein said fluid displacement sleeve means includes: at least one gage opening therethrough for venting drilling fluid between said sleeve means and said sub wall.
Claim 19
Dependent Claim
35 words
The apparatus of claim 1 wherein: said sleeve means includes first threading and said sub wall includes second threading, said first threading mating with said second threading for retaining said sleeve means to said sub.
Claim 20
Dependent Claim
15 words
The apparatus of claim 18 wherein: said first and second threading comprises stub acme threads.
Claim 21
Dependent Claim
27 words
The apparatus of claim 1 including: key means in said sleeve means and said sub for measuring rotation of said sleeve means with respect to said sub.
Claim 22
Dependent Claim
22 words
The apparatus of claim 1 including: key means in said sleeve means for precluding rotation of said sleeve means beyond preselected limits.
Claim 23
Dependent Claim
33 words
The apparatus of claim 4 including: an opening through said source gamma shielding for housing a third radiation transparent window, said opening being aligned with said gamma ray exit surface of said source.
Claim 24
Dependent Claim
30 words
The apparatus of claim 22 wherein: said first window comprises a low Z, high strength material; and said second and third windows comprise a low Z, high wear resistant material.
Claim 25
Dependent Claim
38 words
The apparatus of claim 1 including: detector gamma shielding cradling and partially surrounding said detector assembly, said detector shielding preventing gamma rays from backscattering and from directly travelling through said sub between said source and said detector assembly.
Claim 26
Dependent Claim
13 words
The apparatus of claim 1 including: two spaced detector assemblies in said chamber.
Claim 27
Dependent Claim
25 words
The apparatus of claim 1 including: a plurality of chambers; and a plurality of chamber covers removably attached to one of each of said chambers.
Claim 28
Dependent Claim
18 words
The apparatus of claim 26 including: three aligned chambers equally spaced about the outer circumference of said sub.
Claim 29
Dependent Claim
56 words
The apparatus of claim 26 including: three aligned chambers equally spaced about the outer circumference of said sub with said at least one detector assembly residing in a first of said three chambers, microprocessor means residing in a second of said three chambers and a power supply means residing in a third of said three chambers.
Claim 30
Dependent Claim
134 words
A formation density logging apparatus comprising: a drill collar sub having a sub wall and having opposed ends; a radioactive source in said sub; at least one detector assembly in said sub, said detector assembly being spaced from said radioactive source and said detector assembly being positioned to detect radiation resulting from gamma rays emitted by said source; and fluid displacement sleeve means mounted over said drill collar sub and covering at least a portion of said drill collar sub, said sleeve means comprising a permanently rigid body which completely surrounds said drill collar sub, said sleeve means including at least one first radiation transparent window, said window being aligned with said detector assembly for directing gamma rays to said detector assembly, said sleeve means displacing fluid from the vicinity of said first window.
Claim 31
Dependent Claim
134 words
A formation density logging apparatus comprising: a drill collar sub having a sub wall and having opposed ends; a radioactive source in said sub; at least one detector assembly in said sub, said detector assembly being spaced from said radioactive source and said detector assembly being positioned to detect radiation resulting from gamma rays emitted by said source; and fluid displacement sleeve means mounted over said drill collar sub and covering at least a portion of said drill collar sub, said sleeve means comprising a permanently rigid body which completely surrounds said drill collar sub, said sleeve means including at least one first radiation transparent window, said window being aligned with said detector assembly for directing gamma rays to said detector assembly, said sleeve means displacing fluid from the vicinity of said first window.
Claim 32
Dependent Claim
21 words
The apparatus of claim 29 wherein: said sub wall surrounding said radioactive source radiates outwardly to define a fluid displacing lobe.
Claim 33
Dependent Claim
23 words
The apparatus of claim 29 wherein: said fluid displacement sleeve means includes a plurality of spaced blades and fluid channels between said blades.
Claim 34
Dependent Claim
43 words
The apparatus of claim 30 wherein: said fluid displacement sleeve means includes a plurality of spaced blades and fluid channels between said blades, a first of said blades housing said second radiation transparent windows, and said first blade being aligned with said lobe.
Claim 35
Dependent Claim
18 words
The apparatus of claim 32 wherein: said first blade diverges outwardly at a lower portion nearest said lobe.
Claim 36
Dependent Claim
35 words
The apparatus of claim 29 wherein: said sleeve means includes first threading and said sub wall includes second threading, said first threading mating with said second threading for retaining said sleeve means to said sub.
Claim 37
Dependent Claim
15 words
The apparatus of claim 34 wherein: said first and second threading comprises stub acme threads.
Claim 38
Dependent Claim
32 words
The apparatus of claim 29 including: at least one second radiation transparent window in said sub adjacent said detector assembly and in alignment with said window in said fluid displacement sleeve means.
Claim 39
Dependent Claim
36 words
The apparatus of claim 29 wherein said fluid displacement sleeve means extends to and covers said radioactive source, and including: a second radiation transparent window in said sleeve means and in alignment with said radioactive source.
Claim 40
Dependent Claim
30 words
The apparatus of claim 29 wherein said fluid displacement sleeve means includes: at least one gage opening therethrough for venting drilling fluid between said sleeve means and said sub wall.
Claim 41
Dependent Claim
27 words
The apparatus of claim 29 including: key means in said sleeve means and said sub for measuring rotation of said sleeve means with respect to said sub.
Claim 42
Dependent Claim
22 words
The apparatus of claim 29 including: key means in said sleeve means for precluding rotation of said sleeve means beyond preselected limits.
Claim 43
Dependent Claim
94 words
A formation density logging apparatus comprising: a drill collar sub having a sub wall and having opposed ends; a radioactive source in said sub; at least one detector assembly in said sub, said detector assembly being spaced from said radioactive source and said detector assembly being positioned to detect radiation resulting from gamma rays emitted by said source; source gamma shielding substantially surrounding said radioactive source with the exception of a gamma ray exit surface on said source; and a source pocket in said sub wall for housing said source shielding and said source.
Claim 44
Dependent Claim
94 words
A formation density logging apparatus comprising: a drill collar sub having a sub wall and having opposed ends; a radioactive source in said sub; at least one detector assembly in said sub, said detector assembly being spaced from said radioactive source and said detector assembly being positioned to detect radiation resulting from gamma rays emitted by said source; source gamma shielding substantially surrounding said radioactive source with the exception of a gamma ray exit surface on said source; and a source pocket in said sub wall for housing said source shielding and said source.
Claim 45
Dependent Claim
48 words
The apparatus of claim 41 wherein: said source shielding is split defining a first rear shield and a second front shield with said front shield having an opening therethrough for housing a radiation transparent window, said opening being aligned with said gamma ray exit surface of said source.
Claim 46
Dependent Claim
36 words
The apparatus of claim 42 including: a source pocket cover removably attached to said source pocket for retaining said source gamma shielding therein, said cover including an opening with said window being exposed by said opening.
Claim 47
Dependent Claim
13 words
The apparatus of claim 42 wherein said window has a generally conical configuration.
Claim 48
Dependent Claim
15 words
The apparatus of claim 44 including: a groove positioned laterally through said conically shaped window.
Claim 49
Dependent Claim
21 words
The apparatus of claim 45 wherein: said groove is aligned eccentrically with respect to a centerline of said conically configured window.
Claim 50
Dependent Claim
26 words
The apparatus of claim 41 wherein said sub has a longitudinal axis and wherein: said source is mounted orthogonal to said longitudinal axis of said sub.
Claim 51
Dependent Claim
21 words
The apparatus of claim 41 wherein: said sub wall surrounding said radioactive source radiates outwardly to define a fluid displacing lobe.
Claim 52
Dependent Claim
11 words
The apparatus of claim 13 wherein said spaced blades are longitudinal.
Claim 53
Dependent Claim
11 words
The apparatus of claim 14 wherein said spaced blades are longitudinal.
Claim 54
Dependent Claim
11 words
The apparatus of claim 31 wherein said spaced blades are longitudinal.
Claim 55
Dependent Claim
11 words
The apparatus of claim 32 wherein said spaced blades are longitudinal.
Claim 56
Dependent Claim
68 words
A fluid displacement sleeve comprising: a tubular housing having an outer surface; a plurality of spaced blades and fluid channels between said blades on said outer surface; at least one radiation transparent window positioned through a first of said blades of said tubular housing; threading on at least one end of said tubular housing for threadably connecting said tubular housing to the exterior of a drill collar sub.
Claim 57
Dependent Claim
68 words
A fluid displacement sleeve comprising: a tubular housing having an outer surface; a plurality of spaced blades and fluid channels between said blades on said outer surface; at least one radiation transparent window positioned through a first of said blades of said tubular housing; threading on at least one end of said tubular housing for threadably connecting said tubular housing to the exterior of a drill collar sub.
Claim 58
Dependent Claim
16 words
The sleeve of claim 53 wherein: said first blade diverges outwardly at a lower portion thereof.
Claim 59
Dependent Claim
26 words
The sleeve of claim 53 including: a second radiation transparent window in said first blade of said sleeve means and in alignment with said first window.
Claim 60
Dependent Claim
31 words
The sleeve of claim 53 wherein said tubular housing includes: at least one gage opening therethrough for venting drilling fluid between said sleeve means and a drill collar sub attached thereto.
Claim 61
Dependent Claim
12 words
The sleeve of claim 52 wherein: said threading comprises stub acme threads.
Claim 62
Dependent Claim
28 words
The sleeve of claim 53 including: key means in said tubular housing for measuring rotation of said tubular housing with respect to a drill collar sub attached thereto.
Claim 63
Dependent Claim
22 words
The sleeve of claim 53 including: key means in said tubular housing for precluding rotation of said tubular housing beyond preselected limits.
Claim 64
Dependent Claim
17 words
The sleeve of claim 53 wherein: said first window comprises a low Z, high wear resistant material.
Claim 65
Dependent Claim
19 words
The sleeve of claim 55 wherein: said first and second window comprises a low Z, high wear resistant material.
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) | 1995-07-28 | 1996-01-27 | 1996-07-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1999-07-28 | 2000-01-27 | 2000-07-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2003-07-28 | 2004-01-27 | 2004-07-28 | $7700.00 | Window Closed / Lapsed |