US3816894A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Multi-layer well sand screen
Assignee: BP America Production Co
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Filing: 1972-11-06
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Granted: 1974-06-18
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Expires: 1992-11-06
Abstract
Abstract This is a special downhole multi-layer sand screen for oil and other fluids containing sand. The preferred embodiment of the sand filter includes an outer screen, an intermediate screen and an inner screen although another embodiment may have only an outer and an inner screen. The outermost screen is of larger spacing to retain only the coarser sand particles and the openings in the inner two screens are progressively smaller to retain the less coarse sand material. The coarser sand particles bridge about the larger openings in the outer screens and progressively finer sand materials bridge across the intermediate and inner screens.
Inventors
- 👤 G Howard
- 👤 W Bearden
- 👤 E Bearden
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 16:52
CPC Classifications
E; E21; E21B; E21B43/00; E21B43/02; E21B43/08; E21B43/088; B; B01; B01D; B01D39/00; B01D39/10; E21B43/082; Y; Y10; Y10T; Y10T29/00; Y10T29/49; Y10T29/496; Y10T29/49604
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
212 words
A method of constructing a multi-layer screen filter assembly for use in a well drilled to a fluid-producing formation containing unconsolidated sand which comprises: obtaining for said unconsolidated sand a cumulative screen analysis curve which provides an indication of the grain sizes of the sand at various percentile points including the 50 percentile point, the 20 percentile point, the 15 percentile point and the 5 percentile point; forming an inner screen having a spacing c which is greater than the size of the sand at about the 50 percentile point and less than two times the grain dimension of the sand at about the 15 percentile point of the said cumulative sand analysis curve; forming an intermediate screen spaced around said inner screen and having a spacing b which is greater than the sand dimension at about the 20 percentile point of said cumulative screen analysis curve, b being selected to be greater than c; forming an outer screen spaced about said intermediate screen and having a spacing a which is greater than the sand dimension at about the 5 percentile point of said cumulative screen analysis curve, a being selected to be greater than b; and closing the spaces at the upper end and the lower end between the three screens.
Claim 2
Independent Claim
212 words
A method of constructing a multi-layer screen filter assembly for use in a well drilled to a fluid-producing formation containing unconsolidated sand which comprises: obtaining for said unconsolidated sand a cumulative screen analysis curve which provides an indication of the grain sizes of the sand at various percentile points including the 50 percentile point, the 20 percentile point, the 15 percentile point and the 5 percentile point; forming an inner screen having a spacing c which is greater than the size of the sand at about the 50 percentile point and less than two times the grain dimension of the sand at about the 15 percentile point of the said cumulative sand analysis curve; forming an intermediate screen spaced around said inner screen and having a spacing b which is greater than the sand dimension at about the 20 percentile point of said cumulative screen analysis curve, b being selected to be greater than c; forming an outer screen spaced about said intermediate screen and having a spacing a which is greater than the sand dimension at about the 5 percentile point of said cumulative screen analysis curve, a being selected to be greater than b; and closing the spaces at the upper end and the lower end between the three screens.
Claim 3
Dependent Claim
49 words
A method as defined in claim 1 including the step of providing vertical spacers bars between the screens providing radial spacing between the outer and intermediate screens at least equal to a and providing radial spacing between the intermediate and the inner screen equal to or greater than b.
Claim 4
Dependent Claim
27 words
A method as defined in claim 1 in which the step of forming each screen includes the step of winding a wire segmeg into a cylindrical shape.
Claim 5
Dependent Claim
49 words
A method as defined in claim 3 including the step of providing vertical spacer bars between the screens providing radial spacing between the outer and intermediate screens at least equal to a and providing radial spacing between the intermediate and the inner screen equal to or greater than b.
Claim 6
Independent Claim
217 words
A method of constructing a multi-layer sand screen filter assemy for use in a well drilled to a fluid-producing formation containing unconsolidated sand which comprises: collecting a sample of sand from said formation; obtaining for said collected sand a cumulative screen analysis curve proviDing an indication of grain size at various percentile points including the grain sizes of the sand at a first percentile point, at a second percentile point, and a third percentile point; winding a wire segment into an inner cylindrical member having a spacing c between adjacent turns which is greater than the size of the sand at said first percentile point of said cumulative sand analysis curve; winding a wire segment into an intermediate cylindrical member spaced around said inner cylindrical member and having a spacing b which is about equal to the sand dimension at the second percentile point of said cumulative screen analysis cue, b being greater than c; winding a third wire segment into an outer cylindrical member spaced around said intermediate cylindrical member and having a spacing a which is about equal to sand dimension at the said third percentile point of said cumulative screen analysis curve, a being greater than b; closing the spaces at the upper end and the lower end between the three cylindrical wire segments.
Claim 7
Independent Claim
217 words
A method of constructing a multi-layer sand screen filter assemy for use in a well drilled to a fluid-producing formation containing unconsolidated sand which comprises: collecting a sample of sand from said formation; obtaining for said collected sand a cumulative screen analysis curve proviDing an indication of grain size at various percentile points including the grain sizes of the sand at a first percentile point, at a second percentile point, and a third percentile point; winding a wire segment into an inner cylindrical member having a spacing c between adjacent turns which is greater than the size of the sand at said first percentile point of said cumulative sand analysis curve; winding a wire segment into an intermediate cylindrical member spaced around said inner cylindrical member and having a spacing b which is about equal to the sand dimension at the second percentile point of said cumulative screen analysis cue, b being greater than c; winding a third wire segment into an outer cylindrical member spaced around said intermediate cylindrical member and having a spacing a which is about equal to sand dimension at the said third percentile point of said cumulative screen analysis curve, a being greater than b; closing the spaces at the upper end and the lower end between the three cylindrical wire segments.
Claim 8
Dependent Claim
52 words
A method as defined in claim 5 including the step of providing vertical spacer bars between the outer and intermediate cylindrical members for a spacing at least equal to a and further providing radial spacing bars between the intermediate and inner cylindrical members for a spacing equal to or greater that b.
Claim 9
Dependent Claim
22 words
A method as defined in claim 5 in which said first, second and third percentile points are about 50, 20, and 5.
References Cited (Backward Citations)
US713544A
Cited
US1406825A
Cited
US2458118A
Cited
US2729294A
Cited
US2877852A
Cited
US3101526A
Cited
US3389797A
Cited
US3525139A
Cited
US3385373A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-06-17 | 1977-12-17 | 1978-06-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-06-17 | 1981-12-17 | 1982-06-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-06-17 | 1985-12-17 | 1986-06-18 | $7700.00 | Window Closed / Lapsed |